全文获取类型
收费全文 | 980篇 |
免费 | 21篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 12篇 |
妇产科学 | 37篇 |
基础医学 | 89篇 |
口腔科学 | 7篇 |
临床医学 | 42篇 |
内科学 | 152篇 |
皮肤病学 | 12篇 |
神经病学 | 73篇 |
特种医学 | 10篇 |
外科学 | 130篇 |
综合类 | 11篇 |
预防医学 | 285篇 |
眼科学 | 9篇 |
药学 | 41篇 |
中国医学 | 2篇 |
肿瘤学 | 88篇 |
出版年
2023年 | 34篇 |
2022年 | 40篇 |
2021年 | 41篇 |
2020年 | 51篇 |
2019年 | 48篇 |
2018年 | 44篇 |
2017年 | 40篇 |
2016年 | 21篇 |
2015年 | 18篇 |
2014年 | 66篇 |
2013年 | 59篇 |
2012年 | 39篇 |
2011年 | 63篇 |
2010年 | 50篇 |
2009年 | 71篇 |
2008年 | 75篇 |
2007年 | 48篇 |
2006年 | 44篇 |
2005年 | 26篇 |
2004年 | 16篇 |
2003年 | 15篇 |
2002年 | 17篇 |
2001年 | 9篇 |
2000年 | 4篇 |
1999年 | 12篇 |
1998年 | 6篇 |
1997年 | 7篇 |
1996年 | 6篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 5篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1983年 | 6篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有1005条查询结果,搜索用时 671 毫秒
91.
92.
Rebbeca N. Hutchinson Mary A. Putt Lorraine T. Dean Judith A. Long Chantal A. Montagnet Katrina Armstrong 《Social science & medicine (1982)》2009
Neighborhood characteristics such as racial composition and social capital have been widely linked to health outcomes, but the direction of the relationship between these characteristics and health of minority populations is controversial. Given this uncertainty, we examined the relationship between neighborhood racial composition, social capital, and black all-cause mortality between 1997 and 2000 in 68 Philadelphia neighborhoods. Data from the U.S. Census, the Philadelphia Health Management Corporation's 2004 Southeast Pennsylvania Community Health Survey, and city vital statistics were linked by census tract and then aggregated into neighborhoods, which served as the unit of analysis. Neighborhood social capital was measured by a summative score of respondent assessments of: the livability of their community, the likelihood of neighbors helping one another, their sense of belonging, and the trustworthiness of their neighbors. After adjustment for the sociodemographic characteristics of neighborhood residents, black age-adjusted all-cause mortality was significantly higher in neighborhoods that had lower proportion of black residents. Neighborhood social capital was also associated with lower black mortality, with the strongest relationship seen for neighborhoods in the top half of social capital scores. There was a significant interaction between racial composition and social capital, so that the effect of social capital on mortality was greatest in neighborhoods with a higher proportion of black residents and the effect of racial composition was greatest in neighborhoods with high social capital. These results demonstrate that age-adjusted all-cause black mortality is lowest in mostly black neighborhoods with high levels of social capital in Philadelphia. 相似文献
93.
Ricciardi R Selker HP Baxter NN Marcello PW Roberts PL Virnig BA 《Surgical endoscopy》2008,22(9):1977-1986
Background Disparities in outcome across race and ethnicity have been consistently described for medical and surgical care. Given that
surgery is a rapidly evolving field, we hypothesized that racial disparities exist in access to minimally invasive surgery
(MIS), which importantly influences outcome.
Methods Cohort analysis of all patients who underwent appendectomy, gastric fundoplication, and gastric bypass in the Nationwide Inpatient
Sample, a 20% stratified random sample of US hospital discharge abstracts. To determine the effect of race on the use of MIS
techniques and morbidity and mortality, we controlled for patient characteristics, comorbidity, and hospital characteristics
including surgical volume and MIS conversion to open surgery.
Results Blacks were consistently less likely to be treated with MIS despite adjustment for socioeconomic status, comorbidity, and
treatment setting. In addition, in-hospital mortality and complications such as pneumonia, heart disease, infections, and
surgical misadventures were higher in black than white patients. These outcomes differences remained despite adjustment for
hospital volume, the use of MIS, and MIS conversion to open surgery.
Conclusions We demonstrate evidence of racial disparities in the use of MIS for benign surgical conditions and worse outcomes for patients
of black race. Although, the racial differences in outcome were attenuated with adjustment for MIS, further studies are needed
to help resolve remaining differences in outcomes across race.
Presented at the 2008 SAGES Annual Meeting. 相似文献
94.
Background Gastric bypass surgery for morbid obesity has dramatically increased in volume over the past decade. Caucasian patients have
been noted previously to lose more weight after bariatric surgery than African-Americans patients. Data regarding predictors
of maintaining weight loss after surgery are minimal. We sought to determine predictors of long-term weight loss after bariatric
surgery.
Methods Retrospective analysis using a multivariate logistic regression model of all patients undergoing Roux-en-Y gastric bypass
surgery at the Medical University of South Carolina from May 1993 to December 2004 for whom 2 years of follow-up data was
available. Our dependent variable was the percentage of weight lost from baseline, dichotomized at ±35%. Our primary independent
variable was race, defined as Caucasian, African-American, or other. Relevant covariates were added to the model to control
for their potential effects on outcome.
Results One hundred eleven patients (17 male/94 female; 85% Caucasian, mean age 44 years (range 18–68 years). In our model, Caucasian
subjects (adjusted odds ratio [OR] = 7.60, 95% confidence intervals [95%CI] = 1.83–31.5) and late post surgical complications
(adjusted OR = 2.67, 95%CI = 1.05–6.80) significantly predicted weight loss at 2 years, after controlling for relevant confounders.
Other covariates did not significantly impact the model.
Conclusion Race and late post surgical complications significantly impacted the percentage of weight loss at 2 years for patients undergoing
Roux-en-Y gastric bypass surgery at our institution. Future research should be directed at determining potential genetic and/or
social reasons for these differences. 相似文献
95.
Zhan M Flaws JA Gallicchio L Tkaczuk K Lewis LM Royak-Schaler R 《Cancer Detection and Prevention》2007,31(5):384-390
Background: Tamoxifen (TAM) is a selective estrogen receptor modulator (SERM) that is widely used as adjuvant therapy in breast cancer patients; however, it is also associated with undesirable side effects. The goal of this study was to investigate TAM-related side effects, and determine profiles of side effects by race and by smoking status. Methods: A secondary data analysis was conducted using cross-sectional study data from 138 African American and Caucasian women with breast cancer taking TAM 20 mg daily for at least 30 days prior to enrollment. Participants completed questionnaires that obtained information about demographic characteristics, reproductive history, health and lifestyle characteristics, TAM use and its related side effects. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals. Results: Compared to never smokers, a significantly greater percentage of current smokers reported ever experiencing TAM-related nausea (28.0% versus 5.0%, P = 0.007), depression (40.0% versus 7.1%, P = 0.001) and migraines (19.2% versus 1.7%, P = 0.02). These differences remained statistically significant after controlling for race, age, obesity, tumor stage, and duration of TAM treatment. No significant differences by race were noted in women reporting TAM side effects. Conclusion: The findings from this study suggest that current smokers with breast cancer should be informed of the increased probability of reporting TAM-related side effects such as nausea, depression and migraines, and counseled about smoking cessation which may reduce the incidence of these side effects. 相似文献
96.
97.
T. G. Travison T. J. Beck G. R. Esche A. B. Araujo J. B. McKinlay 《Osteoporosis international》2008,19(3):277-287
Summary Data on bone architecture in diverse male populations are limited. We examined proximal femur geometry in 1,190 black, Hispanic,
and white men. Cross-sectional analyses indicate greatest bone strength among black men, and greater age-related differences
in bone strength among Hispanic men than other subjects at the narrow neck and intertrochanter regions of the proximal femur.
Introduction Although race/ethnic differences in bone mass are well-documented, less is known about differences in bone architecture. We
examined proximal femur geometry in a diverse, randomly-sampled population of 1,190 community-dwelling men (age 30–79 y).
Methods Dual X-ray absorptiometry scans were obtained for 355 black, 394 Hispanic, and 441 white subjects. Measures were obtained
for the narrow neck (NN), intertrochanter (IT) and shaft regions of the proximal femur via hip structural analysis. Analyses
considered bone mineral density (BMD, g/cm2), outer diameter (cm), cross-sectional area (CSA, cm2), section modulus (Z, cm3), and buckling ratio (BR). Results were adjusted for height, weight and physical activity level.
Results Black subjects exhibited greater age-specific BMD, CSA and Z, than their white counterparts. For instance, at age 50 y, NN
BMD was approximately 11% higher among black men (p < 0.001). Hispanic men exhibited sharper age-related differences in NN and IT BMD than did others. IT BMD, for instance,
decreased by 2.4% with 10 y age among Hispanic subjects, but had virtually no age trend in others (p < 0.001).
Conclusions These results imply greater bone strength among black American men than among their white counterparts, and may indicate elevated
fracture risk among older Hispanic American subpopulations.
Grant support: The BACH/Bone study was supported by grant AG 20727 from the National Institute on Aging (NIA). The parent
study (BACH) was supported by grant DK 56842 from the National Institute of Diabetes and Digestive and Kidney Diseases. 相似文献
98.
Hand Movement Speed and Accuracy in Detoxified Alcoholics 总被引:1,自引:0,他引:1
Detoxified alcoholics (n = 192) were found to be 9.3% slower than age-matched controls (n = 112) with regard to the composite speed (movement time, MT) with which they were able to strike targets of various sizes and distances with a hand-held stylus at onset of a light stimulus (Fitts's Task). Females (n = 102) were 8% slower than males (n = 202), and blacks (n = 103) about 15.6% slower than whites (n = 201). Gender was the only significant factor with regard to errors (target misses), with women committing 28% fewer errors than men. Women, in contrast to men, appear to trade speed for accuracy in this task. Favorable socioeconomic/medical status and target misses were directly related to movement speed. Thus, when the MT data were corrected for lifestyle variables, the significance of the alcohol effects on MT disappeared, but gender differences persisted. The alcohol effect became statistically significant, the ethnic group differences remained statistically significant, and the gender effect became insignificant when MT scores were corrected for accuracy of performance (target misses). The slope of the linear function relating MT to target difficulty was similar for all subgroups. Prior knowledge of the direction of movement was found to affect MT performance more in white than in black subjects. With regard to reaction times, ethnic group and alcohol use effects remained statistically significant after corrections for lifestyle and errors were made, with values for blacks about 5% slower than values for whites, and values for alcoholics about 4.6% slower than those for controls. Prior knowledge of the direction of movement significantly improved (shortened) reaction time in all subgroups (14%-19%). 相似文献
99.
H. A. Bischoff-Ferrari J. E. Orav J. A. Barrett J. A. Baron 《Osteoporosis international》2007,18(9):1225-1233
Summary In this large population-based study, fracture rates for hips, distal forearms, proximal humeri, and ankles were higher in
winter than in other seasons, although the winter peak was small for hip fractures (p < 0.05 at all sites). Younger age between
65 and 80, living in warmer states and male gender were associated with increased winter morbidity due to fractures.
Introduction The objective was to investigate seasonal variation in the incidence of four common fractures, and explore the association
of weather with risk.
Methods Population-based analysis of individuals age 65 and older, including fractures of the hip, the distal forearm, the proximal
humerus and the ankle. Weather information was obtained from the US National Oceanic and Atmospheric Administration website.
Results For all fractures, rates were highest in winter and lowest in summer (p < 0.05 at all sites). Winter peaks were more pronounced
in warm climate states, in men, and in those younger than 80 years old. In winter, total snowfall was associated with a reduced
risk of hip fracture (−5% per 20 inches) but an increased risk of non-hip fractures (6–12%; p < 0.05 at all sites). In summer,
hip fracture risk tended to be lower during sunny weather (− 3% per 2 weeks of sunny days; p = 0.13), while other fractures
were increased (15%–20%; p < 0.05) in sunny weather.
Conclusion Fractures contribute considerably to winter morbidity in older individuals. Younger age between 65 and 80, living in warmer
states and male gender are risk factors for increased winter morbidity due to fractures. Weather affects hip fracture risk
differently than the other fractures studied.
Funding Supported by fellowships from the Harvard Hartford Foundation, from the Swiss Foundation for Nutrition Research, and the International
Foundation for the Promotion of Nutrition Research and Nutrition Education. 相似文献
100.