全文获取类型
收费全文 | 2375篇 |
免费 | 175篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 81篇 |
妇产科学 | 77篇 |
基础医学 | 263篇 |
口腔科学 | 62篇 |
临床医学 | 297篇 |
内科学 | 520篇 |
皮肤病学 | 30篇 |
神经病学 | 127篇 |
特种医学 | 223篇 |
外科学 | 324篇 |
综合类 | 43篇 |
一般理论 | 2篇 |
预防医学 | 195篇 |
眼科学 | 42篇 |
药学 | 147篇 |
肿瘤学 | 106篇 |
出版年
2021年 | 28篇 |
2020年 | 17篇 |
2019年 | 23篇 |
2018年 | 28篇 |
2017年 | 16篇 |
2015年 | 31篇 |
2014年 | 34篇 |
2013年 | 51篇 |
2012年 | 74篇 |
2011年 | 90篇 |
2010年 | 65篇 |
2009年 | 61篇 |
2008年 | 78篇 |
2007年 | 106篇 |
2006年 | 87篇 |
2005年 | 82篇 |
2004年 | 76篇 |
2003年 | 75篇 |
2002年 | 69篇 |
2001年 | 67篇 |
2000年 | 81篇 |
1999年 | 75篇 |
1998年 | 69篇 |
1997年 | 52篇 |
1996年 | 51篇 |
1995年 | 44篇 |
1994年 | 28篇 |
1993年 | 38篇 |
1992年 | 65篇 |
1991年 | 61篇 |
1990年 | 67篇 |
1989年 | 56篇 |
1988年 | 61篇 |
1987年 | 60篇 |
1986年 | 59篇 |
1985年 | 60篇 |
1984年 | 37篇 |
1983年 | 37篇 |
1982年 | 41篇 |
1981年 | 26篇 |
1980年 | 25篇 |
1979年 | 29篇 |
1978年 | 23篇 |
1977年 | 19篇 |
1976年 | 21篇 |
1974年 | 14篇 |
1973年 | 17篇 |
1972年 | 21篇 |
1971年 | 14篇 |
1970年 | 18篇 |
排序方式: 共有2558条查询结果,搜索用时 15 毫秒
1.
2.
3.
B Gerdts AFPM Vloemans RW Kreis 《Journal of the European Academy of Dermatology and Venereology》2007,21(6):781-788
BACKGROUND: Toxic epidermal necrolysis (TEN) is a severe and potentially fatal drug reaction characterized by an extensive skin rash with blisters and exfoliation, frequently accompanied by mucositis. The wounds caused by TEN are similar to second-degree burns and severe cases may involve large areas of skin loss. OBJECTIVES: Analysis of our results in patients with TEN and evaluation of the variety of therapeutic interventions that has been studied and suggested in TEN. PATIENTS/METHODS: Retrospective analysis of 19 consecutive patients with TEN treated in our burns centre between 1989 and 2004. RESULTS: Immediate withdrawal of any potentially fatal drug, maximum supportive care, and a restricted and tailored antibiotic, medical and surgical treatment regimen confined mortality to 21%, whereas prognosis scores like APACHE II and SCORTEN predicted mortality of 22 and 30%, respectively. A positive contribution of selective digestive decontamination is suggested but has yet to be established. CONCLUSIONS: Because of a potentially fatal outcome, fast referral of a patient suspected of TEN to a specialized centre (mostly a burns unit or specialized dermatology centre) for expert wound management and tailored comprehensive care is strongly advised and contributes to survival. 相似文献
4.
1背景 育龄妇女常见慢性下腹痛,可造成身体损害、情绪忧伤及导致巨大的健康服务费用。美国在这方面的花费超过8亿8千万美元(Mathias 1996)。英国全国数据库的一般性诊治资料显示,慢性下腹痛发病率及流行率与偏头痛、背部痛、哮喘发病率相似(Zondervan 1999)。 相似文献
5.
Jan E. Zejda Thomas S. Hurst Ernest M. Barber Charles Rhodes James A. Dosman 《American journal of industrial medicine》1993,23(5):743-750
A cross-sectional survey on respiratory health in swine producers showed that 30% of 301 examined men usually used a dust mask when working inside a barn. They did not differ significantly from dust mask nonusers in respect to respiratory symptoms and lung function. This analysis was undertaken to determine whether the respiratory health of dust mask users was associated with reasons why they had started individual respiratory protection. The subjects were recontacted in order to identify those who started using a mask to deliberately prevent symptoms (42 men) and those who started protection because of pre-existing respiratory symptoms (44 men). Not unexpectedly, betweengroup comparisons of respiratory symptoms and lung function suggest that swine producers who wear dust masks for preventive purposes have better respiratory health than those who wear dust masks because of symptoms or those who do not use individual respiratory protection. The individual reasons for starting dust mask usage should be examined among potential determinants of the outcomes of prospective studies which can then provide more valid assessment of the effect of individual respiratory protection. © 1993 Wiley-Liss, Inc. 相似文献
6.
7.
Non-secretion of ABO blood group antigens as a host susceptibility factor in the spondyloarthropathies 总被引:1,自引:0,他引:1
R Shinebaum C C Blackwell P J Forster N P Hurst D M Weir G Nuki 《British medical journal (Clinical research ed.)》1987,294(6566):208-210
Gram negative bacteria precipitate reactive arthritis and may be concerned in the pathogenesis of ankylosing spondylitis and other spondyloarthropathies. Susceptibility to many infectious agents is associated with ABO blood group or secretor state, or both. The distribution of the ABO blood group or secretor state, or both, was therefore determined in 87 patients with ankylosing spondylitis and 32 with other forms of spondyloarthropathy. The prevalence of non-secretors was significantly increased in the total patient group (54/114; 47%) and in the subgroup with ankylosing spondylitis (41/84; 49%) compared with local controls (89/334; 27%) (p less than 0.001). Other subgroups of patients showed a similarly increased prevalence of non-secretion (33-47%). The distribution of ABO blood groups did not differ between patients and controls. The association between non-secretor state and ankylosing spondylitis strengthens the hypothesis that ankylosing spondylitis is a form of reactive arthritis. It also suggests several pathogenic mechanisms which may be relevant to the initial hostparasite interaction in ankylosing spondylitis. 相似文献
8.
Functional and structural characteristics of the glycosaminoglycans of the bladder luminal surface 总被引:7,自引:0,他引:7
The glycosaminoglycan layer of bladder has been proposed to play a crucial role in protecting the bladder from harmful substances in urine. Rats were partially cystectomized to determine whether bladder glycosaminoglycans are routinely eluted from the bladder surface in detectable quantities. Cystectomy produced no detectable qualitative or quantitative changes in excreted GAG thereby showing that most urinary glycosaminoglycan originates in the kidney and not from the bladder. Damaging the glycosaminoglycan layer by a dilute acid wash, however, leads to a consistent decrease in the output of urinary GAG which recovers to normal at the same rate as the layer regenerates. This suggests that the newly exposed sites tightly bind urinary GAG. We suggest that such binding may be a component of the normal physiological defense mechanism of the bladder. The bladder glycosaminoglycan layer was isolated, dilute acid being used to elute ionically-bound material and brief trypsinization to elute intercalated proteoglycans from the luminal surface. The GAG from the luminal surface, which was present at a density of one chain per 50 nm.2 of bladder surface, was quite different in composition from that isolated from the whole bladder. 相似文献
9.
10.
The authors describe their preliminary experience with the use of superparamagnetic magnetic resonance (MR) imaging contrast media for suppression of signal from flowing blood. The goal of this work was to determine if a superparamagnetic contrast agent could successfully eliminate blood signal during cardiac-gated MR imaging, thereby eliminating or reducing flow artifacts associated with the complex and variable hemodynamics within the heart chambers. Imaging and data analysis were performed in 17 dogs subjected to experimental myocardial infarction as part of a parallel project. Six doses (0.2, 1, 2, 3.5, 4, 5, and 10 mg/kg) of AMI-25, an experimental contrast agent, were used in the study. Spin-echo imaging was performed immediately before and every 5 minutes (for an average of 25 minutes) after bolus injection of the contrast agent. Variations in the image signal-to-noise ratio relative to a baseline (before injection of contrast agent) image were assessed as a function of dose and time. Preliminary results suggest that a considerable reduction in blood flow artifacts and, hence, increases in image signal-tonoise ratio can be achieved at doses greater than or equal to 3.5 mg/kg, for approximately 20 minutes after injection. Doses equal to or less than 2 mg/kg and images obtained more than 20 minutes after injection (regardless of dose) did not reliably show hemodynamic artifact suppression. 相似文献