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1.
Objective: To investigate the cytokine response pattern (IL-4/IFN-γ) in infants with RSV infections and bronchiolitis during the acute phase. Methods: Four-color flow cytometry was used to measure intracellular IL-4 and IFN-γ expressions in peripheral blood CD3+ and CD8+ lymphocytes from RSV-infected and bronchiolitis infants. Serum IL-4 and IFN-γ levels were also determined. Results: RSV-infected and bronchiolitis infants showed no statistical differences from not-RSV-infected or pneumonia infants and control in the frequency of IL-4 and IFN-γ expressions in CD3+CD8- lymphocytes, showed no obvious Th1/Th2 imbalance, while IFN-γ was expressed much more frequently in CD3+CD8+ lymphocytes. Systematically, RSV-infected and bronchiolitis infants showed much lower levels of serum IL-4 and IL-4/IFN-γ ratios and much higher serum IFN-γ levels than control. However, there were no statistical differences in the above three indices between RSV-infected and not-RSV infected infants or between bronchiolitis and pneumonia infants, except that bronchiolitis infants had a higher level of serum IFN-γ than pneumonia infants statistically. Conclusions: There is no type-2 cytokine response predominance in the acute phase of RSV infection and bronchiolitis. IL-4 production is suppressed and IFN-γ production upregulated, the latter being most prominent in bronchiolitis infants.  相似文献   

2.
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3.
Objective: To evaluate the effects oftramadol on the proinflammatory responses in a rat model of incisional pain by investigating its effects on nociceptive thresholds and serum interleukin-6 (IL-6) and IL-2 levels. Methods: Forty-two male Sprague-Dawley (SD) rats scheduled for plantar incision were randomly divided into 7 groups (n=6 in each group). Rats in Group 1 receiving general anesthesia with no incision were served as control; At 30 min before skin incision, Groups 2～5 were given 5 ml normal saline or 1, 10, and 20 mg/kg tramadol, respectively, intraperitoneally (i.p.); Group 6 received 10 mg/kg tramadol after operation; Group 7 received 10 mg/kg tramadol before incision, followed by 200 μg/kg naloxone after operation. Mechanical allodynia was measured by electronic von Frey filament to evaluate the nociceptive thresholds 1 h before incision, and 1 h and 2 h after operation. Serum IL-6 and IL-2 levels were measured by enzyme-linked immunosorbent assay (ELISA) 2 h after operation. Results: Mechanical thresholds decreased significantly and serum IL-6 level increased significantly after operation in Group 2 compared with control (P＜0.01), and these changes were reversed respectively by tramadol in a dose-dependent manner (P＜0.05 and P＜0.01, respectively). IL-2 level remained unchanged after operation in Group 2, but decreased in Group 3 (P＜0.05), then gradually returned to the normal level in Groups 4 and 5. The intraperitoneally injected tramadol (10 and 20 mg/kg) produced a potent and dose-dependent antinocicptive effect on the lesioned paw. The antinocicptive effects of tramadol were partially an-tagonized by naloxone (200 μg/kg), suggesting an additional non-opioid mechanism. Conclusion: The results suggest that tramadol could be a good choice for the treatment of pain under the conditions that immunosuppression may be particularly contraindicated.  相似文献   

4.
    
Objective: To investigate the immunological function of a yeast expression system for thymosin α1 (Tα1). Methods: A constructed Tα1 yeast expression system was used to investigate the immunological function of orally administered Tα1. Dried yeast containing three different concentration of Tα1 was fed to normal Balb/c mice and other Balb/c mice whose immunities were inhibited in advance by cyclophosphamide. Synthesized Tα1 peptide was used as positive control and dried yeast with empty plasmid was used as negative control. CD4+ and CD8+ levels were detected by flow cytometry assay. TNF-α, IFN-γ, IL-2, IL-6 and IL-10 levels were detected by liquid chip. Results: In normal Balb/c mice or immune inhibition Balb/c mice, CD8+ levels were significantly increased. Especially in immune inhibition Balb/c mice, CD8+ levels in synthesized Tα1 group (18.77%±4.72%), small dose group (13.48%±6.17%) and large dose group (22.74%±1.09%) were significantly higher than that in empty yeast control group (7.49%±2.14%). Conclusion: Orally administered Tα1 has its certain immunomodulatory function. Project (No. 2003C13015) supported by the Key Project from Science and Technology Department of Zhejiang Province, China  相似文献   

5.
Background: Allogeneic blood transfusion-induced immunomodulation (TRIM) and its adverse effect on the prognosis of patients treated surgically for cancer remain complex and controversial. However, the potential risk associated with allogeneic blood transfusion has heightened interest in the use of autologous blood transfusion. In the present study, the serum concentrations of neopterin, interferon-gamma (IFN-γ), T lymphocyte subsets (CD3 , CD4 , CD8 , CD4 /CD8 ) and a possible association between these variables were investigated. The purpose was to further evaluate the effect of autologous versus allogeneic blood transfusion on immunological status in patients undergoing surgery for gastric cancer. Methods: Sixty ASA I～II (American Society of Anesthesiologists) patients undergoing elective radical resection for stomach cancer were randomly allocated to receive either allogeneic blood transfusion (n=30) or autologous blood transfusion (n=30). Serum concentrations of the neopterin, IFN-γ and T lymphocyte subsets in the recipients were measured before induction of anesthesia, after operation, and on the 5th postoperative day. Results: Both two groups, serum neopterin, IFN-γ, percentages of T-cell subsets (CD3 , CD4 ), and CD4 /CD8 ratio had significantly decreased after operation, but decreased more significantly in group H (receiving allogeneic blood transfusion) than those in group A (receiving autologous whole blood transfusion) (P<0.05). On the 5th postoperative day, serum neopterin, IFN-γ, CD3 , CD4 T-cells, and CD4 /CD8 ratio returned to the baseline values in group A. In contrast, the above remain decreasing in group H, where there were no significant relations between serum neopterin and IFN-γ. Conclusion: Perioperative surgical trauma and stress have an immunosuppressive impact on gastric cancer patients. Allogeneic blood transfusion exacerbates the impaired immune response. Autologous blood transfusion might be significantly beneficial for immune-compromised patients in the perioperative period, clearly showing its superiority over allogeneic blood transfusion.  相似文献   

6.

Objectives

This study aimed to compare the learning curves of percutaneous endoscopic lumbar discectomy (PELD) in a transforaminal approach at the L4/5 and L5/S1 levels.

Methods

We retrospectively reviewed the first 60 cases at the L4/5 level (Group I) and the first 60 cases at the L5/S1 level (Group II) of PELD performed by one spine surgeon. The patients were divided into subgroups A, B, and C (Group I: A cases 1–20, B cases 21–40, C cases 41–60; Group II: A cases 1–20, B cases 21–40, C cases 41–60). Operation time was thoroughly analyzed.

Results

Compared with the L4/5 level, the learning curve of transforaminal PELD at the L5/S1 level was flatter. The mean operation times of Groups IA, IB, and IC were (88.75±17.02), (67.75±6.16), and (64.85±7.82) min, respectively. There was a significant difference between Groups A and B (P<0.05), but no significant difference between Groups B and C (P=0.20). The mean operation times of Groups IIA, IIB, and IIC were (117.25±13.62), (109.50±11.20), and (92.15±11.94) min, respectively. There was no significant difference between Groups A and B (P=0.06), but there was a significant difference between Groups B and C (P<0.05). There were 6 cases of postoperative dysesthesia (POD) in Group I and 2 cases in Group IIA (P=0.27). There were 2 cases of residual disc in Group I, and 4 cases in Group II (P=0.67). There were 3 cases of recurrence in Group I, and 2 cases in Group II (P>0.05).

Conclusions

Compared with the L5/S1 level, the learning curve of PELD in a transforaminal approach at the L4/5 level was steeper, suggesting that the L4/5 level might be easier to master after short-term professional training.
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7.
To evaluate the effects of sperm with different parameters and sources on the outcomes of intracytoplasmic sperm injection (ICSI), 1972 ICSI cycles were analyzed retrospectively. Groups 1 to 5 were composed of cycles using ejaculated sperm and were grouped according to sperm quantity, quality, and morphology into normal (288 cycles), or mild (329 cycles), moderate (522 cycles), severe (332 cycles), and extremely severe (171 cycles) oligozoospermia and/or asthenozoospermia and/or teratozoospermia (OAT) groups. Group 6 was composed of 250 cycles using testicular or epididymal sperm, and Group 7 consisted of 80 cycles using frozen-thawed sperm. We found that fertilization rates were gradually reduced from Groups 1 to 6, and reached statistical difference in Groups 5 and 6 (P<0.05). The high-quality embryo rate was higher in Group 1 than in Groups 2, 3, 5, 6, and 7 (P<0.05). No statistical differences were observed in the rates of embryo cleavage, clinical pregnancy, miscarriage, live-birth, premature birth, low birth weight, weeks of premature birth, average birth weight, or sex ratio for all seven groups (P>0.05). A total of nine cases of malformation were observed, with a malformation rate of 1.25% (9/719). In conclusion, different sperm sources and parameters can affect ICSI outcomes before embryo implantation. A full assessment of offspring malformation will require further study using a larger sample size.  相似文献   

8.
Use and effects of liver specific antigen in orthotopic liver transplantations were researched in this study. Group I: syngeneic control (Wistar-to-Wistar); Group II: acute rejection (SD-to-Wistar); Group III: Thymic inoculation of SD rat LSA day 7 before transplantation. The observation of common situation and survival time, rejection grades, NF-κB activity of splenocytes and IL-2mRNA expression of grafted liver were used to analyze acute rejection severity and immune state of animals in different groups. The common situation of group I was very well after transplantation and no signs of rejection were found. Recipients of group II lost body weight progressively All dead within day 9 to day 13 posttransplantation; median survival time was 10.7 ±0.51 days. It was an optimal acute rejection control. As for group III, 5 out of 6 recipients survived for a long time and common situation was remarkably better than that of group II. Its rejection grades were significantly lower than that of group II(P<0.05). NF-κB activity was only detected in group I at day 5 and day 7 after transplantation, whereas high activity of NF-κB was detected at all time points in groupII and the low NF-κB activity detected in group III was significantly lower than that of group II (P<0.05). No IL-2mRNA expression was detected at any time point in group I, whereas high level expression was detected at all time points in group II and the low level expression only detected at day 3 in group III was significantly lower than that of group II (P<0.05). Conclusion: LSA is an important transplantation antigen which is involved directly in the immunorejection of liver transplantation. We report here for the first time that intrathymic inoculation of LSA can alleviate the rejection of liver allotransplantation; and that grafts can survive for a long time thereby, thus leading to a novel way to achieve liver transplantation immunotolerance. Project (NO. 011106206) supported by the Science and Technology Bureau of Zhejiang Province Foundation  相似文献   

9.
Objective:To evaluate the pharmacological effects of traditional Chinese medicine,bear bile capsule and Huangqi granule,on recurrent parotitis in children.Methods:In this prospective,controlled,and randomized study,a total of 151 young children were divided into three groups:Group A included massaging the children’s parotid region and melting vitamin C in their mouth daily;Group B included swallowing bear bile capsule and Huangqi granule daily;and Group C included massages and vitamin C as prescribed in Group A,and traditional Chinese medicine as prescribed in Group B.Children were treated individually for one month and then a follow-up study was conducted for 1 to 3.5 years.Analysis of variance(ANOVA) and Ridit analysis were employed for statistical analysis.Results:The recurrence rate decreased in every group,but was significantly more in Groups B and C when compared to Group A.The recurrences significantly decreased(P<0.01) in Group B and their recovery rate was as high as 63%,significantly better than those of the other groups(P<0.01).Conclusions:Huangqi and bear bile could be a novel clinical approach for treating recurrent parotitis in children.  相似文献   

10.
Objective: To study the relationships among magnetic resonance imaging (MRI), histological findings, and insulin-like growth factor-I (IGF-I) in steroid-induced osteonecrosis of the femoral head in rabbits. Methods: Thirty rabbits were randomly divided into experimental Group A (n=15) and control Group B (n=15). The 7.5 mg/kg (2 ml) ofdexamethasone (DEX)and physiological saline (2 ml) were injected into the fight gluteus medius muscle twice at one-week intervals in animals of Groups A and B, respectively. At 4, 8 and 16 weeks after obtaining an MRI, the rabbits were sacrificed and the femoral head from one side was removed for histological study of lacunae empty of osteocytes, subchondral vessels, and size of fat cells under microscopy, and the femoral head from the other side was removed for enzyme-linked immunoadsorbent assay (ELISA) for IGF-I.Results: At 4, 8 and 16 weeks after treatment, no necrotic lesions were detected in Group B, while they were detected in Group A.Light microscopy revealed that the fat cells of the marrow cavity were enlarged, subchondral vessels were evidently decreased,and empty bone lacunae were clearly increased. The IGF-I levels in Group A were significantly higher than those in Group B. At 8 weeks after the DEX injection, the MRI of all 20 femora showed an inhomogeneous, low signal intensity area in the femoral head,and at 16 weeks, the findings of all 10 femora showed a specific "line-like sign". The MRI findings of all femora in Group B were normal. Conclusion: MRI is a highly sensitive means of diagnosing early experimental osteonecrosis of the femoral head. However, the abnormal marrow tissues appeared later than 4 weeks when the expression of IGF-I increased. This reparative factor has an early and important role in response to steroid-induced osteonecrosis of the femoral head, and provides a theoretical foundation for understanding the pathology and designing new therapies.  相似文献   

11.
To investigate the inhibiting effect of β-Aescin on nuclear factor-κB(NF-κB)activation and the expression of tumornecrosis factor-α(TNF-α)protein after traumatic brain injury(TBI)in the rat brain,62 SD rats were subjected to lateral corticalimpact injury caused by a free-falling object and divided randomly into four groups:(1)sham operated(Group A);(2) injured(Group B);(3)β-Aescin treatment(Group C);(4) pyrrolidine dithocarbamate(PDTC) treatment(Group D).β-Aescin was ad-ministered in Group C and PDTC treated in Group D immediately after injury.A series of brain samples were obtained directly 6h,24 h and 3 d respectively after trauma in four groups.NF-κB activation was examined by Electrophoretic Mobility Shift Assay(EMSA);the levels of TNF-α protein were measured by radio-immunoassay(RIA);the water content of rat brain was measuredand pathomorphological observation was carried out.NF-κB activation,the levels of TNF-α protein and the water content of ratbrain were significantly increased(P＜0.0  相似文献   

12.
Objective: To investigate the effect of recurrent laryngeal nerve (RLN) identification on the complications after total thyroidectomy and lobectomy. Methods: Total 134 consecutive patients undergoing total thyroidectomy or thyroid lobectomy from January 2003 to November 2004 were investigated retrospectively. Patients were divided into two groups: RLN identified (Group A) or not (Group B). The two groups were compared for RLN injury and hypocalcaemia. Results: The numbers of patients and nerves at risk were 71 and 129 in Group A, and 63 and 121 in Group B, respectively. RLN injury in Group A (0) was significantly lower than that in Group B (5[7.9%]) patients, 7 [5.8%] nerves) for the numbers of patients (P=-0.016) and nerves at risk (P=0.006). Temporary hypocalcaemia was significantly higher in Group A than in Group B (14 [24.1%] vs 6 [10.3%], P=0.049).Permanent complications in Group B were significantly higher than those in Group A (13 [20.6%] vs 4 [5.6%], P=0.009). Conclusion: RLN injury was prevented and permanent complications were decreased by identifying the whole course and branches of the recurrent laryngeal nerve during total thyroidectomy.  相似文献   

13.
Objective: To investigate the influence of lead exposure on the immune function of lymphocytes and erythrocytes in preschool children. Materials and methods: A group of 217 children three to six years of age from a rural area were given a thorough physical examination and the concentration of lead in blood samples taken from each subject was determined. The indices of lymphocyte immunity (CD 3CD 4, CD 3CD 8, CD 4CD 8, CD-3CD 19) and erythrocyte immunity (RBC-C3b, RBC-IC, RFER, RFIR, CD35 and its average fluorescence intensity) of 40 children with blood lead levels above 0.483 μmol/L were measured and compared with a control group. Results: The blood lead levels of the 217 children ranged from 0.11 μmol/L to 2.11 μmol/L. The CD 3CD 4and CD 4CD 8 cells were lower (P＜0.01) and the CD 3CD 8 cells were higher in the lead-poisoned subjects than those in the control group (P＜0.05). CD 3 and CD-3CD 19 did not show significant differences. Although the RBC-C3b rosette forming rate was lower and the RBC-IC rosette forming rate was higher in the lead-poisoned group, this difference could not be shown to be statistically significant (P＞0.05). RFIR was found to be lower in the lead-poisoned group (P＜0.01). Compared with the control group, the positive rate of CD35 was not found to be significantly different in a group of 25 lead-poisoned children (P＞0.05), while the average fluorescence intensity was lower in the lead-poisoned group (P＜0.05). Conclusion: Lead exposure can result in impaired immune function of T lymphocytes and erythrocytes in preschool children.  相似文献   

14.

Objective

The aim of our study is to observe the impact of cholangiocarcinoma-derived exosomes on the antitumor activities of cytokine-induced killer (CIK) cells and then demonstrate the appropriate mechanism.

Methods

Tumor-derived exosomes (TEXs), which are derived from RBE cells (human cholangiocarcinoma line), were collected by ultracentrifugation. CIK cells induced from peripheral blood were stimulated by TEXs. Fluorescence-activated cell sorting (FACS) was performed to determine the phenotypes of TEX-CIK and N-CIK (normal CIK) cells. The concentrations of tumor necrosis factor-α (TNF-α) and perforin in the culture medium supernatant were examined by using an enzyme-linked immunosorbent assay (ELISA) kit. A CCK-8 kit was used to evaluate the cytotoxic activity of the CIK cells to the RBE cell line.

Results

The concentrations of TNF-α and perforin of the group TEX-CIK were 138.61 pg/ml and 2.41 ng/ml, respectively, lower than those of the group N-CIK 194.08 pg/ml (P<0.01) and 3.39 ng/ml (P<0.05). The killing rate of the group TEX-CIK was 33.35%, lower than that of the group N-CIK (47.35% (P<0.01)). The population of CD3+, CD8+, NK (CD56+), and CD3+CD56+ cells decreased in the TEX-CIK group ((63.2±6.8)%, (2.5±1.0)%, (0.53±0.49)%, (0.45±0.42)%) compared with the N-CIK group ((90.3±7.3)%, (65.7±3.3)%, (4.2±1.2)%, (15.2±2.7)%), P<0.01.

Conclusions

Our results suggest that RBE cells-derived exosomes inhibit the antitumor activity of CIK cells by down-regulating the population of CD3+, CD8+, NK (CD56+), and CD3+CD56+ cells and the secretion of TNF-α and perforin. TEX may play an important role in cholangiocarcinoma immune escape.
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15.
Objective: To demonstrate the validity and reliability of volumetric quantitative computed tomography (vQCT) with multi-slice computed tomography (MSCT) and dual energy X-ray absorptiometry (DXA) for hip bone mineral density (BMD) measurements, and to compare the differences between the two techniques in discriminating postmenopausal women with osteoporosis-related vertebral fractures from those without. Methods: Ninety subjects were enrolled and divided into three groups based on the BMD values of the lumbar spine and/or the femoral neck by DXA. Groups 1 and 2 consisted of postmenopausal women with BMD changes ＜-2SD, with and without radiographically confirmed vertebral fracture (n=11 and 33, respectively).Group 3 comprised normal controls with BMD changes ≥-1SD (n=46). Post-MSCT (GE, LightSpeed16) scan reconstructed images of the abdominal-pelvic region, 1.25 mm thick per slice, were processed by OsteoCAD software to calculate the following parameters: volumetric BMD values of trabecular bone (TRAB), cortical bone (CORT), and integral bone (INTGL) of the left femoral neck, femoral neck axis length (NAL), and minimum cross-section area (mCSA). DXA BMD measurements of the lumbar spine (AP-SPINE) and the left femoral neck (NECK) also were performed for each subject. Results: The values of all seven parameters were significantly lower in subjects of Groups 1 and 2 than in normal postmenopausal women (P＜0.05, respectively).Comparing Groups 1 and 2, 3D-TRAB and 3D-INTGL were significantly lower in postmenopausal women with vertebral fracture(s) [(109.8±9.61) and (243.3±33.0) mg/cm3, respectively] than in those without [(148.9±7.47) and (285.4±17.8) mg/cm3,respectively] (P＜0.05, respectively), but no significant differences were evident in AP-SPINE or NECK BMD. Conclusion: the femoral neck-derived volumetric BMD parameters using vQCT appeared better than the DXA-derived ones in discriminating osteoporotic postmenopausal women with vertebral fractures from those without, vQCT might be useful to evaluate the effect of osteoporotic vertebral fracture status on changes in bone mass in the femoral neck.  相似文献   

16.
Objective: To study the effect and implication of nonmyeloablative donor specific bone marrow (DSBM) infusion on the immunoreaction of liver allotransplantation. Methods: Orthotopic liver transplantation model was used in this study. Groups were set as follows: Group Ⅰ, syngeneic control (Wistar-to-Wistar); Group Ⅱ, acute rejection (SD-to-Wistar); Group Ⅲ, acute rejection treated with cyclosporine A (CsA) by intramuscular injection (SD-to-Wistar CsA); Group Ⅳ, bone marrow infusion at 7 d pretransplantation followed by short-term CsA treatment (SD-to-Wistar DSBM); Another group of short-term CsA treatment preoperatively without bone marrow infusion was also set as control. General characteristics and survival time were observed.Histological grades of rejection were determined by pathological examination. IL-2 and IFN-γ level in peripheral blood and donor liver were detected respectively by Enzyme-Linked Immuno-Sorbent Assay (ELISA) and Western blot. Chimerism of donor cells was measured by PCR for a male-specific marker (Y-chromosome-specific sequence, Sry). Results: No signs of rejection were found in Group Ⅰ. Acute rejection occurred in both Group Ⅱ and the short-term CsA treated group. All the recipients died at (9～15)d posttransplantation with a median survival time of (10.7±0.5) d and (11.2±2.4) d, respectively. Only mild rejection could be seen in Group Ⅲ. In Group Ⅳ, 4 out of 6 recipients had long-term survival (＞100 d), the histological grade of rejection was significantly lower than that of Group Ⅱ, so did the expression level of IL-2 and IFN-γ in both peripheral blood and grafted liver.Y-chromosome-specific sequence (Sry) of male SD rats could be detected in the bone marrow, spleen and thymus of female recipients at 15 d after bone marrow infusion. Conclusion: Mild preconditioning nonmyeloablative donor specific bone marrow infusion can enhance chimerism formation in recipients, alleviate the rejection of liver allotransplantation and prolong survival of liver allotransplantation.  相似文献   

17.
To examine the effects of co-culture with bone marrow mesenchymal stem cells on expansion of hematopoietic stem/progenitor cells and the capacities of rapid neutrophil engraftment and hematopoietic reconstitution of the expanded cells, we expanded mononuclear cells (MNCs) and CD34+/c-kit+ cells from mouse bone marrow and transplanted the expanded cells into the irradiated mice. MNCs were isolated from mouse bone marrow and CD34+/c-kit+ cells were selected from MNCs by using MoFlo Cell Sorter. MNCs and CD34+/c-kit+ cells were co-cultured with mouse bone marrow-derived mesenchymal stem cells (MSCs) under a two-step expansion. The expanded cells were then transplanted into sublethally irradiated BDF1 mice. Results showed that the co-culture with MSCs resulted in expansions of median total nucleated cells, CD34+ cells, GM-CFC and HPP-CFC respectively by 10.8-, 4.8-, 65.9- and 38.8-fold for the mononuclear cell culture, and respectively by 76.1-, 2.9-, 71.7- and 51.8-fold for the CD34+/c-kit+ cell culture. The expanded cells could rapidly engraft in the sublethally irradiated mice and reconstitute their hematopoiesis. Co-cultures with MSCs in conjunction with two-step expansion increased expansions of total nucleated cells, GM-CFC and HPP-CFC, which led us to conclude MSCs may create favorable environment for expansions of hematopoietic stem/progenitor cells. The availability of increased numbers of expanded cells by the co-culture with MSCs may result in more rapid engraftment of neutrophils following infusion to transplant recipients. Project supported by NIH-Blood, Heart & Lung (National Institute of Health, USA, IR 01 4L70593-01) and Zhejiang Provincial Science Foundation (No. 011103397), China  相似文献   

18.
During simultaneous discrimination training, there is evidence that some of the value of the S+ transfers to the S?. When the value of the S+ is altered outside the context of the simultaneous discrimination, two very different predictions are made concerning its effect on its S?, depending on whether one views the S+ as an occasion setter or as a stimulus capable of transferring value. In four experiments, pigeons were trained with two similar simultaneous discriminations, A+B? and C+D?, and two single-stimulus trial types, A and C, (in which A always had greater nominal value than C). According to value transfer theory, on test trials, B should always be preferred over D, because B and D should be affected by the net values of A and C, respectively. According to an occasion setting account, however, D should be preferred over B because the presence of D signals a higher probability of reinforcement for responding to C than when C is alone, and/or the presence of B signals a lower probability of reinforcement for responding to A than when A is alone. In all four experiments, the pigeons preferred B over D, a result consistent with value transfer theory. Thus, an S? can acquire value from an S+ even when that value is conditioned in a “context” different from that of the simultaneous discrimination.  相似文献   

19.

Objective

The aim of this study was to evaluate the concentrations of C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and the degree of homeostasis model assessment-insulin resistance (HOMA-IR) in patients with morbid obesity exposed to a three-week low-calorie diet and balneotherapy.

Methods

The study included 33 patients (25 females and 8 males; mean age 46 years) with body mass index (BMI) values of >40 kg/m2. Evaluations of CRP, IL-6, TNF-α, lipid profile, HOMA-IR, and fasting glucose were carried out before (baseline data) and three weeks after the treatment. The control group consisted of 20 healthy volunteers (15 females and 5 males) with a mean age of 39 years and BMI values of ≤24.9 kg/m2.

Results

In the blood of patients with morbid obesity we found significantly elevated levels of CRP, TNF-α, triglycerides, HOMA-IR and fasting glucose, but a decreased level of high density lipoprotein (HDL)-cholesterol, compared with the healthy individuals. The treatment resulted in about a 9.4% reduction in body weight from 122.5 to 111.0 kg and a significant decrease in the concentration of CRP, but no change in TNF-α or IL-6. HOMA-IR was significantly reduced.

Conclusion

The decrease in CRP level without changes in TNF-α or IL-6 concentrations after the low-calorie diet and balneological treatment, suggests that an essential amount of adipose tissue must be removed before proper adipocyte function is restored. The decrease in HOMA-IR indicates an improvement in insulin sensitivity, which is beneficial in obese patients.
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20.
Three groups of 6‐ to 7‐year old children were used to compare the effects of stories read by a teacher with stories viewed on educational television. Weekly, for ten weeks, a story was read to Group A while the same story was seen on television by Groups B and C, Group B being prepared for the story by the teacher and given appropriate follow‐on. Questioning for understanding and recall showed that, at the end of the ten weeks, the largest gains were made by the Group B children, who showed improvement in their classification ability and in application of their understanding to domains beyond the confines of the immediate story structure. Television was preferred by the children for its pictures, movement and action, and generated more detailed understanding and recall, but only when the stories were interpreted and rationalised by the teacher. Video recorder replay is helpful, and teachers need to be taught how best to manage story‐telling with young children  相似文献   

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