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71.
In several primates and carnivores, pronation/supination angles of the forearm skeleton were examined, and it is thought that a larger angle is useful to acquire dexterous behaviors in feeding and/or life style, including climbing. In this study, the pronation/supination angles in Asiatic black, brown and polar bears were nondestructively examined. These specimens were classified as adult or non-adult. Three or four carcasses of each group of Asiatic black and brown bears were used for CT analysis, whereas only one adult polar bear was used. The forearms were positioned within the gantry of a CT scanner in both maximally supinated and pronated states. Extracted cross-sectional CT images of two positions were superimposed by overlapping the outlines of each ulna. The centroids of the radii were detected, and then the centroid of each radius and the midpoint of a line which connects between both ends of the surface of each radius facing the ulna, were connected by lines to measure the angle of rotation as an index of pronation/supination. In adult brown and polar bears, the angles were smaller as compared with the other groups (Asiatic black and non-adult brown bears). Asiatic black and non-adult brown bears can climb trees, whereas adult brown bears and polar bears cannot. This suggests that the pronation/supination angle is related to arboreal activity in Ursidae.  相似文献   
72.
The ecology of shiga‐toxigenic Escherichia coli (STEC) is important in the animal production environment. We investigated fecal shedding of STEC in one town in Miyagi, Japan by multiplex polymerase chain reaction (PCR) targeting shiga toxin gene 1 (stx1), gene 2 (stx2) and malB promoter gene, and analyzed the PCR products of stx1 or stx2 (54 samples) by direct sequencing. Three of 46 (6.5%) beef cattle in the University Farm of Tohoku University (Kawatabi Farm) and 11 of 70 (15.7%) calves in neighboring dairy farms carried STEC. Rate of detecting genes of stx1, stx2 and stx1+2 was 3.4% (4/116), 8.6% (10/116) and 0.9% (1/116), respectively. Serotyping indicated that STEC contaminated farms at different times or through different routes. Isolates harbored no mutation among stx1, but six (Kawatabi Farm) and 38 (neighboring farms) base substitutions among stx2, respectively. The diversity of substitutions of stx2 was observed among farms or even in a farm. Phylogenic analysis revealed that STEC detected in the area were classified into three clusters by the variety of stx2. Sequence analysis of stx2 will be one of the tools for clarifying the source of outbreaks and the route of contamination of STEC.  相似文献   
73.
This study was designed to examine the effects of the proportion of concentrate in the diet on the secretion of growth hormone (GH), insulin and insulin‐like growth factor‐I (IGF‐I) secretion and the GH‐releasing hormone (GHRH)‐induced GH response in adult sheep fed once daily. Dietary treatments were roughage and concentrate at ratios of 100:0 (0% concentrate diet), 60:40 (40% concentrate diet), and 20:80 (80% concentrate diet) on a dry matter basis. Mean plasma concentrations of GH before daily feeding (10.00–14.00 hours) were 11.4 ± 0.4, 10.1 ± 0.5 and 7.5 ± 0.3 ng/mL on the 0, 40 and 80% concentrate diet treatments, respectively. A significant decrease in plasma GH concentration was observed after daily feeding of any of the dietary treatments and these decreased levels were maintained for 8 h (0%), 12 h (40%) and 12 h (80%), respectively (P < 0.05). Plasma IGF‐I concentrations were significantly decreased 8–12 h and 4–16 h after the end of feeding compared with the prefeeding level in the 40 and 80% concentrate diet treatments, respectively (P < 0.05). GHRH injection brought an abrupt increase in the plasma GH concentrations, reaching a peak 10 min after each injection, but, after the meal, the peak plasma GH values for animals fed 40% (P < 0.05) and 80% (P < 0.01) concentrate diet were lower than that for roughage fed animals. The concentrate content of a diet affects the anterior pituitary function of sheep resulting in reduced baseline concentrations of GH and prolonged GH reduction after feeding once daily.  相似文献   
74.
Adipose tissue is an important organ that is involved in the peripheral regulation of body homeostasis, specifically, energy intake, storage and expenditure. Since fat metabolism is of the utmost importance in ruminants, the signals and mechanisms which regulate adiposity for fattening have been studied and characterized by many different approaches. Adipogenesis in the adipose tissues of ruminants is triggered and modulated by several factors/genes, some of which (conjugated linoleic acid, tumor necrosis factor‐α and adipogenin) have been examined with respect to adipogenesis in ruminants by numerous researchers, including those in our group. The purpose of this article was to describe recent advances and insights into the molecular regulating processes of preadipocyte, adipocyte and adipose tissues in ruminants.  相似文献   
75.
The effect of the antitumor drug, methotrexate (MTX), which is applied to brain tumors, is restricted by the blood-brain barrier (BBB), which is composed of P-glycoprotein (P-gp) and multidrug resistance associated protein (MRP). We, therefore, studied if a potent P-gp and MRP modulator, cyclosporin A (CysA), can modulate the MTX concentration in the rat brain. If it can, which route is more effective, intravenous or intrathecal? We intravenously or intrathecally administered MTX to rats with or without CysA. After 6 hr, brains and cerebrospinal fluid (CSF) were sampled, and their MTX concentrations were compared. Each MTX concentration was determined by high-performance liquid chromatography with UV detection. CysA had no significant affect on the MTX concentration in the brain or CSF when MTX was intravenously injected. In contrast, when MTX was intrathecally administered, CysA had a larger effect on the MTX concentration in the brain than in the CSF. This indicates CysA potentiated the brain MTX concentration when MTX was intrathecally administered. It is suggested that CysA did not potentiate the distribution of MTX from blood into the brain, but instead potentiated the distribution of MTX from CSF into the brain. Since chemicals in CSF generally diffuse into the brain easily, CysA probably inhibited the excretion of MTX from the brain. This could be caused by inhibition of P-gp or MRP at the BBB. Therefore, CysA can be a useful tool to achieve an appropriate MTX concentration in brain.  相似文献   
76.
Currently, no simple assays are available for routine quantitative detection of Escherichia coli-produced Shiga toxin 2e (Stx2e) that causes porcine edema disease. Here, we present a novel quantitative detection method for Stx2e based on the measurement of Stx2e binding to the specific globotetraosylceramide (Gb4) receptor by ELISA (Gb4-ELISA). No cross-reactivity was found with the other Shiga toxins Stx1 and Stx2, indicating high specificity. When the recombinant Stx2e B subunit (Stx2eB) was used, the absorbance measured by Gb4-ELISA increased linearly with Stx2eB concentration in the range of 20–2,500 ng/ml. The Gb4-ELISA method can be easily performed, suggesting that it would be a useful diagnostic tool for porcine edema disease.  相似文献   
77.
Hepatitis E virus (HEV) is known as a causative agent of zoonosis and food poisoning. Pigs and some species of wild animals, including wild boar, are known to be a reservoir of HEV. In this study, we investigated the situation regarding HEV infection in wild boars in Ibaraki Prefecture, Japan. Serum, liver and feces samples from 68 animals were collected, and the presence or absence of HEV genomic RNA and HEV antibodies were analyzed. The viral genome was detected in samples from 7 (10.3%) animals, with all HEVs classified as genotype 3, subtype 3b. HEV antibodies were detected in samples from 28 (41%) animals. This report demonstrates for the first time the high prevalence of HEV infection in wild boars in Ibaraki Prefecture.  相似文献   
78.
对中国内蒙古自治区饲育马土壤环境中马红球菌的分布知之甚少;为此,在中国内蒙古通辽近郊、内蒙古南部锡林郭勒盟大草原、内蒙古东部呼伦贝尔大草原等马场共收集了108份土壤样品进行了马红球菌的检测。结果,锡林郭勒盟大草原和呼伦贝尔大草原的马红球菌分离率为25.9%~30.0%,通辽近郊土壤中分离率高达82.3%。这说明在通辽近郊马红球菌的分离菌数是草原土壤中马红球菌分离菌数的10倍。应用PCR技术检测了488株的毒力相关基因,相对分子质量分别为15000~17000(VapA)和20000(VapB)。所有的分离株都未检出毒力相关基因。这些无毒力分离株的质粒资料显示,各种大小的潜在质粒的发生率为13.3%~21.5%。本研究结果截然不同于我们新近对蒙古国的调查结论:马红球菌在蒙古国乌兰巴托的马群中不存在。造成这一差异的原因可能在于蒙古国的游牧生活和内蒙古的非游牧生活。  相似文献   
79.
When a large-scale epidemic of porcine epidemic diarrhea (PED) occurred in 2013 in Japan, feedback feeding (feeding feces and gut tissues of infected piglets) was attempted to impart immunity to sows and immunize nursing piglets via breastfeeding. This study evaluated the effect of feedback feeding on PED control at 172 farms in Kagoshima and Miyazaki Prefectures. Univariable and multivariable generalized linear models were used to analyze the associations between conduct of feedback feeding and damage from the outbreak (outbreak period and the number of piglet deaths) at the farm level. The within-farm outbreak period shortened over time after the regional outbreak began on Kyushu Island (P=0.009) and was longer on large-scale farms (mean 66.0 days, P=0.003) than small-scale farms (29.4 days) and on farms that used feedback feeding (145.2 days, P=0.059) than those that did not (66.0 days). The number of dead piglets decreased over time since the first regional case (P<0.001) and was higher at farrow-to-finish farms (3.8 piglets/sow, P<0.001) than reproduction farms (0.7 piglets/sow). The effect of feedback feeding on the number of dead piglets was not significant, but its interaction term with farm style had a significant effect (5.0 more piglet deaths at reproduction farms than fallow-to-finish farms, P=0.001). These results suggest that feedback feeding made the damage from PED worse, though it was well established at a later stage of the regional PED epidemic.  相似文献   
80.
The size of canine focal liver lesions (FLLs) is known to be one of the predicting criteria for malignancy. However, there are discrepancies for the measurement of maximum lesion size, resulting in contradicting results among studies and incidences of false positive outcomes. Thus far, the morphometric changes of FLLs for distinguishing malignancy from benignancy remains undocumented. This study aimed to investigate morphometric characteristics of FLLs using computed tomography (CT). CT images of 40 dogs with histopathological confirmation of 49 liver lesions, including 39 hepatocellular carcinomas and 10 nodular hyperplasias were retrospectively reviewed. The morphometric parameters including size (long and short axis diameters measured on transverse image), shape (measured by long to short axis (L/S) ratio), volume, and surface appearance of a liver lesion were evaluated using univariate and stepwise multivariate analyses, respectively. The results of univariate analysis showed that long and short axis diameters, L/S ratio, volume, and surface appearance of a lesion were significantly different between hepatocellular carcinomas and nodular hyperplasias. Multivariate analysis revealed that short axis diameter (>3.30 cm; odds ratio (OR): 36.1, 95% confidence interval (CI): 3.36–387.05, P=0.0031) and L/S ratio (>1.23; OR: 18.1, 95% CI: 1.61–205.12, P=0.0191) were independent predictors of malignancy, with the area under the curve of 0.9154. These results suggest that the combination of short axis diameter and L/S ratio is a promising tool for predicting liver malignancy with outstanding discriminating ability.  相似文献   
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