全文获取类型
收费全文 | 991篇 |
免费 | 88篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 23篇 |
妇产科学 | 81篇 |
基础医学 | 141篇 |
口腔科学 | 58篇 |
临床医学 | 124篇 |
内科学 | 229篇 |
皮肤病学 | 4篇 |
神经病学 | 75篇 |
特种医学 | 66篇 |
外科学 | 77篇 |
综合类 | 13篇 |
一般理论 | 1篇 |
预防医学 | 60篇 |
眼科学 | 5篇 |
药学 | 77篇 |
肿瘤学 | 44篇 |
出版年
2023年 | 7篇 |
2022年 | 8篇 |
2021年 | 29篇 |
2020年 | 31篇 |
2019年 | 17篇 |
2018年 | 24篇 |
2017年 | 12篇 |
2016年 | 16篇 |
2015年 | 13篇 |
2014年 | 18篇 |
2013年 | 25篇 |
2012年 | 42篇 |
2011年 | 46篇 |
2010年 | 26篇 |
2009年 | 28篇 |
2008年 | 36篇 |
2007年 | 40篇 |
2006年 | 34篇 |
2005年 | 34篇 |
2004年 | 29篇 |
2003年 | 36篇 |
2002年 | 22篇 |
2001年 | 39篇 |
2000年 | 30篇 |
1999年 | 28篇 |
1998年 | 26篇 |
1997年 | 15篇 |
1996年 | 17篇 |
1995年 | 23篇 |
1994年 | 14篇 |
1993年 | 20篇 |
1992年 | 25篇 |
1991年 | 21篇 |
1990年 | 25篇 |
1989年 | 21篇 |
1988年 | 22篇 |
1987年 | 23篇 |
1986年 | 24篇 |
1985年 | 28篇 |
1984年 | 13篇 |
1983年 | 16篇 |
1982年 | 13篇 |
1981年 | 19篇 |
1980年 | 13篇 |
1979年 | 7篇 |
1978年 | 4篇 |
1977年 | 6篇 |
1975年 | 5篇 |
1973年 | 2篇 |
1936年 | 2篇 |
排序方式: 共有1082条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
BACKGROUND & AIMS: Nutrients and properties of lipases affect survival of lipolytic activity during aboral gastrointestinal transit. Whether different doses and formulations of bacterial lipase and diets affect steatorrhea was tested in pancreatic-insufficient dogs. METHODS: A dose of 0-600,000 IU of powdered and 135,000 and 300,000 IU of liquid bacterial lipase was given with a standard meal to 5 dogs with ligated pancreatic ducts. In 4 dogs, 0 or 300,000 IU (normal 6-hour postprandial amount) of powder bacterial lipase was also given with five meals containing 850 kcal with different nutrient caloric densities (mixture design). Coefficients of fat absorption during 72- hour fecal balance studies were used to assess treatments. RESULTS: With the standard meal, powder bacterial lipase reduced steatorrhea in a dose-dependent manner (P = 0.03), and 135,000 and 300,000 IU of the liquid form decreased steatorrhea more than powder bacterial lipase (P = 0.017 and 0.057, respectively). Coefficients of fat absorption with 300,000 IU of powder bacterial lipase correlated (r2 = 0.79; P < 0.001) with increasing proportions of fat calories in diets. CONCLUSIONS: Liquid bacterial lipase decreases steatorrhea more than powder, and 300,000 IU of powder bacterial lipase ingested with high-fat meals corrects canine pancreatic steatorrhea. The combination of adequate mixing of small amounts (milligrams) of bacterial lipase and high-fat meals abolishes canine steatorrhea and may abolish human pancreatic steatorrhea. (Gastroenterology 1997 Jun;112(6):2048-55) 相似文献
5.
A W Dombrowski G F Bills G Sabnis L R Koupal R Meyer J G Ondeyka R A Giacobbe R L Monaghan R B Lingham 《The Journal of antibiotics》1992,45(5):671-678
A novel cytochalasin, L-696,474, (18-dehydroxy cytochalasin H) that inhibits HIV-1 protease was discovered in fermentations of a bark-inhabiting Ascomycete, Hypoxylon fragiforme. The product was first identified from extracts of an agar medium. Fermentation studies on a number of media indicated that the product can be made on several solid and liquid media. Optimum production was obtained from growth in a complex medium composed of glycerol, glucose, citrate, Ardamine, soybean meal, tomato paste, and inorganic salts. Other Hypoxylon spp., related species of Xylariales, and other fungi known to produce cytochalasins, were also surveyed for their ability to make L-696,474. Only one other Hypoxylon fragiforme isolate was found to make this novel cytochalasin; none of the other cultures surveyed made L-696,474 or any other compounds which inhibit HIV-1 protease. 相似文献
6.
A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
7.
The neuroendocrine stress hormone norepinephrine augments Escherichia coli O157:H7-induced enteritis and adherence in a bovine ligated ileal loop model of infection 下载免费PDF全文
Vlisidou I Lyte M van Diemen PM Hawes P Monaghan P Wallis TS Stevens MP 《Infection and immunity》2004,72(9):5446-5451
The role of the neuroendocrine environment in the pathogenesis of enteric bacterial infections is increasingly being recognized. Here we report that norepinephrine augments Escherichia coli O157:H7-induced intestinal inflammatory and secretory responses as well as bacterial adherence to intestinal mucosa in a bovine ligated ileal loop model of infection. Norepinephrine modulation of enteritis and adherence was dependent on the ability of E. coli O157:H7 to form attaching and effacing lesions. 相似文献
8.
9.
David C. H. Benton Alan S. Monaghan Ramine Hosseini Parmvir K. Bahia Dennis G. Haylett Guy W. J. Moss 《The Journal of physiology》2003,553(1):13-19
The rat SK1 gene ( rSK1 ) does not form functional Ca2+ -activated potassium channels when expressed alone in mammalian cell lines. Using a selective antibody to the rSK1 subunit and a yellow fluorescent protein (YFP) tag we have discovered that rSK1 expression produces protein that remains largely at intracellular locations. We tested the idea that rSK1 may need an expression partner, rSK2, in order to form functional channels. When rSK1 was co-expressed with rSK2 in HEK 293 cells it increased the current magnitude by 77 ± 34 % (as compared with cells expressing rSK2 alone). Co-expression of rSK1 with rSK2 also changed the channel pharmacology. The sensitivity of SK current to block by apamin was reduced ~16-fold from an IC50 of 94 p m (for SK2 alone) to 1.4 n m (for SK2 and SK1 together). The sensitivity to block by UCL 1848 (a potent small molecule blocker of SK channels) was similarly reduced, ~26-fold, from an IC50 of 110 p m to 2.9 n m . These data clearly demonstrate that rSK1 and rSK2 subunits interact. The most likely explanation for this is that the subunits are able to form heteromeric assemblies. 相似文献
10.
D Raghavan E Heyderman P Monaghan J Gibbs E Ruoslahti M J Peckham A M Neville 《Journal of clinical pathology》1981,34(2):123-128
A xenograft line, HX 53, has been established in immune-suppressed mice from a specimen of a lymph node metastasis in a patient with a histological diagnosis of seminoma but with markedly raised circulating levels of alpha-fetoprotein. Histological, immunocytochemical, and ultrastructural studies of this xenograft line have suggested that a solid variant of yolk sac carcinoma may exist, which morphologically resembles seminoma, or that a continuum of differentiation exists between seminoma and yolk sac carcinoma. 相似文献