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The relationship between diabetes, GERD symptoms and acid-related mucosal damage has not been well studied.  相似文献   
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OBJECTIVE--To determine whether a previously observed association between human immunodeficiency virus type 1 (HIV-1) infection and smoking in Haitian women could be explained by confounding high-risk behaviors. DESIGN AND SETTING--A nested case-control study at a primary care health clinic in Cité Soleil, Haiti. PARTICIPANTS--Women who reported having smoked (n = 89) and randomly selected nonsmokers (n = 329) who had participated in a survey 1 to 12 months earlier evaluating risk factors for HIV-1 infection. MAIN OUTCOME MEASURES--Lifetime sexual practices, smoking, health beliefs and practices, and other factors potentially confounding the relationship between smoking and HIV-1 infection. RESULTS--Compared with nonsmokers, smokers reported higher rates of high-risk behaviors, including more lifetime sex partners (P less than .001), being less likely to be married (P less than .01), and being more likely to have visited folk healers (P less than .01). No intravenous drug use was reported, and no significant differences were noted between smokers and nonsmokers in numbers of past surgical or dental procedures or injections. Adjustment for all factors associated with HIV-1 infection and smoking in regression analyses revealed an independent association between smoking and HIV-1 infection (odds ratio [OR], 3.4; 95% confidence interval [Cl], 1.6 to 7.5). Other factors associated with HIV-1 infection included having more than two life-time sex partners (OR, 3.4; 95% Cl, 1.7 to 6.8) and lower socioeconomic status as reflected by a dirt floor in the home (OR, 8.6; 95% Cl, 3.3 to 22.0). CONCLUSIONS--Smoking is a marker for high-risk sexual behavior and is associated with an increased risk of HIV-1 infection in this population. The persistent association between smoking and HIV-1 infection after adjustment for all known risk factors suggests the possibility of a biologic effect of smoking that warrants further evaluation in other populations.  相似文献   
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HYPOTHESIS: There is a potential for margin distortion associated with the use of a compression plate in specimen mammography (SM) devices. DESIGN: Prospective observational study. SETTING: Two tertiary care teaching hospitals. PATIENTS: Breast biopsy tissue dimensions were recorded in 15 patients undergoing 18 operations before and after SM (group 1). After review of these data, we supervised the positioning of tissue for SM and obtained measurements for 12 breast biopsy specimens from 12 additional patients before and after SM (group 2). MAIN OUTCOME MEASURES: Breast biopsy specimen dimensions recorded before and after SM, including length, width, and depth (the specimen depth along the axis of compression); data on age, menopausal status, hormone therapy, and the presence or absence of calcifications or tumor; and a national telephone survey on technique and understanding of SM at 21 institutions. RESULTS: The specimen depth in group 1 was markedly decreased (P<.001) along the axis of compression. The mean length and width of the specimens were marginally increased by the effect of the SM device. Specimen depth in group 2 was unchanged when minimal pressure was used on the compression plate. Tissue was adequately immobilized in both groups, and all lesions were identified by SM. Our survey revealed that 71% of hospitals reported using firm compression in SM, and diverse techniques were employed. CONCLUSIONS: This study demonstrates the potential for specimen margin distortion with compression SM. Undue specimen compression is common in routine SM. Surgeon oversight in the method of securing the specimen within the SM container will minimize or avoid the potential for margin distortion.  相似文献   
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OBJECTIVE: It has been demonstrated in a number of models that fetal wounds heal with little or no scar. Since collagen is an integral part of the extracellular matrix in adult scar formation, we studied the synthesis and localization of collagen in an in vitro mouse palate model for fetal wound healing. METHODS: Palates, dissected from fetal mice at 15, 16, and 17 days of gestation and from newborn mice, were cultured in medium containing serum (for 8 hours); this was followed by culture in serum-free medium (for 12 hours). One-half of the samples from each age group were wounded in the midline. All samples were placed in serum-free medium containing 20 microCi/mL 3H-proline for 8 hours. In addition, palates from 15-day gestation and from newborn mice were also incubated with transforming growth factor TGF-beta2 (10 ng/mL). Palates were washed with saline, homogenized, and radioactivity was counted. Proline uptake was calculated for each sample as counts per milligram of protein and was subjected to statistical analysis (three-way analysis of variance). Samples of the homogenate were subjected to sodium dodecyl sulfate-gel electrophoresis and Western blotting in order to determine the types of collagen that were synthesized. Immunohistochemical localization of collagen types I, III, and VI was carried out on paraffin-embedded samples from each group. RESULTS: There were no significant differences in proline uptake between wounded mouse palates and nonwounded mouse palates at any age, and there was no histological evidence of regeneration of the palate at the site of the wound. Proline uptake was significantly greater in untreated wounded palates at 15 days' gestation than it was in newborns. After treatment with TGF-beta2, proline uptake was significantly greater in both wounded and nonwounded palates in the newborn group and had no effect on collagen synthesis in palates from 15-day gestation animals. Collagen types I and III were localized in histological specimens using immunohistochemistry and on nitrocellulose using Western blotting. No type VI collagen was demonstrated by Western blotting, but it was localized around blood vessels and on basement membranes using immunohistochemistry. CONCLUSION: Treatment with TGF-beta2 significantly increased collagen synthesis, as assessed by 3H-proline uptake, in cultured palates from newborn mice as compared with palates from untreated newborn mice and from both treated and untreated palates of 15-day gestation mice. These data suggest a differential response to TGF-beta2 by mouse palates as a function of fetal development.  相似文献   
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