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1.
INTRODUCTION Pulmonary hypertension is not rare in humanwith some heart and lung diseases. Chronic pul-monary hypertension leads to structural alterationsof the lung vessels. The pathophysiology of thisremodeling process is still poorly understood.Furthermore, the structural damage of the lungvessels limits the clinical success of vasodilatortreatment. Assuming genetic susceptibility, shearstress and inflammation are the principal pathoge-netic factors involved in lung vessel remode…  相似文献   

2.
目的营养支持对慢性阻塞性肺部疾病患者血气和肺功能的影响。方法选择43例患者使用抗感染、平喘、化痰等常规治疗,并与43例进行有效营养支持的患者比较,治疗后1月血气分析以及肺功能的变化情况。结果治疗后观察组PO2和PCO2均达到正常范围,且PO2高于对照组（P〈0.05）,PCO2低于对照组（P〈0.05）,治疗后观察组患者FVC显著较对照组提高（P〈0.05）,且FEV1/FVC随之升高（P〈0.05）,同时FEV1%显著高于对照组（P〈0.05）。结论营养不良对于慢性阻塞性肺部疾病患者是一种疾病恶化的因素,进行有效的营养支持能改善患者血气分析结果,提高患者肺功能,值得临床重视。  相似文献   

3.
INTRODUCTION Transformation, proliferation and migration of vascular smooth muscle cells (VSMCs) into en- domembrane of arteries are the pathological mani- festations of atherosclerosis. Gap junction (GJ) and connexin (Cx) situated between endothelial cells play an important role in this process. Currently, connexin between VSMCs that have been recognized at protein molecular level includes Cx40, Cx43, and Cx37 (Li and Simardm, 1999). It showed that the occurrence of arteriosclerosi…  相似文献   

4.
In this study, we examined the expression of inducible nitric oxide synthase (iNOS) and vascular endothelial growth factor (VEGF) by immunohistochemical staining in 76 tissue sections collected from hepatocellular carcinoma (HCC) patients undergoing hepatectomy. Microvascular density (MVD) was determined by counting endothelial cells immunostained using anti-CD34 antibody. We performed DNA-flow cytometric analyses to elucidate the impact of iNOS and VEGF expression on the cell cycle of HCC. Most of the HCC cells that invaded stroma were markedly immunostained by iNOS antibody. The iNOS stain intensity of the liver tissue close to the tumor edge was stronger than that of HCC tissue, and the strongest was the hepatocytes closer to the tumor tissue. However, iNOS expression in 10 normal hepatic samples was undetectable. VEGF positive expression ratio was 84.8% in iNOS positive expression cases, and the ratio was 35.3% in negative cases. There was significant correlation (P=0.000) between iNOS and VEGF expression. Moreover, iNOS expression was significantly associated with bcl-2 and MVD, but without p53 expression. DNA-flow cytometric analyses showed that combined expression of iNOS and VEGF had significant impact on the cell cycle in HCC. PI (Proliferating Index) and SPF (S-phase fraction) in the combined positive expression of iNOS and VEGF group was significantly higher than that in the combined negative group. The present findings suggested that iNOS expression was significantly associated with angiogenesis, bcl-2 and cell proliferation of HCC. Project supported in part by the National Ninth-Five-Years Project Fund (No. 96909121), China  相似文献   

5.
采用热缩聚法以L-天冬氨酸为原料合成了聚天冬氨酸（PASP）,并采用失重法与极化曲线法研究了在中性水体系中PASP对A3钢的缓蚀性能。实验结果表明,PASP对A3钢有较好的缓蚀作用,在该体系中是以抑制阳极为主的吸附型缓蚀剂,与抗坏血酸复配有协同作用,缓蚀效果最高达90%以上。  相似文献   

6.
ＩＮＴＲＯＤＵＣＴＩＯＮＮｉｔｒｉｃｏｘｉｄｅ (ＮＯ) ,ａｓｈｏｒｔｈａｌｆ ｌｉｆｅｒａｄｉｃａｌ,ｉｓｈｉｇｈｌｙｒｅａｃｔｉｖｅ ,ａｎｄｉｓｉｎｖｏｌｖｅｄｉｎｍａｎｙｂｉｏ ｌｏｇｉｃａｌｐｒｏｃｅｓｓｅｓ,Ｉｔｓｅｅｍｓｔｏｐｌａｙａｎｉｍｐｏｒｔａ  相似文献   

7.
Plexiform lesions (PLs), which are often accompanied by perivascular infiltrates of mononuclear cells, represent the hallmark lesions of pulmonary arteries in humans suffering from severe pulmonary arterial hypertension (PAH). Endothelial progenitor cells (EPCs) have been recently implicated in the formation of PLs in human patients. PLs rarely develop in rodent animal models of PAH but can develop spontaneously in broiler chickens. The aim of the present study was to confirm the presence of EPCs in the PLs in broilers. The immune mechanisms involved in EPC dysfunction were also evaluated. Lungs were collected from commercial broilers at 1 to 4 weeks of age. The right/total ventricle ratios indicated normal pulmonary arterial pressures for all sampled birds. Immunohistochemistry was performed to determine the expressions of EPC markers (CD133 and VEGFR-2) and proangiogenic molecule hepatocyte growth factor (HGF) in the lung samples. An EPC/lymphocyte co-culture system was used to investigate the functional changes of EPCs under the challenge of immune cells. PLs with different cellular composition were detected in the lungs of broilers regardless of age, and they were commonly surrounded by moderate to dense perivascular mononuclear cell infiltrates. Immunohistochemical analyses revealed the presence of CD133+ and VEGFR-2+ cells in PLs. These structures also exhibited a strong expression of HGF. Lymphocyte co-culture enhanced EPC apoptosis and completely blocked HGF-stimulated EPC survival and in vitro tube formation. Taken together, this work provides evidence for the involvement of EPCs in the development of PLs in broilers. It is suggested that the local immune cell infiltrate might serve as a contributor to EPC dysfunction by inducing EPC death and limiting their response to angiogenic stimuli. Broiler chickens may be valuable for investigating reversibility of plexogenic arteriopathy using genemodified inflammation-resistant EPCs.  相似文献   

8.
INTRODUCTION Bronchioloalveolar carcinoma (BAC) is a par-ticular subtype of pulmonary adenocarcinoma de-rived from clara cell and type II pneumocyte. BAC cells grow along and within alveolar spaces while the alveolar framework of the lung is preserved. The incidence of BAC appears to be rising recently. The etiology and pathogenesis of this unique neoplastic disease are still unclear; many studies of oncogene and tumor suppressor gene expression include BAC with all adenocarcinoma o…  相似文献   

9.
Objective: To assess the effect of angiotensin Ⅱ type 1 (AT1) receptor antagonist losartan on myocardium connexin43 (Cx43) gap junction (GJ) expression in spontaneously hypertensive rats (SHRs) and investigate possible mechanisms. Methods: Sixteen 9-week-old male SHRs and 8 age-matched male Wistar-Kyoto (WKY) rats were included in this study. SHRs were randomly divided into two groups to receive losartan at 30mg/(kg·d) by oral gavage once daily for 8 weeks (SHR-L) or vehicle (0.9% saline) to act as controls (SHR-V); WKY rats receiving vehicle for 8 weeks served as normotensive controls. At the end of the experiment, rats were sacrificed and the hearts were removed. Expressions of Cx43 and nuclear factor-kappaB p65 (NF-κB p65) proteins in all three groups were observed and further investigations on the effect of angiotensin Ⅱ type 1 receptor antagonist losartan (30mg/(kg·d), 8 weeks) on Cx43 expression were conducted with Western blot and immunohistochemistry. NF-κB p65 protein in nuclear extracts was determined by Western blot. Results: Left ventricular (LV) hypertrophy was prominent in SHRs, Cx43 and NF-κB p65 protein expressions were obviously upregulated and Cx43 distribution was dispersed over the cell surface. Treatment with losarton reduced the over-expressions of Cx43 and NF-κB p65 in LV myocardium. The distribution of Cx43 gap junction also became much regular and confined to intercalated disk after losartan treatment. Conclusion: Cx43 level was upregulated in LV myocardium of SHR during early stage of hypertrophy. Angiotensin Ⅱ type l receptor antagonist losartan prevented Cx43 gap junction remodeling in hypertrophied left ventricles, possibly through the NF-κB pathway.  相似文献   

10.
基于静态阻垢实验系统,研究了聚天冬氨酸的阻垢性能,探讨了钙离子浓度、时间、温度以及pH值对其阻垢性能的影响,通过红外光谱和热重分析对聚天冬氨酸进行表征,并在过冷沸腾传热装置中实验验证了聚天冬氨酸的抗垢性能。实验结果表明：聚天冬氨酸可耐高温、热稳定性好．可应用于高温水处理系统和高钙离子浓度水处理系统,适用于工业锅炉水处理及供暖水处理系统。  相似文献   

11.
Background:Bone marrow mesenehymal stem cell(MSC)transplantation is a promising strategy in the treatment of myocardial infarction(MI).However,the time for transplanting cells remains controversial.The aim of this study was to find an optimal time point for cell transplantation.Methods:MSCs were isolated and cultured from Sprague-Dawley(SD) rats.MI model was set up in SD rats by permanent ligation of left anterior descending coronary artery.MSCs were directly injected into the infarct berder zone at 1 h,1 week and 2 weeks after MI,respectively.Sham-operated and MI centrel groups received equal volume of phosphate buffered saline(PBS).At 4 weeks after MI,cardiac function Was assessed by echocardiography;vessel density Was analyzed on hematoxylin-eosin stained slides by light microscopy;the apoptosis of cardiomyocytes Was evaluated by terminal deoxynucleotidy1 transferase-mediated dUTP nick end-labeling(TUNEL) assay;the expressions of proteins were analyzed by Western blot.Results:MSC transplantation improved cardiac function.reduced the apoptosis of cardiomyocytes and increased vessel density.These benefits were more obvious in l-week group than in 1-h and 2-week groups.There are more obvious increases in the ratio of bc1-2/bax and the expression of vascular endothelial growth factor(VEGF)and more obvious decreases in the expression of cleaved-caspase-3 in 1-week group than those in other two groups.Conclusion:MSC transplantation was beneficial for the recovery of cardiac function.MSC transplantation at l week post-MI exerted the best effects on increases of cardiac function,anti-apoptosis and angiogenesis.  相似文献   

12.
Purpose: To investigate the relationship between expression of cell cycle-related protein cyclin D1, p27kipl and the pathogenesis of bronchioloalveolar carcinoma (BAC) and the value of prediction of prognosis. Methods: Cyclin D 1 and p27kip 1 protein were detected by immunohistochemical En Vision method in 43 BACs. Results: The positivity of cyclin D 1 in BAC was 65.1% (28/43), which was significantly higher than that in normal pulmonary tissue (0/13), P＜0.01. No statistically significant association was found between cyclin D1 expression data and sex, age, tobacco-use history, histologic subtype (mucinous vs nonmucinous), stromal fibrosis, lymph node metastasis, clinical stage or postoperative survival period (P＞0.05), while cyclin D1 expression was found to be negatively correlated with tumor size (P＜0.05). The positivity of p27kipl in BACs was 51.2% (22/43), significantly lower than that in normal pulmonary tissue (12/13), P＜0.01. p27kipl expression level was not associated with sex, age, tobacco-use history, tumor size or histologic subtype (P＞0.05), but was negatively correlated with stromal fibrosis, lymph node metastasis and clinical stage (P＜0.05); and positively associated with postoperative survival period (P＜0.01). The survival rate of p27kipl positive group was significantly higher than that of p27kipl negative group (P＜0.01). No statistically significant correlation was found between cyclin D 1 and p27kipl expression. Conclusions: Increased cyclin D1 expression and decreased p27kip 1 expression are related to the pathogenesis of BAC;decreased p27kipl expression is associated with metastasis progression; immunodetection ofp27kip 1 is useful for assessment of prognosis.  相似文献   

13.
Abstract

In this study, we sought to understand how Black lives matter (BLM) epistemology, as displayed through six months of social media content from official accounts, can inform a racially liberatory pedagogy in higher education for Black and other racially minoritized students. We found BLM, through Facebook and Twitter, situated intersectional Black culture in the contemporary struggle for liberation. BLM also offered information that can raise its followers’ intersectional critical consciousness. Additionally, BLM content highlighted actions that can support Black liberation. Lastly, BLM content supported the building of relationships and naming of emotions as Black people work toward their liberation. In this sense, BLM connected with elements of a racially liberatory pedagogy and offered nuances that advanced the framework. We discuss the implications of this framework for teaching in higher education.  相似文献   

14.
Background： Endothelial and smooth muscle cells were used as seeding cells and heterogeneous acellularized matrix was used as scaffold to construct the tissue-engineered graft. Methods： A 2 weeks piglet was selected as a donor of seeding cells. Two-centimetre length of common carotid artery was dissected. Endothelial cells and smooth muscle cells were harvested by trypsin and collagenase digestion respectively. The isolated cells were cultured and expanded using routine cell culture technique. An adult sheep was used as a donor of acellularized matrix. The thoracic aorta was harvested and processed by a multi-step decellularizing technique to remove the original cells and preserve the elastic and collagen fibers. The cultured smooth muscle cells and endothelial cells were then seeded to the acellularized matrix and incubated in vitro for another 2 weeks. The cell seeded graft was then transplanted to the cell-donated piglet to substitute part of the native pulmonary artery. Results： The cultured cells from piglet were characterized as endothelial cells by the presence of specific antigens vWF and CD31, and smooth muscle cells by the presence of specific antigen a-actin on the cell surface respectively with immunohistochemical technique. After decellularizing processing for the thoracic aorta from sheep, all the cellular components were extracted and elastic and collagen fibers kept their original morphology and structure. The maximal load of acellular matrix was decreased and 20% lower than that of untreated thoracic aorta, but the maximal tensions between them were not different statistically and they had similar load-tension curves. Three months after transplantation, the animal was sacrificed and the graft was removed for observation. The results showed that the inner surfaces of the graft were smooth, without thrombosis and calcification. Under microscopy, a great number of growing cells could be seen and elastic and collagen fibers were abundant. Conclusion： Cultured self-derived endothelial and smooth muscle cells could be used as seeding cells and heterogeneous acellularized matrix could be used as scaffold in constructing tissue-engineered graft.  相似文献   

15.
类脂双层研究的动力来自动物世界,1961年首次报道了生物体的双层类脂膜(BLM)自组装.BLM体系已广泛应用于对生物能、光合成、免疫学和生物传感器等多种物理学现象的研究.文章在综述了类脂双层的起源及形成机理的基础上,从理论上分析了类脂双层的电学参量,以及类脂双层应用于生物传感器的应用前景.  相似文献   

16.
This article describes a representation formed by a waltzing couple of two students that can be used to teach the asymmetrical anatomical relationships among the trachea, bronchi, pulmonary trunk, and the pulmonary arteries in the mediastinum.  相似文献   

17.
目的:探讨在急性肺损伤(ALI)中酸敏感离子通道(ASIC3)的表达变化及其与ALI的关系。方法:24只雄性SD大鼠随机分为四组,LPS2h,4h,6h和对照组;以内毒素持续静脉注射复制大鼠急性肺损伤模型,急性肺损伤后2h、4h、6h时采集标本监测动脉血气、肺湿/干比、肺组织病理、免疫组化检测ASIC3在肺内的表达情况。结果急性肺损伤后4h,6h肺泡上皮细胞内ASIC3的表达明显高于对照组(P<0.05),LPS2h组和对照组相比无明显差异;肺的湿/干比LPS2h,4h和对照组相比无显著差异(P>0.05),LPS6h组明显高于对照组(P<0.05)。结论1大鼠肺泡上皮细胞和支气管粘膜上皮有ASIC3的表达;2急性肺损伤大鼠肺泡表面的ASIC3表达增多。  相似文献   

18.
Abstract

Popular media shapes societal perceptions and discourse. The growing use of news media in higher education practices (outreach, admissions, and campus communication) have heightened the need for institutional leadership to not only understand the general impact of popular media but also to comprehend students’ representation, as well as the acquisition and dissemination of media content. In this study, authors present a media content analysis of newspaper coverage of the Black Lives Matter (BLM) movement in the well-known periodical, the Chronicle of Higher Education. Ultimately, this study demonstrates (1) organizational leadership can be influenced and disrupted to promote racial justice and (2) the discursive treatment of the BLM in popular media and, and by extension, in the United States’ public imagination. Overall, this study suggests that in situations where institutional policies perpetuate racial inequity, BLM student movements have the capacity to complicate existing discourse about Blackness in higher education and catalyze substantial social change.  相似文献   

19.
Objective: To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide (G4PAMAMNEGFASODN) compound on the expressions of vascular endothelial growth factor (VEGF) and its mRNA of breast cancer cells and on the inhibition of vascular endothelial cells. Methods: We examined the morphology of G4PAMAM/VEGFASODN compound and its pH stability, in vitro transfection efficiency and toxicity, and the expressions of VEGF and its mRNA. Methyl thiazolyl tetrazolium assay was used to detect the inhibitory function of the compound on vascular endothelial cells. Results: The compound was about 10 nm in diameter and was homogeneously netlike. From pH 5 to 10, it showed quite a buffered ability. The 48-h transfection rate in the charge ratio of 1:40 was 98.76%, significantly higher than that of the liposome group (P<0.05). None of the transfection products showed obvious toxicity on the cells. The expressions of both VEGF protein and its mRNA after G4PAMAM/VEGFASODN transfection decreased markedly. Conclusion: With a low toxicity, high safety, and high transfection rate, G4PAMAMNEGFASODN could be a promising gene vector. Specifically, it inhibits VEGF gene expression efficiently, laying a basis for further in vivo animal studies.  相似文献   

20.
建立液态甲醛诱导小鼠肝损伤及其纤维化模型,并初步观察小鼠肝组织的病变过程．将正常昆明小鼠随机分为实验组和对照组．实验组小鼠注射15％的甲醛溶液,注射量为1mL／kg,每周注射两次,并且每天用1％的甲醛溶液喂养．对照组小鼠以纯净水正常喂养,分别在实验开始后的第3、6、8周处死实验组小鼠各4只,肉眼及病理切片观察其肝脏形态的改变,发现小鼠的体重均呈增长趋势．与实验组小鼠比较,对照组小鼠体重增长显著（P〈0．05）．第8周小鼠肝脏出现明显的病变,表面粗糙,颜色暗黄,出现深色斑点．在石蜡切片中可观察到肝脏组织变得松散,窦周隙（Disse’s space）增大．肝星状细胞（hepatic stellate cell,HSC）较对照组明显增多．随着甲醛处理时间的延长,HSC不同程度地增多,肝损伤病变程度越来越严重．  相似文献   

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