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81.
Weng Q Shi Z Kawaguchi M Watanabe G Taya K 《The Journal of reproduction and development》2008,54(5):397-401
Characteristic daily increases in the plasma levels of luteinizing hormone (LH) are present every afternoon during lactation in golden hamsters. The objective of this study was to investigate the effect of the diurnal rhythm of increases in LH on expression of nerve growth factor (NGF), its receptors trkA and p75 and inhibin alpha-subunit in the ovarian interstitial cells of lactating golden hamsters. Both lactating and non-lactating groups of postpartum golden hamsters were used in this study. The expression of NGF, its receptors trkA and p75 and inhibin alpha-subunit were determined by immunohistochemistry. Positive staining of NGF, trkA and p75 was found in the interstitial cells of the lactating group, and no immunoreactivity for NGF, trkA or p75 was observed in the ovarian interstitial cells of the non-lactating group. In addition, immunostaining of inhibin alpha-subunit was also observed in the interstitial cells of the lactating group but not in those of the non-lactating group. Immunostaining of the inhibin/activin beta(A)- and beta(B)-subunits was observed in the granulosa cells of antral follicles, but not in the interstitial cells of the lactating and non-lactating animals. These results suggest that the diurnal rhythm increases in LH can induce expression of NGF, trkA, p75 and inhibin alpha-subunit in the ovarian interstitial cells of lactating golden hamsters and that NGF, its receptors trkA and p75 and inhibin alpha-subunit may have the capacity for autocrine or paracrine modulation of interstitial cell differentiation in golden hamsters. 相似文献
82.
Trisomboon H Tohei A Malaivijitnond S Watanabe G Taya K 《The Journal of reproduction and development》2008,54(5):375-380
To investigate the androgenic effect of Kaempferia parviflora (KP), a Thai herbal plant, adult male rats were randomized into control and KP-treatment groups. Rats were treated orally with water in the control group and with 1,000 mg/kg/day of KP in the treatment group for 45 days. Blood samples were collected on days 10, 20, 30 and 45 for measurement of the serum follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone, progesterone and corticosterone levels. The reproductive and non-reproductive organs were dissected on day 45 and weighed. Mating behavior was also observed on days 20 and 30. Body weight was measured throughout the study period. The results showed that KP induced an increase in body weight compared with the controls. There were no significant differences in the weights of either reproductive (testis, seminal vesicle plus coagulating gland, levator ani muscle plus bulbocarvernosus muscle and glans penis, except the prostate gland) or non-reproductive organs (kidney, adrenal gland and gastracnemius muscle). There were no significant differences in serum levels of either FSH or LH between the two groups. The serum testosterone and progesterone levels were insignificantly lower in the KP group during the first 30 days. The serum corticosterone levels in the KP group were lower than those in the controls throughout the study period and were significantly low on days 20 and 30. There were no significant changes in mating behavior in the rats treated with KP. Although KP affected the body weight and serum corticosterone level, it did not affect mating behavior, reproductive and non-reproductive organ weights or hormones related to the reproductive system in the adult male rats. Therefore, we conclude that the testosterone-like effect of KP did not disturb the hypothalamic-pituitary-testicular axis or male reproduction. 相似文献
83.
Norio KANSAKU Aya SOMA Satoko FURUKAWA Gen HIYAMA Hisato OKABAYASHII Daniel GUÉMENÉ Urs KÜHNLEIN David ZADWORNY 《Animal Science Journal》2008,79(2):163-170
The duck growth hormone encoding gene and its promoter region were amplified by polymerase chain reaction (PCR). A total of 5.25 kb were cloned and sequenced. Duck growth hormone (GH) consists of five exons and four introns and is structurally similar to mammalian and chicken GH gene. Although the distal region of duck GH promoter showed no similarity to chicken and turkey promoters, the proximal region of the promoter contained two putative Pit‐1 binding sequences, and showed similarity to chicken and turkey GH promoters. Genetic variation was detected at five positions of the promoter region. The results of this study indicate that the expression of duck GH is likely regulated in a similar manner to that of chicken GH via enhancer‐type cis‐acting elements and the presence of genetic variation in the duck GH gene may be applicable to marker‐assisted selection. 相似文献
84.
为了比较不同紫花苜蓿品种对病毒病的抗性,对30个紫花苜蓿品种的病毒病发病情况进行了田间调查,利用小RNA深度测序技术结合RT-PCR技术检测鉴定各紫花苜蓿品种中的病毒种类,并测定了各紫花苜蓿品种的发病率、病情指数、相对株高、相对单株干重、相对茎秆直径、相对叶面积、相对叶长和相对叶宽,综合比较各紫花苜蓿品种的抗性,并对部分指标进行系统聚类分析。结果表明:30个紫花苜蓿品种均只受到苜蓿花叶病毒(alfalfa mosaic virus, AMV)的侵染,所有紫花苜蓿品种的田间发病率均超过94%,病情指数范围为31.53~55.50;30个紫花苜蓿品种中,抗性较强的品种有1个,为射手2号,抗性一般的品种有6个,其余23个品种的抗性较差,分别占供试品种的3.33%,20.00%和76.67%;聚类分析结果表明,抗性较强的射手2号与其他紫花苜蓿品种的亲缘关系较远,与其杂交有可能产生较大的杂种优势。 相似文献
85.
C. C. Hwang M. Igase M. Sakurai T. Haraguchi K. Tani K. Itamoto T. Shimokawa M. Nakaichi Y. Nemoto S. Noguchi M. Coffey M. Okuda T. Mizuno 《Veterinary and comparative oncology》2018,16(2):229-238
Oncolytic virotherapy is a novel treatment involving replication‐competent virus in the elimination of cancer. We have previously reported the oncolytic effects of reovirus in various canine cancer cell lines. This study aims to establish the safety profile of reovirus in dogs with spontaneously occurring tumours and to determine a recommended dosing regimen. Nineteen dogs with various tumours, mostly of advanced stages, were treated with reovirus, ranging from 1.0 × 108 to 5.0 × 109 TCID50 given as intratumour injection (IT) or intravenous infusion (IV) daily for up to 5 consecutive days in 1 or multiple treatment cycles. Adverse events (AEs) were graded according to the Veterinary Cooperative Oncology Group‐ Common Terminology Criteria for Adverse Events (VCOG‐CTCAE) v1.1 guidelines. Viral shedding, neutralizing anti‐reovirus antibody (NARA) production and immunohistochemical (IHC) detection of reovirus protein in the tumours were also assessed. AE was not observed in most dogs and events were limited to Grade I or II fever, vomiting, diarrhoea and inflammation of the injected tumour. No infectious virus was shed and all dogs had elevated NARA levels post‐treatment. Although IHC results were only available in 6 dogs, 4 were detected positive for reovirus protein. In conclusion, reovirus is well‐tolerated and can be given safely to tumour‐bearing dogs according to the dosing regimen used in this study without significant concerns of viral shedding. Reovirus is also potentially effective in various types of canine tumours. 相似文献
86.
87.
高粱—苏丹草杂交种的应用可行性研究及其选育 总被引:8,自引:0,他引:8
利用生产上推广的6个粒用高粱杂交种和4个高粱杂交种为对照,与随机组配的15个高粱-苏丹草杂交种进行比较。结果表明,高粱-苏丹草杂交种做饲用生产能力上仅次于甜高粱杂交种,但在早熟优质等若干特性上优于甜高粱,有些组合还高于甜高粱杂交种的生产能力。该类型杂交种干物质及绿色体的日生产能力高于甜杂2号21.1%和41.2%,原因是杂最高。 相似文献
88.
Taro Hirose Masaki Sakurai Shingo Watari Michio Ogawa Mitsutaku Makino 《Fisheries Science》2017,83(6):879-885
Overfishing has reduced the stock of hairtail Trichiurus japonicus around the Bungo Channel, Japan. To determine whether using larger bait in the trolling line fishery could avoid catching small/undersize hairtail, we developed and trialled a new large artificial bait (a soft plastic bait, 6 inches long). A traditional lure with natural bait (type-1), a new lure of the new artificial bait hook without natural bait (type-2), and a new lure with natural bait (type-3) were tested in fishing operations around the Bungo Channel. Compared with type-1, type-2 and type-3 caught fewer undersized and immature female individuals. The number of fish caught, yield, and composition of commercial size grades per recruitment were calculated from field data for each lure and compared. The catch sizes (number of fish per recruitment) were smaller for type-2 and type-3 than for type-1, but yield per recruitment was higher for type-3 than for type-1. Compared with type-1, type-2 and type-3 caught more large individuals, which are more valuable. The newly developed artificial bait conserves hairtail stocks by targeting larger fish, which is economically beneficial for the hairtail trolling line fishery. 相似文献
89.
Sakiko Orui Sakaguchi Shigeru Shimamura Yuichi Shimizu Gen Ogawa Yuichiro Yamada Keiko Shimizu Hiroaki Kasai Hiroshi Kitazato Yoshihiro Fujiwara Katsunori Fujikura Kiyotaka Takishita 《Fisheries Science》2017,83(1):47-56
To identify the stomach contents of marine organisms, morphological observations are commonly conducted. However, the results obtained by this traditional method are frequently biased, as it is difficult to detect partially digested, soft-bodied organisms. To resolve this, recent studies have used DNA-based (DNA barcoding) analyses to examine the diet breadth of marine organisms. Here, we compared the prey richness of juvenile fishes using morphological observations and DNA-based analyses, with a focus on juvenile chum salmon Oncorhynchus keta. A higher number of prey taxa were successfully identified using DNA-based analyses than morphological observations. However, we also noticed several shortcomings of the DNA-based analyses, as reported in other diet-analysis studies that used molecular techniques. For example, the degree of digestion among prey taxa might have resulted in differential sensitivity to DNA detection. Additionally, several prey taxa could not be precisely identified, as the sequence data for some of the targeted organismal groups are unavailable in public gene databases. Remarkably, it is also possible that DNA-based analyses detected secondary prey, and therefore, the richness of prey taxa was likely overestimated. Thus, dietary analyses of juvenile fishes need to be carefully conducted, considering the respective advantages and disadvantages of DNA-based and morphological techniques. 相似文献
90.
不同早籼基因型水稻的空间诱变效应研究 总被引:16,自引:0,他引:16
本研究结果表明 ,空间搭载种子的发芽率、存苗率和结实率除迟熟品种外均低于对照 ,对秧苗的生长表现出刺激和抑制两种作用 ,生理损伤比地面γ射线处理的轻得多。空间搭载对杂种 1代处理的SP2 代单株有效分蘖的分离具有一定的稳定作用。SP2 代在株高、分蘖和抽穗期等性状上出现了较大的分离 ,突变频率和诱变效率因不同基因型材料差异较大 ,而且一些性状的突变具有一定的方向性。在空间处理的SP2 代就出现较多综合性状优良的突变体 ,可望直接育成新品种 相似文献