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The molecular characterization of the mutations in hemophilia A patients is hampered by the large size of the factor VIII gene and the great heterogeneity of mutations. In this study, we have performed a protocol involving multiplex polymerase chain reaction in which 19 exons were amplified in four different combinations followed by nonradioactive single-strand conformational polymorphism (SSCP) to screen for mutations. Southern blotting was used to detect inversion of the factor VIII gene resulting from recombination between copies of the gene A (F8A) located in intron 22 of the factor VIII gene and two copies close telomeric region of X chromosome. Forty-two hemophilia A patients (21 with severe and 21 with mild-to-moderate disease) were studied. The inversion of factor VIII occurred in 13 of 21 patients affected by severe hemophilia A. One patient showed a large extra band in addition to the three bands observed after Southern blotting with the F8A probe. An abnormal electrophoretic pattern of SSCP was detected in 85% and 50% of the patients affected by mild-to-moderate and severe disease, respectively. Sixteen different mutations were identified. Eleven mutations were novel and comprised 9 point mutations and 2 small deletions. This study shows that the methodology used is safe and rapid and has potential for detecting almost all of the genetic defects of the studied hemophilia A patients.  相似文献   
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经肛门内镜显微手术切除直肠肿瘤   总被引:14,自引:3,他引:14  
目的评价经肛门内镜显微手术(TEM)切除直肠绒毛状腺瘤和早期直肠癌的应用效果。方法分析我院总结1995年11月至2001年12月27例TEM手术的临床资料。结果本组患者肿瘤直径中位值2.5cm,肿瘤下缘与齿状线距离(8.9±3.4)cm,肿瘤侵犯直肠周径范围(35.7±17.5)%。平均手术时间(109±46)min。平均住院日4.5d。无围手术期死亡。手术并发症有尿潴留、暂时性大便失禁和慢性阻塞性肺病(COPD)复发。术中2例切穿至腹腔,即刻内镜下修补成功。切缘100%瘤细胞阴性。病理示直肠绒毛状腺瘤14例、直肠腺癌13例,后者包括pTis2例,pT16例和pT25例。直肠癌腔内超声肿瘤T分期符合率为84.6%。5例pT2中2例中转前切除术,1例接受术后放疗,2例无附加任何治疗。平均随访18个月,所有病例无局部复发。死亡2例,但无复发迹象。结论TEM易行且安全,是直肠绒毛状腺瘤和部分T1直肠癌的治愈性手术,也可作为T2直肠癌的姑息性治疗手段。  相似文献   
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Osseous haemophilic pseudotumours are uncommon. The commonest sites of involvement are the femur and the pelvis. Trauma is the initiating factor in most reported cases and repeated bleeding into the lesion contributes to their growth. Most lesions grow slowly and are often asymptomatic. Complications include massive haemorrhage, infection and pathological fracture. We present an extremely unusual presentation where a large haemophilic pseudotumour of the pelvis extended to impinge the adjacent colon, resulting in large bowel obstruction.  相似文献   
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Objective : To evaluate the efficacy of biliary‐enteric bypass in the palliation of malignant hilar biliary obstruction. Materials and Methods : Records of 19 patients from 1995 to 1998 were reviewed. There were 13 patients with cholangiocarcinoma and 6 patients with carcinoma of the gallbladder. Single biliary‐enteric bypass had been performed in 13 of the patients; the rest had more than one biliary‐enteric anastomosis. Results : The 30‐day mortality was 21% (4/19 patients). Bile leakage occurred in 2 patients, leading, in both, to fatality. Excluding the 30‐day mortality, the median survival of patients with carcinoma of the gallbladder and cholangiocarcinoma was 116 days (43–200) and 202 days (47–1207), respectively. The mean hospital stay was 31 days (13–59) and all patients were discharged with their symptoms relieved and a drop in bilirubin of at least two‐thirds their pre‐operative level. The late complication rate was 26.7% (4/15 patients). Conclusion : Biliary‐enteric bypass is effective in the palliation of symptoms of patients suffering from unresectable hilar biliary obstruction, although it carries considerable mortality and morbidity. Stenting, rather than surgery, should be considered for patients with unresectable gallbladder cancer.   相似文献   
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OBJECTIVE: To review data on the long-term effects of prenatal exposure to the diabetic intrauterine environment in the Pima Indians of Arizona. This population has high rates of Type 2 diabetes mellitus that has a strong genetic component and develops at young ages. METHODS: Since 1965, Pima Indians at least 5 years old participated in a study of diabetes and its complications. This study consisted of biennial examinations with measurements of obesity and glucose tolerance and of glucose tolerance testing during pregnancy. The longitudinal nature of the study has permitted comparisons of data collected on children and young adults whose mothers were tested during pregnancy. RESULTS: Offspring of women who had diabetes during pregnancy were more obese and had a higher prevalence of Type 2 diabetes. Exposure to the diabetic intrauterine environment was responsible for about 40% of Type 2 diabetes in 5-19-year-old children between 1987 and 1996--approximately twice the attributable risk found between 1967 and 1976. Over 70% of persons with prenatal exposure have Type 2 diabetes at 25-34 years of age. CONCLUSIONS: The effects of the diabetic pregnancy can be thought of as a vicious cycle, with consequences for the offspring extending well beyond the neonatal period. The young woman whose mother had diabetes during pregnancy is at risk of perpetuating the cycle by developing diabetes by her childbearing years. In this population, much of the increase in childhood Type 2 diabetes can be attributed to the diabetic intrauterine environment, which may be a factor in the alarming rise of this disease nationally.  相似文献   
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The metabolic characteristics of type 2 diabetes, insulin resistance, and diminished insulin secretion are costly to measure directly. To evaluate the utility of several simple indices derived from insulin and glucose measurements, the indices were examined from 1982 to 1997 with respect to correlation with more sophisticated measures of insulin sensitivity and secretion in Pima Indians in the Gila River Indian Community of Arizona. Ability to predict the incidence of diabetes in 1,731 persons was also examined. Indices were calculated from fasting and 2-hour glucose (G0, G120) and insulin (I0, I120) concentrations obtained during an oral glucose tolerance test. Fasting serum insulin concentration and the insulin sensitivity index (10(4)/(I0 x G0)) each showed a moderate correlation with the estimate of insulin sensitivity derived from the hyperinsulinemic-euglycemic clamp (absolute value r approximately 0.60). They also strongly predicted the incidence of diabetes (incidence rate ratio comparing the most and least insulin-resistant tertile groups approximately 3.0). Corrected insulin response (I120/(G120 x (G120 - 70))) was modestly correlated with insulin secretion as measured by an intravenous glucose tolerance test (r = 0.35). Impaired insulin secretion assessed by this index predicted incidence of diabetes, particularly after control for insulin sensitivity index (incidence rate ratio = 1.6). Thus, simple indices of insulin sensitivity and secretion may be reasonable surrogates for more sophisticated measures in epidemiologic studies.  相似文献   
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