全文获取类型
收费全文 | 1834413篇 |
免费 | 129156篇 |
国内免费 | 3401篇 |
专业分类
耳鼻咽喉 | 26697篇 |
儿科学 | 52056篇 |
妇产科学 | 50058篇 |
基础医学 | 261015篇 |
口腔科学 | 55715篇 |
临床医学 | 158722篇 |
内科学 | 350461篇 |
皮肤病学 | 37928篇 |
神经病学 | 141309篇 |
特种医学 | 75459篇 |
外国民族医学 | 334篇 |
外科学 | 291903篇 |
综合类 | 40739篇 |
现状与发展 | 3篇 |
一般理论 | 476篇 |
预防医学 | 135361篇 |
眼科学 | 43001篇 |
药学 | 139230篇 |
5篇 | |
中国医学 | 3548篇 |
肿瘤学 | 102950篇 |
出版年
2018年 | 18368篇 |
2017年 | 15404篇 |
2016年 | 16093篇 |
2015年 | 19669篇 |
2014年 | 25252篇 |
2013年 | 35012篇 |
2012年 | 52198篇 |
2011年 | 49565篇 |
2010年 | 28765篇 |
2009年 | 28835篇 |
2008年 | 45654篇 |
2007年 | 49288篇 |
2006年 | 50130篇 |
2005年 | 56100篇 |
2004年 | 56399篇 |
2003年 | 50654篇 |
2002年 | 45087篇 |
2001年 | 85821篇 |
2000年 | 86541篇 |
1999年 | 75600篇 |
1998年 | 19088篇 |
1997年 | 16958篇 |
1996年 | 17023篇 |
1995年 | 16001篇 |
1994年 | 15034篇 |
1992年 | 62273篇 |
1991年 | 60627篇 |
1990年 | 59504篇 |
1989年 | 57835篇 |
1988年 | 53522篇 |
1987年 | 52235篇 |
1986年 | 49142篇 |
1985年 | 47118篇 |
1984年 | 34737篇 |
1983年 | 29470篇 |
1982年 | 16407篇 |
1981年 | 14640篇 |
1979年 | 33442篇 |
1978年 | 23134篇 |
1977年 | 19478篇 |
1976年 | 17427篇 |
1975年 | 19763篇 |
1974年 | 24382篇 |
1973年 | 23079篇 |
1972年 | 22008篇 |
1971年 | 20855篇 |
1970年 | 19847篇 |
1969年 | 19079篇 |
1968年 | 17241篇 |
1967年 | 15917篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
R Menapace W Binder C Skorpik H D Gnad 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》1989,198(3):129-134
Steady flattening of the tumor, increasing reflectivity and decreasing vascularity are echographic signs of successful irradiation treatment. The specific example of an irradiated choroidal melanoma shows that the absence of echographic changes by no means excludes tumor destruction. Because of a dense vitreous body hemorrhage, the melanoma could only be evaluated echographically. Since the echogram lacked evidence of regression, the tumor was locally resected 5 months later. Histology, however, revealed an amorphous mass of dead tissue pervaded by intact vessels. Apparently a successfully irradiated melanoma may generate an echo typical of vital melanoma tissue. The authors therefore draw the conclusion that only a steady tumor growth, as substantiated by an echogram, may be considered an unambiguous sign of tumor vitality. 相似文献
993.
D H Char J R Castro J M Quivey T L Phillips A R Irvine R D Stone S Kroll 《Ophthalmology》1989,96(12):1708-1715
The optimum radiation therapy for uveal melanoma is uncertain. Both helium ion irradiation and 125I brachytherapy have been used to treat this neoplasm. This investigation analyzed the control and complication rates of uveal melanomas treated with helium ions of 125I plaques. In both a retrospective and a prospective dynamically balanced study, the control rates appeared to be similar. There were more posterior segment complications after 125I plaques and more anterior segment complications, including neovascular glaucoma, after helium ion irradiation. The follow-up period is too short to draw definitive conclusions on the radiation complications. Overall, approximately 89% of eyes were retained and less than 4% of treated eyes were removed because of failure to control the tumor. 相似文献
994.
The term perfusion has varied connotations in different situations. The word perfusion comes from the Latin to pour or diffuse through or over. Myocardial perfusion depends on (a) coronary artery or vessel flow, and (b) myocardial or muscle flow. The factors which determine perfusion at rest and during stress in coronary vessels and within the myocardium are clearly related but not with a predictable linear relationship. In animals there is extensive literature concerning the regulation of coronary flow and perfusion obtained by many sophisticated methods. In contrast, the techniques that are applicable to humans are relatively crude. To date, the clinical data available suggests that the normal control of coronary flow in man and in dogs is fairly similar but that models of pathology in animals bear little relation to the compensatory changes found in the coronary circulation in man. Although the data available is limited and subject to many technical inaccuracies, this article is confined to the assessment of myocardial perfusion in clinical practice. 相似文献
995.
H Ikenaga T Ogihara S Iyori S Kou H Yoshikawa M M Okura 《Postgraduate medical journal》1989,65(768):761-764
A case of a young Japanese woman with long-standing ulcerative colitis complicated by preinfarction angina due to Takayasu's aortitis is presented. Successful emergency aorto-coronary bypass operation was performed. Whether the association of these two diseases can be explained by a common mechanism is discussed. 相似文献
996.
Iu A Kuchak N V Sokolovski? T F Kharchenko V Iu Romanovski? 《Gigiena truda i professional'nye zabolevaniia》1989,(9):12-14
The first phase of data bank of hazard (DBH) of polymers has been developed and put into operation on the basis of CM-computers. DBH is a factographical computer-based system of data collection, storage and processing aimed at complex assessment of material and substance hazard. Systems approach to the analysis of material's characteristics serves as a methodological basis. DBH data base includes a set of input and output documents according to 5 types of biological hazards involving sanitary and chemical surveillance, fire hazard and thermodestruction, the data on material's microbiologic resistance, their electrifying and toxicohygienic characteristics. DUAMC-3 operational system, DUAMC. DBH software are included into the system of data banks of materials' technological properties. 相似文献
997.
998.
Biologic distribution data in the rat were obtained for the alpha-1 adrenoceptor imaging agent (+/-) 2-[beta-(iodo-4-hydroxyphenyl)ethylaminomethyl]tetralone (HEAT) labeled with [125I]. The major excretory routes were through the liver (67%) and the kidney (33%). Internal radiation absorbed dose estimates to nine source organs, total body, the GI tract, gonads, and red bone marrow were calculated for the human using the physical decay data for [123I]. The critical organ was found to be the lower large intestine, receiving 1.1 rad per mCi of [123I]HEAT administered. The total-body dose was found to be 58 mrad per mCi. 相似文献
999.
1000.
K Nieber P Henklein T Ott P Oehme 《Zeitschrift für die gesamte innere Medizin und ihre Grenzgebiete》1987,42(18):501-506
This issue comprises selected topics of CCK peptides. CCK peptides are linear peptides and were found within and outside the CNS. There is growing evidence that CCK peptides play a physiological role in food intake, contraction of gallbladder and regulation of motility of the gastrointestinal system. New aspects of the CCK research are concentrated on interaction with other transmitter systems especially with the dopamine and opioid system. The therapeutic action to improve clinical symptoms in human is unclear up to new. World-wide, the interest is focused to determine the potential of CCK peptides as an antipsychotic agent by controlled clinical studies. 相似文献