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101.
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
102.
MING-SHUN CHEN XIANG LIU YU-CHENG ZHU JOHN C. REESE GERALD E. W ILDE 《Insect Science》2006,13(5):339-348
A group of related genes has been isolated and characterized from the gut of Hessian fly larvae [Mayetiola destructor (Say)]. Members in this group appear to encode proteins with secretary signal peptides at the N-terminals. The mature putative proteins are small, acidic proteins with calculated molecular masses of 14.5 to 15.3 kDa, and isoelectric points from 4.56 to 4.88. Northern blot analysis revealed that these genes are expressed predominantly in the gut of Hessian fly larvae and pupae. Two related genes, GIOK1 and GIOK2, were isolated as tandem repeats. Both genes contain three exons and two introns. The intron/exon boundaries were conserved in terms of amino acid encoding, suggesting that they arose by gene duplication. The fact that the frequency of this group of clones in a gut cDNA library higher than that of total cDNA clones encoding digestive enzymes suggested that this group of proteins may perform an important function in the gut physiology of this insect. However, the exact functions of these proteins are as yet known since no sequence similarity could be identified between these proteins and any known sequences in public databases using standard methods. 相似文献
103.
Effects of cyhalothrin on the transient outward potassium current in central neurons of Helicoverpa armigera 总被引:1,自引:0,他引:1
YONG WANG BING-JUN HE QIANG ZHAO ZHI LIANG AN-XI LIU 《Insect Science》2006,13(1):13-17
The effects of cyhalothrin on the transient outward potassium current in central neurons of Helicoverpa armigera were studied by using the patch clamp techniques. The results showed that before using cyhalothrin (10.5 mmol/L), activation potential was approximately -40 mV, after application of the drug, the activation potential shifted roughly 10 mV to the negative potential direction, so channels can be activated more easily. Before and after cyhalothrin application, the change of current amplitude was insignificant. The value of V1/2 and k of activation curves did not change significantly, however, the V1/2 of the inactivation curves changed significantly. Inactivation curves significantly shifted to a negative direction, so that inactivation of the channels was hastened. It is indicated that there may exit a primary way in which cyhalothrin provides neurotoxicity to the nervous system through the regulation of activation potentials and inactivation state of IA channels. 相似文献
104.
NANNAN LIU QIANG XU LEE ZHANG 《Insect Science》2006,13(6):431-436
A mosquito strain of Aedes albopictus, HAmAal^G0, from Huntsville, Alabama, USA, showed a normal susceptibility and low tolerance to permethrin and resmethrin (pyrethroid insecticides) compared to a susceptible Ikaken strain, even though these pyrethroid insecticides have been used in the field for a long period of time in Alabama. Recently, we treated HAmAal^G0 in the laboratory with permethrin for five generations and detected no significant change in the level of resistance to permethrin in the selected mosquitoes, HAmAal^G0, compared with the parental strain HAmAal^G0. We then examined the allelic expression at the L-to-F kdr site of the sodium channel gene in the Aedes mosquitoes to address our hypothesis that the L-to-F kdr mutation was not present in HAmAal^G0 and HAmAal^G5 mosquitoes. We found that every tested individual in Ikaken, HAmAal^G5, and HAmAal^G5 populations expressed a codon of CTA at the L-to-F kdr site encoding Leu, strongly corresponding to their susceptibility to insecticides. 相似文献
105.
Relationship between osmotic stress and polyamines conjugated to the deoxyribonucleic acid-protein in wheat seedling roots 总被引:6,自引:0,他引:6
Polyamines (PAs) are biologically ubiquitous aliphatic amines that are implicated in many aspects of growth, development, sex differentiation, ripeness and senescence of plants[1―6]. It has been well documented that PAs are closely associated with plant … 相似文献
106.
SNP-为人类基因组描绘新的蓝图 总被引:26,自引:4,他引:22
几乎所有的慢性疾病都或多或少与遗传因素有关。在过去的二十年中,对人类遗传学的研究使人们认识到,理清各种疾病中遗传因素所起的作用将对诊断学、治疗学以及预防医学等各个领域带来革命。同时,了解遗传因素在疾病病因学中所占的地位也有利于人们对非遗传的环境因素对... 相似文献
107.
PCR-SSP分型检测上海汉族人群HLA-Cw位点血清学和非血清学鉴定的等位基因 总被引:9,自引:0,他引:9
应用补体介导的微量淋巴细胞毒实验可检出HLACw1~10,但有20%~50%的空白(blank)不能检出。利用PCRSSP对70例上海汉族样本进行HLACw等位基因分型,首次在中国汉族人群中检出Cw1201/1202、1203、1301、14、1601、1602、1701等非血清学鉴定的抗原,并对血清学鉴定抗原的基因进行分型,依次为Cw01、02、0302/0304、0303、04、0501、0602、0701/0702/0703及08。PCRSP分型使上海汉族人群HLACw位点空白基因频率从0.307下降到0.028。12例样本检出Cw08,与原来认为中国人群中Cw8罕见的观点不符。结果证明,PCRSSP用于HLACw基因分型是快速、准确的。 相似文献
108.
微核直径测试作为非整倍体诱发剂的分析手段 总被引:3,自引:0,他引:3
以小鼠骨髓红细胞微核直径测试,比较了秋水仙素(COL)与昆明山海棠(THH)、对苯二酚(HQ)在哺乳动物体细胞中的非整倍体诱发效应。丝裂霉素C(MMC)作为多功能染色体断裂剂引入实验,为诱发非整倍体的阴性对照。结果发现,COL组,71%的微核直径(d)大于或等于所在细胞直径(D)的五分之一(d≥D/5);THH诱发微核中,54%的微核d≥D/5;HQ及MMC组,分别有47%及14%的微核相对直径达此阈值。暗示THH及HQ具有类似COL的某种非整倍体诱发效应。微核直径测试可作为非整倍体诱发剂检测的辅助手段。
The relative diameters of micronucleus induced by colchicines(COL),Triptergium hypoglaucum(Level)Hutch(THH)and hydroquinone(HQ)were compared to evaluate their aneugenic activities in mouse bone marrow erythrocytes.MitomycinC(MMC)was taken as the negative control in the experiment because it is a multifunctional clastogen without aneugenic potential.Diameters of the cytoplasm(D)and the micronucleus(d)of each micronucleated erythrocytes were measured with a micrometer in a microscope.The frequency of relatively large micronuclei(d≥D/5)was found(71%) in COL treated group.In the THH and HQ treated groups,the relatively large micronuclei were 54% and 47%,respectively.Such micronuclei were infrequent(14%)in the MMC treated group.The results implied that THH and HQ may possess some aneugenic potential like COL. 相似文献
109.
魏丽珠 崔英霞 刘松君 耿建祥 徐建平WEI Li-Zhu CUI Ying-Xia LIU Song-Jun GENG Jian-Xiang XU Jian-Ping 《遗传》1993,15(4):8-9
对象、方法与结果 1989年4-12月,对南京市城区200对来院建卡的孕妇及其配偶,取外周血制备染色体,G显带分析,每例计数39个中期分裂相,分析3个核型.200对夫妇中发现6对夫妇之一方染色体异常(见表1).其余196对核型正常。对该6例的子女进了随访及染色体分析,结果见表1。 相似文献
110.
LIU Yi-xun 《基因组蛋白质组与生物信息学报(英文版)》1994,(2)
tPAInvolvementinOvulation──StudiesonMechanismofOvulation:RoleofTissueTypePlasminogenActivatorLIUYi-xun(StateKeyLaboratoryofRe... 相似文献