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991.
Retinal degeneration is the leading cause of visual impairment in older adults. An association between retinal degeneration and fungicide use was observed previously among farmer pesticide applicators in the Agricultural Health Study, a large study of farm families from Iowa and North Carolina. The objective of this investigation was to determine whether wives of these farmer pesticide applicators were at increased risk of retinal degeneration. Self-reported cross-sectional data obtained via questionnaire between 1993 and 1997 from 31,173 wives were used. Associations of specific pesticides and groups of pesticides based on function (fungicides, herbicides, insecticides, and fumigants) or chemical structure (organophosphates, organochlorines, and carbamates) with eye disorders were evaluated using logistic and hierarchical logistic regression analyses. Self-reported retinal degeneration was associated with the wife's fungicide use (odds ratio = 1.9, 95% confidence interval: 1.2, 3.1) after adjustment for age and state of residence. Specific fungicides that appeared to drive this association were maneb or mancozeb and ziram. No associations between pesticide use and other eye disorders were found. Although these findings for retinal degeneration are based solely on self-reported disease, they are consistent with those reported for farmer pesticide applicators. These findings suggest that exposure to some fungicides and other pesticides may increase the risk of retinal degeneration and warrant further investigation.  相似文献   
992.
Arsenic exposure is a likely cause of blackfoot disease and a potential risk factor for atherosclerosis. The authors performed a systematic review of the epidemiologic evidence on the association between arsenic and cardiovascular outcomes. The search period was January 1966 through April 2005. Thirteen studies conducted in general populations (eight in high-arsenic areas in Taiwan, five in other countries) and 16 studies conducted in occupational populations were identified. Exposure was assessed ecologically in most studies. In Taiwan, relative risks comparing the highest arsenic exposure category with the lowest ranged from 1.59 to 4.90 for coronary disease, from 1.19 to 2.69 for stroke, and from 1.66 to 4.28 for peripheral arterial disease. In other general populations, relative risks ranged from 0.84 to 1.54 for coronary disease, from 0.69 to 1.53 for stroke, and from 0.61 to 1.58 for peripheral arterial disease. In occupational populations, relative risks ranged from 0.40 to 2.14 for coronary disease mortality and from 0.30 to 1.33 for stroke mortality. Methodologic limitations, however, limited interpretation of the moderate-to-strong associations between high arsenic exposure and cardiovascular outcomes in Taiwan. In other populations or in occupational settings, the evidence was inconclusive. Because of the high prevalence of arsenic exposure, carefully performed studies of arsenic and cardiovascular outcomes should be a research priority.  相似文献   
993.
This study examined the interaction of 2 diets (high protein, reduced carbohydrates vs. low protein, high carbohydrates) with exercise on body composition and blood lipids in women (n = 48, approximately 46 y old, BMI = 33 kg/m(2)) during weight loss. The study was a 4-mo weight loss trial using a 2 x 2 block design (Diet x Exercise). Diets were equal in total energy (7.1 MJ/d) and lipids ( approximately 30% energy intake) but differed in protein content and the ratio of carbohydrate:protein at 1.6 g/(kg . d) and <1.5 (PRO group) vs. 0.8 g/(kg . d) and >3.5 (CHO group), respectively. Exercise comparisons were lifestyle activity (control) vs. a supervised exercise program (EX: 5 d/wk walking and 2 d/wk resistance training). Subjects in the PRO and PRO + EX groups lost more total weight and fat mass and tended to lose less lean mass (P = 0.10) than the CHO and CHO + EX groups. Exercise increased loss of body fat and preserved lean mass. The combined effects of diet and exercise were additive for improving body composition. Serum lipid profiles improved in all groups, but changes varied among diet treatments. Subjects in the CHO groups had larger reductions in total cholesterol and LDL cholesterol, whereas subjects in the PRO groups had greater reductions in triacylglycerol and maintained higher concentrations of HDL cholesterol. This study demonstrated that a diet with higher protein and reduced carbohydrates combined with exercise additively improved body composition during weight loss, whereas the effects on blood lipids differed between diet treatments.  相似文献   
994.
Cancer is now the leading cause of death in Minnesota. Half of all Minnesotans will develop a potentially life-threatening cancer in their lifetime, and the number of people diagnosed with cancer is projected to increase by 22% between 2000 and 2010. In 2003, health care providers, health plan representatives, patient care advocates, public health professionals, members of volunteer organizations, and cancer researchers came together to begin crafting the state's first plan to address the full spectrum of cancer control--from prevention and early detection to treatment, palliative care, and survivorship. The resulting plan is intended to serve as a framework for action by policymakers, planners, health care providers, and others, and is grounded in the notion that better integration and coordination of cancer control activities and programs will result in more effective efforts to address the burden of cancer in Minnesota.  相似文献   
995.
Perceived naturalness and acceptance of genetically modified food   总被引:2,自引:0,他引:2  
This study examines people's acceptance of genetically modified (GM) food. Results suggest that GM acceptance depends most on how natural the genetically modified product is perceived and not directly on how natural the non-GM product is seen. A GM product that is perceived as more natural is more likely to be accepted than a GM product that is perceived as less natural. The extent to which GM affects the perceived naturalness of a product partly depends on the kind of product.  相似文献   
996.
Ricin toxin is a plant-derived ribosome inactivating protein (RIP) of extraordinary toxicity. Vaccination using ricin toxoid or its A chain (RTA) is protective in animals but both vaccines have two potential toxicities, RIP and vascular leak syndrome (VLS). Previously we described three recombinant RTA constructs from which both toxicities were eliminated by site-specific mutations. One mutant, V76M/Y80A, RiVax, has now been further characterized for immunogenicity and toxicity in animals. We have found that RiVax is safe at doses of at least 8 mg in mice, 800-fold higher than the protective dose, and induces neutralizing antibodies in both mice and rabbits.  相似文献   
997.
Studies were conducted to explore altered substrate utilization and metabolism in GLUT4 null mice. Liver fatty acid synthase mRNA and fatty acid synthesis rates were dramatically increased in GLUT4 null mice compared with control mice and were supported by increased rates of the pentose phosphate pathway oxidative phase and sterol regulatory binding protein mRNA expression. Increased GLUT2 protein content, glucokinase mRNA, and glucose-6-phosphate in GLUT4 null mice may provide substrate for the enhanced fatty acid synthesis. Increased fatty acid synthesis, however, did not lead to hepatic triglyceride accumulation in GLUT4 null mice because of increased hepatic triglyceride secretion rates. GLUT4 null mice rapidly cleared orally administered olive oil, had reduced serum triglyceride concentrations in the fed and the fasted state, and increased skeletal muscle lipoprotein lipase when compared with controls. Oleate oxidation rates were increased in GLUT4 null skeletal muscle in association with mitochondrial hyperplasia/hypertrophy. This study demonstrated that GLUT4 null mice had increased hepatic glucose uptake and conversion into triglyceride for subsequent use by muscle. The ability of GLUT4 null mice to alter hepatic carbohydrate and lipid metabolism to provide proper nutrients for peripheral tissues may explain (in part) their ability to resist diabetes when fed a normal diet.  相似文献   
998.
The goal of abolishing female genital cutting (FGC, or also FGM or 'female circumcision') requires that the socio-cultural dynamics of the practice be well understood if behavioural change is to be accomplished. This paper, based on the literature and the author's ethnographic research in Sudan, reports on the research issues of studying the variation in and complexity of cutting practices and their cultural correlates, arguing for multiple approaches and methods. It highlights directions for future research.  相似文献   
999.
Effectiveness of a clinical ladder program   总被引:1,自引:0,他引:1  
A 5-hospital system shares results of the evaluation of a clinical ladder program. Improvements were noted in overall satisfaction with the program, nurse retention of those who participated in the program, and costs savings due to decreased turnover. The authors point out the importance of evaluating the effectiveness of advancement programs for nurses. The analysis of a clinical ladder program in relation to costs, financial impact, and benefits helps to justify the salary increments for the ladder programs. This article provides the nurse executive with appropriate justification and outcome data to effectively champion these programs.  相似文献   
1000.
Health effects of garlic   总被引:6,自引:0,他引:6  
Garlic has long been used medicinally, most recently for its cardiovascular, antineoplastic, and antimicrobial properties. Sulfur compounds, including allicin, appear to be the active components in the root bulb of the garlic plant. Studies show significant but modest lipid-lowering effects and antiplatelet activity. Significant blood pressure reduction is not consistently noted. There is some evidence for antineoplastic activity and insufficient evidence for clinical antimicrobial activity. Side effects generally are mild and uncommon. Garlic appears to have no effect on drug metabolism, but patients taking anticoagulants should be cautious. It seems prudent to stop taking high dosages of garlic seven to 10 days before surgery because garlic can prolong bleeding time.  相似文献   
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