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   1937篇
  免费   157篇
  国内免费   7篇
耳鼻咽喉   17篇
儿科学   125篇
妇产科学   18篇
基础医学   313篇
口腔科学   38篇
临床医学   167篇
内科学   405篇
皮肤病学   27篇
神经病学   175篇
特种医学   118篇
外科学   151篇
综合类   33篇
一般理论   9篇
预防医学   168篇
眼科学   42篇
药学   119篇
肿瘤学   176篇
  2021年   22篇
  2019年   24篇
  2018年   41篇
  2017年   17篇
  2016年   29篇
  2015年   18篇
  2014年   26篇
  2013年   52篇
  2012年   63篇
  2011年   68篇
  2010年   42篇
  2009年   41篇
  2008年   76篇
  2007年   59篇
  2006年   68篇
  2005年   72篇
  2004年   75篇
  2003年   45篇
  2002年   59篇
  2001年   53篇
  2000年   59篇
  1999年   58篇
  1998年   37篇
  1997年   32篇
  1996年   16篇
  1995年   24篇
  1994年   20篇
  1993年   15篇
  1992年   50篇
  1991年   57篇
  1990年   54篇
  1989年   53篇
  1988年   62篇
  1987年   59篇
  1986年   64篇
  1985年   43篇
  1984年   45篇
  1983年   35篇
  1982年   26篇
  1980年   18篇
  1979年   42篇
  1978年   20篇
  1977年   21篇
  1976年   20篇
  1975年   23篇
  1974年   27篇
  1973年   25篇
  1971年   23篇
  1969年   14篇
  1966年   16篇
排序方式: 共有2101条查询结果,搜索用时 15 毫秒
41.
PURPOSE: To report the results of a survey of the members of the American Association of Pediatric Ophthalmology and Strabismus (AAPOS) regarding the treatment of periocular capillary hemangiomas. METHODS: A survey was delivered to the 600 members of AAPOS. Surveys were returned via facsimile. Results were collected in a computerized spreadsheet and then tabulated and analyzed. RESULTS: Of the 600 AAPOS members, 225 responded to the survey. The results showed that intralesional steroid injection is the most commonly used treatment modality for periorbital capillary hemangiomas. Oral steroids and excision were also commonly used in the treatment of these lesions. CONCLUSIONS: Further controlled studies are needed to determine which treatment modality offers the most benefit and least risk. More standardization based on these studies is necessary to improve treatment of periocular capillary hemangiomas.  相似文献   
42.
OBJECTIVE: To describe what pediatric primary care providers involved in the Pediatric Research in Office Settings (PROS) research network think are important yet inadequately addressed questions in pediatric primary care research. METHODS: A total of 1785 pediatric primary care providers in the PROS network were asked what they thought were important yet inadequately addressed areas of primary care research. We used a single, open-ended question in a mail survey. Written answers to this question were analyzed by qualitative methods to determine the main themes of interest to pediatric primary care providers. RESULTS: Overall survey response rate was 48.7%; the open-ended question yielded 1109 individual answers. Six lines of inquiry were identified as being important to these providers: (1) effective counseling techniques to use in anticipatory guidance; (2) strategies to prevent and treat obesity; (3) the effectiveness of well-child care; (4) ongoing management of patients with attention-deficit/hyperactivity disorder; (5) the role of the primary care provider in caring for children with mental health needs; and (6) optimal organization of office practices. CONCLUSIONS: The translation of research into practice may be improved by a better understanding of the needs and interests of those who see pediatric patients in the primary care setting.  相似文献   
43.
PURPOSE: To test the ability of the cytoprotectant, amifostine, to reduce chemoradiotherapy-induced esophagitis and evaluate its influence on quality of life (QOL) and swallowing symptoms. PATIENTS AND METHODS: A total of 243 patients with stage II to IIIA/B non-small-cell lung cancer received induction paclitaxel 225 mg/m(2) intravenously (IV) days 1 and 22 and carboplatin area under the curve (AUC) days 1 and 22, followed by concurrent weekly paclitaxel (50 mg/m(2) IV) and carboplatin (AUC 2), and hyperfractionated radiation therapy (69.6 Gy at 1.2 Gy bid). Patients were randomly assigned at registration to amifostine (AM) 500 mg IV four times per week or no AM during chemoradiotherapy. Beyond standard toxicity end points, physician dysphagia logs (PDLs), daily patient swallowing diaries, and QOL (EORTC QLQ-C30/LC-13) were also collected. Swallowing AUC analyses were calculated from patient diaries and PDLs. RESULTS: A total of 120 patients were randomly assigned to receive AM, and 122, to receive no AM (one patient was ineligible); 72% received AM per protocol or with a minor deviation. AM was associated with higher rates of acute nausea (P = .03), vomiting (P = .007), cardiovascular toxicity (P = .0001), and infection or febrile neutropenia (P = .03). The rate of >/= grade 3 esophagitis was 30% with AM versus 34% without AM (P = .9). Patient diaries demonstrated lower swallowing dysfunction AUC with amifostine (z test P = .025). QOL was not significantly different between the two arms, except for pain, which showed more clinically meaningful improvement and less deterioration at 6 weeks follow-up (v pretreatment) in the AM arm (P = .003). The median survival rates for both arms were comparable (AM, 17.3 v no AM, 17.9 months; P = .87). CONCLUSION: AM did not significantly reduce esophagitis >/= grade 3 in patients receiving hyperfractionated radiation and chemotherapy. However, patient self-assessments suggested a possible advantage to AM that is being explored with modified dosing route strategies.  相似文献   
44.
Pancreatic ductal adenocarcinoma (PDA) remains a deadly disease, affecting about 40,000 individuals in the United States annually. We aimed to characterize the role of RET as a co-driver of pancreas tumorigenesis. To assess the role of RET as a co-driver of PDA, we generated a novel triple mutant transgenic mouse based on the cre-activated p53R172H gene and a constitutively active RET M919T mutant (PRC). Survival analysis was performed using Kaplan–Meier analysis. Study of human PDA specimens and Pdx-1-Cre/KrasG12D /p53R172H (KPC) mice revealed that RET is upregulated during pancreas tumorigenesis, from inception through precursor lesions, to invasive cancer. We demonstrated that activation of RET is capable of inducing invasive pancreatic carcinomas in the background of the P53 inactivation mutation. Compared to KPC mice, PRC animals had distinct phenotypes, including longer latency to tumor progression, longer survival, and the presence of multiple macrometastases. Enhanced activation of the MAPK pathway was observed as early as the PanIN 2 stage. Sequencing of the exonic regions of KRAS in PRC-derived PDA cells revealed no evidence of KRAS mutations. RET can be an essential co-driver of pancreatic tumorigenesis in conjugation with KRAS activity. These data suggest that RET may be a potential target in the treatment of PDA.  相似文献   
45.
46.
Hospital-onset Clostridium difficile infection (CDI) places a significant burden on health care systems throughout Europe, estimated at around €3 billion per annum. This burden is shared between national payers and hospitals that support additional bed days for patients diagnosed with CDI while in hospital or patients re-admitted from a previous hospitalisation. This study was performed to quantify additional hospital stay attributable to CDI in four countries, England, Germany, Spain, and The Netherlands, by analysing nationwide hospital-episode data. We focused upon patients at increased risk of CDI: with chronic obstructive pulmonary disease, heart failure, diabetes, or chronic kidney disease, and aged 50 years or over. Multivariate regression and propensity score matching models were developed to investigate the impact of CDI on additional length of hospital stay, controlling for confounding factors such as underlying disease severity. Patients in England had the longest additional hospital stay attributable to CDI at 16.09 days, followed by Germany at 15.47 days, Spain at 13.56 days, and The Netherlands at 12.58 days, derived using regression analysis. Propensity score matching indicated a higher attributable length of stay of 32.42 days in England, 15.31 days in Spain, and 18.64 days in The Netherlands. Outputs from this study consistently demonstrate that in European countries, for patients whose hospitalisation is complicated by CDI, the infection causes a statistically significant increase in hospital length of stay. This has implications for optimising resource allocation and budget setting at both the national and hospital level to ensure that levels of CDI-complicated hospitalisations are minimised.  相似文献   
47.
48.
49.
50.
Advances in next‐generation sequencing (NGS) technologies have helped reveal causal variants for genetic diseases. In order to establish causality, it is often necessary to compare genomes of unrelated individuals with similar disease phenotypes to identify common disrupted genes. When working with cases of rare genetic disorders, finding similar individuals can be extremely difficult. We introduce a web tool, GeneYenta, which facilitates the matchmaking process, allowing clinicians to coordinate detailed comparisons for phenotypically similar cases. Importantly, the system is focused on phenotype annotation, with explicit limitations on highly confidential data that create barriers to participation. The procedure for matching of patient phenotypes, inspired by online dating services, uses an ontology­based semantic case matching algorithm with attribute weighting. We evaluate the capacity of the system using a curated reference data set and 19 clinician entered cases comparing four matching algorithms. We find that the inclusion of clinician weights can augment phenotype matching.  相似文献   
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