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刘晓光 《Canadian Metallurgical Quarterly》2011,39(9)
[目的]研究蒙古绵羊胚胎大肠黏膜上皮的组织发生.[方法]利用组织学常规方法.[结果]蒙古绵羊胚胎大肠黏膜上皮的发育经历了单层细胞到复层细胞再到单层细胞的过程;杯状细胞在37 mm胚初见;90 mm胚直肠腺开始发育,142 mm胚盲肠、结肠肠腺开始发育.[结论]蒙古绵羊胚胎大肠黏膜上皮经历了单层细胞到复层细胞再到单层细胞的发育过程. 相似文献
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[目的]研究月见草大孢子发生与雌配子体发育的规律.[方法]利用传统石蜡切片法对月见草大孢子发生及雌配子体发育进行了研究.[结果]雌蕊由四心皮组成,中轴胎座,胚珠倒生,体积小、数量多,双珠被、厚珠心.珠心内侧一细胞发育为初生造孢细胞,初生造孢细胞经过减数分裂形成线形排列的大孢子四分体,合点端3个大孢子退化,珠孔端的一个作为功能大孢子发育成为单核胚囊,经2次连续的有丝分裂形成四核的胚囊.[结论]月见草胚囊发育属于待宵草型. 相似文献
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李贵节 《Canadian Metallurgical Quarterly》2011,28(3)
本研究通过观察籼型杂交水稻"川优9527"'的花粉和药室壁的发育,对幼穗花药从雄蕊原基形成至花粉成熟的全过程进行了分期.选用不同发育时期的水稻幼穗(长度约1.0~10.0 mm),以石蜡切片技术分别制作其花药装片,置于光学显微镜(Nikon DS-Ri1-U2)下观察并拍照.根据细胞及组织形态特征的显著变化,将花药的发育进程精细划分为:孢原细胞期、二层药室壁期、三层药室壁期、花粉母细胞形成期(以上4期对应小孢子母细胞形成期)、花粉母细胞减数分裂初期、花粉母细胞减数分裂中期、花粉母细胞二分体时期、花粉母细胞四分体时期(以上4期对应小孢子母细胞减数分裂期)、小孢子早期、小孢子中期、小孢子晚期、二胞花粉时期、成熟花粉时期等13个阶段. 相似文献
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[目的]研究卵泡微环境对颗粒细胞与卵母细胞质量及体外受精胚胎发育的影响.[方法]从不同直径大小的卵泡中收集卵母细胞和颗粒细胞.Hoechst33342 染色观察卵母细胞核形态;采用Annexin-V-FITC/PI法染色、流式细胞仪检测颗粒细胞的凋亡情况;进行受精卵体外培养,并计算受精率及受精卵的囊胚率.[结果]大卵泡(>10 mm)和小卵泡(<3 mm)内颗粒细胞凋亡率明显高于3~7和7~10 mm卵泡内的颗粒细胞凋亡率(P<0.05)大卵泡和小卵泡内的大量卵母细胞呈现出染色质固缩、核碎裂及胞浆浓缩等凋亡特征.3~7和7~10 mm卵泡内的卵母细胞成熟率明显高于大卵泡和小卵泡(P<0.05).来源于不同直径卵泡的卵母细胞,其卵裂率和囊胚率差异均不显著.[结论]卵泡微环境是影响牛胚胎体外生产的主要环节.直径为3~10 mm卵泡内颗粒细胞质量及卵母细胞的体外成熟率较高,卵泡直径对卵母细胞受精及受精卵的早期发育没有影响. 相似文献
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[目的]为生产转基因克隆猪奠定基础.[方法]以反转录病毒转染的带有红色荧光蛋白(RFP)基因的猪胎儿成纤维细胞作为核移植的核供体,利用体细胞克隆技术研究红色荧光蛋白克隆胚胎体外发育情况.[结果]RFP转基因细胞的融合率为83.87%,与未转基因细胞(80.56%)相比无显著差异(P>0.05);RFP转基因体细胞重构胚体外囊胚率为8.67%,与未转基因细胞组(6.56%)相比无显差异著(P>0.05);RFP转基因体细胞重构胚移植于15头受体后,尚无受孕个体.[结论]利用转红色荧光蛋白基因的细胞为供体细胞,能够成功克隆出转基因胚胎,并获得转基因囊胚. 相似文献
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[目的]在输卵管上皮细胞和/或垂体细胞饲养层下培养小鼠孤雌胚胎,探讨促进小鼠孤雌胚发育突破2-cell阻滞的机制,建立完善的培养体系.[方法]复式激活小鼠卵母细胞后分别在不同饲养层的CZB培养液中进行培养,并观察、比较各培养条件下孤雌胚胎的发育情况.[结果]培养至24 h,各组无显著差异,都有较高卵裂率.培养至48 h,2类饲养层细胞下的孤雌胚胎4~8-cell发育效果好,与单独一类饲养层细胞培养差异显著,与对照组比较差异极显著.培养至96 h,2类饲养层细胞下有49.4%(42/85)孤雌胚胎发育为桑囊胚,与其他各组比较差异极显著.[结论]含有输卵管上皮细胞+垂体细胞的CZB培养液可有效促进小鼠孤雌胚胎发育突破2-ceU阻滞,并进一步提高其发育率. 相似文献
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[目的]为进一步研究粘细菌中生物活性物质奠定基础.[方法]从成都各区县采集35份水样、土样、兔粪、羊粪、风化岩石以及朽木样品,预处理后使用不同方法进行分离纯化,观察分离粘细菌的营养细胞、粘孢子、子实体和菌落形态等特征,并进行鉴定归属.[结果]共分离纯化得到42 株粘细菌,鉴定为粘球菌属、囊球粘细菌属、粒状粘细菌属、堆囊粘细菌属、蜂窝粘细菌属、标桩菌属和原囊粘细菌属,共7个属.其中,水样中粘细菌的出菌率最高.[结论]水样中有丰富的粘细菌资源. 相似文献
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[目的]研究抗松针褐斑病湿地松子代组培苗瓶内菌根化.[方法]对湿地松再生植株离体条件下菌根的形成进行了研究,并对再生植株的生长状况进行了观察.[结果]菌根真菌培养基质和接种量对离体条件下菌根的形成有较大影响湿地松丛生芽诱导出根原基后,以转接到珍珠岩为培养基质接种彩色豆马勃为最佳,有利于菌根的形成;在珍珠岩接种彩色豆马勃为2个菌块时,菌根化率高达84.4%,形成的二叉分枝状短根最多,平均每条主根上形成12.49条;菌根的形成提高了再生植株的驯化移栽成活率,菌根化再生植株在植物生长室长势良好,根系发达.[结论]为提高抗松针褐斑病湿地松组培再生植株的成活平提供了依据. 相似文献
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[目的]探讨新疆喀喇昆仑山几种苔藓植物的细胞学及孢子萌发.[方法]用显微镜观察了新疆喀喇昆仑山3种藓类植物的染色体数目,并通过光学显微镜观察,描绘和分析了另2种藓类孢子萌发的基本过程、萌发能力及发育的特点.[结果]新疆喀喇昆仑山3种 藓类植物染色体数目为:长尖叶赤藓,n=7;赤茎藓,n=5;狭网真藓,n=10,其中长尖叶赤藓和狭网真藓的染色体数目为国内首次报道.光学显微镜观察表明,卵叶盐土藓的孢子呈不规则球形,深棕色,不透明,为单细胞型孢子,接种7 d后,孢子萌发率可达62%.美姿藓的孢子呈椭圆形,黄绿色,较透明,为单细胞型孢子,接种7 d后,孢子的两极萌发率达42%.[结论]与卵叶盐土藓相比,美姿藓孢子萌发表现明显的极向,一般为单、双极. 相似文献
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贾春生 《Canadian Metallurgical Quarterly》2011,39(3)
[目的]分离鉴定萝卜蚜的病原真菌,并测定其对萝卜蚜的致病性.[方法]采用形态学方法进行病原真菌种类鉴定,利用孢子浴方法对萝卜蚜进行致病性测定.[结果]初生分生孢子,卵形,双囊壁,单核,(24.7±1.4)μm×(10.7±0.9)μm, L/D=2.3±0.2.次生分生孢子形似初生分生孢子,大小为:(18.6±2.1)μm×(13.3±1.3)μm,L/D=1.4±0.2.菌丝段菌丝状,直径为(10.6±0.8)μm.分生孢子梗掌状分枝,直径(10.0±0.9)μm 假囊状体不分枝,基部粗大,直径(19.2±1.7)μm,向端部渐尖,直径(8.0±0.9))μm.假根单菌丝状,基部直径(21.0±3.0)μm,底端具有规则的盘状固着器.休眠孢子未见.该菌对萝卜蚜的致死中量为18.21 cfu/mm2.[结论]感染萝卜蚜的昆虫病原真菌被鉴定为新蚜虫疠霉, 该菌对萝卜蚜表现出较强的致病性. 相似文献
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通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。 相似文献
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K Ohta M Nishi M Ueda S Ohyama T Matsubara T Takahashi T Nakajima 《Canadian Metallurgical Quarterly》1998,99(9):589-594
Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients. 相似文献
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Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed. 相似文献
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TA Solokhina LS Shevchenko IuV Se?ku EG Rytik LV Besedina TS Veshchugina 《Canadian Metallurgical Quarterly》1998,98(6):42-46
Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined. 相似文献
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