首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   123篇
  免费   9篇
  2020年   3篇
  2019年   1篇
  2018年   1篇
  2016年   1篇
  2014年   2篇
  2013年   7篇
  2012年   5篇
  2011年   13篇
  2010年   11篇
  2009年   2篇
  2008年   6篇
  2007年   6篇
  2006年   3篇
  2005年   9篇
  2004年   2篇
  2003年   8篇
  2002年   6篇
  2001年   5篇
  2000年   2篇
  1999年   11篇
  1998年   1篇
  1997年   1篇
  1996年   1篇
  1991年   1篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1984年   1篇
  1983年   3篇
  1982年   4篇
  1981年   1篇
  1979年   1篇
  1978年   1篇
  1975年   1篇
  1970年   1篇
  1962年   1篇
  1958年   1篇
  1907年   1篇
  1887年   3篇
排序方式: 共有132条查询结果,搜索用时 15 毫秒
91.
BioJava: an open-source framework for bioinformatics   总被引:1,自引:0,他引:1  
SUMMARY: BioJava is a mature open-source project that provides a framework for processing of biological data. BioJava contains powerful analysis and statistical routines, tools for parsing common file formats and packages for manipulating sequences and 3D structures. It enables rapid bioinformatics application development in the Java programming language. AVAILABILITY: BioJava is an open-source project distributed under the Lesser GPL (LGPL). BioJava can be downloaded from the BioJava website (http://www.biojava.org). BioJava requires Java 1.5 or higher. All queries should be directed to the BioJava mailing lists. Details are available at http://biojava.org/wiki/BioJava:MailingLists.  相似文献   
92.
Aphid parasitoids are important biological control agents. The possibility arises that whilst foraging on insect-resistant transgenic plants, they are themselves at risk from direct and indirect effects of the expression of a transgene used to control the pest species. A liquid artificial diet was successfully used to deliver the snowdrop lectin (Galanthus nivalis agglutinin; GNA) to the peach-potato aphid, Myzus persicae. Bioassays utilising artificial diet incorporating GNA, and excised leaves of the GNA-expressing transgenic potato line, GNA2#28, were performed to assess the potential effects of GNA on the development of the aphid parasitoid Aphidius ervi. The results indicate that GNA delivered via artificial diet to the aphids can be transferred through the trophic levels and has a dose-dependent effect on parasitoid development. Parasitoid larvae excreted most of the ingested GNA in the meconium but some of it was detected in the pupae. Although A. ervi development was not affected when developing within hosts feeding on transgenic potato leaves, this probably reflected sub-optimal expression of the toxin in the transgenic potato line used  相似文献   
93.
94.
The intact variant surface glycoprotein (VSG) ILTat 1.24 from Trypanosoma brucei has been crystallized. An amino-terminal domain of the protein comprising two thirds of the sequence had been crystallized previously after proteolytic digestion. Now intact VSG crystals have been grown from 50 mM-Mes (pH 6.5) containing 62% (w/v) saturated ammonium sulfate. The crystals are demonstrated to contain the intact VSG by h.p.l.c. gel filtration and reaction with an antibody to the inositol phosphate oligosaccharide on the VSG carboxy terminus. The space group of the crystals is P6(2)22 (or P6(4)22) with unit cell dimensions a = b = 184 A and c = 214 A. Preparative isoelectric focusing may have facilitated crystallization.  相似文献   
95.
R Cushman  J Down  N MacMillan  H Waclawik 《CMAJ》1990,143(2):108-112
The number of bicycle-related injuries has risen significantly with the increased popularity of bicycle riding in Canada. The risk of injury is highest among children. To assess the magnitude of the problem and to identify the contributing factors we used a questionnaire, injury reports and patient charts to survey bicycle-related injuries among children brought to the emergency department of the Children''s Hospital of Eastern Ontario, Ottawa, between May 1 and Sept. 30, 1988. The questionnaire was completed for 517 (91%) of the 568 children; 70% were boys, and the mean age was 9.4 years. Only 2% of the patients had been wearing a helmet at the time of injury, although 13% claimed to own one for cycling. Over 60% of the accidents were attributable to carelessness or poor bicycle control; mechanical failure and environmental hazards were minor factors. Over 80% of the injuries occurred within a kilometre of the child''s home. Of the 97 children admitted to hospital 49% had head and skull injuries and 40% had limb fractures. Bicycle-related injuries represented 14.8% of all nonwinter (Apr. 1 to Oct. 31) trauma admissions among children 5 years or older. Our results further document bicycle-related injuries as an important childhood problem and underscore the need for improved safety measures.  相似文献   
96.
97.
Tonoplast intrinsic protein isoforms as markers for vacuolar functions   总被引:21,自引:0,他引:21       下载免费PDF全文
GY Jauh  TE Phillips    JC Rogers 《The Plant cell》1999,11(10):1867-1882
Plant cell vacuoles may have storage or lytic functions, but biochemical markers specific for the tonoplasts of functionally distinct vacuoles are poorly defined. Here, we use antipeptide antibodies specific for the tonoplast intrinsic proteins alpha-TIP, gamma-TIP, and delta-TIP in confocal immunofluorescence experiments to test the hypothesis that different TIP isoforms may define different vacuole functions. Organelles labeled with these antibodies were also labeled with antipyrophosphatase antibodies, demonstrating that regardless of their size, they had the expected characteristics of vacuoles. Our results demonstrate that the storage vacuole tonoplast contains delta-TIP, protein storage vacuoles containing seed-type storage proteins are marked by alpha- and delta- or alpha- and delta- plus gamma-TIP, whereas vacuoles storing vegetative storage proteins and pigments are marked by delta-TIP alone or delta- plus gamma-TIP. In contrast, those marked by gamma-TIP alone have characteristics of lytic vacuoles, and results from other researchers indicate that alpha-TIP alone is a marker for autophagic vacuoles. In root tips, relatively undifferentiated cells that contain vacuoles labeled separately for each of the three TIPs have been identified. These results argue that plant cells have the ability to generate and maintain three separate vacuole organelles, with each being marked by a different TIP, and that the functional diversity of the vacuolar system may be generated from different combinations of the three basic types.  相似文献   
98.
Alternaria alternata , applied to run-off at 107 conidia ml -1 and given a 6 h dew period, caused an 88.5% reduction in dry weight of 4 to 5 true-leaf plants of Amaranthus retroflexus . This level of control was achieved whether the inoculated plants were grown in the glasshouse or outside. Formulation of the pathogen in oilseed rape emulsion reduced its dew period requirement from 24 h or more to 8 h or less. For example, with 106 conidia ml -1 , equivalent effects were found with 8 h dew with emulsion formulation compared to 48 h dew with the Tween formulation. Allowing spray deposits to dry on inoculated plants for ca 7 h, before exposing to dew increased the efficacy of the pathogen.  相似文献   
99.
100.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号