全文获取类型
收费全文 | 147篇 |
免费 | 20篇 |
出版年
2021年 | 3篇 |
2019年 | 1篇 |
2016年 | 2篇 |
2015年 | 5篇 |
2014年 | 5篇 |
2013年 | 5篇 |
2012年 | 4篇 |
2011年 | 5篇 |
2010年 | 10篇 |
2009年 | 2篇 |
2008年 | 6篇 |
2007年 | 6篇 |
2006年 | 12篇 |
2005年 | 13篇 |
2004年 | 5篇 |
2003年 | 3篇 |
2002年 | 5篇 |
2001年 | 11篇 |
2000年 | 2篇 |
1999年 | 7篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 5篇 |
1982年 | 7篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1965年 | 3篇 |
1950年 | 1篇 |
1948年 | 1篇 |
1945年 | 2篇 |
1941年 | 1篇 |
排序方式: 共有167条查询结果,搜索用时 140 毫秒
161.
Antibodies directed to modified nucleosides recognize the nucleoside (antigen) when it is present in an intact tRNA molecule. The general application of anti-nucleoside immunoadsorbent chromatography, however, has been greatly impeded by the apparent inefficiency and low capacity of conventional immunoadsorbents for transfer RNA. Antibodies specific for isopentenyladenosine (i6A) were employed to investigate the efficacy of various immunoadsorbents with respect to immobilization of antibody protein and with respect to their ability to bind i6A-containing tRNAs. Biologically active anti-i6A was recovered in high yield (80-88%) by affinity chromatography on i6A-adipate-Sepharose 4B or i6A-butane diglycidyl ether-Sepharose 4B using either 15% pyridine in phosphate-buffered saline or 0.2 M acetic acid as eluents. The binding capacity of various anti-i6A antibody immunoadsorbents was evaluated. While both anti-i6A antibody-protein A-agarose-iminothiolane (ITL) and anti-i6A antibody-protein A-agarose-dimethyl suberimidate showed a high capacity for i6A-tRNA, the latter column is much less efficient with respect to antibody immobilization. Under optimal conditions, the ITL immunoadsorbent binds 5-6 nmol of i6A/mg of antibody protein. With respect to bulk tRNA, 1 mg of antibody protein (ITL immunoadsorbent) binds all of the i6A-tRNA in a 1-mg sample. 相似文献
162.
David F. Raney Virginia Abernethy Peter S. Rodman 《Primates; journal of primatology》1981,22(3):368-378
Female bonnet macaques are ranked according to naturally occurring dyadic aggressive interactions. Several possible correlates
of these ranks are examined. Maternal rank and early life history are found to be highly correlated with rank. In addition,
a number of social relationships (female/female presentations, female/female mounts, contact among females and aggression)
are found to be related to rank. The meaning of rank outside of head to head encounters is discussed.
This research was supported in part by the California Primate Research Center, University of California, Davis, Davis, California
95616. 相似文献
163.
164.
165.
Polyethylene bulbs derived from sterile transfer pipets were evaluated as leak-proof vials for cryopreservation of parasitic protozoa. The bulbs were easily frozen and stored in conventional liquid nitrogen refrigeration equipment and were less expensive and safer to handle than plastic screw-capped cryovials. The easily testable heat seal of the polyethylene bulb never failed during longterm immersion in liquid nitrogen, and dispensing of thawed material was simple and safe. Good survival of L. donovani (80%), T. rhodesiense (95%), and C. fasciculata (95%) was obtained after cryopreservation in polyethylene bulbs or plastic screw-capped vials. The polyethylene bulb was considered an excellent container for the safe cryopreservation of pathogens and other biological material. 相似文献
166.
SYNOPSIS. Ochromonas danica in a complex natural growth medium dies at 6–10 C in 4 days; O. malhamensis in ∼2 days. O. danica grown in the medium supplemented with 4.0% glycerol survived at −10±2 C for 35 days, and with 8% glycerol 29 days. O. malhamensis lasted only to 5 days in these media supplemented with 4% glycerol. Ethylene glycol and dimethylsulfoxide were too toxic to be effective. Difficulties in freeze-preservation of certain other phagocytic cells, notably blood granulocytes having comparatively simple flexuous outer membranes, add interest to use of O. danica and O. malhamensis as test organisms for preservation methods, especially in the convenient, inexpensive -10 to -20 C range. Biphasic media with an overlay of distilled water serve for conservation at room temperature. Problems of mutational erosion of these photosynthetic phagotrophs are discussed. 相似文献
167.