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161.
162.
MP Lisovoi NM Lesovoy GI Vasechko 《Archives Of Phytopathology And Plant Protection》2013,46(2):123-127
A new method of selection of the winter wheat varieties has been tested for resistance to the pest insects' complex by the traits of plants that are the markers of plant resistance. It makes it possible to use this method from year to year independently of the pests' density. 相似文献
163.
Crustacean and cheliceratan hemocyanins (oxygen-transport proteins) and
insect hexamerins (storage proteins) are homologous gene products, although
the latter do not bind oxygen and do not possess the copper- binding
histidines present in the hemocyanins. An alignment of 19 amino acid
sequences of hemocyanin subunits and insect hexamerins was made, based on
the conservation of elements of secondary structure observed in X-ray
structures of two hemocyanin subunits. The alignment was analyzed using
parsimony and neighbor-joining methods. Results provide strong indications
for grouping together the sequences of the 2 crustacean hemocyanin
subunits, the 5 cheliceratan hemocyanin subunits, and the 12 insect
hexamerins. Within the insect clade, four methionine- rich proteins, four
arylphorins, and two juvenile hormone-suppressible proteins from
Lepidoptera, as well as two dipteran proteins, form four separate groups.
In the absence of an outgroup sequence, it is not possible to present
information about the ancestral state from which these proteins are
derived. Although this family of proteins clearly consists of homologous
gene products, there remain striking differences in gene organization and
site of biosynthesis of the proteins within the cell. Because studies on
18S and 12S rRNA sequences indicate a rather close relationship between
insects and crustaceans, we propose that hemocyanin is the ancestral
arthropod protein and that insect hexamerins lost their copper-binding
capability after divergence of the insects from the crustaceans.
相似文献
164.
Kemal?O. Yariz Duygu Duman Celia?Zazo Seco Julia Dallman Mingqian Huang Theo?A. Peters Asli Sirmaci Na Lu Margit Schraders Isaac Skromne Jaap Oostrik Oscar Diaz-Horta Juan?I. Young Suna Tokgoz-Yilmaz Ozlem Konukseven Hashem Shahin Lisette Hetterschijt Moien Kanaan Anne?M.M. Oonk Yvonne?J.K. Edwards Huawei Li Semra Atalay Susan Blanton Alexandra?A. DeSmidt Xue-Zhong Liu Ronald?J.E. Pennings Zhongmin Lu Zheng-Yi Chen Hannie Kremer Mustafa Tekin 《American journal of human genetics》2012,91(5):872-882
165.
166.
Ultimate tensile strength of fetal and adult human tendons 总被引:1,自引:0,他引:1
167.
This investigation was undertaken to determine the densities of fresh human compact and cancellous bone, with its marrow constituents intact, and compact and cancellous bone taken from embalmed cadavers. The density of 107 bone specimens was determined on the basis of the weight and volume of each specimen. Mean density results were: (1) fresh compact bone, 1.85; (2) fresh cancellous bone, 1.08; (3) embalmed compact bone, 1.85; and (4) embalmed cancellous bone, 1.09. Embalming did not appear to have altered the density of either compact or cancellous bone. It was observed also that the densities of several bone specimens taken from the same area of one bone varied greatly. 相似文献
168.
169.
Boundary elements or insulators subdivide eukaryotic chromosomes into a series of structurally and functionally autonomous domains. They ensure that the action of enhancers and silencers is restricted to the domain in which these regulatory elements reside. Three models, the roadblock, sink/decoy, and topological loop, have been proposed to explain the insulating activity of boundary elements. Strong predictions about how boundaries will function in different experimental contexts can be drawn from these models. In the studies reported here, we have designed assays that test these predictions. The results of our assays are inconsistent with the expectations of the roadblock and sink models. Instead, they support the topological loop model. 相似文献
170.