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Tetsuka M Asada M Mogoe T Fukui Y Ishikawa H Ohsumi S 《The Journal of reproduction and development》2004,50(4):381-389
This study describes the morphological and morphometrical changes associated with prepubertal ovarian development in the Antarctic minke whale (Balaenoptera bonaerensis). Ovaries were harvested from 94 immature minke whales caught in the Antarctic Ocean during the summer feeding season (December-March). Notable differences in ovarian size and morphology were found among animals. Up to 10 folds difference in ovarian weight was found among prepubertal whales of similar body size. During the prepubertal period, ovaries grew slowly and approximately doubled their weight. The morphologies of right and left ovaries were almost identical while the growth of the ovary appears to occur preferentially on the right side. The most striking morphological feature was numerous small antral follicles less than 5 mm in diameter found in ovaries of younger immature whales. The occurrence of these ovaries was highest in whales less than 6 m long and gradually decreased as body length increased. In larger whales, the occurrence of ovaries with a smaller number of follicles up to 10 mm and thick tunica albuginea increased. Thus, the ovary of the Antarctic minke whale experiences bursts of small follicular development during the early prepubertal period before becoming a more developed ovary with fewer but larger follicles, and thick tunica albuginea. 相似文献
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IW Tenaya K Heel PA Stumbles GE Wilcox 《Veterinary immunology and immunopathology》2012,149(3-4):167-176
Jembrana disease virus (JDV) is an unusual bovine lentivirus that causes an acute and sometimes fatal disease after a short incubation period in Bali cattle (Bos javanicus). The pathological changes occur primarily in lymphoid tissues, which feature proliferating lymphoblastoid-like cells predominantly throughout parafollicular (T-cell) areas, and atrophy of follicles (B-cell) areas. Five Bali cattle were experimentally infected with JDV and all developed typical clinical signs of Jembrana disease characterised by a transient febrile response, enlargement of superficial lymph nodes and a significant leukopenia. Flow cytometric analysis of PBMC during the acute (febrile) disease phase showed that the reduced number of lymphocytes was due to a significant decrease in both the proportion and absolute numbers of CD4(+) T cells, but not CD8(+) T-cells or CD21(+) B-cells. At the end of the febrile phase, total numbers of both CD8(+) T-cells and CD21(+) B-cells increased significantly, while CD4(+) T-cell numbers remained below normal values, resulting in a significantly reduced CD4(+):CD8(+) ratio. We speculate that the persistent depletion of CD4(+) T cells following JDV infection, through lack of CD4(+) T cell help to B cells, may explain the lack of production of JDV-specific antibodies for several weeks after recovery despite an increase in CD21(+) B cell numbers. Further, our previous data showing that IgG(+) plasma cells are targets for JDV infection, correlated with our current data demonstrating an increase in CD8(+) T cell numbers, supports the suggestion that anti-viral cytotoxic T cell or other cell-mediated immune responses may be critical in the recovery process, although this remains to be formally demonstrated for JDV. 相似文献
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Sasaki Y Yamamoto K Kojima A Tetsuka Y Norimatsu M Tamura Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(12):1275-1281
Clostridium chauvoei causes blackleg, which is difficult to distinguish from the causative clostridia of malignant edema. Therefore, a single-step PCR system was developed for specific detection of C. chauvoei DNA using primers derived from the 16S-23S rDNA spacer region and partial 23S rDNA sequences. The specificity of the single-step PCR system was demonstrated by testing 37 strains of clostridia and 3 strains of other genera. A 509 bp PCR product, which is a C. choauvoei-specific PCR product, could be amplified from all of the C. chauvoei strains tested, but not from the other strains. Moreover, this single-step PCR system specifically detected C. chauvoei DNA in samples of muscle from mice 24 hr after inoculation with 100 spores of C. chauvoei, and in clinical materials from a cow affected with blackleg. These results suggest that our single-step PCR system may be useful for direct detection of C. chauvoei in culture and in clinical materials from animals affected with blackleg. 相似文献
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Rodomiro Ortiz Richard Trethowan Guillermo Ortiz Ferrara Masa Iwanaga John H. Dodds Jonathan H. Crouch Jose Crossa Hans-Joachim Braun 《Euphytica》2007,157(3):365-384
The main elements of the international wheat improvement program of the Centro Internacional de Mejoramiento de Maíz y Trigo
(CIMMYT), also known as the International Maize and Wheat Improvement Center, have been shuttle breeding at two contrasting
locations in Mexico, wide adaptation, durable rust and Septoria resistances, international multisite testing, and the appropriate
use of genetic variation to enhance yield gains of subsequently produced lines. Such an approach yielded successes known collectively
as the Green Revolution. However, at the beginning of the 21st century, this “cultivar assembly line” approach needs fine
tuning to address crop needs under increasingly adopted resource conserving practices, as well as those related to nutritional
requirements of the end-users. International wheat improvement will therefore focus on the targeting of traits in respective
mega-environments, and the use of participatory methods, especially in marginal environments. The main features of this wheat
improvement strategy include the introduction of new and novel sources of genetic variation through wild species, landraces,
and, potentially, the use of transgenes for intractable traits. This variation will be combined using international shuttle
breeding, and increased breeding efficiency will be achieved through marker-aided methods, more targeted use of crop physiology,
plant genetics, biostatistics, and bioinformatics. Likewise, CIMMYT will increase its focus on the needs of end-users by emphasizing
regional efforts in participatory research and client-oriented plant breeding. 相似文献
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Shigenori Kumazawa Masa Taniguchi Yasuyuki Suzuki Masayo Shimura Mi-Sun Kwon Tsutomu Nakayama 《Journal of agricultural and food chemistry》2002,50(2):373-377
We extracted polyphenols from carob (Ceratonia siliqua L.) pods, and evaluated the in vitro antioxidant activity of the crude polyphenol fraction (CPP). The total polyphenol content in CPP determined by the Folin-Ciocalteu method was 19.2%. The condensed tannin content determined by the vanillin and proanthocyanidin assay systems was 4.37% and 1.36%, respectively. beta-Carotene bleaching, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, inhibition of lipid peroxidation by the erythrocyte ghost, and microsomal assay systems were used to evaluate the antioxidant activity. CPP showed a stronger inhibitory effect against the discoloration of beta-carotene than other polyphenol compounds such as catechins and procyanidins. CPP had weaker antioxidant activity in the DPPH free radical scavenging, the erythrocyte ghost, and microsomal systems than authentic polyphenol compounds at the same concentrations. The activity adjusted by the polyphenol concentration was, however, comparable to that of authentic polyphenol compounds. Considering most carob pods are discarded and not effectively utilized at present, these results suggested that carob pods could be utilized as a functional food or food ingredient. 相似文献
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S. Kanetani T. Kikuchi M. Akiba K. Nakamura H. Ikegame K. Tetsuka 《Forest Pathology》2011,41(5):387-391
We examined the effectiveness of a new Bursaphelenchus xylophilus detection kit, based on loop‐mediated isothermal amplification (LAMP), in old discs taken from the stem base of B. xylophilus‐infested dead trees of Pinus armandii var. amamiana (PAAm) occurring in their natural habitats. LAMP products, representing a past B. xylophilus infection, were detected in two consecutive trials from 16 of 20 discs collected from PAAm trees that died between 2003 and 2006. Bursaphelenchus xylophilus were more frequently detected using LAMP in wood samples taken from sapwood than from heartwood. No significant differences in the detection of B. xylophilus using LAMP were observed in relation to the disc collection time (from 3 to 6 years before the analysis). Bursaphelenchus xylophilus were not detected using LAMP in four discs, although a B. xylophilus infection had been confirmed for the original PAAm trees at the time they were found dead. This may have resulted from the small amount of wood chips needed for the LAMP test or the reduced number and uneven distribution of the nematode in the old dead trees. The results indicate that the new B. xylophilus detection kit will be a very efficient tool for conducting retrospective analysis of PAAm mortality factors. 相似文献
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Gossypol, a polyphenolic aldehyde found in cottonseed, has been shown to perturb steroidogenesis in granulosa and luteal cells of rats, pigs and cattle. However, little is known about the direct effect of gossypol on theca cell functions in any species. The present study was conducted to investigate the effect of gossypol on the steroidogenesis and the expression of genes involved in it in cultured bovine theca cells. Theca cells were isolated from healthy preovulatory follicles and were cultured in the presence of luteinizing hormone (LH) for up to 7 days. During the culture period, main steroid products of the theca cells shifted from androstenedione (A4) at day 1 to progesterone (P4) from day 2 onward. At days 1 and 7, theca cells were treated with gossypol (0‐25 μg/mL) for 24 h. Gossypol inhibited LH‐stimulated theca cell A4 and P4 production in a dose‐dependent manner at both occasions. The viability of theca cells was not affected by gossypol at any doses used. Gossypol down‐regulated expressions of steroidogenic enzymes CYP11A1, HSD3B1 and CYP17A1, but not that of LHR. These results indicate that gossypol inhibits thecal steroidogenesis through down‐regulating gene expressions of steroidogenic enzymes but without affecting cell viability in cattle. 相似文献