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151.
The significance of the demonstration of a clonal B-cell population in gastric lymphoid infiltrates was investigated by analysis of immunoglobulin heavy chain (IgH) gene rearrangements using sensitive polymerase chain reactions, employing fluorescently labelled primers to target the FR3 and FR1 regions. Tissue blocks were studied showing different histological features (high-grade lymphoma, low-grade lymphoma, and chronic gastritis) from 12 gastrectomies for primary gastric lymphoma, together with blocks showing chronic gastritis from 13 cases of gastric adenocarcinoma and biopsies from 33 patients with active Helicobacter -associated chronic gastritis. Clonal IgH gene rearrangements were detected in lymphoma samples from eight of the gastrectomies for lymphoma (67 per cent). In four of these eight specimens, clonal rearrangements were also detectable in the samples showing only chronic gastritis. Three of 28 (11 per cent) informative biopsies showing active Helicobacter -associated chronic gastritis had detectable clonal populations. Clonal rearrangements were also demonstrated in two of eight (25 per cent) informative blocks showing chronic gastritis from eight gastrectomies for adenocarcinoma. It is concluded that the detection of a clonal population in a suspicious lymphoid infiltrate does not confirm the diagnosis of lymphoma, nor does the absence of such a population imply benignity.  相似文献   
152.
Human muscle samples were obtained with the percutaneous biopsy technique. The samples were membrane-hyperpermeabilized (skinned) using a chemical or freeze-drying technique. Short single fibre segments were dissected from the sample, transferred to an experimental chamber, connected to a force transducer and manipulator, and exposed to temperature-controlled solutions. The force generating-capacity, the sensitivity of the contractile apparatus to calcium and the caffeine threshold for calcium release from the sarcoplasmic reticulum could be studied in the short muscle fibre segments obtained from man with the percutaneous muscle biopsy technique. The average length of the fibre segments between the connectors was 0.44±0.21 mm. Thus, detailed studies of the contractile machinery can be made on human skinned muscle fibres with only minimal discomfort to the patient or subject during biopsy, which should be useful in studies of neuromuscular disease, muscle plasticity or in applied physiology.  相似文献   
153.
总结卢尚岭教授对慢性心衰病机认识与治疗经验。心衰是各种心病日久的常见转归,其危害严重。由于导致心衰的疾病不同,因而患者发病年龄、体质、病程与病性有明显差异。心气心阳虚损,乃至衰竭,推动无力,气化失司,以致血瘀水停,是心衰发病的共同病机。五脏俱病,病位在心;心脏受邪,体用俱损。正虚邪实互为影响,心气心阳不足,正虚不充,必然导致气滞、痰浊、瘀血、寒凝、浊滞、水停等邪气内生,邪甚伤正。因此,治疗心衰强调补虚扶正与祛邪泄浊兼顾,以益气温阳、活血通脉、行水泄浊为治疗原则。创制心衰1号方、心衰2号方、益心汤等,并随证加减,常获满意疗效。  相似文献   
154.
目的:探讨温血诱导心停搏加冷血停搏液持续灌注对婴幼儿心脏手术的心肌保护作用。方法:选择体外循环心内直视手术的婴幼儿20例,随机分为两组:冷血停跳液间断灌注组;温血诱导心停搏加冷血停搏液持续灌注组(观察组)。检测于手术前后白细胞β2整合素(CD11b)表达,TNF-α和心肌钙蛋白I(cTnT)含量。观察自动复跳率(例),后并行时间,术后心功能,术后正性肌力药物用量。结果:两组相比,对照组CD11b表达增强(P<0.01),TNF-α和cTnI含量增高(P<0.01)。对照组后并行时间,术后正性肌力药物用量显著高于观察组(P<0.05);自动复跳率(例),心功能指标明显低于观察组(P<0.05)。结论:温血诱导心停搏加冷血停搏液持续灌注技术对婴幼儿心脏手术比冷血停搏液间断灌注有更好的心肌保护效果。  相似文献   
155.
微生物在水体重金属污染治理中的应用   总被引:6,自引:0,他引:6  
介绍重金属废水微生物处理技术的一般原理、研究现状及应用前景,指出了微生物处理技术的特点和优越性。  相似文献   
156.
We examined respiratory disease short-term disability claims submitted to the Mexican Social Security Institute during 2020. A total of 1,631,587 claims were submitted by 19.1 million insured workers. Cumulative incidence (8.5%) was 3.6 times higher than that for January 2015‒December-2019. Workers in healthcare, social assistance, self-service, and retail stores were disproportionately affected.  相似文献   
157.
158.
目的:探讨荷包牡丹碱(BiC)对海马CA2区的神经毒性作用以及电压依赖性钙通道(VDCC)对神经毒性作用的影响。方法:BiC6μmol·L^-1刺激培养的大鼠海马组织72h,同时用N,L以及P/Q型钙通道拮抗剂分别阻断相应的钙通道,测定神经细胞摄取的碘化丙啶(PI)。结果:BiC刺激6h后,神经细胞的PI摄取首先出现在CA2区。随着BiC刺激时间的延长,摄取PI的神经细胞的分布范围由CA2区扩散到其他区域。P/Q型VDCC拮抗剂抑制神经细胞的PI摄取,然而N和L型VDCC的拮抗剂无明显抑制效果。结论:在大鼠海马的组织培养中CA2区的神经细胞对BiC的刺激最易受损。CA2区神经细胞的损伤过程中P/Q型VDCC起重要作用。  相似文献   
159.
160.
FAK regulates cardiomyocyte survival following ischemia/reperfusion   总被引:1,自引:0,他引:1  
Myocyte apoptosis is central to myocardial dysfunction following ischemia/reperfusion (I/R) and during the transition from hypertrophy to heart failure. Focal adhesion kinase (FAK), a non-receptor tyrosine kinase regulates adhesion-dependent survival signals and unopposed FAK activation has been linked to tumor development. We previously showed that conditional myocyte-specific deletion of FAK (MFKO) in the adult heart did not affect basal cardiomyocyte survival or cardiac function but led to dilated cardiomyopathy and heart failure following pressure overload. In the present study, we sought to determine if FAK functions to limit stress-induced cardiomyocyte apoptosis. We reasoned that (I/R), which stimulates robust apoptotic cell death, might uncover an important cardioprotective function for FAK. We found that depletion of FAK markedly exacerbates hypoxia/re-oxygenation-induced cardiomyocyte cell death in vitro. Moreover, deletion of FAK in the adult myocardium resulted in significant increases in I/R-induced infarct size and cardiomyocyte apoptosis with a concomitant reduction in left ventricular function. Finally, our results suggest that NF-κB signaling may play a key role in modulating FAK-dependent cardioprotection, since FAK inactivation blunted activation of the NF-κB survival signaling pathway and reduced levels of the NF-κB target genes, Bcl2 and Bcl-xl. Since the toggling between pro-survival and pro-apoptotic signals remains central to preventing irreversible damage to the heart, we conclude that targeted FAK activation may be beneficial for protecting stress-dependent cardiac remodeling.  相似文献   
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