全文获取类型
收费全文 | 1695400篇 |
免费 | 123708篇 |
国内免费 | 3785篇 |
专业分类
耳鼻咽喉 | 21751篇 |
儿科学 | 55635篇 |
妇产科学 | 46151篇 |
基础医学 | 241230篇 |
口腔科学 | 48743篇 |
临床医学 | 151316篇 |
内科学 | 333530篇 |
皮肤病学 | 38659篇 |
神经病学 | 131151篇 |
特种医学 | 63872篇 |
外国民族医学 | 242篇 |
外科学 | 257272篇 |
综合类 | 38948篇 |
现状与发展 | 4篇 |
一般理论 | 531篇 |
预防医学 | 124225篇 |
眼科学 | 40221篇 |
药学 | 123612篇 |
7篇 | |
中国医学 | 4478篇 |
肿瘤学 | 101315篇 |
出版年
2021年 | 12791篇 |
2019年 | 13528篇 |
2018年 | 19954篇 |
2017年 | 15214篇 |
2016年 | 16615篇 |
2015年 | 18962篇 |
2014年 | 26217篇 |
2013年 | 37946篇 |
2012年 | 52734篇 |
2011年 | 55430篇 |
2010年 | 32780篇 |
2009年 | 30696篇 |
2008年 | 51532篇 |
2007年 | 54804篇 |
2006年 | 55260篇 |
2005年 | 52541篇 |
2004年 | 50751篇 |
2003年 | 48158篇 |
2002年 | 46373篇 |
2001年 | 91784篇 |
2000年 | 93607篇 |
1999年 | 76959篇 |
1998年 | 19719篇 |
1997年 | 17268篇 |
1996年 | 17392篇 |
1995年 | 16745篇 |
1994年 | 15291篇 |
1993年 | 14074篇 |
1992年 | 57385篇 |
1991年 | 55273篇 |
1990年 | 52974篇 |
1989年 | 50749篇 |
1988年 | 46132篇 |
1987年 | 44940篇 |
1986年 | 42229篇 |
1985年 | 39991篇 |
1984年 | 29351篇 |
1983年 | 24910篇 |
1982年 | 13898篇 |
1979年 | 25530篇 |
1978年 | 17574篇 |
1977年 | 14907篇 |
1976年 | 13877篇 |
1975年 | 14565篇 |
1974年 | 17633篇 |
1973年 | 16948篇 |
1972年 | 15674篇 |
1971年 | 14453篇 |
1970年 | 13431篇 |
1969年 | 12519篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
S Kyle R S Stubbs R J Stewart 《The Australian and New Zealand journal of surgery》1988,58(11):895-898
Choledochal cyst is an unusual but serious condition which most commonly affects Oriental people. Recent experience of three patients with this condition in whom diagnosis was made by ultrasound examination is reported. Cholangiography (ERCP or PTC) was performed in two of the cases to define the anatomy. All three cases were successfully managed by cyst excision and biliary reconstruction by Roux-en-Y hepaticojejunostomy. The rationale for and importance of cyst excision are discussed. 相似文献
102.
Clinical versus ultrasonographic evaluation of scrotal disorders 总被引:1,自引:0,他引:1
B Kromann-Andersen L B Hansen P N Larsen K Lawetz P Lynge D Lysen S P Nielsen K H Stockholm P Foged 《British journal of urology》1988,61(4):350-353
Clinical and ultrasonographic examinations of scrotal disorders were compared in 166 patients in order to determine their ability to distinguish between those diseases requiring surgery and those requiring clinical follow-up only. Ultrasound examinations were efficient in discriminating between normal and pathological findings. Extra-testicular lesions were readily differentiated from testicular ones. Although both clinical and ultrasonographic examinations had high sensitivity (90%) in detecting testicular cancer, the number of false positive findings was smaller after ultrasound examination. This gave a predictive value of a positive test of 53% after ultrasound examination but only 33% after clinical examination. Ultrasound examination may, therefore, reduce the number of surgical explorations in the scrotum and should be performed in patients with suspected testicular pathology based on history and palpatory findings. 相似文献
103.
104.
Twenty-one mature New Zealand white female rabbits were allocated into three groups of seven rabbits. Group I received a bolus of doughy Simplex polymethylmethacrylate (PMMA) cement injected into the proximal tibia through a drill hole. Group II received a preformed, cooled, bulk PMMA pellet. Group III had particulate PMMA powder implanted. The operated, but nonimplanted, left tibiae served as controls. Animals were killed after four months. Histologically, both Group I and Group II demonstrated a thin, fibrous tissue membrane at the implant interface. Particulate PMMA (Group III) stimulated a much thicker, florid, foreign body reaction composed of histiocytes and giant cells. The foreign body response to particulate acrylic cement was similar to that seen in failed cemented joint replacement arthroplasty in humans. 相似文献
105.
Summary. In this study, we have examined our records for the isolation of Candida tropicalis from clinical specimens of patients with heterogeneous clinical presentations during the past 5 years. We have found that this species ranks third among all yeasts in frequency of isolation from clinical specimens and that the trend of recovery from the specimens is rising over the years. The isolation rate of C. tropicalis was highest from urine specimens (36%) followed by respiratory specimens (22%). The frequency of isolation of C. tropicalis from vaginal specimens was relatively high (14%), however the trend was declining over the years. In general, the high recovery of Candida tropicalis from clinical specimens of patients with variable disease supports the views of this organism being a major pathogen.
Zusammenfassung. Die Studie basiert auf einer Durchsicht der Patientenarchive der letzten fünf Jahre auf die Isolationshäufigkeit von Candida tropicalis aus klinischen Untersuchungsmaterialien von Patienten mit unterschiedlichen klinischen Krankheitsbildern. Diese Hefeart war die dritthäufigste mit steigender Tendenz über die Jahre. Die Isolierungsrate von C. tropicalis war am höchsten aus Urin (36%), gefolgt von Respirationstrakt-Materialien (22%). Die Isolationshäufigkeit aus dem hinteren Scheidengewölbe war relativ hoch (14%), nahm jedoch mit den jahren ab. Allgemein unterstreicht die hohe Isolationsrate von C. tropicalis aus klinischen Untersuchungsmaterialien die ätiologische Bedeutung dieses Erregers. 相似文献
Zusammenfassung. Die Studie basiert auf einer Durchsicht der Patientenarchive der letzten fünf Jahre auf die Isolationshäufigkeit von Candida tropicalis aus klinischen Untersuchungsmaterialien von Patienten mit unterschiedlichen klinischen Krankheitsbildern. Diese Hefeart war die dritthäufigste mit steigender Tendenz über die Jahre. Die Isolierungsrate von C. tropicalis war am höchsten aus Urin (36%), gefolgt von Respirationstrakt-Materialien (22%). Die Isolationshäufigkeit aus dem hinteren Scheidengewölbe war relativ hoch (14%), nahm jedoch mit den jahren ab. Allgemein unterstreicht die hohe Isolationsrate von C. tropicalis aus klinischen Untersuchungsmaterialien die ätiologische Bedeutung dieses Erregers. 相似文献
106.
107.
C. R. Irwin T. Myrillas M. Smyth J. Doogan C. Rice S. L. Schor 《Journal of oral pathology & medicine》1998,27(6):255-259
Fibroblasts incorporated within collagen gels induce a cell-mediated contraction of the gel to form a three-dimensional, tissue-like structure by a mechanism thought to mimic wound contraction in vivo . In this study a gel contraction model was used to investigate the ability of fibroblasts derived from adult gingiva, adult skin and fetal skin to organise a collagen matrix. In addition the effects of interleukin-1β (IL-1β) on the contraction process was also investigated. Over the concentration range 5-50 U/ml, IL-1β induced a statistically significant inhibition of gel contraction in all fibroblast cell types ( P <0.05), although fetal fibroblasts appeared least responsive and gingival fibroblasts most responsive to the inhibitory effects of this cytokine. Comparison of gel contraction by the different fibroblast strains indicated that fetal and gingival fibroblasts shared similar contraction kinetics. For the adult skin fibroblasts, three of five strains studied showed significantly diminished levels of gel contraction compared to fetal and gingival cells. This apparent difference in fibroblast phenotype may, at least in part, explain the fetal-like wound healing pattern seen in the oral mucosa. 相似文献
108.
A. HAZIOT I. KATZ G. W. RONG X. Y. LIN J. SILVER & S. M. GOYERT 《Scandinavian journal of immunology》1997,46(3):242-245
Membrane-bound CD14 acts as a receptor for lipopolysaccharide (LPS) on monocytes/macrophages and neutrophils. Studies have suggested that the activation of monocytes/macrophages by the binding of LPS to membrane-bound CD14 may require the association of a signal-transducing molecule with membrane-bound CD14. The observation that non-CD14 expressing cells, such as endothelial cells, can nevertheless be activated by a complex of LPS and a soluble form of CD14 (sCD14) suggests that the receptor for this complex may be identical to the signal transducing molecule associated with membrane-bound CD14. The studies described show that two CD14-specific MoAb are able to block the LPS-induced activation of endothelial cells but do not affect the response of monocytes to LPS. This suggests that the interaction of the sCD14:LPS complex with endothelial cells is distinct from the interaction of membrane-bound CD14 with its putative signal-transducing molecule. 相似文献
109.
M M Smith J E Thompson D Thomas M Castillo D Carrier S K Mukherji D Gilliam 《AJNR. American journal of neuroradiology》1997,18(2):327
Choristomas, masses of normal tissues in aberrant locations, contain smooth muscle fibers and fibrous tissues. We describe the MR imaging features of two choristomas located in the internal auditory canals and arising from the facial and vestibulocochlear nerves. Both lesions enhanced with contrast material. In one case, enhancement was seen in the geniculate ganglion and greater superficial petrosal nerve. In the other, a medial component enhanced less than the lateral component did. 相似文献
110.
A. Al Tahan S. Arora A. Alzeer F. Al Tahan T. Malabarey A. Daif 《European journal of neurology》1997,4(1):52-58
The diagnosis of acute disseminated encephalomyelitis (ADEM) is frequently missed or delayed with consequent delay in instituting therapy in the crucial phase of the illness. The role of MRI in the diagnosis of ADEM is well established, however, the value of its early utilization of treatment on the outcome of patients has not been adequately stressed. Three patients with ADEM are described. Delay in the diagnosis of the first was associated with severe sequelae, while in the other two early diagnosis and institution of corticosteroid therapy which was facilitated by MRI, was associated with a better outcome. MRI should be carried out early once the diagosis of ADEM is entertained. 相似文献