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   252篇
  免费   13篇
  国内免费   2篇
耳鼻咽喉   1篇
儿科学   7篇
妇产科学   1篇
基础医学   28篇
口腔科学   3篇
临床医学   11篇
内科学   95篇
皮肤病学   2篇
神经病学   19篇
特种医学   31篇
外科学   17篇
综合类   3篇
预防医学   12篇
眼科学   3篇
药学   18篇
肿瘤学   16篇
  2021年   5篇
  2020年   2篇
  2018年   6篇
  2017年   5篇
  2016年   1篇
  2015年   6篇
  2014年   8篇
  2013年   9篇
  2012年   11篇
  2011年   11篇
  2010年   10篇
  2009年   9篇
  2008年   12篇
  2007年   13篇
  2006年   6篇
  2005年   3篇
  2004年   6篇
  2003年   3篇
  2002年   7篇
  2001年   1篇
  2000年   6篇
  1999年   3篇
  1998年   11篇
  1997年   15篇
  1996年   13篇
  1995年   4篇
  1994年   2篇
  1993年   2篇
  1992年   11篇
  1991年   4篇
  1990年   2篇
  1989年   8篇
  1988年   5篇
  1987年   4篇
  1986年   4篇
  1985年   11篇
  1984年   3篇
  1983年   4篇
  1981年   3篇
  1980年   2篇
  1977年   2篇
  1976年   3篇
  1975年   1篇
  1974年   2篇
  1971年   1篇
  1970年   1篇
  1969年   1篇
  1967年   1篇
  1966年   1篇
  1965年   1篇
排序方式: 共有267条查询结果,搜索用时 31 毫秒
41.
The femur length/abdominal circumference ratio, expressed as FL/AC X 100, was determined in 156 fetuses and evaluated as a predictor of fetal macrosomia within one week prior to delivery. The normal range (mean +/- 2 SD) in the 105 normal-weight fetuses was 22.0 +/- 2, while the normal range in the 51 macrosomic fetuses was 20.5 +/- 2; these differences were highly significant (P = less than .0001). The predictive power of a positive ratio was 68%, with a sensitivity of 63%. This ratio was particularly useful in the subset (n = 9) of macrosomic fetuses whose mothers were diabetic, correctly identifying 89% of this group. Because it is age independent, this ratio should prove most helpful in identifying fetuses at risk for macrosomia in patients whose dates are not known, since it may become abnormal before the fetal weight falls above the 90th percentile at term (3,900 g). In patients whose dates are known, early fetal macrosomia is best predicted by evaluating the abdominal circumference against normal standards for age.  相似文献   
42.
A previously healthy 56-year-old man presented with chest pain. Echocardiography and cardiac magnetic resonance imaging revealed minimal pericardial effusion associated with an isolated myocardial mass, protruding into the left atrium. The tumor was surgically removed. Cardiac valve morphology was strictly normal. Histology revealed a well-differentiated neuroendocrine carcinoma. Positron emission tomography scan and thin-slice abdominal computed tomography demonstrated ileal tumor, without evidence of liver metastasis. Histological study of the removed ileal tumor confirmed a neuroendocrine carcinoma, and histology of liver biopsy was negative. Somatostatin analogue treatment was started. No tumoral recurrence was observed after 1 year of follow-up. In conclusion, we report an unusual presentation of neuroendocrine carcinoma, revealed by a large solitary atrial metastasis, in the absence of liver involvement or carcinoid syndrome.  相似文献   
43.
44.
Quiescin sulfhydryl oxidase 1 (QSOX1) is a highly conserved disulfide bond-generating enzyme that is overexpressed in diverse tumor types. Its enzymatic activity promotes the growth and invasion of tumor cells and alters extracellular matrix composition. In a nude mouse-human tumor xenograft model, tumors containing shRNA for QSOX1 grew significantly more slowly than controls, suggesting that QSOX1 supports a proliferative phenotype in vivo. High throughput screening experiments identified ebselen as an in vitro inhibitor of QSOX1 enzymatic activity. Ebselen treatment of pancreatic and renal cancer cell lines stalled tumor growth and inhibited invasion through Matrigel in vitro. Daily oral treatment with ebselen resulted in a 58% reduction in tumor growth in mice bearing human pancreatic tumor xenografts compared to controls. Mass spectrometric analysis of ebselen-treated QSOX1 mechanistically revealed that C165 and C237 of QSOX1 covalently bound to ebselen. This report details the anti-neoplastic properties of ebselen in pancreatic and renal cancer cell lines. The results here offer a “proof-of-principle” that enzymatic inhibition of QSOX1 may have clinical relevancy.  相似文献   
45.
DA Christakis  FP Rivara 《Pediatrics》1998,101(5):825-830
BACKGROUND: The increasing complexity of medical care and a desire to increase quality and control costs have led to growing use of clinical practice guidelines (CPGs). It is unclear how helpful these guidelines are to the practitioners expected to use them. We surveyed pediatricians about their knowledge and impressions of four well-publicized CPGs: the American Academy of Pediatrics' "Practice Parameter for Hyperbilirubinemia in Newborns" (hyperbilirubinemia), "A Guideline for the Management of Febrile Infants" (fever), the Agency for Health Care Policy and Research's "Guideline for Otitis Media With Effusion" (otitis), and the US Preventive Services Task Force Guide to Clinical Preventive Services (preventive care). OBJECTIVES: 1) What percentage of practicing pediatricians are aware of these guidelines? 2) How helpful do they find them? 3) What are practitioners' perceived limitations of these guidelines? 4) Have these guidelines affected provider behavior? 5) Are there features of a provider's training or practice that are associated with changing practice as a result of guidelines? DESIGN: A national survey of 600 pediatricians selected at random from the American Medical Association master file. RESULTS: A total of 300 of 555 eligible participants (54%) returned surveys. Of the respondents, 66% were aware of the hyperbilirubinemia guideline, 64% of the fever guideline, 50% of the otitis guideline, but only 16% knew of the preventive care guidelines. Mean helpfulness scores (1 to 10 scale, where 1 = "not at all helpful" and 10 = "extremely helpful") ranged from 3.67 to 6.67 for the different guidelines. In terms of limitations, 15% to 33% of respondents reported that CPGs were "too cookbook," 6% to 19% reported that they were "too time-consuming," and 4% to 16% reported that they were "too cumbersome." Additional reported limitations were believing that a guideline left no room for personal experience and judgment, concern of increased liability risk, and poor parental acceptance of CPG recommendations. The proportions reporting change in management as a result of a CPG were 28% for the hyperbilirubinemia guideline, 36% for the fever guideline, 19% for the preventive care guidelines, and 28% for the otitis guideline. Mean helpfulness scores reported by nonuniversity-affiliated physicians were significantly higher than those reported by university-affiliated physicians. In a regression model of respondents aware of a particular guideline, more recent graduation from medical school and increased helpfulness scores were associated with guideline-related behavior change. CONCLUSION: In their present form, CPGs are not perceived as very helpful by most practitioners. More recent medical school graduates and nonuniversity-affiliated physicians are more likely to find them helpful and more likely to change their behavior because of them.  相似文献   
46.
47.
48.
49.
Medical treatment of patients inherently entails the risk of undesired complication or side effects. It is essential to inform the patient about the expected outcomes, but also the possible undesired outcomes. The patients preference and values regarding the potential outcomes should be involved in the decision making process. Even though many orthopaedic surgeons are positive towards shared decision-making, it is minimally introduced in the orthopaedic daily practice and decision-making is still mostly physician based. Decision aids are designed to support the physician and patient in the shared- decision-making process. By using decision aids, patients can learn more about their condition and treatment options in advance to the decision-making. This will reduce decisional conflict and improve participation and satisfaction.  相似文献   
50.
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