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71.
摘要 目的:为探讨淋巴细胞及其亚群、NK细胞与儿童原发性免疫性血小板减少症(ITP)复发的关系,评估其预测价值,为临床评估患者预后提供理论支持。方法:回顾性分析2017年12月-2021年12月于新疆医科大学第一附属医院儿科中心初发首诊为原发性免疫性血小板减少症的165例患儿,根据是否复发分为复发组与无复发组,评估ITP复发的影响因素,利用ROC曲线评估淋巴细胞计数绝对值对儿童ITP复发的预测价值,运用Kaplan-Meier法绘制与淋巴细胞计数绝对值相关的儿童ITP无复发生存曲线。结果:共纳入165名ITP患儿,复发率24.8%。淋巴细胞计数绝对值对儿童ITP无复发的ROC曲线下面积为0.704,95%CI为0.613-0.795(P<0.05),最佳截断值为3.21×109/L。儿童ITP是否复发与年龄、淋巴细胞计数、出血评分、ESR有关,两组比较差异有统计学意义(P<0.05)。儿童ITP是否复发与CD3+CD19-细胞计数、CD3+CD4+细胞计数、CD3+CD8+细胞计数、CD4+/CD8+细胞比例、NK细胞计数有关,两组比较差异有统计学意义(P<0.05)。结论:淋巴细胞计数绝对值可作为评估儿童ITP复发的预测指标,儿童ITP复发与初始T淋巴细胞亚群、NK细胞计数具有一定相关性。  相似文献   
72.
摘要 目的:探讨自体输血与异体输血对创伤性颅脑损伤(TBI)开颅手术患者凝血功能、细胞免疫功能和神经损伤标志物的影响。方法:回顾性分析2019年4月~2022年5月期间在本院行开颅手术的120例TBI患者的临床资料。根据输血方式的不同将患者分为异体输血组(n=58,异体输血)和自体输血组(n=62,自体输血),观察两组临床指标、细胞免疫功能、凝血功能、神经损伤标志物和不良反应发生率情况。结果:两组患者手术出血量、输血量、输注含凝血成分血制品比例对比,差异无统计学意义(P>0.05)。自体输血组出院时CD3+、CD4+、CD4+/CD8+高于异体输血组,CD8+低于异体输血组(P<0.05)。两组出院时凝血酶原时间(PT)、凝血酶时间(TT)、纤维蛋白原(FIB)、活化部分凝血活酶时间(APTT)组间对比无统计学差异(P>0.05)。自体输血组出院时S100钙结合蛋白B(S100B)、神经胶质原纤维酸性蛋白(GFAP)、神经元特异性烯醇化酶(NSE)低于异体输血组(P<0.05)。两组不良反应发生率组间比较无差异(P>0.05)。结论:自体输血用于TBI开颅手术患者,对患者的凝血功能影响较小,同时还可改善机体细胞免疫功能,降低神经损伤标志物水平。  相似文献   
73.
摘要 目的:分析乳腺癌根治术患者术前焦虑的影响因素,并探讨术前焦虑对患者术后恢复、细胞免疫功能和生命质量的影响。方法:选择我院2020年3月~2021年12月期间收治的拟行乳腺癌根治术的120例患者作为研究对象,术前1 d采用焦虑自评量表(SAS)评估所有患者的焦虑状况,根据是否存在焦虑分为焦虑组和无焦虑组,乳腺癌根治术患者术前焦虑的影响因素采用多因素Logistic回归分析。对比焦虑组和无焦虑组的术后恢复、细胞免疫功能和生命质量情况。结果:120例乳腺癌根治术患者中,有31例患者无术前焦虑,89例患者存在焦虑症状,根据是否存在术前焦虑分为焦虑组(n=89)和无焦虑组(n=31)。乳腺癌根治术患者术前焦虑与年龄、文化程度、家庭人均月收入、付费方式、婚姻状况、家庭支持、既往有无全麻史、术前住院时长、定期体检有关(P<0.05)。多因素Logistic回归分析结果表明:年龄<60岁、文化程度为小学及其以下、家庭人均月收入<3000元、婚姻状况为未婚、无家庭支持、既往无全麻史、术前住院时长>1 d是乳腺癌根治术患者术前焦虑的危险因素(P<0.05)。焦虑组的术后首次肛门排气时间、首次下床活动时间、术后住院时间均长于无焦虑组(P<0.05)。两组术后1个月CD3+、CD4+、CD4+/CD8+水平升高,且无焦虑组高于焦虑组(P<0.05),两组术后1个月CD8+水平下降,且无焦虑组低于焦虑组(P<0.05)。两组术后1个月生理状况、情感状况、社会/家庭状况、功能状况、附加关注评分和总分下降,且无焦虑组低于焦虑组(P<0.05)。结论:乳腺癌根治术患者术前焦虑发生率较高,其发生受到年龄、文化程度、家庭人均月收入、婚姻状况、家庭支持、既往有无全麻史、术前住院时长等多种因素的影响,可导致患者术后恢复时间延长,细胞免疫功能和生命质量降低。  相似文献   
74.
Healthy subjects were asked to make a voluntary ramp and hold contraction. The duration of the ramp stage was 500 ms, and the torque increment in this period was set to 15 Nm. The contraction was made from a relaxed and from a 5 Nm background torque situation. Hoffmann (H-) reflexes were elicited during the voluntary contraction, mostly with 100 ms intervals. These experiments showed an increase (facilitation) in the H-reflex before the torque or the EMG started to increase. This facilitation of the H-reflex remained during all the stages of the voluntary movement and declined to normal levels again only at the very end of the hold phase, which lasted for one second. This specific pattern of facilitation during a voluntary contraction was modeled using a modeling language, that is specifically designed to calculate neuronal systems with a high degree of reality (Ekeberg et al., 1991). Our model consisted of a motoneuron pool with 200 neurons connected to an EMG-model of the human soleus muscle and an extra group of higher-level neurons for controlling the amount of decrease of presynaptic inhibition. The model was used to simulate the observed modulation of the H-reflex with both a presynaptic and a postsynaptic mechanism. Simulations showed that a continuous change in the descending control signals is needed to make the model based on postsynaptic mechanism fit with the experimental data, whereas no extra control from the CNS over the excitatory drive to the motoneuron pool is needed when the decrease of presynaptic inhibition mechanism is applied.  相似文献   
75.
Abstract: GABAA receptors were characterized in cellular fractions isolated from adult bovine brain. The fraction enriched in cortical astrocytes is very rich in high-affinity binding sites for [3H]flunitrazepam and other "central-type" benzodiazepine ligands. The amount of specific [3H]flunitrazepam binding was more than five times higher in the glial fraction than in synaptosomal and perikaryal fractions. [3H]Flunitrazepam was displaced by low concentrations of clonazepam and other specific ligands for central GABAA receptors. Specific binding sites for GABA, flunitrazepam, barbiturates, and picrotoxin-like convulsants were characterized. Allosteric interactions between the different sites were typical of central-type GABAA receptors. The presence of α-subunit(s), as revealed by [3H]flunitrazepam photoaffinity labeling, was demonstrated in all brain fractions at molecular mass 51–53 kDa. Photoaffinity labeling was highest in the glial fraction. However, in primary cultured astrocytes from neonate rat cortex, no photoaffinity labeling was detected. Information obtained from astrocytes in culture should thus be taken with caution when extrapolated to differentiated astroglial cells. Our results actually show that, in mature brain, most of the fully pharmacologically active GABAA receptors are extrasynaptic and expressed in astroglia.  相似文献   
76.
Cysticercosis, a disease of economic and public health importance, is caused by Cysticercus cellulosae, the metacestode stage of Taenia solium. Experimental induction of cysticercosis was achieved in young pigs by feeding an optimum dose of 20,000 T. solium (Indian strain) eggs after immunosuppression, to assess the effect of albendazole and development of the immune response to cysticercus antigens before and after treatment.

Histopathological studies revealed the presence of cysticerci in liver, lungs and muscles. Treatment with albendazole at 15 mg kg−1 body weight daily for 30 days starting from day 0 or 15 days post-infection resulted in 100% cure rates. Increases in antibody titre to crude soluble extract and a Sephadex G-200 purified antigenic fraction of Cysticercus cellulosae were found on days 25, 40 and 55 post-infection in untreated pigs and those in which treatment started on day 15 post-infection, whereas no increase in antibody response was observed in pigs in which treatment started on day 0.  相似文献   

77.
高必需氨基酸转基因马铃薯的研究   总被引:8,自引:0,他引:8  
80年代以来,马铃薯遗传转化系统日趋成熟,转基因工程植株已被广泛应用于基础科学研究[1]。作为食物蛋白和能量主要来源的马铃薯,提高其蛋白质含量及质量的遗传工程研究正受到人们的普遍关注[2]。Yang等[2]将旨在改善氨基酸平衡的CAT-HEAAE(氯酶素乙酰转移酶-高含量人体必需氨基酸)融合基因导入马铃薯,获得了Southernblot、Northernblot、Westernblot的证据,但尚缺少氨基酸分析的资料。玉米醇溶蛋白(zein)[3]是一个富含甲硫氨酸的贮存蛋白,它和人工合成的HE…  相似文献   
78.
Cultures of human tonsil lymphocytes were exposed in a Crawford cell to a 450-MHz field (peak envelope intensity 1.0 mW/cm2), sinusoidally amplitude modulated (depth 80%) at frequencies between 3 and 100 Hz for periods up to 60 min. The Crawford cell was housed in a temperature-controlled chamber (35 degrees C) and control cultures were placed in the same chamber. Activity of cAMP-dependent protein kinase relative to controls remained unaltered by fields modulated at 16 or 60 Hz with exposures of 15, 30, and 60 min. By contrast, total non-cAMP-dependent kinase activity fell to less than 50% of unexposed control levels after 15 and 30 min exposures, but, despite continuing field exposure, returned to control or preexposure levels by 45 and 60 min. A smaller reduction (20-25%) also occurred with 60-Hz modulation and was also restricted to exposure durations of 15 and 30 min. CW 450-MHz fields were without effect. Reduced enzyme activity occurred with 16-, 40-, and 60-Hz modulation frequencies, but not with 3-, 6-, 80-, or 100-Hz modulation. The specific identity of this kinase is unknown. This rapid but transient reduction in lymphocyte protein kinase activity restricted to modulation frequencies between 16 and 60 Hz and to less than 30 min exposure is consistent with "windowing" with respect to modulation frequency and exposure duration.  相似文献   
79.
In this paper, we examine allometric and sexual-selection explanations for interspecific differences in the amount of sexual dimorphism among 60 primate species. Based on evidence provided by statistical analyses, we reject Leutenegger and Cheverud’s [(1982). Int. J. Primatol.3:387-402] claim that body size alone is the major factor in the evolution of sexual dimorphism. The alternative proposed here is that sexual selection due to differences in the reproductive potential of males and females is the primary cause of sexual dimorphism. In addition, we propose that the overall size of a species determines whether the dimorphism will be expressed as size dimorphism,rather than in some other form.  相似文献   
80.
Synechococcus leopoliensis was cultivated in a light/dark regime of 12:12 h. After onset of the illumination (2 h), the specific activity of nitrite reductase, glutamine synthetase and isocitric dehydrogenase increased; that of glucose-6-phosphate dehydrogenase decreased and that of nitrate reductase and NAD- (NADP) glutamate dehydrogenase remained nearly unchanged.This stimulation of the enzymes in vivo was also observed in vitro. Also, when extracts from darkened cells were incubated with thioredoxin and dithioerythriol enzyme activities increased in the same amount as obtained in vivo. In addition, glucose-6-phosphate dehydrogenase and isocitric dehydrogenase were stimulated by Mn2+ and Mg2+ in the assay mixture. Glutamine synthetase activity was enhanced only by Mg2+ while Mn2+ was inhibitory.The results are discussed with respect to the regulation of nitrogen metabolism by light.Abbreviations GS glutamine synthetase - GOGAT glutamate-oxoglutarate-aminotransferase - TR thioredoxin - DTE dithioerythritol - LD change from light to dark  相似文献   
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