全文获取类型
收费全文 | 527篇 |
免费 | 22篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 13篇 |
妇产科学 | 1篇 |
基础医学 | 42篇 |
口腔科学 | 19篇 |
临床医学 | 44篇 |
内科学 | 167篇 |
皮肤病学 | 8篇 |
神经病学 | 66篇 |
特种医学 | 48篇 |
外国民族医学 | 1篇 |
外科学 | 46篇 |
综合类 | 4篇 |
预防医学 | 48篇 |
药学 | 24篇 |
中国医学 | 1篇 |
肿瘤学 | 26篇 |
出版年
2022年 | 4篇 |
2021年 | 7篇 |
2019年 | 6篇 |
2018年 | 6篇 |
2016年 | 10篇 |
2015年 | 12篇 |
2014年 | 12篇 |
2013年 | 26篇 |
2012年 | 18篇 |
2011年 | 24篇 |
2010年 | 15篇 |
2009年 | 16篇 |
2008年 | 14篇 |
2007年 | 35篇 |
2006年 | 13篇 |
2005年 | 17篇 |
2004年 | 6篇 |
2003年 | 4篇 |
2002年 | 16篇 |
2001年 | 9篇 |
2000年 | 14篇 |
1999年 | 7篇 |
1998年 | 14篇 |
1997年 | 13篇 |
1996年 | 6篇 |
1995年 | 9篇 |
1994年 | 4篇 |
1993年 | 8篇 |
1992年 | 8篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 10篇 |
1988年 | 17篇 |
1987年 | 13篇 |
1986年 | 9篇 |
1985年 | 4篇 |
1984年 | 12篇 |
1983年 | 10篇 |
1982年 | 11篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1979年 | 10篇 |
1978年 | 15篇 |
1977年 | 9篇 |
1976年 | 16篇 |
1975年 | 21篇 |
1974年 | 13篇 |
1973年 | 5篇 |
1972年 | 3篇 |
1968年 | 2篇 |
排序方式: 共有562条查询结果,搜索用时 15 毫秒
1.
2.
1-乙基-6-氟-1,4-二氢-4-氧代-7-(4-芳酰硫代氨甲酰基-1-哌嗪基)-3-喹啉羧酸的合成及抗菌作用 总被引:4,自引:1,他引:3
Thirteen new 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-aroyl-thiocarbamoyl- 1 piperazinyl)-3-quinoline carboxylic acids were prepared, Their structures were characterized by elemental analysis, IR, HNMR and MS spectra.Preliminary pharmacological tests indicated that some of compounds Ia~m possess strong inhibiting activity against Escherichia coli, Bacillus subtilis and Proteus at concentration of 100 μg/ml. 相似文献
3.
4.
Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
5.
The automatic implantable cardioverter-defibrillator. Clinical experience, complications, and follow-up in 25 patients 总被引:1,自引:0,他引:1
J Borbola P Denes M D Ezri R G Hauser C Serry M D Goldin 《Archives of internal medicine》1988,148(1):70-76
Twenty-five patients with recurrent ventricular tachyarrhythmias underwent implantation of an automatic implantable cardioverter-defibrillator. The mean length of follow-up was 11.9 +/- 10.8 months. Before the implantation, the patients had survived one or more cardiac arrests (mean, 1.7; range, 1 to 4) and episodes of syncope (mean, 2.2; range, 2 to 3) and had received 6.0 +/- 1.0 antiarrhythmic drug trials. The in-hospital complications included death (two patients), reoperation (one patient), intraoperative myocardial infarction (one patient), sensing-failure (one patient), infection (five patients), and pocket seroma (two patients). The posthospital complications included device failure (four patients), device deactivation (one patient), and inappropriate discharge (two patients). The device discharged appropriately in seven patients due to sustained ventricular tachycardia. During electrophysiologic measurements, the energy requirement for successful cardioversion-defibrillation was related to the type of ventricular arrhythmia induced (monomorphic or pleomorphic ventricular tachycardia or fibrillation). Ventricular tachycardia acceleration occurred in ten patients (40%). No significant changes were found in the size of the electrograms or in the cardioversion threshold during early and late follow-up measurements. Life table analysis showed a 12-month survival rate of 86% and an arrhythmic death survival rate of 100%. We confirm the improved rate of survival in this high-risk group of patients, despite significant complications. 相似文献
6.
Desmond FS Cormack RMN RGN MPhil DipEd PhD DipN Honorary Reader in Health Nursing William Reynolds RMN RNT RGN MPhil Senior Tutor 《Journal of advanced nursing》1992,17(12):1472-1478
Arguably, nursing, like all health care disciplines, is an applied science. Essentially, this refers to the application of theory in order to understand and respond to the health problems of clients. These theories may be drawn (borrowed) from any applied science, or generated inductively from clinical nursing practice. Alternatively, nurses may attempt to apply deductive theory (global theoretical frameworks) known as nursing models. In this paper, all theoretical approaches, irrespective of origin, are referred to as models used by nurses. Thirteen criteria by which clinicians, and others, can evaluate the clinical and practical utility of models used by nurses which are expressed in the form of questions are identified and discussed. The criteria are an extension, both in detail and in number, of those developed by Reynolds and Cormack and subsequently applied by those writers to the Johnson Behavioural System Model of Nursing. The value, or otherwise, of individual models, or of models in general, will not be discussed in this paper. However, the authors propose that if the evaluation criteria described here are applied to existing models, serious deficits will be identified in relation to their clinical and practical utility. 相似文献
7.
CD59 blocks not only the insertion of C9 into MAC but inhibits ion channel formation by homologous C5b-8 as well as C5b-9 总被引:4,自引:0,他引:4
Imre Farkas‡ Lajos Baranyi† Yasushige Ishikawa† Noriko Okada Csaba Bohata‡ Denes Budai§ Atsuo Fukuda¶ Masaki Imai Hidechika Okada 《The Journal of physiology》2002,539(2):537-545
Activation of the complement system on the cell surface results in the insertion of pore forming membrane attack complexes (MAC, C5b-9). In order to protect themselves from the complement attack, the cells express several regulatory molecules, including the terminal complex regulator CD59 that inhibits assembly of the large MACs by inhibiting the insertion of additional C9 molecules into the C5b-9 complex. Using the whole cell patch clamp method, we were able to measure accumulation of homologous MACs in the membrane of CD59− human B-cells, which formed non-selective ion channels with a total conductance of 360 ± 24 pS as measured at the beginning of the steady-state phase of the inward currents. C5b-8 and small-size MAC (MAC containing only a single C9) can also form ion channels. Nevertheless, in CD59+ human B-cells in spite of small-size MAC formation, an ion current could not be detected. In addition, restoring CD59 to the membrane of the CD59− cells inhibited the serum-evoked inward current. The ion channels formed by the small-size MAC were therefore sealed, indicating that CD59 directly interfered with the pore formation of C5b-8 as well as that of small-size C5b-9. These results offer an explanation as to why CD59-expressing cells are not leaky in spite of a buildup of homologous C5b-8 and small-size MAC. Our experiments also confirmed that ion channel inhibition by CD59 is subject to homologous restriction and that CD59 cannot block the conductivity of MAC when generated by xenogenic (rabbit) serum. 相似文献
8.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
9.
Contribution to the problem of giant cell astrocytomas 总被引:1,自引:0,他引:1
Wilhelm Müller Felicitas Slowik Raimund Firsching Denes Afra Paul Sanker 《Neurosurgical review》1987,10(3):213-219
Histological, immunocytochemical, and biological features of 38 giant cell gliomas were investigated. The invasion of these tumors and its giant cells by histiocytes, lymphocytes, plasma cells, and especially by eosinophilic granulocytes is viewed as an immune response, which may explain a favorable clinical course. Fifty-three percent of the patients were younger than 45 years at the time of surgery. The average postoperative survival of 27.4 months was clearly longer than in glioblastoma. These biological features suggest a differentiation from glioblastoma multiforme. The classification of this entity as "monstrocellular astrocytoma" is proposed. 相似文献
10.