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941.
Richard Spoth Charles Meade 《Journal of behavior therapy and experimental psychiatry》1981,12(1):57-61
This exploratory study investigated the effectiveness of cue-controlled relaxation in the multiple-outcome reduction of general anxiety. Additionally, it examined the effects of matching the technique's presentation with trainee conceptual level. Results suggested that the technique significantly reduced general anxiety. Multivariate analysis of covariance also indicated that the training was differentially effective relative to trainee conceptual level, but not relative to the type of technique presentation. 相似文献
942.
Risk factors for stroke and myocardial infarction in women in the United Kingdom as assessed in general practice: a case-control study 总被引:1,自引:0,他引:1
Data available in the United Kingdom through the Medical Research Council's General Practice Research Framework were recorded in a study of 603 women aged 45-69 with confirmed diagnoses of stroke or myocardial infarction, each matched by age with two controls. Current cigarette smoking and a family history of myocardial infarction were both strongly associated with the risk of stroke and myocardial infarction, with relative risks of 2.47 (95% confidence interval 1.89 to 3.23) and 1.93 (95% confidence interval 1.52 to 2.44) respectively. The relative risks associated with past smoking decreased according to the length of time since stopping smoking. A family history of stroke was not significantly related to the risk of stroke or myocardial infarction. Single women had a lower risk of stroke and myocardial infarction than married women (relative risk 0.49), but parity, past use of oral contraceptives, and menopausal state were not significantly related to the risk of stroke and myocardial infarction in this study. Other characteristics that were identified as risk factors either for subsequent stroke or for myocardial infarction included not only hypertension, diabetes, and past histories of stroke and myocardial infarction, but also past histories of gynaecological cancer and of venous thrombosis. The association with venous thrombosis may indicate the importance of the haemostatic system in a common pathogenesis of venous thrombosis and myocardial infarction. 相似文献
943.
Osteoblastoma is an uncommon primary bone tumor that rarely is found in the hand or wrist. Recurrent osteoblastomas often have a more aggressive appearance than the original tumor, and differential diagnosis from osteosarcoma is difficult. The pain that can accompany this tumor is debilitating. Therefore, successful treatment requires complete removal of the tumor. The purpose of this report is to present an unusual case of osteoblastoma of the carpal scaphoid. This tumor was treated successfully by curettage and bone grafting. At 1 year postoperatively, the patient presented with a stable, painless wrist with full range of motion. 相似文献
944.
945.
Comparison of methods for renogram evaluation 总被引:1,自引:0,他引:1
946.
Hypoxanthine-guanine phosphoribosyltransferase: characteristics of the mutant enzyme in erythrocytes from patients with the Lesch-Nyhan syndrome 总被引:9,自引:3,他引:6
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William J. Arnold Jean C. Meade William N. Kelley 《The Journal of clinical investigation》1972,51(7):1805-1812
The Lesch-Nyhan syndrome is characterized clinically by choreoathetosis, spasticity, selfmutilation, and mental and growth retardation. Biochemically, there is a striking reduction of hypoxanthine-guanine phosphoribosyltransferase (HGPRT) activity in affected individuals. We have examined erythrocytes from 14 patients with the Lesch-Nyhan syndrome for the presence of hypoxanthine-guanine phosphoribosyltransferase activity and enzyme protein. In contrast to the usual finding of no detectable hypoxanthine-guanine phosphoribosyltransferase activity, we have found low levels (0.002-0.79 nmoles/mg protein per hr) of hypoxanthine-guanine phosphoribosyltransferase activity in erythrocyte lysates from five of these patients. In three of the five patients, hypoxanthine-guanine phosphoribosyltransferase activity appeared to be substantially more labile in vivo than normal using erythrocytes which had been separated according to their density (age).Immunochemical studies using a monospecific antiserum prepared from a homogeneous preparation of normal human erythrocyte hypoxanthine-guanine phosphoribosyltransferase revealed immunoreactive protein (CRM) in hemolysate from all 14 patients with the Lesch-Nyhan syndrome. The immunoreactive protein from each patient gave a reaction of complete identity with normal erythrocyte hypoxanthine-guanine phosphoribosyltransferase and was present in quantities equal to those observed in normal erythrocytes. In addition, a constant amount of CRM was found in erythrocytes of increasing density (age) from patients with the Lesch-Nyhan syndrome despite the decreasing hypoxanthine-guanine phosphoribosyltransferase activity.These studies confirm previous data which indicate that the mutations leading to the Lesch-Nyhan syndrome are usually, if not always on the structural gene coding for hypoxanthine-guanine phosphoribosyltransferase. In addition, although the mutant proteins appear to be present in normal amounts, they are often very labile in vivo with respect to enzymatic activity. These observations suggest that therapy directed at stabilization or activation of enzyme activity in vivo may be of potential benefit. 相似文献
947.
948.
Partition of thallium-201 in isolated myocardial tissue of rats previously injected at rest or after exercise 总被引:1,自引:0,他引:1
The kinetics and distribution of TI-201 in isolated myocardial tissue of rats injected i.v. with this radionuclide are compared at rest and after exercise (2 hr of forced swimming). At 1/2 and 3 hr after injection, a myocardial segment was obtained and subjected to continuous washout with the radioactivity remaining in the tissue recorded each 10 sec for 1 hr. Altogether there were four groups of ten animals each. A three-compartment model (extracellular, main intracellular, and subcellular) was found to describe adequately the kinetics of TI-201. In the groups studied 1/2 hr after TI-201 injection the most dramatic effect of exercise was a translocation of TI-201 into the subcellular compartment. The change was also present but less marked in samples from exercised rats obtained 3 hr after TI-201 injection, which suggests a transition to the resting stage. The findings suggest the possibility of structural subcellular differences in myocardial uptake for TI-201 in clinical images visualized after exercise and at rest. 相似文献
949.