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31.
The expression of BAX in carotid atherosclcrosis and its regulation is far from defined. Objectives To investigate BAX expression in stable/fibrous and instable/vulnerable carotid plaque and its clinical significance. Methods 25 cases of carotid plaque specimens obtained from endarterectomy were divided into two groups, stable/fibrous 14 cases, vulnerable/instable 11 cases; aortic artery and its branches from hepatic transplantation donors 6 case as control. The expression of proapoptotic BAX was detected by immunohistochemistry (IHC), in situ hybridization(ISH) and in situ TdT dUTP nick end labeling (TUNEL). Results 5 eases of BAX ( ) were detected by ICH and ISH, 4 case of TUNEL ( ) were detected by TUNEL in stable/fibrous carotid plaque, while 10 cases were BAX ( )by IHC(P<0.05) , 11 case by ISH and 9 case by TUNEL were detected in instable/vulnerable carotid plaque (P<0.01), respectively. The intensity of BAX ( ) cells by IHC and ISH was 8.63±2.62 and 10.32±3.12 in fibrous plaques, whereas 122±21.64 and 152±23.35 in vulnerable plaques, respectively. No expression of BAX was found in controlled group. Conclusion The higher expression of Bax in vulnerable carotid plaque may be one mechanisms in molecular pathogenesis of carotid atherosclerosis which affect plaque stability and be the cause of higher incidence of stroke than fibrous carotid plaques, the regulation of BAX expression in different stage of atherosclerosis may provide targets in gene therapy for carotid atherosclerosis.  相似文献   
32.
THEβ2-adrenergicreceptor(β2-AR)ishighlyexpre-ssedonairwaysmoothmusclecellsinlung,anddefectsinβ2-ARsignalpathwaywereinvolvedinthepathogenesisofasthma.1 Humanβ2-ARgeneisanintr-onlessgenewithacodingblockconsistingof1239nucleo-tidesonchromosome5q31-32,genome-widesearchforas-thmasusceptibilitylocishowedthatmarkersonthisregionhavebeenlinkedtoasthma-associatedphenotypesinvariousethnicpopulations.2 Reihsausetal3 firstdescribedninecod-ingregionpolymorphisms,particularly,thethreecommonaminoacidsu…  相似文献   
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34.
腹腔镜与开腹胆囊切除胃肠压力变化的临床研究   总被引:5,自引:2,他引:3  
目的 :从胃肠道压力变化的角度探讨腹腔镜与开腹胆囊切除对胃肠运动功能的影响。方法 :腹腔镜胆囊切除 30例 (男 6例 ,女 2 4例 ,4 7± 4岁 ) ,开腹胆囊切除 30例 (男 9例 ,女 2 1例 ,4 7± 7岁 ) ,分别于手术前 1d行胃电图描记 ,记录术后 3、2 4、4 8、72h胃电图及监测胃窦、十二指肠和空肠压力 (移行性运动复合波 ,MMCⅢ )。结果 :(1)手术前腹腔镜和开腹胆囊切除患者胃电频率差异无显著性 (P >0 .0 5 ) ;(2 )腹腔镜胆囊切除组术后 3、2 4h正常波所占百分比低于术前 ,但差异无显著性 (P >0 .0 5 ) ,术后 4 8h恢复正常 ;(3)开腹胆囊切除组术后起 3h正常波所占百分比明显低于术前 ,差异有显著性 (P <0 .0 1) ,术后 2 4、4 8h正常波的百分比与术前差异无显著性 ,术后 72h恢复正常 ;(4) 2组患者术后胃窦、十二指肠及空肠压力低于健康人群 (P<0 .0 5 ) ;(5 ) 2组胃窦部收缩压力及收缩曲线下面积术后第 1、2、3d较术后 3h明显升高 (P <0 .0 5 ) ,且随时间延长有逐渐增大的趋势 ,腹腔镜组术后 72h恢复正常 ,十二指肠及空肠术后 3d内无明显变化 ;(6 ) 2组间胃电频率 ,胃窦部、十二指肠及空肠压力变化差异无显著性 (P >0 .0 5 ) ,但显示有差别。结论 :腹腔镜与开腹胆囊切除术均可引起胃电频率及胃肠压力变化 ,开  相似文献   
35.
目的:探讨丽珠肠乐、参苓止泻汤治疗婴幼儿迁延性或慢性腹泻的疗效。方法:将62例患儿随机分为两组,均补液、维持水电解质及酸碱平衡。治疗组用丽珠肠乐、参苓止泻汤,对照组用蒙脱石。7d为1个疗程,观察两组疗效。结果:治疗组的显效率、有效率、总有效率明显优于对照组(P〈0.01)。结论:丽珠肠乐、参苓止泻汤合治婴幼儿迁延性或慢性腹泻疗效满意。  相似文献   
36.
Background: Erythrocytes are transfused to improve oxygen delivery and prevent or treat inadequate oxygenation of tissues. Acute isovolemic anemia subtly slows human data processing and degrades memory, increases heart rate, and decreases self-assessed energy level. Erythrocyte transfusion is efficacious in reversing these effects of acute anemia. We tested the hypothesis that increasing arterial oxygen pressure (Pao2) to 350 mmHg or greater would supply sufficient oxygen to be equivalent to augmenting hemoglobin concentration by 2-3 g/dl and thus reverse the effects of acute anemia.

Methods: Thirty-one healthy volunteers, aged 28 +/- 4 yr (mean +/- SD), were tested with verbal memory and standard, computerized neuropsychologic tests before and twice after acute isovolemic reduction of their hemoglobin concentration to 5.7 +/- 0.3 g/dl. Two sets of tests were performed in randomized order at the lower hemoglobin concentration: with the volunteer breathing room air or oxygen. The subject and those administering the tests and recording the results were unaware which gas was administered. As an additional control for duration of the experiment, 10 of these volunteers also completed the same tests on a separate day, without alteration of hemoglobin concentration, at times of the day similar to those on the experimental day. Heart rate, mean arterial blood pressure, and self-assessed sense of energy were recorded at the time of each test.

Results: Reaction time for digit-symbol substitution test increased, delayed memory was degraded, mean arterial pressure and energy level decreased, and heart rate increased at a hemoglobin concentration of 5.7 g/dl (all P < 0.05). Increasing Pao2 to 406 +/- 47 mmHg reversed the digit-symbol substitution test result and the delayed memory changes to values not different from those at the baseline hemoglobin concentration of 12.7 +/- 1.0 g/dl, and decreased heart rate (P < 0.05). However, mean arterial pressure and energy level changes were not altered with increased Pao2 during acute anemia.  相似文献   

37.
顽固性心力衰竭(心衰)是临床上的难题,是指经过各种治疗措施均无明显改善的心衰。我们应用缬沙坦治疗19例顽固性心衰患,取得了预期的效果,报道如下。[第一段]  相似文献   
38.
为了培养医学生解决实际问题的能力,训练学生树立创新的意识和严谨的科学作风以及团结协作的精神品德,本文提出了几条关于医学微生物实验课的设计原则,并且提出了几条医学微生物实验室的管理建议,以防止实验室微生物感染事件的发生。  相似文献   
39.
Background: Anesthetic preconditioning (APC) with sevoflurane reduces myocardial ischemia-reperfusion injury. The authors tested whether two brief exposures to sevoflurane would lead to a better preconditioning state than would a single longer exposure and whether dual exposure to a lower (L) concentration of sevoflurane would achieve an outcome similar to that associated with a single exposure to a higher (H) concentration.

Methods: Langendorff-prepared guinea pig hearts were exposed to 0.4 mm sevoflurane once for 15 min (H1-15; n = 8) or 0.4 mm (H2-5; n = 8) or 0.2 mm sevoflurane (L2-5; n = 8) twice for 5 min, with a 5-min washout period interspersed. Sevoflurane was then washed out for 20 min before 30 min of global no-flow ischemia and 120 min of reperfusion. Control hearts (n = 8) were not subjected to APC. Left ventricular pressure was measured isovolumetrically. Ventricular infarct size was determined by tetrazolium staining and cumulative planimetry. Values are expressed as mean +/- SD.

Results: The authors found a better functional return and a lesser percentage of infarction on reperfusion in H2-5 (28 +/- 9%) than in H1-15 (36 +/- 8%; P < 0.05), L2-5 (43 +/- 6%; P < 0.05), or control hearts (52 +/- 7%; P < 0.05).  相似文献   

40.
1 Introduction Exposure to hostile stressors causes a series of coor- dinated responses in the body, such as alterations of neu- roendocrine secretion, immune reaction and behavioral manifestation to maintain homeostasis stability and sur-vival of the organisms. Stressors are divided into two main categories: physical, or systemic, and psychological, or emotional / processive. Each stressor might activate a spe- cific central pathway to induce a special neuroendocrine response, even cause stre…  相似文献   
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