全文获取类型
收费全文 | 2738篇 |
免费 | 160篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 89篇 |
妇产科学 | 87篇 |
基础医学 | 314篇 |
口腔科学 | 49篇 |
临床医学 | 284篇 |
内科学 | 596篇 |
皮肤病学 | 28篇 |
神经病学 | 179篇 |
特种医学 | 170篇 |
外科学 | 335篇 |
综合类 | 44篇 |
一般理论 | 1篇 |
预防医学 | 219篇 |
眼科学 | 69篇 |
药学 | 193篇 |
中国医学 | 3篇 |
肿瘤学 | 239篇 |
出版年
2022年 | 27篇 |
2021年 | 48篇 |
2020年 | 24篇 |
2019年 | 21篇 |
2018年 | 43篇 |
2017年 | 29篇 |
2016年 | 44篇 |
2015年 | 45篇 |
2014年 | 78篇 |
2013年 | 88篇 |
2012年 | 145篇 |
2011年 | 131篇 |
2010年 | 86篇 |
2009年 | 85篇 |
2008年 | 122篇 |
2007年 | 110篇 |
2006年 | 106篇 |
2005年 | 94篇 |
2004年 | 93篇 |
2003年 | 84篇 |
2002年 | 78篇 |
2001年 | 68篇 |
2000年 | 68篇 |
1999年 | 67篇 |
1998年 | 43篇 |
1997年 | 45篇 |
1996年 | 38篇 |
1995年 | 38篇 |
1994年 | 25篇 |
1992年 | 48篇 |
1991年 | 56篇 |
1990年 | 42篇 |
1989年 | 48篇 |
1988年 | 58篇 |
1987年 | 53篇 |
1986年 | 54篇 |
1985年 | 56篇 |
1984年 | 29篇 |
1983年 | 30篇 |
1980年 | 21篇 |
1979年 | 40篇 |
1978年 | 32篇 |
1977年 | 23篇 |
1975年 | 22篇 |
1974年 | 27篇 |
1973年 | 34篇 |
1971年 | 30篇 |
1970年 | 20篇 |
1968年 | 22篇 |
1966年 | 21篇 |
排序方式: 共有2914条查询结果,搜索用时 15 毫秒
1.
Albert De Decker Rosalie Fergusson Benjamin Ondruschka Niels Hammer Johann Zwirner 《Clinical anatomy (New York, N.Y.)》2020,33(4):522-529
For 50 years now, sacrospinous ligament fixation (SSLF) has been used to treat pelvic organ prolapse consequent on altered integrity of the pelvic myofascial structures. It is usually performed vaginally, but it has recently been performed laparoscopically through either an anterior or a posterior approach, with the broad ligament as a landmark to differentiate the two. In the present study, these two laparoscopic approaches were assessed using Thiel-embalmed cadavers. The anterior and posterior approaches were compared in terms of the closest distance to anatomical structures at risk, including pelvic viscera, the obturator nerve, and vascular structures. The posterior approach was more often closer to the investigated vessels and the rectum. The obturator nerve and the ureter were close to both the anterior and posterior approaches. The urinary bladder was closer using the anterior approach. From an anatomical standpoint, therefore, the anterior laparoscopic approach for SSLF is more likely to cause injury to the urinary bladder, whereas the posterior approach is more prone to causing rectal and vessel injuries. This study illustrates, from a basic science perspective, the importance of combining fascia research, novel endoscopic or minimally invasive surgical exposures informed by anatomy, and contemporary trends in gynecology in order to improve patient outcomes. Clin. Anat. 33:522–529, 2020. © 2019 Wiley Periodicals, Inc. 相似文献
2.
Yew Kuang Cheng Paul A Decker Megan M O'Byrne Catherine R Weiler 《Annals of allergy, asthma & immunology》2006,97(3):306-311
BACKGROUND: There are limited studies of large cohorts of patients with specific polysaccharide antibody deficiency (SPAD) syndrome. OBJECTIVE: To study the clinical and laboratory characteristics of patients with specific polysaccharide antibody deficiency syndrome. METHODS: We retrospectively studied 75 patients with total IgG levels of at least 500 mg/dL and fewer than 9 of 12 responses to vaccination with pneumococcal vaccine polyvalent. Exclusion criteria included an IgG level less than 500 mg/dL, established immunodeficiency syndrome, and secondary immunodeficiency. RESULTS: The most common clinical presentation was frequent infections (n = 69; 92%), including sinusitis (n = 53; 77%), pneumonia (n = 29; 42%), ear infections (n = 18; 26%), and bronchitis (n = 19; 28%). Other presentations were systemic infections (n = 5; 7%), autoimmune or rheumatic diseases (n = 6; 8%), and chronic diarrhea (n = 4; 5%). The median IgG2 level of patients with no response to pneumococcal vaccine polyvalent tended to be lower than that of patients with at least 1 response (150 vs 193 mg/dL, respectively; P = .06). There was no association between total IgG level (categorized as 500-600 or > or = 600 mg/dL) and frequency of infection (P = .43). Patients with fewer responses to pneumococcal vaccine polyvalent and a higher frequency of infections were more likely to receive intravenous immunoglobulin (IVIG) therapy (P = .01 and .003, respectively). Treatment with IVIG significantly reduced the number of infections (P < .001). CONCLUSION: Patients with no response to pneumococcal vaccine polyvalent tended to have lower IgG2 levels; those with fewer responses were more likely to receive IVIG therapy. 相似文献
3.
4.
5.
R Sterner H Decker 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(11):4835-4839
The Bohr effect describes the usually negative coupling between the binding of oxygen and the binding of protons to respiratory proteins. It was first described for hemoglobin and provides for an optimal oxygen supply of the organism under changing physiological conditions. Our measurements of both oxygen and proton binding to the 24-meric tarantula hemocyanin establish the unusual case where a respiratory protein binds protons at low degrees of oxygenation but releases protons at high degrees of oxygenation. In contrast to what is observed with hemoglobin and other respiratory proteins, this phenomenon amounts to the inversion of the Bohr effect in the course of an oxygen-binding curve at a given pH value. Therefore, protons in spider blood can act either as allosteric activators or as allosteric inhibitors of oxygen binding, depending on the degree of oxygenation of hemocyanin. These functional properties of tarantula hemocyanin, which cannot be explained by classical allosteric models, require at least four different conformational states of the subunits. Inspection of the known x-ray structures of closely related hemocyanins suggests that salt bridges between completely conserved histidine and glutamate residues located at particular intersubunit interfaces are responsible for the observed phenomena. 相似文献
6.
Metabolic products of microorganisms. 255. Nikkomycins Wz and Wx, new chitin synthetase inhibitors from Streptomyces tendae 总被引:3,自引:0,他引:3
H Decker F Walz C Bormann H Z?hner H P Fiedler H Heitsch W A K?nig 《The Journal of antibiotics》1990,43(1):43-48
Two new dipeptidyl nikkomycins of the Z and X type were isolated from the culture broth of Streptomyces tendae TU 901/395-11/32 and characterized. They show a variation in the amino acid moiety of the molecule. Nikkomycin Wz is composed of L-tyrosine and 5-amino-5-deoxy-D-allo-furanuronic acid N-glycosidally bound to uracil, whereas nikkomycin Wx is composed of L-tyrosine and 5-amino-5-deoxy-D-allo-furanuronic acid N-glycosidally bound to 4-formyl-4-imidazolin-2-one. The new nikkomycins are good inhibitors of chitin synthetase from Coprinus cinereus but they did not inhibit growth of fungi and yeasts. 相似文献
7.
8.
In seven patients (mean age 22 years) with injuries of the pelvic ring, the rupture of the symphysis was treated by polydioxanone ligaments. Complete rupture of the ileosacral joint was treated twice by additional external fixation, twice a compression screw osteosynthesis was applied. Incomplete iliosacral rupture in another three cases was not operated. Patients were treated functionally without signs of loosening or instability. After a control examination after 5 months all patients were free of symptoms in the area of the symphysis. Infection of the operation area did not accur. In our opinion the advantages of this method are simple operative technique, reduced risk of infection and no need for removal of metallic implants. Our excellent initial experience with synthetic PDS ligaments in operative treatment of symphysis ruptur seem to justify its application for other injuries like iliosacral or acromioclavicular rupture. 相似文献
9.
Administration of either the muscarinic antagonist scopolamine or the benzodiazepine diazepam prior to training produced a dose-dependent impairment in the retention of one-trial inhibitory avoidance training in mice. To investigate the nature of this drug effect, the effects of scopolamine and diazepam were subsequently assessed on both acquisition and retention of inhibitory avoidance using a multiple-trial, training-to-criterion procedure. The training was conducted using either continuous trials in which the mouse was free to shuttle back and forth between shock and safe compartments or discrete trials in which the mouse was moved from the shock compartment of the safe compartment at the start of each trial. In either case, training continued until the mouse refrained from crossing into the shock compartment for a specified length of time on a single trial. Scopolamine (1.0 mg/kg) administered before training significantly increased the number of trials required to attain criterion, but did not affect retention when these mice were tested 2, 16, or 28 days later. In contrast, diazepam (1.0 mg/kg) did not significantly alter the number of trials necessary to reach criterion, but impaired retention of the inhibitory response in mice trained using discrete trials. The differences in the amnestic effects of scopolamine and diazepam revealed by this detailed analysis suggest that diazepam does not impair inhibitory avoidance performance through an effect on cholinergic function. 相似文献
10.