收费全文 | 88493篇 |
免费 | 8875篇 |
国内免费 | 2017篇 |
耳鼻咽喉 | 723篇 |
儿科学 | 1278篇 |
妇产科学 | 609篇 |
基础医学 | 5306篇 |
口腔科学 | 1359篇 |
临床医学 | 16994篇 |
内科学 | 10328篇 |
皮肤病学 | 470篇 |
神经病学 | 12201篇 |
特种医学 | 23274篇 |
外国民族医学 | 18篇 |
外科学 | 6862篇 |
综合类 | 8767篇 |
现状与发展 | 1篇 |
预防医学 | 2251篇 |
眼科学 | 1362篇 |
药学 | 2833篇 |
70篇 | |
中国医学 | 1092篇 |
肿瘤学 | 3587篇 |
2024年 | 362篇 |
2023年 | 1745篇 |
2022年 | 3281篇 |
2021年 | 4293篇 |
2020年 | 3953篇 |
2019年 | 3685篇 |
2018年 | 3471篇 |
2017年 | 3830篇 |
2016年 | 4034篇 |
2015年 | 3876篇 |
2014年 | 6448篇 |
2013年 | 5895篇 |
2012年 | 5273篇 |
2011年 | 5728篇 |
2010年 | 4698篇 |
2009年 | 4785篇 |
2008年 | 4681篇 |
2007年 | 4455篇 |
2006年 | 3909篇 |
2005年 | 3363篇 |
2004年 | 2897篇 |
2003年 | 2265篇 |
2002年 | 1835篇 |
2001年 | 1701篇 |
2000年 | 1385篇 |
1999年 | 1094篇 |
1998年 | 1118篇 |
1997年 | 1004篇 |
1996年 | 852篇 |
1995年 | 721篇 |
1994年 | 585篇 |
1993年 | 477篇 |
1992年 | 384篇 |
1991年 | 286篇 |
1990年 | 215篇 |
1989年 | 160篇 |
1988年 | 138篇 |
1987年 | 128篇 |
1986年 | 92篇 |
1985年 | 63篇 |
1984年 | 47篇 |
1983年 | 37篇 |
1982年 | 31篇 |
1981年 | 26篇 |
1980年 | 27篇 |
1979年 | 14篇 |
1978年 | 12篇 |
1977年 | 9篇 |
1976年 | 6篇 |
1974年 | 4篇 |
Context
Family caregivers constitute a critical component of the end-of-life care system with considerable cost to themselves. However, the joint association of terminally ill cancer patients' symptom distress and functional impairment with caregivers' subjective caregiving burden, quality of life (QOL), and depressive symptoms remains unknown.Objectives/Methods
We used multivariate hierarchical linear modeling to simultaneously evaluate associations between five distinct patterns of conjoint symptom distress and functional impairment (symptom-functional states) and subjective caregiving burden, QOL, and depressive symptoms in a convenience sample of 215 family caregiver–patient dyads. Data were collected every 2 to 4 weeks over patients' last 6 months.Results
Caregivers of patients in the worst symptom-functional states (States 3–5) reported worse subjective caregiving burden and depressive symptoms than those in the best two states, but the three outcomes did not differ between caregivers of patients in State 3 and States 4–5. Caregivers of patients in State 5 endured worse subjective caregiving burden and QOL than those in State 4. Caregivers of patients in State 4 suffered worse subjective caregiving burden and depressive symptoms but comparable QOL to those in State 2.Conclusion
Patients' five distinct, conjoint symptom-functional states were significantly and differentially associated with their caregivers' worse subjective caregiving burden, QOL, and depressive symptoms while caring for patients over their last 6 months. 相似文献Methods: [11C]WAY100635, [18F]altanserin and positron emission tomography were used to compare 5-HT1A and 5-HT2A binding in MDD patients divided into eight past suicide attempters (>4yrs prior to scanning) and eight lifetime non-attempters, and both groups were compared to eight healthy volunteers.
Results: The two receptor types differed in binding pattern across brain regions from each other, but there were no differences in binding between healthy volunteers and the two depressed groups or between depressed suicide attempters and non-attempters. No effects of depression severity or lifetime aggression were observed for either receptor.
Conclusion: Limitations of this study include small sample size and absence of high lethality suicide attempts in the depressed attempter group. No trait-like binding correlations with past suicide attempt or current depression were observed. Given the heterogeneity of nonfatal suicidal behavior, a larger sample study emphasizing higher lethality suicide attempts may find the serotonin biological phenotype seen in suicide decedents. 相似文献