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Background  Stress gated myocardial perfusion single photon emission computed tomography (gSPECT) is increasingly used before and after intercurrent therapeutic intervention and is the basis for ongoing evaluation in the Department of Veterans Affairs clinical outcomes utilizing revascularization and aggressive drug evaluation (COURAGE) trial. Methods and Results  The COURAGE trial is a North American multicenter randomized clinical trial that enrolled 2287 patients to aggressive medical therapy vs percutaneous coronary intervention plus aggressive medical therapy. Three COURAGE nuclear substudies have been designed. The goals of substudy 0 are to examine the diagnostic accuracy of the extent and severity of inducible ischemia at baseline in COURAGE patients compared with patient symptoms and quantitative coronary angiography and to explore the relationship between inducible ischemia and the benefit from revascularization when added to medical therapy. Substudy 1 will correlate the extent and severity of provocative ischemia with the frequency, quality, and instability of recurrent symptoms in postcatheterization patients. Substudy 2 (n _ 300) will examine the usefulness of sequential gSPECT monitoring 6 to 18 months after therapeutic intervention. Together, these nuclear substudies will evaluate the role of gSPECT to determine the effectiveness of aggressive risk-factor modifications, lifestyle interventions, and anti-ischemic medical therapies with or without revascularization in reducing patients’ ischemic burdens. Conclusions  The unfolding of evidence on the application of gSPECT in trials such as COURAGE defines a new era for nuclear cardiology. We hope the evidence that emerges from the COURAGE trial will further establish the role of nuclear imaging in the evidence-based management of patients with stable coronary disease. The COURAGE trial was supported by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research and Development in collaboration with the Canadian Institutes of Health Research. Unrestricted research grants were obtained from Merck & Co; Pfizer Pharmaceuticals; Bristol-Myers Squibb Medical Imaging; Astellas Pharma; Kos Pharmaceuticals; Data Scope; Astra Zeneca Pharmaceuticals; Astra-Zeneca-Canada; Schering-Plough Coorporation, Ltd; Sanofi-Aventis, Inc; First Horizon; and GE Healthcare. All industrial funding for this trial was directed through the Department of Veterans Affairs. Additional funding for this substudy was provided by grants to the Department of Veterans Affairs and Canadian Institutes of Health Research from Astellas Pharma and Bristol-Myers-Squibb Medical Imaging.  相似文献   
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Factors influencing women to undergo screening mammography   总被引:2,自引:0,他引:2  
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BACKGROUND: Prepulse inhibition (PPI) is an operational measure of sensorimotor gating and is impaired in a family of neuropsychiatric disorders characterized by abnormalities of inhibitory function. Adults with autistic disorder (AD) exhibit clinical features of inhibitory deficits, such as restrictive and repetitive behaviors, that may be explained by deficits in sensorimotor gating. METHODS: Acoustic startle reactivity, habituation, and PPI (30-, 60-, 120-msec interstimulus intervals) were assessed in 14 adult men diagnosed with AD and 16 typically developing normal comparison (NC) participants. All participants were administered measures of intelligence and frontal-executive functioning. RESULTS: Adults with AD exhibited significantly less PPI in the 60-msec condition than NC participants, which was correlated with increased ratings of restricted and repetitive behaviors. The groups did not differ on measures of startle amplitude or overall habituation. There was, however, a significant group-by-block habituation effect. Furthermore, PPI was not related to intelligence but was moderately associated with performance on a measure of frontal-executive functioning. CONCLUSIONS: Adults with AD have sensorimotor gating deficits similar to other neurodevelopmental disorders, implicating a failure of normal inhibitory regulation of sensory, motor, and attentional mechanisms. Thus, PPI deficits may be indirectly linked to one of the hallmark features of AD.  相似文献   
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STUDY OBJECTIVE--The aims were (1) to assess whether termination of pregnancy after prenatal screening by ultrasound affected the prevalence of congenital anomalies at birth, and (2) to examine the trend of this pattern over time. DESIGN--This study deals with congenital anomalies, possibly detectable prenatally or at birth, which were classified as isolated and multiple anomalies; chromosomal anomalies were not included. The prevalence rates of congenital anomalies at birth were determined from case registration data in the Marseille district, France, from the registry of congenital malformations (Eurocat no 22), which covers 23,500 births a year. The chi 2 test for homogeneity in proportions was used to test whether the differences in the total prevalence rates were significant over time. SETTING--The population was defined as all children born to parents living in the Marseille district between January 1 1984 and December 31 1990. PATIENTS--Among the 164,509 pregnancy outcomes monitored during the study, 1795 children with a single congenital anomaly and 288 with multiple congenital anomalies detectable at birth were assessed. MEASUREMENTS AND MAIN RESULTS--The percentage of pregnancy terminations was higher in the case of multiple anomalies (16%) than with single ones (7.5%). Leaving aside the lethal birth defects, this percentage became 7.9% in the case of multiple anomalies and 4.3% with isolated ones. A significant increase (p < 0.001) occurred over the seven year study period in the total percentage of terminations because of isolated anomalies but not in that involving multiple ones. The increase observed in the former case was found to be mainly attributable to an increase in the number of terminations of pregnancy undertaken because of anomalies which were either lethal or associated with very low survival rates (p < 0.001). CONCLUSIONS--Termination of pregnancy after prenatal ultrasound examination was found to have a definite impact on the prevalence at birth of lethal and congenital anomalies with a low survival rate, and this impact tended to increase over time. No such impact was observed in the case of congenital anomalies associated with high survival rates.  相似文献   
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Hypertrophic cardiomyopathy in the dog.   总被引:4,自引:0,他引:4       下载免费PDF全文
Clinical and necropsy findings in 10 dogs with a spontaneous primary hypertrophic cardiomyopathy are described. Each dog had marked cardiac hypertrophy, and 8 dogs had disproportionate thickening of the ventricular septum with respect to the left ventricular free wall (compared with dogs with normal hearts or with cardiac hypertrophy due to acquired or congenital heart disease). Septal:free wall thickness ratios in the 10 dogs ranged from 1.1 to 1.5; 6 had ratios greater than or equal to 1.3. However, marked cardiac muscle cell disorganization in the ventricular septum, characteristic of patients with hypertrophic cardiomyopathy, was present in only 2 of the 10 dogs. Death occurred most commonly while the dogs were under anesthesia during the course of operative procedures (5 dogs) or suddenly and unexpectedly in animals without previous symptomatic manifestations of cardiac disease (3 dogs). Four dogs had clinical signs of congestive heart failure, including 2 with marked cardiac decompensation. In addition, 2 of these 4 dogs with heart failure and 1 dog without previous symptoms (that died during a noncardiac operation) manifested complete heart block. It is conceivable that dogs with spontaneous hypertrophic cardiomyopathy may prove useful in the future investigations of the clinical, hemodynamic, and pathologic features of this disease in humans.  相似文献   
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