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81.
The objective of this study was to investigate the relationship between marbling and serum leptin concentrations. First, we compared serum leptin concentrations between Japanese Black cattle and Holstein calves, and found that the mean serum concentration was significantly higher (P < 0.05) in Japanese Black cattle (2.67 ± 0.41 ng/mL, n = 13) than in Holstein calves (1.79 ± 0.43 ng/mL, n = 5). We then examined the effects of roughage intake or vitamin A on the serum leptin concentrations in Japanese Black cattle. Although the leptin concentrations for the high roughage group were significantly higher than those for the low roughage group at 4, 7 and 20 months old, there was no significant difference in the carcass characteristics of the two groups. In addition, although there was a significant difference in the marbling score between the high vitamin A group and low vitamin A group, there was no significant difference in serum leptin concentrations between the groups. These results suggest that although serum leptin concentrations were not significantly correlated to the marbling scores they may be related to the genetic advantage for marbling in Japanese Black cattle.  相似文献   
82.
Luo  Fan  Hu  Xue-Feng  Oh  Kokyo  Yan  Li-Jun  Lu  Xin-Zhe  Zhang  Wei-Jie  Yonekura  Tetsushi  Yonemochi  Shinichi  Isobe  Yugo 《Journal of Soils and Sediments》2020,20(11):4011-4022
Purpose

We studied the profitable phytoremediation method with commercial chrysanthemum (Chrysanthemum indicum L.) in order to remediate the soils contaminated with heavy metals and generate economy income from the contaminated sites.

Materials and methods

A field experiment was carried out to remediate the contaminated soil through growing the commercial chrysanthemum plants in a farmland polluted with heavy metals of Cd and Zn due to application of creek sediments in the western suburb of Shanghai, Southeast China, since June 2013.

Results and discussion

After the consecutive 3 years of phytoremediation, Cd and Zn contents in the soil were reduced by 78.1% and 28.4%, respectively. We also found that the rice grain growing on the 3-year phytoremediated soil met the requirements of dietary safety, so did the vegetable growing on the 5-year phytoremediated soil.

Conclusions

Growing chrysanthemum plants as a method of phytoremediation can not only remove a large amount of toxic heavy metals from the contaminated soil but also be highly profitable from the sales of chrysanthemum flowers.

  相似文献   
83.
Out of 700 heifers at a local farm in Hokkaido, the Northern island of Japan, 560 (80%) were found to have benign teat tumors. All of the analyzed tumors were macroscopically of the flat-and-round type, and no other types such as rice-grain or frond epithelial type were found. The lesions were characterized by epithelial hyperplasia, acanthosis and hyperkeratosis. Unlike in typical fibropapilloma, fibroplasia of the underlying dermis was not observed. Bovine papilloma virus (BPV) capsid antigen and virus particles were found in basophilic intranuclear inclusions of the stratum granulosum of the epidermis by immunohistochemistry and electron microscopy, respectively. BPV-specific DNA was also detected in the lesions. By means of the polymerase chain reaction (PCR) and DNA sequencing of the PCR products, the viruses causing this outbreak were identified mainly as BPV-6 (64%), partly as unclassified BPVs (14%) and their co-infections (21%). Our findings suggest that this outbreak of benign teat tumors was associated with several BPV types.  相似文献   
84.
Abstract

Biochar application to soils can mitigate carbon dioxide (CO2) by increasing soil carbon (C) sink, but also causes increased CO2 released from soils through priming effects of soil organic carbon (SOC). However, priming effects of biochar application on SOC are complex, showing inconsistent results, and further complicated when applied with other substrates such as organic amendment (OA). Incubation experiments were conducted using Typic Durudand with bamboo (Phyllostanchys edulis Carrière) biochar (400°C) and OA (crotalaria) applied individually, simultaneously or with biochar applied 5 weeks prior to OA application. After 56 d of incubation, cumulative CO2 released from soils with no amendments (control), biochar only (BC), OA only (OA), simultaneous (BC+OA), and differently timed (BCP+OA) applications reached 313, 326, 1270, 1535 and 1311 mg CO2 kg?1, respectively. The OA application distinctly increased CO2 released from the soils due to its decomposition. The OA decomposition rates were comparable with OA and BC+OA, while those with BCP+OA were lower than those with other treatments during early incubation. Net CO2 (CO2-(treatment) ? CO2-control) from soils with BC, OA, BC+OA and BCP+OA yielded 13, 957, 1222 and 998 mg CO2 kg?1, respectively. Primed CO2-BC of 13 mg CO2 kg?1 was equivalent to 4.2% of priming effect relative to CO2-control. Primed CO2-BC+OA [net CO2-BC+OA ? (net CO2-BC + net CO2-OA)] and primed CO2-BCP+OA were 252 and 28 mg CO2 kg?1, equivalent to 26% and 2.9% of priming effects relative to sum of net CO2-BC + net CO2-OA, respectively. The priming effect with BC was negligible likely because of limited amounts of biochar labile C to induce co-metabolism, while BC+OA showed a modest priming effect most likely as a result of co-metabolism induced by additional mineralization of presumably SOC and/or biochar, because the OA decomposition rates were not affected by biochar application. The priming effect with BCP+OA was comparable to that with BC likely due to changes in soil properties caused by biochar application prior to OA, likely from slowed decomposition rates of OA.  相似文献   
85.
To search for an index for chemical composition related to superior taste in Japanese Black beef, we conducted panel tests and analyzed the chemical composition of seven beef brands. Thirty‐five sirloin beefs from five heifers were used in this study, sold under seven beef brands graded as more than A4 on the Japanese Meat Grade scale. The chemical composition analyses assessed both raw and roasted meat, the latter of which was roasted under the same conditions as those used for the panel test. Results of the panel test and chemical composition analyses revealed that fatty acid composition, sugar content, adenosine triphosphage (ATP)‐related compounds, amino acid composition and odor composition in the sirloin meat differed among beef brands. Furthermore, the correlations of chemical compositions between roasted and raw meat were significantly high. Sugar content and ATP‐related compounds in roasted meat were significantly correlated with the item ‘overall evaluation’ of the panel test. ATP‐related compounds, such as inosinic acid, carnosine and taurine, in roasted and raw meat were correlated significantly with the item ‘umami intensity’ of the panel test. These results suggest that the composition of these components is important for an index related to the overall evaluation of beef.  相似文献   
86.
Leptin mRNA is expressed in not only adipocytes but also mammary epithelial cells and leptin protein is present in milk. Although milk leptin is thought to influence metabolism or the immune system in neonates, there is little information about the regulation of leptin expression in mammary epithelial cells. We examined the effect of growth hormone (GH) and/or lactogenic hormone complex (DIP; dexamethasone, insulin and prolactin) on leptin mRNA expression in mammary epithelial cells. We used a bovine mammary epithelial cell (BMEC) clonal line, which was established from a 26-day pregnant Holstein heifer. We confirmed that the mRNA was expressed in BMECs and the expression was significantly reduced by GH and/or DIP, when the cells were cultured on both plastic plates and cell culture inserts at days 2 and 7 after stimulation with lactogenic hormones. GH and/or DIP significantly increased level of alpha-casein mRNA in BMECs after 7 days on the cell culture inserts, but no mRNA expression was detected at day 2. GH and DIP significantly stimulated the secretion of alpha-casein from BMEC on cell culture inserts at 3.5 and 7 days. However, neither alpha-casein mRNA expression nor secretion was observed in the BMECs cultured on plastic dishes, even in the presence of GH or/and DIP. These results indicate that GH and DIP can directly reduce leptin mRNA expression in both undifferentiated and functionally differentiated bovine mammary epithelial cell.  相似文献   
87.
Bovine foamy virus (BFV) is distributed through worldwide cattle herds. Although the biological features of BFV are not well understood, appearance of clinical manifestation by superinfection with other microorganisms is inferred. In Japan, reports of genomic characterizations and epidemiology of this virus are limited. In this study, we performed whole genomic sequencing of BFV strains Ibaraki and No.43, which were isolated in this country. Additionally, we investigated BFV in geographically distant four daily farms in Japan, to estimate the distribution of BFV and its correlation to bovine leukemia virus (BLV). BFV was distributed throughout Japan; the average positive rate was 12.7%. The nucleotide sequence identities of the isolates were 99.6% when compared with BFV strain isolated in the USA. The phylogenetic tree using env gene sequence showed strains Ibaraki, No.43 and Kagoshima were sorted in the same cluster including the USA and Chinese strains, while Hokkaido strain was in the other cluster including European strains. Although no clear correlation between BFV and BLV could be found, BFV and BLV infections were likely to increase with ages. Our data on epidemiology and characteristics of BFV will provide important information to reveal biological features of BFV.  相似文献   
88.
In order to estimate mean tree height using small-footprint airborne light detection and ranging (LiDAR) data, a digital terrain model (DTM), which is a continuous elevation model of the ground surface, is usually required. However, generating accurate DTMs in mountainous forests using only the LiDAR data is laborious and time consuming, because it requires human-assisted methods, especially in the forests with poor laser penetration rates. Based on our previous finding that a hypothetical continuous surface model passing through the predominant tree tops (hereafter, called the “top surface model” or TSM) might be nearly parallel to a DTM, we assumed that the vertical difference between the TSM and the ground return was the mean tree height. According to this assumption, we propose a new methodology that does not require a DTM to estimate mean tree height. This method completely, automatically, and directly estimates mean tree height (MTH E) from the LiDAR data without requiring a regression analysis using reference data. From the relationships between the MTH E and the observed mean tree height (MTH O) in different hinoki cypress forests, we demonstrate that this method effectively estimates the mean tree height with nearly 1-m accuracy.  相似文献   
89.
Neuraminidase is a rational target for influenza inhibition, and the search for neuraminidase inhibitors has been intensified. Mimosine, a nonprotein amino acid, was for the first time identified as a neuraminidase inhibitor with an IC(50) of 9.8 ± 0.2 μM. It was found that mimosine had slow, time-dependent competitive inhibition against the neuraminidase. Furthermore, a small library of mimosine tetrapeptides (M-A(1)-A(2)-A(3)) was synthesized by solid-phase synthesis and was assayed to evaluate their neuraminidase and tyrosinase inhibitory properties. Most of the tetrapeptides showed better activities than mimosine. Mimosine-FFY was the best compound, and it exhibited 50% neuraminidase inhibition at a low micromolar range of 1.8 ± 0.2 μM, whereas for tyrosinase inhibition, it had an IC(50) of 18.3 ± 0.5 μM. The kinetic studies showed that all of the synthesized peptides inhibited neuraminidase noncompetitively with K(i) values ranging from 1.9 -to 7.2 μM. These results suggest that mimosine could be used as a source of bioactive compounds and may have possibilities in the design of drugs as neuraminidase and tyrosinase inhibitors.  相似文献   
90.
A 5-day-old hornless goat was referred with dysuria since birth. The scrotum was absent, and a small penis-like structure was seen below the perineal raphe. On the laparotomy, the testicles were found near the inguinal ring- and attached to a uterus-like structure. On histological analysis, the uterus-like structure was blind-end. Germ cells were absent in the testis. The karyotype of this goat was 60, XX and the SRY gene was absent. The goat was homozygous for a DNA deletion responsible for the Polled Intersex Syndrome (PIS). To the authors' knowledge, this is the first report as the clinical case of the PIS-/- goat with urethral atresia.  相似文献   
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