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排序方式: 共有359条查询结果,搜索用时 15 毫秒
1.
17β-雌二醇对大鼠脊髓损伤后神经保护作用的研究 总被引:1,自引:0,他引:1
目的:探讨17β-雌二醇(E2)对大鼠脊髓损伤(SCI)后的神经保护作用及其机制。方法:应用改良的Allen′s重物打击法建立大鼠急性脊髓损伤模型,将大鼠随机分为两组:A组(PBS对照组)和B组(E2治疗组),每组42只,B组造模成功后15min及24h腹腔注射E2(4.0mg/kg,以PBS溶解),A组在相同时间给予等量无菌PBS。分别于伤后7d、14d、21d及28d,应用改良Tarlov评分法和Rivlin斜板试验评价大鼠脊髓神经功能恢复情况。于伤后6h、24h、3d、7d、14d及28d时处死动物,以损伤部位为中心取材,HE染色观察脊髓组织病理变化,TUNEL法染色检测细胞凋亡,免疫组化染色检测caspase-3、Bcl-2的表达情况。结果:从伤后14d起,B组Tarlov评分和斜板试验角度与A组相比差异有显著性(P〈0.01)。TUNEL法检测表明,大鼠SCI后存在细胞凋亡,3d时达高峰,与caspase-3的表达基本一致,B组伤后24h、3d及7d时凋亡细胞比率显著低于A组(P〈0.01或P〈0.05)。免疫组化结果显示B组伤后24h、3d、7d、14d及28d时caspase-3表达低于A组(P〈0.01或P〈0.05),而Bcl-2表达高于A组(P〈0.01或P〈0.05)。结论:E2能促进大鼠SCI后的神经功能恢复,具有一定的神经保护作用;E2可能是通过减少SCI后继发性细胞凋亡的机制发挥作用的。 相似文献
2.
Zubin Bhagwagar Andrew J Montgomery Paul M Grasby Philip J Cowen 《Neuropsychopharmacology》2003,54(9):890-895
BACKGROUND: Elevated cortisol levels might account for the reduction in central serotonin 1A (5-hydroxytryptamine [5-HT](1A)) receptor binding and function observed in patients with major depression. We tested this hypothesis by studying the effect of acute administration of hydrocortisone on 5-HT(1A) receptor binding potential (BP) in subjects recovered from depression. METHODS: We studied 14 subjects (8 male, 6 female) who had recovered from at least two episodes of major depression and had been euthymic and drug free for at least 6 months. Serotonin 1A receptor BP was measured by [(11)C]WAY-100635 in conjunction with positron emission tomography. Subjects were tested on two occasions in a double-blind, random-order, crossover design after administration of either hydrocortisone (100 mg orally) or placebo 12 hours previously. Positron emission tomography scans were analyzed with a region of interest analysis. RESULTS: Hydrocortisone treatment did not decrease 5-HT(1A) receptor BP either in the hippocampus, which was our a priori hypothesis, or in other cortical 5-HT(1A) regions; however, female subjects had a higher 5-HT(1A) receptor BP in certain brain areas compared with male subjects. CONCLUSIONS: These data are consistent with an earlier study in healthy volunteers and do not support the proposal that decreased 5-HT(1A) receptor BP in patients with acute major depression is a consequence of cortisol hypersecretion. 相似文献
3.
A late positive-going component (P3) of the average evoked potential recorded from human scalp was shown to be quantitatively related to a priori stimulus probability both when the S was told the identity of the stimulus before it was presented and when the S was not told, and was instructed to guess. In the guessing situation, the amplitude of P3 was much larger and was influenced not only by the a priori probability of events determined by the experimenter but also by the interaction of these probabilities with the S's guessing behavior. The amplitude of the late positive component was inversely related to the proportion of trials in which a particular event was associated with a particular guess, i.e., the proportion of hits and misses. It was larger the more unexpected the outcome of the guess. This relationship held for different methods of manipulating the probability of two events. 相似文献
4.
5.
Richard E Overman Cory N Criss Zubin J Modi Samir K Gadepalli 《Journal of pediatric surgery》2021,56(2):328-331
IntroductionAutosomal recessive polycystic kidney disease (ARPKD) is a rare cause of renal failure with a highly variable clinical course. Patients who are symptomatic early in life frequently require early nephrectomy and peritoneal dialysis. In these patients there are little data to guide clinicians on whether to select unilateral nephrectomy or bilateral nephrectomy at the initial operative intervention. We review our experience with this disease process.MethodsA retrospective review was performed of 11 patients at our institution with ARPKD symptomatic within the first month of life. Charts were reviewed for relevant clinical data, and patients were divided into groups based on undergoing either unilateral or bilateral nephrectomy at their initial intervention. The decision for unilateral versus bilateral nephrectomy was decided by the clinical team without any available guidelines.ResultsOf the 11 patients reviewed, two patients died within the first two weeks from other complications. The remaining 9 all required nephrectomy, with 5 undergoing synchronous bilateral nephrectomy, and 4 undergoing initial unilateral nephrectomy. All four patients required removal of their contralateral kidney, a median of 25.5 days later. There was no difference in mortality, ventilator free days, or time to full feeds between the two groups, although the group undergoing initial unilateral nephrectomy had more TPN days than their counterparts (28 vs 17 days, p = 0.014).ConclusionsIn our cohort, there were few significant differences between the groups based on choice of initial unilateral or bilateral nephrectomy, and all children ultimately required removal of both kidneys. These data suggest that anesthetic exposures and other clinical outcomes might be optimized by initial bilateral nephrectomy.Level of evidenceIII. 相似文献
6.
Tryptophan depletion alters the decision-making of healthy volunteers through altered processing of reward cues. 总被引:7,自引:0,他引:7
Robert D Rogers Elizabeth M Tunbridge Zubin Bhagwagar Wayne C Drevets Barbara J Sahakian Cameron S Carter 《Neuropsychopharmacology》2003,28(1):153-162
While accumulating evidence suggests that effective real-life decision-making depends upon the functioning of the orbitofrontal cortex, much less is known about the involvement of the monoamine neurotransmitter systems and, in particular, serotonin. In the present study, we explored the impact of depleting the serotonin precursor, tryptophan, on human decision-making. Eighteen healthy volunteers consumed an amino-acid drink containing tryptophan and 18 healthy volunteers consumed an amino-acid drink without tryptophan, before choosing between simultaneously presented gambles, differing in the magnitude of expected gains (ie reward), the magnitude of expected losses (ie punishment), and the probabilities with which these outcomes were delivered. Volunteers also chose between gambles probing identified non-nomative biases in human decision-making, namely, risk-aversion when choosing between gains and risk-seeking when choosing between losses. Tryptophan-depleted volunteers showed reduced discrimination between magnitudes of expected gains associated with different choices. There was little evidence that tryptophan depletion was associated with altered discrimination between the magnitudes of expected losses, or altered discrimination between the relative probabilities with which these positive or negative outcomes were delivered. Risk-averse and risk-seeking biases were also unchanged. These results suggest that serotonin mediates decision-making in healthy volunteers by modulating the processing of reward cues, perhaps represented within the orbitofrontal cortex. It is possible that such a change in the cognition mediating human choice is one mechanism associated with the onset and maintenance of anhedonia and lowered mood in psychiatric illness. 相似文献
7.
目的 探讨反义端粒酶肽核酸 (PNA)片段对肺癌细胞株端粒酶活性及细胞株生长的抑制作用。方法 将人工合成的端粒酶反义PNA片段 ,应用脂质体转染法将反义端粒酶序列导入肺腺癌细胞株A5 49及小细胞癌细胞株NCI H44 6中 ,采用MTT法检测活细胞数 ,采用RT PCR ELLISA法检测端粒酶活性。结果 转染 72h后 ,A5 49、NCI H 44 6细胞株端粒酶活性 (A45 0值 )分别由 0 .5 82± 0 .0 3 9和 0 .5 71± 0 .0 43降低至 0 .2 94± 0 .0 48(P <0 .0 1)和 0 .2 76± 0 .0 5 1(P <0 .0 1) ;而两细胞株的活细胞数 (A5 80值 )分别由 0 .485± 0 .0 0 9和 0 .5 13± 0 .0 15降低至 0 .191± 0 .0 2 7(P <0 .0 1)和 0 .13 8± 0 .0 46(P <0 .0 1) ,细胞生长受到显著抑制。结论 反义端粒酶PNA片段具有抑制肺癌细胞株端粒酶活性的作用 ,并可抑制肺癌细胞的生长 相似文献
8.
目的 探讨抑郁症患者血清半乳糖凝集素-3(Galectin-3)、神经轴突导向因子-1(Netrin-1)、白介素-33(IL-33)水平表达,分析其与患者认知功能损害的关系.方法 选取2016年1月至2019年12月我科收治的抑郁症患者130例作为研究对象(抑郁症组).同期,另选取我院体检健康志愿者100例(对照组)... 相似文献
9.
Joseph Zubin 《Psychiatry》2013,76(2):237-247
10.
Maheshkumar N Upasani Supriya Chopra Reena Engineer Umesh Mahantshetty Seema Medhi Zubin Mehta Shyam K Shrivastava 《The British journal of radiology》2015,88(1054)