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51.
Evolutionary silencing of the human elastase I gene (ELA1)   总被引:6,自引:0,他引:6  
  相似文献   
52.
Superovulation with intrauterine insemination (SO-IUI) has been suggested as an alternative to gamete intrafallopian transfer (GIFT), despite the absence of controlled or comparative trials. We retrospectively analyzed all GIFT and SO-IUI cycles performed concurrently from January 1985 to August of 1987 at a single university center. Pregnancy rates were significantly better for GIFT than SO-IUI (P<0.001), with an odds ratio of 3.25 (P=0.001). Stepwise multiple logistic regression identifield factors that correlate with pregnancy: absence of endometriosis (P=0.05), infertility<3 years' duration (P=0.002), TMS 30×106 (P=0.005), and treatment with GIFT rather than SO-IUI (P=0.001). These data give a first approximation of the increased efficacy of GIFT versus SO-IUI and provide valuable insight into significant confounding variables to be considered when planning a randomized, prospective trial to evaluate these techniques.  相似文献   
53.
Foreign body removal has been developed as a routine radiology department service. Techniques, indications and hazards are described.  相似文献   
54.
Serum androgenic hormones motivate sexual behavior in adolescent boys   总被引:4,自引:0,他引:4  
In order to separate hormonal from social effects on adolescent male sexual behavior, serum hormone assays were performed and questionnaire data on sexual motivation and behavior were collected on a representative sample of 102 boys in grades 8, 9, and 10 of a public school system. Free testosterone was a strong predictor of sexual motivation and behavior, with no additional contribution of other hormones. Including measures of pubertal development and age (indexing the effects of social processes) indicated no additional effects. Free testosterone, therefore, appears to affect sexual motivation directly and does not work through the social interpretation of the accompanying pubertal development.  相似文献   
55.
"Family Medicine Month," a rotation forfirst-year residents, was developed to clarifyfirst-year residents'new roles as family physicians. The rotation explored the meaning and history of the specialty, as well as teaching core family medicine clinical and behavioral skills. Twenty residents who participated in the rotation in 1999 and 2000 indicated satisfaction with the rotation and endorsed its usefulness. They also reported greater self efficacy in performing family practice skills after the rotation, compared with before the rotation. Results suggest that a curriculum based on the context of family medicine as a specialty enhances resident satisfaction and self efficacy.  相似文献   
56.
Lung cancer is not commonly known to metastasise to the perirenal space, with only five such cases previously published. We present an unusual case of perirenal lung metastases manifesting as diffuse perinephric stranding which to our knowledge has not been described before.  相似文献   
57.
The majority of breast cancer research is conducted using established breast cancer cell lines as in vitro models. An alternative is to use cultures established from primary breast tumours. Here, we discuss the pros and cons of using both of these models in translational breast cancer research.  相似文献   
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59.
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning.  相似文献   
60.
The main purpose of this study was to compare rectal and axillary temperature measurements in African children. Altogether 573 sick children were seen in an outpatient setting in rural West Africa. Rectal and axillary temperatures were measured and the parent or guardian was asked if they thought that the child had a raised body temperature. Normal ranges were defined from an age matched population of 203 healthy children. A raised axillary temperature predicted a raised rectal temperature with a sensitivity of 98% and a specificity of 88%. The parents' impression that their child had a fever was a less sensitive (89%) and less specific (59%) indicator of raised rectal temperature. A raised axillary temperature is a good screening test for a raised rectal temperature in African children.  相似文献   
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