998 resultados para 16-159


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The central nervous system exhibits remarkable plasticity in early life. Prenatal morphine exposure may induce adverse behavioral effects on the neonate and the developing offspring. In the present study, we investigated the effect of prenatal morphine exposure (daily from embryonic days 12-16, 20 mg/kg) on 11-day-old chicks using two forms of spatial paradigms: one trial detour behavior task in which animals must bypass an obstacle to reach the desired goal without any training and detour learning task which required several trials of training to reach the detour criterion. The results showed that, on the condition that chicks could successfully detour in the first trial, morphine exposed chicks exhibited longer detour latency to finish the task, coupled by a preference for turning right versus turning left. In contrast, no significant difference in learning and memory was found in detour learning task between morphine exposed chicks and saline chicks. These findings suggest specific behavioral changes associated with prenatal exposure to opioids during mid to late gestation, also raise attention to the possible health hazard from pregnancy drug use in everyday life. (C) 2010 ISDN. Published by Elsevier Ltd. All rights reserved.

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选用婆罗门牛和BMY牛供体超数排卵,以第1次人工授精(AI)当日为0 d,分别在AI第6~6.5天、7~7.5天和8~8.5天回收胚胎,统计≤16细胞胚、桑椹胚、囊胚和孵化胚的数量,计算各发育阶段胚胎所占的百分率,分析婆罗门牛和BMY牛的胚胎回收适期.结果表明:婆罗门牛AI第6~6.5天的桑椹胚率比BMY牛高43.54个百分点(P<0.01),AI第8~8.5天的孵化胚率比BMY牛高35.94个百分点(P<0.05),胚胎发育速度比BMY牛较快.罗门牛和BMY牛在AI第6~6.5天回收胚胎的囊胚率低,而第8~8.5天的孵化胚率高,胚胎回收以AI第7~7.5天为宜.

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下载PDF阅读器2005年8月初,对西藏藏北54头3~12岁受体母牦牛实施了同期发情试验,外源激素分别采用促排卵素LHRH-A3结合孕马血清PMSG处理法和氯前列腺素(PGF2α)两次注射处理法.结果表明:LHRH-A3+PMSG法处理6~9岁和10~12岁牦牛时发情率(可移植率)分别为93.3%(40%)和60%(20%),二次PGF2α法处理3~5岁、6~9岁、10~12岁牦牛时发情率(可移植率)分别为61.1%(5.5%)、70%(40%)和50%(16.7%).结论:LHRH-A3+PMSG法和二次PGF2α法都是成功的同期处理方法,受体在6~9岁时同期效果最好.

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为了比较婆罗门牛和BMY牛的雌二醇(E2)、孕酮(P4)水平及胚胎生产潜力,并探讨MOET技术在BMY牛扩繁中的应用前景,采用进口激素(日本产FSH 24~36 mg+美国产PG 35 mg)和国产激素(国产FSH 10~12 mg+国产PG 0.8 mg)对全放牧婆罗门牛和BMY牛进行超排,并于超排前(同期发情第7天)、超排开始、超排第3天、超排发情当天和胚胎回收当天采集血液,采用RIA法分析血浆中的E2和P4水平。结果表明,BMY牛的黄体数和获胚(卵)数、可用胚数分别较婆罗门牛高2.09个和0.95、0.36枚,但差异不显著(P>0.05);BMY牛的排卵率较婆罗门牛高18.46%(P<0.01),而可用胚率则较婆罗门牛低2.55%(P<0.01)。BMY牛在5个处理时段的E2和P4平均值分别较婆罗门牛高0.58 pg/mL(P<0.01)和1.44 ng/mL(P>0.05),在各处理时段的P4水平变化规律几乎与婆罗门牛一致,E2/P4值为婆罗门牛的5.16倍。结果提示,BMY母牛的E2和P4水平高于婆罗门牛,在激素水平和繁殖性能方面表现出一定的杂种优势;E2水平低是婆罗门牛发情微弱和排卵率低的主要原因...

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胚胎冷冻保存已广泛用于胚胎移植、动物克隆以及动物资源保护。此技术的应用需保证胚胎在冷冻—解冻后具有较高的成活率。自从1972年小鼠胚胎冷冻保存获得成功以来,许多学者在简化冷冻程序、缩短冷冻时间等方面进行了深入的研究。文章就胚胎冷冻的原理、保护剂、冷冻方法以及解冻方法等方面进行了综述。

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以小鼠原核期胚胎为对象, 以胚胎的存活率、卵裂率、囊胚率以及囊胚细胞数作为检测指标, 在M2 液的基础上添加8 种浓度(0 , 2 , 4 , 8 , 16 , 32 , 64 , 96 mg/ mL) 牛血清白蛋白(BSA) 配置防冻液, 探讨防 冻液和玻璃化冷冻后对胚胎发育的影响。BSA 防冻液对胚胎发育影响的实验结果表明, 8 个浓度组间以及与对 照组间胚胎的卵裂率、囊胚率以及囊胚细胞数无显著差异( P > 0105) , 说明在防冻液中加入一定浓度的BSA 对小鼠胚胎无毒性作用。防冻液经玻璃化冷冻后对胚胎发育影响的实验表明, 8 个浓度组间冷冻胚胎复苏后的 存活率、卵裂率、囊胚率及囊胚细胞数无显著差异( P > 0105) 。表明BSA 在这种防冻液中没有明显的保护作 用。从经济、实用、生物安全角度考虑, 不支持在玻璃化防冻液中添加BSA。

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Participants were exposed to concepts and information about EAFM using a structured, participatory method of delivery. The learning strategy involved specifically designed exercises, using real examples, to consolidate learning. Daily monitoring and reviews were conducted together with pre-and post-course assessment.

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本研究以体外无血清培养的人早期绒毛细胞滋养层细胞和绒毛组织培养为模型,测定了天花粉蛋白对滋养层细胞hCG、孕酮分泌的影响,发现体外无血清培养的细胞滋养层细胞分泌的hCG在天花粉蛋白浓度为0.1μg/ml即下降50%,而后下降缓慢,8μg/ml以上方降为零,而绒毛组织培养在天花粉蛋白浓度为0.1μg/ml时hCG下降近90%,而后下降缓慢,至8μg/ml以上降到零,说明体外培养的细胞滋养层细胞中有两个群体,其中一个对天花粉蛋白敏感,另一个不敏感,尽管在形态上很难区别。孕酮的反应则不同,在细胞滋养层细胞和绒毛组织培养中,随天花粉蛋白浓度升高,孕酮分泌均缓慢下降,未出现两阶段下降过程。

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 报道了30 例正常产妇的初乳和成熟乳的碘含量分别为135165±58128×10- 2 Lmo löL 和54188

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从超数排卵的14只母兔获得438枚受精卵, 卵龄16-22h。显微操作在带微分干涉和相差的Nikon倒置显微镜下进行。注射针的尖端外径0.5#mu#m, 离尖端40和80#mu#m处的外径分别为4.2和6.5#mu#m。注射用外源基因是绵羊生长激素基因与MT-1启动基因藕连的线状DNA溶液(1ng/#mu#l)。140枚注射的受精卵和未注射的145枚受精卵(对照), 在Ham^sF-10培养液(补充生长因子)中培养(38℃, 5%的CO_(2))。结果培养48h后, 注射组卵裂发育率分别是: 未卵裂7.9%(11/140)、卵裂至2-4细胞期11.0%(16/140)、卵裂至8-16细胞期80.7%(113/140)。对照组相应的卵裂率分别是4.1%(6/145)、12.4%(18/145)和83.4%(121/145)。两组卵裂发育率相近。

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Aim: To establish a method for cynomolgus monkey sperm cryopreservation in a chemically defined extender. Methods: Semen samples were collected by electro-ejaculation from four sexually mature male cynomolgus monkeys. The spermatozoa were frozen in straws by liquid nitrogen vapor using egg-yolk-free Tes-Tris (mTTE) synthetic extender and glycerol as cryoprotectant. The effects of glycerol concentration (1%,3%, 5%, 10% and 15% [v/v]) and its equilibration time (10 min, 30 min, 60 min and 90 min) on post-thaw spermatozoa were examined by sperm motility and sperm head membrane integrity. Results: The post-thaw motility and head membrane integrity of spermatozoa were significantly higher (P < 0.05) for 5% glycerol (42.95 +/- 2.55 and 50.39 +/- 2.42, respectively) than those of the other groups (1%: 19.19 +/- 3.22 and 24.84 +/- 3.64; 3%: 34.23 +/- 3.43 and 41.37 +/- 3.42; 10%: 15.68 +/- 2.36 and 21.39 +/- 3.14; 15%: 7.47 +/- 1.44 and 12.90 +/- 2.18). The parameters for 30 min equilibration (42.95 2.55 and 50.39 2.42) were better (P < 0.05) than those of the other groups (10 min: 31.33 +/- 3.06 and 38. 98 +/- 3.31; 60 min: 32.49 +/- 3.86 and 40.01 +/- 4.18; 90 min: 31.16 +/- 3.66 and 38.30 +/- 3.78). Five percent glycerol and 30 min equilibration yielded the highest post-thaw sperm motility and head membrane integrity. Conclusion: Cynomolgus monkey spermatozoa can be successfully cryopreserved in a chemically defined extender, which is related to the concentration and the equilibration time of glycerol.

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球果蝠Sphaerias blanfordi(Thomas,1891)是亚洲南部喜马拉雅-印度支那地区的特有种,甚为罕见而少有报道.曾被认为是单型种,几乎无雄性特征的描述.蔡桂全和张遁治(1980)根据采自西藏东南部墨脱的2只雄性标本订了一亚种一墨脱亚种Sphaerias blanfordi motuoensis,其主要特征是颈下侧有一对灰黄色的圆形毛斑.中国科学院昆明动物研究所先后在云南西北部高黎贡山地区采获25号标本(9♂♂,16♀♀),发现球果蝠两性在外形上有明显的性别差异,雄性的颈下侧有一对圆形、灰黄色的刷状毛斑,但雌性均无;对比墨脱标本,认为墨脱亚种的鉴别特征不可靠,亚种不能成立.Lunde(2003)曾报道采自越南北部Mt.Tay Con Linh Ⅱ地区的43号标本,其前臂长和上犬齿外宽明显与印度、缅甸和云南西北部高黎贡山地区的标本不同,可能是真正的地理亚种.

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采用样方方法对栖息于云南省哀牢山平河(E 101°17′16.1″,N 24°20′09.5″,海拔2 600 m)的黑长臂猿(Nomascus concolor)栖息地乔木层结构进行了调查.调查中共记录到乔木57种隶属于23科37属;木质藤本植物9种隶属于6科8属.优势科主要为杜鹃花科(Ericaceae)、木兰科(Magnoliaceae)、山茶科(Theaceae)和壳斗科(Fagaceae)植物.主要树种重要值排序表明,露珠杜鹃(Rhododendron irroratum)为该地区最主要的优势种,在各坡位中均有广泛分布.乔木的多样性指数、均匀度指数在沟底明显降低,而乔木1层和2层所占的比例以及木质藤本的平均多度均随着坡位的下降而升高.与其他地区的长臂猿相比,哀牢山黑长臂猿的活动程度较低(10-22 m),果实性食物种类较少.

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钝头蛇亚科Pareinae 隶属游蛇科Colubridae分布于10°S—35°N, 80  25 °E的东南亚及其邻近岛屿, 是具有吻钝, 无颏沟和上颌骨前端无齿等特殊性状 的唯一类群、原记载共2属16种。经核实, 该类群共有18种, 分别隶属三个属。 描述了其谱系发育及其与地质演变的关系。图6表2参23

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黑长臂猿通常在上午鸣叫, 多数发生在9:30分以前, 鸣叫起始时间具季节性变化。黑长臂猿平均每两天鸣叫一次, 日鸣叫发生频次在50%左右, 鸣叫的发生也随季节而变化。鸣叫的持续时间无群体的差异, 但群体在不同季节鸣叫时间长短不一, 一个群体的鸣叫并未引起其它群体的鸣叫。