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21.
Eleven late-pregnant Jersey cows were assigned to two groups; a group (PO-RBVD group) consisting of five cows treated with an oral administration of 10 million I.U. of an encapsulated form of vitamin D3 ("rumen-bypass" VD3; RBVD3) and another group (IMVD group) consisting of the other six treated with an intramuscular injection of 10 million I.U. of vitamin D3 (VD3). The cows received the RBVD3 or VD3 administration at 7 days before the expected parturition. The changes in the plasma concentrations of vitamin D metabolites, ionized Ca (Ca++) and inorganic phosphorus (iP) were evaluated. Of the vitamin D metabolites, the plasma 25-hydroxyvitamin D concentrations in PO-RBVD group increased significantly after the RBVD3 administration and remained in high levels that were significantly higher than those in IMVD group. This suggested that RBVD3 was absorbed rapidly and excellently from the post-ruminal digestive tract without the degradation by ruminal microorganisms. The plasma Ca++ and iP concentrations in PO-RBVD group tended to be higher after the administration and around parturition than those in IMVD group. From these observations, it was suggested the oral RBVD3 administration had more potent ability to prevent parturient paresis compared with the VD3 injection used widely in Japan.  相似文献   
22.
Substance P-immunoreactive neurons projecting from the midbrain to the spinal cord of the chicken were examined by the use of the retrograde tract-tracing method combined with immunohistochemical techniques. Many small neurons were densely clustered in the rostral midline area of the midbrain (RMA), and showed substance P-immunoreactivity. These substance P-immunoreactive neurons sent axons to the intermediomedial cell column (avian autonomic preganglion) and its vicinity in the lumbar spinal segments. On the basis of the strong neuroanatomical analogy in the cytoarchitectural features, immunoreactivity, and fiber connections, the RMA was assumed to be the avian homologue of the anteromedian nucleus in the mammalian midbrain.  相似文献   
23.
The objectives of this study were to evaluate the environmental impacts of a beef cow–calf system using a life cycle assessment (LCA) method and to investigate the effects of scenarios to reduce environmental impacts on the LCA results. The functional unit was defined as one marketed beef calf, and the processes associated with the cow–calf life cycle, such as feed production, feed transport, animal management, the biological activity of the animal and the treatment of cattle waste were included in the system boundary. The present results showed that the total contributions of one beef calf throughout its life cycle to global warming, acidification, eutrophication and energy consumption were 4550 kg of CO2 equivalents, 40.1 kg of SO2 equivalents, 7.0 kg of phosphate (PO4) equivalents and 16.1 GJ, respectively. The contribution of each process to the total environmental impact in each environmental impact category showed a similar tendency to the contribution of each process in each environmental category reported in the case of the beef fattening system as a whole. The results from this analysis showed that shortening calving intervals by 1 month reduced environmental impacts by 5.7–5.8% in all the environmental impact categories examined in the current study, and increasing the number of calves per cow also reduced environmental impacts in all the categories, although the effects were smaller.  相似文献   
24.
In epidemiological surveys on Chrysanthemum chlorotic mottle viroid (CChMVd) in various chrysanthemums cultivated in Akita Prefecture, Japan, in 2002–2005, approximately 20% of cultivars harbored CChMVd, including more symptomatic types than nonsymptomatic. Large-flowered cultivars were less frequently infected than small-flowered and spray types. The number of CChMVd-infected chrysanthemums is increasing, and the disease is found throughout major chrysanthemum-producing districts. Chrysanthemums infected only with CChMVd, in general, had no noticeable symptoms of disease. Most of those dually infected with known viruses and/or viroid also had no symptoms characteristic of chlorotic mottle disease. The lack of noticeable symptoms in major Japanese cultivars may have resulted in the unnoticed spread of the viroid.  相似文献   
25.
六月龄去势公猪表现昏睡、食欲不振、站立困难。尸检发现脾脏边缘呈多重出血灶。从脾脏、肾脏、肌肉和肝脏中分离出革兰氏阳性杆菌,对分离株(TO16177)的16S rDNA基因序列比较分析发现,其可能与未发表过的隐秘杆菌属HJ57-14E菌株(登记号:gi18873551)(比较675bp个碱基,相似性达99.7%)为同一个属。脾脏组织切片的组织学检查发现呈广泛性坏死和炎症,其中革兰氏阳性杆菌显而易见。肝脏中可见多病灶的坏死斑。免疫组织化学检测发现,分离株与抗化脓性隐秘杆菌属(Arcanobacterium pyogenes)和内氏放线菌(Actinomyces naeslundii)的多克隆抗体具有交叉反应,且与后者的交叉反应更强烈。相似的反应也见于扁桃体的化脓灶中分离株,偶尔也见于脾脏和淋巴结中的分离株。本研究结果表明,这种未公开发布的隐秘杆菌属的细菌会引起生长肥育猪多器官功能衰竭,而后继发急性出血性坏死性脾炎。  相似文献   
26.
In 1999, a disease of chrysanthemum [Dendranthema grandiflorum (Ramat.) Kitamura], characterized by virescence of flowers, occurred in Okinawa Prefecture. The causal agent was identified as “Candidatus Phytoplasma aurantifolia” based on 16S rDNA sequencing. The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession number AB247462.  相似文献   
27.
Flagellin in Pseudomonas syringae is a potent elicitor of defense responses including hypersensitive cell death in dicot plants. The oligopeptides flg22 consisting of 22 conserved amino acids near the N-terminus of flagellins is reported to induce plant defense responses. Because glycosylation of the central domain of flagellin affects its elicitor activity, we investigated whether any peptide sequence in addition to flg22 is required for flagellin-induced hypersensitive reaction. A study of recombinant flagellin polypeptides indicated that the N-terminal domain including the conserved flg22 is required for flagellin-induced hypersensitive cell death in Arabidopsis thaliana.  相似文献   
28.
The effectiveness of Denapon and Ethrel as a thinning chemical for ‘Muscat of Alexandria’ grape was examined from 1980 to 1982 with various timings and concentrations of application. Ethrel applied at 50 mg l?1 by cluster-dipping or shoot-spraying at full bloom, or 6 days after full bloom, resulted in over-thinning and chemical injury, and no thinning effect was found when Ethrel was applied at 10 or 5 mg l?1 on the same dates. The only treatment which exhibited a desirable thinning effect was shoot-spraying at 50 mg l?1 12 days after full bloom, but this markedly inhibited berry growth. Denapon applied at 1667 mg l?1 by shoot-spraying at full bloom, or 6 days after full bloom, reduced the number of berries per cluster almost adequately and consistently without any unfavorable side effects. This chemical applied at 834 mg l?1 was nearly as effective as when applied at 1667 mg l?1, but the effectiveness of the former was less consistent than that of the latter. From these results, Denapon is thought to be a promising thinning chemical for ‘Muscat of Alexandria’.  相似文献   
29.
Wood Science and Technology - Tension wood, when kiln-dried, is likely to deform hugely, which is probably caused by a gelatinous layer of the gelatinous fiber. To elucidate the mechanism behind...  相似文献   
30.
In the present study, in continuation of our previous experiment in order to investigate the mode of action (MOA) of ethyl tertiary-butyl ether (ETBE) hepatotumorigenicity in rats, we aimed to examine alterations in cell proliferation, that are induced by short-term administration of ETBE. F344 rats were administered ETBE at doses of 0, and 1,000 mg/kg body weight twice a day by gavage for 3, 10, 17 and 28 days. It was found that the previously observed significant increase of P450 total content and hydroxyl radical levels after 7 days of ETBE administration, and 8-OHdG formation at day 14, accompanied by accumulation of CYP2B1/2B2, CYP3A1/3A2, CYP2C6, CYP2E1 and CYP1A1 and downregulation of DNA oxoguanine glycosylase 1, was preceded by induction of cell proliferation at day 3. Furthermore, we observed an increase in regenerative cell proliferation as a result of ETBE treatment at day 28, followed by induction of cell cycle arrest and apoptosis by day 14. These results indicated that short-term administration of ETBE led to a significant early increase in cell proliferation activity associated with induction of oxidative stress, and to a regenerative cell proliferation as an adaptive response, which could contribute to the hepatotumorigenicity of ETBE in rats.  相似文献   
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