全文获取类型
收费全文 | 1985篇 |
免费 | 111篇 |
国内免费 | 113篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 81篇 |
妇产科学 | 16篇 |
基础医学 | 244篇 |
口腔科学 | 23篇 |
临床医学 | 229篇 |
内科学 | 523篇 |
皮肤病学 | 61篇 |
神经病学 | 145篇 |
特种医学 | 390篇 |
外国民族医学 | 2篇 |
外科学 | 96篇 |
综合类 | 44篇 |
预防医学 | 97篇 |
眼科学 | 24篇 |
药学 | 120篇 |
中国医学 | 2篇 |
肿瘤学 | 102篇 |
出版年
2021年 | 15篇 |
2020年 | 11篇 |
2019年 | 21篇 |
2018年 | 17篇 |
2016年 | 29篇 |
2015年 | 26篇 |
2014年 | 23篇 |
2013年 | 45篇 |
2012年 | 32篇 |
2011年 | 48篇 |
2010年 | 65篇 |
2009年 | 61篇 |
2008年 | 50篇 |
2007年 | 94篇 |
2006年 | 60篇 |
2005年 | 85篇 |
2004年 | 45篇 |
2003年 | 42篇 |
2002年 | 38篇 |
2001年 | 48篇 |
2000年 | 56篇 |
1999年 | 32篇 |
1998年 | 97篇 |
1997年 | 100篇 |
1996年 | 109篇 |
1995年 | 67篇 |
1994年 | 64篇 |
1993年 | 67篇 |
1992年 | 26篇 |
1991年 | 53篇 |
1990年 | 50篇 |
1989年 | 67篇 |
1988年 | 49篇 |
1987年 | 59篇 |
1986年 | 40篇 |
1985年 | 59篇 |
1984年 | 31篇 |
1983年 | 29篇 |
1982年 | 32篇 |
1981年 | 30篇 |
1980年 | 37篇 |
1979年 | 17篇 |
1978年 | 11篇 |
1977年 | 25篇 |
1976年 | 29篇 |
1975年 | 23篇 |
1974年 | 10篇 |
1972年 | 7篇 |
1970年 | 10篇 |
1965年 | 7篇 |
排序方式: 共有2209条查询结果,搜索用时 15 毫秒
1.
Gabi Mueller Claudio Perret Christina M Spengler 《Journal of rehabilitation medicine》2006,38(6):381-386
OBJECTIVE: Respiratory muscle endurance of able-bodied persons, assessed by normocapnic hyperpnoea at 70% of their maximal voluntary ventilation, usually ranges from 10 to 20 minutes. The aim of this study was to determine the level of ventilation that patients with paraplegia and tetraplegia can sustain for 10-20 minutes to later be used as the guideline for respiratory muscle endurance training. DESIGN: Pilot study; cross-over setting. SUBJECTS: Two groups, 8 patients with paraplegia and 6 with tetraplegia. METHODS: Respiratory muscle endurance tests were performed at 3 different intensities of normocapnic hyperpnoea, i.e. 20%, 40% and 60% maximal voluntary ventilation. Subjects performed partial re-breathing from a bag to assure normocapnia. Respiratory endurance was separately analysed for patients with paraplegia and tetraplegia. RESULTS: Mean respiratory endurance times were 46.0, 18.9 and 4.2 minutes at 20%, 40% and 60% maximal voluntary ventilation in patients with tetraplegia and 51.8, 38.8 and 12.2 minutes in patients with paraplegia. The duration differed significantly at 60% maximal voluntary ventilation between the groups. CONCLUSION: Minute ventilation to perform respiratory muscle endurance training can be set at around 40% of maximal voluntary ventilation for patients with tetraplegia and around 60% of maximal voluntary ventilation for patients with paraplegia, as these levels can be sustained for 10-20 minutes. 相似文献
2.
Summary— To investigate if the functional alterations observed in resistance arteries of spontaneously hypertensive rats (SHRs) were also present at the coronary level, in vitro experiments were performed in mesenteric resistance arteries (MRA) and in right (RIC) and left interventricular coronary (LIC) arteries taken from 15–25-week-old SHR and age-matched Wistar Kyoto rats WKYs. Using a passive extension protocol, internal diameters corresponding to 100 mmHg intraluminal pressure (D100) were determined and vessels were set up to a normalized internal diameter (0.9 D100). SHR mesenteric resistance arteries had a significantly smaller diameter compared to WKY arteries, whereas both types of SHR coronary arteries had a greater diameter compared to those of WKY rats. In arteries in the absence of contracting agonist, nitro-L-arginine (NOLA, 100 μM) induced a progressive rise in basal tone, which could be reversed by subsequent addition of L-arginine (100 μM) but not D-arginine (100 μM). When expressed as percent of maximal contractions induced by agonists (noradrenaline, NA [10 μM] in MRA; serotonin, 5-HT [10 μM], in RIC and LIC), these contractions were significantly stronger in WKY compared to SHR coronary and mesenteric resistance arteries. In NA-precontracted MRA and 5HT-precontracted coronary arteries in the presence of indomethacin (10 μM), the magnitude of acetylcholine-induced maximal relaxations (expressed as percent of maximal contractions induced by agonists) was greater in WKY compared to SHR arteries. After a 30-min incubation period, NOLA (100 μM) completely inhibited relaxations induced by acetylcholine (0.01–10 μM) in all types of precontracted arteries. Subsequent additions of sodium nitroprusside, (SNP, 10 μM) induced complete relaxations in all preparations. These results show that a basal release of NO or NO-like compound by endothelial cells is present in isolated mesenteric resistance and coronary arteries of WKY rats and SHRs. The contribution of endothelium-derived relaxing factor-nitric oxide (EDRF-NO) to arterial tone was lower in MRA compared to coronary arteries in both strains and in SHR compared to WKY arteries. In the SHR preparations, the impaired relaxation induced by acetylcholine appeared to be due to a functional alteration of the endothelium in the presence of normal reactivity of the smooth muscle cells. 相似文献
3.
4.
5.
表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
6.
7.
8.
G Gouzien J L Perret Y Lunven 《Revue de stomatologie et de chirurgie maxillo-faciale》1991,92(4):269-272
The authors reported here a case of dominant form of osteopetrosis. The patient was a 28 years old man hospitalized for a mandibular osteitis consecutive to a tooth extraction. The clinical examination detected a splenomegaly. The laboratory tests showed anemia and thrombopenia. A radiographic skeletal survey detected a typical generalized osteocondensation. The authors pointed out the radiologic signs of the disease and underscored the difficulties in managing osteomyelitis of the jaw in such patients. 相似文献
9.
Safety of Intravenous Immunoglobulin Preparations: A Prospective Multicenter Study to Exclude the Risk of Non-A, Non-B Hepatitis 总被引:1,自引:0,他引:1
Dr. P. Imbach B.A. Perret R. Babington K. Kaminski A. Morell and H.J. Heiniger 《Vox sanguinis》1991,61(4):240-243
The risk of non-A, non-B hepatitis transmission by an intravenous immunoglobulin (IVIG) preparation was assessed in a prospective multicenter trial in 68 patients with primary immunodeficiency disorders (40 children or adolescents and 28 adults). During the 4-week prestudy evaluation period the clinical examinations and liver function tests including alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transpeptidase, alkaline phosphatase, and bilirubin were normal in all patients. The treatment consisted of three infusions of 200 mg IVIG (pH 4; pepsin procedure) per kilogram body weight at 2-week intervals. During the observation period of 24 weeks following the first infusion of the study IVIG, the patients were monitored at regular time intervals. No clinical and laboratory signs of hepatitis or liver dysfunction were noticed. All patients completed the study. In 5 patients, one isolated alanine aminotransferase value and in another patient one gamma-glutamyl transpeptidase value were moderately elevated, but always below 2.5 times the upper limit of the reference range. Similar isolated and transient elevations were observed for aspartate aminotransferase and alkaline phosphatase. It was concluded that the IVIG preparation did not transmit non-A, non-B hepatitis or other viral liver diseases. 相似文献
10.