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131.
Mora S  Lee IM  Buring JE  Ridker PM 《JAMA》2006,295(12):1412-1419
Context  There are few data directly comparing the effects of physical activity and body weight on cardiovascular biomarkers. Objective  To examine the association of physical activity and body mass index (BMI, defined as weight in kilograms divided by the square of height in meters) alone and in combination with cardiovascular biomarkers. Design, Setting, and Participants  Cross-sectional analysis of 27 158 apparently healthy US women (mean age, 54.7 years) at the time of enrollment (1992-1995) in the Women's Health Study, a randomized, double-blind, placebo-controlled trial of low-dose aspirin and vitamin E in the primary prevention of cardiovascular disease and cancer. Main Outcome Measures  The association of physical activity and BMI with high-sensitivity C-reactive protein (CRP), fibrinogen, soluble intracellular adhesion molecule 1 (ICAM-1), homocysteine, low- and high-density lipoprotein (LDL and HDL) cholesterol, total cholesterol, apolipoprotein A-1 and B100, lipoprotein(a), and creatinine. Results  Lower levels of physical activity and higher levels of BMI were independently associated (P for trend <.001) with adverse levels of nearly all lipid and inflammatory biomarkers. High BMI showed stronger associations with these biomarkers than physical inactivity. For example, using the reference group of physically active, normal weight women (energy expenditure 1000 kcal/week; BMI, 18.5-24.9) and adjusting for age, race, smoking, blood pressure, diabetes, menopausal status, and hormone use, the odds ratios (95% confidence intervals [CIs]) for having CRP >3 mg/L were: for inactive, normal weight women 1.26 (1.15-1.37); active, overweight 2.68 (2.41-2.98); inactive, overweight 3.11 (2.84-3.41); active, obese 8.25 (7.15-9.51); and inactive, obese 9.86 (8.84-10.99). In similar analyses, the odds ratios (95% CIs) for having HDL cholesterol <50 mg/dL were 1.20 (1.11-1.30); 2.25 (2.04-2.49); 2.62 (2.41-2.85); 4.21 (3.68-4.81); and 5.27 (4.77-5.84), respectively, and for having apolipoprotein B100 >120 mg/dL they were 1.21 (1.11-1.33); 1.86 (1.66-2.08); 2.06 (1.88-2.67); 2.35 (2.04-2.70); and 2.33 (2.09-2.59). Fibrinogen, ICAM-1, apolipoprotein A1, total cholesterol, and LDL cholesterol showed similar associations. By contrast, homocysteine, lipoprotein (a), and creatinine showed weak or nonsignificant associations. Conclusions  High BMI was more strongly related to adverse cardiovascular biomarker levels than physical inactivity. However, within BMI categories, physical activity was generally associated with more favorable cardiovascular biomarker levels than inactivity.   相似文献   
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INTRODUCTION Gastric cancer is the third most frequent type of cancer in the world[1]. In Northern Brazil, the State of Pará presents a high incidence of this neoplasia type and its capital, Belém, is ranked eleventh in number of gastric cancers per inh…  相似文献   
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BACKGROUND: Bedside rationing by physicians is controversial. The debate, however, is clouded by lack of information regarding the extent and character of bedside rationing. DESIGN, SETTING, AND PARTICIPANTS: We developed a survey instrument to examine the frequency, criteria, and strategies used for bedside rationing. Content validity was assessed through expert assessment and scales were tested for internal consistency. The questionnaire was translated and administered to General Internists in Norway, Switzerland, Italy, and the United Kingdom. Logistic regression was used to identify the variables associated with reported rationing. RESULTS: Survey respondents (N=656, response rate 43%) ranged in age from 28 to 82, and averaged 25 years in practice. Most respondents (82.3%) showed some degree of agreement with rationing, and 56.3% reported that they did ration interventions. The most frequently mentioned criteria for rationing were a small expected benefit (82.3%), low chances of success (79.8%), an intervention intended to prolong life when quality of life is low (70.6%), and a patient over 85 years of age (70%). The frequency of rationing by clinicians was positively correlated with perceived scarcity of resources (odds ratio [OR]=1.11, 95% confidence interval [CI] 1.06 to 1.16), perceived pressure to ration (OR=2.14, 95% CI 1.52 to 3.01), and agreement with rationing (OR=1.13, 95% CI 1.05 to 1.23). CONCLUSION: Bedside rationing is prevalent in all surveyed European countries and varies with physician attitudes and resource availability. The prevalence of physician bedside rationing, which presents physicians with difficult moral dilemmas, highlights the importance of discussions regarding how to ration care in the most ethically justifiable manner.  相似文献   
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In search of novel purine antimetabolites, a series of 8-substituted methylxanthine derivatives was prepared in order to explore their in vitro anticancer, anti-HIV-1 and antimicrobial activities. The target compounds include: 8-[(3-substituted-4-oxo-thiazolidin-2-ylidene)hydrazino]-1,3-dimethyl (or 1,3,7-trimethyl)-3,7-dihydropurine-2,6-diones 5a-e, 8-[(3,4-disubstituted 2,3-dihydrothiazol-2-ylidene)hydrazino]-1,3,7-trimethyl-3,7-dihydropurine-2,6-diones 6a-d and 8-(5-amino-3-arylpyrazol-1-yl)-1,3-dimethyl- (or 1,3,7-trimethyl)-3,7-dihydropurine-2,6-diones 7a-g. The in vitro anticancer results revealed that compound 5d exhibited a super sensitivity profile towards leukemia K-562 with a GI(50) value of <0.01 microM. Compound 7c showed significant activity against colon cancer HCT-15 and renal cancer CAKI-1 (GI(50) values of 0.47 and 0.78 microM, respectively). Compound 7a displayed high activity against colon cancer HCT-15 (GI(50 )= 0.8 microM). The anti-HIV-1 results indicated that compound 6b displayed a good reduction of viral cytopathic effect (56.69%). The antimicrobial results showed that compound 5a was four times more active than ampicillin against P. aerugenosa (MIC =or< 25 microg/mL), compound 5b had twice the activity of ampicillin, while compounds 5d, 7c and 7f were equipotent to ampicillin. On the other hand, compound 7a was equipotent to ampicillin against P. vulgaris (MIC = 50 microg/mL).  相似文献   
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INTRODUCTION: This study reports the development of a new, accurate and reproducible method which combines histological and computer techniques for the determination of fatty load in cholesterol-fed rabbits. METHODS: New Zealand male rabbits were randomly divided into three groups. The animals in group 1 (control) received neither cholesterol nor drugs. Those in group 2 received a 2% cholesterol diet for 30 days, followed by a normal diet for 45 days. In addition during the latter period (day 31 to day 75) animals received 200 g of chopped carrots each morning. The rabbits in group 3 followed the same dietary regime as those in group 2 except that 8.36 mg of simvastatin and 1.76 g cholestyramine were mixed with their carrots. On the 76th day, the animals were sacrificed and their blood and hearts were collected. Histological sections (15 microm thick) of hearts were cut at 90 degrees to the long axis using a motorized freezing microtome. Every tenth section was mounted on a glass slide and stained with Oil Red O. A total of hundred slides prepared from each heart were scanned into a computer and the area stained by Oil Red O was measured, giving a measure of the total fatty "load" in each heart. RESULTS: There was a highly significant increase in the coronary fatty deposits in the hearts of the animals fed with cholesterol rich diet (group 2) as compared to the control rabbits in group 1. Treatment of rabbits with simvastatin plus cholestyramine (group 3) significantly reduced the coronary lipids load. DISCUSSION: The combination of histological and computer-based techniques used in this study provides an accurate and reproducible method for the quantitation of fatty deposits in rabbit coronary vessels. This report is based on the measurement of coronary lipid depositions rather than aortic lesions. It also overcomes the shortcoming of the majority of the earlier published methods which are generally limited to the measurement of fatty plaques in only few major coronary vessels, totally neglecting the many small distributive vessels which are often responsible for cardiac ischemic disease.  相似文献   
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Background  

This study evaluates the existence of numerical alterations of chromosome 17 and TP53 gene deletion in gastric adenocarcinoma. The p53 protein expression was also evaluated, as well as, possible associations with clinicopathological characteristics.  相似文献   
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