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991.
Yao nationality is one of the minority nationalities living mainly in South China (Guangxi Province). The purpose of this
study was to provide data of MHC classI and GLO in Chinese Yao nationality and the different genetic background of Yao and Han nationality, the latter representing
the major nationality in China. The genetic polymorphism of MHC classI and GLO in Chinese Yao nationality was determined. Previously the Japanese were considered to have the lowest C*2C frequencies (0.9386), but now we ascertained that the Yao have the lowest C2*C frequencies (0.9336). The data concerning
gene frequencies of Yao are presented. They were also compared with the available data of Han. 相似文献
992.
Three representative types of houses in Beijing were selected and, in each type, smoking and nonsmoking households were compared, IP, RP, and CO concentrations in the living room and kitchen were monitored during each season, and the level of COHb in the heads of the households were measured. The study showed that indoor air pollution was rather severe, especially during winter, when particulate concentrations markedly exceeded the standard and CO concentration was as high as 47 ppm. Indoor air pollution was closely related to the type of house, particularly to the mode of heating. In houses, of the same type, pollution improved greatly after central heating facilities were installed. Analysis of 30 elements revealed that pollution was typically caused by coal burning, aggravated by dusty wind, but high indoor Pb levels were probably due to the use of LPG for cooking. In our study the effect of cigarette smoking was sometimes masked by the severe indoor pollution. 相似文献
993.
The hepatocarcinogen aflatoxin B1 is converted to reactive metabolites that bind covalently to cellular macromolecules. These metabolites may also react with glutathione, resulting in the formation of glutathione conjugates and detoxication of the reactive metabolite. When rats were pretreated with ethanol by gastric intubation at a dose of 100 mmol/kg, 6 hr (the time of maximal GSH depletion) before the administration of aflatoxin B1, the covalent binding of 8,9-epoxide-aflatoxin B1 to DNA in vivo was increased by 47% and the hepatotoxicity was also potentiated. However, the covalent binding was not increased by pretreatment with ethanol 18 hr (time with approximately normal GSH levels) before administration of the toxin, and no potentiation of hepatotoxicity was observed. Pretreatment with a non-toxic dose of ethanol had no effects on the activity of glutathione S-transferase and glutathione peroxidase. These results suggest that the depletion of GSH and the increased formation of DNA-adduct from the liver constitute an important mechanism for the potentiation of aflatoxin B1-induced hepatotoxicity by ethanol. 相似文献
994.
本文介绍正常人113名,肺部恶性病变49例及肺部良性病变33例的血清LSA测定结果,正常人血清LSA含量平均值为0.1243±0.0358g/L。特异性97.40%,男女间无差异,48例肺癌血清LSA平均值0.2698±0.0915g/L,敏感性85.40%;33例良性病变LSA平均值0.1712±0.0767g/L,特异性78.79%。肺癌患者血清LSA较良性病变明显升高,故测定血清LSA对鉴别良恶性病变有一定价值。 相似文献
995.
本文对52例涎腺恶性肿瘤进行了回顾性研究。52例中发生于腮腺者27例(51.9%);病理类型以腺样囊性癌和粘液表皮样癌最多见;随访2~8年,死亡19例,病死率最高者为腺癌(5/8)和鳞癌(3/5)。作者对腺样囊性癌的病理分型提出了不同看法。 相似文献
996.
997.
用免疫组织化学PAP法显示实验性脾虚组和正常对照组大鼠胰岛B细胞(胰岛素细胞)、A细胞(胰高血糖素细胞)和D细胞(生长抑素细胞).结果显示,实验组胰岛素分泌升高(P<0.01),胰高血糖素和生长抑素分泌下降(P<0.05)。实验结果提示大鼠胰岛A、B和D细胞分泌活动的变化与脾虚证的症候可能有密切关系。 相似文献
998.
An excess of blood loss and persistence of intraepithelial neoplasia after cervical conization occur with some frequency. Contact Nd:YAG laser conical excision of the uterine cervix is a new technique designed to remedy those problems. In this study, 36 women with histologically confirmed cervical intraepithelial neoplasia were treated with cylindrical excision of the uterine cervix with a contact Nd:YAG laser. The results were compared with those in 30 women who had similar lesions and were treated with the CO2 laser. Use of the Nd:YAG laser resulted in less intraoperative blood loss (mean +/- SD, 3.12 +/- 0.28 vs. 30.3 +/- 2.12 mL for the CO2 laser, P less than .01) and less postoperative blood loss. The volume of early bleeding was 6.23 +/- 1.21 vs. 20.13 +/- 2.24 mL for the CO2 laser (P less than .01), and that of late bleeding was 5.22 +/- 2.21 vs. 31.24 +/- 0.05 mL for the CO2 laser (P less than .01). The operative time was similarly less for the contact Nd:YAG laser (6.2 +/- 2.2 vs. 20.2 +/- 1.2 minutes for the CO2 laser, P less than .01). The dimensions of the excised specimens were similar. These findings suggest that the contact Nd:YAG laser offers distinct advantages over the CO2 laser in performing cylindrical excision of the cervix. 相似文献
999.
Monoclonal antibodies were raised against a specific human sperm protein and designated as the YWK-II mAb. The partial cDNA encoding the protein was isolated from a rat testis lambda gt11 expression library and the amino acid sequence of the protein was deduced. The cytoplasmic-transmembrane domains of the deduced protein had high homology with the A4 amyloid precursor protein of Alzheimer's disease. To evaluate the stage of spermatogenesis when the gene was expressed, single-stranded 35S-labeled RNA probes were prepared from the cDNA. By an in situ hybridization technique the mRNA for the antigen was detected in germ cells at all stages of spermatogenesis. The finding that the gene is expressed in spermatogonia suggests possible involvement in the initiation of germ cell differentiation or in the detachment of spermatogonia from the basement membrane. 相似文献
1000.
用短波紫外线照射患儿腰背部皮肤辅助治疗小儿肺炎,提示紫外线治疗组与对照组相比,显著缩短患儿发热。咳嗽及肺部湿罗音消失时间(P<0.01)。用化学发光法测定中性粒细胞吞噬功能,治疗组患儿血液内中性粗细胞吞噬功能显著提高(P<0.05)。同时测定治疗组患儿血中IL-2低于对照组(P<0.05),并对上述结果机理进行了探讨。 相似文献