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981.
【目的】为明确诱导管侧沟茧蜂Microplitis tuberculifer 滞育的主要因子,在田间和室内研究了不同温度和光周期下管侧沟茧蜂的滞育率和滞育茧的最佳冷藏温度。【方法】田间实验分别从8月31日到9月25日每隔5 d在室外罩笼内释放管侧沟茧蜂寄生的粘虫幼虫,待寄生蜂结茧后统计子代蜂的滞育率。室内实验共设5个不同温度(16℃, 18℃, 20℃, 22℃和24℃)和7个不同光周期(6L:18D, 8L:16D, 10L:14D, 12L:12D, 14L:10D, 16L:8D和18L:6D),分别统计寄生蜂在各个处理条件下的滞育率。【结果】在河北中部地区秋季自然条件下,8月底当日平均气温为24.4℃,日平均光照时间为12 h 51 min 时,少数蛹(5.08%)开始进入滞育;9月25日,当日平均气温为17.2℃,日平均光照时间为11 h 36 min以下时,几乎所有蛹个体进入滞育,滞育率达到99.70%。在室内人工控制条件下,当温度为22℃以上,无论光周期如何变化,管侧沟茧蜂不能进入滞育,所结茧全部为非滞育茧。温度为22℃以下存在光周期反应,在温度16℃, 18℃和20℃,光周期10L:14D时形成滞育茧数量最多,滞育率分别为100%, 89.75% 和 29.58%。可见温度和光周期二者共同影响管侧沟茧蜂的滞育。滞育茧在0℃左右条件下冷藏 240 d 和5℃左右环境条件下冷藏180 d, 成虫的羽化率和寄生能力与发育茧差异不显著(P>0.05);0℃条件下冷藏300 d,滞育茧仍有79%可以正常羽化。【结论】该寄生蜂在秋季进入滞育主要是低温条件和短光照反应相互作用的结果,滞育茧在0℃和5℃温度下至少可以保存240 d。这些结果对管侧沟茧蜂的大规模繁殖和滞育茧的保存具有重要参考价值。 相似文献
982.
983.
The reproduction of female red pandas under three different husbandry conditions (monogamy, polygamy, and polyandry) was studied at the Chengdu Research Base for Giant Panda Breeding, and Chengdu Zoological Park, China. We monitored the fecal steroid profiles of seven females by radioimmunoassay in order to understand how the different mating groupings affect the animals' reproductive success. Of the seven females studied, all gave birth except the one that was kept in the polyandrous group. Although fecal estradiol metabolites exhibited several peaks during estrus, only one coincided with mating behavior. Fecal progesterone metabolites did not display a sustained rise in the absence of mating behavior, even though estradiol displayed a peak of secretion. This suggests that the red panda may be an induced ovulator. During gestation, fecal progesterone metabolites were maintained at a comparatively high level, and were much higher than those of nonpregnant females. The female in the polyandrous group showed an abnormal estradiol metabolite profile, with a level that was four to five times higher than those of the females in the polygynous groupings. It was observed that this female always escaped and hid in the trees to avoid courtships with males, and did not give birth. This phenomenon suggests that polyandrous groupings may be unsuitable for successful reproduction in captivity. Zoo Biol 24:169–176, 2005. © 2005 Wiley‐Liss, Inc. 相似文献
984.
家蚕转基因载体pBacA3EG的构建及其表达 总被引:2,自引:0,他引:2
以家蚕Bombyx mori肌动蛋白A3(actin 3)启动子、增强性绿色荧光蛋白(enhanced green fluorescent protein, EGFP)基因及SV40的多聚腺苷酸识别序列为元件,经多次克隆,将其插入到piggyBac转座载体中。经PCR、酶切鉴定及测序表明各元件已按正确的方式插入到piggyBac载体中。将构建好的piggyBac表达载体显微注射到胚盘形成前期的蚕卵中,在胚胎早期发育的第3天,通过体视荧光显微镜检测到蚕卵内发出较强的绿色荧光。结果表明该载体构建正确且能在蚕卵中进行表达。家蚕转基因载体的体外瞬时表达不但是成功进行家蚕转基因所必需的第一步,而且其自身也可以应用于基因的功能研究,为家蚕后基因组研究奠定了基础。 相似文献
985.
Jae-Sam Hwang Hyun-Jeong Go Tae-Won Goo Eun-Young Yun Kwang-Ho Choi Su-Il Seong Jong-Su Chang Sang-Mong Lee Bong-Hee Lee Ik-Soo Kim Nam Soon Kim Taehoon Chun Seok-Woo Kang 《Biotechnology letters》2005,26(19):1469-1473
LIM protein cDNA, from Bombyx mori that contains an open reading frame of 622 bp encoding 94 amino acids, was identified and characterized. The B. mori LIM protein homologue is classified into group 2 LIM proteins that contain glycine-rich LIM domain. B. mori LIM protein mRNA is up-regulated at late embryogenesis and detected in the mid-gut of 5th instar larvae. 相似文献
986.
987.
Tager AM LaCamera P Shea BS Campanella GS Selman M Zhao Z Polosukhin V Wain J Karimi-Shah BA Kim ND Hart WK Pardo A Blackwell TS Xu Y Chun J Luster AD 《Nature medicine》2008,14(1):45-54
Aberrant wound-healing responses to injury have been implicated in the development of pulmonary fibrosis, but the mediators directing these pathologic responses have yet to be fully identified. We show that lysophosphatidic acid levels increase in bronchoalveolar lavage fluid following lung injury in the bleomycin model of pulmonary fibrosis, and that mice lacking one of its receptors, LPA1, are markedly protected from fibrosis and mortality in this model. The absence of LPA1 led to reduced fibroblast recruitment and vascular leak, two responses that may be excessive when injury leads to fibrosis rather than to repair, whereas leukocyte recruitment was preserved during the first week after injury. In persons with idiopathic pulmonary fibrosis, lysophosphatidic acid levels in bronchoalveolar lavage fluid were also increased, and inhibition of LPA1 markedly reduced fibroblast responses to the chemotactic activity of this fluid. LPA1 therefore represents a new therapeutic target for diseases in which aberrant responses to injury contribute to fibrosis, such as idiopathic pulmonary fibrosis. 相似文献
988.
Nayoung Kim Soo‐Heon Park Geom Seog Seo Sang Woo Lee Jae Woo Kim Kwang Jae Lee Won‐Chang Shin Tae Nyeun Kim Moo‐In Park Jong‐Jae Park Su Jin Hong Ki‐Nam Shim Sang Wook Kim Yong‐Woon Shin Young‐Woon Chang Hoon Jai Chun Ok‐Jae Lee Won‐Joong Jeon Chan‐Guk Park Chang‐Min Cho Cheol Hee Park Sun Young Won Gin Hyug Lee Kyung Sik Park Jeong Eun Shin Heung Up Kim Joon Yong Park Hiun Suk Chae Geun Am Song Jae Gyu Kim Byung Chul Yoon Sangyong Seol Hyun Chae Jung In‐Sik Chung 《Helicobacter》2008,13(6):542-549
Background and Aims: Lafutidine is a novel H2‐receptor antagonist with gastroprotective activity that includes enhancement of gastric mucosal blood flow. The aim of the present study was to test the efficacy of 7‐ or 14‐day lafutidine–clarithromycin–amoxicillin therapy versus a lansoprazole‐based regimen for Helicobacter pylori eradication. Methods: Four hundred and sixty‐three patients with H. pylori‐infected peptic ulcer disease were randomized to one of four regimens: (1) lafutidine (20 mg b.i.d.), clarithromycin (500 mg b.i.d.) and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LFT group) or (2) for 14 days (the 14LFT group); (3) lansoprazole (30 mg b.i.d.), clarithromycin (500 mg b.i.d.), and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LPZ group); or (4) for 14 days (the 14LPZ group). The eradication rates, drug compliance, and adverse effects among the four regimens were compared. Results: The eradication rates by the intention‐to‐treat and per‐protocol analyses in the 7LFT and 7LPZ groups were 76.5% and 81.6%, and 76.9% and 82.0% (p = .94 and .95), respectively. The eradication rates by intention‐to‐treat and per‐protocol analyses in the 14LFT and 14LPZ groups were 78.2% and 82.2%, and 80.4% and 85.9% (p = .70 and .49), respectively. The treatment duration for 7 days or 14 days did not affect the eradication rates. In addition, the adverse effect rates and discontinuation rates were similar among the four groups. Furthermore, the ulcer cure rate and symptom response rate were similar in the lafutidine and lansoprazole groups. Conclusion: The results of this study showed that lafutidine–clarithromycin–amoxicillin therapy was a safe and effective as lansoprazole‐based triple therapy for the eradication rate of H. pylori, and could be considered as an additional treatment option. 相似文献
989.
Diversity of bacterial community in freshwater of Woopo wetland 总被引:1,自引:0,他引:1
Keun Sik Baik Seong Chan Park Eun Mi Kim Kyung Sook Bae Jae-Hyung Ann Jong-Ok Ka Jongsik Chun Chi Nam Seong 《Journal of microbiology (Seoul, Korea)》2008,46(6):647-655
Diversity of bacterial community in water layer of Woopo wetland was investigated. Cultivable bacterial strains were isolated
by the standard dilution plating technique and culture-independent 16S rRNA gene clones were obtained directly from DNA extracts
of a water sample. Amplified rDNA restriction analysis (ARDRA) was applied onto both of the isolates and 16S rRNA gene clones.
Rarefaction curves, coverage rate and diversity indices of ARDRA patterns were calculated. Representative isolates and clones
of all the single isolate/clone phylotype were partially sequenced and analyzed phylogenetically. Sixty-four and 125 phylotypes
were obtained from 203 bacterial isolates and 235 culture-independent 16S rRNA gene clones, respectively. Bacterial isolates
were composed of 4 phyla, of which Firmicutes (49.8%) and Actinobacteria (32.0%) were predominant. Isolates were affiliated with 58 species. Culture-independent 16S rRNA gene clones were composed
of 8 phyla, of which Proteobacteria (62.2%), Actinobacteria (15.5%), and Bacteroidetes (13.7%) were predominant. Diversity of 16S rRNA gene clones originated from cultivation-independent DNA extracts was higher
than that of isolated bacteria. 相似文献
990.