The effect of passive smoking on asthma symptoms,atopy,and airway hyperresponsiveness in schoolchildren

Passive smoking is a major cause of respiratory morbidity, and is associated with increased bronchial responsiveness in children. To evaluate the effect of smoking by a parent on asthma symptoms, atopy, and airway hyperresponsiveness (AHR), we conducted a cross-sectional survey of 503 schoolchildren that involved questionnaires, spirometry, allergy testing, and a bronchial challenge test. If the PC20 methacholine was less than 16 mg/mL, the subject was considered to have AHR. The prevalence of a parent who smoked was 68.7%. The prevalence of AHR was 45.0%. The sensitization rate to common inhalant allergens was 32.6%. Nasal symptoms such as rhinorrhea, sneezing, nasal itching, and nasal obstruction were present in 42.7%. Asthma symptoms such as cough and wheezing were present in 55.4%. The asthma symptoms were significantly more prevalent in children who had a parent who smoked than in those whose parents did not. The nasal symptoms, atopy, and AHR did not differ according to whether a parent smoked. In a multiple logistic regression model, the asthma symptoms and atopy were independently associated with AHR, when adjusted for confounding variables. Passive smoking contributed to asthma symptoms in schoolchildren and was not an independent risk factor of airway hyperresponsiveness in an epidemiological survey.     

Prognostic factors of the long-term survival after transjugular intrahepatic portosystemic shunt in the treatment of gastric and esophageal variceal bleeding

Transjugular intrahepatic portosystemic shunt (TIPSS) is a promising method of treatment for gastric or esophageal variceal bleeding. This study was performed to determine the prognostic factors contributing to the survival of patients after TIPSS for gastric or esophageal variceal bleeding. One hundred and fifty-five patients who underwent TIPSS between September 1991 and March 2001 were followed up by clinical examination, upper gastrointestinal endoscopy, and Duplex sonography. The mean portohepatic pressure gradient prior to TIPSS was 20.5+/-9.93 mmHg and dropped to 10.7+/-6.62 mmHg after TIPSS (p<0.001). The cumulative survival rate was 75.1% at 6 months, 66.6% at 1 yr, 58.4% at 2 yr, and 38.1% at 5 yr. Survival after TIPSS was inversely related to the Child-Pugh classification (p<0.05). The rebleeding rate was 18.3% at 6 months, 21.0% at 1 yr, 32.8% at 2 yr, and 53.1% at 5 yr. The causes of deaths were hepatic failure (53.5%), recurrent variceal bleeding (11.6%), pneumonia (4.6%), sepsis (3.5%), hepatic encephalopathy (2.3%), and unknown (17.4%). Multivariate analysis (Cox proportional hazard model) revealed that the Child-Pugh classification and age were statistically significant independent prognostic factors. In conclusion, TIPSS is an effective method of treatment for variceal bleeding in cases where other treatment modalities including endoscopic therapy are unsuccessful and the most important prognostic factors are preprocedural hepatic reserve (Child-Pugh class) and age.     

带有蛋白转导结构域的bcr/abl癌蛋白片段表达及其跨膜转运

0　引言　人类免疫缺陷病毒 (human immunodeficiencyvirus,HIV) - 1编码的反式激活蛋白 TAT具有独特的跨膜运转方式 ,而且有转导速度快 ,效率高的特点 ,被称为蛋白转导结构域 (protein transduction domain,PTD) [1 ,2 ] .本研究用PCR扩增了慢性粒细胞白血病慢粒 bcr/ abl融合蛋白的基因片段 ,在其 5′端融合 PTD结构域的编码区后在大肠杆菌中进行了表达 .表达产物经纯化后 ,加入培养的 HL 6 0细胞 ,表达的蛋白可直接进入细胞内 .这一结果为用外源蛋白负载(L oading)免疫细胞提供了新的途径 .1　材料和方法1.1　 DNA重组　人工合…     

小分割分次立体定向放射治疗脑转移瘤近期疗效观察

目的观察小分割分次立体定向放射治疗(fractionated stereotatic radiation therapy,FSRT)脑转移瘤的近期疗效.方法15例病人单纯全脑外照射(WBRT组),中间平面剂量20～40Gy/10～20次/2～4周.17例病人接受FSRT(FSRT组),每次分次剂量为2.5～3.0Gy.其中11病人行单纯FSRT,中心总剂量为30～60Gy/1 0～20次/2～4周;6例病人先行WBRT,然后行FSRT,中心总剂量为46～60Gy/5～6周.结果KSP评分增加10分以上者,WBRT组为5 3.3%,FSRT组为82.4%.(P＜0.05).WBRT组有效率(CR PR)为50.0%;FSRT组有效率(CR PR)为80.0%.中位生存率:WBRT组为3.5月,FSRT组为10.0月.结论FSRT能有效地控制脑转移瘤,减轻神经系统症状,提高生存质量,延长病人生存期,而没有增加副作用,值得临床推广应用.     

Comparative mouse skin tumorigenicity and induction of Ha-ras mutations by bay region diol epoxides of 5-methylchrysene and 5,6- dimethylchrysene

We compared the tumor-initiating activities toward mouse skin of two structurally related polycyclic aromatic hydrocarbon diol epoxides: racemic anti-1,2,3,4-tetrahydro-5,6-dimethylchrysene-1,2-diol-3,4- epoxide (5,6-diMeCDE) and racemic anti-1,2,3,4-tetrahydro-5- methylchrysene-1,2-diol-3,4-epoxide (5-MeCDE). Tumors induced by these diol epoxides were analysed for mutations in the Ha-ras gene. 5,6- diMeCDE is derived from the non-planar parent compound 5,6- dimethylchrysene, and reacts to approximately equal extents with dA and dG in DNA, whereas 5-MeCDE is derived from a nearly planar parent compound, 5-methylchrysene, and reacts mainly with dG in DNA. 5,6- diMeCDE, at initiating doses of 33, 100 or 400 nmol per mouse, induced 1.2, 2.2 and 6.2 skin tumors per mouse, respectively. It was significantly less tumorigenic than 5-MeCDE which induced 3.1, 7.5 and 9.1 skin tumors per mouse at the same doses. Tumors induced by 5,6- diMeCDE had a large number of CAA-->CTA mutations in codon 61 of the Ha- ras gene: 50, 55 and 75% of the tumors analysed had this mutation at the 33, 100 and 400 nmol doses. No mutations were found in codons 12 and 13 in the tumors induced by 5,6-diMeCDE. In contrast, CAA-->CTA mutations in codon 61 were rarely seen in tumors induced by 5-MeCDE. At the highest dose of 5-MeCDE, 20% of the tumors analysed had mutations at G of codons 12 and 13. The results of this comparative study support the hypothesis that mutations in the Ha-ras gene in mouse skin tumors induced by PAH diol epoxides occur as a result of their direct reaction with the gene. However, pathways other than the commonly observed Ha- ras codon 61 mutations are clearly important in mouse skin tumorigenesis by these diol epoxides.      

继续医学教育活动的有效性

继续医学教育的目的是通过向医生提供最新的医学知识和技能,使医生在其整个职业生涯中,一直保持较高的医疗水平.但目前还没有充足的证据能证明继续医学教育活动的有效性,以及在继续医学教育活动中哪些教育方法和技术能最有效地传播和记忆医学知识.为了全面、系统地评估继续医学教育活动的有效性,以及了解不同的教育手段对医生知识、态度、技能、临床表现和临床效果的作用.美国约翰·霍普金斯大学医学院、美国医疗保健研究与质量管理署和美国胸科医师学会的专家共同进行了一项系统回顾性研究.