Analysis of the Offspring Sex Ratio of Chicken by Using Molecular Sexing

The overall sex ratio of offspring （dead embryos and hatch chicks） from all the fertilized eggs of 140 hens collected for 30 days was studied using duplex PCR of certain fragments of sex chromosomes. Additional 894 dead embryos over a period of 21 days of incubation were also investigated to verify the sex ratio of the dead embryos. The sex of the early dead embryos was identified using this molecular sexing technique. The sex ratio of the hatch chicks and the total offspring of the hens investigated in this experiment did not differ from the expected sex ratio （i.e., 1：1）., However, the number of female dead embryos was significantly more than that of males. The data indicated that the different physiologic function of males and females contributed to female-biased mortality during incubation. It was also found by further analysis that the sex ratios of the offspring of some hens were significantly biased to female or male over the period investigated, which suggested that the sex ratio of offspring might be influenced by the maternal condition to some degrees.     

基于母体血浆胎盘源及胚胎源核酸分子的早期妊娠诊断及早期胎儿性别鉴定技术

动物早期妊娠诊断及早期胎儿性别鉴定是繁殖技术中的关键技术.奶牛早期妊娠诊断可及时消除配种后假孕、妊娠后假发情等不利因素,胎儿性别早期鉴定可提高母牛犊的出生比例.近年来,随着孕妇血浆/血清中的胎儿源性游离DNA及胎盘源性游离RNA的发现,使人的早期性别鉴定技术及产前早期诊断技术的研究取得突破性进展;同时也使胎盘特异性表达基因的无创伤性研究成为可能.这些均为单胎动物,特别是奶牛的早期妊娠诊断及早期性别鉴定技术提供了理论依据及技术支持.     

主成分分析法与聚类分析法在胎衣不下奶牛血液生化研究中的应用

通过分析胎衣不下奶牛血液生化指标的变化特征,为奶牛胎衣不下早期诊断方法的建立提供依据。产犊后立即无菌采集47头奶牛血液,其中25头为胎衣正常排出奶牛,22头为胎衣不下奶牛;血液生化分析仪检测血清生化指标,主成分分析法与聚类分析法分析检测结果。结果表明,16项血清生化指标被聚类成3个主成分,主成分聚类分析的结果与临床采集样品的分类结果一致;与胎衣正常排出奶牛相比,胎衣不下奶牛的血清中乳酸脱氢酶、谷草转氨酶、谷氨酰胺转移酶、肌酸激酶水平显著升高。表明,主成分分析和聚类分析可以有效地区别胎衣不下奶牛血清和胎衣正常排出奶牛血清,因此可以通过此方法对奶牛产后胎衣不下的发生进行提前诊断;还表明奶牛胎衣不下的发生不仅与蛋白质代谢、离子代谢和肌肉代谢紊乱有关,而且肝脏和肾脏的机能损伤也可能导致胎衣不下。     

梅山猪胎儿成纤维细胞的分离培养及SRY-PCR法快速性别鉴定

对梅山猪胎儿成纤维细胞的分离培养及性别快速鉴定进行研究,为开展猪体细胞克隆、诱导多能干细胞获取及转基因等提供素材。通过取组织块培养法和胰蛋白酶消化培养法均成功得到梅山猪的胎儿(胎龄35 d)成纤维细胞,取其中7个梅山猪(msz4、msz5、msz6、msz9、msz11、msz14和msz15)胎儿的原代成纤维细胞,在传代培养至第5代时收集贴壁生长的细胞,提取基因组DNA。再利用根据SRY及ZFY/X设计的共2对引物进行PCR反应,扩增后进行琼脂糖凝胶电泳,出现166 bp和445/447 bp两条带的为雄性,只有445/447 bp一条带的为雌性。结果表明梅山猪的细胞系msz6、msz9和msz14为雌性细胞系,而msz4、msz5、msz11及msz15为雄性细胞系。试验结果证明了该方法可应用于鉴定不同培养方法获得猪成纤维细胞的性别,可为试验后期的转基因细胞制备提供性别依据。     

中国古代农民年需用铁量的调查研究

通过访问调查20世纪30～50年代初期的著名铁匠家族,得出了无铁制农业机械时代农民正常生产年需用铁量为0.64市斤的可靠数据。这个数据可成为深层次分析研究中国古代政治、经济问题和生产力水平问题的必要参数,也是破解中国封建社会长期延续问题的必要条件。     

Sex ratio of sea turtles: seasonal changes

Sex ratios of hatchling loggerhead turtles Caretta caretta taken from South Carolina and Georgia ranged from no females in nests laid in late May to 80 percent females in those laid in early July; the sex ratio decreased to 10 percent females in nests laid in early August. These seasonal changes are consistent with the role of temperature in directing sexual differentiation in various reptiles. The data have implications for understanding the demography of sea turtles and for their conservation.     

Postpartum psychiatric reactions: time of onset and sex ratio of newborns

There is no predominance of male infants born to women who develop schizophrenic symptomns with in 1 month after delivery. Moreover, there is no difference in the sex ratio of infants born to schizophrenic women whose onset of symptoms occurred within the first 10 days postpartum, which is the period of rapid hormonal changes that is most likely to reflect postnatal influences of fetal sex.     

Phase separation scenario for manganese oxides and related materials

Recent computational studies of models for manganese oxides have revealed a rich phase diagram, which was not anticipated in early calculations in this context performed in the 1950s and 1960s. In particular, the transition between the antiferromagnetic insulator state of the hole-undoped limit and the ferromagnetic metal at finite hole density was found to occur through a mixed-phase process. When extended Coulomb interactions are included, a microscopically charged inhomogeneous state should be stabilized. These phase separation tendencies, also present at low electronic densities, influence the properties of the ferromagnetic region by increasing charge fluctuations. Experimental data reviewed here by applying several techniques for manganites and other materials are consistent with this scenario. Similarities with results previously discussed in the context of cuprates are clear from this analysis, although the phase segregation tendencies in manganites appear stronger.     

体外培养枫径猪胚胎成纤维细胞系方法的建立

选取枫径猪胚胎,采用胶原酶消化培养法制备猪胚胎成纤维细胞,经数次传代培养及冷冻复苏试验表明胚胎成纤维细胞仍具有正常的传代能力。在体外培养至15代后成纤维细胞核型正常,符合体细胞克隆转基因的要求。用PCR方法建立了枫径猪胚胎成纤维细胞性别鉴定的反应体系,对其中6株细胞进行了性别鉴定。     

现代汉语领主句研究：回顾与前瞻

领主句是现代汉语中的一种特殊句式,因其特殊的句法构造,该句式分别在20世纪50年代、80年代末及近年来三度引起研究者的广泛关注。分析了这三个阶段领主句研究的特点及存在的问题,并依此对领主句未来的研究方向进行了展望。     

Sex-linked genetic influence on caste determination in a termite

The most ecologically successful and destructive termite species are those with both a nymph caste and an irreversibly wingless worker caste. The early developmental bifurcation separating these castes is widely accepted to be strictly environmentally determined. We present evidence that genotype also influences this process. Offspring from four different crosses of nymph- and worker-derived secondary reproductive individuals had strongly differentiated caste and sex ratios, despite uniform rearing conditions. These data fit an X-linked, one-locus-two-allele model. Of five possible genotypes, one was lethal, two resulted in workers, and two resulted in either nymphs or environmentally determined workers. Caste is thus controlled both by environment and by a complex genetic inheritance pattern.     

山羊早期胎儿组织TET1与Wnt通路基因的表达变化及其相关性

【目的】通过检测TET1和Wnt信号通路相关基因以及DKK家族基因在山羊胎儿发育早期的表达变化,分析TET1与Wnt通路基因的相关性,为TET1调控山羊胎儿发育研究提供理论依据。【方法】选取12只健康大足黑山羊母羊,自然发情后与同一只种公羊自然交配。采用剖腹产手术的方法,分别获得妊娠20、25、30、60和90d的胎儿,对胎儿的生长指标(体重、体长)进行统计,并采集了60和90d胎儿的组织器官样品(心、肝、肺、肾、脑、皮肤),通过Real-time PCR(RT-PCR)检测各样品中TET1基因,DKK家族基因(DKK1、DKK2、DKK3)和Wnt家族基因(Wnt2、Wnt2b、Wnt4、Wnt5a、Wnt5b、Wnt7b、Wnt16)的相对表达量。利用SPSS软件分析山羊胎儿发育早期不同阶段TET1与WNT信号通路相关基因相关性以及基因表达显著性(P0.05)。【结果】山羊妊娠早期胎儿生长在60d后有显著变化。荧光定量检测结果表明,TET1基因表达随妊娠天数的增加呈上升趋势。Wnt家族基因在山羊胎儿发育中都检测到表达(Wnt2,-2b,-4,-5a,-5b,-7b,-16)。其中,Wnt2和Wnt7b表达量随胎儿发育逐渐增高;Wnt2b、Wnt5a、Wnt5b、Wnt7b在妊娠30 d时有显著高表达(P0.05);Wnt4在胎儿发育20 d时表达显著(P0.05);Wnt16基因在妊娠25 d有显著高表达(P0.05)。DKK家族基因表达检测结果显示,DKK1在胎儿发育早期阶段都有表达,DKK2/3在妊娠初期表达量较低,后期表达增高。通过组织中基因表达检测显示,TET1在90d胎儿肝、肺、肾和脑中的表达水平相比于60d胎儿组织升高,肝中表达量显著(P0.05)。Wnt家族基因Wnt2在组织器官中有相对活跃的表达,妊娠90d胎儿肺中表达量极显著(P0.01);Wnt16基因在胎儿皮肤组织中表达显著(P0.05),且维持在一个较高的水平;Wnt5a和Wnt7b在肾中表达显著(P0.05),其他Wnt基因在组织中都有表达。相关性分析显示,胎儿生长指标(体重、体长)变化与TET1的表达呈极显著正相关(P0.01);TET1在胎儿发育早期的表达与Wnt2、Wnt7b、Wnt16呈现正相关,与Wnt2b、Wnt4、Wnt5a、Wnt5b呈负相关,其中与Wnt5b呈显著负相关(P0.05),与Wnt7b呈极显著正相关(P0.01)。Wnt通路基因之间也有相互关系,Wnt2与Wnt4呈极显著负相关(P0.01)。Wnt2与Wnt7b,Wnt2b与Wnt5a、Wnt5b,Wnt5a与Wnt5b呈极显著正相关(P0.01)。Wnt4与Wnt5a呈显著正相关(P0.05)。【结论】获得了TET1与Wnt基因在山羊胎儿发育早期的表达模式,并进行了相关性分析,填补了这些基因在山羊方面的研究空白;TET1与Wnt基因对山羊胎儿早期的发育和组织的形成是一个动态的调控变化过程;TET1基因表达与部分Wnt基因呈现显著正相关,部分呈现显著负相关;Wnt通路基因之间表达量呈现一定的相关性。这些数据为TET1与Wnt分子调控山羊早期胎儿发育的机制深入研究提供了参考。     

应用牙釉质基因鉴定绒山羊早期胚胎的性别

采用酚-氯仿法和煮沸法从南疆绒山羊血液和早期胚胎中提取基因组DNA,分别以雄羊和雌羊的血液基因组DNA和早期胚胎基因组DNA(约20～30胚胎细胞)为模板,以AMEL引物进行PCR扩增和电泳分析.结果表明:绒山羊5ng量和10pg量血液基因组DNA经扩增后雌性只得到1条非特异性带,雄性得到1条非特异性带和1条特异性带;超微量血液基因组DNA样本(10pg)经巢式扩增和电泳分析能够鉴定绒山羊性别;32枚绒山羊胚胎鉴定结果,雄雌性别比17/15;移植胚胎产羔雄雌比15/14.采用牙釉质基因(AMEL),经巢式扩增和电泳分析能够鉴定绒山羊性别,并对胚胎无损伤;南疆绒山羊早期胚胎性别鉴定结果与胚胎移植后产羔性别结果对比,雌雄性别比率差异不显著(P>0.05).     

Ecology and catastrophic mortality in wild horses: implications for interpreting fossil assemblages

The identities, sexes, and reproductive status of groups of wild horses (Equus caballus) living in the Great Basin Desert of North America were known prior to their deaths on ridgelines. Another group of very young horses died on a quagmire. Snow accumulation or drought was apparently responsible for the mass deaths. These data have implications for reconstructing some aspects of the social structure of fossil mammals on the basis of skewed sex or age ratios in bone assemblages.     

淮河流域中游湿地景观格局指数变化分析

利用淮河流域中游20世纪50年代的地形图和1980、2000年的遥感影像图分别提取、解译得到各时期的土地利用图和基于湿地二级分类的各湿地类型分布图,运用景观指数分析方法对淮河流域中游湿地景观生态变化进行分析评价。分析结果表明：1950~1980年湿地景观格局指数变化大,1980~2000年湿地景观格局指数变化很小。这些湿地景观格局指数的变化总体上说明淮河流域中游湿地格局由多样化、复杂性转为单一化、破碎性,湿地系统组分急剧减少、过渡带大量消失,湿地景观的连通性、异质性大大减弱,湿地系统的完整性、均衡性不复存在,从而导致湿地生态服务功能下降或不能得到充分利用。     

湘西州森林防火与气象条件关系

利用1950~1988、2005~2015年湘西州森林火灾相关资料,1960~2015年湘西州8县(市)气象观测站温度、湿度资料,采用线性和曼-肯德尔(MK)突变检验的分析方法,对湘西州森林防火与气象条件关系进行研究。通过研究得出气象条件和森林火灾关系非常紧密,每年的春冬季节是森林火灾的高发期;确定森林火险预报模型为I=D×4+(100-H)×0.4+T+F+r,将森林火险等级划分为五级;对湘西州森林防火预警预报系统进行研发,将森林防火气象预报预警模型与突发事件预警信息发布的业务充分融合。     

Transplantation of fetal hematopoietic stem cells in utero: the creation of hematopoietic chimeras

Transplantation of normal, immature, fetal hematopoietic cells into a preimmune fetal recipient with a congenital hemoglobinopathy may allow partial reconstitution of normal hemoglobin production without the complications associated with postnatal bone marrow transplantation (immunosuppression and the occurrence of graft versus host disease). In order to test this hypothesis the naturally occurring polymorphism at the beta-hemoglobin locus of the sheep was used as a marker for engraftment and hematopoietic chimerism. Intraperitoneal injection of allogeneic fetal stem cells into normal fetal lambs resulted in hematopoietic chimerism in three of four surviving recipients. This chimerism has been sustained for 6 months after birth and 9 months after engraftment, without evidence of graft versus host disease, and without the use of immunosuppressive therapy.     

粤北低山丘陵地区小红栲生长过程分析

本文根据务必粤北低山丘陵地区收集小红栲解析木１２株和标准木３１株的资料，通过建立生长模型，分析其生长规律，并用最优分割法将小红栲生长发育过程分为５个阶段，据此进一步划分其龄级和组织龄组。结果表明，小红栲早期的树高和直径生长迅速，继而进入材积束生期和数量成熟期，从面提供该树种的营林理论论依据。     

枣粘虫成虫性引诱的初步研究

枣粘虫是我国红枣产区的重要害虫。为探求防治新途径,对成虫生物学与性引诱进行了初步研究。枣粘虫一年发生三代,各代成虫发生的始、盛、末期分别为:第一代3/上——4/上—4/下;第二代6/上——6/中——6/下;第三代7/上——7/下——8/中。雌雄性比在0.86∶1和1.19∶1之间。一般雄蛾羽化早於雌蛾。95％以上成虫集中于早晨5——8时进行交尾。雌雄多次交尾,雌蛾平均1.48次,雄蛾3次。成虫寿命一般为一周左右,雌蛾寿命长於雄蛾。田间性诱试验表明:活雌蛾性诱以3头和5头的雌当量效果最好;粗提液以乙醚为溶剂的诱蛾数量最高;摘取腺体以羽化后48小时摘取的诱捕效果较好。通过对雌蛾性腺体所产生的性信息素进行EAG——GC以及色质联仪分析,初步确定枣粘虫性信息素的成份是一元不饱和十二碳烯醇乙酸酯的多元体系。经微量臭氧化测定,双键位置在7位和9位。田间生测表明以反、顺——9——十二碳烯醇酯(E、Z——9—C_(12)∶OAC)在比例为80∶20和83∶17时对雄蛾的诱捕效果最高。     

Subplate neurons pioneer the first axon pathway from the cerebral cortex

During the development of the nervous system, growing axons must traverse considerable distances to find their targets. In insects, this problem is solved in part by pioneer neurons, which lay down the first axonal pathways when distances are at a minimum. Here the existence of a similar kind of neuron in the developing mammalian telencephalon is described. These are the subplate cells, the first postmitotic neurons of the cerebral cortex. Axons from subplate neurons traverse the internal capsule and invade the thalamus early in fetal life, even before the neurons of cortical layers 5 and 6, which will form the adult subcortical projections, are generated. During postnatal life, after the adult pattern of axonal projections is firmly established, most subplate neurons disappear. These observations raise the possibility that the early axonal scaffold formed by subplate cells may prove essential for the establishment of permanent subcortical projections.