全文获取类型
收费全文 | 178802篇 |
免费 | 11474篇 |
国内免费 | 707篇 |
专业分类
耳鼻咽喉 | 2503篇 |
儿科学 | 4876篇 |
妇产科学 | 3435篇 |
基础医学 | 23184篇 |
口腔科学 | 3546篇 |
临床医学 | 17506篇 |
内科学 | 38299篇 |
皮肤病学 | 2801篇 |
神经病学 | 17952篇 |
特种医学 | 6213篇 |
外国民族医学 | 13篇 |
外科学 | 26475篇 |
综合类 | 2301篇 |
现状与发展 | 3篇 |
一般理论 | 201篇 |
预防医学 | 13295篇 |
眼科学 | 4781篇 |
药学 | 11512篇 |
中国医学 | 203篇 |
肿瘤学 | 11884篇 |
出版年
2023年 | 697篇 |
2022年 | 1222篇 |
2021年 | 2862篇 |
2020年 | 1761篇 |
2019年 | 2885篇 |
2018年 | 3396篇 |
2017年 | 2453篇 |
2016年 | 2859篇 |
2015年 | 3454篇 |
2014年 | 5106篇 |
2013年 | 7877篇 |
2012年 | 11387篇 |
2011年 | 12248篇 |
2010年 | 6835篇 |
2009年 | 6304篇 |
2008年 | 11531篇 |
2007年 | 12296篇 |
2006年 | 11797篇 |
2005年 | 12159篇 |
2004年 | 11551篇 |
2003年 | 11025篇 |
2002年 | 10635篇 |
2001年 | 1484篇 |
2000年 | 1123篇 |
1999年 | 1591篇 |
1998年 | 2329篇 |
1997年 | 2020篇 |
1996年 | 1702篇 |
1995年 | 1581篇 |
1994年 | 1423篇 |
1993年 | 1352篇 |
1992年 | 1042篇 |
1991年 | 953篇 |
1990年 | 834篇 |
1989年 | 816篇 |
1988年 | 837篇 |
1987年 | 718篇 |
1986年 | 835篇 |
1985年 | 915篇 |
1984年 | 1221篇 |
1983年 | 1173篇 |
1982年 | 1639篇 |
1981年 | 1512篇 |
1980年 | 1416篇 |
1979年 | 785篇 |
1978年 | 906篇 |
1977年 | 800篇 |
1976年 | 707篇 |
1975年 | 566篇 |
1974年 | 593篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
121.
122.
123.
Donald B. Penzien PhD ; Frank Andrasik PhD ; Brian M. Freidenberg PhD ; Timothy T. Houle PhD ; Alvin E. Lake III PhD; Gay L. Lipchik PhD ; Kenneth A. Holroyd PhD ; Richard B. Lipton MD ; Douglas C. McCrory MD ; Justin M. Nash PhD ; Robert A. Nicholson PhD ; Scott W. Powers PhD ABPP ; Jeanetta C. Rains PhD ; David A. Wittrock PhD 《Headache》2005,45(S2):S110-S132
Guidelines for design of clinical trials evaluating behavioral headache treatments were developed to facilitate production of quality research evaluating behavioral therapies for management of primary headache disorders. These guidelines were produced by a Workgroup of headache researchers under auspices of the American Headache Society. The guidelines are complementary to and modeled after guidelines for pharmacological trials published by the International Headache Society, but they address methodologic considerations unique to behavioral and other nonpharmacological treatments. Explicit guidelines for evaluating behavioral headache therapies are needed as the optimal methodology for behavioral (and other nonpharmacologic) trials necessarily differs from the preferred methodology for drug trials. In addition, trials comparing and integrating drug and behavioral therapies present methodological challenges not addressed by guidelines for pharmacologic research. These guidelines address patient selection, trial design for behavioral treatments and for comparisons across multiple treatment modalities (eg, behavioral vs pharmacologic), evaluation of results, and research ethics. Although developed specifically for behavioral therapies, the guidelines may apply to the design of clinical trials evaluating many forms of nonpharmacologic therapies for headache. 相似文献
124.
Herlinde Dumez Gunther Guetens Gert De Boeck Martin S Highley Robert A A Maes Allan T van Oosterom Ernst A de Bruijn 《Clinical chemistry and laboratory medicine》2004,42(11):1219-1227
Therapeutic drug monitoring generally focuses on the plasma compartment only. Differentiation between the total plasma concentration and the free fraction (plasma water) has been described for a number of limited drugs. Besides the plasma compartment, blood has also a cellular fraction which has by far the largest theoretical surface and volume for drug transport. It is with anti-cancer drugs that major progress has been made in the study of partition between the largest cellular blood compartment, i.e., erythrocytes, and the plasma compartment. The aim of the present review is to detail the progress made in predicting what a drug does in the body, i.e., pharmacodynamics including toxicity and plasma and/or red blood cell concentration monitoring. Furthermore, techniques generally used in anti-cancer drug monitoring are highlighted. Data for complex Bayesian statistical approaches and population kinetics studies are beyond the scope of this review, since this is generally limited to the plasma compartment only. 相似文献
125.
Michael J. Bernas Robert L. Askew Jane M. Armer Janice N. Cormier 《Current breast cancer reports》2010,2(1):53-58
Lymphedema is an under-recognized, progressive, life-long condition estimated to impact 2-3 million people in the United States.
The incidence of breast cancer related lymphedema varies greatly in the literature largely due to different measurement techniques,
competing thresholds for defining lymphedema, and variation in length of follow-up. Multiple imaging techniques have become
useful for diagnosis. Lymphoscintigraphy is one of the most commonly used, as it can identify pathways of lymphatic drainage,
quantify extent of dermal backflow, and help determine functional and morphologic changes in the lymphatic system. Early detection
and intervention hold the greatest promise of reducing the incidence of lymphedema. Health care providers involved with cancer
patients need to become more educated about lymphedema, aware of current risk-reduction practices, and familiar with methods
of diagnosis and assessment, so that patients with early swelling can be referred to lymphedema treatment specialists at a
time when treatment is more effective. 相似文献
126.
127.
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
128.
Robert B. Forbes David J. Murray Judith B. Dillman David L. Dull 《Journal canadien d'anesthésie》1989,36(2):160-164
Plasma methohexitone concentrations were determined in 60 children, aged one to six years, following administration of 15 mg.kg-1, 20 mg.kg-1, 25 mg.kg-1 or 30 mg.kg-1 two per cent rectal methohexitone. Time to the onset of sleep was determined by a blinded observer and venous blood samples obtained 15, 30, 45 and 120 minutes following drug administration. Fifty of 60 children were asleep within 15 minutes. Nine of the ten children that did not fall asleep were sedate and could be separated easily from their parents to undergo inhalational induction of anesthesia. Time to the onset of sleep was inversely related to the dose of rectal methohexitone administered. Sleep was achieved more reliably following the use of 25 to 30 mg.kg-1 rectal methohexitone. In addition, plasma methohexitone concentrations following 30 mg.kg-1 rectal methohexitone were significantly higher for up to 120 minutes following drug administration than the plasma concentrations achieved after 15 mg.kg-1 or 20 mg.kg-1 methohexitone. There was no difference in the incidence of complications. The authors recommend that clinical circumstances be carefully considered and the dose of rectal methohexitone administered be individualized to meet the specific anaesthetic requirements of each child. 相似文献
129.
The surgical risk of colectomy in patients with cirrhosis 总被引:5,自引:1,他引:4
Dr. Amanda Mary Teresa Metcalf M.D. Roger R. Dozois M.D. Bruce G. Wolff M.D. Robert W. Beart Jr. M.D. 《Diseases of the colon and rectum》1987,30(7):529-531
The records of 54 patients with documented cirrhosis who underwent colectomy between January 1970 and January 1984 were studied to assess the operative risk and to determine the preoperative predictive risk factors. In-hospital mortality was 24 percent (13 patients), and postoperative complications occurred in 48 percent (26 patients). The risk of surgical intervention was significantly increased if encephalopathy, ascites, anemia, or hypoalbuminemia was present before operation. A simple operative risk index involving the presence of encephalopathy and ascites and the levels of hemoglobin and albumin is proposed to help distinguish a low-risk subgroup in whom postoperative mortality was 12.8 percent from a high-risk subgroup in whom postoperative mortality was 53.3 percent. 相似文献
130.
Martinus A H Capelle Robert Gurny Tudor Arvinte 《European journal of pharmaceutics and biopharmaceutics》2007,65(2):131-148
The formulation of protein drugs is a difficult and time-consuming process, mainly due to the complexity of protein structure and the very specific physical and chemical properties involved. Understanding protein degradation pathways is essential for the success of a biopharmaceutical drug. The present review concerns the application of high throughput screening techniques in protein formulation development. A protein high throughput formulation (HTF) platform is based on the use of microplates. Basically, the HTF platform consists of two parts: (i) sample preparation and (ii) sample analysis. Sample preparation involves automated systems for dispensing the drug and the formulation ingredients in both liquid and powder form. The sample analysis involves specific methods developed for each protein to investigate physical and chemical properties of the formulations in microplates. Examples are presented of the use of protein intrinsic fluorescence for the analysis of protein aqueous properties (e.g., conformation and aggregation). Different techniques suitable for HTF analysis are discussed and some of the issues concerning implementation are presented with reference to the use of microplates. 相似文献