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61.
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目的 探讨妊高征孕妇血浆中硒浓度与红细胞内谷胱甘肽过氧化物酶的关系.方法 应用原子吸收法及细胞化学发光检测法测定49例妊高征孕妇(妊高征组)和34例正常孕妇(正常妊娠组)血浆中硒的水平及红细胞内谷胱甘肽过氧化物酶(GSH-PX)的浓度.结果 妊高征组血浆硒水平及红细胞内GSH-PX浓度明显低于正常妊娠组,而且孕妇血浆中硒水平与红细胞内GSH-PX浓度之间呈直线回归关系,即随着血浆硒水平的升高,红细胞内GSH-PX也升高.结论 孕妇血浆硒水平与红细胞内GSH-PX浓度与妊高征的发病有一定的关系. 相似文献
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肽图分析是验证rhIL-2的重要手段之一.rhIL-2具有133个氨基酸,在其一级结构的序列中有四个甲硫氨酸切点,可用化学裂解的方法将甲硫氨酸肽键打开,进行肽谱分析,以对其进行验证.为了有效地对甲硫氨酸进行裂解,我们用70%甲酸溶解CNBr~2,保持CNBr的高浓度小体积,使rhIL-2在1.5mlEppedorf管中,室温条件下有效地打开甲硫氨酸肽键.同时比较了CNBr浓度、裂解时间以及在不同浓度的梯度胶中作SDS-PAGE对实验结果的影响,确定了最佳的实验条件,获得了良好的实验结果.本文虽以rhIL-2为例,但对所有带甲硫氨酸的细胞因子均可用本方法进行肽图分析. 相似文献
65.
S. Lehrer F. Fodor R. G. Stock N. N. Stone C. Eng H. K. Song M. McGovern 《British journal of cancer》1998,78(6):771-773
Epidemiological studies have demonstrated a clustering of breast and prostate cancers in some families. Moreover, there is an increase in the number of cases of prostate cancer in families with inherited mutations of the breast cancer susceptibility gene BRCA1. We assessed the role of BRCA1 and BRCA2 in prostate cancer. We tested for the BRCA1 185delAG frameshift mutation, found in 0.9% of Ashkenazi Jews, and the BRCA2 6174delT mutation, found in 1% of Ashkenazi Jews, in Ashkenazi Jewish men with prostate cancer. We studied 60 Ashkenazi men with prostate cancer. A family history was obtained by interview or a self-report questionnaire. Histological confirmation of diagnosis was obtained for all subjects. Ethnic background was confirmed for all subjects by self-report or interview. Mutations of BRCA1 and BRCA2 were detected by amplification of lymphocyte DNA from peripheral blood according to standard polymerase chain reaction (PCR) and dot blot procedures. Patients'' ages ranged from 55 to 80 years (mean +/- s.d. 70 +/- 5.25). There were six men with a family history of prostate cancer; three of these had a father with prostate cancer. Five of the men had a family history of breast cancer, in a mother, a sister or an aunt. None of the men had a family history of both breast and prostate cancer. None of the 60 men carried the 185delAG BRCA1 or 6174delT BRCA2 mutations. Of 268 Ashkenazi Jewish women with sporadic breast cancer, tested in an unrelated study, 16 carried either the 185delAG mutation of BRCA1 or the 6174delT mutation of BRCA2. There was a significant difference in the incidence of the BRCA1 and BRCA2 mutations in the breast and prostate cancer cases (P = 0.05, two-tailed Fisher''s exact test). The contribution of germline BRCA1 and BRCA2 mutations to prostate cancer incidence is probably small and could be limited to specific subgroups. 相似文献
66.
The effects of N-ethylmaleimide (NEM), an alkylating reagent to protein sulfhydryl groups, on tetrodotoxin-sensitive (TTX-S) and tetrodotoxin-resistant (TTX-R) sodium channels in rat dorsal root ganglion (DRG) neurons were studied using the whole cell configuration of patch-clamp technique. When currents were evoked by step depolarizations to 0 mV from a holding potential of -80 mV NEM decreased the amplitude of TTX-S sodium current, but exerted little or no effect on that of TTX-R sodium current. The inhibitory effect of NEM on TTX-S sodium channel was mainly due to the shift of the steady-state inactivation curve in the hyperpolarizing direction. NEM did not affect the voltage-dependence of the activation of TTX-S sodium channel. The steady-state inactivation curve for TTX-R sodium channel was shifted by NEM in the hyperpolarizing direction as that for TTX-S sodium channel. NEM caused a change in the voltage-dependence of the activation of TTX-R sodium channel unlike TTX-S sodium channel. After NEM treatment, the amplitudes of TTX-R sodium currents at test voltages below -10 mV were increased, but those at more positive voltages were not affected. This was explained by the shift in the conductance-voltage curve for TTX-R sodium channels in the hyperpolarizing direction after NEM treatment. 相似文献
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目的探讨Vitapex糊剂和氢氧化钙糊剂用于儿童年轻恒牙根尖诱导成形术的治疗效果。方法对85例儿童,98颗牙根尖发育未完成,牙髓病变已波及根髓、牙髓已坏死或并发根尖周炎的年轻恒牙分为2组,分别用Vitapex糊剂和氢氧化钙糊剂进行根尖诱导成形术,观察其根尖发育情况。结果Vitapex糊剂组总有效率为91.84%。氢氧化钙组总有效率为77.55%。2者疗效在统计学比较存在显著性。结论Vitapex糊剂作为一种根尖诱导成形剂具有良好的治疗效果。值得在临床推广应用。 相似文献
70.
S H Song M J Oh T Kim J Y Hur H S Saw Y K Park 《International journal of gynaecology and obstetrics》2006,92(3):212-216
OBJECTIVE: To compare the perioperative outcomes of two cesarean section methods, the finger-assisted stretching technique (FAST), based on a modified Joel-Cohen method, with the traditional technique. METHODS: A retrospective review of the records of 416 women who underwent cesarean sections at Guro Hospital, Seoul, Korea, between May 1993 and December 2001 was performed. Of the 416 women, 283 underwent cesarean sections with FAST and 133 with the traditional technique. RESULTS: Operative time was significantly shorter with FAST (15.3 vs. 42.6 min, P<.05), and FAST was associated with lower blood loss (601 vs. 928 mL, P<.05) and shorter hospital stay (3.7 vs. 6.5 days, P<.05). There were no significant differences in wound infection, voiding difficulty, and postoperative adhesions between the two methods. CONCLUSION: These results suggest that FAST may be the better technique. 相似文献