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71.
早期蔺草尘肺的HRCT表现 总被引:1,自引:0,他引:1
目的:研究早期蔺草尘肺的HRCT表现。方法:对经高kVp胸片筛选后的47例蔺草作业工人作胸部HRCT扫描并分析CT表现,其中包括25例已被确诊尘肺和22例未能确诊尘肺者。结果:44例显示弥漫性分布的类圆形“P”小结节阴影,包括高kVp胸片尚难以确诊蔺草尘肺的22例,3例上肺野出现大阴影及间质性纤维化。结论:早期的蔺草尘肺结节在肺小叶内呈随机分布,并非仅在小叶中心,细支气管壁和小叶间隔未见增厚,HRCT对显示弥漫性尘肺结节灶及肺间质性改变明显优于胸片。 相似文献
72.
慢性肾功能不全病人胃电图的变化 总被引:4,自引:0,他引:4
目的:为临床对慢性肾功能不全病人进行胃功能改变的诊治提供依据。方法:对73例慢性肾功能不全病人的胃电图变化进行研究。结果:这类病人的主要胃电活动改变为频率加快和胃节律紊乱,胃电频率增快同对照组差异具有显著性(P〈0.05)。结论:胃节律紊乱是导致病人出现消化道症状的主要原因。 相似文献
73.
Rohin K. Iyer Jane Chui Milica Radisic 《Journal of tissue engineering and regenerative medicine》2009,3(3):196-207
Cardiac tissue engineering aims to create myocardial patches for repair of defective or damaged native heart muscle. The inclusion of non‐myocytes in engineered cardiac tissues has been shown to improve the properties of cardiac tissue compared to tissues engineered from enriched populations of myocytes alone. While attempts have been made to mix non‐myocytes (fibroblasts, endothelial cells) with cardiomyocytes, very little is understood about how the tissue properties are affected by varying the respective ratios of the three cell types and how these cells assemble into functional tissues with time. The goal of this study was to investigate the effects of modulating the ratios of the three cell types and to spatially and temporally track cardiac tri‐cultures of cells. Primary neonatal cardiac fibroblasts and D4T endothelial cells were incubated in 5 µM CellTracker? green dye and CellTracker? red dye, respectively, while neonatal cardiomyocytes were labelled with 20 µg/mL DAPI. The non‐myocytes were seeded either sequentially (pre‐culture) or simultaneously (tri‐culture) in Matrigel‐coated microchannels and allowed to form organoids, as in our previous studies. We also varied the seeding percentage of cardiomyocytes while keeping the total cell number constant in an attempt to improve the functional properties of the organoids. Organoids were imaged on days 1 and 4. Endothelial cells were seen to aggregate into clusters when simultaneously tri‐cultured with myocytes and fibroblasts, while pre‐cultures contained elongated cells. Functional properties of organoids were improved by increasing the seeding percentage of enriched cardiomyocytes from 40% to 80%. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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75.
Fast bone segmentation is often important in computer-aided medical systems. Thresholding-based techniques have been widely used to identify the object of interest (bone) against dark backgrounds. However, the darker areas that are often present in bone tissue may adversely affect the results obtained using existing thresholding-based segmentation methods. We propose an automatic, fast, robust and accurate method for the segmentation of bone using 3D adaptive thresholding. An initial segmentation is first performed to partition the image into bone and non-bone classes, followed by an iterative process of 3D correlation to update voxel classification. This iterative process significantly improves the thresholding performance. A post-processing step of 3D region growing is used to extract the required bone region. The proposed algorithm can achieve sub-voxel accuracy very rapidly. In our experiments, the segmentation of a CT image set required on average less than 10 s per slice. This execution time can be further reduced by optimizing the iterative convergence process. 相似文献
76.
Ying Yu Chui Hau Yee Kuan Idy C.Y. Fu Rico K.Y. Liu Mau Kwong Sham & Kam Shing Lau 《Journal of advanced nursing》2009,65(9):1860-1871
Title. Factors associated with lower quality of life among patients receiving palliative care.
Aim. This paper is a report of a study conducted to (1) assess the quality of life (QoL) and physical functioning status of patients diagnosed with advanced cancer and receiving palliative care; (2) determine if there was a statistically significant relationship between their physical functioning and QoL and (3) identify the demographic and disease-related variables related to their QoL.
Background. Achieving the best possible QoL is a major goal in palliative care. However, research findings about the relationship between QoL and demographic variables have been inconsistent.
Method. Three hundred patients with advanced cancer were recruited from four district hospitals in Hong Kong between February 2005 and July 2006. Their QoL and physical functioning status were assessed by face-to-face interview, using the McGill Quality of Life Questionnaire (Hong Kong version) and the Palliative Performance Scale respectively.
Results. Participants reported reduced ambulation, inability to perform hobbies or housework, and the need for occasional assistance in self-care (mean: 64·6 out of 100, sd : 19·3, range: 20–100). QoL was fair (mean: 6·2 out of 10, sd : 1·5, range: 0·9–10). There was a weak positive association between physical functioning and QoL scores. Multiple regression analysis showed that patients who were older, female, had ever been married, or had higher physical functioning tended to have better QoL.
Conclusion. More could be done in symptom and psychosocial management to improve patients' QoL, in particular for those who are younger, male or single, or who have lower physical functioning. 相似文献
Aim. This paper is a report of a study conducted to (1) assess the quality of life (QoL) and physical functioning status of patients diagnosed with advanced cancer and receiving palliative care; (2) determine if there was a statistically significant relationship between their physical functioning and QoL and (3) identify the demographic and disease-related variables related to their QoL.
Background. Achieving the best possible QoL is a major goal in palliative care. However, research findings about the relationship between QoL and demographic variables have been inconsistent.
Method. Three hundred patients with advanced cancer were recruited from four district hospitals in Hong Kong between February 2005 and July 2006. Their QoL and physical functioning status were assessed by face-to-face interview, using the McGill Quality of Life Questionnaire (Hong Kong version) and the Palliative Performance Scale respectively.
Results. Participants reported reduced ambulation, inability to perform hobbies or housework, and the need for occasional assistance in self-care (mean: 64·6 out of 100, sd : 19·3, range: 20–100). QoL was fair (mean: 6·2 out of 10, sd : 1·5, range: 0·9–10). There was a weak positive association between physical functioning and QoL scores. Multiple regression analysis showed that patients who were older, female, had ever been married, or had higher physical functioning tended to have better QoL.
Conclusion. More could be done in symptom and psychosocial management to improve patients' QoL, in particular for those who are younger, male or single, or who have lower physical functioning. 相似文献
77.
Memory impairment is observed in adults with type 2 diabetes mellitus (T2DM), with further acute deficits after meal ingestion. This study explored whether postprandial oxidative stress was a contributor to these meal-induced memory deficits. Sixteen adults with T2DM (mean age, 63.5 ± 2.1 years) who were not regularly taking high-dose antioxidant supplements were fed a high-fat meal, the same test meal with vitamins C (1000 mg) and E (800 IU) tablets, or water on 3 separate occasions. After meal ingestion, a battery of cognitive tests were administered, which included measures of delayed verbal memory, assessed at 60 and 105 minutes after meal ingestion. Relative to water consumption, the high-fat meal resulted in poorer performance at 105 minutes postingestion on measures of delayed verbal recall (word list and paragraph recall) and working memory (Digit-Span Forward). Coconsumption of antioxidant vitamins and high-fat meal prevented this meal-induced deficit such that performance on these tasks was indistinguishable from that after water intake. At the same time point, a small but significant improvement on the word-naming and color-naming components of Stroop was observed after meal ingestion, relative to water, irrespective of whether antioxidants were consumed, demonstrating the specificity of meal-induced impairments to memory function. Executive function, assessed by Trails Parts A and B, was not influenced by meal or antioxidant ingestion. In adults with T2DM, coconsumption of antioxidant vitamins minimizes meal-induced memory impairment, implicating oxidative stress as a potential contributor to these decrements. 相似文献
78.
79.
Chun Hay Ko Karen Li Pak Cheung Ng Kwok Pui Fung Raymond Pui-On Wong Kit Man Chui Goldie Jia-Shi Gu Edmund Yung Tai Fai Fok 《Toxicology in vitro》2008,22(5):1222-1227
Glucose-6-phosphate dehydrogenase (G6PD)-deficient subjects are susceptible to chemical-induced oxidative haemolysis. Little is known concerning the haemolytic properties of Chinese herbal medicine on G6PD-deficient subjects. Our objective was to investigate the pro-oxidative effect of 18 commonly used Chinese herbal medicine (CHM) on human G6PD-deficient red blood cells. G6PD-deficient (n=10) and normal (n=10) whole blood samples were incubated with water extracts of CHM. The resulting levels of reduced glutathione (GSH) and methaemoglobin (MetHb) were determined by biochemical assays. Rhizoma Coptidis significantly reduced GSH level by 48.9+/-5.4% (at 1 mg/mL) in the G6PD-deficient erythrocytes (P<0.001) compared with the respective control group without challenge. Similar dose-dependent responses were observed at higher concentrations of Cortex Moutan, Radix Rehmanniae, Radix Bupleuri, Rhizoma Polygoni Cuspidati and Flos Chimonanthi (P<0.01, 5-10 mg/mL). In addition, the levels of MetHb were elevated significantly when challenged with Rhizoma Coptidis (2.8 fold at 5 mg/mL) and Cortex Moutan (3.4 fold at 10 mg/mL). This is the first report on the pro-oxidative action of CHM on G6PD-deficient blood samples in vitro as demonstrated by the decrease of GSH and increase of MetHb. G6PD-deficient subjects should restrain from excessive consumption of these pro-oxidative herbs. 相似文献
80.