全文获取类型
收费全文 | 57907篇 |
免费 | 3992篇 |
国内免费 | 224篇 |
专业分类
耳鼻咽喉 | 684篇 |
儿科学 | 1473篇 |
妇产科学 | 1085篇 |
基础医学 | 7255篇 |
口腔科学 | 979篇 |
临床医学 | 5592篇 |
内科学 | 11855篇 |
皮肤病学 | 711篇 |
神经病学 | 5557篇 |
特种医学 | 1964篇 |
外国民族医学 | 4篇 |
外科学 | 9793篇 |
综合类 | 815篇 |
现状与发展 | 1篇 |
一般理论 | 69篇 |
预防医学 | 5101篇 |
眼科学 | 1209篇 |
药学 | 3557篇 |
中国医学 | 62篇 |
肿瘤学 | 4357篇 |
出版年
2023年 | 220篇 |
2022年 | 423篇 |
2021年 | 996篇 |
2020年 | 558篇 |
2019年 | 948篇 |
2018年 | 1159篇 |
2017年 | 797篇 |
2016年 | 896篇 |
2015年 | 996篇 |
2014年 | 1646篇 |
2013年 | 2442篇 |
2012年 | 3586篇 |
2011年 | 3891篇 |
2010年 | 2196篇 |
2009年 | 2018篇 |
2008年 | 3506篇 |
2007年 | 3689篇 |
2006年 | 3656篇 |
2005年 | 3754篇 |
2004年 | 3683篇 |
2003年 | 3364篇 |
2002年 | 3300篇 |
2001年 | 480篇 |
2000年 | 365篇 |
1999年 | 572篇 |
1998年 | 751篇 |
1997年 | 635篇 |
1996年 | 575篇 |
1995年 | 540篇 |
1994年 | 483篇 |
1993年 | 440篇 |
1992年 | 366篇 |
1991年 | 370篇 |
1990年 | 298篇 |
1989年 | 306篇 |
1988年 | 287篇 |
1987年 | 274篇 |
1986年 | 256篇 |
1985年 | 306篇 |
1984年 | 468篇 |
1983年 | 400篇 |
1982年 | 524篇 |
1981年 | 509篇 |
1980年 | 495篇 |
1979年 | 252篇 |
1978年 | 293篇 |
1977年 | 286篇 |
1976年 | 222篇 |
1975年 | 221篇 |
1974年 | 237篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Charles Opondo Stephen Ntoburi John Wagai Jackline Wafula Aggrey Wasunna Fred Were Annah Wamae Santau Migiro Grace Irimu Mike English 《Tropical medicine & international health : TM & IH》2009,14(10):1165-1172
Objective To assess the availability of resources that support the provision of basic neonatal care in eight first‐referral level (district) hospitals in Kenya. Methods We selected two hospitals each from four of Kenya’s eight provinces with the aim of representing the diversity of this part of the health system in Kenya. We created a checklist of 53 indicator items necessary for providing essential basic care to newborns and assessed their availability at each of the eight hospitals by direct observation, and then compared our observations with the opinions of health workers providing care to newborns on recent availability for some items, using a self‐administered structured questionnaire. Results The hospitals surveyed were often unable to maintain a safe hygienic environment for patients and health care workers; staffing was insufficient and sometimes poorly organised to support the provision of care; some key equipment, laboratory tests, drugs and consumables were not available while patient management guidelines were missing in all sites. Conclusion Hospitals appear relatively poorly prepared to fill their proposed role in ensuring newborn survival. More effective interventions are needed to improve them to meet the special needs of this at‐risk group. 相似文献
22.
23.
24.
Charles D Phillips 《BMC health services research》2006,6(1):117-4
This commentary discusses the need for, and the advantages of, a more concise, revised definition of the field of health services
research. It argues for a definition that includes not only the topics on which health services research focuses but also
the goals of health services research. A number of condensed definitions are provided for consideration. 相似文献
25.
Mary C Tierney W Gary Snow Jocelyn Charles Rahim Moineddin Alex Kiss 《The American journal of geriatric psychiatry》2007,15(2):140-148
OBJECTIVE: The authors examined the accuracy of certain neuropsychological tests in the prediction of harm resulting from self-neglect in cognitively impaired seniors who lived alone. METHODS: The study included 130 participants, aged 65 and older, who scored less than 131 on the Dementia Rating Scale. Neuropsychological tests were administered at baseline, resulting in eight predictive scores. Informants and primary care physicians provided information about harm that occurred to the participants during the 18-month prospective follow up. An incident was defined as harmful if it occurred as the result of self-neglect or disorientation and resulted in physical injury or property loss or damage and required emergency interventions. Proportional hazard regression analysis was conducted to examine the predictive relationship between the eight neuropsychological tests and time to incident harm with age, sex, education, the Charlson Comorbidity Index, and the Mini-Mental State Examination included in the model as covariates. RESULTS: Twenty-seven participants experienced harm during the 18-month follow-up period. A proportional hazards model indicated that three neuropsychological tests, which measured recognition memory, executive functioning, and conceptualization, were independent risk factors for harm. CONCLUSIONS: These findings provide insight into why harm occurred in these cognitively impaired elders who lived alone. They also support the ecologic validity of these tests and suggest directions for the development of intervention strategies for harm prevention. 相似文献
26.
Despite evidence from previous unit recording, microstimulation, lesioning and anatomical studies, the functions of the midbrain periaqueductal gray (PAG) remain unclear. We attempted to clarify the function of the PAG by recording activity of PAG units along with laryngeal and respiratory electromyograms (EMG) during vocalization in awake monkeys. PAG units were classified with respect to vocalization on the basis of their discharge patterns as 'early burst', 'late burst', 'tonic-increase' and 'tonic-off', with the vast majority being of the early- and late-burst type. Early-burst cells were correlated most frequently with inspiratory muscles of the respiratory system and laryngeal abductor muscles. Late-burst cells were most clearly correlated with laryngeal adductor and expiratory respiratory muscles. Data from spike-triggered averaging and parametric correlations indicate that most cells are related to single muscles, but a significant number were related to functionally related groups of two or more muscles. The results suggest that the PAG determines qualitative aspects of vocalization by the multisynaptic action its cells have on laryngeal and respiratory motoneurons. 相似文献
27.
28.
Charles P. Mouton Rebecca J. Rodabough Susan L. D. Rovi Robert G. Brzyski David A. Katerndahl 《Annals of family medicine》2010,8(3):206-213
PURPOSE The purpose of this study was to examine the psychological effects of physical and verbal abuse in a cohort of older women.METHODS This observational cohort study was conducted at 40 clinical sites nationwide that are part of the Women’s Health Initiative (WHI) Observational Study. We surveyed 93,676 women aged 50 to 79 years using the mental health subscales and the combined mental component summary (MCS) score of the RAND Medical Outcomes Study 36-item instrument.RESULTS At baseline, women reporting exposure to physical abuse only, verbal abuse only, or both physical and verbal abuse had a greater number of depressive symptoms (1.6,1.6, and 3 more symptoms, respectively) and lower MCS scores (4.6, 5.4, and 8.1 lower scores, respectively) than women not reporting abuse. Compared with women who had no exposure to abuse, women had a greater increase in the number of depressive symptoms when they reported a 3-year incident exposure to physical abuse only (0.2; 95% confidence interval [CI], −0.21 to 0.60), verbal abuse only (0.18; 95% CI, 0.11 to 0.24), or both physical and verbal abuse (0.15; 95% CI, −0.05 to 0.36); and they had a decrease in MCS scores when they reported a 3-year incident exposure to physical abuse only (−1.12; 95% CI, −2.45 to 0.12), verbal abuse only (−0.55; 95% CI, −0.75 to −0.34), and both physical and verbal abuse (−0.44; 95% CI, −1.11 to −0.22) even after adjustment for sociodemographic characteristics.CONCLUSION Exposure to abuse in older, functionally independent women is associated with poorer mental health. The persistence of these findings suggests that clinicians need to consider abuse exposure in their older female patients who have depressive symptoms. Clinicians caring for older women should identify women at risk for physical and verbal abuse and intervene appropriately. 相似文献
29.
BACKGROUND: Previous studies with cystic fibrosis transmembrane conductance regulator (CFTR) DeltaF508 mice indicate that estrogen levels may play a role in the occurrence or severity of CF-associated liver disease. However, the underlying mechanisms of liver disease in CF are poorly understood. METHODS: The levels of SULT1E1 (estrogen sulfotransferase) were measured in livers of control and CFTR-knockout (KO) mice. The impact of increased SULT1E1 activity on hepatic protein expression was assessed by immunoblot and MALDI mass spectrometric analysis. RESULTS: SULT1E1 expression was significantly elevated in livers of several CFTR-KO mice. SULT1E1 and CFTR were specifically detected in hepatocytes and cholangiocytes, respectively. Elevated SULT1E1 activity may result in lower levels of free beta-estradiol thereby altering estrogen-responsive hepatic protein expression. Estrogen receptors (ER)-alpha and beta were differentially regulated in CFTR-KO and CFTR-DeltaF508 mice. ERalpha expression was reduced in mice with high SULT1E1 activity. Glutathione S-transferase-P1 and carbonic anhydrase III were significantly decreased in CFTR (-/-) mice with high SULT1E1 activity. Furthermore, cytochrome P450 2B9, also estrogen regulated, was significantly induced in the livers of CFTR (-/-) mice with high SULT1E1 activity. CONCLUSIONS: Elevated SULT1E1 levels and associated alterations in estrogen-regulated hepatic protein expression may play an important role in CF liver disease. 相似文献
30.