全文获取类型
收费全文 | 8086篇 |
免费 | 622篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 62篇 |
儿科学 | 279篇 |
妇产科学 | 263篇 |
基础医学 | 1009篇 |
口腔科学 | 127篇 |
临床医学 | 1138篇 |
内科学 | 1408篇 |
皮肤病学 | 127篇 |
神经病学 | 737篇 |
特种医学 | 190篇 |
外科学 | 812篇 |
综合类 | 61篇 |
一般理论 | 16篇 |
预防医学 | 1104篇 |
眼科学 | 114篇 |
药学 | 602篇 |
中国医学 | 13篇 |
肿瘤学 | 667篇 |
出版年
2024年 | 23篇 |
2023年 | 113篇 |
2022年 | 124篇 |
2021年 | 230篇 |
2020年 | 198篇 |
2019年 | 244篇 |
2018年 | 257篇 |
2017年 | 211篇 |
2016年 | 258篇 |
2015年 | 253篇 |
2014年 | 309篇 |
2013年 | 462篇 |
2012年 | 660篇 |
2011年 | 732篇 |
2010年 | 361篇 |
2009年 | 295篇 |
2008年 | 550篇 |
2007年 | 536篇 |
2006年 | 535篇 |
2005年 | 491篇 |
2004年 | 368篇 |
2003年 | 404篇 |
2002年 | 355篇 |
2001年 | 69篇 |
2000年 | 41篇 |
1999年 | 60篇 |
1998年 | 64篇 |
1997年 | 45篇 |
1996年 | 46篇 |
1995年 | 35篇 |
1994年 | 41篇 |
1993年 | 31篇 |
1992年 | 36篇 |
1991年 | 16篇 |
1990年 | 29篇 |
1989年 | 20篇 |
1988年 | 15篇 |
1987年 | 14篇 |
1986年 | 18篇 |
1984年 | 9篇 |
1983年 | 16篇 |
1982年 | 14篇 |
1981年 | 13篇 |
1980年 | 9篇 |
1979年 | 15篇 |
1978年 | 8篇 |
1977年 | 8篇 |
1975年 | 8篇 |
1974年 | 15篇 |
1973年 | 8篇 |
排序方式: 共有8729条查询结果,搜索用时 15 毫秒
21.
Guoping Lian Mark E Malone Jenny E Homan Ian T Norton 《Journal of controlled release》2004,98(1):139-155
This paper presents a mathematical model of in-mouth volatile release from gelled emulsion particles dispersed in a continuous aqueous phase. Data based on APCI MS-Breath analysis is presented to demonstrate the effect of particle size, oil content and oil-water partition coefficients. It is shown that in-mouth release of aroma from the dispersion of gelled emulsion particles follows a two-component kinetic equation with fast and slow components. Both the fast and slow rate constants depend on the particle size, oil content and oil water partition coefficient of the aroma. The relative amount of aroma contributing to the fast and slow components also depends on the size of the particles. In order to understand this unexpected behaviour, an analytical model was developed that considers the interplay between the mass transfer of flavour across the interface of the particles and that across the air-liquid interface. Analytical expressions for the two rate constants and the relative ratio of aroma contributing to the fast component have been derived. From this model, three regimes of in-mouth release of aroma from the dispersion of gelled emulsion particles were identified including, the emulsion regime, the transition regime and the gel particle regime. In the emulsion regime, changes in the size of gelled emulsion particles had negligible impact on the overall release. In the transition regime, the release was controlled by the interaction of flavour transfer from the particles with that across the air-water interface. In the gel particle regime, aroma release at long times was governed by the particles and that at short times was governed by the air-water interface, and the two processes were fully decoupled. A simple relationship was derived for the critical size above which the release of aroma from the dispersion of gelled emulsion particles is affected by the size of the particles. 相似文献
22.
E Anne Lacey R June Musgrave Jenny V Freeman Angela M Tod Peter Scott 《European Journal of Cardiovascular Nursing》2004,3(3):219-224
BACKGROUND: Psychological morbidity after an acute myocardial infarction (AMI) is known to be common, but can be addressed by appropriate rehabilitation. The area in which this research was conducted experiences high rates of deprivation and of coronary heart disease and limited access to hospital-based rehabilitation. Responding to concern about psychological needs of AMI patients, a self-help package was introduced and evaluated alongside standard hospital-based cardiac rehabilitation. AIMS: To evaluate the impact of a home-based self-help package (the Heart Manual), alongside existing cardiac rehabilitation provision, on psychological morbidity and health status after AMI. A secondary aim was to assess the suitability of the Heart Manual for older patients aged over 80 years. METHODS: A controlled observational study, comparing two cohorts of patients discharged from hospital after AMI. The intervention group was given the self-help package in addition to standard care. The control group received standard care alone. Outcome measures used were the Hospital Anxiety and Depression Scale and the EuroQol. RESULTS: The intervention group showed significant improvement in anxiety and depression scores after 3 months and nonsignificant improvement in general health status. Patients who attended hospital-based rehabilitation classes, and those aged over 80 years, also benefited from the intervention. CONCLUSION: A home-based self-help rehabilitation package is an effective tool alongside hospital-based rehabilitation classes and can be given to all age groups. 相似文献
23.
Shelley Allen Glenys Carlson Tamara Ownsworth Jenny Strong 《Australian Occupational Therapy Journal》2006,53(4):293-301
Aim: To present an evidence-based framework to improve the quality of occupational therapy expert opinions on work capacity for litigation, compensation and insurance purposes.
Methods: Grounded theory methodology was used to collect and analyse data from a sample of 31 participants, comprising 19 occupational therapists, 6 medical specialists and 6 lawyers. A focused semistructured interview was completed with each participant. In addition, 20 participants verified the key findings.
Results: The framework is contextualised within a medicolegal system requiring increasing expertise. The framework consists of (i) broad professional development strategies and principles, and (ii) specific strategies and principles for improving opinions through reporting and assessment practices.
Conclusions: The synthesis of the participants' recommendations provides systematic guidelines for improving occupational therapy expert opinion on work capacity. 相似文献
Methods: Grounded theory methodology was used to collect and analyse data from a sample of 31 participants, comprising 19 occupational therapists, 6 medical specialists and 6 lawyers. A focused semistructured interview was completed with each participant. In addition, 20 participants verified the key findings.
Results: The framework is contextualised within a medicolegal system requiring increasing expertise. The framework consists of (i) broad professional development strategies and principles, and (ii) specific strategies and principles for improving opinions through reporting and assessment practices.
Conclusions: The synthesis of the participants' recommendations provides systematic guidelines for improving occupational therapy expert opinion on work capacity. 相似文献
24.
This paper reports the prevalence of chronic esophagitis and nutritional status among 538 young persons aged 15 to 26 years from the high risk area for esophageal cancer. Of these subjects, 166 were from households with history of esophageal cancer and 372 were from households without history of esophageal cancer. The Incidences of chronic esophagltis among male and female adolescents were 37. 6% and 36% respectively, which was significantly higher than those in the low risk area (17%). The frequency of chronic esophagltis in the adolescents in the households with history of esophageal cancer was aiso higher than in those In the households without history of esophageal cancer. The deficiencies of vitamins, especially of riboflavin and ascorbate, are prevalent and severe among these adolescents. Ascorbate deficiency Is correlated with the severity of the chronic esophagltis. These results indicate that chronic esophagltis may be involved in the natural history of esophageal carclnogenesis. Nutrient defic 相似文献
25.
26.
27.
Abstract: The development of a teaching package for nurse educators on drug and alcohol problems is described and the contents of its 16 modules outlined. 相似文献
28.
29.
Zvi Laron Jenny Frenkel lrit Gil-Ad Beatrice Klinger Ernesto Lubin Patrick Wuthrich François Boutignon Vincent Lengerts Romano Deghenghi 《Clinical endocrinology》1994,41(4):539-541
OBJECTIVE Hexarelin is a new synthetic growth hormone releasing peptide. We have tested the efficacy of intranasal (i.n.) administration of hexarelin to stimulate plasma GH and have compared this to the intravenous (i.v.) administration of the peptide. PATIENTS Ten children with familial short stature (FSS) aged 5·5-15·5 years and two known GH deficient patients aged 24 and 28 years without GH treatment. METHODS All 12 subjects were submitted to i.v. (1 μg/kg) and i.n. (20 μg/kg) hexarelin tests with a one-week interval between tests. Blood samples for GH, TSH, fT4 and T3 were obtained at 0, 15, 30, 60, 90 and 120 minutes. The hormone determinations were made by standard radio-immunoassays (RIA). RESULTS Both the i.n. and i.v. administration of hexarelin induced a large GH response, the mean (±SD) being 72·2± 35·5 mU/l for the i.n. test and 79·6 ± 53·0 mU/l for the i.v. test. The peak GH in the i.v. test occurred at 15–30 minutes and in the i.n. test between 30 and 60 minutes. The GH deficient patients showed no GH response In either test. Plasma TSH decreased in the FSS children from a mean (±SD) of 1.0 ± 0·26 to 0·64±0 2 mU/l (P<0 005) during the i.n. test and from 1·0±0·3 to 0·7±0·3mU/l (P> 0 05) during the I.v. test. In the isolated GH deficient patient, plasma TSH decreased from 1·06±0·38 mU/l to 0·86±0·17 during the i.v. test and from 1·60±0·01 to 1·11±0·06mU/l during the i.n. test. There were no significant changes in plasma fT4 or T3 in any of the tests. CONCLUSIONS The synthetic hexapeptide hexarelin is a potent pituitary GH stimulator when administered intra-nasally. The GH response was similar to that observed after intravenous hexarelin. Simultaneously, there was a significant decrease in plasma TSH but the concentrations remained in the normal range. These findings appear to be of theoretical and practical relevance to the investigation and management of short children. 相似文献
30.
Jenny Weinstein BPhil BA Msc 《Health expectations》2006,9(2):98-109
OBJECTIVE: This study compares the process and outcomes of two approaches to engaging mental health (MH) service users in the quality assurance (QA) process. BACKGROUND: QA plays a significant role in health and care services, including those delivered in the voluntary sector. The importance of actively, rather than passively, involving service users in evaluation and service development has been increasingly recognized during the last decade. DESIGN: This retrospective small-scale study uses document analysis to compare two QA reviews of a MH Day Centre, one that took place in 1998 as a traditional inspection-type event and one that took place in 2000 as a collaborative process with a user-led QA agenda. Setting and participants The project was undertaken with staff, volunteers and service users in a voluntary sector MH Day Centre. Intervention The study compares the management, style, evaluation tools and service user responses for the two reviews; it considers staff perspectives and discusses the implications of a collaborative, user-led QA process for service development. RESULTS: The first traditional top-down inspection-type QA event had less ownership from service users and staff and served the main purpose of demonstrating that services met organizational standards. The second review, undertaken collaboratively with a user-led agenda focused on different priorities, evolving a new approach to seeking users' views and achieving a higher response rate. CONCLUSIONS: Because both users and staff had participated in most aspects of the second review they were more willing to work together and action plan to improve the service. It is suggested that the process contributed to an evolving ethos of more effective quality improvement and user involvement within the organization. 相似文献