全文获取类型
收费全文 | 6238篇 |
免费 | 465篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 123篇 |
妇产科学 | 96篇 |
基础医学 | 1158篇 |
口腔科学 | 137篇 |
临床医学 | 554篇 |
内科学 | 1260篇 |
皮肤病学 | 200篇 |
神经病学 | 707篇 |
特种医学 | 230篇 |
外科学 | 513篇 |
综合类 | 12篇 |
一般理论 | 6篇 |
预防医学 | 595篇 |
眼科学 | 136篇 |
药学 | 383篇 |
中国医学 | 16篇 |
肿瘤学 | 559篇 |
出版年
2024年 | 9篇 |
2023年 | 65篇 |
2022年 | 108篇 |
2021年 | 190篇 |
2020年 | 125篇 |
2019年 | 167篇 |
2018年 | 171篇 |
2017年 | 184篇 |
2016年 | 200篇 |
2015年 | 236篇 |
2014年 | 263篇 |
2013年 | 348篇 |
2012年 | 533篇 |
2011年 | 537篇 |
2010年 | 302篇 |
2009年 | 288篇 |
2008年 | 413篇 |
2007年 | 442篇 |
2006年 | 380篇 |
2005年 | 388篇 |
2004年 | 316篇 |
2003年 | 308篇 |
2002年 | 250篇 |
2001年 | 58篇 |
2000年 | 48篇 |
1999年 | 51篇 |
1998年 | 44篇 |
1997年 | 43篇 |
1996年 | 22篇 |
1995年 | 23篇 |
1994年 | 29篇 |
1993年 | 18篇 |
1992年 | 28篇 |
1991年 | 17篇 |
1990年 | 12篇 |
1989年 | 14篇 |
1988年 | 5篇 |
1987年 | 13篇 |
1986年 | 9篇 |
1985年 | 5篇 |
1984年 | 5篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 7篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1978年 | 3篇 |
1977年 | 6篇 |
1973年 | 3篇 |
1968年 | 2篇 |
排序方式: 共有6719条查询结果,搜索用时 15 毫秒
991.
Pike KM Wilfley D Hilbert A Fairburn CG Dohm FA Striegel-Moore RH 《Psychiatry research》2006,142(1):19-29
The present study investigated the occurrence of life events preceding the onset of disturbed eating in binge-eating disorder (BED). In a case-control design, 162 matched pairs of black and white women with BED and women with no current psychiatric disorder, and 107 matched pairs of women with BED and a current general psychiatric disorder were recruited from the community for the New England Women's Health Project. Life events in the year before the onset of disturbed eating were assessed retrospectively with an investigator-based interview. Women with BED reported exposure to a significantly greater number of life events during the year before onset of eating disturbances than both the non-psychiatric and psychiatric control women during the same period of time in their lives. Women with BED had a significantly higher risk of exposure to certain specific life events (e.g., critical comments about shape, weight, or eating; stress related to work, school or other sources; major changes in life circumstances and relationships; physical abuse; and feeling unsafe in a variety of settings) than the non-psychiatric control women, while differences between the BED and the psychiatric control group were less marked. There was no evidence for race-specific exposure to antecedent life events. The results suggest that a greater number and certain specific types of life events increase risk for the subsequent development of BED. 相似文献
992.
993.
Puschner B Born A Giessler A Giebler A Helm H Leese M Bindman JP Gray RJ Schene A Kikkert M Burti L Marrella G Becker T 《The Journal of nervous and mental disease》2006,194(10):746-752
Quality of life is often severely impaired in people with schizophrenia, and adherence to antipsychotic medication has been consistently found to be low in this population. Although there is a considerable amount of evidence on these two variables in schizophrenia research, there is only limited knowledge on how they relate to one another. The aim of this study is to develop a meaningful model of the relationship between quality of life and adherence that includes mediating variables. A multicenter randomized controlled trial recruited 409 subjects in London, Verona, Amsterdam, and Leipzig. Baseline interviews obtained data on adherence, quality of life, and other variables. We used graphical modeling to investigate the relationships between the variables. No direct relation could be discerned between subjective quality of life and adherence to medication. Mediating variables, most importantly symptomatic impairment, global functioning, and medication side effects, were identified by the model. It can be concluded that, when aiming at the improvement of quality of life in people with schizophrenia, variables other than adherence, i.e., symptomatic impairment, global functioning, and medication side effects, should be targeted. 相似文献
994.
Anja Hansen Romain Géneaux Axel Günther Alexander Krüger Tammo Ripken 《Biomedical optics express》2013,4(6):852-867
In femtosecond laser ophthalmic surgery tissue dissection is achieved by photodisruption based on laser induced optical breakdown. In order to minimize collateral damage to the eye laser surgery systems should be optimized towards the lowest possible energy threshold for photodisruption. However, optical aberrations of the eye and the laser system distort the irradiance distribution from an ideal profile which causes a rise in breakdown threshold energy even if great care is taken to minimize the aberrations of the system during design and alignment. In this study we used a water chamber with an achromatic focusing lens and a scattering sample as eye model and determined breakdown threshold in single pulse plasma transmission loss measurements. Due to aberrations, the precise lower limit for breakdown threshold irradiance in water is still unknown. Here we show that the threshold energy can be substantially reduced when using adaptive optics to improve the irradiance distribution by spatial beam shaping. We found that for initial aberrations with a root-mean-square wave front error of only one third of the wavelength the threshold energy can still be reduced by a factor of three if the aberrations are corrected to the diffraction limit by adaptive optics. The transmitted pulse energy is reduced by 17% at twice the threshold. Furthermore, the gas bubble motions after breakdown for pulse trains at 5 kilohertz repetition rate show a more transverse direction in the corrected case compared to the more spherical distribution without correction. Our results demonstrate how both applied and transmitted pulse energy could be reduced during ophthalmic surgery when correcting for aberrations. As a consequence, the risk of retinal damage by transmitted energy and the extent of collateral damage to the focal volume could be minimized accordingly when using adaptive optics in fs-laser surgery.OCIS codes: (110.1080) Active or adaptive optics, (140.3440) Laser-induced breakdown, (140.3300) Laser beam shaping, (330.4460) Ophthalmic optics and devices, (170.4470) Ophthalmology, (330.3350) Vision - laser damage 相似文献
995.
996.
997.
Bialek R Binder N Dietz K Joachim A Knobloch J Zelck UE 《Diagnostic microbiology and infectious disease》2002,43(4):283-288
To optimize routine screening for cryptosporidiosis, 198 stool samples from patients at risk and from calves were examined by enzyme immunoassay (EIA), a direct fluorescent-antibody (DFA) and a modified immunofluorescence assay. Ninety-nine samples were positive in at least one assay, whereas 99 were negative in all three assays. Sensitivity of antigen EIA and DFA were similar (94%, 95% CI: 88-98%, and 91%, 95% CI: 84-95%). The modified immunofluorescence was significantly less sensitive (64%, 95% CI: 55-74%). 149 samples were also examined by two nested PCR assays targeting either the 18S rRNA or Cryptosporidium outer wall protein (COWP) gene. A PCR product was amplified from 86 out of 89 samples being positive in at least one other assay (sensitivity 97%, 95% CI: 91-99%). None was obtained from 60 samples negative in the three other assays. PCR assays did not increase the detection rate. Antigen EIA or DFA appear sufficient for routine Cryptosporidium screening of fecal samples. 相似文献
998.
Danko Milošević Branko Miše Ivan Habuš Marija Topalović-Grković Danica Batinić Anja Tea Golubić Daniel Turudić 《Central European Journal of Medicine》2013,8(3):354-357
During ceftriaxone treatment of subdural empyema caused by Streptococcus intermedius urinary and biliary stones were noticed. Increased levels of urinary calcium excretion were detected during ongoing treatment in comparison with 2 months check-up. There were no significant changes in the promoter/inhibitor urolithiasis parameters, oxalate, citrate, urate, cistine, glycosaminoglycans or their ratios. Urine saturation was calculated using EQUIL 2 computer programme (calcium oxalate, brushite) and it was normal. Probable trigger for the ceftriaxone/calcium hydroxy carbonate phosphate mixture of stones was a critical boost of solubility products caused by ceftriaxone treatment and phospnate urine content with a subsequent large-scale spontaneous precipitation of crystals. 相似文献
999.
1000.
Mühlfeld AS Segerer S Hudkins K Farr AG Bao L Kraus D Holers VM Quigg RJ Alpers CE 《Kidney international》2004,65(4):1214-1223
BACKGROUND: Mice overexpressing thymic stromal lymphopoietin (TSLP) develop mixed cryoglobulinemia with renal disease closely resembling human cryoglobulin-associated membranoproliferative glomerulonephritis (MPGN), including glomerular deposits of immunoglobulins and complement. We assessed the effect of complement inhibition through overexpression of Crry (complement receptor-1 related gene/protein Y), which blocks the classic and alternative pathway of complement activation through inhibition of the C3 convertase, in cryoglobulinemia-associated immune complex glomerulonephritis. METHODS: TSLP transgenic mice were crossbred with animals overexpressing Crry. Mice were sacrificed after 50 days (females) or 120 days (males), and kidneys, blood, and urine were collected from seven mice of each experimental group (wild type, Crry transgenic, TSLP transgenic, and Crry/TSLP doubly transgenic). RESULTS: TSLP/Crry doubly transgenic animals demonstrated expected serum levels of Crry. Renal involvement, both in TSLP transgenic and TSLP/Crry doubly transgenic animals, was characterized by glomerular matrix expansion, macrophage influx, activation of mesangial cells, and deposition of immunoglobulins and complement. Overexpression of Crry did not result in significant improvement of renal pathology or laboratory findings. Expression of recombinant soluble Crry was confirmed by enzyme-linked immunosorbent assay (ELISA) in Crry transgenic animals. However, formation of the membrane attack complex C5b-9 as a marker of terminal active complement components and represented by glomerular C9 staining could not be inhibited in Crry transgenic TSLP mice. CONCLUSION: These results indicate that overexpression of Crry was not sufficient to prevent renal injury in TSLP transgenic mice. We suggest that the inhibitory capacity of Crry may be overwhelmed by chronic complement activation. Further studies need to address the role of complement in cryoglobulinemic glomerulonephritis before therapeutic complement inhibition can be attempted. 相似文献