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991.
Activation of central GABAB receptors offsets the cyclosporine counteraction of endotoxic cardiovascular outcomes in conscious rats 下载免费PDF全文
Marwa Y. Sallam Sahar M. El‐Gowilly Abdel‐Galil A. Abdel‐Galil Mahmoud M. El‐Mas 《Fundamental & clinical pharmacology》2018,32(5):485-498
We have previously shown that cyclosporine (CSA) counteracts cardiovascular manifestations induced by endotoxemia (lipopolysaccharide, LPS) such as hypotension and cardiac autonomic dysfunction in conscious rats. In this study, we investigated whether the facilitation of central γ‐amino butyric acid (GABA) neurotransmission blunts these favorable influences of CSA. The LPS‐CSA interaction was determined in the absence and presence of drugs that activate GABAA or GABAB receptors or elevate synaptic GABA levels in the central nervous system. The consequent i.v. administration of CSA (10 mg/kg) blunted the LPS‐evoked hypotension, tachycardia, and reductions in time‐ and frequency‐domain indices of heart rate variability (measures of cardiac autonomic control) evoked by LPS (10 mg/kg i.v.). The ability of CSA to reverse the LPS effects disappeared in rats treated intracisternally (i.c.) with baclofen (selective GABAB agonist, 2 μg/rat) but not muscimol (selective GABAA agonist, 1 μg/rat), indicating a preferential compromising action for central GABAB receptors on the advantageous effects of CSA. Moreover, the improvement by CSA of LPS‐evoked cardiovascular derangements was also eliminated after concurrent i.c. administration of vigabatrin (GABA transaminase inhibitor, 200 μg/rat) or tiagabine (GABA reuptake inhibitor, 100 μg/rat). These results demonstrate that the activation of central GABAB receptors either directly via baclofen or indirectly following interventions that boost GABA levels in central synapses counterbalances the rectifying action of CSA on endotoxemia. 相似文献
992.
Naibijiang Maolakuerban Baihetiya Azhati Hamulati Tusong Asimujiang Abula Anniwaer Yasheng 《Cancer biology & therapy》2018,19(4):282-291
In this study, we investigated the mechanism of miR-200c-3p and SLC6A1 in regulating cell activity of clear cell renal cell carcinoma (CCRCC). The mRNA and miRNA expressions of tissue specimens were analyzed by CapitalBio Corporation (Beijing, China). The expression of SLC6A1 in CCRCC cells was examined through qRT-PCR and western blot. The migration and invasion ability of 786-O cells was testified by transwell assay after transfected. 786-O cell proliferation ability was detected by MTT assay. Dual luciferase reporter assay verified the association between SLC6A1 and miR-200c-3p. SLC6A1 was high expressed and miR-200c-3p was low expressed in CCRCC tissues and cells. Besides, lower SLC6A1 expression indicated longer survival time and higher survival rate. MiR-200c-3p could directly target at SLC6A1 and reduce its expression. MiR-200c-3p inhibited the proliferation, migration and invasion in 786-O cells by down-regulating SLC6A1 expression. The results suggested that the miR-200c-3p served as a suppressor for CCRCC via down-regulating SLC6A1. 相似文献
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994.
Heart Rate and Bone Mineral Density in Older Women with Hypertension: Results from the Korea National Health and Nutritional Examination Survey 下载免费PDF全文
995.
王凯 《中华医院感染学杂志》2013,23(1):187-189
目的 了解医院2010年1月-2011年6月阴沟肠杆菌的临床分布及耐药性分析,为临床合理用药提供依据.方法 从近年来感染标本中分离出阴沟肠杆菌,采用法国生物梅里埃公司VITEK-2 Compact全自动细菌分析仪对所分离的菌株进行鉴定和药敏试验,采用WHONET5.4软件进行统计分析.结果 分离的123株阴沟肠杆菌主要来自于肝胆外科、ICU等科室,标本主要来源于痰液、胆汁及尿液中;阴沟肠杆菌对亚胺培南、美罗培南、厄他培南、阿米卡星等有较好的抗菌活性,敏感率依次为99.19%、99.19%、94.31%、94.31%;而对头孢西丁、头孢唑林、氨苄西林/舒巴坦、头孢替坦、氨苄西林的敏感性较差,敏感率依次为1.63%、1.63%、4.88%、4.88%和4.07%.结论 临床分离的阴沟肠杆菌耐药现象比较严重,应加强耐药性监测,以指导临床合理用药,控制医院感染. 相似文献
996.
The counting process with a Cox‐type intensity function has been extensively applied to analyze recurrent event data, which assume that the underlying counting process is a time‐transformed Poisson process and that the covariates have multiplicative or additive effects on the mean and rate functions of the counting process. The existing statistical inference, however, often encounters difficulties due to high‐dimensional covariates, such as in gene expression and single nucleotide polymorphism data that have revolutionized our understanding of cancer recurrence and other diseases. In this paper, a technique of sufficient dimension reduction is applied to the mean and rate function for the number of occurrences of events over time. A two‐step procedure is proposed to estimate the model components: first, a nonparametric estimator is proposed for the baseline, and then the basis of the central subspace and its dimension are estimated through a modified slicing inverse regression. On the basis of the estimated structural dimension and on the basis of the central subspace, we can estimate the regression function by using the local linear regression. A simulation is performed to confirm and assess the theoretical findings, and an application is demonstrated on a set of chronic granulomatous disease data. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
997.
目的:分析比较外周静脉留置针穿刺采血与直接静脉穿刺采血血培养标本污染发生率。方法对儿科病房2012年4月~2013年9月送检的血培养标本结果进行回顾性调查,比较两种不同方法采集血培养标本发生的污染率。结果3016份送检的血培养标本中,判断为污染菌的有67例,总污染率为2.2%。外周静脉留置针穿刺采血594例,判断为污染12例,污染率为2.0%;直接静脉穿刺采血2422例,判断为污染54例,污染率2.2%。结论外周静脉留置针穿刺采血与直接静脉穿刺采血,血培养标本污染的发生率差异无显著意义。儿科血培养的采集可以在新置入的外周静脉留置针内采血。 相似文献
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1000.
《Medical engineering & physics》2014,36(1):129-135
This paper develops a method for semi-automatic detection of breast lesion boundaries by combining the snake evolution techniques with statistical texture information of images. We propose an efficient image energy function in segmentation based on image features, first-order textural features and four n × n masks. The segmentation results were evaluated by using area error rate. The image features were evaluated qualitatively by using the contrast-to-noise ratio and fractal dimension analysis. In our study, standard deviation, skewness and entropy are indicated as being the most relevant image features. 相似文献