全文获取类型
收费全文 | 69584篇 |
免费 | 6217篇 |
国内免费 | 120篇 |
专业分类
耳鼻咽喉 | 798篇 |
儿科学 | 2130篇 |
妇产科学 | 1996篇 |
基础医学 | 9681篇 |
口腔科学 | 1488篇 |
临床医学 | 9766篇 |
内科学 | 12076篇 |
皮肤病学 | 904篇 |
神经病学 | 5975篇 |
特种医学 | 2402篇 |
外国民族医学 | 1篇 |
外科学 | 8027篇 |
综合类 | 1224篇 |
一般理论 | 72篇 |
预防医学 | 8665篇 |
眼科学 | 1299篇 |
药学 | 4834篇 |
2篇 | |
中国医学 | 75篇 |
肿瘤学 | 4506篇 |
出版年
2021年 | 1109篇 |
2020年 | 646篇 |
2019年 | 1106篇 |
2018年 | 1243篇 |
2017年 | 984篇 |
2016年 | 1009篇 |
2015年 | 1143篇 |
2014年 | 1563篇 |
2013年 | 2528篇 |
2012年 | 3663篇 |
2011年 | 3750篇 |
2010年 | 2023篇 |
2009年 | 1769篇 |
2008年 | 3377篇 |
2007年 | 3673篇 |
2006年 | 3545篇 |
2005年 | 3514篇 |
2004年 | 3328篇 |
2003年 | 3019篇 |
2002年 | 3042篇 |
2001年 | 1775篇 |
2000年 | 1844篇 |
1999年 | 1627篇 |
1998年 | 953篇 |
1997年 | 748篇 |
1996年 | 731篇 |
1995年 | 714篇 |
1994年 | 622篇 |
1993年 | 614篇 |
1992年 | 1369篇 |
1991年 | 1248篇 |
1990年 | 1263篇 |
1989年 | 1150篇 |
1988年 | 1093篇 |
1987年 | 1065篇 |
1986年 | 996篇 |
1985年 | 1003篇 |
1984年 | 823篇 |
1983年 | 721篇 |
1982年 | 610篇 |
1981年 | 519篇 |
1980年 | 532篇 |
1979年 | 721篇 |
1978年 | 599篇 |
1977年 | 470篇 |
1976年 | 474篇 |
1974年 | 524篇 |
1973年 | 526篇 |
1972年 | 494篇 |
1971年 | 457篇 |
排序方式: 共有10000条查询结果,搜索用时 333 毫秒
81.
82.
J.D. Schold T.R. Srinivas G. Guerra A.I. Reed R.J. Johnson I.D. Weiner R. Oberbauer J.S. Harman A.W. Hemming H.U. Meier-Kriesche 《American journal of transplantation》2007,7(3):550-559
Research suggests that end-stage renal disease patients with elevated body mass index (BMI) have superior outcomes on dialysis. In contrast, low and high BMI patients represent the highest risk cohorts for kidney transplant recipients. The important question remains concerning how to manage transplant candidates given the potentially incommensurate impact of BMI by treatment modality. We conducted a retrospective analysis of waitlisted and transplanted patients in the United States from 1990 to 2003. We constructed Cox models to evaluate the effect of BMI on mortality of waitlisted candidates and identified risk factors for rapid weight change. We then assessed the impact of weight change during waitlisting on transplant outcomes. Decline in BMI on the waiting list was not protective for posttransplant mortality or graft loss across BMI strata. Substantial weight loss pretransplantation was associated with rapid gain posttransplantation. The highest risk for death was among listed patients with low BMI (13-20 kg/m(2), adjusted hazard ratio = 1.47, p < 0.01). Approximately one-third of candidates had a change in BMI category prior to transplantation. While observed declines in BMI may be volitional or markers of disease processes, there is no evidence that candidates have improved transplant outcomes attributable to weight loss. Prospective trials are needed to evaluate the efficacy of weight loss protocols for candidates of kidney transplantation. 相似文献
83.
Gina Kearney MSN RN CS AHN-BC JeMe Cioppa-Mosca PT MBA Margaret G. E. Peterson Ph.D C. Ronald MacKenzie MD 《HSS journal》2007,3(2):198-201
In an outpatient rehabilitation setting, both patients’ use and therapists’ knowledge of complementary and alternative medicine
(CAM) varies widely. Based on this observation and a recognition of CAM as an emerging practice area for rehabilitation professionals,
it was felt that a thorough and consistent approach to the education and orientation of physical therapists to the world of
CAM and integrative care was needed. This special interest paper will describe one center’s approach, development, and use
of a unique and comprehensive training manual designed to provide both a structured and standardized approach for educating
physical therapists about CAM and related therapeutic modalities. This innovative teaching tool allows for multiple methods
of content delivery within a multidisciplinary format and can be used for those who practice currently or desire to practice
in an integrative care environment. 相似文献
84.
Ruth W Johnson Joan S Tilghman Lorrie R Davis-Dick Barbara Hamilton-Faison 《The ABNF journal》2006,17(2):60-62
The following article is an attempt to encapsulate an historical overview of spirituality in nursing. Despite a plethora of information relative to spirituality in nursing, the decision was to do an eclectic overview that was not reflective of any one spiritual/religious group. The authors at times found this goal difficult when writing about the Pre-Christian and Christian eras. Most of the major religions have their own perspective on the concept of spirituality, and historical personalities recorded maybe reflective of that particular religion. Another factor that impacted on the writing of this article was the concept that spirituality was not always linked specifically to religion. Spirituality was an experiential component of the wonders of nature and life, a domain that the authors took into account but did not expound upon. Finally the authors realized that spirituality has almost always been an aspect of African-American life and certainly of those in nursing. To this end the authors realize that there is a need for more research in this area. 相似文献
85.
Margaret MacDonald Matthew Law John Kaldor Jim Hales Gregory J. Dore 《The International journal on drug policy》2003,14(5-6):353
Objective: To examine the effectiveness of needle and syringe programmes (NSPs) in preventing HIV transmission among injecting drug users (IDUs).Methods: An ecological study design was used to determine change in HIV prevalence among injecting drug users between cities with and without NSPs. Several data sources, such as electronic journal databases, surveillance reports, websites, and index review of relevant journals, were used to identify studies of HIV seroprevalence among IDUs, and presence of NSPs. The rate of change in HIV prevalence was estimated by regression analysis.Results: There were 778 years of data from 99 cities globally included in the analysis. HIV prevalence decreased by 18.6% per annum in cities that introduce NSPs, and increased by 8.1% in cities that had never introduced NSPs (mean difference −24.7% [95% CI: −43.8, 0.5%], P=0.06). The mean difference was –33% when comparison was weighted to one over the variance of the regression estimator (29% decrease in cities with NSPs and 5% increase in cities without NSPs, P<0.001). When analysis was restricted to cities with first HIV seroprevalence less than 10%, the average annual change in seroprevalence was 18% lower in cities with NSPs (P=0.03).Conclusions: Despite the inherent limitations within an ecological study design, the study provides additional evidence that NSPs reduce transmission of HIV infection. The rapid spread of HIV among IDU populations and increasing rates of injecting in many countries calls for scaling up of NSPs as well as other harm reduction strategies. 相似文献
86.
87.
Barbara A. Laraia Author Vitae Judith B. BorjaAuthor Vitae Margaret E. BentleyAuthor Vitae 《Journal of the American Dietetic Association》2009,109(6):1042-1047
African Americans experience household food insecurity, ie, the limited availability of nutritionally adequate and safe food, or ability to acquire acceptable foods in socially acceptable ways, at three times the rate of non-Hispanic whites. Thirty percent of all African-American children live in food-insecure households. The purpose of this study was to identify characteristics associated with household food insecurity among a high-risk postpartum population. Two-hundred six low-income, African-American mother−infant dyads were recruited through the Special Supplemental Nutrition Program for Women, Infants, and Children clinics. The six-item US Department of Agriculture food security scale was used to classify households as food secure, marginally food secure, or food insecure. Multinomial logistic regression was used to estimate the association between selected maternal/household characteristics and household food-security status. Fifty-three percent of households were food secure, 34% were marginally food secure, and 13% were food insecure. Maternal education less than college (relative risk ratio [RRR]=0.46; 95% confidence interval [CI]: 0.22 to 0.98) was inversely associated with marginal food security. Depressive symptoms (RRR=1.09; 95% CI: 1.02 to 1.16) and having the baby's father in the household (RRR=3.46; 95% CI: 1.22 to 9.82) were associated with household food insecurity, while having a grandmother in the household (RRR=0.15; 95% CI: 0.03 to 0.80) was inversely associated with experiencing household food insecurity. Findings from this study suggest that young, low-income, African-American families with only one child are particularly susceptible to experiencing household food insecurity. Intergenerational support and transfer of knowledge can be a key protective attribute among low-income African-American households. 相似文献
88.
89.
90.