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   1721篇
  免费   122篇
  国内免费   7篇
耳鼻咽喉   20篇
儿科学   43篇
妇产科学   23篇
基础医学   217篇
口腔科学   46篇
临床医学   214篇
内科学   334篇
皮肤病学   13篇
神经病学   167篇
特种医学   26篇
外科学   242篇
综合类   24篇
预防医学   224篇
眼科学   21篇
药学   120篇
肿瘤学   116篇
  2024年   4篇
  2023年   15篇
  2022年   19篇
  2021年   45篇
  2020年   21篇
  2019年   52篇
  2018年   60篇
  2017年   31篇
  2016年   34篇
  2015年   27篇
  2014年   67篇
  2013年   115篇
  2012年   140篇
  2011年   135篇
  2010年   72篇
  2009年   79篇
  2008年   137篇
  2007年   142篇
  2006年   100篇
  2005年   101篇
  2004年   98篇
  2003年   101篇
  2002年   58篇
  2001年   21篇
  2000年   13篇
  1999年   11篇
  1998年   10篇
  1997年   11篇
  1996年   10篇
  1995年   8篇
  1994年   7篇
  1993年   8篇
  1992年   7篇
  1991年   3篇
  1990年   5篇
  1989年   7篇
  1988年   9篇
  1987年   6篇
  1986年   8篇
  1985年   9篇
  1984年   8篇
  1983年   7篇
  1982年   5篇
  1979年   3篇
  1976年   2篇
  1975年   2篇
  1974年   4篇
  1973年   3篇
  1969年   2篇
  1968年   2篇
排序方式: 共有1850条查询结果,搜索用时 6 毫秒
81.
BackgroundStigmatization of persons living with obesity is an important public health issue. In 2015, Obesity Canada adopted person-first language in all internal documentation produced by the organization, and, from 2017, required all authors to use person-first language in abstract submissions to Obesity Canada hosted conferences. The impact of this intentional shift in strategic focus is not known. Therefore, the aim of this study was to conduct a content analysis of proceedings at conferences hosted by Obesity Canada to identify whether or how constructs related to weight bias and obesity stigma have changed over time.MethodsOf 1790 abstracts accepted to conferences between 2008–2019, we excluded 353 abstracts that featured animal or cellular models, leaving 1437 abstracts that were reviewed for the presence of five constructs of interest and if they changed over time: 1) use of person-first versus use of disease-first terminology, 2) incorporation of lived experience of obesity, 3) weight bias and stigma, 4) aggressive or alarmist framing and 5) obesity framed as a modifiable risk factor versus as a disease. We calculated and analyzed through linear regression: 1) the overall frequency of use of each construct over time as a proportion of the total number of abstracts reviewed, and 2) the ratio of abstracts where the construct appeared at least once based on the total number of abstracts.ResultsWe found a significant positive correlation between use of person-first language in abstracts and time (R2 = 0.51, p < 0.01 for frequency, R2 = 0.65, p < 0.05 for ratio) and a corresponding negative correlation for the use of disease-first terminology (R2 = 0.48, p = 0.01 for frequency, R2 = 0.75, p < 0.001 for ratio). There was a significant positive correlation between mentions of weight bias and time (R2 = 0.53 and 0.57, p < 0.01 for frequency and ratio respectively).ConclusionUse of person-first language and attention to weight bias increased, while disease-first terminology decreased in accepted abstracts over the past 11 years since Obesity Canada began hosting conferences and particularly since more explicit actions for expectations to use person-first language were put in place in 2015 and 2017.  相似文献   
82.
ObjectivesAlthough pertussis vaccines have been widely used for many decades, a burden of illness persists. Resurgences in Ontario, Canada, have not been substantial in the past decade, but an outbreak of pertussis occurred in Toronto between 1 October 2005 and 31 March 2006. Previous Ontario studies found high vaccine effectiveness (VE) in the initial years post-immunization. In order to explore the impact of outbreaks and external factors on VE, we investigated pertussis VE during the period 2006–2008.MethodsWe assessed pertussis VE using a frequency-matched case-control study for the period 1 March 2006 to 31 December 2008. We used logistic regression to estimate VE by age, time since last vaccination, and vaccination status according to the Ontario recommended schedule. We compared analyses including and excluding cases from Toronto, and to two recent Ontario pertussis VE studies.ResultsWe included 1797 confirmed cases and 7188 matched controls. Most cases were under 4 years of age during the study period. Pertussis VE was 3.8% (95% CI: − 21.0, 24.0) in the period 15–364 days following the last pertussis vaccine dose, and increased with increasing time since vaccination. Pertussis VE in the first 15–364 days excluding Toronto increased to 57.1% (95% CI: 26.0, 75.1), but the trend of increasing VE with time since vaccination persisted. Although VE was higher in older (6–11 years) than younger (0–5 years) children, it was lower at 12–13 years than after 14 years.ConclusionVE was lower in comparison with other studies conducted in Ontario, particularly in younger children. Various factors occurring during the study period may have influenced the results, including clinical testing of asymptomatic contacts, laboratory testing and methods and reporting practice, and a sensitive case definition. Further studies are needed to optimize methods for measuring VE to inform pertussis vaccine policy.  相似文献   
83.
Reproted two investigations. In the first, 40 mental health professionals rated the Bem Masculinity and Femininity Scale items for personality adjustment level. Our female judges gave the Masculinity items higher ratings than the Femininity items, but no difference appeared in the mean ratings of the male judges. Five items then were deleted from each scale to provide modified measures apparently matched for adjustment value. In the second study (N = 106) the MMPI scores, vocational satisfaction scores, and job tenures of psychiatric patients categorized as androgynous, masculine, feminine, or undifferentiated were compared. Significant differences appeared on three MMPI measures when the original scales were used to define gender type, but not when the adjustment-matched scales were used and Ss with invalid MMPIs were deleted. Thus previous findings interpreted as supporting the view that androgyny and masculinity are associated with good adjustment may be artifacts that resulted from differences in the adjustment values of the original scales.  相似文献   
84.
OBJECTIVES: The authors examined patterns of benzodiazepine use in older adults. Specifically, they describe prevalence and incidence of benzodiazepine use during the index year, describe persistence and intensity of benzodiazepine use over a 4-year period; and examine factors associated with benzodiazepine use in the upcoming year. METHODS: Authors performed a secondary analysis of data collected as part of a health promotion intervention trial conducted from 1986 to 1992 in older health maintenance organization enrollees (N=1,505). Benzodiazepine use was ascertained from computerized pharmacy records. Demographic characteristics, health status, and health behaviors were ascertained from mailed questionnaires. RESULTS: During the index year, the prevalence and incidence of benzodiazepine use was 12.3% and 6.6%, respectively. Of those using during the index year, 16% of new users and 63% of previous users continued to use for the following 3 years. The factors significantly associated with benzodiazepine use in the following year were female gender, high school education, higher chronic disease score, higher levels of self-reported pain and stress, low-to-normal body mass index (BMI), and self-reported nervous disorder. CONCLUSIONS: New users had low intensity of use and a low probability of continuing use over the following 3 years. A very small percentage of this sample had evidence of daily use for 4 years. Of concern, benzodiazepines were used by the segment of the sample that were at greatest risk for hip fractures (women with normal/low BMI). Clinicians should assess the need for continued benzodiazepine use at regular intervals.  相似文献   
85.
86.
BACKGROUND: In October 2002, ultrasound-guided, vacuum-assisted, percutaneous excision was shown to facilitate the complete removal of benign breast lesions up to 3 cm in diameter. This study was performed to ascertain the overall accuracy of ultrasound-guided, vacuum-assisted, percutaneous excision as evidenced by the frequency of atypical ductal hyperplasia (ADH) underestimation. STUDY DESIGN: A retrospective review was conducted of 542 consecutive ultrasound-guided, vacuum-assisted breast biopsies performed between February 2000 and September 2004. Before July 2002, no attempt was made to completely remove all imaged lesion evidence. After July 2002, all patients underwent complete percutaneous excision of all imaged lesion evidence. Pathology review revealed 52 lesions that demonstrated ADH and no evidence of malignancy. Each patient with this diagnosis was offered surgical excision. Pathologic reports for each group were compared with the subsequent open surgical specimens. RESULTS: Of 542 consecutively diagnosed lesions, 52 displayed ADH with no evidence of malignancy (10%). Five patients refused operation. Of the 47 patients who underwent open excision, 6 (13%) were found to have malignancies. The rate of ADH underestimation was 6 of 18 (33%) in incisional biopsies and 0 of 29 performed with complete imaged lesion evidence (p=0.002). The rate of ADH underestimation in women who underwent ultrasound-guided, vacuum-assisted, percutaneous excision was zero, a result equivalent to open surgical biopsy. CONCLUSIONS: ADH is a more common finding in sonographic lesions than has been previously reported. Complete ultrasound-guided, vacuum-assisted, percutaneous excision is more accurate than nonexcisional ultrasound-guided biopsy. Patients so diagnosed have very low underestimation rates and may not require open surgical reexcision.  相似文献   
87.
88.
Overeaters Anonymous (OA) is a 12‐step, self‐help group for individuals who perceive themselves to have problems with compulsive overeating. Despite the popularity of OA and the frequent use of addictions‐based treatments for eating disorders, little is known about how OA is helpful. The purpose of this qualitative study was to explore members' experiences with and perceptions of OA. We conducted three focus groups with self‐selected members of OA (N = 20). We present three primary themes that emerged from the analysis of the focus groups' discussions, which emphasize why individuals entered OA, OA's ‘tools’, and how individuals perceived OA to ‘work’. Overall, although participants agreed OA was helpful to them, there was no consensus regarding how OA ‘works’. Copyright © 2009 John Wiley & Sons, Ltd and Eating Disorders Association.  相似文献   
89.

Background  

In June 2009, the World Health Organization declared an A(H1N1) influenza pandemic. In October 2009, the largest vaccination campaign in Canadian history began. The aim of this study was to document paediatricians' knowledge, attitudes and practices (KAP) regarding A(H1N1) pandemic influenza and its prevention by vaccination just after the beginning of the A(H1N1) vaccination campaign and to compare the results with those obtained before campaign initiation.  相似文献   
90.
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