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101.
This study was conducted to establish clinicians’ perspectives of a set of radiology curriculum topics for medical student teaching, which were held to be important by radiologists. A questionnaire was sent to clinicians in all specialties. Forty‐six clinicians (51.1%) out of 90 returned the questionnaires. All curriculum topics were scored above an average of 4 (agree). The five highest ranking curriculum topics in order of importance were: developing a system for viewing chest radiographs (5.59), developing a system for viewing abdominal radiographs (5.56), developing a system for viewing bone and joint radiographs (5.33), distinguishing normal structures from abnormal in chest and abdominal radiographs (5.33) and identifying gross bone or joint abnormalities in skeletal radiographs (5.22). Correlative analysis between speciality groups showed surgical and medical specialities were significantly different in their responses of two learning outcomes: basic knowledge about the contrast media benefits and risks (P= 0.01) and ability to select the most appropriate and the most cost‐effective methods of radiological investigations for clinical situations (P= 0.03). Acute specialities were not significantly different from the other two groups for these two learning outcomes. There was no statistically significant difference for other learning outcomes between the three speciality groups.  相似文献   
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Aberrant Notch signalling has been observed in several human cancers, including acute T-cell lymphoblastic leukaemia and cervical cancer, and is strongly implicated in tumourigenesis. Unregulated Notch signalling in the mouse mammary gland leads to tumour formation. These results raise the possibility that Notch signalling might play a role in human breast cancer. There are currently few reports that address this question directly and this appears to be an area worthy of further investigation.  相似文献   
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BACKGROUND: To optimize burn care for children, the authors introduced a protocol incorporating the use of a bioactive skin substitute, TransCyte (Advanced Tissue Sciences, La Jolla, CA). This study was designed to determine whether this management plan was safe, efficacious, and decreased hospital inpatient length of stay (LOS) compared with conventional burn management in children. METHODS: All pediatric burns greater than 7% total body surface area (TBSA) that occurred after October 1999 underwent wound closure with TransCyte (n = 20). These cases were compared with the previous 20 consecutive burn cases greater than 7% TBSA that received standard therapy. Standard therapy consisted of application of antimicrobial ointments and hydrodebridement. The following information was obtained: burn mechanism, age, size of burn, requirement of autograft, and LOS. Data were analyzed using the student's t test. RESULTS: Data for age, percent TBSA burn and LOS are reported as means +/- SEM. The children who received standard therapy were 2.99 +/- 0.7 years compared with those receiving TransCyte were 3.1 +/- 0.8 years. There was no difference between the treatment groups with regard to percent TBSA burn: standard therapy, 14.3 +/- 1.4% TBSA versus TransCyte, 12.7 +/- 1.3% TBSA. There was no difference in the type of burns in each group, the majority were liquid scald type, 70% in the standard therapy group versus 90% in the TransCyte group. Only 1 child in the TransCyte group required autografting (5%) compared with 7 children in the standard therapy group (35%). Children treated with TransCyte had a statistically 6 significant decreaed LOS compared with those receiving standard therapy, 5.9 +/- 0.9 days versus 13.8 +/- 2.2 days, respectively (P =.002). CONCLUSIONS: This is the first study using TransCyte in children. The authors found that this protocol of burn care was safe, effective, and significantly reduced the LOS. This new approach to pediatric burn care is effective and improves the quality of care for children with burns.  相似文献   
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目的 探究耐亚胺培南铜绿假单胞菌(IRPA)的oprD2基因缺失在天津地区3所三甲医院内的分布以及该菌的克隆流行情况.方法 采用聚合酶链反应(PCR)方法检测60株IRPA的oprD2基因缺失情况,并以基于肠杆菌科基因间重复一致序列PCR(ERIC-PCR)方法对其中的54株进行分子生物学分型.结果 60株IRPA中有38株oprD2基因缺失.且3所医院的oprD2基因缺失率差异无统计学意义(P>0.05),54株IRPA用ERICPCR方法分为30型.结论 IRPA的oprD2基因缺失在天津地区的分布差异无统计学意义,且提示尚有其他原因造成亚胺堵南/西司他丁耐药株流行;个别科室内的IRPA存在克隆流行趋势,应注意监控IRPA在医院内的暴发流行.  相似文献   
106.
Wood  GA; Korkola  JE; Lee  VM; Sarma  DS; Archer  MC 《Carcinogenesis》1997,18(9):1745-1750
Copenhagen (Cop) rats are completely resistant to the chemical induction of mammary adenocarcinomas, but their susceptibility to hepatocarcinogenesis is virtually unknown. Rat liver is a well- characterized and easily manipulated tissue in which to study carcinogenesis. Therefore, if Cop rats are resistant to hepatocarcinogenesis, studies into resistance mechanisms may be feasible. Male Cop and F344 rats, 7-8 weeks old, were initiated using either N-nitrosodiethylamine (DEN) (200 mg/kg, i.p.) or a two-thirds partial hepatectomy (PH) followed by N-methyl-N-nitrosourea (MNU) (60 mg/kg, i.p.). The rats were then promoted using a modified resistant hepatocyte (RH) protocol (a combination of four doses of 2- acetylaminofluorene (2-AAF) and a single dose of CCl4 that provides a selective mitotic stimulus for initiated cells). Six weeks after initiation the rats were killed and liver sections were stained for glutathione S-transferase 7-7 (GST 7-7), a marker for putative preneoplastic hepatocytes. Cop rats were found to be highly resistant, having a approximately 9- and approximately 27-fold smaller percentage of liver area occupied by GST 7-7-positive foci than susceptible F344 rats following initiation by DEN and MNU respectively. Furthermore, gross liver nodules did not form in any of the Cop rats, whereas all F344 rat livers contained nodules. Hepatic necrosis caused by DEN during initiation, and CCl4 during promotion is necessary to stimulate compensatory hepatocyte division. We demonstrated that these agents do indeed increase serum transaminase levels and produce histologic evidence of necrosis in Cop rats. In order for liver foci to grow rapidly in the RH protocol, the surrounding normal hepatocytes must be mito-inhibited by 2-AAF. We found that the degree of mito-inhibition of normal hepatocytes by 2-AAF is the same in Cop and F344 rats. These results show that the Cop rat is highly resistant to the chemical induction of putative preneoplastic liver foci and nodules.   相似文献   
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The Italian multicentre study on very low-birth-weight babies is the first collaborative project in Italy on the health status of newborns weighing 500–1499 g at birth: 634 such babies were admitted in 1987–88 to eight Italian NICUs; 424 infants survived and were followed until two years of age, corrected for prematurity. Logistic regression analysis of pre-admission risk factors of in-hospital mortality identified eight statistically significant variables: birth weight, gestational age, sex, antepartum steroids, I-min Apgar score and, on admission to the NICU, body temperature, pH and absence of spontaneous respiration. Using the equation derived from the logistic model, a theoretical mortality rate was calculated for each centre, predicted on the basis of the local incidence of preadmission risk factors. In no case was the predicted mortality significantly different from the observed one. At two years of age, 8 children were blind and 48 had motor disability. Of these, 46 had cerebral palsy: based on a functional evaluation score 14 had severe (degree 4), 20 intermediate (degree 3) and 12 mild cerebral palsy (degree 2). Among 25 variables entered in a logistic regression as risk factors for cerebral palsy, only periventricular leucomalacia and acidosis were significantly associated with the outcome.  相似文献   
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