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571.
The aim of the study was to assess the relationship between acute and subacute metabolic and endocrine effects after intravenous administration of the 2-adrenergic agonist clenbuterol in a growth-promoting dose to female pigs. Acute metabolic and endocrine effects were assessed by measuring the blood glucose, serum insulin and nonesterified fatty acid (NEFA) concentrations during 300 min after a single administration of clenbuterol. Significantly higher serum insulin and NEFA concentrations (19.90±2.50 U/ml, p<0.01, and 0.69±0.04 mmol/L, p<0.001, respectively) were measured 30 min after the preprandial administration of clenbuterol in female pigs. Over the same period, the levels of blood glucose (4.42±0.30 mmol/L) showed no difference from those of control pigs. The postprandial serum NEFA concentration decreased moderately during 210 min after feeding. Postprandial blood glucose and insulin concentrations increased and reached maximal levels 120 min after clenbuterol administration (10.91±0.60 mmol/L and 85.22±7.24 U/ml, respectively), and returned to basal levels at 300 min (4.20±0.21 mmol/L and 7.75±1.60 U/ml, respectively) after the administration of clenbuterol. Subacute metabolic and endocrine effects were assessed by measuring the blood glucose, serum insulin and NEFA concentrations for 21 days after the repeated doses of clenbuterol. In addition, the influence of clenbuterol administration on the endocrine regulation of the onset of the next expected oestrus in female pigs was assessed by measuring their serum 17-oestradiol and progesterone concentrations. Blood glucose, serum insulin and NEFA concentrations after the last administration of clenbuterol did not differ significantly from those in control animals. The onset of the next expected oestrus occurred regularly without any significant difference in serum 17-oestradiol or progesterone concentrations between the treated (9.83±2.60 pg/ml and 0.15±0.03 ng/ml) and control pigs (8.52±2.70 pg/ml and 0.25±0.06 ng/ml). The study results suggest the duration of intravenous administration of clenbuterol in a growth-promoting dose necessary to influence the metabolic and endocrine activities in female pigs. 相似文献
572.
Effect of cold shock and hormone on growth and male morphotypes of freshwater prawn,Macrobrachium rosenbergii (de Man) 下载免费PDF全文
Mst Rubia Banu Annie Christianus Natrah Fatin Mohd Ikhsan Amy Halimah Rajaee 《Aquaculture Research》2016,47(12):3740-3746
A study was carried out to determine the effects of cold shock and 17α‐methyl testosterone hormone on growth in male morphotypes of giant freshwater prawn Macrobrachium rosenbergii. Juvenile males were exposed at 18 ± 0.25°C for 24 h with normal feed and cultured at 27 ± 0.7°C for 70 days as well as administrated feed with hormone separately at 400 mg kg?1 feed for the first 30 days of culture period (70 days). The growth (Mean ± SD) of male juveniles at harvest was closely homogenous in the cold shock (CLS) treated group; while it was heterogeneous in hormone‐treated (MH) and control (CO) groups. Although total body weight of blue claw (BC) males was not significantly different in the controls and the treatments, the 2nd pereiopods (claw) weight and length of the BC was significantly lower in CLS (0.52 ± 0.05 g, 10.02 ± 0.65 cm) than that in the CO (0.71 ± 0.16 g, 12.53 ± 0.57 cm) and MH (0.75 ± 0.08 g, 12.85 ± 1.18 cm) treatments. Survival of prawns was similar in treatments. The morphotypes of male prawn were significantly different with 59% of BC males with small‐sized claws in CLS and, 45% and 30% of BC males with large‐sized claws in MH and CO respectively. Cold shock adversely affected male morphotypes of the prawn so that numbers of BC males with small‐sized claw was the highest in CLS tank. However, the CLS treatment resulted in more uniform marketable prawns and suggested a high production of BC males in an all‐male culture system. 相似文献
573.
在长期的进化过程中,生物逐步形成了应对各种DNA损伤的修复机制,以保护基因组的完整性,减轻或消除DNA损伤的影响。本研究通过同源搜索找到了与DNA损伤修复相关水稻同源基因,在水稻插入突变体库中搜索出插入突变系,并成功引进了其中的26份T1代突变材料。通过对插入位点的分子鉴定和进一步培育,获得了14份涉及8个水稻DNA损伤修复同源基因的T3代纯合插入突变系,并对其进行了初步的遗传分析和表型考察。这些纯合突变系涉及的水稻基因可能在DNA错配修复(Os02g0592300、Os09g0407600、Os10g0509000)和碱基切除修复(Os02g0465112、Os06g0643600、Os05g0567500、Os04g0673400、Os09g0420300)中发挥重要作用。与亲本相比,除1份材料外,其他纯合突变体系及其野生型姐妹系的结实率均有显著降低;某些纯合突变系的千粒重与亲本相比有显著下降。这些水稻DNA损伤修复基因突变系的育成为开展水稻DNA修复的遗传学和分子生物学研究以及培育抗逆水稻提供了珍贵的实验材料。 相似文献
574.
Hossam EL-SHEIKH ALI Go KITAHARA Youji TAMURA Ikuo KOBAYASHI Koichiro HEMMI Shidow TORISU Hiroshi SAMESHIMA Yoichiro HORII Samy ZAABEL Shunichi KAMIMURA 《The Journal of reproduction and development》2013,59(1):59-65
The aim of the present study was to describe the temperature of the different portions
of the female genital tract and their relation to rectal temperature and to investigate
the effect of steroid hormones profiles on these variables over the estrous cycle in
cattle. Four nonpregnant Japanese Black cows were investigated daily over two successive
estrous cycles using a digital thermometer with a long probe and rounded-end sensor to
record the temperature of the rectum (RT), vagina (VT), cervix (CT), uterine body (UBT)
and uterine horns (UHT). Blood samples were collected immediately before temperature
recording to assay peripheral levels of progesterone (P4) and estradiol-17β
(E2). Moreover, transrectal ultrasonography was carried out after temperature
recording to monitor the ovulatory follicle and track ovulation. During the experiment,
the ambient temperature and relative humidity were recorded for further calculation of the
temperature humidity index (THI). The temperature within the genital tracts in these cows
progressively increased towards the uterine horns from the vagina. The VT, CT, UBT and
UHTs were significantly higher in association with peripheral P4 concentrations
greater than 4 ng/ml (mid-luteal phase) when compared with lower peripheral P4
concentrations. The VT was more significantly (P<0.01) correlated to the CT, UBT and
UHTs than RT. In conclusion, a temperature gradient was present among the vagina, cervix
and uterus over the estrous cycle, and changes in peripheral P4 concentrations
were associated with the thermal variations within these portions. The VT could be more
beneficial than RT in monitoring temperature of deeper portions of the female genital
tract in bovine. 相似文献
575.
为了保障甘谷辣椒产业健康发展,选育出适宜当地栽培的辣椒新品种,天水市农业科学研究所对甘谷线辣椒生产田发现的制干优良单株采用网室选育和日光温室加代选育相结合的系谱选育方法,育成了制干线辣椒新品种天椒17号。在2015 — 2016年进行的甘肃省线辣椒新品种多点区域试验中,天椒17号2 a 12点(次)干椒平均折合产量为5 011.80 kg/hm2,较对照品种甘谷线椒增产14.71%。天椒17号为早中熟制干线辣椒,定植到红果成熟历时100 d左右。株高84.5 cm,生长势较强。果线型,果顶尖,果面皱,果长20.40 cm,果粗1.20 cm,果肉厚0.12 cm,单果重7.4 g,单株结果51个左右,青熟果深绿色,红熟果深红色,辣味强。椒果辣椒素含量为0.091 g/kg,二氢辣椒素含量为0.063 g/kg,可溶性固形物含量为148.300 g/kg,抗坏血酸含量为744 mg/kg,斯科维尔指数(SHU)为2 650,辣度为18度。中抗烟草花叶病毒病、疫病,高抗黄瓜花叶病毒病。适宜在甘肃省河西、陇中、陇东南地区及气候条件相近地区栽培。 相似文献
576.
利用已克隆得到的半滑舌鳎P450c17-I和P450c17-Ⅱ基因cDNA全长序列,通过半定量RT-PCR技术,结合雄鱼性腺发育期、各发育期血清中睾酮(T)含量,研究了这两个基因在雄性半滑舌鳎各组织内的空间表达及在雄鱼繁殖周期中的季节性表达。结果表明,半滑舌鳎P450c17-I组织分布具有广泛性,在精巢、胃、肠、心、脾和脑内都有表达,而P450c17-II组织分布具有特异性,仅在精巢和头肾内有表达。在精巢不同发育期内,P450c17-I表达与性腺发育呈正相关,而P450c17-II表达模式则相反。推测这可能是由于在整个繁殖期,P450c17-I基因在转录水平或转录后调控半滑舌鳎性类固醇激素的生成,而P450c17-II主要可能与孕激素诱导排精及精原细胞DNA复制有关。 相似文献
577.
本文讨论了17—4PHMo(OCr17Ni4Cu4Mo2Nb)钢在含1.8%H_2SO_4和4.5%NaCl的溶液中电化学腐蚀行为。试验表明:经正常热处理的试样,在含Cl~-和H~+的溶液中能生成稳定的钝化膜,这种钝化膜只有当金属阳极电位高于20毫伏时才能被击穿。同时,由于Epp值相对较正,即使钝化膜被击穿而产生局部的点蚀,也能重新钝化,恢复完整的钝化膜。本文还讨论了钢热处理后的显微组织,也讨论了热处理工艺与电化学性能之间的关系,从而阐明该钢在较高NaCl含量的酸性溶液中不易产生点腐蚀破坏。 相似文献
578.
579.
在GIS软件的支持下,利用2005—2014年MOD17A3H与MCD12Q1数据集,结合河北省2005—2012年的142个气象站点资料,利用一元线性回归法分析了河北省10年间NPP的时空演变特征,利用相关系数法分析了NPP与气候因子的相关关系。结果表明:河北省年NPP主要集中在200~400 g/(m2·a),其中NPP高值区分布在燕山北部区域和太行山东侧一带。2005—2014年河北省年NPP均值与最大值均在波动中微弱上升,年NPP均值在2012年最大为337.63 g/(m2·a)。2005—2014年NPP增长率大于10%的地区分布在冀西北区域和东南边界,其面积占比为43.03%。河北省5种植被覆盖类型按NPP年均值从大到小排列依次为:阔叶林、灌丛、草地、针叶林、农用地。河北省NPP与气温主要呈负相关,与降水主要呈正相关。 相似文献
580.
Kiyoshi Soyano Toshihiko Saito Masaki Nagae Kohei Yamauchi 《Fish physiology and biochemistry》1993,11(1-6):265-272
Blood and ovarian samples were collected at intervals of 4h prior to spawning time from medaka (Oryzias latipes) that were maturationally synchronized with artificial photoperiod (14h light: 10h dark). Plasma estradiol-17β (E2) levels increased rapidly from 16h before spawning and peaked at 8h before spawning. Follicle-enclosed oocytes (ovarian follicles) at different stages of development were isolated from the ovaries and used to study the in vitro effects of thyroid hormone (triiodothyronine; T3) on pregnant mare serum gonadotropin (GTH)-induced E2 production. GTH at a concentration of 100 IU/ml stimulated E2 production by ovarian follicles collected between 32 and 16h before spawning. At 32h before spawning, T3 (5 ng/ml) administered along with GTH (100 IU/ml) resulted in a 3.5 fold increase in E2 production, compared with GTH administered alone. These results suggest that T3 can act on ovarian follicles directly to modulate GTH-stimulated E2 production in the medaka. 相似文献