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Recombinant inbred strains of mice were used to localize the genes coding for the class alpha glutathione S-transferase 2 (Gst-2). The genes showed three distinct strain distribution patterns, indicating that they occur in at least three clusters separable by recombination. All three clusters are located in the vicinity of the d locus on mouse chromosome 9, but two of them are closer to d than the third. Linked to Gst-2 on mouse chromosome 9 are two enzyme-encoding loci, Pgm-3 and Mod-1. The human counterparts of Gst-2, Pgm-3, and Mod-1 map to 6p12, 6q12, and 6q12, respectively. Thus, the pericentric region of human chromosome 6 has its homolog in the segment spanning Gst-2, Pgm-3, and Mod-1 on mouse chromosome 9. The fact that the syntenic group extends across the centromere of human chromosome 6 can best be explained by a pericentric inversion postulated to have taken place in the primate lineage leading to Catarhini. 相似文献
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Guillermo Figueroa Miriam Troncoso Cristián López Patricia Rivas Magaly Toro 《BMC microbiology》2009,9(1):94
Background
Thermotolerant Campylobacter is among the more prevalent bacterial pathogens that cause foodborne diseases. This study aimed at evaluating the occurrence of thermotolerant Campylobacter contamination in chicken carcasses and processing plant stations (chilling water, scalding water, defeathering machinery, evisceration machine, and transport crates) in two of the Chilean main slaughterhouses. In addition, the isolation rates of thermotolerant Campylobacter during evisceration and following chiller processing were compared. 相似文献6.
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R Caviedes H R Croxatto J Corthorn C Figueroa K Salas 《Cell biology international reports》1987,11(10):735-743
Cortical tubular cultures enriched with distal segments were prepared from the kidney of adult Fisher 344 rats bearing thyroid tumors. After two years of cultivation (20 passages) cell monolayers contained immunocytochemically detectable cytokeratin and kallikrein material in their cytoplasm. Furthermore cell pellets showed a true renal type of kininogenase activity corresponding to active kallikrein which ranged from 22.3 to 1.5, and total Kallikrein from 29.9 to 2.8 pg kinins/min per mg of protein. 相似文献
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G Yarrington K Fontwit J P Figueroa A Massmann P W Nathanielsz 《The Yale journal of biology and medicine》1986,59(4):415-424
Cervical and uterine electromyograms (EMG) have been recorded from ovariectomized non-pregnant ewes. When the animals were infused with saline, the frequency of EMG events lasting less than 180 seconds was not different from those lasting more than 180 seconds. During infusion of estradiol at 100 micrograms X 24 hours-1 into the maternal jugular, the frequency of events less than 180 seconds increased significantly in the myometrium and in the cervix. Contracture activity (events lasting more than 180 seconds) was not significantly different in the myometrium compared to the cervix before estradiol administration. During estradiol infusion, the contracture activity remained unchanged. During 4-amino-antipyrine (4AA) administration, the contracture activity decreased significantly in the myometrium, while an insignificant change occurred in the cervix. This state was associated with a decrease in the venous PGFM:6-keto F1 alpha plasma ratio. Infusion of PGF2 alpha (.5 micrograms min-1 and 1.0 microgram X min-1 for ten minutes) into the femoral artery resulted in a significant increase in the frequency of events less than 180 seconds in both the myometrium and cervix. For the duration of the ten-minute infusion, the activity was contracture-like. These findings suggest that the cervix may not only be influenced by mechanical properties (stretch) and local paracrine factors but also by various stimulators and inhibitors irrespective of the myometrium. 相似文献
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M. V. Achi J. M. Figueroa V. González Nicolini M. J. Villar J. H. Tramezzani 《Cell and tissue research》1995,281(2):375-378
The presence and distribution of peptidergic nerve fibers were studied in the testis and mesorchium of the toad by means of immunohistochemistry. Cryostat sections of the testis and whole-mount preparations of mesorchia were immunostained with antisera to calcitonin gene-related peptide (CGRP) and neuropeptide tyrosine (NPY). After leaving the mesorchium CGRP-immunoreactive (IR) fibers were seen predominantly running in between the seminiferous tubules. In addition, a small population of CGRP-IR nerve fibers formed thin plexuses around blood vessels. Conversely, NPY-like immunoreactivity predominated in nerve fibers that formed dense plexuses around vessels both in the mesorchium and testis. Additionally, some single NPY-IR nerve fibers could be seen in both structures studied. The functional significance of these peptidergic systems in the testis of the toad remains to be analyzed. 相似文献