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41.
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   
42.
Chromogranin A (CGA) is a member of a family of highly acidic proteins co-stored and co-released with catecholamines in the adrenal medullary cells as well as in other neurons and paraneurons. The nucleotide sequence encoding equine CGA was determined using RT-PCR and rapid amplification of complementary DNA (cDNA) ends (RACE) techniques. A total 1,828 bp of the nucleotide sequence reveals that equine CGA is a 448-residue protein preceded by an 18-residue signal peptide. Comparison of the amino acid sequence of equine CGA with those of human, porcine, bovine, mouse, rat and frog CGA showed high conservation at the NH2-terminal 1-77 amino acids regions (94.8%, 93.5%, 92.2%, 81.8%, 83.1% and 66.2%, respectively) and COOH-terminal 314-430 amino acids regions (90.6%, 81.4%, 90.6%, 80.5%, 83.3% and 39.0%, respectively), as well as a potential dibasic cleavage site, whereas the middle portion showed marked sequence variation (52.5%, 49.1%, 38.9%, 26.6%, 27.9% and 6.2%, respectively). Northern blot analysis and RT-PCR elucidated the tissue distribution of equine CGA mRNA. Its expression was confirmed not only in the adrenal medullary cells but also in other organs (cerebrum, cerebellum, pituitary gland, spinal cord, liver, thyroid gland, striated muscle, lung, spleen, kidney, parotid gland and sublingual gland). Further, in adrenal chromaffin cells and pituitary cells of the anterior-intermediate lobe, the expression was confirmed by in situ hybridization with anti-sense CGA cRNA probe.  相似文献   
43.
ABSTRACT The presence of mulberry dwarf (MD) phytoplasmas in organs of the inoculative vector insects Hishimonoides sellatiformis and Hishimonus sellatus was determined by means of electron microscopy (EM) and polymerase chain reaction (PCR) assays. Many MD phytoplasmas were detected in genital organs as well as in the intestines, salivary glands, brains, fat bodies, and thoracic ganglia of Hishimonoides sellatiformis, but only in the intestine and salivary glands of Hishimonus sellatus. Many phytoplasmas with characteristic morphology were observed via EM in ovaries, seminal receptacles, and testes, and they were further identified by PCR assays with group I-specific primers. In addition, the organisms were detected by direct or nested PCR assays in eggs (head pigmentation stage of embryos) laid on mulberry shoots by inoculative leafhoppers and in the newly hatched nymphs from these eggs. These findings indicate that transovarial transmission of MD phytoplasmas occurs in Hishimonoides sellatiformis.  相似文献   
44.
Watanabe K  Nagahama K  Sato M 《Phytopathology》1998,88(11):1205-1209
ABSTRACT Previous work suggested that the efe gene encoding the ethylene-forming enzyme was present in the plasmids of three pathovars of Pseudomonas syringae including glycinea, phaseolicola (kudzu strains), and cannabina. However, no direct evidence to support this assumption had been presented. In the current study, we isolated the conjugative plasmid harboring the efe gene (ethylene plasmid) designated pETH2 from P. syringae pv. glycinea MAFF301683. pETH2 was detected by Southern blot hybridization using the efe probe, marked with the transposon mini-Tn5-Km1, and transferred into P. syringae Ni27(n), which does not produce ethylene. The transconjugant Ni27(n) (pETH2) produced ethylene at a level similar to pv. glycinea MAFF301683. In addition, the plasmid designated pCOR2, which encodes coronatine biosynthesis genes, was detected in the same strain. Although the molecular size of the plasmid pCOR2 was not easily distinguishable from pETH2, pCOR2 transferred independently into Ni27(n) and the transconjugants produced coronatine. These findings suggested that the efe gene has been horizontally dispersed among pathovars of P. syringae by plasmid-mediated conjugation in nature.  相似文献   
45.
Cytopathogenic and non-cytopathogenic bovine viral diarrhea viruses (BVDVs) were isolated from cattle with mucosal disease or persistent infection in Japan. These isolates were compared for antigenic properties by cross-neutralization tests with Japanese reference strains of BVDV belonging to classical type 1. Significantly low cross-reactivity to reference strains was noted, indicating the viruses to possibly represent a new serotype in Japan. Thus, to determine the genotype of the isolates, nucleotide sequences of the 5′ untranslated region were determined and compared with those of previously reported BVDV 1 and 2. The isolates were clearly shown to belong to BVDV 2, not to BVDV 1.  相似文献   
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ABSTRACT:   The changes in physical habitats and responses of fish, e.g. the Kirikuchi charr Salvelinus leucomaenis japonicus , were examined by placing instream structures in a stream on the upper drainage of the Totsu River system of the Kii Peninsula, Japan, over a two-year period. Instream structures created pools below the structures, and these pools have maintained their functions as fish habitats over two years. In two treatment sections, sections A and B (some red-spotted masu salmon were removed in advance in section B), mean water depth increased soon after placing the structures, but decreased over two years. Mean water velocity slowed after placing the structures in both sections. Total fish abundance has been relatively high at the two treatment sections compared with a control section after placing the structures. Age 1 Kirikuchi charr, however, increased only in section B. These results indicate that instream structures can serve as habitat enhancement for fish, including Kirikuchi charr, in the study area if other appropriate habitat factors for respective species are taken into consideration.  相似文献   
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The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species.  相似文献   
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