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41.
OBJECTIVE: To examine the reliability and validity of the proposed American College of Rheumatology (ACR) neuropsychological battery for patients with systemic lupus erythematosus (SLE). METHODS: Thirty-one SLE patients with a history of neuropsychiatric symptoms (NPSLE), 22 SLE patients without a history of neuropsychiatric symptoms (non-NPSLE), and 25 healthy controls completed measures of cognition at baseline and after 1 month. The 1-hour proposed ACR-SLE battery was compared with a 4-hour comprehensive battery (CB). RESULTS: Seven of 12 measures from the ACR-SLE battery were lower in SLE patients compared with controls. Overall agreement between impairment on the ACR-SLE battery and the CB was 90%. This was established using previously defined impairment on the CB and 4 of 12 scores impaired on the ACR-SLE battery. Almost perfect agreement between the 2 batteries was found for non-NPSLE patients and healthy controls (95-96%) and moderate agreement was reported for NPSLE patients (81%). Intraclass correlation coefficients for ACR-SLE tests ranged from 0.40 to 0.90, indicating adequate reliability. CONCLUSION: Reliability and validity of the ACR-SLE battery was established in this study. Agreement regarding classification for impairment was almost perfect for non-NPSLE and moderate for the NPSLE patients. The ACR battery is well designed for general classification of cognitive impairment in SLE. However, comprehensive testing may be useful in identifying specific deficits in NPSLE.  相似文献   
42.
The usual methods for preparing lungs for morphologic study involve the instillation of fixatives that modifyproteins and RNA such that the tissue is unsuitable for molecular studies. To develop a technique suitable for molecular studies, pieces of adult rat lungs were infiltrated with agarose, glutaraldehyde, or paraformaldehyde and the consistency of alveolar inflation was compared to lungs inflated with 10% formalin. Only direct injection with 1% agarose resulted in comparable inflation of lung tissue and preserved RNA and protein. Thus, this technique enables simultaneous molecular and morphometric analysis of the lung on small pieces of lung tissue in heterogeneous lung diseases.  相似文献   
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Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients.  相似文献   
45.
Physical activity favorably influences atherosclerosis risk factors but only a few studies in adults considered the time watching television (TV) as a measure of physical inactivity. We therefore determined in a population-based sample of 1778 subjects from the NHLBI Family Heart Study (FHS) whether leisure time physical activity and TV watching have independent or interactive associations with cardiovascular disease risk factors and carotid artery intima-media wall thickness (IMT). Subjects were free from diabetes mellitus and clinically-ascertained coronary artery disease and did not take lipid-lowering or antihypertensive drugs. Only 0.7 and 1.3% of the variance in leisure time physical activity in women and men, respectively, was explained by the amount of TV watching. Leisure time physical activity had a clearly favorable, and TV watching an unfavorable association with anthropometric measurements (BMI (body mass index), waist girth, waist-hip ratio, subscapular and triceps skinfold thickness). The odds ratio (95% CI) of being overweight was 0.41 (0.28-0.62) in women and 0.69 (0.46-1.04) in men in the highest quartile of leisure time physical activity compared to the lowest quartile. The odds ratio increased for increasing quartiles of TV watching to 2.12 (1.45-3.10) in women and 1.61 (1.07-2.43) in men. Watching TV only 1 h per day in women with a BMI of 30 kg/m2 and doing about 75 min of moderate exercise per week was associated with a BMI 1.8 kg/m2 lower than in women watching TV 3 h per day and doing the same amount of exercise. Those with twice the amount of moderate exercise and watching TV 1 h per day had a BMI 0.45 kg/m2 lower. Furthermore, leisure time physical activity was negatively associated with concentrations of triglycerides and positively with HDL cholesterol in both genders. TV watching was significantly positively associated with triglycerides and slightly negatively with HDL cholesterol in men. The observed associations of leisure time physical activity and TV watching with atherosclerosis risk factors were independent from each other. Finally, we analyzed the relation between leisure time physical activity, TV watching and the degree of IMT of the carotid arteries. Neither of these two measures was significantly associated with IMT. In summary, TV watching, in addition to leisure time physical activity, shows an independent association with obesity-related anthropometric measurements, HDL and triglycerides. Decreasing the amount of TV watching might be effective as a first step in reducing atherosclerosis risk factors, especially overweight.  相似文献   
46.
Two hundred forty-one patients (163 male, 78 female) underwent isolated aortic valve replacement at the Medical College of Georgia from 1963 to 1976. The mean age was 46 years (range 12 to 72). Thirty-seven percent had aortic stenosis, 39 percent aortic regurgitation and 24 percent mixed valve lesions. One hundred ninety-eight were in New York Heart Association functional class III or IV. Forty-three were in functional class I or II and underwent surgery for endocarditis, severe regurgitation with rapidly increasing heart size or appearance of angina or electrocardiographic signs of ischemia.  相似文献   
47.
The index Vpm (the actual or physiologic maximal shortening velocity of the contractile element) has been obtained from the analysis of left ventricular pressure recordings and then applied to the assessment of myocardial contractility in man. Pressures during the isovolumic period of ventricular systole were recorded during routine catheterization of 46 patients with a variety of cardiac lesions. The quantity Vpm, that is (dp/dt/kp)max, was compared with the hemodynamic evaluation of each patient based on the left ventricular end-diastolic pressure, ejection fraction and left ventricular end-diastolic volume. Vpm was selected for this study since it appeared to be largely independent of load and does not require biplane angiocardiography and extrapolation analyses.  相似文献   
48.
INTRODUCTION: Ventricular oversensing (OS) of respirophasic noise transients may cause spurious detections and therapies and pacing inhibition among patients with implantable cardioverter defibrillators (ICDs). The incidence of OS and its relationship to clinical variables and ICD system design are unknown. METHODS AND RESULTS: Three hundred twenty-nine patients performed provocative respiratory maneuvers at rest during intrinsic rhythm and continuous ventricular pacing. OS resulting in spurious ventricular detections was provoked in 3 (0.9%) of 329 patients during intrinsic rhythm and 34 (10.3%) of 329 during pacing. Noise transients not recognized and marked as sensed events, but visually evident on the local endocardial ventricular electrogram, were provoked in an additional 23 (7.0%) of 329 patients. Multivariate logistic regression identified history of spontaneous OS (P < 0.0005, odds ratio 9.7, 95% confidence interval [CI] 1.9 to 50.0), automatic gain control device (P < 0.0005, odds ratio 5.3, 95% CI 2.6 to 10.8) or integrated bipolar lead (P = 0.05, odds ratio 2.6, 95% CI 1.0 to 7.25), and male gender (P = 0.008, odds ratio 3.7, 95% CI 1.2 to 11.1) as predictive of provocable OS. Spontaneous OS resulting in spurious ventricular detections and therapies occurred in 12 (3.6%) patients during follow-up. Eleven of 12 spontaneous episodes occurred in male patients during ventricular pacing; 11 of 12 patients had automatic gain control devices and integrated bipolar leads. CONCLUSION: OS is commonly provoked in ICD patients during ventricular pacing and may occur spontaneously, causing spurious tachyarrhythmia therapies and pacing inhibition. Differences in the incidence of spontaneous and provoked OS between ICD systems can be explained on the basis of unique features of automatic sensing systems and sensing lead design.  相似文献   
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50.
Cutaneous skin tags (acrochordons) have recently been proposed as markers for adenomatous polyps of the colon among symptomatic patients referred for colonoscopy. To ascertain the utility of skin tags as a predictor of colonic polyps in a primary care setting, 492 patients, with a mean age of 58 +/- 13.3 years (241 with signs or symptoms and 251 for screening), were evaluated for the presence of skin tags and then examined using a 60-cm fiberoptic sigmoidoscope by an examiner "blinded" to the skin findings. Among patients with skin tags, 23 (10.2%) of 226 had polyps, whereas among patients without skin tags, 20 (7.5%) of 266 had polyps. The predictive value of the presence of a skin tag was 10.2%. Contrary to studies done in more selected populations with a higher prevalence of adenomatous polyps, the results using a 60-cm flexible sigmoidoscope in a primary care population suggest that cutaneous skin tags are not a marker for adenomatous polyps of the colon.  相似文献   
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