全文获取类型
收费全文 | 1110篇 |
免费 | 46篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 53篇 |
妇产科学 | 19篇 |
基础医学 | 144篇 |
口腔科学 | 32篇 |
临床医学 | 140篇 |
内科学 | 247篇 |
皮肤病学 | 40篇 |
神经病学 | 26篇 |
特种医学 | 182篇 |
外科学 | 105篇 |
综合类 | 40篇 |
预防医学 | 48篇 |
眼科学 | 9篇 |
药学 | 47篇 |
中国医学 | 2篇 |
肿瘤学 | 32篇 |
出版年
2024年 | 5篇 |
2023年 | 5篇 |
2022年 | 4篇 |
2021年 | 14篇 |
2020年 | 17篇 |
2019年 | 20篇 |
2018年 | 19篇 |
2017年 | 20篇 |
2016年 | 22篇 |
2015年 | 28篇 |
2014年 | 32篇 |
2013年 | 46篇 |
2012年 | 40篇 |
2011年 | 27篇 |
2010年 | 57篇 |
2009年 | 46篇 |
2008年 | 32篇 |
2007年 | 40篇 |
2006年 | 25篇 |
2005年 | 28篇 |
2004年 | 26篇 |
2003年 | 34篇 |
2002年 | 29篇 |
2001年 | 18篇 |
2000年 | 26篇 |
1999年 | 21篇 |
1998年 | 45篇 |
1997年 | 41篇 |
1996年 | 41篇 |
1995年 | 26篇 |
1994年 | 37篇 |
1993年 | 32篇 |
1992年 | 24篇 |
1991年 | 16篇 |
1990年 | 14篇 |
1989年 | 27篇 |
1988年 | 23篇 |
1987年 | 18篇 |
1986年 | 16篇 |
1985年 | 14篇 |
1984年 | 6篇 |
1983年 | 12篇 |
1982年 | 13篇 |
1981年 | 10篇 |
1980年 | 14篇 |
1979年 | 4篇 |
1978年 | 6篇 |
1977年 | 13篇 |
1976年 | 9篇 |
1975年 | 7篇 |
排序方式: 共有1171条查询结果,搜索用时 15 毫秒
41.
42.
RM Bologa DM Levine TS Parker JS Cheigh D Serur KH Stenzel AL Rubin 《American journal of kidney diseases》1998,32(1):107-114
Low serum albumin and low serum cholesterol levels are among the most consistent predictors of mortality in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Hypoalbuminemia is often interpreted as a marker of poor nutrition, but serum albumin and cholesterol levels can also be low as part of a cytokine-mediated acute-phase reaction to acute or chronic inflammation. Here we report the results from a 900-day prospective study designed to determine whether tumor necrosis factor-alfa (TNF-alpha) and interleukin-6 (IL-6) predict serum albumin and cholesterol levels and mortality in a group of 90 ambulatory, adult hemodialysis patients with no acute infection, hospitalization or surgery, and no known acquired immunodeficiency syndrome (AIDS), malignancy, or liver disease. Measurable levels of TNF-alpha and/or IL-6 were found in 89 of 90 patients. Significant relationships were found between TNF-alpha and IL-6 and the degree of hypoalbuminemia and dyslipoproteinemia. IL-6 was the strongest predictor of mortality in univariate and multivariate analysis, followed by age, albumin level, and body mass index (BMI). Although the cause of hypercytokinemia was not addressed in this study, the data support the view that hypoalbuminemia and hypocholesterolemia are negative acute-phase responses to inflammatory stimuli. These results suggest that efforts to identify the nature of the stimuli for cytokine production and to lower cytokine levels in hemodialysis patients might be effective in improving the survival of patients undergoing hemodialysis. 相似文献
43.
Detection of the Philadelphia chromosome in acute lymphoblastic leukemia by pulsed-field gel electrophoresis 总被引:1,自引:0,他引:1
The Philadelphia (Ph1) chromosome is an acquired abnormality in the malignant cells of 10% to 25% of patients with acute lymphoblastic leukemia (ALL). Unlike chronic myelogenous leukemia (CML), where the molecular detection of the Ph1 chromosome is relatively straightforward using conventional Southern hybridization analysis, the detection of the Ph1 chromosome in ALL is complicated by the existence of several molecular subtypes, and the fact that translocation breakpoints are dispersed over a large genomic area. To circumvent these difficulties, we investigated pulsed-field gel electrophoresis (PFGE) to determine if this method could be used directly on clinical samples to detect the Ph1 chromosome in ALL. We report that, in a study of seven patients with Ph1-positive ALL, we could easily detect the Ph1 using only a single PFGE analysis, regardless of the Ph1 subtype, and we could confirm that the translocations occur either within or very near the BCR gene in all seven. We conclude that PFGE is a useful technique for the detection of the Ph1 in ALL, which ultimately may find wide applicability in the detection of other chromosomal abnormalities in other malignancies. 相似文献
44.
Robert PH Berr C Volteau M Bertogliati C Benoit M Sarazin M Legrain S Dubois B;PréAL study 《Clinical neurology and neurosurgery》2006,108(8):733-736
OBJECTIVE: To evaluate the relation between apathy and development of dementia in patients with amnestic mild cognitive impairment (MCI). METHODS: Two hundred and fifty-one French-speaking outpatients fulfilling the criteria of amnestic MCI were enrolled. Apathy was assessed with the Apathy Inventory (IA). Neuropsychiatric evaluation also included the Goldberg anxiety scale and the Montgomery and Asberg Depressive Rating Scale (MADRS). The main end point considered after a 1-year follow-up was the development of dementia of Alzheimer type (DAT). RESULTS: At baseline there were 86 (39.8%) subjects presenting at least one symptom of apathy among the 216 included in analysis. After a 1-year follow-up, 22 patients developed DAT. Of the patients with apathy at baseline 13 (15.1%) developed DAT in comparison with 9 (6.9%) of the non-apathetic patients. At the 1-year follow-up, patients developing DAT had a significantly higher frequency of apathetic symptoms (91.7%) than patients without DAT (26.9%). CONCLUSION: Taking into account that apathy is one of the most frequently observed neuropsychiatric symptoms in MCI and in DAT the present study suggests that patients with MCI and apathy should be more closely observed. 相似文献
45.
Interaction of high molecular weight kininogen, factor XII, and fibrinogen in plasma at interfaces 总被引:5,自引:0,他引:5
Using ellipsometry, anodized tantalum interference color, and Coomassie blue staining in conjunction with immunologic identification of proteins adsorbed at interfaces, we have previously found that fibrinogen is the main constituent deposited by plasma onto many man- made surfaces. However, the fibrinogen deposited from normal plasma onto glass and similar wettable materials is rapidly modified during contact activation until it can no longer be identified antigenically. In earlier publications, we have called this modification of the fibrinogen layer "conversion," to indicate a process of unknown nature. Conversion of adsorbed fibrinogen by the plasma was not accompanied by marked change in film thickness, so that we presumed that this fibrinogen was not covered but replaced by other protein. Conversion is now showen to be markedly delayed in plasma lacking high molecular weight kininogen, slightly delayed in plasma lacking factor XII, and normal in plasma that lack factor XI or prekallikrein. We conclude that intact plasma will quickly replace the fibrinogen it has deposited on glass-like surfaces by high molecular weight kininogen and, to a smaller extent, by factor XII. Platelets adhere preferentially to fibrinogen-coated surfaces; human platelets adhere to hydrophobic nonactivating surfaces, since on these, adsorbed firbinogen is not exchanged by the plasma. The adsorbed fibrinogen will be replaced on glass-like surfaces during surface activation of clotting, and platelets failing to find fibrinogen will not adhere. 相似文献
46.
47.
48.
M. M. Verbeek E. A. Notting B. Faas R. Claessens‐Linskens P. J. H. Jongen 《Acta neurologica Scandinavica》2010,121(5):309-314
Verbeek MM, Notting EA, Faas B, Claessens‐Linskens R, Jongen PJH. Increased cerebrospinal fluid chitotriosidase index in patients with multiple sclerosis.Acta Neurol Scand: 2010: 121: 309–314.© 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objective – To investigate chitotriosidase (CTTS) activity in serum and cerebrospinal fluid (CSF) in multiple sclerosis (MS) patients in relation to disease course and CSF markers for immune activation or inflammation. Materials and methods – We studied 80 patients with relapsing–remitting MS (RRMS), 24 with secondary progressive MS (SPMS), 20 with primary progressive MS (PPMS) and 29 patients with other neurological disorders (OND). We measured CTTS activity and studied the correlation with CSF mononuclear cell count (MNC) and intrathecal IgG production. Results – CTTS activity was significantly higher in CSF, but not in serum, from the total MS group compared with OND and controls. In RRMS and SPMS CTTS, index was increased compared with controls (RRMS, 0.10 ± 0.21; SPMS, 0.10 ± 0.15; controls, 0.021 ± 0.020), but not in PPMS (0.061 ± 0.052). CTTS index was higher in MS patients with elevated MNC or CSF‐restricted oligoclonal IgG bands than in MS patients without these CSF findings. Conclusions – CTTS index is elevated in RRMS and SPMS. The CTTS index is related to CSF markers of inflammation or immune activation. 相似文献
49.
50.