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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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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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A new genus and species of the subfamily Callodistomidae is described. The new genus is named Pirupalkia queulensis n. gen., and was found in the small intestine of the fish Cilus montti. This new genus, compared with other genus of the subfamily differs principally in the distribution of the vitellaria and location of the uterus.  相似文献   
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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   
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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   
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An attenuated live vaccine containing Babesia bovis and B. bigemina cultured in vitro with a serum-free medium was assessed for its clinical protection conferred of naïve cattle, under natural tick-challenge in a high endemicity zone to Babesia spp. Three groups of six animals were treated as follows: group I (GI) received a vaccine derived from parasites cultured with a free-serum medium; group II (GII) were immunized with the standard vaccine, with parasites cultured in a medium supplemented with 40% (v/v) bovine serum; and a control group (GIII) inoculated with non-infected bovine erythrocytes. Inocula were administered by IM route. Experimental animals were kept during 23 days after vaccination in a cattle farm free of ticks and Babesia spp. Thereafter, cattle were moved to a high endemicity farm for natural exposure to Babesia spp. transmitted by Rhipicephalus microplus ticks. Protection against clinical babesiosis was observed in bovines belonging to GI (100%) and GII (83.33%), while the control animals (GIII) were not protected, and showed severe clinical signs, closely related to babesiosis, were observed for at least three consecutive days during the challenge. These were fever, anemia, which were measured simultaneously, and circulating parasites were detected by optic light microscopy. All cattle showed B. bovis and B. bigemina in stained blood films during the challenge; B. bovis antibody titers were higher than those to B. bigemina in GI and GII, and lower titers were determined in GIII. The protective capacity of the vaccine derived from B. bovis and B. bigemina cultured in vitro in a serum-free medium was demonstrated.  相似文献   
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