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991.
992.
Real-time interactive color flow magnetic resonance (MR) imaging is a combination of real-time MR imaging and color encoding of velocity-induced phase angle. Flow-compensated (FC) and flow-encoded (FE) images are acquired continuously by using gradient echoes and a 12-msec repetition time. Each image is reconstructed within 200 msec of acquisition, and the FC magnitude image is displayed in gray-scale format. The phase difference between the reconstructed FC and FE images, a difference proportional to velocity along the flow-encoding direction, is encoded in color and superimposed on the gray-scale FC image. Magnitude and phase information are thus presented simultaneously. The viewer may interactively adjust many acquisition parameters during data acquisition. Experimental results of phantom and in vivo human studies validate the method. Characteristics of the color flow MR imaging technique are compared with those of duplex color ultrasound.  相似文献   
993.
Two elderly patients had pain after hip trauma with no radiographic evidence of fracture. Computed tomography demonstrated capsular haematoma. Scintimetry revealed femoral head ischaemia. Intracapsular hip joint pressure in extension was 240 and 176 mm Hg, respectively, in neutral position and 280 and 360 mm Hg in internal rotation. The hip joints were aspirated for 8 ml and 5 ml of blood, respectively, leading to pain relief and regained radiotracer uptake in the femoral head. It is concluded that traumatic hip joint tamponade may cause femoral head ischaemia which may be reversed by aspiration.  相似文献   
994.
Changes in primary and secondary process functioning as well as in experienced locus of control as indicators of cognitive style were examined as a function of alcohol intoxication. Women subjects drank 1.0 ml of pure alcohol/kg body weight and were compared to a placebo and a control group. Results indicated a significant shift in locus of control toward greater externality and a significant shift in cognitive style from a dominance of secondary process when sober to a dominance of primary process when intoxicated. These shifts were discussed as indicative of the pharmacological properties of alcohol and were related to the disinhibition and the arousal hypotheses. Alternative explanations were also discussed.  相似文献   
995.
The expression of five antigens, associated with transitional cell carcinoma (TCC) of the urinary bladder on biopsies of tumors or normal urothelium, was studied by immunostaining with the corresponding monoclonal antibodies. Both tissue sections and single cell preparations were investigated with either indirect immunoperoxidase staining or immunofluorescence. All 5 antigens were expressed on the majority (70-90%) of sectioned tumor specimens from 44 TCC patients, and 4 of them were similarly expressed on single cell tumor preparations from 26 additional patients. However, in both types of preparation, the degree of expression of these antigens varied from scattered staining of less than 25% of the tumor cells to homogenous staining of all or almost all cells. This degree of expression varied individually for each of the antigens and was not related to the malignancy grade of the tumors. However, as most of the tumors were of grades II or III, no conclusions regarding the relationship of antigen expression to the aggressiveness of the tumors can be drawn. In any event, all tumors expressed at least one and mostly several of these antigens. Antigen expression on biopsies of normal bladder mucosa from TCC patients or on urothelial biopsies from patients with prostate hyperplasia was also observed on single cell specimens (34 patients) but not on sectioned material (9 patients). However, the frequency of positive specimens was much lower (4-20%). Moreover, the number of cells expressing one or, occasionally, several of the antigens in normal urothelium was small (usually less than 5%). Because of these marked differences in antigen expression between tumors and normal tissue, the results indicate that a combination of 3-5 of the antibodies used in this study may be suitable for diagnostic purposes.  相似文献   
996.
997.
998.
The impact of the cancer diagnosis and its effects on the lives of patients and family members can put a serious strain on intra-family relationships. This paper describes how to initiate, lead and analyze supportive group therapy meetings for families of individuals with cancer based on our experiences in conducting more than 600 group sessions over the last 12 years. We have found that most families can benefit from multiple-family therapy sessions and that highly-stressed families can benefit significantly from both multiple- and single-family therapy meetings. Discussed is the need for therapists to be alert to non-verbal as well as verbal communications of families and the need for different interacting techniques for each type of therapy group. The meetings aim to overcome family members' resistance to discussing the emotional distress caused by the disease and to encourage them to bring into the open conflicts from the past, anxieties about the present, and fantasies regarding the future.  相似文献   
999.
To assess myocardial glucose metabolism and perfusion in 142 myocardial segments with defects seen at thallium-201 single photon emission computed tomography (SPECT), 27 studies with positron emission tomography (PET) utilizing nitrogen-13 ammonia and fluorine-18 deoxyglucose were performed in 26 patients. Myocardial infarction was defined on the basis of concordant reductions in segmental perfusion and glucose utilization; myocardial ischemia, on the basis of preservation of glucose utilization (metabolic viability) in segments with hypoperfusion at rest. Of the 142 segments analyzed, 101 had fixed defects, 31 had partially reversible defects, and ten had completely reversible defects. Preserved glucose utilization was identified in 47 (46.5%) of the segments with fixed defects and 20 (64.5%) of the segments with partially reversible defects. Of the ten segments with completely reversible defects, five (50%) were normal, and five (50%) exhibited ischemia at PET. Visual improvement in a persistent thallium defect at delayed imaging was not associated with residual glucose metabolic activity. Thus, PET can be used to detect glucose metabolic activity in a significant proportion of myocardial segments with fixed or partially redistributing defects seen at thallium SPECT, which suggests that the extent of tissue viability in patients with ischemic heart disease is underestimated at thallium scintigraphy.  相似文献   
1000.
Extracorporeal shock wave lithotripsy (ESWL), either alone or in combination with percutaneous or retrograde techniques, has rapidly become the procedure of choice for the treatment of intrarenal and upper ureteral calculi. Complications have been few so far and usually have been urinary obstructions or hemorrhages. Most fluid collections observed after ESWL are asymptomatic and their detection usually does not prolong hospitalization or alter therapy. In five patients out of 2,149 patient treatments symptomatic renal hematomas developed within a few hours after ESWL for renal calculi. In two of these patients the partial thromboplastin time was mildly prolonged. In four patients blood volume replacement was required to treat a falling hematocrit reading or hypotension. Diagnosis of the hematomas was initially made with sonography, although computed tomography and magnetic resonance imaging were used to further define the distribution and extent of retroperitoneal hematomas. Severe ipsilateral flank pain and rapid decrease in the hematocrit reading after ESWL strongly suggest significant bleeding from the treated kidney and require prompt radiologic confirmation and careful clinical treatment until there is evidence that the hemorrhage has stopped.  相似文献   
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