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Comparative studies are made on the relative percentages of amino acid content and LDH isozyme by electrophoresis and Slab-PAGE in adult worms of Ascaris lumbricoides, Ascaris suum and Toxocara canis. The results show that there are remarkable differences of Arg and His of 17 amino acids bet. ween Toxocara canis and human intestinal ascaris, human biliary ascaris and pig ascaris; there are also obvious differences of band positions of LDH isozyme electrophoretic patterns and band position and amount of slab-PAGE patterns among them, whereas no marked differences are found in these three indices in human intestinal ascaris, human biliary ascaris and pig ascaris.  相似文献   
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In vitro activation of purified rat microsomal glutathione transferase 1 (MGST1) by S-nitrosylation has been recently reported. This study was designated to explore its in vivo relevance. Unexpectedly, we failed to detect S-nitrosylated MGST1 in rat liver microsomes treated with S-nitrosoglutathione (GSNO); neither did we observe MGST1 S-nitrosylation in endotoxin challenged rats. However, by using matrix-assisted laser dissociation/ionization time-of-flight mass spectrometry (MALDI-TOF MS), we identified several other proteins which are susceptible to S-nitrosylation in liver microsomes, including retinol dehydrogenase type I (RODH I), aldolase B, cytochrome P4502C11, and peroxiredoxin 1. Our results suggest that MGST1 S-nitrosylation is unlikely to be involved in the protection mechanism against nitrosative stress caused by endotoxin challenge. Further studies on the novel S-nitrosylable microsomal proteins are also warranted.  相似文献   
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高歌  何露 《中国卫生统计》2003,20(5):276-278
目的 对多分类有序反应变量logistic回归的应用条件寻求科学合理的检验方法。方法 使用卡方分布的理论,SAS软件及抽样调查方法。结果 设计出多分类有序反应变量logistic回归应用条件的卡方检验方法,推导出反应变量取各水平的概率计算公式及卡方检验中理论值、自由度的计算公式,并在作者主持的国家医师资格临床实践技能考试研究中取得了成功效果。结论 多分类有序反应变量logistic回归得到完善和补充,具有较大的理论和实际意义。  相似文献   
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Prevalence of vitamin B12 deficiency among geriatric outpatients.   总被引:3,自引:0,他引:3  
BACKGROUND. Healthy people can have low levels of cobalamin (vitamin B12) without symptoms or signs of cobalamin deficiency. Early detection of deficiency is imperative for treatment to be effective. Development of radioimmunoassay tests has greatly improved accurate determination of cobalamin (Cbl) levels. Nevertheless, results of studies of Cbl deficiency vary widely because of the variety of populations studied. METHODS. In a prospective study, we tested 100 consecutive, unselected geriatric outpatients in a primary care setting to determine the prevalence of cobalamin deficiency. All patients, 65 years of age or older, who visited the office of one of the authors during a period of 11 consecutive working days, had their serum Cbl level checked. If the level was 299 pg/mL or lower, serum intrinsic factor and parietal cell antibodies, serum gastrin, part 1 Schilling test, serum methylmalonic acid, and total homocysteine were done, when possible, for the diagnosis of type A gastritis and intracellular Cbl deficiency. RESULTS. Sixteen percent of geriatric outpatients had serum Cbl levels of 200 pg/mL or below, and 21% had levels between 201 and 299 pg/mL. Among the 16 patients with levels < or = 200 pg/mL, 2 patients had macrocytic anemia, 3 patients had peripheral neuropathy, and 8 patients had type A gastritis. Among the 21 patients with levels of 201 to 299 pg/mL, 2 patients had peripheral neuropathy, 9 patients had type A gastritis, and none of the patients had macrocytic anemia. Among the patients whose methylmalonic acid and total homocysteine levels were determined, the results were high in 80% of those with Cbl levels < or = 200 pg/mL and in 33% of those with levels from 201 to 299 pg/mL. CONCLUSIONS. The prevalence of Cbl deficiency in geriatric outpatients was found to be higher than in any recent report. The lower limit of the normal range for Cbl level should be increased to 300 pg/mL.  相似文献   
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We quantitatively investigated the effect of carbidopa/levodopa (25/100) on physical fatigue during finger tapping and force generation in a double-blind, placebo-controlled crossover study. Parkinson's disease (PD) subjects were randomly assigned to carbidopa/levodopa or placebo for Visit 1 or 2 and participated in the following two studies: (1) Finger tapping. Twenty-five PD patients used their index fingers to strike two keys 20 cm apart on a musical instrument digital interface (MIDI) keyboard. The slopes of the regression line of dwell time and movement time were used to assess the rate of fatigue development. (2) Force generation. Twelve PD patients contracted the wrist extensors maximally to obtain a baseline maximum voluntary contraction (BMVC) force. Then they repetitively contracted the wrist extensors at 50% of the BMVC for 7 seconds and rested for 3 seconds. An interval maximum voluntary contraction (IMVC) was measured every three repetitions. Fatigue was defined as an IMVC of less than 60% of the BMVC. The slope of the regression line of IMVC was used to assess the rate of force decline. These two studies were repeated 1 hour after carbidopa/levodopa (25/100) or placebo. Subjects filled out the Multidimensional Fatigue Inventory (MFI) at the beginning of the first visit. Results showed that the slope of dwell time decreased with levodopa but not with placebo (P = 0.004). The rate of force decline also decreased with levodopa but not with placebo (P = 0.01). The subscores in the dimension of physical fatigue in the MFI did not correlate with the rate changes in dwell time or the rate changes in force decline. We concluded that (1) levodopa improves physical fatigue in finger tapping and force generation, (2) physical fatigue in Parkinson's disease is at least partially related to dopamine deficiency, and (3) the MFI measures different aspects of physical fatigue compared with those measured by finger tapping and force generation.  相似文献   
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主动回避条件反应率>80%的老年大鼠为学习好组,<30%的为学习差组。学习好组在高频短串刺激后颗粒细胞层出现海马长时程突触增强(LTP)效应:颗粒细胞核内Ag-NOR面积/胞核面积比值平均为0.154±0.0043;单个胞核内Ag-NOR平均为3.051±0.2212个,学习差组高频短串刺激引起颗粒细胞层群峰电位长时程抑制;颗粒细胞核内Ag-NOR面积/胞核面积比值平均为0.077±0.0023;单个胞核内Ag-NOR平均为1.839±0.1421个,2组间3指标均有显著差异,表明年老大鼠学习能力与LTP效应有关,学习差的老年大鼠海马齿状回颗粒细胞rDNA的转录活性较学习好的明显降低。  相似文献   
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目的探讨胰腺黏液非囊性癌的组织学特点、生物学特征、治疗方法及预后。方法回顾性分析复旦大学附属中山医院普外科2000~2005年间收治的9例胰腺黏液非囊性癌病人的临床特点、影像学改变、病理学特征、治疗经过及随访资料。9例胰腺黏液非囊性癌病人,男7例,女2例,年龄平均(63·1±8·7)岁。肿瘤位于胰头8例,胰体尾1例。行胰十二指肠切除术8例,其中4例合并扩大淋巴结清扫术,1例行胰体尾切除。结果术后病理报告:瘤体平均4·3cm×4·3cm×4·4cm。镜下见8例胰头肿瘤均侵犯十二指肠,侵犯肠系膜上静脉4例。肿瘤侵犯神经3例,淋巴结转移2例。镜下肿瘤表现明确的间质黏液湖及其上漂浮较少的恶性上皮细胞。随访8例,死亡5例。术后存活5~23个月,平均存活11个月,均死于肿瘤复发和肝转移。结论胰腺黏液非囊性癌应是胰腺恶性肿瘤的一个独立的类型,其生物学特征有待进一步研究。  相似文献   
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