全文获取类型
收费全文 | 572篇 |
免费 | 49篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 20篇 |
妇产科学 | 5篇 |
基础医学 | 127篇 |
口腔科学 | 16篇 |
临床医学 | 62篇 |
内科学 | 142篇 |
皮肤病学 | 12篇 |
神经病学 | 11篇 |
特种医学 | 101篇 |
外科学 | 45篇 |
综合类 | 30篇 |
预防医学 | 12篇 |
眼科学 | 4篇 |
药学 | 11篇 |
肿瘤学 | 22篇 |
出版年
2021年 | 5篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 10篇 |
2017年 | 9篇 |
2016年 | 5篇 |
2015年 | 15篇 |
2014年 | 11篇 |
2013年 | 13篇 |
2012年 | 9篇 |
2011年 | 18篇 |
2010年 | 23篇 |
2009年 | 17篇 |
2008年 | 16篇 |
2007年 | 20篇 |
2006年 | 25篇 |
2005年 | 10篇 |
2004年 | 28篇 |
2003年 | 8篇 |
2002年 | 6篇 |
2001年 | 11篇 |
2000年 | 10篇 |
1999年 | 12篇 |
1998年 | 27篇 |
1997年 | 27篇 |
1996年 | 37篇 |
1995年 | 19篇 |
1994年 | 15篇 |
1993年 | 19篇 |
1992年 | 6篇 |
1991年 | 9篇 |
1990年 | 9篇 |
1989年 | 16篇 |
1988年 | 20篇 |
1987年 | 16篇 |
1986年 | 16篇 |
1985年 | 15篇 |
1984年 | 10篇 |
1983年 | 15篇 |
1982年 | 10篇 |
1981年 | 14篇 |
1980年 | 7篇 |
1978年 | 5篇 |
1977年 | 7篇 |
1976年 | 7篇 |
1975年 | 4篇 |
1973年 | 2篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1928年 | 1篇 |
排序方式: 共有630条查询结果,搜索用时 15 毫秒
1.
2.
Repair of large midline incisional hernias with polypropylene mesh: Comparison of three operative techniques 总被引:9,自引:0,他引:9
de Vries Reilingh TS van Geldere D Langenhorst BLAM de Jong D van der Wilt GJ van Goor H Bleichrodt RP 《Hernia》2004,8(1):56-59
Polypropylene mesh is widely used for the reconstruction of incisional hernias that cannot be closed primarily. Several techniques have been advocated to implant the mesh. The objective of this study was to evaluate, retrospectively, early and late results of three different techniques, onlay, inlay, and underlay. The records of 53 consecutive patients with a large midline incisional hernia — 25 women and 28 men, mean age 60.4 (range 28–94) — were reviewed. Polypropylene mesh was implanted using the onlay technique in 13 patients, inlay in 23 patients, and underlay in 17 patients. Either the greater omentum or a polyglactin mesh was interponated between the mesh and the viscera. The records of these 53 patients were reviewed with respect to: size and cause of the hernia, pre- and postoperative mortality and morbidity, with special attention to wound complications. Patients were invited to attend the outpatient clinic at least 12 months after implantation of the mesh for physical examination of the abdominal wall. Postoperative complications occurred in 14 (26.4%) patients. The onlay technique had significantly more complications, as compared to both other techniques. Reherniation occurred in 15 (28.3%) patients. The reherniation rate of the inlay technique was significantly higher than after the underlay technique (44% vs 12%, P=0.03) and tended to be higher than the onlay technique (44% vs 23%, P=0.22). Repair of large midline incisional hernias with the use of a polypropylene mesh carries a high risk of complications and has a high reherniation rate. The underlay technique seems to be the better technique. 相似文献
3.
Nonheme iron in sickle erythrocyte membranes: association with phospholipids and potential role in lipid peroxidation 总被引:5,自引:0,他引:5
Previous studies documented the abnormal association of heme and heme proteins with the sickle RBC membrane. We have now examined RBC ghosts and inside-out membranes (IOM) for the presence of nonheme iron as detected by its formation of a colored complex with ferrozine. Sickle ghosts have 33.8 +/- 18.2 nmol nonheme iron/mg membrane protein, and sickle IOM have 4.3 +/- 3.0 nmol/mg. In contrast, normal RBC ghosts and IOM have no detectable nonheme iron. The combination of heme and nonheme iron in sickle IOM averages nine times the amount of membrane- associated iron in normal IOM. Kinetics of the ferrozine reaction show that some of this nonheme iron on IOM reacts slowly and is probably in the form of ferritin, but most (72% +/- 18%) reacts rapidly and is in the form of some other biologic chelate. The latter iron compartment is removed by deferoxamine and by treatment of IOM with phospholipase D, which suggests that it represents an abnormal association of iron with polar head groups of aminophospholipids. The biologic feasibility of such a chelate was demonstrated by using an admixture of iron with model liposomes. Even in the presence of tenfold excess adenosine diphosphate, iron partitions readily into phosphatidylserine liposomes; there is no detectable association with phosphatidylcholine liposomes. To examine the bioavailability of membrane iron, we admixed membranes and t-butylhydroperoxide and found that sickle membranes show a tenfold greater peroxidation response than do normal membranes. This is not due simply to a deficiency of vitamin E, and this is profoundly inhibited by deferoxamine. Thus, while thiol oxidation in sickle membranes previously was shown to correlate with heme iron, the present data suggest that lipid peroxidation is related to nonheme iron. In control studies, we did not find this pathologic association of nonferritin, nonheme iron with IOM prepared from sickle trait, high-reticulocyte, postsplenectomy, or iron-overloaded individuals. These data provide additional support for the concept that iron decompartmentalization is a characteristic of sickle RBCs. 相似文献
4.
5.
6.
7.
8.
Filarial Nematode Parasites Secrete a Homologue of the Human Cytokine Macrophage Migration Inhibitory Factor 总被引:12,自引:6,他引:12
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Diana V. Pastrana Nithyakalyani Raghavan Peter FitzGerald Stephen W. Eisinger Christine Metz Richard Bucala Robert P. Schleimer Carol Bickel Alan L. Scott 《Infection and immunity》1998,66(12):5955-5963
Filarial nematode parasites establish long-term chronic infections in the context of an antiparasite immunity that is strongly biased toward a Th2 response. The mechanisms that lead to this Th2 bias toward filarial antigens are not clear, but one possibility is that the parasites produce molecules that have the capacity to proactively modify their immunological environment. Here we report that filarial parasites of humans secrete a homologue of the human proinflammatory cytokine macrophage migration inhibitory factor (MIF) that has the capability of modifying the activity of human monocytes/macrophages. A cDNA clone isolated from a Brugia malayi infective-stage larva expression library encoded a 12.5-kDa protein product (Bm-MIF) with 42% identity to human and murine MIF. MIF homologues were also found to be expressed in the related filarial species Wuchereria bancrofti and Onchocerca volvulus. Bm-mif was transcribed by adult and larval parasites, and the protein product was found in somatic extracts and in the parasite’s excretory-secretory products. Immunohistocytochemistry revealed that Bm-MIF was localized to cells of the hypodermis/lateral chord, the uterine wall, and larvae developing in utero. Unexpectedly, the activities of recombinant Bm-MIF and human MIF on human monocytes/macrophages were found to be similar. When placed with monocytes/macrophages in a cell migration assay, Bm-MIF inhibited random migration. When placed away from cells, Bm-MIF induced an increase in monocyte/macrophage migration that was specifically inhibited by neutralizing anti-Bm-MIF antibodies. Bm-MIF is the first demonstration that helminth parasites produce cytokine homologues that have the potential to modify host immune responses to promote parasite survival. 相似文献
9.
10.
This study analyses the influence of female and male patient age and human
menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and
live birth rates with ovulation stimulation using HMG in combination with
intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI
treatment cycles in 184 patients carried out at a university fertility
centre were analysed in a retrospective fashion. The main outcomes measured
were clinical pregnancy rates and live birth rates. Increased female
partner age (> or = 35) and male partner age (> or = 40) were found
to negatively influence pregnancy rates with HMG/ IUI therapy. In addition,
this study demonstrated a critical threshold of HMG requirements beyond
which pregnancy did not occur. No pregnancies occurred in treatment cycles
requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular
maturity, irrespective of patient age. In conclusion, female partner age,
male partner age, and HMG requirements all significantly influence
pregnancy rates with HMG/IUI therapy.
相似文献