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排序方式: 共有213条查询结果,搜索用时 31 毫秒
141.
Aleksandar Mikić Vojislav Mihailović Branko Ćupina Svetlana Antanasović Đorđe Krstić Bojan Zlatković Vuk Đorđević Lana Zorić Ksenija Taški-Ajduković Nevena Nagl 《Euphytica》2013,193(1):1-12
Large-flowered vetch (Vicia grandiflora Scop.) is widely present in many Eurasian wild floras, where it has significance in improving grassland communities and environment-friendly uses as a cover crop and green manure. The main goal of this study was to assess the possibility of transforming large-flowered vetch into a field crop and assess the basics for its breeding. A small-plot trial was carried out in three consecutive growing seasons 2005–2008 in Novi Sad, including twelve large-flowered wild populations collected at various sites in Serbia and France from 2002 to 2004 and multiplied ex situ during subsequent years. The population MM 02/01 of Serbian origin had the highest three-year average proportion of plants surviving winter (0.96). The smallest average number of days from sowing to first flower was in the population MM 03/10 (199 days). The population MM 03/08 produced the highest forage dry matter (8.0 Mg ha?1) yield stage between full flowering and forming first pods. The highest seed yield was in the population MM 03/10 (2,084 kg ha?1). Forage dry matter yield was significantly correlated to main stem length (r = 0.932), number of fertile nodes (r = 0.710), number of internodes (r = 0.640) and number of leaves (r = 0.604). Seed yield was significantly correlated to number of pods (r = 0.930), number of seeds (r = 0.883), number of stems (r = 0.882) and number of fertile nodes (r = 0.768). Our study confirmed that large-flowered vetch may represent a stable and quality source of forage in temperate regions such as the Balkans, as well as that it may have its place in various crop rotations and farming systems. At the same time, the existing phenotypic variability offers a solid basis for further improvement of this species. 相似文献
142.
Miki Takao Chen-Goodspeed Misty Zhao Zhaoyang Lee Cheng Chi 《Journal of circadian rhythms》2013,11(1):1-2
Although out-of-lab investigation of the human circadian clock at the clock gene expression level remains difficult, a recent method using hair follicle cells might be useful. While exercise may function as an entrainment cue for circadian rhythms, it remains unclear whether exercise affects human circadian clock gene expression. Efforts to observe apparent effects of exercise on clock gene expression require that several specific conditions be met: intense exercise should be habitually performed at a relatively uncommon time of day over an extended period; and any relative phase shift thereby observed should be validated by comparison of exercise and no-exercise periods. Wake-up and meal times should be kept almost constant over the experimental period. The present study was conducted using a professional fighter who met these strict criteria as subject. Facial hair samples were collected at 4-h intervals around the clock to ascertain rhythms of clock gene expression. During a period in which nighttime training (from 20:00 to 22:00) was habitually performed, circadian clock gene expression was phase-delayed by 2 to 4 h compared with that during a no-exercise period. Maximum level and circadian amplitude of clock gene expression were not affected by the nighttime training. Our trial observations illustrate the possibility that heavy physical exercise might strongly affect the circadian phase of clock gene expression. Exercise might be therefore effective for the clinical care of circadian disorders. The results also suggest that athletes may require careful scheduling of heavy physical exercise to maintain normal circadian phase and ensure optimal athletic performance. 相似文献
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144.
Hiroki NARAHARA Eri SAKAI Masafumi KATAYAMA Yukiko OHTOMO Kanako YAMAMOTO Miki TAKEMOTO Hisashi ASO Shyuichi OHWADA Yasuaki MOHRI Katsuhiko NISHIMORI Emiko ISOGAI Takahiro YAMAGUCHI Tomokazu FUKUDA 《Animal Science Journal》2012,83(5):367-374
Genetic improvement of resistance to infectious diseases is a challenging goal in animal breeding. Infection resistance involves multiple immunological characteristics, including natural and acquired immunity. In the present study, we developed an experimental model based on genetic selection, to improve immunological phenotypes. We selectively established three mouse lines based on phagocytic activity, antibody production and the combination of these two phenotypes. We analyzed the immunological characteristics of these lines using a lipopolysaccharide (LPS), which is one of the main components of Gram‐negative bacteria. An intense immunological reaction was induced in each of the three mouse lines. Severe loss of body weight and liver damage were observed, and a high level of cytokine messenger RNA was detected in the liver tissue. The mouse line established using a combination of the two selection standards showed unique characteristics relative to the mouse lines selected on the basis of a single phenotype. Our results indicate that genetic selection and breeding is effective, even for immunological phenotypes with a relatively low heritability. Thus, it may be possible to improve resistance to infectious diseases by means of genetic selection. 相似文献
145.
Miki SAKATANI Ahmed Z. BALBOULA Kenichi YAMANAKA Masashi TAKAHASHI 《Animal Science Journal》2012,83(5):394-402
This study investigated the effect of summer heat environment on estrous cycles and blood antioxidant levels in Japanese Black cows. A total of 13 non‐lactating Japanese Black cows (summer: 9, winter: 4) were examined. Body temperature was measured rectally and intravaginally using a thermometer and data logger, respectively. Estrous behavior was monitored using a radiotelemetric pedometer that recorded walking activity. Rectal temperatures were higher during summer than winter (P < 0.001). There was an acute increase in vaginal temperature at the onset of estrus during winter but such an increase was not observed during summer. Walking activity during estrus decreased dramatically in the summer compared to the winter. Duration of estrous cycle was longer in summer (23.4 days, P < 0.05) than winter (21.5 days), and the subsequent rise in progesterone concentrations following estrus tended to be delayed in summer. The level of thiobarbituric acid reactive substances (TBARS) in peripheral blood cells was higher during summer (P < 0.05), while the levels of superoixde dismutase (SOD), glutathione peroxidase (GPx) and glutathione were lower (P < 0.05). These results indicate that high ambient temperature during summer increases both body temperature and oxidative stress, and also reduces signs of estrus in Japanese Black cows. 相似文献
146.
Kentaro Ikeda Katsuya Kuwabara Toshihiko Urushibara Pennapa Soyai Shizue Miki Satoshi Shibata 《Journal of General Plant Pathology》2012,78(5):372-375
Pink root rot of squash (Cucurbita moschata) caused by Setophoma terrestris was found in Maebashi, Gunma Prefecture, Japan in July 2007. Cucumber grafted on the squash first developed wilt and finally blight. These symptoms followed a severe pink root rot of the squash rootstock. The fungal isolates from diseased roots were identified as S. terrestris based on morphological characteristics and nucleotide sequences. One isolate induced a similar pink root rot but not entire wilting of the cucumber vine. We propose the name “pink root rot” (koshoku-negusare-byo in Japanese) of squash for the new disease. 相似文献
147.
Kentaro Ikeda Shinpei Banno Ken Watanabe Masashi Fujinaga Hideki Ogiso Hiroshi Sakai Hitoshi Tanaka Shizue Miki Satoshi Shibata Toshimasa Shiraishi Makoto Fujimura 《Journal of General Plant Pathology》2012,78(5):331-337
Chinese cabbage yellows caused by Verticillium dahliae and V. longisporum is one of the most economically important diseases in Japan. Verticillium isolates from infected Chinese cabbage in Japan were identified as V. dahliae and V. longisporum based on morphological characteristics and newly developed molecular genotyping methods using group I intron of 18S rDNA, mitochondrial-SSU rDNA and cob gene. Although the two species were equally virulent to Chinese cabbage in the greenhouse, V. longisporum was more virulent in the field compared with V. dahliae. Among the 67 Verticillium isolates from Chinese cabbage, 53 were V. longisporum and considered to be the major pathogen. The isolation frequency of V. longisporum was 98?% in Ibaraki and eastern Gunma where Chinese cabbage was cropped from autumn to winter. In contrast, the frequency was 48?% in Nagano and north to west Gunma where the plant was cropped in cool summer and highland conditions and the rests were V. dahliae. This is the first report to show the different geographical distribution of V. longisporum and V. dahliae in Chinese cabbage production area of Japan. 相似文献
148.
One-carbon metabolism (OCM) can be seen as integrated metabolic pathways centered on the metabolism of two nutritional substances, folate and methionine. Mammalian oocytes and preimplantation embryos express almost all enzymes that participate in OCM, suggesting that they can independently metabolize OCM nutrients. A deficiency or excess of OCM nutrients and their metabolites during in vitro culture affects preimplantation development of mammalian embryos. Recent in vivo studies have demonstrated that specific OCM dietary interventions during the periconceptional (mainly oocyte growth and preimplantation) period can cause epigenetic alterations in DNA of offspring and program the long-term consequences in their health in adulthood. The epigenetic processes are likely to be implicated in the effects of OCM nutrients; however, understanding their effects at the level of specific genes and their implications in assisted reproductive technology will require further investigations. 相似文献
149.
150.
Hirao H Hoshi K Kobayashi M Shimizu M Shimamura S Tanaka R Machida N Maruo K Yamane Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(5):559-562
A three-month-old male Golden Retriever had symptoms including exercise intolerance, dyspnea and syncope and was diagnosed with subvalvular aortic stenosis. Cardiac catheterization revealed a left ventricular-aortic systolic pressure gradient of 90 mm Hg. Surgical correction of the condition was achieved using cardiopulmonary bypass. The subvalvular fibrous lesion was resected through an aortotomy. The stenosis was dilated from 8.5 mm to 12.0 mm in diameter. Postoperatively the dog was asymptomatic. Seven months after surgery, the pressure gradient decreased to 44 mm Hg. However, after another three months, the dog died suddenly without any premonitory signs. Postmortem examination revealed that pathologic changes caused by increased left ventricular pressure overload were not severe. 相似文献