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   2204篇
  免费   276篇
  国内免费   7篇
耳鼻咽喉   4篇
儿科学   92篇
妇产科学   91篇
基础医学   177篇
口腔科学   52篇
临床医学   168篇
内科学   490篇
皮肤病学   35篇
神经病学   182篇
特种医学   14篇
外科学   163篇
综合类   14篇
一般理论   2篇
预防医学   626篇
眼科学   25篇
药学   117篇
中国医学   1篇
肿瘤学   234篇
  2024年   4篇
  2023年   59篇
  2022年   50篇
  2021年   85篇
  2020年   85篇
  2019年   98篇
  2018年   112篇
  2017年   112篇
  2016年   85篇
  2015年   94篇
  2014年   128篇
  2013年   265篇
  2012年   95篇
  2011年   100篇
  2010年   106篇
  2009年   122篇
  2008年   132篇
  2007年   110篇
  2006年   112篇
  2005年   84篇
  2004年   72篇
  2003年   66篇
  2002年   65篇
  2001年   48篇
  2000年   31篇
  1999年   37篇
  1998年   32篇
  1997年   30篇
  1996年   38篇
  1995年   5篇
  1994年   3篇
  1993年   4篇
  1992年   1篇
  1991年   8篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1986年   1篇
  1983年   2篇
  1982年   1篇
  1980年   1篇
排序方式: 共有2487条查询结果,搜索用时 15 毫秒
41.
The objective of this study was to identify factors that may account for the disproportionately high prevalence of suicidal behaviors among Hispanic/Latina youth by examining whether associations of health risk behaviors with suicidal ideation and suicide attempts vary by race/ethnicity among female students. Data from the school-based 2007 national Youth Risk Behavior Survey were analyzed. Analyses were conducted among female students in grades 9 through 12 and included 21 risk behaviors related to unintentional injuries and violence; tobacco use; alcohol and other drug use; sexual behaviors that contribute to unintended pregnancy and sexually transmitted infections, including human immunodeficiency virus; physical activity; obesity and weight control; and perceived health status. With the exception of physical activity behaviors and obesity, all risk behaviors examined were associated with suicidal ideation and suicide attempts. Associations of risk behaviors with suicidal ideation varied by race/ethnicity for 5 of 21 behaviors, and for 0 of 21 behaviors for suicide attempts. Stratified analyses provided little insight into factors that may account for the higher prevalence of suicidal behaviors among Hispanic/Latina female students. These results suggest that the increased risk of suicidal behaviors among Hispanic/Latina female students cannot be accounted for by differential associations with these selected risk behaviors. Other factors, such as family characteristics, acculturation, and the socio-cultural environment, should be examined in future research.  相似文献   
42.
Objective: To examine the contributions of race and diagnostic category to endorsement rates of challenging behaviours in infants and toddlers with autism, PDD-NOS and atypical development without ASD, using the Baby and Infant Screen for Children with aUtIsm Traits, Part-3 (BISCUIT Part-3).

Design: Multivariate analyses of variance (MANOVAs) on each sub-scale of the BISCUIT Part-3. Follow-up univariate analyses and post-hoc tests as needed.

Methods: Scores on the BISCUIT Part-3 were compared for 453 Caucasian and 409 African-American infants and toddlers, grouped by race and diagnosis.

Results: Significant differences between races were found on five out of 10 aggressive behaviours, while no significant differences were found on self-injurious or stereotypic behaviours. Significant differences between diagnostic groups were found on all behaviours.

Conclusion: Cultural factors should be taken into account when examining challenging behaviours in infants and toddlers with ASD.  相似文献   
43.
44.
45.
AIM: To compare the non-invasive tear film break-up time (NIBUT), tear break up time (TBUT), basal tear secretion (BTS) and blink rate in four ethnic groups: Malay, Chinese, Indian and Nigerian. METHODS: Totally 120 healthy (61 males and 59 females) subjects (without dry eye symptoms and ocular surface disorder) with the age 20 to 39 years were recruited; 30 were Malays, 30 were Chinese, 31 were Indians and 29 were Nigerians. Based on McMonnies questionnaire and clinical examination, normal subjects were selected. NIBUT, TBUT, BTS were assessed in only one eye (right) of each subject and blink rate was also assessed. RESULTS: There was significant difference in the NIBUT, TBUT, BTS and blink rate among 4 different ethnic groups (P=0.018, 0.001, 0.011, and 0.004 respectively). No statistically significant difference of NIBUT, TBUT, BTS and blink rate was found between the genders among different ethnic groups. Indian had higher median for NIBUT (10±6s), TBUT (7±5s) and BTS (20±20 mm) than other races. Chinese had lower median for NIBUT (7.5±4s) and TBUT (4±2s) while Malay had for BTS (9.5±16 mm) among the groups. There was no significant correlation of blink rate with NIBUT (r=-0.119, P=0.195), TBUT (r=-0.086, P=0.352), and BTS (r=-0.123, P=0.180) respectively. CONCLUSION: The tear-film measurement values are variability in four ethnic groups.  相似文献   
46.
47.
ABSTRACT

Objectives: Glioblastoma is the most common primary malignant brain tumor in adults, and despite decades of intensive research regarding its pathophysiology and treatment, the prognosis for glioblastoma patients remains poor. While many studies have analyzed various factors that may influence survival outcomes, the focus of this brief review is to discuss the influence that apatient’s race/ethnicity has on survival. This factor has been investigated in large population-based studies and in smaller institutional analyses, but the prognostic utility of this factor has been inconsistent. Discussion of this topic is therefore warranted to better equip providers to counsel and treat patients with glioblastoma, as well as to identify areas of future research.

Methods: A comprehensive literature search is performed to identify studies that reported GBM survival outcomes by race/ethnicity.

Results: Although some discrepancies exist, asignificant survival benefit is associated with the Asian or Pacific Islander (API) race, whereas white patients have the poorest survival and highest incidence. Hispanic patients tend to fare better than white patients but have worse survival than APIs.

Discussion: Further analysis into the differences in survival among different races may lead to an increased understanding of potential molecular and genetic targets, thus guiding future treatment plans for these patients.

Abbreviations: AAAIR: Average Annual Age-Adjusted Incidence Rate; AI/AN: American Indian or Alaska Native; API: Asian or Pacific Islander; CBTRUS: Central Brain Tumor Registry of the United States; CUMC: Columbia University Medical Center; EOR: Extent of Resection; Exc: Excluded; GBM: Glioblastoma; GTR: Gross Total Resection; IDH-1: Isocitrate Dehydrogenase 1; MGMT: O6-Methylguanine DNA Methyltransferase; NCDB: National Cancer Database; OS: Overall Survival; O/U: Other/Unknown; PFS: Progression-Free Survival; SEER: Surveillance, Epidemiology, and End Results; S&W BTR: Scott & White Brain Tumor Registry; UCLA: University of California Los Angeles; UM: University of Miami.  相似文献   
48.
Background Attitudes to the inclusion of people with intellectual disabilities (IDs) have been studied extensively, yet evidence on public awareness about ID and stigma is limited. The relationship between attitudes, knowledge and stigma associated with ID is poorly understood. The present study examined these factors and the relationships between them in the context of a multicultural society. Method UK residents of working age (n = 1002) were presented with a diagnostically unlabelled vignette of someone with a mild ID. They were asked to label the difficulties presented and to complete measures of social distance and attitudes to the inclusion of people with IDs. Results While attitudes to the inclusion of people with IDs were relatively positive overall, social contact was viewed with ambivalence. Inclusion attitudes and social distance were only moderately correlated. Across the whole sample 28% recognised typical symptoms of mild ID. Recognition of ID was associated with lower stigma and more positive attitudes than attribution of the difficulties presented to other causes. White Westerners showed increased knowledge, lower stigma and favoured inclusion more than participants from ethnic minorities. Among the latter group, Asians showed lower stigma and attitudes more in line with inclusion policies than participants of Black African/Caribbean backgrounds. Once a host of contextual factors were considered jointly, only contact was consistently associated with the variables measured. Conclusions Stigma associated with ID is of concern across all ethnic groups, although it appears to be increased among the public from ethnic minorities. Given that contact and awareness are associated with reduced stigma, they should be considered as prime foci for efforts to tackle ID stigma. The current findings serve as baseline for attempts to increase public awareness and tackle stigma.  相似文献   
49.
Introduction: Artemisinin-based combination therapy (ACT) is used extensively as first-line treatment for uncomplicated falciparum malaria. There has been no rigorous assessment of the potential for racial/ethnic differences in the pharmacokinetic properties of ACTs that might influence their efficacy.

Areas covered: A comprehensive literature search was performed that identified 72 publications in which the geographical origin of the patients could be ascertained and the key pharmacokinetic parameters maximum drug concentration (Cmax), area under the plasma concentration-time curve (AUC) and elimination half-life (t½β) were available for one or more of the five WHO-recommended ACTs (artemether-lumefantrine, artesunate-amodiaquine, artesunate-mefloquine, dihydroartemisinin-piperaquine and artesunate-sulfadoxine-pyrimethamine). Comparisons of each of the three pharmacokinetic parameters of interest were made by drug (artemisinin derivative and long half-life partner), race/ethnicity (African, Asian, Caucasian, Melanesian, South American) and patient categories based on age and pregnancy status.

Expert opinion: The review identified no evidence of a clinically significant influence of race/ethnicity on the pharmacokinetic properties of the nine component drugs in the five ACTs currently recommended by WHO for first-line treatment of uncomplicated falciparum malaria. This provides reassurance for health workers in malaria-endemic regions that ACTs can be given in recommended doses with the expectation of adequate blood concentrations regardless of race/ethnicity.  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