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Heart failure represents a significant burden for patients and the Canadian health care system. Home telemonitoring is proposed as an intervention that can improve heart failure outcomes by identifying opportunities for earlier clinical intervention and by providing patients with self-management support between scheduled clinic visits. The objective of this review is to provide clarity with respect to the most recent evidence of the effect of home telemonitoring on heart failure outcomes. Despite some strong evidence that telemonitoring can reduce the risk of mortality and heart failure-related hospitalizations, important inconsistencies exist in the evidence. This article proposes that much of the inconsistency results from differences in the patient population being studied, the type of home telemonitoring intervention, and the implementation setting. Also important is the degree to which intervention fidelity is maintained throughout the course of a study; this is emphasized through a review of the factors that influence the degree to which patients and health care providers use home telemonitoring interventions as intended. In this article we propose that for researchers to produce definitive answers regarding the effect of home telemonitoring on heart failure outcomes, interventions and studies need to be designed and tailored according to the characteristics of the target patient population and the implementation context. 相似文献
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Randolph D. Cohen Jack G. Mottley James G. Miller Peter B. Kurnik Burton E. Sobel 《The American journal of cardiology》1982,50(4):838-843
Quantitative analysis of ultrasound offers a potentially valuable method for noninvasive differentiation of specific types of cardiac disease and for assessment of their severity. Clinical application necessitates quantitative measurement of the ultrasonic properties of myocardium through the chest wall. This study was designed to determine whether such measurements could be made noninvasively with the aid of conventional M mode echocardiographic guidance and to characterize the quantitative effects of intervening tissue (chest wall) on the ultrasonic signals backscattered by ischemic and normal myocardium. Frequency-dependent ultrasonic backscatter (2 to 7 MHz) from normal myocardium was measured in dogs in vivo through the closed chest with the use of M mode guidance and with the chest open, directly from the myocardium. Closed-chest and open-chest measurements were repeated after ligation of the left anterior descending coronary artery in the same animals. Closed-chest data were compensated by correcting for the average value for the slope of the attenuation-frequency function of chest wall, which was determined from measurements obtained by analysis on excised tissue. Compensated closed-chest measurements correlated with measurements obtained from the epicardial surface of the heart. The differentiation of normal from ischemic myocardium with both the closed- and open-chest measurements was consistent (p < 0.005). The successful differentiation of normal from ischemic myocardium by determination of quantitative backscatter through the intervening chest wall supports the concept that tissue characterization by quantitative analysis of backscattered ultrasound is a potentially useful, clinically applicable approach to noninvasive detection and differentiation of intrinsic properties of normal and diseased myocardium. 相似文献
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M Lange J S Salaki J R Middleton P Sen R Kapila M Gocke D B Louria 《American heart journal》1978,96(2):144-152
The total number of cases of heroin-induced endocarditis occurring over a four-year period were reviewed in order to explain an increase in the number of cases in the last year studied (1975). Brown heroin was noted to be used more frequently by addicts during the period of increased incidence. Cultures of "street samples" of brown and white heroin as well as cocaine were obtained in order to elucidate a possible relationship between the increased use of brown heroin and the increased number of endocarditis cases. Despite frequent contamination of both white and brown heroin, none of the common endocarditis-causing pathogens were isolated from the samples. Staphylococcus aureus, the most common etiological agent, frequently resulted in tricuspid endocarditis. That the accepted criteria for tricuspid endocarditis may be present without actual cardiac valve involvement is demonstrated by a most unusual case of hepatic vasculature infection. 相似文献
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F Herreman A Ameur F de Vernejoul J H Bourgin P Gueret F Guerin M Degeorges 《American heart journal》1979,98(1):63-72
Hemodynamic and angiocardiographic analysis was performed prior to and 14 months on the average following valve replacement in 11 patients with severe, isolated, pure, chronic aortic regurgitation.The aortic diastolic pressure, reduced prior to surgery, reverted to normal as did the cardiac index. Left ventricular filling pressure, elevated prior to surgery, returned to normal while aortic systolic pressure did not vary substantially. The markedly increased stroke volume returned to normal as did the net left ventricular stroke work. Left ventricular end-diastolic and end-systolic volumes, also markedly elevated, decreased but did not return to normal levels.The shape of the left ventricle, which was more spherical than normal during end-systole prior to surgery, as evidenced by the decrease in the systolic axis ratio, reverted to normal.The ejection fraction, severely reduced before surgery, increased moderately (46 ± 13 vs 51 ± 19 per cent) as did the extent of circumferential fiber shortening (δD) (21 ± 8 vs 27 ± 12 per cent). The mean velocity of fiber shortening () increased significantly (0.68 ± 0.2 vs 1.03 ± 0.47 circ./sec.), as did the mean left ventricular ejection rate (1.32 ± 0.48 vs 1.91 ± 0.76).Comparative analysis of the evolution of left ventricular function indices and of extramyocardial factors (end-diastolic fiber stretching and impedance to ejection) showed that whereas in some cases myocardial damage appeared to be irreversible, in others dramatic improvement sometimes occurred following surgery. It was not possible, however, to determine the threshold below which the damage was irreversible.It may therefore be concluded that in some patients with severe regurgitation attended by profound myocardial insufficiency, correction of the valvular defect could produce not only clinical and hemodynamic improvement, but also improvement in myocardial contractile status. 相似文献
99.
Frances M. Sobierajski Graeme M. Purdy Charlotte W. Usselman Rachel J. Skow Marina A. James Radha S. Chari Rshmi Khurana Michael K. Stickland Sandra T. Davidge Maureen Devolin Craig D. Steinback Margie H. Davenport 《The Canadian journal of cardiology》2018,34(4):485-491