全文获取类型
收费全文 | 787篇 |
免费 | 41篇 |
国内免费 | 96篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 37篇 |
妇产科学 | 2篇 |
基础医学 | 77篇 |
口腔科学 | 19篇 |
临床医学 | 127篇 |
内科学 | 157篇 |
皮肤病学 | 8篇 |
神经病学 | 27篇 |
特种医学 | 143篇 |
外科学 | 54篇 |
综合类 | 85篇 |
一般理论 | 1篇 |
预防医学 | 39篇 |
眼科学 | 4篇 |
药学 | 97篇 |
肿瘤学 | 43篇 |
出版年
2023年 | 4篇 |
2021年 | 9篇 |
2020年 | 4篇 |
2019年 | 10篇 |
2018年 | 5篇 |
2017年 | 4篇 |
2016年 | 9篇 |
2015年 | 8篇 |
2014年 | 13篇 |
2013年 | 24篇 |
2012年 | 26篇 |
2011年 | 16篇 |
2010年 | 33篇 |
2009年 | 35篇 |
2008年 | 21篇 |
2007年 | 64篇 |
2006年 | 23篇 |
2005年 | 31篇 |
2004年 | 8篇 |
2003年 | 9篇 |
2002年 | 9篇 |
2001年 | 21篇 |
2000年 | 18篇 |
1999年 | 14篇 |
1998年 | 42篇 |
1997年 | 42篇 |
1996年 | 33篇 |
1995年 | 32篇 |
1994年 | 28篇 |
1993年 | 39篇 |
1992年 | 15篇 |
1991年 | 12篇 |
1990年 | 17篇 |
1989年 | 32篇 |
1988年 | 29篇 |
1987年 | 20篇 |
1986年 | 17篇 |
1985年 | 16篇 |
1984年 | 14篇 |
1982年 | 10篇 |
1981年 | 4篇 |
1980年 | 13篇 |
1979年 | 4篇 |
1978年 | 8篇 |
1977年 | 9篇 |
1976年 | 5篇 |
1975年 | 4篇 |
1905年 | 3篇 |
1897年 | 3篇 |
1889年 | 3篇 |
排序方式: 共有924条查询结果,搜索用时 15 毫秒
41.
42.
43.
Nurses' perceived barriers to the implementation of a Fall Prevention Clinical Practice Guideline in Singapore hospitals 总被引:1,自引:0,他引:1
Serena SL Koh Elizabeth Manias Alison M Hutchinson Susan Donath Linda Johnston 《BMC health services research》2008,8(1):105
Background
Theories of behavior change indicate that an analysis of barriers to change is helpful when trying to influence professional practice. The aim of this study was to assess the perceived barriers to practice change by eliciting nurses' opinions with regard to barriers to, and facilitators of, implementation of a Fall Prevention clinical practice guideline in five acute care hospitals in Singapore. 相似文献44.
45.
T M de Chalain W L Michell S J O'Keefe J M Ogden 《The Journal of surgical research》1992,52(2):167-176
The ideal energy substrate for critically ill patients receiving total parenteral nutrition (TPN) remains controversial. While glucose has been proved to have nitrogen sparing properties in postoperative patients, critically ill patients tolerate glucose loads poorly and fat appears to be an obligatory fuel in sepsis. Furthermore, it is not yet certain whether the changes in whole body protein metabolism induced by critical illness are influenced by the nature of the TPN provided. This study was conducted on patients admitted to a surgical intensive care unit (SICU) who fulfilled the criteria of requiring TPN and mechanical ventilation for at least four days. Patients were randomized to receive either glucose (G) or equicaloric proportions of glucose and lipid (GF) as an intravenous energy source. TPN was commenced early, within 24-48 hr of trauma or surgery and admission to the ICU. Nonprotein calorie intake was 125% of calculated basal energy expenditure. Nitrogen balance was calculated from 24-hr urinary urea excretion. Protein synthesis, turnover, and catabolism were measured on Day 4 of the study using an established radiolabeled C14-leucine technique. Degree of sepsis and illness were calculated using published scores. Fifty patients entered the trial but 32 were excluded by Day 4. Of the 18 patients completing an initial four day study, eight went on to complete a second study on the alternative regimen--a total of 26 studies (14 G, 12 GF). Net protein synthesis was achieved in 18 studies (12 G, 6 FG) and positive nitrogen balance by Day 4 in 22 studies. Four patients on the G regimen were withdrawn due to glucose intolerance while none of the patients on GF developed glucose intolerance or hyperlipidaemia. Both whole body protein synthesis and catabolism correlated significantly with degree of sepsis. The type of TPN fuel used, G and GF, did not appear to influence whole body protein dynamics, both regimens achieving greatly improved whole body protein kinetics. 相似文献
46.
47.
48.
49.
An open-label, uncontrolled dose-optimization study of sublingual apomorphine in erectile dysfunction 总被引:1,自引:0,他引:1
Mulhall JP Bukofzer S Edmonds AL George M;Apomorphine SL Study Group 《Clinical therapeutics》2001,23(8):1260-1271
BACKGROUND: Because apomorphine is a dopamine agonist that acts on areas of the central nervous system believed to mediate penile erection, its use in erectile dysfunction (ED) has been investigated. However, it also produces nausea by dopamine-receptor stimulation of the chemotrigger zone in the brain. Therefore, a low plasma concentration, achieved rapidly, would be selective for the desired erectile response but would be below the dopamine threshold for nausea. OBJECTIVE: We evaluated the efficacy and tolerability of a dose-optimized regimen of a sublingual formulation of apomorphine (apomorphine SL) in the treatment of ED. METHODS: This was a multicenter, open-label, uncontrolled, Phase III dose-optimization study of apomorphine SL in heterosexual men with ED. The 2-week screening period, during which baseline severity of ED was determined using the International Index of Erectile Function, was followed by a 3-week dose-optimization period beginning at a dose of 2 mg. Patients were to make at least 2 attempts at intercourse per week throughout the study, placing 1 apomorphine tablet under the tongue beforehand. At the end of the first week, the dose could be increased to 3 mg at the discretion of the investigator; at the end of the second week, the dose could be increased to a maximum of 4 mg or decreased as needed. In the following 4-week treatment period, patients took their individual optimal doses. The primary efficacy variable was the percentage of attempts resulting in erections firm enough for intercourse, as assessed by investigators' review of data from patients' diaries. Secondary variables included the percentage of attempts resulting in successful intercourse, time to erection, and duration of erection. Information about adverse events, including their severity and relation to treatment, was determined on the basis of direct questioning, spontaneous reports, and review of patient diaries. RESULTS: The study enrolled 849 heterosexual men whose ages ranged from 31 to 78 years (mean, 58.1 years). They had a mean 5.7-year history of ED of varbus causes. ED was mild in 11.5% of the men, moderate in 23.8 c, and severe in 48.1%. When results of the last 8 attempts were pooled, representing the period during which patients were taking their optimal doses of apomorphine SL, the mean percentage of attempts resulting in erections firm enough for intercourse was 39.4%, compared with 13.1% at baseline; attempts resulting in intercourse increased from a mean of 12.7% at baseline to 38.3% with treatment. The average median time to erection was 23 minutes, and the average median duration of erection was 13 minutes. Nausea, the most common treatment-related adverse event (11.7%). was dose related and diminished with continued dosing. One patient had a single syncopal episode that was judged to be related to apomorphine SL. CONCLUSIONS: In the present study, a dose-optimization regimen of apomorphine SL-with dosing initiated at 2 mg and adjusted up to a maximum of 4 mg as needed-was effective and well tolerated in the treatment of ED, regardless of its cause or severity. 相似文献
50.
Background: An outbreak of food poisoning in a military establishment mess was investigated and remedial measures suggested. 相似文献