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21.
Crystalline lithocholic (3alpha-hydroxycholanic) acid was isolated from a pooled sample of feces from healthy men for the first time. This acid, which occurs in small amounts in human bile, was obtained by alcohol extraction, followed by solvent partition and chromatography. Under these conditions most of the acid was recovered in the form of its methyl ester.  相似文献   
22.
The direct ancestor of rice (Oryza sativa L.) is believed to be AA genome wild relatives of rice in Asia. However, the AA genome wild relatives involve both annual and perennial forms. The distribution of the retrotransposon p-SINE1-r2, a short interspersed nuclear element (SINE) at the waxy locus was analyzed in diverse accessions of the AA genome wild relatives of rice (O. rufipogon sensu lato). Most annual wild rice accessions had this retrotransposon, while most perennial types lacked this element, contradicting results to the previous studies. Results presented here suggest that O. sativa has dual origin that lead to indica-japonica differentiation. Results suggest the indica line of rice varieties evolved from the annual genepool of AA genome and the japonica varieties from the perennial genepool of AA genome wild rice.  相似文献   
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24.
Cryptorchidism is defined as the failure of the testis to descend into the scrotal position. Bulls with cryptorchidism have problems in both meat quality and husbandry management; thus, it is greatly important to accurately identify the retained testis and remove it during the early stage. Abdominal computed tomography (CT) was performed under general anesthesia in 34 bulls aged 3–9 months with cryptorchidism. All bulls underwent laparoscopic or incision approach for cryptorchidectomy, and 40 testes were dissected. The detection rates of retained testes were 64.5% in the abdominal cavity and 100% in the subcutaneous inguinal region, and the total detection rate was 72.5%. Furthermore, all cases in this study were suspected to have intra-abdominal cryptorchidism in primary care, but CT revealed that 22.5% of cases had cryptorchidism in the subcutaneous inguinal region. The CT value (mean ± standard deviation) of the retained testes was 20.96 ± 7.54 Hounsfield Unit, and the CT value and size of the retained testes showed a positive weak correlation with bovine age. Therefore, there is the demerit that general anesthesia and a huge device are necessary; nevertheless, CT is suggested to be useful in identifying the location of retained testes and selecting an appropriate surgical approach in bulls with cryptorchidism. Moreover, CT findings suggested that the maturation of the retained testes might depend not on the descending process but on age.  相似文献   
25.
This study examined the differences between non‐inoculated (control) corn and Northern Leaf Blight (NLB)‐damaged corn (inoculated corn); dry matter (DM) yield, silage fermentation quality, nutritive value and feed intake by sheep were compared. Leaf, stem and grain dry weights and gross yield of inoculated corn were significantly (P < 0.05) decreased compared with control corn. The contents of water‐soluble carbohydrate and nitrogen‐free extract (NFE) were decreased in inoculated corn compared with control corn. Silage made from both inoculated and control corn showed good fermentation quality. The digestibility of DM, organic matter, ether extract, NFE, and energy of silage made from inoculated corn were significantly (P < 0.05) lower, and contents of total digestible nutrients (TDN) and digestible energy (DE) were also significantly (P < 0.05) lower compared with silage made from the control corn. DM intake showed no significant discrepancy between the two types of silage. TDN and DE intakes from inoculated silage were significantly (P < 0.05) lower compared with control silage. From the above results it was shown that NLB caused a decrease in DM yield and NFE content in corn and a decrease in the nutritive value and feed intake of silage.  相似文献   
26.
We investigated the effect of oral administration of β-cryptoxanthin (β-CRX) on its serum concentration and peripheral neutrophil functions by the chemiluminescence (CL) response in Holstein cattle. A single oral administration of β-CRX was performed for serum β-CRX concentration (0, 0.05, 0.1, or 0.2 mg/kg body weight [BW]) and for peak CL response of peripheral neutrophils (0.2 mg/kg BW). The serum β-CRX concentration was peaked on 2 days after, similar to peak CL response on 3 days after β-CRX administration. Therefore, a single oral administration of β-CRX (0.2 mg/kg BW) induces higher serum concentration and concurrently enhances bactericidal ability of peripheral neutrophils in Holstein cattle.  相似文献   
27.
Accumulating data suggest a relationship between chemerin and energy metabolism. Our group previously described gene cloning, expression analysis and the regulatory mechanism of chemerin and its own receptor in mice and cattle. The objective of the present study was to investigate the physiological effect of chemerin on endocrine changes and energy metabolism in sheep using a biologically stable chemerin analog. The chemerin analog was intravenously administrated (100 or 500 µg/head) to sheep, and plasma insulin and metabolites (glucose, nonesterified fatty acids (NEFA), triglyceride, total cholesterol and high‐density lipoprotein (HDL) cholesterol) were analyzed. The chemerin analog dramatically increased the insulin levels, and glucose levels were decreased. NEFA levels were slightly decreased at 20 min but then increased gradually from 60 to 180 min after analog administration. In addition, injection of the chemerin analog immediately increased triglyceride and total cholesterol but not HDL levels. These results suggested that chemerin analog regulated insulin secretion related to glucose metabolism and the release of triglycerides in sheep in vivo. This study provides new information about endocrine and metabolic changes in response to chemerin in sheep.  相似文献   
28.
Oocyte maturation in mammals is characterized by a dramatic reorganization of the endoplasmic reticulum (ER). In mice, the ER forms accumulations in the germinal vesicle (GV) stage and distinctive cortical clusters in metaphase II (MII) of the oocyte. Multiple evidence suggests that this ER distribution is important in preparing the oocyte for Ca2+ oscillations, which trigger oocyte activation at fertilization. In this study, we investigated the time course and illustrated the possible functional role of ER distribution during maturation of porcine oocytes by immunostaining with protein disulfide isomerase (PDI). PDI forms clusters in the cytoplasm of oocytes. After immunostaining, PDI clusters were identified throughout the cytoplasm from the GV to metaphase I (MI) stage; however, at the MII stage, the PDI formed large clusters (1–2 µm) in the animal pole around the first polar body. PDI distribution was prevented by bacitracin, a PDI inhibitor. Our experiments indicated that, during porcine oocyte maturation, PDI undergoes a dramatic reorganization. This characteristic distribution is different from that in the mouse oocyte. Moreover, our study suggested that formation of PDI clusters in the animal pole is a specific characteristic of matured porcine oocytes.  相似文献   
29.
Seed dormancy contributes resistance to pre-harvest sprouting.Effects on respective quantitative trait loci (QTLs) for dormancy should be assessed by using fresh seeds before germinability altered through storage.We investigated QTLs related to seed dormancy using backcross inbred lines derived from a cross between Nipponbare and Kasalath.Four putative QTLs for seed dormancy were detected immediately after harvest using composite interval mapping.These putative QTLs were mapped near C1488 on chromosome 3 (qSD-3.1),R2171 on chromosome 6 (qSD-6.1),R1245 on chromosome 7 (qSD-7.1) and C488 on chromosome 10 (qSD-10.1).Kasalath alleles promoted dormancy for qSD-3.1,qSD-6.1 and qSD-7.1,and the respective proportions of phenotypic variation explained by each QTL were 12.9%,9.3% and 8.1%.We evaluated the seed dormancy harvested at different ripening stages during seed development using chromosome segment substitution lines (CSSLs) to confirm gene effects.The germination rates of CSSL27 and CSSL28 substituted with the region including qSD-6.1 were significantly lower than those of Nipponbare and other CSSLs at the late ripening stage.Therefore,qSD-6.1 is considered the most effective novel QTL for pre-harvest sprouting resistance among the QTLs detected in this study.  相似文献   
30.
Localization patterns of lipid droplets in the cytoplasm of porcine oocytes were evaluated as a novel marker for in vitro maturation (IVM) of oocytes with high developmental competence. Porcine oocytes were cultured in TCM-199, which is a complete synthetic medium, for 44 h at 38.5 C. Localization patterns were divided into 2 classes: lipid droplets localized uniformly in the whole cytoplasm (class I) and those that were centrally located (class II). After IVM in TCM-199, 60% of matured oocytes exhibited the class II pattern. To investigate the relation between the distribution of lipid droplets and the developmental rate of the oocyte, the developmental rates of class I and class II oocytes were compared after in vitro fertilization (IVF). Class II oocytes showed a significantly higher rate of blastocyst development than class I oocytes. These results suggest that porcine oocytes with high developmental competence can be selected based on the localization patterns of lipid droplets.  相似文献   
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