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241.
242.
A long-acting prostaglandin F(2alpha) analogue, fenprostalene, was subcutaneously administered singly at doses of 5, 10, 25, 50, 100 or 150 microg on day 25 after ovulation during pregnancy in bitches (n=4 for each dosage), and maintenance of pregnancy, changes in plasma progesterone concentration, interval between the treatment and subsequent estrus and conception rate at that estrus were studied. Abortion was associated with a decrease in the plasma progesterone concentration below about 2 ng/ml, and the abortifacient effect was dose-dependent. Administration of 50 microg or more of fenprostalene induced abortion in all dogs 3 to 13 days after the treatment. The interval between administration and subsequent estrus was markedly shorter in the aborted bitches than in the non-aborted ones (P<0.01). The conception rate at the estrus in the aborted dogs was 50%, whereas all of the bitches who had not aborted became pregnant. The results indicate that a single administration of fenprostalene could induce abortion during mid-pregnancy in bitches, and the subsequent estrus may come early with a low conception rate.  相似文献   
243.
Natural tick infestations were assessed every 14 days on horses over a 2-year period. Amblyomma cajennense adult ticks were counted individually, without detachment from the horses. Larvae and nymphs of A. cajennense were collected using a rubber scraper that scratched engorged immature ticks from the host. Adult females of Anocentor nitens larger than 4mm length were counted on the horses. Blood samples were also obtained from the horses every 14 days and macroclimatic data were obtained for the study period. Infestations of A. cajennense demonstrated distinct peaks of activity for each of the three parasitic stages over each 12-month period, showing a 1-year generation pattern. Larvae predominated from April to July and nymphs from June to October. Adults predominated from October to March with a greater number of adult males than females. Although other studies on seasonal dynamics in the states of Rio de Janeiro and Minas Gerais were performed with the free-living stages of A. cajennense on pastures, the present study in the state of S?o Paulo, performed with the parasitic stages of A. cajennense on horses, showed similar results to those observed in other states. Infestations by A. nitens demonstrated distinct peaks of activity of adult females (>4 mm), suggesting different tick generations during the year. Infestation with A. nitens was much higher in the first year than the second year which may have been related to horse nutritional status and stocking rate. Although several climatic variables showed statistical significant correlation (r) with tick counts, the determination coefficients (R(2)) were always lower than 0.40, suggesting that any single significant variable (i.e. mean temperature) would not explain the tick distribution pattern over the year. The highest peaks of A. nitens females (>4 mm) were significantly associated with decrease in horse packed cell volumes (R(2)=0.603). The ears and the perineum, tail and groin region accounted for around 70% of all A. nitens females counted on the horses.  相似文献   
244.
In this study, we analyzed DNA sequence of mitochondrial DNA (mtDNA) control regions on the 130 native domestic pigs and eight wild boars in the mainland South and South-east Asian countries including Bhutan, Cambodia, Laos, Myanmar, and Vietnam. Forty-four haplotypes were found in the 138 individuals, 41 were in the domestic and four were in wild boars. Only one haplotype was shared by domestic and wild population in Bhutan. In other cases, mtDNA of wild boars did not show close affinity to that of the domestic pigs in the same location, indicating that the native domestic pigs in these countries did not originate in the present habitat. Phylogenetic analyzes of mtDNA haplotypes recapitulated several major clusters identified in other studies, but 11 haplotypes were grouped in a new cluster we named MTSEA. In most cases, more than one lineage group were present in a sampling station, indicating that the present indigenous domestic pigs may have multiple origins. The MTSEA haplotypes were present in relatively high frequencies in domestic pigs in the mountainous area of mainland South-east Asia (Cambodia and Laos), with a few found in Myanmar and Bhutan. The distributions of MTSEA haplotypes are in great conformity with the distribution of present-day Mon-Khmer language and indicated the existence of yet another independent domestication. The D2 haplotypes that distribute high frequency (almost 100%) throughout the Chinese breeds were dominant in Bhutan, Myanmar, and Vietnam. These results suggest an existence of human-mediated dispersal of domestic pigs from north to the south during the historical expansion of Sino-Tibetan and Tai peoples. The D3 haplotypes previously reported in north India were found in sympatric domestic and wild pigs in Bhutan. The D3 haplotype is an important proof of independent domestication event and/or great gene flow between wild and domestic pigs in the foot of Himalaya.  相似文献   
245.
246.
In the present study, the growth performance of a calf produced by mating a somatic cell cloned dam and sire was compared with that of its full siblings produced by mating the cattle used as nuclear donors for the cloned animals. The somatic cell cloned dam and sire were derived from cultured cumulus cells and ear cells, respectively. The cloned dam was artificially inseminated with semen from the cloned sire. A female calf was produced that was reared under general group feeding conditions. The calf was subjected to a clinical examination and to hematology, serum biochemistry, and telomere length analyses; all of these tests indicated that the calf was normal. The growth characteristics (body weight and shoulder height) of the calf fell within the range of the full siblings of the same sex produced by mating the animals used as the nuclear donors of clones. These findings suggest that the same breeding performance is expected from mating a cloned dam and sire as from mating the animals used as nuclear donors for the clones.  相似文献   
247.
The proportions of Sertoli cell tumor (SCT), seminoma and Leydig cell tumor in 50 dogs with unilateral testicular tumors were 52%, 36% and 12%, respectively. The rate of occurrence of SCT in the cryptorchid testis was very high (71%). The testicular superoxide dismutase (SOD) activity, testicular heat shock protein (HSP) 70 concentration and peripheral blood plasma inhibin (INH)-alpha concentration of 10 dogs with a unilateral cryptorchid testis and no testicular tumors, 10 dogs with SCT in a unilateral cryptorchid testis and 10 normal dogs, all aged 5-15 years, were measured in order to identify high risk factors for the occurrence of SCT in the canine cryptorchid testis. The mean SOD activity in cryptorchid testes and SCTs was significantly lower and higher, respectively, than in normal testes (both P<0.01). The mean HSP 70 concentration in both cryptorchid testes and SCTs was significantly higher than in normal testes (both P<0.01). The mean plasma INH-alpha concentration of the cryptorchid and SCT dogs was significantly lower and higher, respectively, than in normal dogs (P<0.05 and 0.01, respectively). The low SOD activity in the cryptorchid testis, low blood plasma INH-alpha concentration of the cryptorchid dogs and high HSP 70 concentration in the SCTs may be related to the occurrence of SCT and tumor cell proliferation in canine cryptorchid testes.  相似文献   
248.
Canine prostate cancer (cPCa) is a malignant neoplasm with no effective therapy. The BRAF V595E mutation, corresponding to the human BRAF V600E mutation, is found frequently in cPCa. Activating BRAF mutations are recognized as oncogenic drivers, and blockade of MAPK/ERK phosphorylation may be an effective therapeutic target against BRAF-mutated tumours. The aim of this study was to establish a novel cPCa cell line and to clarify the antitumor effects of MEK inhibitors on cPCa in vitro and in vivo. We established the novel CHP-2 cPCa cell line that was derived from the prostatic tissue of a cPCa patient. Sequencing of the canine BRAF gene in two cPCa cell lines revealed the presence of the BRAF V595E mutation. MEK inhibitors (trametinib, cobimetinib and mirdametinib) strongly suppressed cell proliferation in vitro, and trametinib showed the highest efficacy against cPCa cells with minimal cytotoxicity to non-cancer COPK cells. Furthermore, we orally administered 0.3 or 1.0 mg/kg trametinib to CHP-2 xenografted mice and examined its antitumor effects in vivo. Trametinib reduced tumour volume, decreased phosphorylated ERK levels, and lowered Ki-67 expression in xenografts in a dose-dependent manner. Although no clear adverse events were observed with administration, trametinib-treated xenografts showed osteogenesis that was independent of dosage. Our results indicate that trametinib induces cell cycle arrest by inhibiting ERK activation, resulting in cPCa tumour regression in a dose-dependent manner. MEK inhibitors, in addition to BRAF inhibitors, may be a targeted agent option for cPCa with the BRAF V595E mutation.  相似文献   
249.
The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species (P. elliotii, P. oocarpa, P. caribeae, P. merkusii, P. montezumae, and P. insularis) grown in Indonesia were investigated by GC and GC–MS. Generally, the amounts of extractive contents were higher in the inner bark than in the outer bark except for P. merksuii. Fatty acids, monoterpenes, sesquiterpenes, resin acids, triterpenoids, and steroids were detected and quantified. Inner and outer barks differed not only in content of these compounds but also in their composition. Fatty acids and alcohols were the major classes of lipophilic compounds in the outer bark of P. caribeae, P. insularis, and P. montezumae. Steroids and triterpenoids were the dominant compounds identified in the inner bark of P. elliotii, P. insularis, and P. merkusii. Resin acids were the most abundant group in the inner bark of P. oocarpa whereas monoterpenes and sesquiterpenes were recorded in minor quantities in both bark layers of all species.  相似文献   
250.
Moso bamboo (Phyllostachys pubescens) is cultivated for edible bamboo shoot production in Japan. Yamagata Prefecture is located in a heavy-snowfall region at the northern limit of the cultivated area. However, snow damage to bamboo culms occurs every year and decreases bamboo shoot production. “Uradome” is a treatment that involves cutting off the upper portion of the new culms when the bamboo shoot is almost fully grown. We studied the effect of “Uradome” implementation on incidence of snow damage to bamboo culms. In addition, we investigated terrain characteristics of bamboo forest at sites where snow damage occurred. As a result, the higher the degree of “Uradome” was, the lower the damage rate was. Furthermore, the results revealed that implementation of “Uradome” prevents snow damage to culms. It is considered that snow damage may be prevented by rendering the culm shape straight as a result of “Uradome”. The results also indicated that snow damage is more likely to occur on steep slopes. Factors that influence the incidence and severity of snow damage are considered to differ between Japan and other countries. Therefore, it is desirable to adopt preventative measures against snow damage, such as the “Uradome” method, irrespective of the local climate and terrain.  相似文献   
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