全文获取类型
收费全文 | 710篇 |
免费 | 57篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 38篇 |
妇产科学 | 12篇 |
基础医学 | 98篇 |
口腔科学 | 17篇 |
临床医学 | 69篇 |
内科学 | 158篇 |
皮肤病学 | 22篇 |
神经病学 | 19篇 |
特种医学 | 130篇 |
外科学 | 60篇 |
综合类 | 42篇 |
预防医学 | 32篇 |
眼科学 | 10篇 |
药学 | 28篇 |
肿瘤学 | 42篇 |
出版年
2022年 | 4篇 |
2021年 | 6篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 11篇 |
2017年 | 4篇 |
2016年 | 10篇 |
2015年 | 18篇 |
2014年 | 8篇 |
2013年 | 24篇 |
2012年 | 15篇 |
2011年 | 18篇 |
2010年 | 17篇 |
2009年 | 27篇 |
2008年 | 17篇 |
2007年 | 30篇 |
2006年 | 28篇 |
2005年 | 20篇 |
2004年 | 9篇 |
2003年 | 13篇 |
2002年 | 12篇 |
2001年 | 19篇 |
2000年 | 10篇 |
1999年 | 21篇 |
1998年 | 50篇 |
1997年 | 48篇 |
1996年 | 23篇 |
1995年 | 24篇 |
1994年 | 13篇 |
1993年 | 15篇 |
1992年 | 10篇 |
1991年 | 13篇 |
1990年 | 17篇 |
1989年 | 24篇 |
1988年 | 27篇 |
1987年 | 23篇 |
1986年 | 22篇 |
1985年 | 17篇 |
1984年 | 21篇 |
1983年 | 15篇 |
1982年 | 14篇 |
1981年 | 8篇 |
1980年 | 10篇 |
1979年 | 6篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 8篇 |
1973年 | 5篇 |
1972年 | 3篇 |
1966年 | 3篇 |
排序方式: 共有781条查询结果,搜索用时 15 毫秒
51.
NPY and Y receptors: lessons from transgenic and knockout models 总被引:1,自引:0,他引:1
Neuropeptide Y (NPY) in the central nervous system is a major regulator of food consumption and energy homeostasis. It also regulates blood pressure, induces anxiolysis, enhances memory retention, affects circadian rhythms and modulates hormone release. Five Y receptors (Y1, Y2, Y4, Y5 and Y6) are known to mediate the action of NPY and its two other family members, peptide YY (PYY) and pancreatic polypeptide (PP). Increased NPY signaling due to elevated NPY expression in the hypothalamus leads to the development of obesity and its related phenotypes, Type II diabetes and cardiovascular disease. Dysregulation in NPY signaling also causes alterations in bone formation, alcohol consumption and seizure susceptibility. The large number of Y receptors has made it difficult to delineate their individual contributions to these physiological processes. However, recent studies analysing NPY and Y receptor overexpressing and knockout models have started to unravel some of the different functions of these Y receptors. Particularly, the use of conditional knockout models has made it possible to pinpoint a specific function to an individual Y receptor in a particular location. 相似文献
52.
This study evaluates the effectiveness of graded physical exercise on self-efficacy and exercise tolerance among a group of cardiac patients (N = 43). These patients were aged from 41 years to 82 years (mean age = 63.5 years, SD = 10.0 years). Results of the study show that efficacy of physical activity was significantly associated with exercise tolerance. After a 3-month rehabilitation with graded physical exercise, both efficacy of activity and exercise tolerance were significantly enhanced. The enhancement was relatively independent of patients' gender, age, education, and diagnostic category. Limitations of the study are discussed and future research suggested. 相似文献
53.
We report our clinical experience with phototherapy in 3802 infants; 3629 were exposed to "standard" daylight phototherapy and 173 to "high-intensity" blue-light phototherapy. High-intensity blue-light phototherapy was twice as effective as standard daylight phototherapy in decreasing bilirubin concentrations. No failures occurred with high-intensity phototherapy compared with an overall failure rate of 1.84/1000 with daylight lamps; these cases were transferred to high-intensity phototherapy with prompt response. Rebound after cessation of phototherapy was greater in those exposed to high-intensity blue light with a significantly greater number requiring a second exposure. However, the incidence was still low. No third exposure was required in any infant. Nursing of infants under high-intensity blue light was more difficult and inconvenient as was clinical monitoring. The light also caused more stress on the nursing and medical personnel. However, the infants tolerated both types of phototherapy equally well. High-intensity blue-light phototherapy would seem to be the treatment of choice for infants with rapidly increasing or very high bilirubin levels, as well as in those not responding adequately to daylight phototherapy. 相似文献
54.
Christabel Enweronu-Laryea Kim E Dickson Sarah G Moxon Aline Simen-Kapeu Christabel Nyange Susan Niermeyer France Bégin Howard L Sobel Anne CC Lee Severin Ritter von Xylander Joy E Lawn 《BMC pregnancy and childbirth》2015,15(Z2):S4
Background
An estimated two-thirds of the world's 2.7 million newborn deaths could be prevented with quality care at birth and during the postnatal period. Basic Newborn Care (BNC) is part of the solution and includes hygienic birth and newborn care practices including cord care, thermal care, and early and exclusive breastfeeding. Timely provision of resuscitation if needed is also critical to newborn survival. This paper describes health system barriers to BNC and neonatal resuscitation and proposes solutions to scale up evidence-based strategies.Methods
The maternal and newborn bottleneck analysis tool was applied by 12 countries in Africa and Asia as part of the Every Newborn Action Plan process. Country workshops engaged technical experts to complete the survey tool, which is designed to synthesise and grade health system "bottlenecks" that hinder the scale up of maternal-newborn intervention packages. We used quantitative and qualitative methods to analyse the bottleneck data, combined with literature review, to present priority bottlenecks and actions relevant to different health system building blocks for BNC and neonatal resuscitation.Results
Eleven of the 12 countries provided grading data. Overall, bottlenecks were graded more severely for resuscitation. The most severely graded bottlenecks for BNC were health workforce (8 of 11 countries), health financing (9 out of 11) and service delivery (7 out of 9); and for neonatal resuscitation, workforce (9 out of 10), essential commodities (9 out of 10) and service delivery (8 out of 10). Country teams from Africa graded bottlenecks overall more severely. Improving workforce performance, availability of essential commodities, and well-integrated health service delivery were the key solutions proposed.Conclusions
BNC was perceived to have the least health system challenges among the seven maternal and newborn intervention packages assessed. Although neonatal resuscitation bottlenecks were graded more severe than for BNC, similarities particularly in the workforce and service delivery building blocks highlight the inextricable link between the two interventions and the need to equip birth attendants with requisite skills and commodities to assess and care for every newborn. Solutions highlighted by country teams include ensuring more investment to improve workforce performance and distribution, especially numbers of skilled birth attendants, incentives for placement in challenging settings, and skills-based training particularly for neonatal resuscitation.55.
56.
57.
Naoko?Kozuki Anne?CC?Lee Mariangela?F?Silveira Ayesha?Sania Joshua?P?Vogel Linda?Adair Fernando?Barros Laura?E?Caulfield Parul?Christian Wafaie?Fawzi Jean?Humphrey Lieven?Huybregts Aroonsri?Mongkolchati Robert?Ntozini David?Osrin Dominique?Roberfroid James?Tielsch Anjana?Vaidya Robert?E?Black Joanne?Katz Child Health Epidemiology Reference Group Small-for-Gestational-Age-Preterm Birth Working Group 《BMC public health》2013,13(Z3):S2
Background
Previous studies have reported on adverse neonatal outcomes associated with parity and maternal age. Many of these studies have relied on cross-sectional data, from which drawing causal inference is complex. We explore the associations between parity/maternal age and adverse neonatal outcomes using data from cohort studies conducted in low- and middle-income countries (LMIC).Methods
Data from 14 cohort studies were included. Parity (nulliparous, parity 1-2, parity ≥3) and maternal age (<18 years, 18-<35 years, ≥35 years) categories were matched with each other to create exposure categories, with those who are parity 1-2 and age 18-<35 years as the reference. Outcomes included small-for-gestational-age (SGA), preterm, neonatal and infant mortality. Adjusted odds ratios (aOR) were calculated per study and meta-analyzed.Results
Nulliparous, age <18 year women, compared with women who were parity 1-2 and age 18-<35 years had the highest odds of SGA (pooled adjusted OR: 1.80), preterm (pooled aOR: 1.52), neonatal mortality (pooled aOR: 2.07), and infant mortality (pooled aOR: 1.49). Increased odds were also noted for SGA and neonatal mortality for nulliparous/age 18-<35 years, preterm, neonatal, and infant mortality for parity ≥3/age 18-<35 years, and preterm and neonatal mortality for parity ≥3/≥35 years.Conclusions
Nulliparous women <18 years of age have the highest odds of adverse neonatal outcomes. Family planning has traditionally been the least successful in addressing young age as a risk factor; a renewed focus must be placed on finding effective interventions that delay age at first birth. Higher odds of adverse outcomes are also seen among parity ≥3 / age ≥35 mothers, suggesting that reproductive health interventions need to address the entirety of a woman’s reproductive period.Funding
Funding was provided by the Bill & Melinda Gates Foundation (810-2054) by a grant to the US Fund for UNICEF to support the activities of the Child Health Epidemiology Reference Group.58.
目的:观察妇科开腹手术患者术前给予依他昔布120mg对术后自控镇痛(PCA)吗啡用量的影响及其副作用。方法:随机选取全麻下接受妇科开腹全子宫(双附件)切除患者40例,术前分别给予安慰剂或依他昔布120mg口服。在手术后观察24h患者PCA吗啡用量,同时记录患者的疼痛评分和满意度评分,并观察不良反应。结果:术后PCA吗啡24h消耗量在依他昔布组为9.4±7.6mg,显著低于安慰剂组15.7±8.9mg。两组患者24h内对PCA的按压次数依他昔布组也低于安慰剂组(P<0.05)。其中术后3、6、8和12hPCA吗啡消耗量在两组间无显著差异。两组患者术后24h疼痛评分和对镇痛治疗的满意度也无差异。两组患者不良反应的发生率亦无差别。结论:在妇科开腹手术患者术前应用依他昔布120mg可使患者术后PCA吗啡消耗量降低,且在术后12h后下降明显。未发现与依他昔布应用相关的副作用。 相似文献
59.
Monisha E. Nongpiur Ching-Yu Cheng Roopam Duvesh Saravanan Vijayan Mani Baskaran Chiea-Chuen Khor John Allen Srinivasan Kavitha Rengaraj Venkatesh David Goh Rahat Husain Pui Yi Boey Desmond Quek Ching Lin Ho Tina T. Wong Shamira Perera Tien Yin Wong Subbiah R. Krishnadas Eranga N. Vithana 《Ophthalmology》2018,125(5):664-670
60.