全文获取类型
收费全文 | 1413374篇 |
免费 | 104219篇 |
国内免费 | 2202篇 |
专业分类
耳鼻咽喉 | 18497篇 |
儿科学 | 45099篇 |
妇产科学 | 37800篇 |
基础医学 | 208632篇 |
口腔科学 | 37733篇 |
临床医学 | 132597篇 |
内科学 | 279385篇 |
皮肤病学 | 29772篇 |
神经病学 | 116711篇 |
特种医学 | 52009篇 |
外国民族医学 | 278篇 |
外科学 | 200813篇 |
综合类 | 27721篇 |
现状与发展 | 6篇 |
一般理论 | 760篇 |
预防医学 | 115793篇 |
眼科学 | 32234篇 |
药学 | 102262篇 |
7篇 | |
中国医学 | 2202篇 |
肿瘤学 | 79484篇 |
出版年
2021年 | 11818篇 |
2019年 | 12410篇 |
2018年 | 16327篇 |
2017年 | 12455篇 |
2016年 | 13742篇 |
2015年 | 15955篇 |
2014年 | 22199篇 |
2013年 | 34039篇 |
2012年 | 46984篇 |
2011年 | 50017篇 |
2010年 | 28791篇 |
2009年 | 27566篇 |
2008年 | 47409篇 |
2007年 | 50579篇 |
2006年 | 49777篇 |
2005年 | 49192篇 |
2004年 | 47255篇 |
2003年 | 45185篇 |
2002年 | 43746篇 |
2001年 | 57276篇 |
2000年 | 57993篇 |
1999年 | 49441篇 |
1998年 | 15350篇 |
1997年 | 13924篇 |
1996年 | 14086篇 |
1995年 | 13244篇 |
1994年 | 12323篇 |
1992年 | 39074篇 |
1991年 | 38488篇 |
1990年 | 37174篇 |
1989年 | 35933篇 |
1988年 | 33374篇 |
1987年 | 32627篇 |
1986年 | 31233篇 |
1985年 | 29566篇 |
1984年 | 22972篇 |
1983年 | 20173篇 |
1982年 | 12739篇 |
1981年 | 11573篇 |
1979年 | 21602篇 |
1978年 | 16177篇 |
1977年 | 13455篇 |
1976年 | 12435篇 |
1975年 | 13305篇 |
1974年 | 16099篇 |
1973年 | 15783篇 |
1972年 | 14841篇 |
1971年 | 13783篇 |
1970年 | 12973篇 |
1969年 | 12253篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
M Ardigo I Malizewsky ML Dell'Anna E Berardesca M Picardo 《Journal of the European Academy of Dermatology and Venereology》2007,21(10):1344-1350
BACKGROUND: Vitiligo is the most common pigmentary disorder with a global incidence from 0.1% to 2% in different geographical areas. Histopathology and histochemistry have shown the reduction of melanocytes in achromic patches, but microscopic changes of lesional and non-lesional skin are still not completely understood. Reflectance confocal microscopy (RCM), based on the different light reflectance index of cutaneous structures, allowed in vivo, en face microscopic evaluation of superficial skin layers with a resolution similar to skin histology. AIM: The purpose of this study was to evaluate RCM features of lesional and non-lesional skin of vitiligo patients. Moreover, re-pigmented areas were taken into consideration in order to evaluate melanocyte response to ultraviolet B (UVB) radiation. SUBJECTS AND METHODS: Sixteen patients of different phototypes affected by active non-segmental vitiligo and 10 controls were enrolled in the study. In vivo skin imaging was done using a commercially available RCM (Lucid, Vivascope 1500. Re-pigmented areas from 6 to 16 patients (after UVB narrow-band therapy) were also examined. RESULTS: Vitiligo lesions showed the disappearance of the bright rings normally seen at the dermo-epidermal junction. Moreover, non-lesional skin of vitiligo patients showed unexpected changes as the presence of half-rings or scalloped border-like features of the bright papillary rings. In re-pigmented areas after UVB narrow band therapy, the presence of activated, dendritic melanocytes was seen. CONCLUSIONS: Considering our results, and following further studies, RCM clinical applications could be used in the therapeutic monitoring and evaluation of the evolution of vitiligo. 相似文献
992.
Aims To measure the prevalence of low high‐density lipoprotein (HDL)‐cholesterol (men < 1.03 mmol/l; women < 1.29 mmol/l) in European Type 2 diabetic patients receiving treatment for dyslipidaemia. Methods The pan‐European Survey of HDL‐cholesterol measured lipids and other cardiovascular risk factors in 3866 patients with Type 2 diabetes and 4436 non‐diabetic patients undergoing treatment for dyslipidaemia in 11 European countries. Results Diabetic patients were more likely to be obese or hypertensive than non‐diabetic patients. Most patients received lifestyle interventions (87%) and/or a statin (89%); treatment patterns were similar between groups. Diabetic patients had [means (SD)] lower HDL‐cholesterol [1.22 (0.37) vs. 1.35 mmol/l (0.44) vs. non‐diabetic patients, P < 0.001] and higher triglycerides [2.32 (2.10) vs. 1.85 mmol/l (1.60), P < 0.001]. More diabetic vs. non‐diabetic patients had low HDL‐cholesterol (45% vs. 30%), high triglycerides (≥ 1.7 mmol/l; 57% vs. 42%) or both (32% vs. 19%). HDL‐cholesterol < 0.9 mmol/l was observed in 18% of diabetic and 12% of non‐diabetic subjects. Differences between diabetic and non‐diabetic groups were slightly greater for women. LDL‐ and total cholesterol were lower in the diabetic group [3.02 (1.05) vs. 3.30 mmol/l (1.14) and 5.12 (1.32) vs. 5.38 mmol/l (1.34), respectively, P < 0.001 for each]. Conclusions Low HDL‐cholesterol is common in diabetes: one in two diabetic women has low HDL‐cholesterol and one diabetic man in four has very low HDL‐cholesterol. Management strategies should include correction of low HDL‐cholesterol to optimize cardiovascular risk in diabetes. 相似文献
993.
994.
995.
Part III of this series of articles, like Part II, reviews the pioneering efforts in the 19th century to improve the quality of artificial teeth. The focus of this article, unlike that of Part II, is specifically modifications in the design of the occlusal anatomy of the 19th century denture teeth, along with the theories of mandibular movement that inspired those modifications. This article concludes the introductory phase of this project, which seeks to unravel the confusing history of the development of (posterior) denture teeth. 相似文献
996.
Brain morphology in first-episode schizophrenic-like psychotic patients: a quantitative magnetic resonance imaging study 总被引:5,自引:0,他引:5
L E DeLisi A L Hoff J E Schwartz G W Shields S N Halthore S M Gupta F A Henn A K Anand 《Neuropsychopharmacology》1991,29(2):159-175
Brain morphology was examined using magnetic resonance imaging in 30 first-episode patients with a schizophreniclike psychosis, 15 chronic schizophrenics, and 20 neurological controls. Statistical analyses of computer-generated measurements of regions of interest were controlled for gender, age, social class, and total brain volume. Lateral ventricular size was increased in both first-episode and chronic schizophrenic patients, with greater significance on the left than on the right side. Only the chronic patients, however, had reduced temporal lobe size, which also was greater on the left side. No major correlations of regional brain morphological measurements with cognitive functioning were found, although some measurements of verbal memory were correlated with parahippocampal size. This is a report of a preliminary study that suggests that some morphological brain changes may be present at the time of first treatment for a psychotic illness, whereas others may occur later in the course of illness. Future prospective studies may determine the clinical significance of these changes and whether they progress with the development of illness chronicity. 相似文献
997.
998.
Trace element status in multiple sclerosis 总被引:1,自引:0,他引:1
We compared trace element status in multiple sclerosis (MS) patients (n = 27) with and without treatment with corticosteroids and groups of healthy subjects. Concentrations of plasma ceruloplasmin, selenium, and zinc and erythrocyte (RBC) glutathione peroxidase, Se, and Zn were similar in all groups. RBC copper concentrations were significantly lower in MS patients than in control subjects (mean +/- SEM: 0.048 +/- 0.005 vs 0.060 +/- 0.002 mumol/g Hb) because of decreased RBC Cu with steroid therapy. RBC Zn-Cu ratios were significantly higher (14.9 +/- 1.0 vs 10.1 +/- 0.3) in MS patients than in control subjects, differing in both groups of MS patients. In MS and control subjects, RBC Cu correlated significantly with RBC Zn (r = 0.56, 0.49). Disease acuity and disability had no effect on trace-mineral status. These data suggest that in MS there is altered Cu and Zn homeostasis that may cause or result from the disease and is influenced by corticosteroid therapy. Systemic trace element alterations might provide clinically useful markers of MS. 相似文献
999.
1000.
This article describes two studies that examine the nature of effective clinical performance among radiologic technology students. The first study includes the perspective of staff technologists on student performance, while the second study includes the perspective of clinical instructors, important dimensions of performance that are identified include organization, relationship with peers and staff, relationships with patients, flexibility, and initiative. These dimensions are linked to specific student behaviors in clinical practice. 相似文献