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801.
Restricted maximum likelihood was used to estimate genetic parameters of male and female wing and thorax length in isofemale lines ofDrosophila melanogaster, and results compared to estimates obtained earlier with the classical analysis of variance approach. As parents within an isofemale line were unknown, a total of 500 parental pedigrees were simulated and mean estimates computed. Full and half sibs were distinguished, in contrast to usual isofemale studies in which animals were all treated as half sibs and hence heritability was overestimated. Heritability was thus estimated at 0.33, 0.38, 0.30 and 0.33 for male and female wing length and male and female thorax length, respectively, whereas corresponding estimates obtained using analysis of variance were 0.46, 0.54, 0.35 and 0.38. Genetic correlations between male and female traits were 0.85 and 0.62 for wing and thorax length, respectively. Sexual dimorphism and the ratio of female to male traits were moderately heritable (0.30 and 0.23 for wing length, 0.38 and 0.23 for thorax length). Both were moderately and positively correlated with female traits, and weakly and negatively correlated with male traits. Such heritabilities confirmed that sexual dimorphism might be a fast evolving trait inDrosophila. An erratum to this article is available at .  相似文献   
802.
本文演示了四焦点开关傅里叶域光学相干断层扫描系统用于全眼段成像和体内视轴参数(VAP)测量的可行性.使用包括不同厚度平行玻璃板的两个同步转盘来将探测光束的焦点位置从角膜以及晶状体的前部和后部切换到视网膜.该过程同时增加了参考光束的深度范围.这种多级聚焦的方法可以使探测光束完全聚焦在人眼的每个部分.初步实验表明,该方法可...  相似文献   
803.
无菌豚鼠与普通豚鼠血液学参数的比较   总被引:3,自引:0,他引:3  
目的对普通级豚鼠进行剖宫产,培育无菌豚鼠模型,并比较无菌豚鼠和普通级豚鼠的血液学参数。方法行子宫摘除术摘除子宫,在无菌隔离器中将子宫剥离取仔,用人工哺乳的方法将仔豚鼠培育成无菌豚鼠,并在固定的周期检测豚鼠的无菌情况。采用全血细胞计数分析仪、全自动血液生化分析仪测定无菌豚鼠、普通豚鼠的血常规和血生化参数。用SPSS12.0进行统计分析。结果无菌豚鼠和普通豚鼠在白细胞(WBC)、嗜碱性粒细胞数(BA#)、单核细胞百分比(MO)、血红蛋白浓度(MCHC)、中性粒细胞数(NE#)、嗜酸性粒细胞数(EO#)、淋巴细胞数(LY#)七个血常规指标上有差异显著性,其他指标没有显著性差异;谷丙转氨酶(ALT)、乳酸脱氢酶(LDH)、总蛋白(TP)、白蛋白(ALB)、葡萄糖(GLU)、总胆固醇(CHO)、总胆红素(TBIL)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、甘油三酯(TG)、球蛋白(GLO)、A/G、K、Na、谷酰转肽酶(GGT)15个指标上差异有显著性,其他指标差异无显著性。结论通过规范的子宫摘除术和人工喂养的方法获得符合标准的无菌豚鼠,与普通豚鼠在多项血液学指标上差异有显著性。  相似文献   
804.
Seven-day-old maize (Zea mays) plants were grown hydroponically for 10 days in S-deprived nutrient solution. The distribution profiles according to the position on the stem of the S-deprived laminas’ stomatal conductance, transpiration rate, photosynthetic rate, dry mass, water content, and specific surface area were monitored relative to control among others. Photochemical efficiency of photosystem II remained unaffected by the deprivation, as well as the specific surface area of all but the embryonic laminas after d2. In S-deficient plants, the embryonic (L0) and the uppermost lamina or the one below it presented mostly significant changes. The response ratios (Rr) of the L0 stomatal conductance oscillated; the oscillation started with an increase at d2. The corresponding Rr values of L0 transpiration and photosynthetic rates started oscillating at d4 in the same fashion. At d8, an increasing gradient appeared in water-content Rr values from L1 to the uppermost lamina. At d10, all but the embryonic laminas presented significantly reduced Rr values in water content. Changes in dry mass and surface area of laminas were synchronized. In control, the transpiration rate expressed per DM unit remained constant during the examined period, while under the deprivation it followed a power function of surface area.  相似文献   
805.
【目的】植绥螨是蓟马等害虫(螨)的重要捕食性天敌,在当前生物防治中应用广泛,本研究旨在为本地植绥螨资源的开发利用及筛选出控制西花蓟马Frankliniella occidentalis最有效的植绥螨天敌提供依据。【方法】以西花蓟马为猎物,在室内温度(25±1)℃、光照16L︰8D、相对湿度80%±5%的条件下,比较了内蒙古本地植绥螨种类有益真绥螨Euseius utilis Liang et Ke、苏氏副伦绥螨Paraseiulus soleiger Ribaga和巴氏新小绥螨Neoseiulus barkeri Hughes及目前应用的植绥螨斯氏钝绥螨Amblyseius swirskii Athias-Henriot、东方钝绥螨A.orientalis Ehara和黄瓜新小绥螨N.cucumeris Oudemans取食西花蓟马后的发育历期和生殖潜力,并组建了实验种群生命表以评价各类植绥螨的捕食潜能。【结果】有益真绥螨的日均产卵量(1.67±0.02)粒和黄瓜新小绥螨的日均产卵量(1.58±0.06)粒相近且无显著差异,仅次于斯氏钝绥螨(1.69±0.07)粒;有益真绥螨其子代雌雄性比与黄瓜新小绥螨的性比也相同(1.63︰1),低于斯氏钝绥螨(1.77︰1)和巴氏新小绥螨(1.64︰1);有益真绥螨的世代平均周期最短(T=19.36 d),内禀增长率(rm=0.16)和周限增长率(λ=1.17)均最大,种群倍增时间最短(t=4.33 d)。【结论】有益真绥螨以西花蓟马为食后种群数量增长的潜力强于其他5种植绥螨,是本地防治西花蓟马较有潜力的植绥螨种类。  相似文献   
806.
We have modeled an MTBP-MDM2–p53 regulatory network by integrating p53–MDM2 autoregulatory model (Proctor and Gray, 2008) with the effect of a cellular protein MTBP (MDM2 binding protein) which is allowed to bind with MDM2 (Brady et al., 2005). We study this model to investigate the activation of p53 and MDM2 steady state levels induced by MTBP protein under different stress conditions. Our simulation results in three approaches namely deterministic, Chemical Langevin equation and stochastic simulation of Master equation show a clear transition from damped limit cycle oscillation to fixed point oscillation during a certain time period with constant stress condition in the cell. This transition is the signature of transition of p53 and MDM2 levels from activated state to stabilized steady state levels. We present various phase diagrams to show the transition between unstable and stable states of p53 and MDM2 concentration levels and also their possible relations among critical value of the parameters at which the respective protein level reach stable steady states. In the stochastic approach, the dynamics of the proteins become noise induced process depending on the system size. We found that this noise enhances the stability of the p53 steady state level.  相似文献   
807.
Oreochromis niloticus, weighing 36.45 ± 1.12 g were exposed to 10%, 20% and 30% of the LC50 of CdCl2 which represents treatments (T1)1.68, (T2)3.36 and (T3)5.03 mg/l, respectively, for a period of 10, 20 and 30 days. It was found that, compared to a control group reading of 0.19 ± 0.03 μg/g dry weight, accumulation of Cd in the gills was significantly (p < 0.05) increased in samples ranging between 7.64 ± 0.86 and 61.73 ± 0.82 μg/g dry weight from T1 at 10 days to T3 at 30 days. The accumulation of Cd in the liver, meanwhile, was also observed to significantly increase (p < 0.05) with increasing time and concentrations with results ranging between 3.21 ± 0.12 and 181.61 ± 1.32 compared to the control group results of 0.29 ± 0.04 μg/g dry weight. Although muscles exhibited lower levels of accumulation than the gills and liver they still showed the same pattern of increase compared to the control group, with a significant difference ranging between 0.32 ± 0.02 and 2.16 ± 0.08 compared to the control group results of 0.03 ± 0.001 μg/g dry weight. Also, haematological parameters such as red blood cells (RBCs), haemoglobin (Hb) and haematocrit (Hct) were reduced in fish exposed to Cd at all periods, with significant differences (p < 0.05). Plasma glucose concentration showed a significant increase. Total protein levels of fish showed a significant reduction (p > 0.05) for all exposed treatments. Also, the total lipid level increased significantly as fish were exposed to increasing cadmium concentrations, compared to control fish. Finally, the activities of aspartate aminotransferase (AST IU/l) and alanine aminotransferase (ALT IU/l) showed a significant increase (p < 0.05) with increasing time and concentrations.  相似文献   
808.
皖南花猪11种血液生化指标的发育性变化及性别差异   总被引:2,自引:0,他引:2  
随机选择出生30、45、90、180日龄的皖南花猪公母各5头,测定了11项血清生化指标.结果显示:血糖(GLU)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、游离脂肪酸(FFA)、脂联素(ADP)、瘦素(leptin)和IgG有极显著的发育性变化(P0.01);而甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、IgA和IgM等没有明显的发育性变化.母猪的TG、TC、HDL-C和IgM极显著或显著大于公猪(P0.01或P0.05),其他血清生化指标虽在总体上没有性别差异,但在有些日龄差异明显,大多表现为母猪在90或180日龄大于公猪.结果表明:皖南花猪血液生化指标有特定的发育性模式,并存在不同程度的性别差异.  相似文献   
809.
铅对小鼠血液和肝肾影响的实验性初步观察   总被引:3,自引:0,他引:3  
赵剑  童希琼  蔡亚非 《生物学杂志》2010,27(1):17-19,38
用全血细胞分析仪检测染毒小鼠新鲜血样,再用日立7020生化分析仪,配合试剂盒法对血清进行检测,研究铅对血液与肝肾功能的影响,结果表明:100mg/kg浓度的醋酸铅对小鼠的血液有显著影响,白细胞数目(WBC),淋巴细胞数目(Lymph),中性粒细胞数目(Gran)等指标显著增加(P〈0.05),此外对血小板凝血系统功能显著影响,血小板数目(PLT)等指标下降极显著(P〈0.01),对血红细胞(RBC),血红蛋白(HGB)等指标影响不显著(P〉0.05)。肝肾功能性指标:谷丙转氨酶(AIJT),谷草转氨酶(AST)尿素氮(UREA)肌酐(CREA)生化酶显著偏离正常值(P〈0.05)。表明铅对肝脏肾脏功能有显著的破坏。对检测结果做了进一步的分析讨论。  相似文献   
810.
目的了解刺猬的血液生理生化参数正常值及其季节性差异。方法采用BC-3000 Plus全自动血液细胞分析仪和BAYER-ADVIA-1650全自动生化分析仪,分别对刺猬的13项生理指标和15项生化指标进行了测定,并比较分析了春季、夏季和秋季的血液生理生化指标。结果刺猬雌体和雄体的平均红细胞体积(MCV)在夏季均显著小于秋季,雄体夏季的平均红细胞血红蛋白(MCH)小于秋季,说明刺猬秋季的血液载氧能力高于夏季。白细胞数目(WBC)没有季节和性别的显著差异,说明刺猬在三个季节的免疫能力差别不大。在血液生化指标中,刺猬(雌雄)春季和秋季的葡萄糖(GLU)含量均显著高于夏季;雌性刺猬春季的谷草转氨酶(AST)显著大于夏季和秋季;雄性刺猬的总胆固醇(CHOL)和低密度脂蛋白(LDLC)均表现为秋季的显著高于春季和夏季的。结论生理生化指标的不同反映了刺猬在活动能力、代谢水平、营养状况、健康状况等方面存在性别和季节性差异。  相似文献   
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