全文获取类型
收费全文 | 4599篇 |
免费 | 384篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 42篇 |
儿科学 | 135篇 |
妇产科学 | 95篇 |
基础医学 | 573篇 |
口腔科学 | 73篇 |
临床医学 | 723篇 |
内科学 | 668篇 |
皮肤病学 | 269篇 |
神经病学 | 616篇 |
特种医学 | 109篇 |
外科学 | 469篇 |
综合类 | 46篇 |
一般理论 | 11篇 |
预防医学 | 576篇 |
眼科学 | 38篇 |
药学 | 274篇 |
中国医学 | 5篇 |
肿瘤学 | 268篇 |
出版年
2024年 | 12篇 |
2023年 | 44篇 |
2022年 | 71篇 |
2021年 | 171篇 |
2020年 | 111篇 |
2019年 | 155篇 |
2018年 | 175篇 |
2017年 | 136篇 |
2016年 | 112篇 |
2015年 | 131篇 |
2014年 | 146篇 |
2013年 | 258篇 |
2012年 | 318篇 |
2011年 | 362篇 |
2010年 | 199篇 |
2009年 | 156篇 |
2008年 | 272篇 |
2007年 | 319篇 |
2006年 | 279篇 |
2005年 | 260篇 |
2004年 | 235篇 |
2003年 | 204篇 |
2002年 | 174篇 |
2001年 | 44篇 |
2000年 | 55篇 |
1999年 | 36篇 |
1998年 | 35篇 |
1997年 | 26篇 |
1996年 | 21篇 |
1995年 | 17篇 |
1994年 | 19篇 |
1993年 | 13篇 |
1992年 | 22篇 |
1991年 | 31篇 |
1990年 | 31篇 |
1989年 | 27篇 |
1988年 | 25篇 |
1987年 | 20篇 |
1986年 | 30篇 |
1985年 | 23篇 |
1984年 | 21篇 |
1983年 | 13篇 |
1982年 | 11篇 |
1981年 | 15篇 |
1980年 | 17篇 |
1979年 | 13篇 |
1978年 | 13篇 |
1974年 | 17篇 |
1972年 | 13篇 |
1971年 | 11篇 |
排序方式: 共有4990条查询结果,搜索用时 0 毫秒
1.
Interaction effects between the 5‐hydroxy tryptamine transporter‐linked polymorphic region (5‐HTTLPR) genotype and family conflict on adolescent alcohol use and misuse
下载免费PDF全文
![点击此处可从《Addiction (Abingdon, England)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
2.
Katherine A Hillman Tanya M Johnson Paul J D Winyard Geoffrey Burnstock Robert J Unwin Adrian S Woolf 《Experimental nephrology》2002,10(1):34-42
BACKGROUND: Purinergic receptors are cell-surface molecules that bind extracellular nucleotides, notably ATP. The P2X family includes seven nonselective ion channels with one member, P2X(7), implicated in cytolytic pore formation and cell death. MATERIALS AND METHODS: We sought P2X(7) expression in mouse nephrogenesis and cpk/cpk renal cyst growth, conditions in which both proliferation and apoptosis are prominent. RESULTS: P2X(7) immunolocalized to condensed metanephric mesenchyme: both proliferation and apoptosis were detected in this compartment, assessed by proliferating cell nuclear antigen expression and propidium iodide-stained pyknotic nuclei respectively. Later in nephrogenesis, P2X(7) was detected in collecting ducts, a pattern persisting to maturity. A mesenchymal to epithelial shift of P2X(7) expression was also documented in ureter development. In cpk/cpk kidneys, P2X(7)-expressing collecting duct cysts dominated histology from two weeks until four weeks after birth, when animals die from uremia. In polycystic kidneys pyknotic nuclei were rarely identified in P2X(7)-expressing epithelia, but were detected between cysts, consistent with a non-apoptotic role for P2X(7) in cyst enlargement. CONCLUSION: P2X(7) is expressed during normal nephrogenesis and in a model of congenital polycystic kidney disease. Further experiments are necessary to define possible functions of P2X(7) in these settings. 相似文献
3.
4.
Lungiswa L Nkonki Tanya M Doherty Zelee Hill Mickey Chopra Nikki Schaay Carl Kendall 《AIDS research and therapy》2007,4(1):27
Background
The objective of this study was to examine missed opportunities for participation in a prevention of mother-to-child transmission (PMTCT) programme in three sites in South Africa. A rapid anthropological assessment was used to collect in-depth data from 58 HIV-positive women who were enrolled in a larger cohort study to assess mother-to-child HIV transmission. Semi-structured interviews were conducted with the women in order to gain an understanding of their experiences of antenatal care and to identify missed opportunities for participation in PMTCT. 相似文献5.
Mark Sisco MD ; Jerome D. Chao MD ; Injoong Kim MD ; Jon E. Mogford PhD ; Tanya N. Mayadas PhD ; Thomas A. Mustoe MD 《Wound repair and regeneration》2007,15(4):566-571
The Mac-1 integrin is an important mediator of migration and inflammatory activation of neutrophils and monocytes. However, the role of Mac-1 in modulating macrophage emigration and activation and its subsequent impact on cutaneous wound healing have not been fully elucidated. To examine the significance of Mac-1 to murine wound healing, we measured epithelialization and granulation tissue formation in partial-thickness ear wounds and full-thickness head wounds, respectively, in Mac-1-deficient mice. Wounds were histologically analyzed at postwounding days 3, 5, and 7. The gap measured between the leading edges of inward-migrating granulation tissue was significantly increased in knockout mice compared with control animals at day 5 (3.8+/-0.3 vs. 2.6+/-0.5 mm; p<0.001) and day 7 (2.2+/-0.4 vs. 0.96+/-0.73 mm; p=0.005). Epithelial gap measurements were also increased in knockout mice vs. wild-type controls at days 3 (0.62+/-0.02 vs. 0.54+/-0.07 mm; p<0.05) and 5 (0.58+/-0.06 vs. 0.39+/-0.08 mm; p<0.001). Immunohistochemistry showed equal numbers of macrophages in knockout and control wounds. These findings show that Mac-1 is required for normal wound healing but that the attenuation in the deposition of granulation tissue and wound epithelialization in Mac-1 knockout mice is not associated with decreased monocyte migration into the wound. 相似文献
6.
Topical Metronidazole Gel 总被引:1,自引:0,他引:1
Joseph A. Witkowski M.D. Lawrence Charles Parish M.D. 《International journal of dermatology》1991,30(9):660-661
Ten putrid-smelling decubitus ulcers were successfully treated with metronidazole gel. Anaerobes were cultured from five ulcers and Wood's light examination was positive in four ulcers before treatment. The odor was eliminated after 36 hours of therapy. All results of post-treatment cultures of anaerobes and Wood's light examinations were negative. 相似文献
7.
8.
Motility disorders of the gastrointestinal (GI) tract have traditionally been diagnosed by excluding mechanical small-bowel obstruction. In order to diagnose GI motility disorders in a positive fashion, small-bowel manometry was performed on 15 patients who were referred to the authors with intestinal motility disorders. Intestinal manometry was performed after first positioning a 200-cm multilumen tube into the small intestine. Ports located at 10-cm intervals were perfused with sterile water and connected to pressure transducers to record intraluminal pressures with a multichannel chart recorder. This low compliance water perfusion manometry system allowed examination of both fasting and postprandial motility. Intestinal manometry was able to assist in the diagnosis of two patients that had true mechanical small-bowel obstruction. One patient had a stenosis of the gastrojejunostomy and three patients had a functional gastric outlet obstruction secondary to a motility disorder in the Roux limb. One patient had a functional obstruction from a reversed jejunal loop and eight patients were identified as having intestinal pseudo-obstruction. We found intestinal manometry was a helpful adjunct in the diagnosis of GI motility disorders. 相似文献
9.
The stability of phenytoin in blood collected in plain and serum separator tubes (SSTs) was investigated under simulated storage and transport conditions. The drug was generally more stable in plain collection tubes than in SSTs. No degradation occurred in plain red-top tubes or in refrigerated SSTs, but clinically significant degradation was present in SSTs stored at room temperature (25 degrees C) and at elevated temperature (32 degrees C) 24 h after collection. The mean loss was 17.9% at 25 degrees C and 25.9% at 32 degrees C. It is recommended that if blood is to be transported or stored in SSTs, the samples be refrigerated unless assay can be performed within 8 h. 相似文献
10.
Detecting pediatric autoimmune neuropsychiatric disorders associated with streptococcus in children with obsessive-compulsive disorder and tics. 总被引:6,自引:0,他引:6
Tanya K Murphy Muhammad Sajid Ohel Soto Nathan Shapira Paula Edge Mark Yang Mark H Lewis Wayne K Goodman 《Neuropsychopharmacology》2004,55(1):61-68
BACKGROUND: A subgroup of children with obsessive-compulsive and tic disorders are proposed to have an infectious trigger. The purpose of this study was to investigate the relationship between group A streptococcal titers and symptom fluctuations in children with a clinical course resembling that described for pediatric autoimmune neuropsychiatric disorders associated with streptococcus. METHODS: Twenty-five children with obsessive-compulsive disorder and/or tic disorder were evaluated for neuropsychiatric severity and group A streptococcal antibody titers (streptolysin O, deoxyribonuclease B, and carbohydrate A) at 6-week intervals for > or = six consecutive evaluations (total visits=277). RESULTS: Children with large symptom fluctuations (n=15) were compared with children without dramatic fluctuations (n=10). Co-movements of obsessive-compulsive/tic severity and group A streptococcal antibodies were assessed. In subjects with large symptom changes, positive correlations were found between streptococcal titers and obsessive-compulsive severity rating changes (p=.0130). These subjects were also more likely to have elevated group A streptococcal titers during the majority of observations (p=.001). Tic symptom exacerbations occurred more often in the fall/winter months than spring/summer months (p=.03). CONCLUSIONS: Patients with marked obsessive-compulsive/tic symptom changes may be characterized by streptococcal titer elevations and exhibit evidence of seasonal tic exacerbations. 相似文献