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目的 研究镉相关翻译启动因子TIF3对多种细胞肿瘤相关基因表达的影响,探索镉的分子致癌机制。方法应用TIF3基因真核细胞稳定表达系统和Western blot检测技术,用各种单克隆抗体检测细胞肿瘤相关基因蛋白的表达情况。结果 相对于载体转染中国仓鼠卵巢(CHO)对照细胞,在4株具有高效稳定表达TIF3编码蛋白质的CHO细胞系中均有pan—ras癌基因蛋白异常表达,其编码蛋白(21kDa)含量均明显高于对照组;其余肿瘤相关基因蛋白如c—myc.c-jun,MDM2,ODC,P16,p53,Cyclin D1的表达蛋白在TIF3转基因细胞与对照细胞之间未见明显差别。结论 镉相关翻译启动因子TIF3是一种镉应答原癌基因,TIF3的超额表达可导致Ras癌基因蛋白异常表达,这可能是镉应答原癌基因TIF3的分子致癌机制。  相似文献   
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We report the beneficial effects of enzyme replacement therapywith mannose-terminated human glucocerebrosidase (‘Ceredase’)in a patient suffering from transfusion-dependent bone marrowfailure due to Gaucher's disease. Treatment with low-dose enzymeinfusions, given twice weekly, rapidly reversed the haematopoieticfailure and incapacitating skeletal disease. It appears likelythat prior splenectomy favourably influenced the response tothis therapy.  相似文献   
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Baker  DE; Silver  TM; Coran  AG; McMillin  KI 《Radiology》1986,161(2):341-344
At the authors' medical center, most patients with postappendectomy fluid collections are treated conservatively. Thirty-two (15%) of 216 children underwent postoperative sonography following appendectomies. In ten patients (31%), a total of 16 fluid collections were found on the initial postoperative sonogram. In the seven patients (70%) whose fluid collections were confined to the pelvis, the condition was treated conservatively and it resolved in 2-9 weeks. In three patients, fluid collections required surgical drainage and proved to be abscesses. In two of the three patients, abscesses were multiple and widely distributed in the abdomen, and the patients were clinically ill. The authors conclude that clinically symptomatic fluid collections develop postoperatively in approximately 5% of children who have undergone appendectomy for acute appendicitis and that the size and course of the fluid collection can be objectively monitored using sonography. Such fluid collections confined to the pelvis ultimately resolve with conservative, nonoperative therapy, although resolution may take up to 2 months.  相似文献   
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To determine the prevalence of low folic acid levels in infants with marasmic malnutrition and to study its response to daily supplements of folic acid, a group of 80 malnourished infants 2 to 22 months of age were studied. In 12.5% of the group, serum folic acid levels were under 3ug/l and in 16.3%, red cell folic acid levels were under 140ug/l. In a sub group of 28 infants we determined the levels of folic acid on admission and discharge from a nutritional recovery center. During their hospital stay (median 117 days with a range of 94 to 130) infants received exclusively cow's milk with a daily supplement of 100ug of folic acid. On discharge, a significant increase of serum folic levels to normal values was observed. A similar improvement, but not to the same extent, was appreciated in red cell folates. Inadequate quantity of supplementation or short time of observation could explain the lack of complete correction in the erythrocyte folic concentration.  相似文献   
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The Department of Preventive Medicine and Community Health at the State University of New York, Health Science Center at Brooklyn (SUNY, HSCB) instituted an eight-week third world international health elective for fourth year medical students in 1980. Since that time, ninety students have participated. The purposes of this elective are to provide fourth year medical students with an opportunity to observe and study the structure and functions of a health care delivery system in a third world country, to provide medical service, and to have a crosscultural experience. The emphasis in this elective is on public health, preventive medicine, and primary care. There is a high level of student competition for this elective, with 46.9% of applicants having been accepted over a fifteen-year period. Although women comprise 40% of the average medical school class, they represent 50% of participants in this elective program. The percentage of African-American and Hispanic students has been 20%. These two minority groups represented from 8% to 10% of the student body during the period under study. Careful screening, including an examination of academic records and personal interviews, has resulted in the selection of highly motivated, adaptable, and dedicated students who have performed well at overseas sites. Student satisfaction levels with this elective are extremely high, with most rating it the best experience of their medical school years. Students undergo extensive preparation prior to going overseas. This covers issues related to individual health and safety, travel and lodging, and the nature of the host country culture, health care system, and assignment site. Our students are especially experienced at cross-cultural understanding because of the unusual diversity of the patients they treat in Brooklyn, and the ethnic diversity of local hospital staffs and the medical school class. This Brooklyn experience in cross-cultural understanding has been cited by many participants as having been the best preparation for functioning in a foreign culture. The Alumni Fund of the College of Medicine has strongly and consistently supported this elective both with philosophical commitment and financial grants to help defray travel costs. This type of support is unusual among medical schools in New York City. Overseas preceptors have willingly given of their time and institutional resources to make these experiences available and meaningful for students.  相似文献   
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