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991.
992.
Fear appeal approach has been used in health promotion, but its effectiveness has been mixed. It has not been well applied to HIV prevention among men who have sex with men (MSM). The present study developed and evaluated the relative efficacy of three online interventions (SC: STD-related cognitive approach, SCFI: STD-related cognitive plus fear appeal imagery approach, Control: HIV-related information based approach) in reducing prevalence of unprotected anal intercourse (UAI) among 396 MSM using a randomized controlled trial design. Participants’ levels of fear-related emotions immediately after watching the assigned intervention materials were also assessed. Participants were evaluated at baseline and 3 months after the intervention. Results showed that participants in the SCFI scored significantly higher in the instrument assessing fear after the watching the intervention materials. However, no statistically significant differences were found across the three groups in terms of UAI at Month 3. Some significant within-group reductions in some measures of UAI were found in three groups. Further studies are warranted to test the role of fear appeal in HIV prevention.  相似文献   
993.
This paper examines the relationship between circumcision status and timing of sexual debut among unmarried youth in Sub-Saharan Africa using Demographic and Health Surveys. Results from survival analysis indicate that the association between circumcision and timing of first sex is place and context specific. Compared to uncircumcised, circumcised men in Rwanda, Uganda and Namibia hasten sexual initiation, whilst circumcised youth in Ethiopia and Mali delayed sex initiation. In Togo however, we found parity in timing to sexual debut. Our multivariate results reveal that, knowledge of HIV/AIDS risk and educational level also feed into the association between circumcision and timing of sex initiation- implying that efforts to prevent new HIV infection through circumcision could benefit from a proper understanding of how diverse set of factors interact in specific contexts to shape youth’s decisions to initiate early sex.  相似文献   
994.
Investments in community-based HIV prevention programs in Ontario over the past two and a half decades are assumed to have had an impact on the HIV epidemic, but they have never been systematically evaluated. To help close this knowledge gap, we conducted a macro-level evaluation of investment in Ontario HIV prevention programs from the payer perspective. Our results showed that, from 1987 to 2011, province-wide community-based programs helped to avert a total of 16,672 HIV infections, saving Ontario’s health care system approximately $6.5 billion Canadian dollars (range 4.8–7.5B). We also showed that these community-based HIV programs were cost-saving: from 2005 to 2011, every dollar invested in these programs saved about $5. This study is an important first step in understanding the impact of investing in community-based HIV prevention programs in Ontario and recognizing the impact that these programs have had in reducing HIV infections and health care costs.  相似文献   
995.
The relationship between level of childhood abuse (physical and emotional) and sexual risk behavior of sexually transmitted disease clinic patients in St. Petersburg, Russia was examined through path analyses. Mediating variables investigated were: Alcohol Use Disorder Identification Test (AUDIT), drinking motives (for social interaction, to enhance mood, to facilitate sexual encounters), intimate partner violence (IPV), anxiety, and depression symptoms. Results showed a significant indirect effect of childhood abuse on women’s sexual risk behavior: higher level of childhood abuse was associated with a greater likelihood of IPV, motivations to drink, leading to higher AUDIT scores and correlated to higher likelihood of having multiple, new or casual sexual partner(s). No significant effect was identified in paths to condom use. Among men, childhood abuse had no significant effect on sexual risk behavior. Reduction in alcohol-related sexual risk behavior may be achieved by addressing the effects of childhood abuse among female participants.  相似文献   
996.
The aim of this meta-analysis was to explore whether the constructs in the theory of planned behaviour (TPB; i.e., attitude, subjective norm, perceived behavioural control, intention) explain condom use behaviour among men who have sex with men (MSM). Electronic databases were searched for studies that measured TPB variables and MSM condom use. Correlations were meta-analysed using a random effects model and path analyses. Moderation analyses were conducted for the time frame of the behavioural measure used (retrospective versus prospective). Attitude, subjective norm and perceived behavioural control accounted for 24.0 % of the variance in condom use intention and were all significant correlates. Intention and PBC accounted for 12.4 % of the variance in condom use behaviour. However, after taking intention into account, PBC was no longer significantly associated with condom use. The strength of construct relationships did not differ between retrospective and prospective behavioural assessments. The medium to large effect sizes of the relationships between the constructs in the TPB, which are consistent with previous meta-analyses with different behaviours or target groups, suggest that the TPB is also a useful model for explaining condom use behaviour among MSM. However, the research in this area is rather small, and greater clarity over moderating factors can only be achieved when the literature expands.  相似文献   
997.
998.
The brand new 2016 ESC guidelines for the treatment of acute and chronic heart failure continue to give a prominent place to mineralocorticoid receptor antagonists in the treatment of chronic heart failure with reduced ejection fraction (HFrEF). In the prevention of HF hospitalization and death, a class I, level of recommendation A, is given to MRAs for patients with HFrEF, who remain symptomatic despite treatment with an ACE-inhibitor and a beta-blocker and have an LVEF below 35 %. This recommendation is primarily based on two landmark trials, the RALES trial (for spironolactone) and the EMPHASIS-HF trial (for eplerenone). A crucial question is, however, why MRAs are advised only in “third place,” i.e., after optimal up-titration of ACE-inhibitors and beta-blockers. We wonder whether MRAs could not or should not be given earlier in the treatment of HFrEF, namely before or together with the up-titration of ACE-inhibitors and beta-blockers. Several arguments to support this plea are described in this short paper.  相似文献   
999.
Heart failure is a major health problem worldwide and, despite effective therapies, is expected to grow by almost 50 % over the next 15 years. Five-year mortality remains high at 50 % over 5 years. Because of the economic burden and large impact on quality of life, substantial effort has focused on treatments with multiple medical (beta-blockers, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (ARB), aldosterone antagonists, and combination of ARB/neprilysin blockers, ivabradine) and device therapies (ICD, CRT) which have been implemented to reduce disease burden and mortality. However, in the past decade only two new medical therapies and no devices have been approved by the US FDA for the treatment of heart failure. This review highlights the preclinical and clinical literature, and the implantation procedure, related to a relatively new therapeutic device for heart failure; cardiac contractility modulation (CCM). CCM delivers a biphasic high-voltage bipolar signal to the RV septum during the absolute refractory period, eliciting an acute increase in global contractility, and chronically producing a sustained improvement in quality of life, exercise tolerance, and heart failure symptoms. The technology is used commercially in Europe with nearly 3000 patients implanted worldwide. Indications include patients with reduced EF and normal or slightly prolonged QRS duration, thus filling an important therapeutic gap among the 2/3 of patients with heart failure who do not meet criteria for CRT. The mechanism by which CCM provides benefit can be seen at the cellular level where improved calcium handling (phosphorylation of phospholamban, upregulation of SERCA-2A), reversal of the fetal myocyte gene program associated with heart failure, and reverse remodeling are observed. Recent retrospective studies indicate a long-term mortality benefit. A pivotal randomized controlled study is currently being completed in the USA. CCM appears to be an effective, safe technology for the treatment of heart failure with reduced ejection fraction.  相似文献   
1000.
We are accustomed to treating aging as a set of things that go wrong with the body. But for more than twenty years, there has been accumulating evidence that much of the process takes place under genetic control. We have seen that signaling chemistry can make dramatic differences in life span, and that single molecules can significantly affect longevity. We are frequently confronted with puzzling choices the body makes which benefit neither present health nor fertility nor long-term survival. If we permit ourselves a shift of reference frame and regard aging as a programmed biological function like growth and development, then these observations fall into place and make sense. This perspective suggests that aging proceeds under control of a master clock, or several redundant clocks. If this is so, we may learn to reset the clocks with biochemical interventions and make an old body behave like a young body, including repair of many of the modes of damage that we are accustomed to regard as independent symptoms of the senescent phenotype, and for which we have assumed that the body has no remedy.  相似文献   
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