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191.
本文分析了20例PNH患者红细胞膜总脂,Ch/PIM比及磷脂组分,并比较了10例PNH红细胞膜AChE在PBS系统和生理盐水中的酶活性。发现PNH红细胞膜脂缺失严重,比正常少22%,但Ch/PIM比值及各磷脂相对含量均无明显改变。在PBS中AChE活性接近正常红细胞,但在生理盐水中明显低于正常红细胞,仅为正常的40%。表明PNH红细胞对补体敏感而溶血可能是由于补体导致膜脂缺失,进而破坏了红细胞膜结构的完整性而引起的,这也是AChE活性在低pH环境中酶活性比正常红细胞低的原因。  相似文献   
192.
BACKGROUND: The Functional Assessment of Cancer Therapy-Lung (FACT-L) questionnaire, which consists of a core questionnaire (the General Measure of FACT [FACT-G]) and a 9-item Additional Concerns comprised of a 7-item Lung Cancer Subscale (LCS), was developed in an English-speaking culture. The validation of the Japanese FACT-G was reported previously, and this report describes the cross-cultural validation of the LCS. METHODS: The Japanese version of the LCS was developed through an iterative forward-backward translation sequence used throughout the FACT Multilingual Translation Project. In evaluating psychometric performance, its construct validity was investigated with Cronbach's alpha coefficient and factor analysis. Clinical validities of a known-groups comparison and longitudinal validity were also investigated. RESULTS: The FACT-L was administered twice to 180 patients with lung cancer within 2 weeks. The Japanese LCS had borderline values for Cronbachs alpha coefficients (0.62-0.67). Factor analysis indicated that the LCS had the three dimensions of respiratory symptoms, appetite plus body weight, and clear thinking. For clinical validity, a known-groups comparison showed that the LCS could differentiate patients according to truth disclosure, as Japanese doctors sometimes do not fully inform terminally ill patients. However, responsiveness was not proved when performance status was used as an anchor, probably owing to the short interval between the administration of the two measures. CONCLUSION: The Japanese version of the LCS asked questions about multiple symptoms of patients with lung cancer, as did the original English LCS. The longitudinal clinical validity of the Japanese version should be investigated in future clinical trials.  相似文献   
193.
The multitest CMI system, a disposable device that simultaneously applies seven standardized preloaded antigens and diluent control, is a major advance for measurement of delayed type hypersensitivity (DTH) in assessment of cell-mediated immunity (CMI). The system was tested in 84 healthy volunteers, 42 in each sex, aged 4-62 years, to determine normal values for incidence and size of DTH responses to each of seven antigens. Incidence of positive responses to individual antigens varied from 84.5% to 11%, more than half of volunteers were reactive to Tuberculin, Candida and Diphtheria, and a third to Tetanus, Streptococcus and Tricophyton. 95.3% of volunteers to one or more antigens, and about two thirds to three or more. To better assess CMI, a two-part score based on 48-hour readings was employed. The mean number of positive antigens ranged between 2.2 and 3.3, the mean sum of their millimeter induration ranged between 10.8 and 18.2, the average sum of diameters were 16.7 mm in males and 15.2 mm in females. There was no statistic significance to sex and age during scoring, although there was somewhat higher in males, young and mature age groups. In our series, Tuberculin reaction is the highest one in this seven antigens, about 4.76% of volunteers are anergy. A statistical zone (95% confidence limits) of reduced DTH scores (hypoergy) was identified, it reveals sum of diameters less than 9mm in males and 7mm in females, number of positive antigens are less than 2 in each sex.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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195.
多价精子抗原表位肽的设计与免疫效应研究   总被引:2,自引:2,他引:0  
目的 开发可供两性使用的多价合成嵌合肽疫苗。方法 选择小鼠精子/睾丸特异性抗原SP17、Cyritestin中特异性氨基酸序列与牛核糖核酸酶非限制性T细胞表位作为骨架,按一定连接方式设计、合成新抗原35肽,并与弗氏佐剂混悬后免疫雌性BALB/C小鼠。结果 在430A固相自动肽合成仪上成功地合成35肽,并经HPLC纯化、质谱鉴定证实其纯度达95%以上;免疫后小鼠血清特异性IgG抗体滴度最高达1:6000,阴道粘膜冲洗液中特异性IgA抗体滴度最高达1:300;小鼠脾脏淋巴细胞增殖率达50%左右,淋巴细胞分泌的INF-γ和IL-4分别为60、108μg/ml;实验组BALB/c雌鼠妊娠率平均降至60%,每胎产仔数平均降低58%-71%。结论 含有两种特异性精子抗原中特异性氨基酸序列的新抗原可激发小鼠产生较理想的特异性体液免疫和粘膜免疫,并使小鼠受孕率下降,为研制适宜于两性的多价抗生育疫苗提供了实验基础。  相似文献   
196.
胆汁胆固醇对胆囊收缩素受体表达的影响   总被引:2,自引:0,他引:2  
目的:探讨胆汁胆固醇对胆囊收缩素受体(CCK-R)表达的影响。方法 采用放射免疫分析法和受体放射配基结合法检测对照组、高胆固醇组、自然恢复组及治疗组豚鼠门静脉血CCK水平、胆囊CCK-R的最大结合容量(Bmax)和亲和力(Kd),同时观察空腹胆囊体积(FV)、胆囊胆汁量(FB)和餐后胆囊体积(RV)、胆囊胆汁量(RB)及胆囊收缩率(E%)、胆汁胆固醇浓度的变化。结果 与对照组比较,高胆固醇组豚鼠FV、FB增大(P<0.05),RV、RB也增大,胆囊收缩率下降(P<0.01),胆汁胆固醇浓度升高(P<0.05),门静脉血CCK水平及CCK-R的Kd无改变,而CCK-R的Bmax下降(P<0.01);治疗组上述各项指标正常。结论 胆汁中的高胆固醇通过下调胆囊CCK-R表达而导致胆囊收缩功能障碍,降低胆汁高胆固醇浓度可以促进胆囊动力功能的恢复。  相似文献   
197.
Dihydroxyphenylglycol (DHPG) is the main intraneuronal metabolite of the sympathetic neurotransmitter, norepinephrine (NE), and dihydroxyphenylalanine (DOPA) the immediate product of the rate-limiting step in catecholamine biosynthesis. Simultaneous measurements of regional rates of appearance (spillovers) of NE, DOPA, and DHPG in plasma have the potential to provide unique information about aspects of sympathoneural function but have not actually been measured in humans. In the present study, spillovers of DHPG, DOPA, and NE in the heart, head, leg, and lungs, were estimated from regional extraction fractions of infused [3H]-1-NE, DHPG, and [13C6]DOPA or unlabelled DOPA in humans during cardiac catheterization. There was little cardiac extraction of DHPG (7 +/- SEM 2%) or DOPA (8 +/- 4%) but substantial extraction of NE (69 +/- 4%). Values for cardiac spillover of DHPG and DOPA therefore were similar to values for the arteriovenous increment times plasma flow (arteriovenous production rate), whereas the cardiac spillover of NE averaged about 7-times the NE arteriovenous production rate. Cardiac DHPG spillover (28 +/- 3 ng/min) exceeded the spillovers of NE (9 +/- 2 ng/min) and DOPA (15 +/- 4 ng/min). In contrast, cranial DOPA spillover (159 ng/min) exceeded those of NE and DHPG by 8- and 2-fold and accounted for about 1/10 of the total spillover of DOPA into arterial plasma. In the femoral vascular bed, arteriovenous production rates of NE and DHPG were unrelated to femoral spillovers of NE and DHPG. Arterial and regional clearances of [13C6]DOPA were similar to those of unlabelled DOPA. The results suggest that (1) endogenous NE, DOPA, and DHPG all are released into the bloodstream by the heart, head, and limbs of humans; (2) DHPG and DOPA are not co-released with NE; (3) cardiac arteriovenous production rates of DOPA and DHPG can be used to indicate cardiac spillover of these catechols, whereas the cardiac NE arteriovenous production rate substantially underestimates cardiac NE spillover; and (4) estimates of limb spillover of NE and DHPG require concurrent measurements of the corresponding regional clearances.  相似文献   
198.
Three hours after iv administration of alloxan and 5,6-diamino-2,4-dihydroxy-pyrimidine to mice infected with chloroquine-sensitive (CS) and chloroquine-resistant (CR) strains of Plasmodium berghei, the 2 compounds showed remarkable antimalarial actions. Parasitemia in CS and CR infected mice were reduced by about 50%. Slight hemolysis was seen in mice treated with alloxan but not in mice treated with 5,6-diamino-2,4-dihydro-pyrimidine. Alloxan did not inhibit glutathione reductase activity and no alloxan-glutathione complex was produced. No relationship between the antimalarial effects of alloxan and hemolysis or GSH content were found. It is suggested that the antimalarial effects of the two agents may be due to the inhibition of dihydroorotic acid dehydrogenase.  相似文献   
199.
200.
按照中国药典1985年版蕲蛇为蝰科动物五步蛇除去内脏的干燥体。近年在河北省的药村商品中,发现有游蛇科动物滑鼠蛇混入其中,充当蕲蛇。作者应用解剖、组织切片的方法,研究了蕲蛇与滑鼠蛇在形态组织上的鉴别特征。它们的主要区别在于:鳞片、体表花纹、牙齿、鼻骨的形态;椎骨的形态与组织特征。据此可以鉴别蕲蛇与滑鼠蛇的真伪。  相似文献   
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