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991.
J Chae M J Kim J H Goo S Collier D Gubb J Charlton P N Adler W J Park 《Development (Cambridge, England)》1999,126(23):5421-5429
The tissue polarity genes control the polarity of hairs, bristles and ommatidia in the adult epidermis of Drosophila. We report here the identification of a new tissue polarity gene named starry night (stan). Mutations in this essential gene alter the polarity of cuticular structures in all regions of the adult body. The detailed polarity phenotype of stan on the wing suggested that it is most likely a component of the frizzled (fz) pathway. Consistent with this hypothesis, stan appears to be downstream of and required for fz function. We molecularly cloned stan and found that it encodes a huge protocadherin containing nine cadherin motifs, four EGF-like motifs, two laminin G motifs, and seven transmembrane domains. This suggests that Stan functions in signal reception, perhaps together with Fz. 相似文献
992.
993.
S. N. Perova 《Inland Water Biology》2008,1(4):371-379
The macrozoobenthos taxonomic composition in small karst lakes of Vladimir oblast is studied for the first time. In the structure
of bottom communities, 149 taxa one rank below the genus have been found. Chironomid larvae and other amphibiotic animals,
as well as oligochaetes, prevail. Most of them are species widely distributed in the surface waters of European Russia. The
highest macrozoobenthos species diversity was recorded in neutral lakes, and the lowest diversity was in lakes with weakly
acidic waters. 相似文献
994.
Yu. S. Ravkin S. M. Tsybulin S. G. Livanov K. V. Toropov V. N. Kuranova V. P. Starikov S. V. Chesnokova 《Contemporary Problems of Ecology》2008,1(5):568-573
For the entire territory of West Siberia, including its plain and mountainous parts, two maps were constructed for populations of amphibians together with reptiles, and of birds. Communities of these classes of vertebrates differ from one another in their spatial differentiation. The differences are demonstrated for the plain and mountainous territories considered jointly and separately. 相似文献
995.
996.
997.
998.
999.
N A Grekova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1978,(8):109-112
Lysozyme content was determined in the subcutaneous cellular tissue of guinea pigs and albino rats differing by species resistance to brucella infection. Experiments were conducted on intact animals and those inoculated subcutaneously with live Br. abortus 19-BA vaccine. Connective tissue was taken from the site of the vaccine administration and from the contralateral side (control). Observations showed connective tissue of the animals highly sensitive to brucella infection to be exceedingly poor in this enzyme; as to connective tissue of albino rats with low sensitivity--it contained high amount of this enzyme. Lysozyme content increased considerably in the animals belonging to both species in the inflammatory focus developing at the site of the vaccine inoculation. 相似文献
1000.
Meta‐analyses evaluating the association between the serotonin transporter polymorphism (5‐HTTLPR) with neuroticism and depression diagnosis as phenotypes have been inconclusive. We examined a gene–environment interaction on a cognitive vulnerability marker of depression, cognitive reactivity (CR) to sad mood. A total of 250 university students of European ancestry were genotyped for the 5‐HTTLPR, including SNP rs25531, a polymorphism of the long allele. Association analysis was performed for neuroticism, CR and depression diagnosis (using a self‐report measure). As an environmental pathogen, self‐reported history of childhood emotional abuse was measured because of its strong relationship with depression. Participants with the homozygous low expressing genotype had high CR if they had experienced childhood emotional maltreatment but low CR if they did not have such experience. This interaction was strongest on the Rumination subscale of the CR measure. The interaction was not significant with neuroticism or depression diagnosis as outcome measures. Our results show that 5‐HTTLPR is related to cognitive vulnerability to depression. Our findings provide evidence for a differential susceptibility genotype rather than a vulnerability genotype, possibly because of the relatively low levels of abuse in our sample. The selection of phenotype and environmental contributor is pivotal in investigating gene–environment interactions in psychiatric disorders. 相似文献