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111.
白花丹参化学成分的研究   总被引:30,自引:0,他引:30  
从白花丹参(Salvia miltiorrhiza f.alba)中分离出14个二萜醌类化合物,其中2个为新化合物,由光谱分析推定为1,2,15,16-四氢丹参醌(Ⅰ)和丹参醛(Ⅱ);另一个化合物Ⅲ与R0-090680的结构相同。化合物Ⅰ和Ⅲ对淋巴白血病细胞P388均有较强的抑制作用。  相似文献   
112.
Radioimmunoimaging of fresh canine venous thrombi with a murine monoclonal antibody specific for human and dog fibrin has been reported. Successful imaging of canine deep venous thrombi 1, 3, and 5 days old at the time of antibody injection is reported. Images were positive in all dogs, and the uptake of fibrin-specific antibody was equivalent to that of fresh thrombi.  相似文献   
113.
Management of the postinfarction patient should be directed toward identifying and treating individuals at risk of future coronary morbidity or mortality. The history, physical examination, resting ECG, and chest film, supplemented with ambulatory electrocardiographic monitoring, noninvasive assessment of left ventricular function, graded exercise testing, and sometimes angiography allow stratification of patients into high- and low-risk subgroups. A program of exercise training, risk factor modification, and prophylactic therapy with beta blockers would be warranted in most patients. Use of antiarrhythmic agents may alter prognosis in certain subgroups. Evidence is currently insufficient to warrant routine use of anticoagulant or antiplatelet agents in the postinfarction patient.  相似文献   
114.
The effect of the oral vasodilator trimazosin on hemodynamics in 16 patients with chronic left ventricular failure was compared with placebo in a double-blind, randomized study. Eight patients received trimazosin 100 to 300 mg, and 8 received placebo. Over the 6-hr period after medication trimazosin caused no significant change in heart rate, stroke work index, or pulmonary vascular resistance, but there were significant reductions in mean arterial pressure (p less than 0.05), mean right atrial pressure (p less than 0.01), mean pulmonary artery pressure (p less than 0.01), mean pulmonary capillary wedge pressure (p less than 0.01), and systemic vascular resistance (p less than 0.01), and significant increases in stroke index (p less than 0.05) and cardiac index (p less than 0.05). None of 8 patients improved after placebo, whereas 5 of 8 patients (63%) had a good or excellent hemodynamic response after trimazosin (p = 0.006). Four of 4 patients who received 300 mg of trimazosin had a good or excellent response. Trimazosin is a long-acting orally effective vasodilator which improves ventricular function in patients with left ventricular failure.  相似文献   
115.
Human blood groups: incidental receptors for viruses and bacteria   总被引:2,自引:0,他引:2  
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116.
Eighteen patients with hypertension participated in a double-blind, randomized study to evaluate the effect of trimazosin, methyldopa, and placebo on supine and standing blood pressure and heart rate. Of 6 patients on methyldopa, one developed drug fever (and was dropped from the study) and one developed impotence. None of 6 patients on trimazosin and none of 6 patients on placebo developed any adverse effects. The mean supine blood pressure on 900 mg trimazosin daily was 17.0/12.8 mm Hg lower than that on the first placebo trial (p less than 0.01) and 17.0/12.1 mm Hg lower than that on the second placebo trial (p less than 0.01). The mean supine blood pressure on 2,250 mg methyldopa daily was 17.8/12.4 mm Hg lower than that on the first placebo trial (p less than 0.01) and 16.8/13.0 mm Hg lower than that on the second placebo trial (p less than 0.01). The mean supine blood pressure was not significantly affected by placebo. Trimazosin, 900 mg daily, and methyldopa, 2,250 mg daily, were equally effective in lowering supine and standing systolic and diastolic blood pressure and did not affect supine or standing heart rate.  相似文献   
117.
Macrophages from rabbit peritoneal exudate cells incubated in vitro with T2 bacteriophage from 10 up to 120 minutes show phage particles adsorbed to cell membranes, in the process of being engulfed by means of rhopheocytosis, micropinocytosis, and phagocytosis, and localized within dense vacuoles, semi-dense vacuoles, and clear vacuoles of the cytoplasm. The electronmicrographs suggest that newly formed endocytic vacuoles containing phage particles fuse with one another and also fuse with dense bodies of the cytoplasm as they migrate towards the cell interior, thus yielding larger vacuoles of varying densities containing higher concentrations of phage. The polymorphonuclear cells present in a small proportion in the peritoneal exudate cells also endocytosed phage particles. The T2 particles are found in large cytoplasmic vacuoles surrounded by an electron-opaque material presumably derived from cytoplasmic granules. No disintegration of T2 phage within the macrophage following incubations up to 120 minutes could be demonstrated; however, disrupted phage particles were noted within cytoplasmic vacuoles of polymorphonuclear leucocytes after 15 minutes' incubation.  相似文献   
118.
Usefulness of the resting electrocardiogram in the elderly.   总被引:1,自引:0,他引:1  
The ECG is useful in diagnosing acute myocardial infarction and unrecognized Q-wave myocardial infarction in the elderly. Unrecognized myocardial infarction and myocardial infarction associated with clinical symptoms have a similar incidence of new coronary events. Ischemic ST-segment depression on the resting ECG is associated with an increased incidence of new coronary events. The ECG is useful in the diagnosis of LV hypertrophy but is less sensitive and less specific than echocardiography in diagnosing LV hypertrophy. ECG LV hypertrophy is associated with an increased incidence of cardiovascular events in the elderly. However, echocardiographic LV hypertrophy is more sensitive in predicting new coronary events, atherothrombotic brain infarction, and congestive heart failure than is ECG LV hypertrophy. The ECG is also useful in diagnosing conduction defects and arrhythmias in the elderly. In the elderly, left bundle branch block, intraventricular conduction defect, Type II second-degree atrioventricular block, and pacer rhythm are associated with an increased incidence of new cardiac events, whereas right bundle branch block, left anterior fascicular block, and first-degree atrioventricular block are not. In the elderly, atrial fibrillation is associated with an increased incidence of thromboembolic stroke and new cardiac events. Premature atrial complexes and paroxysmal supraventricular tachycardia are not associated with an increased cardiac risk. Complex ventricular arrhythmias on the resting ECG are associated with an increased incidence of cardiac events in elderly patients with heart disease but not in elderly patients without heart disease.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
119.
120.
Objective: To pilot an intervention to prevent functional decline and health problems among persons with intellectual and developmental disability aging in the community. Design: Pilot for a large randomized trial. Setting: Private residences and group homes. Participants: 201 adults with intellectual and developmental disability, aged 32 years and older, were randomly assigned to an advance practice nurse (APN) intervention (n=101) or health-risk appraisal and feedback only (HRA) intervention (n=100). Interventions: The APN group received in-home multidimensional assessment, targeted recommendations, and quarterly follow-up visits for up to 1 year. The HRA group received an in-home interview with written feedback. Main Outcome Measures: Health, functional status, and risks; use of acute medical services; and feasibility assessment. Results: Assessment tools and interventions were demonstrated to be feasible in a population with mild to moderate intellectual and developmental disability. Recruitment and randomization were successful (avg age, 41y; 52% men). High levels of health risks were identified (mean, 7.6; range, 1-20y); 23.4% reported “fair” or “poor” general health; 16.4% reported probable depression; 34.5% reported recent falls; 36.8% reported fair or poor oral health; and 32.7% reported pain moderate or worse. Conclusion: Interventions are feasible for trials in this population and have broad applicability to other populations aging with disability.  相似文献   
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