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941.
Strokes may mimic or mask electrocardiographic abnormalities. An example of the little known masking phenomenon is described.  相似文献   
942.
The goal of this study was to consolidate information on genetic risk factors for gastric cancer. An additional aim was to investigate the influence of race on these genetic risk associations. Relevant studies were identified from PubMed and references of retrieved articles. Meta-analysis techniques were used to summarise associations between genetic polymorphisms and gastric cancer. A total of 203 relevant studies were identified, assessing 225 polymorphisms across 95 genes. Subgroup analysis indicated that Chinese, Japanese and Korean data were consistent and could be pooled. However, 6 of 13 polymorphisms (ACE I/D, CCND1 870G > A, CDH1160C > A, IL1B511C > T, IL4590C > T, IL10592A > C) displayed conflicting effects between Asian and Caucasian populations, three of which (ACE I/D, CCND1 870G > A, IL1B511C > T) had significantly different odds ratios between the two racial groups. In total, 37 polymorphisms across 27 genes were found to be significantly associated with gastric cancer in Asians, and 12 polymorphisms across 11 genes in Caucasians. Consolidated panels of polymorphisms associated with gastric cancer risk were identified in Asians and Caucasians. The results caution against the assumption that genetic risk factors are consistent between races.  相似文献   
943.
采用HPLC测定睾酮乳膏中睾酮的含量,以甲醇-水(70:30)为流动相,波长240nm,在40-360μg/ml范围内线性关系良好r=0.9999,本法操作简便,回收率高。  相似文献   
944.
The aim of this study was to examine the serum levels of insulin and some adrenal steroid hormones in men chronically exposed to low doses of trichloroethylene (TCE). A total of 85 workers participated in this study. Each worker had urine collected and analyzed for trichloroacetic acids (UTCA) on the same day that a blood sample was taken for analyses of serum testosterone, sex hormone-binding globulin (SHBG), androstenedione, cortisol, aldosterone, and insulin. The mean concentration of environmental TCE was 29.6 ppm and the mean UTCA was 22.4 mg/g creatinine (range 0.8-136.4). TCE exposure did not cause any significant changes to the adrenal steroid hormone productions. The results showed that UTCA was significantly correlated to serum insulin levels. Insulin and SHBG responded in tandem, with the highest levels found in workers exposed to TCE for less than 2 years; levels of both parameters were significantly lowered in those exposed for more than 2 years. A triphasic response in insulin levels to TCE, which depended on the duration of exposure, was noted. Initial exposure caused an acute rise in insulin levels. This was followed by a fall to normal levels in those exposed 2-4 years and then a slight rise in those exposed for more than 6 years. The mechanism for this pattern of response to TCE exposure is yet unknown.  相似文献   
945.
抗癌抗生素C1027与单克隆抗体Fab片段偶联物的抗肝癌作用   总被引:7,自引:0,他引:7  
抗人肝癌单克隆抗体(单抗)3A5用木瓜蛋白酶消化得到Fab片段。单抗3A5和Fab片段分别与抗癌抗生素C1027偶联,偶联物经克隆生成法测定对肝癌细胞有很强的杀伤作用,C1027,Fab-C1027和3;3A5-C1027的IC50分别为6.5×10-16,8.6×10-16和4.2×10-14mol·L-1;Fab-C1027偶联物对非靶细胞(KB)的IC50值为1.4×10-13mol·L-1,与靶细胞(BEL-7402)的IC50值相比,两者相差160倍。说明Fab-C1027的杀伤活性强于3A5-C1027,并对靶细胞呈选择性杀伤作用。给皮下移植人肝癌的裸鼠iv剂量0.1 mg·kg-1,结果C1027和Fab-C1027的抑瘤率分别为59和85%,说明Fab片段与C1027偶联物比游离C1027的疗效更高。  相似文献   
946.
Granular cell ameloblastomas are uncommon lesions accounting for about 3-5% of all histologic subtypes of ameloblastoma. The plexiform granular cell odontogenic tumour, on the other hand, is a newly described lesion characterised by a monophasic plexiform pattern of granular cells. This article reports a tumour found occurring in the left mandible of a 67-year-old Indian male which histologically showed features of both the aforementioned lesions.  相似文献   
947.
丝瓜叶中丝瓜皂甙O的化学结构研究   总被引:2,自引:0,他引:2  
梁龙  鲁灵恩  蔡元聪 《药学学报》1994,29(10):798-800
丝瓜叶中丝瓜皂甙O的化学结构研究梁龙,鲁灵恩,蔡元聪(四川省中药研究所重庆630065)丝瓜(LuffacylindricaRoem.)为常食蔬菜,其果实和藤叶中含有多种生理活性的化学物质。我们从丝瓜叶中分离出13个五环三萜类化合物,前文(1~3)已...  相似文献   
948.
949.
BACKGROUND: Sildenafil citrate (Viagra), a selective inhibitor of cGMP-specific phosphodiesterase type-5, has been used as an oral therapeutic drug for erectile dysfunction. The present paper is a clinical study of the success rate and side-effects of the use of sildenafil in a multi-racial population in Singapore. METHODS: From April 1999 to May 2000, 1520 patients were given sildenafil citrate. Of these, 912 patients (mean age, 54.6 years; age range, 22-99 years) were followed up and evaluated for clinical efficacy and safety of the drug. The mean duration of erectile dysfunction (ED) and follow-up periods were 31.5 and 3.0 months, respectively. RESULTS: Satisfactory erections assessed by single global efficacy question (GEQ) occurred in 83% of patients, major side-effects in the form of flushing (3.48%), headache (1.97%), blurred vision (1.25%), giddiness (1.18%), warmth (1.11%) and others (4.92%) were recorded in 127 patients (13.9%). Racially, Chinese men with ED had higher efficacy (85.7%), compared to Indian men (74.2%) and Malay men (72.8%). With respect to comorbid profiles, an efficacy of 77.8% (n = 271), 83.9% (n = 292), 86.4% (n = 44) and 83.3% (n = 199) was recorded in diabetic, hypertensive, ischemic heart disease patients and in benign prostatic hyperplasia patients, respectively. Patients who smoked (n = 135) and drank alcohol (n = 118) showed an efficacy of 80%. Baseline hormonal profiles of luteinizing hormone, follicle stimulating hormone, testosterone and prolactin did not affect the success rates of sildenafil citrate. Many patients had earlier received other forms of treatment (medicated urethral suppository for erection (MUSE; 84.9%); vacuum devices (86.8%), traditional medicines (100%) and other oral medications (89.2%)), but this did not influence the success rate of sildenafil citrate. But patients previously treated with prostaglandin-E intracavernosal injections were less successful on sildenafil citrate (77.3%). In the total cohort, 50 mg sildenafil citrate was an effective dose in 49% of patients and 46.5% patients needed 100 mg sildenafil citrate, while 4.1% of the total cohort needed only 25 mg sildenafil citrate. CONCLUSION: Oral sildenafil citrate has been shown to be an effective, safe and well tolerated drug in Singaporean men with ED, as in men from other parts of the world.  相似文献   
950.
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