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11.
癌组织中p16基因甲基化分析   总被引:1,自引:0,他引:1  
目的探讨抑癌基因p16在胃癌组织中是否存在甲基化异常及其与胃癌发生发展的关系.方法对20例胃癌组织及相应正常胃粘膜组织应用甲基敏感酶(HpaII)和甲基非敏感酶(MspI)酶切,结合PCR扩增技术,对p16基因外显子1、外显子2的二核苷酸胞嘧啶特定序列5'-CCGG-3'位点甲基化进行检测.结果20例胃癌组织中,p16基因外显子1、2异常甲基化分别为5例(25%)和9例(45%),正常组织未发现甲基化异常;14例高甲基化标本中,中分化胃癌4例,低分化7例,高分化1例;有2例存在外显子1、2同时甲基化异常,二者均为低分化胃癌,进展期胃癌(Ⅲa、Ⅳ期各1例)中1例呈现泳动易位;外显子2甲基化异常多发生于晚期肿瘤患者(P<0.05).结论p16基因甲基化异常可能会造成基因功能丧失,从而失去对细胞增殖的负性调控作用,导致胃癌发生与进展;外显子2高甲基化与临床进展有关,可能为晚期事件.  相似文献   
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针对一般遗传算法在求解优化问题的多个优化解时的局限性,结合曲面投影与遗传算法的基本思想,提出了一种基于曲面投影的投影遗传算法用于解决此类问题,数值验证的结果表明了本算法的有效性和实用性。  相似文献   
14.
目的探讨胰腺癌的CT诊断价值.方法对76例胰腺癌的CT表现进行分析并与手术病理结果对照.结果①胰腺癌在CT上表现为低密度的肿块,不强化或强化不明显,肿块边缘不规则强化;②胰头癌可引起胆总管、胰管的扩张;③胰腺癌多伴邻近血管及脏器受侵.结论 CT能正确评价胰腺癌及胰周浸润,是判断胰腺癌能否手术切除的重要检查手段.  相似文献   
15.
Health care delivery in Mexico is divided in three groups: a social sector that covers approximately 53% of the population and is financed by the labor force, the state and the employer; a public, or open, sector that covers 33% of the population and is financed by federal and state funds; and a private sector that covers about 5% of the population and has two categories, the not-for-profit hospitals and the profit-oriented institutions. Most medical practitioners can work in any of the three groups or in several. Nine percent of Mexico's population, because of extreme ignorance, poverty, or isolation, have no or limited access to medical care. Mexico has 58 medical schools, which graduate about 7800 new physicians annually, awarding them the title Medico cirujano (Physician Surgeon). There are more than 160,000 physicians in Mexico, 20,000 of whom are unemployed. Each year, approximately 12,000 physicians compete for the 4306 places in the official residency training programs for all specialties. Of those taking the examination, 2000 try to get one of the 625 slots available for training in general surgery. Most of the surgical training programs in Mexico have a 3-year duration. The Mexican Academy of Surgery, the Mexican Society of General Surgery, and the Mexican Board of Surgery, as well as private individuals and organizations, are working to improve the quality of medical education and trying to establish a 5-year training program in surgery. The rapid movement toward modernization that is sweeping the country must include the improvement of surgical education as well.
Resumen La atención de la salud en México está dividida en tres grupos: el Sector Social que cubre approximadamente el 53% de la población y que está financiado por la fuerza laboral, el Estado y el empleador; un Sector Público o Abierto que cubre el 33% de la población y que es financiado con fondos federales y estatales; y un Sector Privado que cubre el 5% de la población y que posee dos categorías: la de los hospitales sin ánimo de lucro y la de las instituciones con ánimo de lucro. La mayoría de los médicos pueden trabajar en cualquiera de los 3 grupos, o en combinación. El 9% de la población mexicana, por extrema ignorancia, pobreza y aislamiento no posee acceso alguno, o sólo lo tiene mínimo, a la atención médica.México posee 58 facultades de medicina, las cuales gradúan alrededor de 7.800 nuevos médicos anualmente, a quienes se les expide el título de médico cirujano.Hay más de 160.000 médicos en México, 20.000 de los cuales se encuentran desempleados. Cada año aproximadamente 12.000 médicos compiten por las 4.306 plazas en los programas oficiales de adiestramiento en las diferentes especialidades. De aquellos que presentan examen, 2.000 tratan de obtener uno de los 625 lugares disponibles para adiestramiento en círugía general.La mayoría de los programas de adiestramiento quirúrgico en la nación son de tres años de duración. La Academia Mexicana de Cirugía, la Asociación Mexicana de Cirugía General y el Consejo Mexicano de Cirugía, así como individuos y organizaciones privadas, trabajan en pro del mejoramiento de la calidad de la educación médica y tratan de establecer un programa de adiestramiento en cirugía de cinco años de duración. Los rápidos cambios de modernización que ocurren en el país deben incluir también el mejoramiento de la educación quirúrgica.

Résumé L'administration des soins au Mexique est repartie entre trois secteurs: 1) Le secteur social qui couvre environ 53% de la population et qui est financé par la caisse des ouvriers, celle de l'état et celle du patronat; 2) un secteur public ou ouvert, qui couvre environ 33% de la population et qui est financé par des fonds fédéraux et gouvernementaux et enfin 3) un secteur privé, qui ne couvre que 5% environ de la population et qui comprend deux catégories, les hôpitaux à but non-lucratif et les institutions à but lucratif. La plupart des médecins peuvent exercer dans un ou plusieurs de ces trois groupes. Neuf pourcent de la population, en raison d'une extrême pauvreté, de son ignorance ou de son éloignement, a peu ou pas d'accés à des soins structurés.Il y a 58 écoles de Médecine au Mexique, produisant environ 7800 nouveaux médecins par an. Ils reçoivent le titre de Medico Cirujano littéralement, Médecin chirurgical. Il existe plus de 160000 médecins au Mexique, dont 20000 sont sans travail. Chaque année, environ 12000 médecins sont en compétition pour obtenir un des 4306 postes officiels de résidents, toutes spialités confondues. Parmi ceux qui se présentent, 2000 sont candidats pour un poste en chirurgie. La plupart des programmes d'enseignement durent trois ans. L'Académie de Chirurgie Mexicaine, La Société Mexicaine de chirurgie Générale et le comité d'accréditation chirurgicale, tout en accord avec les institutions privées et leur dirigeants oeuvrent pour un programme de cinq ans. La vague de progrès, ressentie dans tous les domaines, qui traverse actuellement le pays doit aussi intéresser l'amélioration de l'enseignement en chirurgie.
  相似文献   
16.
Tenidap is a novel anti-rheumatic drug that combines cytokinemodulation with cyclo-oxygenase inhibition. This 24-week, multicentre,double-blind, randomized study compared the clinical efficacy,biochemical effects and safety of tenidap 120 mg/day (once daily)with diclofenac 150 mg/day (50 mg t.i.d.) in the treatment of384 patients with active rheumatoid arthritis. After 24 weeks,improvement with tenidap was significantly greater than withdiclofenac for all five primary efficacy parameters, two ofthe four secondary efficacy parameters and 11 of the 13 ArthritisImpact Measurement Scales assessments. The superior efficacyof tenidap was apparent after 4 weeks of treatment with furtherimprovements observed by 24 weeks. The probability of discontinuationdue to lack of efficacy was significantly greater in the diclofenacgroup. Tenidap but not diclofenac was associated with significant,rapid and sustained reductions in C-reactive protein and serumamyloid A levels and with a significant reduction in plasmainterleukin-6. The nature and frequency of side-effects weresimilar in the two groups as was the discontinuation rate fortreatment-related safety reasons. Tenidap was associated withan equal incidence of elevated transaminases, but a higher incidenceof mild (  相似文献   
17.
Correlation of p53 gene/protein alterations with incidence of oncogene amplification, a potential marker of prognosis, was evaluated in 26 fresh breast cancer samples. p53 gene was analyzed by SSCP and DNA sequencing while p53 protein status was investigated by immunohistochemistry (IH). Amplification of c-erbB2/neu, c-myc, N-ras, int-2, hst, PRAD-1 and EGFR genes was studied by slot blot and in situ hybridizations. p53 alterations were found in 31% cases by SSCP and 42% by IH; gene amplification was detected in 27% cases. p53 gene alterations correlated significantly with gene amplification (p=0.006) and also with higher S-phase index (p=0.026), aneuploidy (p=0.026) and negative progesterone receptor status (p=0.043).  相似文献   
18.
OBJECTIVE: Recent studies have concluded that Native North American children have higher proportions of overweight and obesity than children from the general North American population. This study presents anthropometric data on a representative sample of children from the Mohawk Nation that can be used for comparison with other Native American populations. DESIGN: This is a cross-sectional study comparing distributions of anthropometric characteristics of Mohawk children to the corresponding age and gender data from the Second National Health and Nutrition Examination Survey (NHANES II). Weight, height, triceps and subscapular skinfold thickness, and waist and hip circumferences were measured in 527 children. SUBJECTS/SETTING: All children in grades 1 to 6 (aged 6 to 11 years) in the 3 elementary schools of 2 Mohawk communities in Canada, for whom parental consent was obtained, were enrolled in the present study. There were no exclusion criteria. With a participation rate of 83%, the 527 children enrolled in this study represent an unbiased sample of the population from 2 Mohawk territories. RESULTS: Compared with children studied in NHANES II, Mohawk children were similar in height and triceps skinfolds but were generally heavier, had thicker subscapular skinfolds, and had greater waist and hip circumferences. These differences were greater in older children. Mohawk children who had extreme-high weight values compared with their population means were heavier than their NHANES II counterparts. APPLICATIONS/CONCLUSIONS: Results indicated that, on average, Mohawk children seem to be slightly heavier than children in NHANES II. Except for those with extreme overweight values, Mohawk children show less variation of weight and body mass index than children in NHANES II. Finally, overweight Mohawk children seem to be more likely to carry their excess body fat truncally, compared with overweight children from NHANES II. Health practitioners working with Native American populations should be careful when assessing childhood obesity. Simple comparisons of weight or body mass index with NHANES standards may lead to inappropriate risk assessments.  相似文献   
19.
高效液相色谱法测定绿茶和饮料中的咖啡因   总被引:5,自引:0,他引:5  
采用反相高效液相色谱法,固定相为十八烷基硅烷键合硅胶,以乙腈-水(20:80)为流动相,检测波长274nm,测定绿茶和饮料中的咖啡因含量。结果线性范围为3.9~3900ng,r=O.9999;绿茶和2种饮料的平均加样回收率分别为100.2%、100.1%和99.8%。该方法准确、简便、快速,适合绿茶和可乐型饮料中咖啡因的测定。  相似文献   
20.
BACKGROUND: We conducted a phase I/II study of weekly irinotecan [30 min intravenous (i.v.) infusion] combined with 5-fluorouracil (5-FU 3 g/m(2) weekly 48 h i.v. infusion, TTD regimen) as first-line chemotherapy for patients with advanced colorectal cancer (CRC). PATIENTS AND METHODS: The maximum tolerated dose (MTD) and the dose-limiting toxicity (DLT) in the treatment of gastrointestinal solid tumors (in phase I), and the antitumor activity and toxicity of the recommended phase I dose (in phase II) were determined. RESULTS: Diarrhea was the DLT, and irinotecan 80 mg/m(2) plus 5-FU 3 g/m(2) was the recommended phase I dose. In phase II, the confirmed response rate was 44% [95% confidence interval (CI) 29% to 59%] and the median overall survival was 23.8 months. However, grade 3/4 diarrhea affected 59% of patients and led to withdrawal of three patients. A second cohort of patients studied using the same schedule but with a reduced 5-FU starting dose of 2.25 g/m(2) showed improved tolerance (the incidence of grade 4 diarrhea decreased from 28% to 11% and overall grade 3/4 diarrhea to 56%, with no patient withdrawals) but the confirmed response rate was 28% (95% CI 14% to 45%) and median overall survival was 17.2 months. CONCLUSIONS: We found weekly irinotecan 80 mg/m(2) plus TTD regimen (5-FU 2.25 g/m(2) given as 48-h i.v. infusion) to be a feasible and active combined chemotherapy for the first-line treatment of advanced colorectal cancer.  相似文献   
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