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81.
Results of this investigation indicate that the ferret (Mustela putorius) closely resembles the dog (Canis familiaris) and should be a useful research animal alternative. The tapetum lucidum is a common structure present in the eyes of dogs, cats (Felis catus) and other nocturnal animals. Our study showed that this structure was present in ferret eyes. The color or reflection of the ferret and dog tapetum was remarkably reduced by the general fixation with glutaraldehyde. However, this color fading phenomenon was not observed in the cat tapetum. These observations led to this comparative study on several morphological, histochemical and biochemical parameters on mature ferrets, dogs and cats including: (1) the number of center tapetum cell layers, (2) thickness of center tapetum, (3) presence of a microtubule-like structure in each tapetal rod, (4) presence of electron-dense cores in tapetal rods after prolonged fixation in glutaraldehyde, (5) retention of reflection or color of tapetum after prolonged glutaraldehyde fixation, (6) zygomatic bones of eye orbits, (7) zinc content in tapetum, (8) cysteine in the tapetum, (9) cysteine sulfinic acid decarboxylase in liver, (10) thickness of retina from center tapetum, (11) anterior view of skull configuration, and (12) lateral view of skull configuration (jaw and teeth). Among these 12 parameters, ferret and dog were similar in the first nine points; ferret and cat were similar to each other only in the last two points. There was no difference in retinal thickness among these three animals. 相似文献
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Lott Timothy J.; Yang Junghui; Ye Jianhong; Wallace Douglas C. 《Bioinformatics (Oxford, England)》1985,1(4):249-252
We have developed an inexpensive yet versatile microcomputer-basedsystem for quantitating light intensity levels in autoradiographs.This system employs a standard video camera interfaced to ananalog-to-digital convertor. A program has been written forthis system which can measure intensities within a defined regionof an autoradiograph, permitting an easy and accurate quantitationof spots or bands of irregular shape.
Received on June 18, 1985; accepted on September 3, 1985 相似文献
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本文用放射免疫测定法(RIA),测定了200~290例中国四川成都市郊30~73岁的正常成年男性血清睾酮(T)促黄体激素(LH).卵泡刺激素(FSH)及泌乳激素(PRL)的水平及其分布,进行了不同年龄水平差异显著性的观察,见到睾酮与泌乳激素水平无显著差异,促黄体激素及卵泡刺激素水平,随年龄之增加而升高,差异有显著性,并测得它们在血清中水平的分布:LH、FSH及PRL均为对数正态公布,T既非正态又非对数正态,但其频率分布较对称,接近正态分布。 相似文献
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Merritt Robert B. Kroon Wendy Hoffman Wienski Deborah A. Vincent Karen A. 《Biochemical genetics》1984,22(7-8):669-686
Genetic variation is described at 15 loci in 2 neotenic and 12 nonneotenic populations of red-spotted newts. Though high levels of genetic similarity (I=0.990) were found among all populations, allele frequencies at six of the eight most polymorphic loci show significant heterogeneity across populations. Change in allele frequencies at two of these loci (Pep-2 and Ldh-1) is significantly correlated with latitude. Interspecific homologies are established for newt peptidases based on substrate specificities and lactate dehydrogenases based on tissue distribution, thermal stability, and kinetic properties. Nonneotenic populations are highly variable (H=0.157) and neotenic populations are only slightly, but significantly, less variable (H=0.120). The high levels of heterozygosity detected in nonneotenic populations may result from large effective population size and/or environmental heterogeneity. The unexpectedly high heterozygosity values obtained for the neotenic populations may indicate adult dispersal or the presence of some previously undetected red efts at these localities. In any case, a major change in life history has apparently had little effect on the genetic structure of these populations.This research was supported by grants from the Blakeslee Fund of Smith College. 相似文献
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应用酶联免疫吸附试验检测马铃薯卷叶病毒 总被引:2,自引:0,他引:2
以辣根过氧化物酶标记马铃薯卷叶病毒抗体,采用双抗体夹心ELISA方法鉴定了马铃薯和洋酸浆的茎、叶、根及马铃薯块茎中的马铃薯卷叶病毒(Potato Leafroll Virus,PLRV),结果表明,对提纯的PLRV可测出的最低浓度为25ng/ml,当包被抗体浓度为40μg/ml、酶标记抗体稀释度为1/120时,可测出马铃薯茎、叶和根汁液中的PLRV,感染PLRV的洋酸浆茎、叶和根汁液的消光值,均比无病对照者高二倍以上,虽然感染PLRV的马铃薯休眠块茎维管束组织汁液的消光值高于无病毒对照,且脐部维管束组织消光值高于顶端,但测定打破休眠的感病块茎顶端维管束组织的阳性结果更为可靠和明显。 相似文献
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