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101.
GeneRegulationofProgrammedCellDeathYangJianminLiuLianrui(InstituteofGenetics,AcademiaSinica,Beijing100101)细胞死亡与细胞生长、分化和增殖一样是维持生物体平衡的重要环节。它是生命过程一个重要组成部分,只在近年来才引起生物学家和医学家的重视.细胞死亡现象称为Apoptosis,或称Programmedcelldeath(细胞程序化死亡),也有称为Suicide(细胞自杀现象)。细胞死亡(apoptosis)是在细胞内和细胞外因子的严格控制下~种有步骤有活性的生理性自行消亡过程,正在死亡的细胞形态上发生明显的变化,如胞浆浓缩,原生质膜形… 相似文献
102.
温泉蛇的染色体组型及Ag-NORs的研究 总被引:4,自引:0,他引:4
曾晓茂 王跃招 方自力 吴贯夫 刘志君 Theodore J.Papenfuss Robert J.MaceyZENG Xiao-Mao WANG Yue-Zhao FANG Zi-Li WU Guan-Fu LIU Zhi-Jun Theodore J.Papenfuss Robert J.Macey 《遗传》1996,18(1):4-6
本文首次报道了温泉蛇(Thermophis baileyi)的染色体组型及Ag-NORs,其核型模式可表达为2n=36=14M+2T+20m, ZW型性决定,Z和W分别为中及亚端部着丝点染色体。该结果与游蛇属种类的核型有较大差异,从而旁证了将温泉蛇从游蛇属中分出的观点。仅一对NOR于No.9染色体长臂并与其次溢痕位置相当,该NOR与锦蛇属种类一致而与游蛇类不同。根据染色体特征,认为温泉蛇在游蛇亚科中处于较为原始的地位。 相似文献
103.
关于群体遗传学一章教学改革的探讨 总被引:1,自引:1,他引:0
教学工作是培养人才的基本手段。随着社会的进步,教育理论也在不断更新。在发达国家,STS(science-technique-society)教育理论(即把科学、技术和社会紧密联系进来)勃然兴起。我们所做尝试,除自身专业特点所决定,就是在这一原则思想指... 相似文献
104.
A complete series of vomerine teeth of pycnodontoidea has been foundfrom the vicinity of Changtu(Sikang).It represents the first record of vertebrateremains in the Tibetan highlands.Order PycnodontoideaFamily CyrodontidaeGenus Tibetodus,new genusDiagnosis as given for the type species Tibetodus gyrodoidesSpecies Tibetodus gyrodoides,new species.Material:A vomer with the teeth nearly complete.Field No.C.3340. 相似文献
105.
YAN YiWu LIU Qiang LI Ning DU JianChao LI Xiao LI Chang JIN NingYi JIANG ChengYu 《中国科学:生命科学英文版》2015,58(2):208-211,1,2
<正>Dear Editor,Since the first recognized case of human infection with avian influenza H5N1 virus in 1997,the worldwide spread and re-emergence of this highly pathogenic influenza virus have led to 694 human infection cases.Of these cases,402died from 2003 to 2015(http://www.who.int/influenza/human_animal_interface/EN_GIP_20150106CumulativeNumber H5N1cases.pdf?ua=1),with a morbidity rate of 相似文献
106.
LIN ZHONGXIANG HAN YALING WU BINGQUAN PANG WEIGANG Department of Cell Biology Beijing Institute for Cancer Research Department of Pathology Beijing Medical University 《Cell research》1990,1(2):141-151
Cytoskeletal changes in transformed cells (LM-51) exhibiting obviously metastatic capabilities were investigated by utilization of double-fluorescent labelling through combinations of: (1) tubulin indirect immuno(?)uorescence plus Rhodamine-phalloidin staining of F-actins; (2) indirect immunofiuorescent staining with actinin polyclonal-and vinculin monoclonal antibodies. The LM-51 cells which showed metastatic index of >50% were derived from lung metastasis in nude mice after suboutaneous inoculation of human highly metastatic tumor DNA transfected NIH3T3 cell transformants. The parent NIH3T3 cells exhibibed well-organized microtubules, prominent stress fibers and adhesion plaques while their transformants showed remarkable cytoskeletal alterations: (1) reduced microtubules but increased MTOC fluorescence; (2) disrupted stress fibers and fewer adhesion plaques with their protein components redistributed in the cytoplasm; (3) Factin- and actinin/vinculin aggregates appeared in the cytoplasm. These aggregates were doe-like, varied in size (0.1--0.4m) and number, located near the ventral surface of the cells. TPA-indueed actin/vinculin bodies were studied too, Indications that actin and actinin/vinculin redistribution might be important alterations involved in the expression of metastatic capabilities of LM-51 transformed cells were discussed. 相似文献
107.
为了解旋扭山绿豆(Desmodium intortum)对低温的耐受性,以在南方各省广泛种植的优质牧草紫花大翼豆(Macroptilium atropurureum)为对照,研究了旋扭山绿豆对低温胁迫的生理响应。结果表明,低温胁迫(4℃)下,旋扭山绿豆的实际光能转化效率(Yield)和光合电子传递效率(ETR)在第2~8天时下降幅度显著低于紫花大翼豆(P0.05)。低温处理使旋扭山绿豆和紫花大翼豆超氧化物歧化酶(SOD)活性显著增加(P0.05);过氧化氢酶(CAT)活性则显著降低;旋扭山绿豆的过氧化物酶(POD)没有显著变化(P0.05),但紫花大翼豆下降了47.11%。低温处理下旋扭山绿豆游离脯氨酸和可溶性糖含量显著高于紫花大翼豆(P0.05)。回归分析、抵抗力指数和营养成分分析表明,旋扭山绿豆是一种抗寒性与营养价值均优于紫花大翼豆的优良牧草,其中Yield、ETR、CAT与渗透调节物质(游离脯氨酸和可溶性糖)可以作为旋扭山绿豆耐寒性鉴定的重要生理指标。 相似文献
108.
ZHANG XinYuan LIU Wei WU ShanShan JIN JingLong LI WeiHong Wang NingLi 《中国科学:生命科学英文版》2015,(1):101-107
Many randomized clinical controlled trials have confirmed the efficacy and safety of calcium dobesilate in treating diabetic retinopathy(DR).This systematic review critically evaluated the evidence that links calcium dobesilate to DR.In this fixed-effects meta-analysis,a total of 221 pertinent English-language articles published between January 1975 and October 2013 were identified.Systematic searches of PUBMED,Springer Link and the Cochrane Clinical Trials Database were conducted using the keywords “diabetic retinopathy” and “calcium dobesilate”.The extracted information included the study design,inclusion and exclusion criteria,setting,sample size,participant mean age,treatment regime,mean change in best corrected visual acuity,laboratory parameters,capillary fragility,intraocular pressure and fundus manifestations based on the findings of fluorescent angiography.The summary statistics indicated that calcium dobesilate was significantly associated with improving retinal microaneurysms(RR: 0.62,95%CI: 0.42?0.90,P=0.01),retinalhemorrhages(RR: 0.39,95% CI: 0.17?0.88,P=0.02); exudates(RR: 0.31,95% CI: 0.12?0.81,P=0.02),reduction of whole blood viscosity(MD: ?0.57 CP,95% CI: ?0.75 to ?0.38,P<0.001),plasma viscosity(MD: ?0.36 CP,95% CI: ?0.63 to ?0.09,P=0.01) and blood cholesterol(MD: ?0.48 mg m L?1,95% CI: ?0.64?0.33,P<0.00001).Intraocular pressure was also significantly reduced(MD: ?5.59 mm Hg,95% CI: ?6.69 to ?4.50,P<0.00001).The results indicate that calcium dobesilate effectively treats DR at the systematic and local ocular levels. 相似文献
109.
Denitrificationis the ability of bacteria to use nitro-gen oxides(NO3-and NO2-)as electron acceptorsto pro-duce gaseous nitrogen,mainly N2.The oxidation of or-ganic material coupled to reduction of oxygen leads to ahigher energy yield than reduction of nitrate.Oxygen iscommonly accepted to be the first choice as electron ac-ceptor[1].Therefore,denitrifying is generally thought toonly occur under almost anaerobic conditions.Anefficientwastewater treatment toremove nitrogen components relieson… 相似文献
110.
The respiration metabolismand excretion of marinebivalves were studied by different researchers[1—6].Themetabolic rate of bivalves is influenced by a number ofvariables,includingtemperature,body size,oxygen ten-sion,food concentration,reproductive state,activityleveland physiological condition.The excreted metabolites ofbivalves include ammonia,urea,uric acid and others,with ammonia comprising70%of the total excretion.Solenaia oleivorais a proper freshwater bivalve in China.For the consumer it has the follo... 相似文献