全文获取类型
收费全文 | 47869篇 |
免费 | 2596篇 |
国内免费 | 165篇 |
专业分类
耳鼻咽喉 | 873篇 |
儿科学 | 1683篇 |
妇产科学 | 817篇 |
基础医学 | 6200篇 |
口腔科学 | 1073篇 |
临床医学 | 3689篇 |
内科学 | 11761篇 |
皮肤病学 | 1596篇 |
神经病学 | 4290篇 |
特种医学 | 1321篇 |
外科学 | 5898篇 |
综合类 | 221篇 |
一般理论 | 19篇 |
预防医学 | 4000篇 |
眼科学 | 1161篇 |
药学 | 2849篇 |
中国医学 | 146篇 |
肿瘤学 | 3033篇 |
出版年
2024年 | 49篇 |
2023年 | 336篇 |
2022年 | 479篇 |
2021年 | 1242篇 |
2020年 | 699篇 |
2019年 | 1308篇 |
2018年 | 1711篇 |
2017年 | 1139篇 |
2016年 | 1142篇 |
2015年 | 1299篇 |
2014年 | 1465篇 |
2013年 | 2040篇 |
2012年 | 3471篇 |
2011年 | 3761篇 |
2010年 | 1999篇 |
2009年 | 1634篇 |
2008年 | 3031篇 |
2007年 | 3203篇 |
2006年 | 2972篇 |
2005年 | 2923篇 |
2004年 | 2674篇 |
2003年 | 2528篇 |
2002年 | 2331篇 |
2001年 | 1194篇 |
2000年 | 1426篇 |
1999年 | 1107篇 |
1998年 | 314篇 |
1997年 | 243篇 |
1996年 | 212篇 |
1995年 | 152篇 |
1994年 | 112篇 |
1993年 | 96篇 |
1992年 | 361篇 |
1991年 | 267篇 |
1990年 | 234篇 |
1989年 | 172篇 |
1988年 | 168篇 |
1987年 | 172篇 |
1986年 | 126篇 |
1985年 | 120篇 |
1984年 | 95篇 |
1983年 | 75篇 |
1982年 | 31篇 |
1981年 | 40篇 |
1980年 | 35篇 |
1979年 | 63篇 |
1976年 | 33篇 |
1974年 | 34篇 |
1973年 | 41篇 |
1972年 | 32篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Annika Reintam Pille Parm Uwe Redlich Liina-Mai Tooding Joel Starkopf Friedrich Köhler Claudia Spies Hartmut Kern 《BMC gastroenterology》2006,6(1):19-7
Background
While gastrointestinal problems are common in ICU patients with multiple organ failure, gastrointestinal failure has not been given the consideration other organ systems receive. The aim of this study was to evaluate the incidence of gastrointestinal failure (GIF), to identify its risk factors, and to determine its association with ICU mortality. 相似文献102.
Montse García Elvira Méndez Cristina Martínez Mercè Peris Esteve Fernández 《European journal of cancer prevention》2006,15(5):446-452
The objective of the study was to describe the implementation of measures for preventing tobacco consumption developed in the Catalan Network of Smoke-free Hospitals. Information from 25 hospitals that are actively involved in the Catalan Network of Smoke-free Hospitals (April 2004) was used. The degree of implementation of the Smoke-free Hospitals Project was analysed by means of the Self-Audit Questionnaire of the European Network for Smoke-free Hospitals; each hospital was analysed globally and according to the duration of its Network membership (<1 year: implementation stage; > or =1 year: consolidation stage). In terms of global indicators, there were high levels of commitment (64.8%), communication (74.7%), tobacco control (77.4%) and implementation of smoke-free environments (81.0%). A lower degree of implementation (<50%) was found in education and training, health promotion and healthy workplaces. According to the duration of Network membership, significant differences were observed for communication, environment, healthy workplaces and follow-up. Deficits were observed in areas such as specialist training and cessation support, and further input is required here. By identifying areas needing attention, providing a guide for policy development and by administering it periodically, one can ensure that progress is kept on track. 相似文献
103.
Thorsten Gerstner Deike Buesing Elke Longin Claudia Bendl Dieter Wenzel Brigitte Scheid Gisela Goetze Alfons Macke Gerhard Lippert Wolfgang Klostermann Geert Mayer Regine Augspach-Hofmann Sabine Fitzek Carl-Albrecht Haensch Markus Reuland Stephan A Koenig 《Seizure》2006,15(6):443-448
Valproic acid (VPA) is a broad-spectrum antiepileptic drug and is usually well-tolerated. Rare serious complications may occur in some patients, including haemorrhagic pancreatitis, bone marrow suppression, VPA-induced hepatotoxicity and VPA-induced encephalopathy. The typical signs of VPA-induced encephalopathy are impaired consciousness, sometimes marked EEG background slowing, increased seizure frequency, with or without hyperammonemia. There is still no proof of causative effect of VPA in patients with encephalopathy, but only of an association with an assumed causal relation. We report 19 patients with VPA-associated encephalopathy in Germany from the years 1994 to 2003, none of whom had been published previously. 相似文献
104.
Hemobilia. 总被引:1,自引:0,他引:1
D Va?ó J García-Cano J Gómez-Ruiz G Arranz 《Revista española de enfermedades digestivas》2006,98(3):216-217
105.
106.
Abnormalities of thirst regulation in patients with chronic renal failure on hemodialysis. 总被引:3,自引:0,他引:3
A Martinez-Vea C García J Gaya F Rivera J A Oliver 《American journal of nephrology》1992,12(1-2):73-79
To determine whether thirst mechanisms are altered in nondiabetic patients with chronic renal failure on hemodialysis, 4 patients with an average weight gain between dialysis sessions of more than 5% of dry body weight (group I), 5 patients with less than 3% weight gain (group II), and a group of 6 healthy subjects (group III) were submitted to infusion of hypertonic saline. After infusion the subjects had free access to water. Thirst was evaluated by visual analogue rating scales. Despite similar increments of effective plasma osmolality during saline infusion, patients of group I were thirstier than groups II and III (p less than 0.005 and p less than 0.01, respectively). Changes in thirst ratings were similar in groups II and III. Osmotic thresholds for thirst onset were similar in groups II and III (288.9 +/- 8.5 and 289.8 +/- 3.4 mosm/kg, respectively), but lower in group I (277.6 +/- 7.6 mosm/kg). Nevertheless, great variations were observed in the latter group. Thus, 2 patients showed thresholds for thirst within the normal range, whereas the others had low osmolar thresholds for thirst and baseline plasma osmolalities and high basal thirst scores. During the drinking period, the patients of group I drank more (14.2 +/- 2.8 ml/kg) than those of groups II (5.3 +/- 1.6 ml/kg; p less than 0.02) and III (10.2 +/- 1.6 ml/kg; n.s.) The plasma levels of angiotensin II in uremic patients were higher than in healthy subjects, although there were no differences between groups I and II and no correlation between basal angiotensin II levels and the interdialytic weight gain.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
107.
Two new cases of prostatic blue nevus are studied with routine histological, immunohistochemical and ultrastructural methods. Both cases showed a chronic lower urinary tract obstruction due to a benign prostatic hyperplasia with spindle-shaped stromal cells loaded with melanin pigment. These cells were positive for S-100 and negative for HMB-45 antibodies, being, to the best of our knowledge, the first time that this antibody has been tested in prostatic pigmented lesions. The electron-microscopy study was performed in the first case, confirming the nature of these pigmented cells as melanocytes derived from the neural crest showing melanosomes in all the stages of differentiation and without complete basal cell membrane. The histogenesis of pigmented lesions of the prostate and the differences between blue nevus and melanosis are discussed, and the literature is reviewed. 相似文献
108.
Gavin C. Jones Mireille N. Vankemmelbeke Jan H. Verheijen Claudia DeDood Anthony J. Day David J. Buttle 《International journal of experimental pathology》2004,85(4):A66-A67
Introduction In combination with the catalytic domain, the ancillary domains of the ADAMTS' are proposed to regulate activity via interactions with sulfated GAGs, the extracellular matrix (ECM) and cell surface. Interactions with both GAGs and the ECM have been attributed to the thrombospondin (TSP) type 1 motifs and spacer region ( Kuno and Matsushima 1998 ; Flannery et al. 2002 ). ADAMTS‐1, ‐4 and ‐5, all undergo cleavage within their respective spacer regions ( Flannery et al. 2002 ; Rodriguez‐Manzaneque et al. 2000 ; Georgiadis et al. 2002 ), an event which has been reported to increase activity towards the interglobular domain of aggrecan and decrease the heparin affinity of ADAMTS‐4 ( Flannery et al. 2002 ; Gao et al. 2002 ). Materials and methods V5‐ and His‐tagged recombinant human ADAMTS‐4 constructs terminating after the catalytic (?DTS), disintegrin‐like (?TS), TSP (?S) or spacer region (Full) were expressed in High‐Five cells. Proteoglycanase activities of the resultant proteins were assayed with solution digests of aggrecan and a polyacrylamide‐entrapped aggrecan particle assay. Proteolytic activity was measured using a novel, nonglycosylated, reporter substrate assay. Results All forms of ADAMTS‐4 were active to varying degrees in the reporter substrate assay. Digestion of aggrecan in solution digests was apparent in all proteins with the exception of the catalytic domain in isolation (?DTS). Activity towards aggrecan decreased with increasing truncation of the protein. Discussion Removal of the cysteine‐rich‐spacer domain and further C‐terminal truncations decrease the activity of ADAMTS‐4 towards aggrecan, whilst the proteolytic activity remains intact. Cleavages releasing the ancillary domains of ADAMTS' may therefore alter the catalytic activity of these enzymes against proteoglycans and also nonglycosylated polypeptides. More information is required about potential substrates for the processed forms of ADAMTS‐4. 相似文献
109.
Ana P Martinez-Donate Melbourne F Hovell Elaine J Blumberg Jennifer A Zellner Carol L Sipan Audrey M Shillington Claudia Carrizosa 《AIDS education and prevention》2004,16(2):172-186
Adolescents are at increasing risk for HIV infection in Mexico. Research on gender differences in risk behaviors and determinants is needed to develop effective HIV prevention interventions targeting Mexican adolescents. This study examined gender differences in the likelihood of unprotected sex and theoretical correlates among high school students in the border city of Tijuana. Three hundred seventy high-school students completed a face-to-face interview and a self-administered survey. Differences in sexual initiation, condom use, intentions to use condoms in the future, and attitudes towards condoms in this population were assessed. Although male students initiated sexual practices earlier than females, females were more likely to have unprotected sex. Females perceived themselves as more likely to avoid unprotected sex in the future and held more favorable attitudes about condoms. The results suggest that stereotypical gender roles and communication barriers place Tijuana female high school students at higher risk for HIV infection than their male peers. 相似文献
110.
Michael Gerharz MD ; Ankev Baranowsky PhD ; Udo Siebolts MD ; Sabine Eming MD ; Roswitha Nischt PhD ; Thomas Krieg PhD ; Claudia Wickenhauser MD 《Wound repair and regeneration》2007,15(1):105-112
Morphometric data based on skin wounding offer important information for the characterization of the phenotype of transgenic mouse models. The goal of this study was the comparison of technical procedures concerning wounding, processing, and evaluation of samples in different mouse strains. The multitissue array technique was used to estimate its adaptability for standardized analysis in wound healing. Skin wounds between days 1 and 14 after wounding were analyzed. The influence of mouse strain (C57BI/6 vs. FVB/N mice), sex, size of the punch biopsies, and preparation of the tissue sections was investigated on 94 mice. The parameters distance between the migration tongues (deltaMT) and surface not covered by epithelium were evaluated to describe the reepithelialization, and the distance between the adnexa was chosen to measure wound contraction. In addition, the techniques to measure the area of granulation tissue (GT) were evaluated. The data illustrate the requirement of standardized conditions for skin wound-healing experiments and demonstrate that histological preparation in serial sections is mandatory to detect slight differences in wound contraction. For the analysis of cellular composition in GT, multitissue arrays are useful tools in wound-healing studies. 相似文献