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排序方式: 共有598条查询结果,搜索用时 15 毫秒
1.
Peter R. Ellis Victoria J. Burley Anthony R. Leeds David B. Peterson† 《Journal of human nutrition and dietetics》1988,1(2):77-84
We have developed a guar wholemeal bread and tested its physiological efficacy and sensory qualities. The objective of the study was to estimate the optimum concentration of guar in bread required to reduce postprandial glycaemia and insulinaemia without adversely affecting the quality of the bread. Following overnight fasts, 15 normal weight, non-diabetic subjects consumed meals of wholemeal bread alone (controls) and supplemented with guar at three different concentrations (5, 10 and 15% replacement of wheat flour). Blood samples for glucose and insulin analysis were taken preprandially, and at 30 and 60 min after the start of each meal. The acceptability of the wholemeal control and guar breads was assessed using a hedonic scaling method. A significantly lower blood glucose rise at 30 min was found after the 15% guar bread meal compared to the control. Plasma insulin responses at 30 and 60 min were significantly lower after the 10 and 15% guar bread meals compared to the controls. Hedonic scores indicated that the subjects found the 5 and 10% guar breads acceptable and in the case of the 5% variety the mean score was identical to the control. We suggest that a guar concentration of between 5 and 10% replacement of wheat flour (wholemeal or white) should be used for the baking of guar wholemeal bread but further work is needed to define the precise quantity of guar required. 相似文献
2.
Acromegaly is a disease with protean manifestations that are well described in the literature. One finding infrequently encountered is aneurysmal dilatation of the internal carotid arteries and their branches. A case is presented, with CT documentation, in which the enlarged cavernous portions of the internal carotid arteries prolapsed into the sella turcica and enlarged it. Frontal bossing, frontal sinus enlargement, a dense cortical calvarium, prominent inion, and proptosis secondary to extraocular muscular enlargement were findings also present in this patient. The sella CT appearance has brought the term "kissing intrasellar arteries" to mind to suggest the diagnosis. 相似文献
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Lymphangiograms were made in dogs with experimental congestive heart failure by cannulation of the left cardiac efferent (LCE), left pulmonary efferent (LPE), or cardiopulmonary lymphatic and injection of radiopaque medium. The lymphoangiograms showed cardiac enlargement and dilated mediastinal lymphatic channels consistent with an increase in lymph flow. By consecutive injections in the LCE and LPE, wer demonstrated that a common channel, the cardiopulmonary lymphatic, is opacified by injection in either the LPE or LCE. This common channel has been called the "cardiac lymphatic" and used for the collection of "cardiac" lymph. The authors' experiments suggest that this cardiopulmonary lymphatic carries both cardiac and pulmonary lymph. 相似文献
5.
Falx and interhemispheric fissure on axial CT: II. Recognition and differentiation of interhemispheric subarachnoid and subdural hemorrhage 总被引:1,自引:0,他引:1
R D Zimmerman E J Russell E Yurberg N E Leeds 《AJNR. American journal of neuroradiology》1982,3(6):635-642
Interhemispheric hyperdensity or unenhanced computed tomography was originally considered a sign of subarachnoid hemorrhage, the "falx sign." It has since been identified as a normal feature and has also been seen with interhemispheric subdural hemorrhage. To determine the differential features of interhemispheric hemorrhage, 50 patients with subarachnoid hemorrhage and 32 patients with interhemispheric subdural hematomas were reviewed. Subarachnoid hemorrhage produced anterior interhemispheric hyperdensity only, with a zigzag contour and extension from the calvarium to the rostrum of the corpus callosum. Interhemispheric subdural hematomas produce unilateral crescentic hyperdensities that are largest in the posterior superior part of the fissure, behind and above the splenium of the corpus callosum. Interhemispheric hyperdensity in children is more complex. Because the anterior part of the fissure is narrow in younger patients, subarachnoid hemorrhage may go undetected. Likewise, interhemispheric subdural hematomas in children are smaller and more difficult to recognize. They produce asymmetric thickening of the falx shadow with extension over the tentorium. They are, however, of great significance since they are generally seen in abused patients and carry a poor prognosis. 相似文献
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Characterization of benign and metastatic vertebral compression fractures with quantitative diffusion MR imaging 总被引:30,自引:0,他引:30
BACKGROUND AND PURPOSE: Conventional imaging techniques cannot be used to unambiguously and reliably differentiate malignant from benign vertebral compression fractures. Our hypothesis is that these malignant and benign vertebral lesions can be better distinguished on the basis of tissue apparent diffusion coefficients (ADCs). The purpose of this study was to test this hypothesis by using a quantitative diffusion imaging technique. METHODS: Twenty-seven patients with known cancer and suspected metastatic vertebral lesions underwent 1.5-T conventional T1-weighted, T2-weighted, and contrast-enhanced T1-weighted imaging to identify the lesions. Diffusion-weighted images of the areas of interest were acquired by using a fast spin-echo diffusion pulse sequence with b values of 0-250 s/mm(2). The abnormal regions on the diffusion-weighted images were outlined by using the conventional images as guides, and the ADC values were calculated. On the basis of pathologic results and clinical findings, the cases were divided into two categories: benign compression fractures and metastatic lesions. The ADC values for each category were combined and plotted as histograms; this procedure was followed by statistical analysis. RESULTS: The patient group had 12 benign fractures and 15 metastases. The mean ADC values, as obtained from the histograms, were (1.9 +/- 0.3) x 10(-4) mm(2)/s and (3.2 +/- 0.5) x 10(-4) mm(2)/s for metastases and benign fractures, respectively. CONCLUSION: Our results indicate that quantitative ADC mapping, instead of qualitative diffusion-weighted imaging, can provide valuable information in differentiating benign vertebral fractures from metastatic lesions. 相似文献