全文获取类型
收费全文 | 700篇 |
免费 | 27篇 |
国内免费 | 4篇 |
专业分类
731篇 |
出版年
2022年 | 3篇 |
2021年 | 14篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 17篇 |
2017年 | 22篇 |
2016年 | 26篇 |
2015年 | 15篇 |
2014年 | 25篇 |
2013年 | 18篇 |
2012年 | 24篇 |
2011年 | 33篇 |
2010年 | 24篇 |
2009年 | 31篇 |
2008年 | 33篇 |
2007年 | 33篇 |
2006年 | 24篇 |
2005年 | 21篇 |
2004年 | 26篇 |
2003年 | 30篇 |
2002年 | 20篇 |
2001年 | 22篇 |
2000年 | 18篇 |
1999年 | 17篇 |
1998年 | 8篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 7篇 |
1991年 | 10篇 |
1990年 | 12篇 |
1989年 | 18篇 |
1988年 | 13篇 |
1987年 | 16篇 |
1986年 | 13篇 |
1985年 | 10篇 |
1984年 | 7篇 |
1983年 | 8篇 |
1980年 | 3篇 |
1979年 | 7篇 |
1978年 | 5篇 |
1975年 | 4篇 |
1974年 | 6篇 |
1973年 | 5篇 |
1972年 | 11篇 |
1971年 | 9篇 |
1970年 | 9篇 |
1969年 | 8篇 |
1967年 | 3篇 |
1966年 | 4篇 |
1965年 | 3篇 |
排序方式: 共有731条查询结果,搜索用时 9 毫秒
51.
52.
Agafonova OV Borovskiĭ IV Demchenko VV Pavlova AM Filatova IM 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1999,(1):119-120
During the recent 10 years, 1987-1997, syphilis morbidity was found to increase 60-fold in Omsk Province. In 1997 adolescents constituted 6.0% in the structure of persons who contacted the disease. In this year more than 500 adolescent using drugs were registered in the region. The introduction of drugs by injection was practiced by 9.6% of the adolescents. The program aimed mainly at changing the behavior of young people with orientation on the choice of a healthy mode of life and theirs information about risk factors associated with sex transmitted diseases particularly HIV infection is discussed. 相似文献
53.
Pavlova LI Gorbunov MA Vorob'eva MS Karavanov AS Grachev VP Ladyshenskaia IP Rasshchepkina MN Mel'nikova LN Lebedeva TM Mel'nikov NA Gusmanova AG Deviatkov MIu Rozanova EV Mukachev MA 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1999,(6):50-53
The word deals with the results obtained in the study of the reactogenicity and immunological activity of concentrated and inactivated tissue-culture tick-borne encephalitis vaccine, manufactured by the Chumakov Institute of Poliomyelitis and Viral Encephalitides, in the immunization of children and adolescents. The vaccine proved to be moderately reactogenic and exhibited pronounced immunological activity. In 91.5% of the immunized children the fourfold increase of the antibody level was observed. On the basis of the data obtained in this study the tick-borne encephalitis vaccine was recommended for use in medical practice for the prophylaxis of tick-borne encephalitis among children and adolescents. 相似文献
54.
55.
Salmonella typhimurium population in water environment under the influence of temperature 总被引:1,自引:0,他引:1
The strategy of the adaptation of S. typhimurium population to water environment under the influence of temperature factor was studied by scanning electron microscopy. Salmonellae were found to adhere to the surface of the Daphnia chitin covering. The study revealed that S. typhimurium population existed in water in the form of covered microcolonies as well as in the form of spheroplast-type cells and small cells in the L-form, joined with bands. The viability of salmonellae in water environment was studied without interaction and following interaction with Daphnia. 相似文献
56.
57.
Pavlova OG Frolov AG Aleksandrov AV 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2001,51(1):40-51
Kinematic analysis of the head and the forelimb movements in dogs has been done during elaboration the instrumental tonic forelimb flexion when the head was bent down to foodwell. It was found, that in naive dogs the forelimb flexion was accompanied by anticipatory lifting of the head, the head lowering evoked extension of the flexed forelimb. Therefore simultaneous holding of the lifted limb and the lowered head was impossible and could be achieved only by learning. Studying of the dynamics of transformation of the innate (natural) head-forelimb coordination during learning has shown that innate relationship between phasic head-forelimb movements, which was lost at the early stage could spontaneously restore for a short time in trained dogs. It was found between low-amplitude head-forelimb oscillations which did not disturb the learnt tonic forelimb flexion, when the head was bent down. The innate coordination is supposed to be an inborn and in the given conditions the only possible way of the forelimb lifting, in which the anticipatory lifting of the head might facilitate the limb flexion. That's why lowering of the head provoked extension of the flexed limb. Contrary to the known hypothesis [4] that the mechanism of elaboration of the novel coordination is connected with suppression of the interfering innate coordination, it is proposed to consider the elaborated coordination as the novel way of the forelimb lifting in the forced posture of the lowered head. The novel flexion of the forelimb, as supposed, became possible by changing its innate organization (muscular pattern). 相似文献
58.
Flekhter O. B. Boreko E. I. Nigmatullina L. R. Pavlova N. I. Nikolaeva S. N. Savinova O. V. Eremin V. F. Baltina L. A. Galin F. Z. Tolstikov G. A. 《Russian Journal of Bioorganic Chemistry》2003,29(3):296-302
New nitrogen-containing derivatives of betulinic and betulonic acids, hydrazides and N"-benzalhydrazides, were synthesized. Their antiviral activities toward viruses of influenza A virus, herpes simplex type I virus, enterovirus ECHO6, and HIV-1 were studied in vitro. Betulinic acid 3-oxime was found to have the highest activity against the influenza virus. Betulonic acid, betulinic acid 4-chlorobenzalhydrazide, betulonic acid 3-oxime benzalhydrazide, and betulinic acid hydrazide inhibited the replication of herpes simplex type I virus. Betulinic acid hydrazide also showed antiviral activity toward HIV-1. All the derivatives of betulinic acid under study displayed a low antiviral activity toward enterovirus ECHO6. 相似文献
59.
Five stable hybridoma lines producing monoclonal antibodies to Corynebacterium sepedonicum were obtained. The specificity of monoclonal antibodies obtained was characterized. Interactions of the antibodies with native cells and antigenic preparations from bacterial cell extracts were studied. The epitope specificity of these antibodies to their recognized antigens and the use of the antibodies in advanced immunodiagnostic assays are discussed. 相似文献
60.