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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   
2.
Density separations show great promise in elucidating the progression of organic matter decomposition and mineral association in soils. We review the literature on these separations, with a focus on the low-density material released by sonication, the so-called "occluded", "aggregate-protected" or mineral-associated low-density fraction (m-LF). This fraction accounts for up to half of the total C in surface soils. A commonly cited model explains this material as an intermediary (between mineral-free LF and high-density fractions) during the progressive decay of plant detritus accompanied by mineral association. However, the great variance in m-LF compositions (e.g. unusual aliphaticity, high C:N, variable mean residence time) shown in the literature implies a separate genesis for some of the organic matter in this fraction in some soils. Aspects of organic particle size and lipid composition of original plant sources deserve more attention. We propose a revision of the current model that allows for materials of widely varying lability in this pool. A combination of density separation with isotope tracers, detailed chemical characterization and other physical separation techniques are needed to improve models of soil organic matter dynamics linking the density fractions.  相似文献   
3.
用声强法对木工带锯机空转噪声特性的测量分析   总被引:1,自引:0,他引:1  
使用声强法对木工带锯机的噪声特性进行了测量,测得三面的声强值和噪声的矢量图、等高线图、三维图,由这些数据和线图可以全面了解带锯机的噪声分布情况,以便分析和控制噪声。  相似文献   
4.
The structure and functions of placentas were examined in 3 species of rorqual whales, common minke (Balaenoptera acutorostrata), Bryde’s (B. brydei) and sei (B. borealis) whales, with the aim of confirming the structural characteristics of the chorion, including the presence of the areolar part, and clarifying steroidogenic activities and fetomaternal interactions in the placentas of these whales. Placentas were collected from the second phase of the Japanese Whale Research Program under Special Permit in the North Pacific (JARPN II). Histological and ultrastructural examinations revealed that these whale placentas were epitheliochorial placentas with the interdigitation of chorionic villi lined by monolayer uninucleate cells (trophoblast cells) and endometrial crypts as well as folded placentation by fold-like chorionic villi. Moreover, well-developed pouch-like areolae were observed in the placentas, and active absorption was suggested in the chorionic epithelial cells of the areolar part (areolar trophoblast cells). Berlin blue staining showed the presence of ferric ions (Fe3+) in the uterine glandular epithelial cells and within the stroma of chorionic villi in the areolar part. An immunohistochemical examination revealed tartrate-resistant acid phosphatase (TRAP; known as uteroferrin in uteri) in the cytoplasm of glandular cells and areolar trophoblast cells. This result suggested that, in cetaceans, uteroferrin is used to supply iron to the fetus. Furthermore, immunoreactivity for P450scc and P450arom was detected in trophoblast cells, but not in areolar trophoblast cells, suggesting that trophoblast cells synthesize estrogen in whale placentas. Therefore, we herein immunohistochemically revealed the localization of aromatase and uteroferrin in cetacean placentas during pregnancy for the first time.  相似文献   
5.
In July 2000, a bacterial wilt was found on China aster (Callistephus chinensis Nees) on Hokkaido, Japan. Bacteriological characteristics of the isolated bacteria were identical to Erwinia chrysanthemi. This is the first report on bacterial wilt of China aster caused by E. chrysanthemi. Received 4 June 2001/ Accepted in revised form 6 September 2001  相似文献   
6.
Repro34 is an N-ethyl-N-nitrosourea (ENU)-induced mutation in mice showing male-specific infertility caused by defective spermatogenesis. In the present study, we investigated pathogenesis and molecular lesions in relation to spermatogenesis in the repro34/repro34 homozygous mouse. Histological examination of the testis showed that the seminiferous epithelium of the repro34/repro34 mouse contained spermatogonia and spermatocytes but no round and elongating spermatids. Instead of these haploid cells, multinucleated giant cells occupied the niche of the seminiferous tubules. Immunohistochemical staining for Hsc70t, an elongating spermatid specific protein, confirmed the absence of elongating spermatids. Furthermore, RT-PCR showed that there were significantly reduced expressions of the marker genes specifically expressed in the spermatid and that there was no difference in the expressions of the spermatocyte specific marker genes. These findings indicated interruption of the spermatogenesis during transition from the spermatocyte to spermatid in the repro34/repro34 mouse. The repro34 locus has been mapped on a 7.0-Mb region of mouse chromosome 5 containing the Syntaxin 2/Epimorphin (Stx2/Epim) gene, and targeted disruption of this gene has been reported to cause defective spermatogenesis. We therefore sequenced the entire coding region of the Stx2/Epim gene and found a nucleotide substitution that results in a nonsense mutation of this gene. The expression pattern of the Stx2/Epim gene during the first wave of spermatogenesis, increased expression at later stages of spermatogenesis, was in agreement with the affected phase of spermatogenesis in the adult repro34/repro34 testis. We therefore concluded that the male infertility of the repro34/repro34 mouse is caused by the interruption of spermatogenesis during transition from the spermatocyte to spermatid and that the nonsense mutation of the Stx2/Epim gene is responsible for the interruption of spermatogenesis.  相似文献   
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