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161.
Stewart KJ Bacher AC Turner K Lim JG Hees PS Shapiro EP Tayback M Ouyang P 《American journal of preventive medicine》2005,28(1):9-18
BACKGROUND: Older people with elevated blood pressure (BP) often have metabolic syndrome, a clustering of central obesity, insulin resistance, dyslipidemia, and hypertension. Exercise reduces many of these risk factors. This study examined whether the benefits of exercise on cardiovascular and metabolic disease risk factors are mediated by exercise-induced changes in fitness or body composition. METHODS: Randomized controlled trial, comprising 6 months of exercise training, conducted between July 1999 and November 2003. Participants included men and women (n =115) aged 55 to 75 years with untreated systolic blood pressure (SBP) of 130 to 159 or diastolic blood pressure of (DPB) 85 to 99 mm Hg. Fitness measures included BP, lipids, lipoproteins, insulin, and glucose; peak oxygen uptake and muscle strength; and body composition measured by anthropometry, dual-energy x-ray absorptiometry, and magnetic resonance imaging. RESULTS: A total of 51 men and 53 women completed the trial. Exercise significantly increased aerobic and muscle fitness, lean mass, and high-density lipoprotein cholesterol and reduced total and abdominal fat. DBP was reduced more among exercisers. There were no associations among changes in fitness with risk factors. Reductions in total body and abdominal fat and increases in leanness, largely independent of weight loss, were associated with improved SBP, DBP, total cholesterol, very low-density lipoprotein cholesterol, triglycerides, lipoprotein(a), and insulin sensitivity. At baseline, 42.3% of participants had metabolic syndrome. At 6 months, nine exercisers (17.7%) and eight controls (15.1%) no longer had metabolic syndrome, whereas four controls (7.6%) and no exercisers developed it (p =0.06). CONCLUSIONS: Although exercise improved fitness, the reductions in total and abdominal fatness and increase in leanness were more strongly associated with favorable changes in risk factors for cardiovascular disease and diabetes, including those that constitute metabolic syndrome. 相似文献
162.
Cushing's syndrome is a consequence of primary or, more commonly, secondary oversecretion of cortisol. Cardiovascular disease is the major cause of morbidity and mortality in Cushing's syndrome, and excess risk remains even in effectively treated patients. The cardiovascular consequences of cortisol excess are protean and include, inter alia, elevation of blood pressure, truncal obesity, hyperinsulinemia, hyperglycemia, insulin resistance, and dyslipidemia. This review analyses the relationship of cortisol excess, both locally and at tissue level, to these cardiovascular risk factors, and to putative mechanisms for hypertension. Previous studies have examined correlations between cortisol, blood pressure, and other parameters in the general population and in Cushing's syndrome. This review also details changes induced by short-term cortisol administration in normotensive healthy men. 相似文献
163.
Currie JN Wallman L Chien J Snell L Cluff M Scrivener K Benson EM 《The Medical journal of Australia》2005,182(2):73-75
We report an outbreak of a "rash" syndrome in patients attending methadone clinics in New South Wales. It presents with a pruritic, exanthematous or purpuric rash involving the trunk, limbs, palms and soles, which develops over a week and proceeds in most patients to desquamation (mainly of palms and soles) persisting for 3-4 weeks. Mucosae are not involved, and patients are generally systemically well. To date, the rash has affected 22% of 316 patients attending one methadone clinic in western Sydney, as well as patients in clinics elsewhere in Sydney and rural NSW. The aetiology is as yet unknown. 相似文献
164.
165.
Oral administration of second-generation immunomodulatory oligonucleotides induces mucosal Th1 immune responses and adjuvant activity 总被引:7,自引:0,他引:7
CpG DNA induces potent Th1 immune responses through Toll-like receptor 9. In the present study, we used oligonucleotides consisting of a novel 3'-3'-linked structure and synthetic stimulatory motifs, referred as second-generation immunomodulatory oligonucleotides (IMOs). The stimulatory motifs included: CpR, YpG, or R'pG (R = 2'-deoxy-7-deazaguanosine, Y = 2'-deoxy-5-hydroxy-cytidine, and R' = 1-[2'-deoxy-beta-d-ribofuranosyl]-2-oxo-7-deaza-8-methyl-purine). We evaluated the stability of orally administered IMOs in the gastrointestinal (GI) environment and their ability to induce mucosal immune responses in mice, and compared these characteristics with those of a conventional CpG DNA. The IMOs were significantly more stable than CpG DNA following oral administration, and IMOs induced stronger local and systemic immune responses as determined by MIP-1beta, MCP-1, IP-10, and IL-12 production. Mice orally immunized with ovalbumin (OVA) and IMO had higher levels of IgG2a antibodies in serum and IgA antibodies in intestinal mucosa than did mice immunized with OVA and CpG DNA. These studies demonstrate that IMOs are more stable than CpG DNA in the GI tract and can induce more potent mucosal Th1 adjuvant responses. IMOs may prove to be effective oral adjuvants, able to promote strong systemic and mucosal immune responses to oral vaccines and antigens for therapeutic and prophylactic applications. 相似文献
166.
167.
BACKGROUND: Few school-based interventions have been evaluated to assess health awareness among children in rural southern areas. The purpose of this controlled investigation was to increase health awareness among middle school-aged children residing in a racially diverse rural community in Mississippi. METHODS: This investigation assessed health knowledge before and after a 16-week school-based intervention in 205 fifth-grade students. Height, weight, BMI, body composition, waist circumference, dietary intake, blood lipids and lipoprotein concentrations, blood glucose concentrations, and resting blood pressure were measured to enhance student awareness of cardiovascular disease risk factors. Values in the intervention school were compared with those obtained simultaneously in a control school within the same community. RESULTS: The school-based intervention was effective in increasing health knowledge in the intervention as compared with the control school. Secondarily, it was effective in improving certain dietary behaviors. Utilizing health care professionals in the classroom to teach students appropriate lifestyles and actually measuring cardiovascular risk factors to increase awareness among students was effective in increasing overall health knowledge. CONCLUSIONS: Health knowledge of rural adolescents can be increased through partnerships with schools and multidisciplinary teams of health care professionals. Ongoing efforts to reduce childhood obesity and cardiovascular disease risk factors are urgently needed, and information obtained during this investigation may be used in planning school-based interventions in other diverse, rural communities. 相似文献
168.
Mark A. Nelson John P. Coghlan Derek A. Denton Judith A. Whitworth Bruce A. Scoggins 《Clinical and experimental pharmacology & physiology》1985,12(2):155-159
The role of serotonin (5HT) in the pathogenesis of ACTH-induced hypertension in sheep has been examined. The pressor responses to injections of 5HT (0.1-30 micrograms/kg) were similar in normotensive and hypertensive sheep. Prior treatment with the 5HT2 receptor antagonist ketanserin had no effect on the development of hypertension produced by ACTH administration. 相似文献
169.
Summary Previously reported studies have shown clear differences among strains of inbred mice in response to a variety of novel situations and to certain pharmacologic agents. The purpose of the present study was to test the tenability of the hypothesis that such behavioral differences between genetically distinct groups may be a function of arousal system differences. To achieve this objective while using a pharmacologic method, the investigators assumed: (1) that the state of arousal of the organism is isomorphic to the effects of certain depressant and excitatory drugs; and (2) that a direct relation exists between quantitative differences in overt behavior and the cumulative effects of the drug. Four drugs were selected which could produce measurable changes on an arousal continuum from sleep (pentobarbital), through quiescence (chlorpromazine) and alertness (amphetamine), to convulsions (pentylenetetrazol). Similarly, four strains of mice were selected which show related differences in normal activity: BALB/c, C3H/An, DBA/2, and C57BL/6.Although significant strain differences appeared in base-activity levels as well as in the responses to the standard doses of the drugs and of the placebo, only the responses to pentobarbital and amphetamine were entirely consistent with an arousal hypothesis. The duration of the effect of pentylenetetrazol was also consistent but the latency of that effect was not. At best, the effect of chlorpromazine was that of a mild stimulant, contrary to the justification for its inclusion in this study. Clearly the rigid adherence to any one theoretical orientation in the interpretation of strain-activity phenomena is premature.This research was supported by an AEC contract, No. AT (40-1)-2186, with Vanderbilt University, Nashville, Tenn. 相似文献
170.