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   146篇
  免费   23篇
  2017年   2篇
  2016年   2篇
  2015年   2篇
  2014年   3篇
  2013年   26篇
  2012年   2篇
  2011年   5篇
  2009年   7篇
  2008年   2篇
  2007年   4篇
  2006年   2篇
  2005年   9篇
  2004年   3篇
  2002年   5篇
  2001年   2篇
  1999年   4篇
  1998年   3篇
  1997年   2篇
  1996年   4篇
  1992年   2篇
  1989年   3篇
  1987年   2篇
  1983年   2篇
  1975年   2篇
  1971年   2篇
  1925年   2篇
  1920年   1篇
  1918年   1篇
  1915年   6篇
  1914年   1篇
  1910年   1篇
  1909年   1篇
  1908年   1篇
  1905年   1篇
  1902年   1篇
  1901年   1篇
  1897年   2篇
  1892年   1篇
  1891年   1篇
  1889年   1篇
  1888年   1篇
  1887年   1篇
  1883年   3篇
  1882年   5篇
  1881年   2篇
  1880年   1篇
  1879年   6篇
  1878年   2篇
  1877年   2篇
  1876年   1篇
排序方式: 共有169条查询结果,搜索用时 15 毫秒
71.

Background  

Transmembrane (TM) proteins are proteins that span a biological membrane one or more times. As their 3-D structures are hard to determine, experiments focus on identifying their topology (i. e. which parts of the amino acid sequence are buried in the membrane and which are located on either side of the membrane), but only a few topologies are known. Consequently, various computational TM topology predictors have been developed, but their accuracies are far from perfect. The prediction quality can be improved by applying a consensus approach, which combines results of several predictors to yield a more reliable result.  相似文献   
72.
We developed 31 novel, polymorphic microsatellite loci in the marbled murrelet (Brachyramphus marmoratus), a critically endangered seabird. Variability was tested on 15 individuals from the Santa Cruz, California population, with each locus characterized by two to 12 alleles. Observed levels of heterozygosity ranged from 0.13 to 0.93. These loci provide a valuable means of assessing the population structure and demographic parameters of this species, which may be critical to its conservation across a fragmented habitat.  相似文献   
73.
74.
75.
76.
77.
78.
79.
80.
Cactus stems, the cladodes of Opuntia spp. cacti, are consumed in Mexico and other countries due to their fresh and herbaceous flavor, and because of their widely known nutraceutical benefits. In order to extend the postharvest life of this vegetable, the effect of a modified atmosphere packaging (MAP) was studied in cactus stems of the cultivar Atlixco stored at 4 ± 1 °C for 20 days under three types of atmospheres: (1) air (passive atmosphere), (2) 5 kPa O2 + 4 kPa CO2, and (3) N2. During storage, the titratable acidity decreased and the color of cladodes became darker and less green; however, the 5 kPa O2 + 4 kPa CO2 atmosphere was able to preserve both quality characteristics. All modified atmospheres reduced weight loss (from 8 to <2%) and the symptoms of chilling injury, and this physiological disorder appeared earlier in controls than in MAP-stored cladodes. The levels of fermentation metabolites were low in all three evaluated atmospheres. Because of this, only cladodes stored under the N2 atmosphere were selected for furthersensory analysis of the MAP effect on odor perception as evaluated by a trained panel. Results indicated that there was no detrimental effect (atypical odors) of MAP on this sensory characteristic. We conclude that cultivar Atlixco is suitable for preservation using MAP technology.  相似文献   
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