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651.
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BCL-6 protein is expressed in germinal-center B cells   总被引:38,自引:14,他引:24  
  相似文献   
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A linear attenuation coefficient for water (mu = .15 cm-1) at 140 keV has been used in the determination of left ventricular volumes (LVV) by attenuation-corrected equilibrium methods. This theoretical value ignores the effect of Compton scatter and thus may be too high for human LVV determinations. The effective attenuation coefficient, mu', of the human chest was determined in ten normal volunteers using a Tc-99m esophageal source imaged with a gamma camera. Values for mu' at 30 degrees LAO in end-expiration, quiet breathing, and end-inspiration were .125 +/- .006 cm-1, .125 +/- .005 cm-1, and .113 +/- .007 cm-1, respectively (95% confidence interval). Values of mu' at 45 degrees LAO were .122 +/- .006 cm-1, .119 +/- .007 cm-1, and .099 +/- .009 cm-1, respectively, for the same conditions. The measured value of mu' for the source in a water phantom was .127 +/- .001 cm-1. This suggests that a value of mu' of .125 cm-1 may be appropriate for use in determining LVV in patients.  相似文献   
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藏药独一味根化学成分的研究   总被引:16,自引:0,他引:16  
继前报从藏药独一味(Lamiophlomisrotatakudo)根的正丁醇提取物中分离得到两个甙类成分。经化学和光谱分析,两个化合物的结构分别鉴定为3-羟基-4-甲氧基苯乙基-O-[α-L-吡喃鼠李糖(1→3)]-O-[β-D-呋喃芹菜糖(1→6)]-4-O-阿魏酰基-β-D-吡喃葡萄糖甙(1)和3-甲氧基-4-羟基苯乙基-O-[α-L-吡喃鼠李糖(1→3)]-O-[β-D-呋喃芹菜糖(1→6)]-4-O-阿魏酰基-β-D-吡喃葡萄糖甙(2),后者为一新化合物,命名为独一味甙A(lamiophlomiosideA)。  相似文献   
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A study of complications associated with paraaortic irradiation was undertaken in patients with uterine cervical cancer who had not undergone prior lymphadenectomy. Between 1975 and 1984, 29 highly selected patients received paraaortic irradiation as part of their definitive treatment for cervical carcinoma. Paraaortic fields were irradiated to a total dose of 4,200-5,000 rad (42-50 Gy), in fractions of 150-180 rad (1.5-1.8 Gy). An anteroposterior-posteroanterior technique was generally used. All fields were treated every day. There were no instances of small-bowel obstruction or other major complications, surgical procedures, or deaths caused by paraaortic irradiation. Eleven patients (38%) have no evidence of recurrent disease 23-120 months after completion of therapy. Paraaortic irradiation was well tolerated in this patient group without prior staging lymphadenectomy. Thus, in selected patients and with appropriate techniques, paraaortic irradiation for cervical carcinoma may be used with relative safety.  相似文献   
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Five boys with familial cytomegalic adrenocortical hypoplasia have been followed up for an average of 19 years. Despite treatment with replacement corticosteroids, all 5 failed to show a spontaneous onset of puberty and, when assessed at ages 13 to 19 years, all had both sexual infantilism and skeletal immaturity. Hypogonadism was confirmed by low levels of plasma testosterone, and pituitary reserve of gonadotrophin was shown to be inadequate by testing with gonadotrophin-releasing hormone. Two boys, both with adequate testosterone output on human chorionic gonadotrophin stimulation, were given gonadotrophin therapy, whereas the other 3 were treated with parenterally administered testosterone. With treatment, all 5 patients showed advances in pubertal staging. Although the mechanism of the hypogonadotropism remains unclear, the association of hypogonadotrophic hypogonadism with familial cytomegalic adrenocortical hypoplasia appears to be a constant one and may be considered as a treatable inherited syndrome of pubertal failure.  相似文献   
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Comparative sequence analysis of a 30-bp segment in the quinolone resistance-determining region of campylobacters not only allows for the detection of base changes associated with resistance but also is a powerful tool for species identification based on silent mutations.  相似文献   
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