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1.
Objective:To investigate the relationship between growth patterns and mandibular posterior tooth-alveolar bone complex morphology in a Chinese population with normal occlusion.Methods:Forty-five patients with normal occlusion(23 males,22 females) were included in this study.Among these patients,20 displayed the vertical growth pattern,and 20 had the horizontal growth pattern,while the remaining patients displayed the average growth pattern.All of the patients underwent dental cone beam computed tomography(CBCT),which included the region of the mandibular posterior teeth and the alveolar.A linear regression analysis and a correlation analysis between the facial height index(FHI) and the alveolar bone morphology were performed.Results:The inclination of the molars,the thickness of the cortical bone,and the height of the mandibular bone differed significantly between patients with the horizontal growth pattern and those with the vertical growth pattern(P<0.05).Significant positive correlations were found between:the FHI and the inclination of the molars;the FHI and the thickness of the cortical bone;and the FHI and the height of the mandibular bone.Conclusions:The mandibular posterior tooth-alveolar bone complex morphology may be affected by growth patterns.  相似文献   

2.
Objective:To investigate the periodontal status and associated risk factors among women of childbearing age to increase the awareness of oral health.Methods:The study was conducted on childbearing age women in Cixi,a city in Zhejiang Province in the southeast of China.A total of 754 women participated in periodontal examination while receiving prenatal care.Data of the women were collected from the Cixi Family Planning Commission and during an interview.Clinical periodontal indices,such as bleeding on probing(BOP),probing depth(PD),and clinical attachment level(CAL) were measured during the examination.Statistical analysis on subject-based data was performed.Results:The prevalence of periodontal disease among childbearing age women in Cixi was high(84.7%).A significant association was found between the disease and educational level,pregnancy,taking oral contraceptives,stress,alcohol consumption,overweight,dental visit,and teeth brushing(P<0.05).Women who suffered periodontal disease showed deep PD,obvious BOP,and clinical attachment loss.Among this population,pregnancy was closely associated with higher BOP percentage;teeth brushing no more than once per day or brushing for less than 1 min(P<0.001) after adjusting for age and stress.Conclusions:The periodontal status of childbearing age women in Cixi needs to be improved urgently.Attention towards the periodontal health should be warranted,especially for those in special statuses and with poor awareness.  相似文献   

3.

Objective

This study investigated the effect of proximal contact strength on the three-dimensional displacements of cantilever fixed partial denture (CFPD) under vertically concentrated loading with digital laser speckle (DLS) technique.

Methods

Fresh mandible of beagle dog was used to establish the implant-supported CFPD for specimen. DLS technique was employed for measuring the three-dimensional displacement of the prosthesis under vertically concentrated loading ranging from 200 to 3 000 g. The effect of the contact tightness on the displacement of CFPD was investigated by means of changing the contact tightness.

Results

When an axial concentrated loading was exerted on the pontic of the implant-supported CFPD, the displacement of the CFPD was the greatest. The displacement of the prosthesis decreased with the increase of contact strength. When the contact strength was 0, 0.95, and 3.25 N, the displacement of the buccolingual direction was smaller than that of the mesiodistal direction but greater than that of the occlusogingival direction. When the force on the contact area was 6.50 N, the mesiodistal displacement of the prosthesis was the biggest while the buccolingual displacement was the smallest.

Conclusions

The implant-supported CFPD is an effective therapy for fully or partially edentulous patients. The restoration of the contact area and the selection of the appropriate contact strength can reduce the displacement of the CFPD, and get a better stress distribution. The most appropriate force value is 3.25 N in this study.  相似文献   

4.
研究目的:通过对一个中国Nance-Horan综合征家系的临床表型及基因突变分析,揭示本家系的致病遗传机制。研究方法:对该Nance—Horan综合征家系的一个男性患者进行全外显子组测序,结合此家系临床表型及遗传方式分析,选定x染色体上NHS基凶上的一个无义突变c.322G〉T(E108x)为可疑致病突变。通过聚合酶链式反应(PCR)和Sanger测序,对该家系内其他成员进行NHS基因突变分析,同时对50名健康对照者的NHS基因的突变检测结果进行对比。另外,将该突变的位点第108位氨基酸残基进行多物种NHS蛋白内序列比对。最后,对该家系成员眼部及全身的临床特点进行全面检查和分析。重要结论:全外显子组测序结合Sanger测序发现NHS基因第一个外显子上的c.322G〉T(E108X)突变为引起该家系临床病变的突变位点;多物种NHS蛋白内序列比对发现该突变位点第108位氨基酸残基位于高度保守区;临床表型分析发现该家系内存在表型异质性。此家系为国内首次报道的无义突变引起的Nance-Horan综合征家系。  相似文献   

5.
Objective:To observe the periodontal healing of autogenously transplanted teeth loaded orthodontically after autotransplantation in Beagle dogs.Methods:Forty-eight teeth were autogenously transplanted,24 of which were loaded postoperatively with orthodontic force at different time points and for different durations.Periodontal healing was evaluated by probing pocket depth(PPD),the expression of relevant proteins,and histomorphometric analyses.Results:The dental pockets of loaded and non-loaded teeth were both much deeper after the first postoperative week than before transplantation(P<0.05).Later,the PPD,which was measured after postoperative weeks 1,3,5,9 and 13,gradually became shallow.The expressions of alkaline phosphatase(ALP)and basic fibroblast growth factor(bFGF)were higher in loaded teeth than in non-loaded teeth(P<0.05),and in groups subjected to two weeks duration of loading than in other groups at the same load time point(P<0.05).For the same load duration,the expressions of ALP and bFGF in teeth loaded after postoperative week 4 were higher than those of other treatments(P<0.05).According to histomorphometric analyses,an orthodontic force on transplanted teeth applied after postoperative weeks 4 or 8 for two weeks duration should be favorable for periodontal healing.Conclusions:It is advisable to apply an appropriate magnitude of force on autotransplanted teeth,such as orthodontic force,at appropriate time points and for a suitable duration,to achieve the optimal clinical prognosis following autogenous tooth transplantation.These results may serve as a basis for subsequent studies in humans so as to make clinical improvements.  相似文献   

6.

Objective

Mesenchymal stem cell (MSC) transplantation is a promising therapy for ischemic heart diseases. However, poor cell survival after transplantation greatly limits the therapeutic efficacy of MSCs. The purpose of this study was to investigate the protective effect of angiopoietin-1 (Ang1) preconditioning on MSC survival and subsequent heart function improvement after transplantation.

Methods

MSCs were cultured with or without 50 ng/ml Ang1 in complete medium for 24 h prior to experiments on cell survival and transplantation. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Hoechst staining were applied to evaluate MSC survival after serum deprivation in vitro, while cell survival in vivo was detected by terminal deoxynucleotidyl transferase biotin-dUPT nick end labeling (TUNEL) assay 24 and 72 h after transplantation. Heart function and infarct size were measured four weeks later by small animal echocardiography and Masson??s trichrome staining, respectively.

Results

Ang1 preconditioning induced Akt phosphorylation and increased expression of Bcl-2 and the ratio of Bcl-2/Bax. In comparison with non-preconditioned MSCs, Ang1-preconditioned cell survival was significantly increased while the apoptotic rate decreased in vitro. However, the PI3K/Akt pathway inhibitor, LY294002, abrogated the protective effect of Ang1 preconditioning. After transplantation, the Ang1-preconditioned-MSC group showed a lower death rate, smaller infarct size, and better heart functional recovery compared to the non-preconditioned-MSC group.

Conclusions

Ang1 preconditioning enhances MSC survival, contributing to further improvement of heart function.  相似文献   

7.

Objective

To report surgical management and favorable outcome in a case with delayed repair of traumatic laser in situ keratomileusis (LASIK) flap dislocation with shrinkage and folds.

Methods

A 30-year-old man with a five-year history of bilateral LASIK experienced blunt trauma to his right eye followed by decreased vision for 5 weeks. The surgical management included initially softening the flap by irrigation with balanced salt solution (BSS). The shrinkage folds were carefully and gently stretched by scraping with a 26-gauge cannula accompanied by BSS irrigation. All of the epithelial ingrowth on the flap inner surface and on the bed was thoroughly debrided by scraping and irrigation. After the flap was repositioned to match its original margin, a soft bandage contact lens was placed.

Results

At his initial visit, slit-lamp microscopy and optical coherence tomography (OCT) showed shrinkage of the LASIK flap with an elevated margin approximately 3 mm above the original position. The flap covered half of the pupil and had multiple horizontal folds. Two months after surgery, the flap remained well positioned with only faint streaks in the anterior stroma. The uncorrected visual acuity of the right eye was 20/20 with a manifest refraction of Plano.

Conclusions

For delayed repair of traumatically dislocated LASIK flaps, sufficient softening by BSS, stretching the shrinkage folds, and thorough debridement of ingrowth epithelium enable resetting the flap and provide satisfactory results.
  相似文献   

8.
Objective:The purpose of this study was to investigate the effects of a zinc-substituted nano-hydroxyapatite(Zn-HA) coating,applied by an electrochemical process,on implant osseointegraton in a rabbit model.Methods:A Zn-HA coating or an HA coating was deposited using an electrochemical process.Surface morphology was examined using field-emission scanning electron microscopy.The crystal structure and chemical composition of the coatings were examined using an X-ray diffractometer(XRD) and Fourier transform infrared spectroscopy(FTIR).A total of 78 implants were inserted into femurs and tibias of rabbits.After two,four,and eight weeks,femurs and tibias were retrieved and prepared for histomorphometric evaluation and removal torque(RTQ) tests.Results:Rod-like HA crystals appeared on both implant surfaces.The dimensions of the Zn-HA crystals seemed to be smaller than those of HA.XRD patterns showed that the peaks of both coatings matched well with standard HA patterns.FTIR spectra showed that both coatings consisted of HA crystals.The Zn-HA coating significantly improved the bone area within all threads after four and eight weeks(P<0.05),the bone to implant contact(BIC) at four weeks(P<0.05),and RTQ values after four and eight weeks(P<0.05).Conclusions:The study showed that an electrochemically deposited Zn-HA coating has potential for improving bone integration with an implant surface.  相似文献   

9.
Local data analysis for eliminating end restraint of triaxial specimen   总被引:1,自引:0,他引:1  
A data processing method was proposed for eliminating the end restraint in triaxial tests of soil. A digital image processing method was used to calculate the local deformations and local stresses for any region on the surface of triaxial soil specimens. The principle and implementation of this digital image processing method were introduced as well as the calculation method for local mechanical properties of soil specimens. Comparisons were made between the test results calculated by the data from both the entire specimen and local regions, and it was found that the deformations were more uniform in the middle region compared with the entire specimen. In order to quantify the nonuniform characteristic of deformation, the non-uniformity coefficients of strain were defined and calculated. Traditional and end-lubricated triaxial tests were conducted under the same condition to investigate the effects of using local region data for deformation calculation on eliminating the end restraint of specimens. After the statistical analysis of all test results, it was concluded that for the tested soil specimen with the size of 39.1 mm × 80 ram, the utilization of the middle 35 mm region of traditional specimens in data processing had a better effect on eliminating end restraint compared with end lubrication. Furthermore, the local data analysis in this paper was validated through the comparisons with the test results from other researchers.  相似文献   

10.
Objective:To investigate the effect of Anethum graveolens(AG) extracts on the mounting frequency,histology of testis and epididymis,and sperm physiology.Methods:Male rats induced by cold immobilization before treating with vehicle or AG extracts [50,150,and 450 mg/kg body weight(BW)] via gastric tube for consecutive 1,7,and 14 d were examined for mounting frequency,testicular phosphorylation level by immunoblotting,sperm concentration,sperm acrosome reaction,and histological structures of testis and epididymis,respectively.Results:AG(50 mg/kg BW) significantly increased the mounting frequency on Days 1 and 7 compared to the control group.Additionally,rat testis treated with 50 mg/kg BW AG showed high levels of phosphorylated proteins as compared with the control group.In histological analyses,AG extract did not affect the sperm concentration,acrosome reaction,and histological structures of testis and epididymis.Conclusions:AG extract enhances the aphrodisiac activity and is not harmful to sperm and male reproductive organs.  相似文献   

11.

Objective

The present study is designed to investigate the cellular expressions and immunolocalizations of three different nitric oxide synthase (NOS) isoforms and the related nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling pathway in the ovaries of neonatal and immature rats.

Methods

The ovaries were obtained from ICR (Institute for Cancer Research) female Sprague-Dawley rats at postnatal days 1, 5, 7, 10, and 19. Then we carried out the histologic examination, immunohistochemistry, measurement of NOS activity, and modifications within the NO/cGMP pathway.

Results

During postnatal days 1, 5, 7, 10, and 19, all three isoforms of NOS were mainly localized to the oocytes and expressed as a gradual increase in granulosa cells and theca cells within the growing follicle. The ovarian total NOS activities and NO levels were increased at postnatal days 7 and 10 compared with other days.

Conclusions

Our findings suggest that the locally produced NO and the NO/NOS signaling systems are involved in the follicular development to puberty.  相似文献   

12.

Objective

To investigate the beneficial effect of bicyclol on rat hearts subjected to ischemia-reperfusion (IR) injuries and its possible mechanism.

Methods

Male Sprague-Dawley rats were intragastrically administered with bicyclol (25, 50 or 100 mg/(kg·d)) for 3 d. Myocardial IR was produced by occlusion of the coronary artery for 1 h and reperfusion for 3 h. Left ventricular hemodynamics was continuously monitored. At the end of reperfusion, myocardial infarct was measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining, and serum lactate dehydrogenase (LDH) level and myocardial superoxide dismutase (SOD) activity were determined by spectrophotometry. Isolated ventricular myocytes from adult rats were exposed to 60 min anoxia and 30 min reoxygenation to simulate IR injuries. After reperfusion, cell viability was determined with trypan blue; reactive oxygen species (ROS) and mitochondrial membrane potential of the cardiomyocytes were measured with the fluorescent probe. The mitochondrial permeability transition pore (mPTP) opening induced by Ca2+ (200 μmol/L) was measured with the absorbance at 520 nm in the isolated myocardial mitochondria.

Results

Low dose of bicyclol (25 mg/(kg·d)) had no significant improving effect on all cardiac parameters, whereas pretreatment with high bicyclol markedly reduced the myocardial infarct and improved the left ventricular contractility in the myocardium exposed to IR (P<0.05). Medium dose of bicyclol (50 mg/(kg·d)) markedly improved the myocardial contractility, left ventricular myocyte viability, and SOD activity, as well decreased infarct size, serum LDH level, ROS production, and mitochondrial membrane potential in rat myocardium exposed to IR. The reduction of ventricular myocyte viability in IR group was inhibited by pretreatment with 50 and 100 mg/(kg·d) bicyclol (P<0.05 vs. IR), but not by 25 mg/(kg·d) bicyclol. The opening of mPTP evoked by Ca2+ was significantly inhibited by medium bicyclol.

Conclusions

Bicyclol exerts cardioprotection against IR injury, at least, via reducing oxidative stress and its subsequent mPTP opening.  相似文献   

13.

Objective

To evaluate the safety and effectiveness of rotational atherectomy followed by drug eluting stent (DES) implantation in patients with complex coronary lesions.

Methods

From August 2006 to August 2012, 253 consecutive patients with 289 lesions and who underwent rotational atherectomy in our center were enrolled in this study.

Results

The overall procedure success rate was 98% with the cost of two (0.8%) coronary perforations, three (1.2%) dissections, five (2.0%) slow flows or no flows, three (1.2%) peri-procedure myocardial infarctions, and two (0.8%) in hospital deaths. During follow-up (mean three years), one (0.4%) patient died, two (0.8%) patients had acute myocardial infarction, 14 (5.5%) had restenosis, and target lesion revascularization occurred in eight patients (3.2%).

Conclusions

Rotational atherectomy followed by DES implantation is a safe and effective technique for patients with complex coronary lesions, especially calcified and non-dilatable lesions.  相似文献   

14.
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   

15.

Objective

This study aims to investigate the degree of biocompatibility and neuroregeneration of a polymer tube, poly-3-hydroxyoctanoate (PHO) in nerve gap repair.

Methods

Forty Wistar Albino male rats were randomized into two groups: autologous nerve gap repair group and PHO tube repair group. In each group, a 10-mm right sciatic nerve defect was created and reconstructed accordingly. Neuroregeneration was studied by sciatic function index (SFI), electromyography, and immunohistochemical studies on Days 7, 21, 45 and 60 of implantation. Biocompatibility was analyzed by the capsule formation around the conduit. Biodegradation was analyzed by the molecular weight loss in vivo.

Results

Electrophysiological and histomorphometric assessments demonstrated neuroregeneration in both groups over time. In the experimental group, a straight alignment of the Schwann cells parallel to the axons was detected. However, autologous nerve graft seems to have a superior neuroregeneration compared to PHO grafts. Minor biodegradation was observed in PHO conduit at the end of 60 d.

Conclusions

Although neuroregeneration is detected in PHO grafts with minor degradation in 60 d, autologous nerve graft is found to be superior in axonal regeneration compared to PHO nerve tube grafts. PHO conduits were found to create minor inflammatory reaction in vivo, resulting in good soft tissue response.  相似文献   

16.

Objective

This study was aimed at assessing the dynamics of vitronectin (VN), laminin (LN), and heparan sulfate/heparin (HS/HP) content changes during experimental burn healing.

Methods

VN, LN, and HS/HP were isolated and purified from normal and injured skin of domestic pigs, on the 3rd, 5th, 10th, 15th, and 21st days following thermal damage. The wounds were treated with apitherapeutic agent (propolis), silver sulfadiazine (SSD), physiological salt solution, and propolis vehicle. VN and LN were quantified using an immunoenzymatic assay and HS/HP was estimated by densitometric analysis.

Results

Propolis treatment stimulated significant increases in VN, LN, and HS/HP contents during the initial phase of study, followed by a reduction in the estimated extracellular matrix molecules. Similar patterns, although less extreme, were observed after treatment with SSD.

Conclusions

The beneficial effects of propolis on experimental wounds make it a potential apitherapeutic agent in topical burn management.  相似文献   

17.

Objective

To screen mutations in FERM domain-containing protein 7 (FRMD7) gene in two Chinese families with X-linked idiopathic congenital nystagmus (XLICN).

Methods

Common ophthalmic data and peripheral blood of two Chinese XLICN families (families A and B) were collected after informed consent. Genomic DNA was prepared from the peripheral blood of members of the two families and from 100 normal controls. Mutations in the FRMD7 gene were determined by directly sequencing polymerase chain reaction (PCR) products.

Results

We identified a novel mutation c.980_983delATTA compound with c.986C>A mutation in the 11th exon of FRMD7 in family B, and a previously reported splicing mutation c.782G>C (p.R261G) in family A. The mutations were detected in patients and female carriers, while they were absent in other relatives or in the 100 normal controls.

Conclusions

Our results expand the spectrum of FRMD7 mutations in association with XLICN, and further confirm that the mutations of FRMD7 are the underlying molecular mechanism for XLICN.  相似文献   

18.
研究目的:探索小分子酪氨酸激酶抑制剂舒尼替尼(sunitinib)对结肠肿瘤微环境中的肿瘤相关成纤维细胞的作用及其机制。创新要点:舒尼替尼通过抑制肿瘤间质成纤维细胞的生长,间接发挥抗肿瘤效应,为结肠癌综合治疗的提供新途径。研究方法:通过细胞周期分析和细胞增殖测定进行舒尼替尼体外抑制肿瘤细胞的研究。采用Western-blot检测磷酸化血小板衍生生长因子β受体(PDGFR-β)、蛋白激酶B(Akt)及细胞外信号调节蛋白激酶(ERK)的蛋白水平。通过注射肠腺癌细胞株SW620和结肠成纤维细胞构建的裸鼠移植瘤模型来研究舒尼替尼的体内抑瘤效果。重要结论:舒尼替尼可有效抑制结肠癌来源的原代结肠成纤维细胞生长,该抑制作用主要通过抑制血小板衍生生长因子(PDGF)信号通路得以实现。  相似文献   

19.

Objective

Numerous studies examining the relationship between human epidermal growth factor receptor 2 (HER-2) overexpression and survival in patients with colorectal cancer (CRC) have yielded controversial results. We therefore performed a meta-analysis more precisely to estimate its prognostic value.

Methods

Published studies investigating the effect of HER-2 overexpression on CRC survival were identified; the hazard ratios (HRs) and their corresponding 95% confidence intervals (95% CIs) were pooled in terms of disease-specific or overall survival.

Results

Eleven studies were included in the meta-analysis. The pooled data showed that HER-2 overexpression was negatively related to CRC survival (HR=1.10, 95% CI: 0.77–1.44). Subgroup analyses regarding test method and study quality also demonstrated little association between HER-2 overexpression and CRC survival (HR=0.89, 95% CI: 0.50–1.29; HR=0.90, 95% CI: 0.43–1.37, respectively).

Conclusions

Regardless of several limitations, our study suggested that HER-2 overexpression probably had little impact on CRC survival.  相似文献   

20.

Objective

To reevaluate whether relatively few oocytes obtained in one cycle are an indication for intracytoplasmic sperm injection (ICSI).

Methods

A total of 406 cycles with three or fewer retrieved oocytes performed in 396 non-male infertile couples were retrospectively reviewed. Cycles were classified into three groups by different fertilization techniques: the in vitro fertilization (IVF) group, insemination with conventional IVF; the ICSI group, insemination with ICSI though semen parameters were normal; and the rescue ICSI group, re-insemination with ICSI after conventional IVF failure.

Results

The ICSI group resulted in higher normal fertilization compared with the conventional IVF group. Correspondingly, the cycle cancellation rate was decreased in the ICSI group, though it was not statistically significant. The clinical pregnancy rate and implantation rate were lower in the ICSI group compared with the conventional IVF group. Rescue ICSI was a method to avert total fertilization failure in conventional IVF, increasing fertilization and ensuring embryo availability for transfer, but the normal fertilization was the lowest due to delayed insemination and the chance of pregnancy was very little.

Conclusions

Obtaining only few oocytes in one cycle is not considered as an indication for ICSI when the sperm sample is apparently normal. Rescue ICSI is either not recommended if conventional insemination fails. Such patients should not be subjected to the unnecessary costs and potential risks of ICSI.  相似文献   

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