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991.
目的:探讨大负荷体能训练对大学生篮球运动员细胞免疫功能的影响。方法:14名男子大学生篮球运动员进行为期16周的集训,在训练期间分次对运动员外周血淋巴细胞亚群(CD3+、CD4+/CD8+淋巴细胞比值、NK细胞比例)和Th1/Th2细胞因子 mRNA表达进行检测。结果:在两次分别持续了6周的训练期后,运动员外周血CD3+淋巴细胞数于增加后出现显著下降,从第7周的峰值(59.74±7.18)下降至第16周的最低值(52.02±7.92)(P<0.001);CD8+细胞数第16周(31.15±6.25)与第3周(37.98±7.05)相比显著下降(P<0.05);NK细胞数从第7周的最高值(19.62±5.21)下降至第14周的最低值(14.41±7.93)(P<0.05);IL-4 mRNA表达训练后与基础值(6.56±0.71)相比显著增加,从第7周的7.04±0.35和第14周的7.30±0.25,直至第16周达到最大值7.36±0.45(P<0.05),其他指标的变化不具有统计学意义。结果提示,大负荷训练使运动员细胞免疫功能削弱,Th1/Th2平衡向Th2方向漂移。  相似文献   
992.
993.
目的探讨胆汁返流与幽门区局部神经递质一氧化氮的变化对应激性溃疡发病的影响及可能的机理。方法采用冷束缚应激方法复制应激性溃疡的动物模型,将60只成年SD大鼠分为两部分,第1部分:对照组10只,溃疡组30只,用于观测影响应激性溃疡发生的相关因素;第2部分:左旋硝基精氨酸甲酯(L—NAME)预处理组10只(L—NAME组),生理盐水预处理组10只(生理盐水组),用于观测幽门区局部一氧化氮含量变化对其他因素的影响。分别检测各组胃内胆汁酸浓度、胃黏膜溃疡指数(Guth评分)以及胃内pH值,用生化试剂盒检测幽门区一氧化氮的含量。结果溃疡组应激结束后1h幽门区一氧化氮含量达到峰值(P〈0.01),应激结束后2h胃内胆汁酸浓度和pH值均达到峰值(P〈0.01),应激结束后4h胃内溃疡指数达到峰值(P〈0.01)。L-NAME组的胃内胆汁酸浓度、溃疡指数及一氧化氮含量较生理盐水组显著降低(P〈0.01,P〈0.05),而胃内pH值的差异无统计学意义(P〉0.05)。幽门区一氧化氮含量与胆汁酸浓度呈正相关(r=0.715,F=12.55,P=0.017)。结论幽门区一氧化氮含量变化与胆汁的返流量之间存在正相关关系,而L—NAME的幽门区局部干预使幽门区一氧化氮含量减少,幽门松弛程度降低,胆汁返流量也随之减少,进而降低溃疡指数,起到保护胃黏膜的作用。  相似文献   
994.
Introduction Postoperative treatment for colorectal cancer depends on tumor stage as defined by the International Union Against Cancer (UICC). Adjuvant chemotherapy is not recommended in patients without lymph node involvement (UICC stages I and II). As many as 20–30% of these patients, however, will develop recurrence. Aims and objectives We conducted this study to determine the presence of disseminated tumor cells in the lymph nodes by quantitative real-time polymerase chain reaction (QRT-PCR) for cytokeratin 20 (CK20) in an attempt to provide supplementary information compared to histopathological findings. Materials and methods Using a standard QRT-PCR assay, we examined primary tumors and 391 lymph nodes from 31 patients with completely resected colorectal cancer. Results Of the 31 primary tumors, 29 were positive for CK20 by QRT-PCR. Discussion An examination of the lymph nodes from the 29 patients with CK20-positive primary tumors revealed that 35 (92.1% sensitivity) of the 38 histopathologically positive lymph nodes and 54 (16.7%) of the 324 histopathologically negative lymph nodes were positive by molecular analysis. CK20 expression was detected in 10 (100%) of 10 patients with a histopathologically positive lymph node status (pN1). In 9 (47.4%) of 19 patients with negative histopathological results (pN0), we detected a CK20 mRNA signal in at least one lymph node. Whereas eight patients with histopathologically negative lymph nodes could be upstaged on the basis of the molecular findings, no patient would be downstaged. Conclusion Our results suggest that QRT-PCR for CK20 is a useful tool for the quantitative detection of micrometastases in the regional lymph nodes. We introduce a standardized procedure that integrates a molecular diagnostic technique in the clinical staging.  相似文献   
995.
Background and aims The aim of this study is to evaluate the predictive accuracy of different scoring systems on surgery for perforated peptic ulcer referred to an academic department of general surgery in a tertiary reference center. Patients and methods Seventy-five consecutive patients (Male/female ratio = 64:11; mean age, 44 years; range, 16–85) with perforated peptic ulcer disease were investigated. Disease severity scores and mortality predictions were calculated using the collected data during admission. Discrimination and calibration characteristics of each system, namely, the acute physiology and chronic health evaluation II and III, the simplified acute physiology score II, and the mortality probability models (MPM) II, were determined by using the area under receiver operating characteristics curve and the Hosmer–Lemeshow goodness-of-fit test, respectively. Results Among the 75 patients included, there were eight (10.6%) mortalities. All systems had a reliable power of discrimination and calibration. Among the systems tested, MPM II was the best performing as far as discrimination and calibration characteristics were considered. The parameters of MPM II system that were related to systemic perfusion of the patient were significantly positive in patients who died compared to those who survived. Conclusions MPM II that predicted mortality at admission is better than the other systems in predicting mortality. Results also indicate the importance of maintenance of systemic perfusion of the patient at the early phases of peptic ulcer perforation.  相似文献   
996.
997.
Non-selective inhibition of monoamine oxidase (MAO) enzymes (ie, isoforms A and B) in the brain are associated with clinically significant antidepressant effects. In the US, the selegiline transdermal system (STS; EMSAM) is the first antidepressant transdermal delivery system to receive Food and Drug Administration (FDA) approved labeling for the treatment of major depressive disorder (MDD). Currently, the use of orally administered MAO inhibitor antidepressants (eg, phenelzine, tranylcypromine) is limited by the risk of tyramine-provoked events (eg, acute hypertension and headache, also known as the “cheese reaction”) when combined with dietary tyramine. The selegiline transdermal system is the only MAOI available in the US for the treatment of MDD that does not require dietary restriction at the clinically effective dose of 6 mg/24 hours. Delivery of selegiline transdermally (EMSAM®) bypasses hepatic first pass metabolism, thereby avoiding significant inhibition of gastrointestinal and hepatic MAO-A activity (ie, reduced risk of tyramine-provoked events) while still providing sufficient levels of selegiline in the brain to produce an antidepressant effect. At dosages of 6–12 mg/24 hours, EMSAM has been shown to improve symptoms of depression, have good tolerability, and have high rates of medication adherence. However, at higher doses of EMSAM (ie, 9 mg/24 hours or more), dietary restriction of tyramine intake is recommended. The introduction of EMSAM overcomes many of the safety concerns affiliated with the conventional oral MAO inhibitors and EMSAM may be considered another strategy for the treatment of MDD, especially in patients who cannot tolerate oral antidepressants, are poorly adherent, who present with atypical depressive symptoms, or have failed other antidepressants.  相似文献   
998.
We report the findings of spinal magnetic resonance imaging (MRI) in 2 patients who had undergone intrathecal chemotherapy and presented with the subacute onset of ascending numbness and weakness. MRI revealed a symmetric hyperintensity at the posterior columns of the spinal cord from the lower cervical region down to the conus medullaris level on T2-weighted images, and no abnormal enhancement. The imaging findings are similar to those seen in subacute combined degeneration (SCD), but the serum vitamin B(12) levels were normal in these 2 cases.  相似文献   
999.
1000.
Straight back syndrome (SBS) is a thoracic deformity with absence of upper thoracic spine kyphosis and heart compression. The anatomic abnormity of SBS may raise the difficulty of introcardial operation and increase the complicated risk of intervention performance. Here we report a case of SBS with complicated transseptal puncture during intervention catheter ablation of atrial fibrillation.  相似文献   
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