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51.
A 44‐year‐old man with structurally normal heart underwent catheter ablation of left ventricular summit tachycardia. The initial mapping revealed the origin of tachycardia at the junction of great cardiac vein and anterior interventricular vein. During ablation the exit site shifted to the nearby regions, which was recognized by subtle changes of 12‐lead ECG. Mapping and ablating at different exit sites rendered the tachycardia noninducible.  相似文献   
52.
A 41-year-old man presented with Cushing's syndrome and the biochemical features of ectopic ACTH production. Investigation revealed mediastinal metastases from a medullary carcinoma of the thyroid. The peripheral plasma contained grossly elevated levels of bombesin-like immunoreactivity (irBombesin) as well as calcitonin; blood sampling via a venous catheter confirmed a gradient of irBombesin, but not of ACTH, in the mediastinal vein draining the tumour. On extraction the tumour contained a bombesin-like peptide, but not vasopressin or corticotrophin releasing factor and only very low levels of ACTH; immunohistochemical studies showed positive immunostaining for bombesin and calcitonin but none for ACTH or CRF. No ACTH was released from dispersed tumour cells in vitro. However an extract of the tumour stimulated ACTH release in vitro from perifused dispersed rat anterior pituitary cells. This is the first reported case of Cushing's syndrome due to ectopic production of a bombesin-like peptide, causing excessive pituitary ACTH secretion.  相似文献   
53.
Murine, polyclonal and monoclonal antibodies, raised against sporozoites of Eimeria tenella, were tested for their ability to neutralize sporozoite infectivity in vitro and in vivo. Neutralization was effected via three mechanisms. Firstly, sporozoites fixed complement, at low titres, and lysis occurred by the alternative pathway of complement activation. Secondly, in the absence of complement activity, the murine heat-inactivated, hyperimmune antiserum neutralized sporozoites at relatively low titres. At high titres, even though sporozoites were agglutinated, neither the heat-inactivated hyperimmune antiserum nor the monoclonal antibody neutralized sporozoites. Finally, in the presence of complement and specific antibodies, at titres which by themselves would not neutralize sporozoites, neutralization was effected due to lysis via the classical pathway of complement activation.  相似文献   
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Electromechanical Interval and Strokes After Ablations of AF . Introduction: Atrial fibrillation (AF) is associated with increased risk of embolic stroke. Catheter ablation of AF provides an effective therapy for patients with symptomatic and drug‐refractory AF. The aim of this study was to evaluate whether the atrial electromechanical interval is useful in identifying patients at risk of stroke after successful catheter ablation. Methods and Results: A total of 279 AF patients who received catheter ablation and showed no evidence of recurrences were enrolled. Electromechanical interval (PA–PDI) was determined as the time interval from the initiation of P wave deflection to the peak of mitral inflow A wave on pulse wave Doppler imaging. The PA–PDI interval was measured for each patient after the 3‐month blanking period of catheter ablation. The clinical endpoint was the occurrence of ischemic stroke. During the follow‐up of 46.5 ± 17.2 months, 6 patients suffered from ischemic strokes. Patients with strokes had higher CHA2DS2–VASc scores and longer PA–PDI intervals (138.7 ± 12.4 ms vs 161.2 ± 7.7 ms, P value < 0.001) compared to those without strokes. At a cutoff point of 150 ms identified by ROC curve, the positive and negative predictive values of the PA–PDI interval to predict stroke were 86.7% and 100%, respectively. The PA–PDI interval improved the predictive performance of the CHA2DS2–VASc score, and the area under the ROC curve increased from 0.75 to 0.85. Conclusions: Our results suggest that the PA–PDI interval is a useful tool to identify patients with high risk of stroke after successful catheter ablation of AF. (J Cardiovasc Electrophysiol, Vol. 24, pp. 375‐380, April 2013)  相似文献   
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A retrospective analysis of 80 cases of gonococcal ophthalmia revealed six (7.5%) to be due to penicillinase-producing Neisseria gonorrhoeae (PPNG), five neonatal cases and one adult. All six cases were finally cured, but best results were obtained with topical chloramphenicol and single-dose spectinomycin (40 mg/kg) given intramuscularly. All gonococcal isolates should be tested promptly for penicillinase production, and if this is present systemic treatment, modified to spectinomycin or penicillinase-stable cephalosporin, should be given as single-dose treatment.  相似文献   
58.
Objective This study was designed to identify determinants of body size perceptions and their relationship to dietary behavior in a multiethnic group of women.Design A single interview consisting of the Massara and Stunkard body image cards (1979) and questionnaires on sociocultural background, anthropometry, and dieting history were administered to volunteers from the staff of a hospital.Subjects The sample was a convenience sample of 186 women representing a range of staff positions recruited from Methodist Hospital in Brooklyn, NY; 174 completed the study. Data on 150 women are presented in this article.Results Height and weight-for-height were stronger predictors of accuracy of perceived body size than ethnicity. Tall, slight women were more likely to overestimate and short, heavy women were more likely to underestimate actual body size. Ethnicity had an interactive effect with height as taller European Americans were more likely to perceive their body size as larger than actual compared with Afro-Caribbeans and African Americans. Women with a history of dieting were more likely to overestimate their size and to view it as different from what is perceived as attractive to others.Applications/conclusions Based on the results, we conclude that body size is a stronger predictor of accuracy of perceived body size than ethnicity; and dieters overestimate their body size and believe it to be heavier than their social group would prefer. J Am Diet Assoc. 1996; 96:252-256.  相似文献   
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Abstract – Visual communicaltion equipments were developed early by radiologists for the transmission of analog signals, whereas today's transmission systems are based on digitization of the radiograph. For teletransmission of dental radiographs, it is essential to assess the diagnostic accuracy of various spatial and gray-scale resolutions. Each of 83 dry mandibles was divided into four regions. By random assignment it was decided for each region whether or not a hole should be drilled. Intraoral radiographs (3 × 4 cm) were performed of each region and interpreted. The radiographs were thereafter recorded by a video camera connected to an IBM-PC. The personal computer held a hardware digitization card defmed at a 512 × 512 spatial resolution with the possibility of selecting varying gray-scale resolutions. All radiographs were assessed in resolutions with 256 (8 bit), 128 (7 bit), 64 (6 bit), and 32 (5 bit) shades of gray. In no case was the original radiograph more accurate than the 512 × 512 × 8 resolution. In two of the regions evaluated, the images providing 32 shades of gray were less accurate (percentage of true positives and negatives) thao the other resolutions ( P <0.05) while in one region resolutions of 8 bit depth (256 shades of gray) provided a significantly greater accuracy than did the original radiograph and the other image resolutions ( P <0.05). This was due to fewer false negative scores and was not followed by an increase in false positive scores. It can be concluded thai a 512 × 512 spatial resolution is satisfactory for the detection of bone lesions in digitized intraoral radiographs and that 64 shades of gray provide an equally good diagnostic accuracy as do the original radiograph. This might be relevant when transmission times are of importance.  相似文献   
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