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In order to evaluate the physiological roles of the testicular endothelin (Edn) signaling via Edn receptor subtype-A (Ednra) in mammals, the localization of Ednra was investigated by in situ hybridization and immunohistochemistry in the testis of rats, dogs, and monkeys. For in situ hybridization, a rat Ednra RNA probe which is highly homologous to the subcloned canine and monkey Ednra (88.7% and 87.9% identical, respectively) was used. Both Ednra mRNA and protein were detected in interstitial cells and cells in the basal compartment of the seminiferous tubules, mainly Sertoli cells, as well as spermatogonia and some early spermatocytes, but not spermatids. The localization pattern of Ednra was exhibited in a same manner among species, indicating that the physiological role of Edn signaling throughout Ednra was maintained in the mammalian testis.  相似文献   
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Gene expressions and their interaction are complex and have not been definitely clarified in the placenta. To identify interactions of gene products previously not studied, we applied cDNA subtraction analyses to the placenta between days 12 and 16, days 12 and 14, days 14 and 16 of pregnancy. Among subtracted cDNAs cathepsin M, Q and R in PECs were specifically identified on days 14 and 16 pregnancy. All of these gene expressions exhibited a similar pattern to the mPL-II gene expression determined by northern blot and RT-PCR analyses. By means of in situ hybridization, these mRNAs were localized in the basal and labyrinth zones of the placenta on day 16 of pregnancy. Double staining studies of cathepsin Q or cathepsin R mRNA by in situ hybridization followed by immunohistochemical staining of mPL-II in the same section revealed that signals for cathepsin Q and cathepsin R mRNAs were colocalized in mPL-II immunopositive trophoblast cells in the basal and labyrinth zones of the placenta on day 16 of pregnancy. Possible association of cathepsins with mPL-II may play important roles in placental functions during the latter half of pregnancy in mice.  相似文献   
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The prevalence of Babesia (Theileria) equi and B. caballi infections in donkeys in western Xinjiang China was investigated. In total, 93 serum samples were randomly taken from donkeys in the Kashi and Ili areas, and examined for B. equi and B. caballi infections by enzyme-linked immunosorbent assays using recombinant antigens. Of the 93 samples, 9 (9.6%) and 36 (38.7%) samples were positive for B. equi infection and B. caballi infection, respectively. In addition, 2 (2.2%) samples were positive for both B. equi and B. caballi infections. These results indicate that equine babesiosis might be extensively prevalent in donkeys in western Xinjiang.  相似文献   
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Abundance indices (AIs) provide information on population abundance and trends over time, while AI variance (AIV) provides information on reliability or quality of the AI. AIV is an important output from surveys and is commonly used in formal assessments of survey quality, in survey comparison studies, and in stock assessments. However, uncertainty in AIV estimates is poorly understood and studies on the precision and bias in survey AIV estimates are lacking. Typically, AIV estimates are “design based” and are derived from sampling theory under some aspect of randomized samples. Inference on population density in these cases can be confounded by unaccounted process errors such as those due to variable sampling efficiency (q). Here, we simulated fish distribution and surveys to assess the effect of q and variance in q on design‐based estimates of AIV. Simulation results show that the bias and precision of AIV depend on the mean q and variance in q. We conclude that to fully evaluate the reliability of AI, both observation error and variability in q must be accounted for when estimating AIV. A decrease in mean q and an increase in the variance in q results in increased bias and decreased precision in survey AIV estimates. These effects are likely small in surveys with mean q ≥ 1. However, for surveys where q ≤ 0.5, these effects can be large. Regardless of the survey type, AIV estimates can be improved with knowledge of q and variance in q.  相似文献   
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Blood samples from 78 cattle were tested for hemoplasma infection using molecular methods. PCR and sequence analysis revealed that 17 cattle were infected with Mycoplasma wenyonii, while 13 were infected with 'Candidatus Mycoplasma haemobos'. Four animals were infected with both species. This is the first study to report hemoplasma species infection among cattle in Japan.  相似文献   
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Neospora caninum was isolated from a naturally infected sheep from Brazil by bioassay in dogs. Approximately 70g of brain from each of two 4-month-old sheep with indirect fluorescent antibodies (>or=1:50) to N. caninum was offered to a different IFAT negative dog (Sheep n. 302, IFAT 1:400-Dog 1 and Sheep n. 342, IFAT 1:50-Dog 2). Parasite DNA was detected in both sheep brains using a PCR targeting the Nc-5 gene of N. caninum. Shedding of Neospora-like oocysts was noticed only in Dog 1, from 10 days post-inoculation (PI) to 25 days PI (a total of approximately 27,600 oocysts). Seventy days after infection, Dog 1 was euthanized and brain/cerebellum and medulla were collected and submitted to molecular methods, as were the oocysts, to confirm the identity of the isolate. Serum samples collected weekly from both dogs from the infection to the end of the experimental period had no antibodies anti-N. caninum by IFAT (<1:50). Oocysts, brain/cerebellum and medulla specimens of Dog 1 proved positive by a PCR assay targeting the Nc-5 gene of N. caninum. In addition, the oocysts have the DNA amplified by a PCR based on primers directed to the common toxoplasmatiid ITS1 sequence. The PCR products of ITS1 were sequenced, confirming again the isolate as N. caninum. Oocysts were also orally inoculated in two Swiss white mice two Mongolian gerbils (Meriones ungulatus) and two large vesper mice (Calomys callosus) (10(3)oocysts/animal). The rodents were sacrificed 2 months PI, and fresh preparations of brains showed Neospora thick-walled cysts in gerbil brains, but molecular detection using the Nc-5 PCR assay revealed DNA parasite in gerbil and also C. callosus brains. This is the first report of isolation and sequencing of N. caninum from a Brazilian sheep and the first report of molecular detection of N. caninum from C. callosus.  相似文献   
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