首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   12025篇
  免费   1280篇
  国内免费   27篇
耳鼻咽喉   101篇
儿科学   429篇
妇产科学   221篇
基础医学   1556篇
口腔科学   222篇
临床医学   1577篇
内科学   2353篇
皮肤病学   123篇
神经病学   1136篇
特种医学   563篇
外科学   1384篇
综合类   741篇
一般理论   13篇
预防医学   1170篇
眼科学   343篇
药学   741篇
中国医学   8篇
肿瘤学   651篇
  2023年   64篇
  2022年   104篇
  2021年   221篇
  2020年   138篇
  2019年   186篇
  2018年   305篇
  2017年   179篇
  2016年   191篇
  2015年   179篇
  2014年   278篇
  2013年   471篇
  2012年   514篇
  2011年   514篇
  2010年   354篇
  2009年   322篇
  2008年   481篇
  2007年   528篇
  2006年   548篇
  2005年   523篇
  2004年   475篇
  2003年   451篇
  2002年   447篇
  2001年   428篇
  2000年   413篇
  1999年   383篇
  1998年   187篇
  1997年   166篇
  1996年   205篇
  1995年   174篇
  1994年   134篇
  1993年   164篇
  1992年   292篇
  1991年   275篇
  1990年   293篇
  1989年   264篇
  1988年   235篇
  1987年   261篇
  1986年   214篇
  1985年   170篇
  1984年   164篇
  1983年   138篇
  1982年   118篇
  1981年   75篇
  1980年   73篇
  1979年   110篇
  1978年   101篇
  1977年   91篇
  1976年   76篇
  1975年   83篇
  1970年   56篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
A closed femur fracture pain model was developed in the C57BL/6J mouse. One day after fracture, a monoclonal antibody raised against nerve growth factor (anti-NGF) was delivered intraperitoneally and resulted in a reduction in fracture pain-related behaviors of approximately 50%. Anti-NGF therapy did not interfere with bone healing as assessed by mechanical testing and histomorphometric analysis. INTRODUCTION: Current therapies to treat skeletal fracture pain are limited. This is because of the side effect profile of available analgesics and the scarcity of animal models that can be used to understand the mechanisms that drive this pain. Whereas previous studies have shown that mineralized bone, marrow, and periosteum are innervated by sensory and sympathetic fibers, it is not understood how skeletal pain is generated and maintained even in common conditions such as osteoarthritis, low back pain, or fracture. MATERIALS AND METHODS: In this study, we characterized the pain-related behaviors after a closed femur fracture in the C57BL/6J mouse. Additionally, we assessed the effect of a monoclonal antibody that binds to and sequesters nerve growth factor (anti-NGF) on pain-related behaviors and bone healing (mechanical properties and histomorphometric analysis) after fracture. RESULTS: Administration of anti-NGF therapy (10 mg/kg, days 1, 6, and 11 after fracture) resulted in a reduction of fracture pain-related behaviors of approximately 50%. Attenuation of fracture pain was evident as early as 24 h after the initial dosing and remained efficacious throughout the course of fracture pain. Anti-NGF therapy did not modify biomechanical properties of the femur or histomorphometric indices of bone healing. CONCLUSIONS: These findings suggest that therapies that target NGF or its cognate receptor(s) may be effective in attenuating nonmalignant fracture pain without interfering with bone healing.  相似文献   
12.
13.
During the past 10 years, numerous phase I-II studies were conducted and provided clinical experience with combined radiation therapy and hyperthermia treatments. Among the rare complications reported in these combined radiation therapy-hyperthermia trials were myonecrosis and peripheral neuropathy which were felt, mainly on a clinical basis, to be caused by local heat damage. Recently, such complications were noted in two patients with recurrent prostatic cancer treated in our department with radiation therapy combined with deep regional hyperthermia delivered by the Sigma-60 applicator of the BSD 2000 hyperthermia system (Salt Lake City, UT, USA). Analysis of the results of three-dimensional modelling of the SAR (specific absorption rate, W/kg) pattern in these patients indicated high SAR at the sites of the complications. Pretreatment three-dimensional modelling or other methods of predicting potential areas of high power deposition may have a role for future hyperthermia treatment planning aiding in the prevention of possible local heat damage and providing improved delivery of heat to the target volume.  相似文献   
14.
The resazurin reduction test provides an assessment of sperm activity   总被引:1,自引:0,他引:1  
OBJECTIVE: The objective of the study was to determine if reduction of the dye resazurin by semen could be correlated with the concentration of motile sperm. DESIGN: After assessment of sperm count and motility, specimens were incubated for 1 hour with resazurin (25 micrograms/mL of semen) and visual color changes indicative of dye reduction noted. SETTING: Specimens were obtained from men seeking care for infertility at one of four sites: (1) University of California, San Francisco (UCSF) In Vitro Fertilization Program; (2) UCSF Andrology Laboratory; (3) a gynecological practice in Maine; and (4) a private andrology laboratory in Southern California. PATIENTS: Individuals were self-selected by their desire to have a semen analysis in conjunction with the diagnosis or treatment of infertility. INTERVENTIONS: None. MAIN OUTCOME MEASURE: The reduction of the dye resazurin and its correlation with motile sperm density. RESULTS: When the motile sperm concentration was greater than or equal to 20 X 10(6)/mL, 86% of specimens produced a positive color change. Conversely, 86% of specimens with a motile sperm concentration of less than 20 X 10(6)/mL either did not change color or changed only over a narrow range. CONCLUSION: Reduction of resazurin offers an assessment of the active sperm in a specimen without the need to do a sperm count or evaluation of motility.  相似文献   
15.
The type and frequency of spinal therapeutic work being undertaken in the United Kingdom (UK) by clinicians with an interest in the surgcial treatment of disorders of the spine (primary and secondary subspecialty interest) were evaluated by means of a postal questionnaire. The willingness of respondents to take part in postgraduate spinal training was determined along with issues regarding accessibility of spinal services to non-specialist physicians in the health service in the UK. The results of 450 respondents provided insight into the types of procedures taking place, for example: primary spinal decompression was regularly carried out by 76% of surgeons, while at least 20% of respondents regularly carried out 66% of the procedures surveyed. We found that 10% of surgeons indicated that they were prepared to participate actively in postgraduate spinal surgical training.  相似文献   
16.
The complications of diabetes continue to present significant health risks despite improvements in conventional insulin therapy. Transplantation of pancreatic islet tissue has the potential to provide more precise glucose regulation and possibly minimize these implications. Recent advances in pancreatic islet isolation technology have facilitated investigation of islet allograft function in large animal models. These studies are fundamental to the development of methods for transplantation of allogeneic or xenogeneic islets in diabetic patients. This paper reviews the approaches which have been taken to prevent rejection and allow assessment of islet allograft function in the pancreatectomized dog model. These approaches include immunosuppression, immunomodulation of the donor tissue and isolation of allogeneic tissue within an immunoprotective membrane.  相似文献   
17.
Background Down syndrome is one of the commonest causes of intellectual disability. As life expectancy improves with early and more intensive surgical and medical treatments, people with the disorder are more likely to exhibit classic morbidity and mortality patterns and be diagnosed with diseases such as cancer. Methods A profile of cancer cases among people with Down syndrome has been compiled, based on the analysis of a linked data set that included information from the Disability Services Commission of Western Australian and the State Cancer Registry. Results and conclusions Although the total age‐ and sex‐standardized incidence ratios (SIRs) for people with Down syndrome were similar to that for the general population, SIRs for leukaemia were significantly higher while the incidence of certain other types of cancers was reduced. Overall, there was a lower incidence of solid tumours in Down syndrome, possibly reflecting the age profile of the study cohort.  相似文献   
18.
Pharmacy and therapeutics committees commonly cite a lack of generalizability as a reason for not incorporating cost-effectiveness information into decision making. To address this concern, many committees undertake site-specific economic evaluations, which are often limited by small sample sizes and nonrandomized designs. We show how 2 complementary approaches were used to minimize these limitations in an economic evaluation of abciximab at 1 institution. Using a propensity score methodology, we selected patients who did not receive abciximab for the comparison cohort. Then, we adopted a Bayesian, hierarchical, random-effects model to integrate site-specific and clinical trial data. We applied the posterior distributions of effectiveness with local cost data in a traditional decision-analytic model. In 74% of the simulations, abciximab was cost-effective at 1 institution at the $50,000 per life year saved threshold, assuming a 50:50 split of patients undergoing coronary stenting and angioplasty. Among patients undergoing coronary stenting, the cost-effectiveness ratio of the addition of abciximab was at or below the $50,000 per life year saved threshold in 66.0% of the simulations.  相似文献   
19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号