全文获取类型
收费全文 | 2067篇 |
免费 | 58篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 139篇 |
妇产科学 | 193篇 |
基础医学 | 148篇 |
口腔科学 | 98篇 |
临床医学 | 154篇 |
内科学 | 469篇 |
皮肤病学 | 22篇 |
神经病学 | 147篇 |
特种医学 | 35篇 |
外科学 | 434篇 |
综合类 | 15篇 |
一般理论 | 3篇 |
预防医学 | 51篇 |
眼科学 | 39篇 |
药学 | 83篇 |
中国医学 | 4篇 |
肿瘤学 | 82篇 |
出版年
2023年 | 8篇 |
2022年 | 23篇 |
2021年 | 29篇 |
2020年 | 27篇 |
2019年 | 24篇 |
2018年 | 32篇 |
2017年 | 27篇 |
2016年 | 48篇 |
2015年 | 68篇 |
2014年 | 97篇 |
2013年 | 120篇 |
2012年 | 156篇 |
2011年 | 150篇 |
2010年 | 93篇 |
2009年 | 98篇 |
2008年 | 132篇 |
2007年 | 149篇 |
2006年 | 156篇 |
2005年 | 151篇 |
2004年 | 124篇 |
2003年 | 99篇 |
2002年 | 87篇 |
2001年 | 45篇 |
2000年 | 35篇 |
1999年 | 32篇 |
1998年 | 21篇 |
1997年 | 3篇 |
1996年 | 8篇 |
1995年 | 5篇 |
1994年 | 7篇 |
1993年 | 9篇 |
1992年 | 9篇 |
1991年 | 18篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1982年 | 2篇 |
1980年 | 2篇 |
1976年 | 1篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1972年 | 3篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有2138条查询结果,搜索用时 15 毫秒
1.
2.
C Demiroglu A Ozder T Altug B Orbay S Satar-Yíldírím A Bilir G Deniz T Erbengi S Büyükdevrim 《Angiology》1991,42(4):323-330
The effects of n-3 fatty-acid supplementation on serum lipids, platelet aggregation, and the development of atherosclerotic lesions were studied in the cholesterol-fed rabbit. Serum total cholesterol and LDL cholesterol values were significantly reduced in comparison with those of the nonsupplemented cholesterol-fed group (p less than 0.005, p less than 0.0025, respectively), though still higher than those of the control group (p less than 0.0025, p less than 0.0125 respectively). Platelet aggregation was reduced below that of the cholesterol-fed and the control levels (p less than 0.0005, p less than 0.0025, respectively). The endothelial injury encountered in cholesterol-fed rabbits was inhibited in the supplemented group. It is concluded that n-3 fatty acids suppress atherogenesis in this animal model by interfering with platelet aggregation and lipid metabolism. 相似文献
3.
Both non swellable and swellable poly(EGDMA/HEMA) microbeads were produced by suspension copolymerization. These microbeads were modified by immobilization of a spacer-arm (hexamethylene diamine (HMDA)) and protein A. The optimal values for modifications were as follows: sodium periodate concentration, 1.0 mgml(-1); HMDA concentration, 4 mgml(-1); and glutaraldehyde concentration, 0.070 microgml(-1). Adsorption of protein A onto the plain and periodate oxidized poly(EGDMA/HEMA) microbeads were very close to each other, and were 0.01-0.02 mg protein A on the 1-g Microbeads I and II, respectively. Protein A immobilization on poly(EGDMA/HEMA) microbeads were studied at different temperatures, times, and pHs using single protein solution containing different amounts of proteins. The optimal values for immobilization were as follows: the initial protein A concentration, 0.1 mgml(-1); temperature, 25 degrees C; pH, 9.5; and immobilization time, 120 min. Incorporation of protein A resulted in 1.420 and 1.825 mg protein A on the 1-g Microbeads I and II, respectively. HIgG adsorption capacity on the protein A-incorporated poly(EGDMA/HEMA) microbeads is 27 and 35 mg HIgGg(-1) polymer for Microbeads I and II, respectively. 相似文献
4.
A Serda Kantarcio?lu Teun Boekhout G Sybren De Hoog Bart Theelen Ayhan Yücel Tuba R Ekmekci Bettina C Fries Reiko Ikeda Adem Koslu Kemal Altas 《Medical mycology》2007,45(2):173-181
Environmental fungi, in particular primary pathogens and Cryptococcus spp. can be responsible for skin lesions mimicking sporotrichosis. In this paper, we report a case of subcutaneous cryptococcosis in an apparently healthy, young male patient due to a non-C. neoformans Cryptococcus species, C. diffluens. The isolate showed in vitro phenotypic switching that may affect virulence and host inflammatory and immune responses, and in vitro resistance to amphotericin B and 5-flucytosin. This species shares several phenotypic traits with C. neoformans, and, therefore, decisive diagnosis should be based on biopsy and culturing results followed by molecular identification. 相似文献
5.
6.
Numerical chromosomal aberrations in prostate cancer: correlation with morphology and cell kinetics 总被引:3,自引:0,他引:3
Rolf -Peter Henke Eva Krüger Nebahat Ayhan Dirk Hübner Peter Hammerer 《Virchows Archiv : an international journal of pathology》1993,422(1):61-66
Eleven routinely processed radical prostatectomy specimens were studied for the presence of numerical chromosomal aberrations by means of in situ hybridization with nucleic acid probes specific for chromosomes 7, 10, 17, X, and Y. Cytogenetic information was correlated with morphology, tumour stage and volume as well as with cell kinetics, the latter being assessed by immunohistochemistry with antibodies raised against the proliferative cell nuclear antigen (PCNA) and against a formalin-resistant epitope of the Ki-67 antigen, MIB 1. In 5 of 11 cases, numerical aberrations of at least one chromosome were found. The cases with normal chromosome numbers were those with the smallest volumes of Gleason grade 4 and/or 5 tumour (mean 0.5 cm3) and represented tumours restricted to the prostate. Tumours with aberrations in the number of detected chromosomes showed advanced stages and large volumes of high-grade tumour (mean 12.5 cm3). All 4 tumours with positive surgical margins were recruited from a group with marked local heterogeneity in chromosome numbers. Immunostaining with MIB 1 and PCNA was most intense in areas of high-grade tumour and was positively correlated with the emergence of chromosomal aberrations. The data suggest that the appearance of numerical chromosomal aberrations in prostate cancer coincides with aggressive tumour behaviour and could be used as an additional prognostic marker.This work is part of E.K.'s doctoral thesis 相似文献
7.
OBJECTIVE: Autophagy is a form of physiological programmed cell death which is observable after hormonal withdrawal. In this study, the FM3A murine breast tumor cell line was treated with epirubicin alone and with medroxyprogesterone acetate (MPA) or tamoxifen, to determine if structural and kinetic signs of autophagy may also occur in an enhanced manner during epirubicin sensitization via hormonal agents. METHODS: One-week soft agar colony growth, 96-hour values of plating and pulse thymidine labeling and electron microscopical examinations were performed following treatment with MPA and tamoxifen alone or with epirubicin. RESULTS: Tamoxifen induced signs of autophagy, which was enhanced when it was combined with MPA. Epirubicin also induced autophagy of secretory granules, which coalesced to form an intracytoplasmic lumen. Combining MPA with epirubicin enhanced the formation of apoptotic blebs and chromatin fragmentation. When epirubicin was combined with tamoxifen, peculiar nuclear structures were formed. CONCLUSIONS: Hormonal agents may modulate anthracycline activity towards specific patterns in eliciting cell death, via autophagy and/or as yet unknown nucleolus-specific interactions. 相似文献
8.
Mehmet Celik Yusuf Yilmaz Muzaffer Kahyaoglu Ayhan Kup Yusuf Bilen Regaip Zehir 《Journal of cardiac surgery》2021,36(1):336-338
Right ventricular (RV) perforation is a rare but life‐threatening complication of pericardiocentesis and is usually treated surgically. We presented a case of RV free wall perforation, which occurred during pericardiocentesis and tried to be closed percutaneously with the Amplatzer vascular plug‐III (AVP‐III) device. The occluder device sealed the perforation, but it was in an insecure position; therefore, the patient underwent surgical repair. As an AVP‐III device, with a middle disk thicker than the RV myocardium, it may cause the RV myocardium to stretch outwards, so it should not be used for the treatment of RV perforation by the transcatheter way. 相似文献
9.
Ayhan Kuzu Îskender Alaçayir Cüneyt Köksoy Özlem Yazar Ercüment Kuterdem 《Transplant international》1995,8(3):226-228
The vasodilatation induced by acetylcholine (ACh) in a rabbit isolated perfused kidney was abolished when the tissue was exposed to cold ischemia for 72 h in Euro-Collins (EC) solution. This vasodilatation is due to the release of endothelium-derived relaxing factor (EDRF) from renal vasculature as evidenced by the attenuation following methylene blue pretreatment. When kidneys were preserved in EC solution containing UK 38 485, a thromboxane synthase inhibitor, or nicardipine, a calcium channel blocker, ACh-induced vasodilatation persisted after 72 h of cold ischemia. These results were taken as evidence of tissue protective activity of UK 38 485 and nicardipine and have promising implications for cadaveric kidney transplantation.This paper was presented at the 35th World Congress of the International Society of Surgery in Hong Kong in August 1993 相似文献
10.
E. S. Guvendag Guven S. Guven I. Esinler A. Ayhan T. Kucukali† & A. Usubutun† 《International journal of gynecological cancer》2004,14(3):558-563
Placental site trophoblastic tumor is a rare neoplasm that arises from intermediate trophoblasts and shows diversity of biological behaviors, resulting in the absence of consistency in treatment modalities. A case of placental site trophoblastic tumor that extended to the cervix, with primary manifestation of amenorrhea and yellow foul-smelling vaginal discharge, is presented. Total abdominal hysterectomy was performed initially, and serial measurements of human chorionic gonadotropin levels were obtained. She was admitted with metastases to brain and lung 1.5 years after surgery. Combination chemotherapy (etoposide-methotrexate-dactinomycin/cyclophosphamide-vincristine) and radiotherapy were administered. There was no significant response to chemoradiotherapy. Despite changing chemotherapy regimen, she is still alive with progressive disease. 相似文献