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Kaplan RC Heckbert SR Koepsell TD Furberg CD Polak JF Schoen RE Psaty BM 《Journal of the American Geriatrics Society》2001,49(2):126-133
OBJECTIVES: We sought to estimate the incidence of hospitalization for upper and lower gastrointestinal bleeding among older persons and to identify independent risk factors. DESIGN: Prospective cohort study. SETTING: The Cardiovascular Health Study (CHS). PARTICIPANTS: 5,888 noninstitutionalized men and women age 65 years or older in four U.S. communities enrolled in the CHS. MEASUREMENTS: Gastrointestinal bleeding events during the period 1989 through 1998 were identified using hospital discharge diagnosis codes and confirmed by medical records review. Risk-factor information was collected in a standardized fashion at study baseline and annually during follow-up. RESULTS: Among CHS participants (mean baseline age 73.3 years, 42% male), the incidence of hospitalized gastrointestinal bleeding was 6.8/1,000 person-years. In multivariate analyses, advanced age, male sex, unmarried status, cardiovascular disease, difficulty with daily activities, use of multiple medications, and use of oral anticoagulants were independent risk factors. Compared with nonsmokers, subjects who smoked more than half a pack per day had a multivariate-adjusted hazard ratio (HR) of 2.14 (95% confidence interval [CI] = 1.22-3.75) for upper gastrointestinal bleeding and a multivariate-adjusted HR of 0.21 (95% CI = 0.03-1.54) for lower gastrointestinal bleeding. Aspirin users did not have an elevated risk of upper gastrointestinal bleeding (HR = 0.76, 95% CI = 0.52-1.11), and users of other nonsteroidal anti-inflammatory drugs had a HR of 1.54 (95 % CI = 0.99-2.36). Low ankle-arm systolic blood pressure index was associated with higher risk of gastrointestinal bleeding among subjects with clinical cardiovascular disease but not among those without clinical cardiovascular disease. CONCLUSION: This study identifies risk factors for gastrointestinal bleeding, such as disability, that may be amenable to modification. The findings will help clinicians to identify older persons who are at high risk for gastrointestinal bleeding. 相似文献
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Guidelines for the conduct of clinical trials for spinal cord injury (SCI) as developed by the ICCP panel: clinical trial outcome measures 总被引:3,自引:0,他引:3
Steeves JD Lammertse D Curt A Fawcett JW Tuszynski MH Ditunno JF Ellaway PH Fehlings MG Guest JD Kleitman N Bartlett PF Blight AR Dietz V Dobkin BH Grossman R Short D Nakamura M Coleman WP Gaviria M Privat A;International Campaign for Cures of Spinal Cord Injury Paralysis 《Spinal cord》2007,45(3):206-221
An international panel reviewed the methodology for clinical trials of spinal cord injury (SCI), and provided recommendations for the valid conduct of future trials. This is the second of four papers. It examines clinical trial end points that have been used previously, reviews alternative outcome tools and identifies unmet needs for demonstrating the efficacy of an experimental intervention after SCI. The panel focused on outcome measures that are relevant to clinical trials of experimental cell-based and pharmaceutical drug treatments. Outcome measures are of three main classes: (1) those that provide an anatomical or neurological assessment for the connectivity of the spinal cord, (2) those that categorize a subject's functional ability to engage in activities of daily living, and (3) those that measure an individual's quality of life (QoL). The American Spinal Injury Association impairment scale forms the standard basis for measuring neurologic outcomes. Various electrophysiological measures and imaging tools are in development, which may provide more precise information on functional changes following treatment and/or the therapeutic action of experimental agents. When compared to appropriate controls, an improved functional outcome, in response to an experimental treatment, is the necessary goal of a clinical trial program. Several new functional outcome tools are being developed for measuring an individual's ability to engage in activities of daily living. Such clinical end points will need to be incorporated into Phase 2 and Phase 3 trials. QoL measures often do not correlate tightly with the above outcome tools, but may need to form part of Phase 3 trial measures. 相似文献
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Functional electrical stimulation for grasping and walking: indications and limitations 总被引:10,自引:0,他引:10
This review describes the state of art in the field of Functional Electrical Stimulation (FES) and its impact on improving grasping and walking functions in acute and chronic Spinal Cord Injured (SCI) patients. It is argued that during the early rehabilitation period the FES systems with surface stimulation electrodes should be used to assist training of hand and leg movements in SCI patients. Our clinical trials have shown that a number of acute SCI patients with impaired walking and grasping functions could improve these functions due to training with an adjustable FES system to the point that they finally did not need the FES system to carry out these tasks. Other acute SCI patients, who did not recover the desired function, were enabled to perform either walking or grasping with the FES assistance. We believe that the subjects who can perform grasping or walking with the help of FES, and still use the neuroprosthesis 6 months after being subjected to the FES training, should consider the FES system as a prosthetic device in Activities of Daily Living (ADL). Despite the significant technical progress achieved in the last 10 to 15 years in the FES field, there is a general consensus that these systems are not sufficiently advanced and that they need further development. The limited acceptance of the FES technology can be in part explained by the fact that it is not completely mature and that the patients still require daily assistance to use the FES systems. Nevertheless the present FES treatments combined with conventional occupational and physical therapy still remain the most promising approach in rehabilitating SCI patients. In this review, advantages and limitations of different FES systems that are used to restore grasping and walking functions are discussed. 相似文献
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Association between blood pressure level and the risk of myocardial infarction, stroke, and total mortality: the cardiovascular health study 总被引:22,自引:0,他引:22
Psaty BM Furberg CD Kuller LH Cushman M Savage PJ Levine D O'Leary DH Bryan RN Anderson M Lumley T 《Archives of internal medicine》2001,161(9):1183-1192
BACKGROUND: Recent reports have drawn attention to the importance of pulse pressure as a predictor of cardiovascular events. Pulse pressure is used neither by clinicians nor by guidelines to define treatable levels of blood pressure. METHODS: In the Cardiovascular Health Study, 5888 adults 65 years and older were recruited from 4 US centers. At baseline in 1989-1990, participants underwent an extensive examination, and all subsequent cardiovascular events were ascertained and classified. RESULTS: At baseline, 1961 men and 2941 women were at risk for an incident myocardial infarction or stroke. During follow-up that averaged 6.7 years, 572 subjects had a coronary event, 385 had a stroke, and 896 died. After adjustment for potential confounders, systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure were directly associated with the risk of incident myocardial infarction and stroke. Only SBP was associated with total mortality. Importantly, SBP was a better predictor of cardiovascular events than DBP or pulse pressure. In the adjusted model for myocardial infarction, a 1-SD change in SBP, DBP, and pulse pressure was associated with hazard ratios (95% confidence intervals) of 1.24 (1.15-1.35), 1.13 (1.04-1.22), and 1.21 (1.12-1.31), respectively; and adding pulse pressure or DBP to the model did not improve the fit. For stroke, the hazard ratios (95% confidence intervals) were 1.34 (1.21-1.47) with SBP, 1.29 (1.17-1.42) with DBP, and 1.21 (1.10-1.34) with pulse pressure. The association between blood pressure level and cardiovascular disease risk was generally linear; specifically, there was no evidence of a J-shaped relationship. In those with treated hypertension, the hazard ratios for the association of SBP with the risks for myocardial infarction and stroke were less pronounced than in those without treated hypertension. CONCLUSION: In this population-based study of older adults, although all measures of blood pressure were strongly and directly related to the risk of coronary and cerebrovascular events, SBP was the best single predictor of cardiovascular events. 相似文献
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The meta-analysis of the Emerging Risk Factor Collaboration demonstrated that the hazard ratios (HR) of the major cholesterol markers and the major apolipoproteins for vascular disease did not differ significantly in the studies they examined. Their conclusion was that they were functionally interchangeable. We believe there are important limitations in the execution of this study. Nevertheless, even if their findings are correct for groups, their conclusions do not follow for individuals. Conventionally, the HR expresses the increase in risk per standard deviation change for that parameter in a group. However, the predicted risk of vascular disease from an atherogenic parameter depends on its concentration within the individual. Depending on the composition of the apoB lipoproteins, individuals may have either concordant or discordant levels of cholesterol and apoB. For those who are concordant, the two markers predict equal risk. For those who are discordant, the predicted risks for the individual are different. We demonstrate that substantial discordance in the individual HR of non-high-density lipoprotein cholesterol and apoB is common. The result is that even with identical overall HR, apoB points to higher risk in a substantial number of individuals whereas the converse is the case for non- high-density lipoprotein cholesterol. Because we are concerned with risks in individuals, not groups, this discordance is important to appreciate and analyze. Our objective should be to learn how to combine the information from parameters rather than eliminate them and we need to focus on evaluation of risk in individuals and not just groups. 相似文献