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1.
An unconfirmed study by Fang (Ph.D. thesis, Univ. of London, 1950) in Britain showed that individuals with Down syndrome had lower total a-b ridge counts in palmar Interdigital area II (ID II) than a group of controls. This study compares 603 white Down syndrome cases and 93 black Down syndrome cases with 668 white and 402 black controls. Our results confirm those of Fang in that the Down syndrome cases in both racial groups had lower total a-b ridge counts than their respective controls. In addition, the black controls and Down syndrome cases had lower a-b ridge counts than their white counterparts. The mean a-b ridge count was significantly lower in individuals with a pattern in ID II compared to individuals without a pattern in ID II in both the Down syndrome and control groups. Some of the lower a-b ridge counts in the Down syndrome samples can be accounted for by the fact that there is an increased frequency of a pattern in ID II in Down syndrome cases. Both Down syndrome and normal individuals who had a pattern unilaterally had a lower than expected a-b ridge count on the contralateral hand that did not have a pattern. There was a tendency also for increased asymmetry in Down syndrome cases with a pattern in ID II.  相似文献   

2.
In order to test the hypothesis of a major gene effect on absolute total finger ridge count (ATFRC), the nature of relationship between mean ATFRC and its variability was evaluated in a series of 47 population samples from India. Regression analysis showed that both the standard deviation and the coefficient of variation are significantly related to mean ATFRC, and about 35% of the variation in ATFRC is explained by the dependent variable coefficent of variation. These results support the hypothesis of a major gene effect on the trait ATFRC.  相似文献   

3.
A population sample from the Milne Bay district of Papua-New Guinea was found to have extremely high pattern intensity indices and total ridge-counts. These fell into the range of certain Australian Aboriginal tribes, and so argue for a possible connection between this region of Melanesia and the Australian Aborigines, although equally strong connections with other regions of Melanesia are known.  相似文献   

4.
The North Pennine Dales are sparsely populated and deeply indented valleys in the central uplands of northern England. Travel to service centres on the surrounding low lying terrain, especially to the industrial conurbations, is channelled by way of the dale mouths. Communication over the dale heads is difficult and is thus much dictated by topography and by the orientation of each dale. This paper represents the first of two reports on the finger and palmar dermatoglyphics of the populations. Basic data are presented on sex differences, bilateral asymmetry and digital diversity. Univariate statistical tests have been carried out between the dales' populations for several stages based on the selection of individuals by ancestry. Several significant differences occur but no more than would be expected by chance. Distinct spatial patterning does recur for several variables, but on the available data a univariate approach has been unsuccessful in determining the nature and causes of overall population interrelationships.  相似文献   

5.
Dermatoglyphics of schizophrenics, patients with Down's syndrome and mentally retarded males were compared with those of normal Australian Europeans. A computer programme of multivariate analysis of fifteen dermatoglyphic features was utilized. This analysis produces two significant variates of each of the populations plotted in two-dimensional space. The distance, measured in arbitrary units, between any two populations was studied for its significance. It was noticed that the patients with Down's syndrome separated significantly from the rest of the groups. The importance of multivariate analysis in the study of dermatoglyphics in comparing two or more populations is discussed.  相似文献   

6.
The paper deals with the bilateral palmar prints of 3000 males belonging to 20 Dhangar castes of Maharashtra which were analysed (1) to compare the pattern of variation of palmar triradii with respect to other traits, (2) to examine the degree of similarity between clusters based on dermatoglyphics anthropometry and genetic markers and (3) relating these similarities with their ethnographic and geographic proximities. The results of this study confirm the general presumptions, (a) that dermal traits, in general, and palmar characters, in particular, do help in understanding the biologic/ethnic affinities among different groups both at macro and micro levels and (b) the different types of traits, which are likely to be influenced by different genetic and/or environmental factors give rise to different clustering patterns.  相似文献   

7.
Twenty components extracted from the essential oil in the leaves of 172 samples of Perilla frutescens var. crispa (vegetable crop form), P. frutescens var. frutescens (oil crop form), the wild/weedy form of P. frutescens, and three wild Perilla species, Perilla citriodora, Perilla hirtella and Perilla setoyensis were analyzed using GC/MS. A wide range of essential oil components were found among the wild/weedy form of P. frutescens, whereas distinctive components were detected in each wild Perilla species. Egomaketone, asaron, methyleugenol and 4,6-dimethoxy- or 4,7-dimethoxy-5-(2-propenyl)-1,3-dioxaindan were detected from Perilla for the first time. Limonene derivatives, piperitone and piperitenone, were detected from P. citriodora. Discovery of the limonene derivatives in this Perilla species provides evidence of this wild species being a genome donor of P. frutescens, while limonene synthase has been considered to be a specific enzyme in cultivated P. frutescens. These results will be useful for the evaluation and utilization of Perilla genetic resources.  相似文献   

8.
The cytoplasmic dot hybridization method was improved by eliminating non-specific false signals. The non-specific binding to a probe disappeared almost completely when the hybridized nitrocellulose sheet was treated with pronase. Using this improved method we demonstrated that reagents such as 12-O-tetradecanoylphorbol-13-acetate (TPA), concanavalin A (Con A) and a calcium ionophore (A23187) could induce the expression of IFN-gamma gene of a human T-lymphoblastoid cell line, TCL-Fuj 2M, where TPA functioned synergistically with Con A and A23187. However, when the cells were cultured with the ionophore for more than one day the amount of IFN-gamma mRNA was markedly reduced to a low level.  相似文献   

9.
10.
Measurements in populations which serve as valid indicators of biological relationship should be proportional to genetic distance. In order to test the utility of discrete cranial traits for estimating genetic distances among populations, estimates of admixture are obtained for gene frequency data and nonmetric cranial data in São Paulo mulattos (M). The gene frequency data serve as a control that the three populations are related as stated: estimates of admixture are obtained by using São Paulo whites (W) and blacks (B) as parental populations and by estimating the parameter of admixture, m, in the model pM = (1 ? m) pW + mpB (Elston, 1971) where the p's are either gene frequencies or nonmetric trait frequencies. A test of goodness of fit of the model provides a means of ascertaining whether or not the data fit this linear model. While the gene frequency data indicate distances among the three populations which are highly compatible with the linear model of admixture, the nonmetric data show significant deviations from the model. This implies that the frequencies of the nonmetric traits in the populations used in this analysis are not a linear function of genetic distance. This discourages the use of nonmetric traits in making quantitative conclusions about genetic relationships. It also suggests the need for investigation of the use of other skeletal characters for estimating genetic distance, as well as approaches for such investigations through the study of hybrid individuals.  相似文献   

11.
Pack C  Saito K  Tamura M  Kinjo M 《Biophysical journal》2006,91(10):3921-3936
Four different tandem EGFPs were constructed to elucidate the nuclear microenvironment by quantifying its diffusional properties in both aqueous solution and the nuclei of living cells. Diffusion of tandem EGFP was dependent on the length of the protein as a rod-like molecule or molecular ruler in solution. On the other hand, we found two kinds of mobility, fast diffusional mobility and much slower diffusional mobility depending on cellular compartments in living cells. Diffusion in the cytoplasm and the nucleoplasm was mainly measured as fast diffusional mobility. In contrast, diffusion in the nucleolus was complex and mainly much slower diffusional mobility, although both the fast and the slow diffusional mobilities were dependent on the protein length. Interestingly, we found that diffusion in the nucleolus was clearly changed by energy depletion, even though the diffusion in the cytoplasm and the nucleoplasm was not changed. Our results suggest that the nucleolar microenvironment is sensitive to energy depletion and very different from the nucleoplasm.  相似文献   

12.
Summary The secondary and tertiary structural features of botulinum neurotoxin (NT) serotype A, a dichain protein (Mr 145 000), and its two subunits, the heavy (H) and light (L) chains (Mr 97 000 and 53 000, respectively) were examined using circular dichroism and fluorescence spectorscopy. Nearly 70% of the amino acid residues in each of the three polypeptide preparations were found in ordered structure (sum of helix, sheet and turns). Also, the helix, sheet, turns and random coil contents of the dichain NT were nearly equal to the weighted mean of each of these secondary structure parameters of the L and H chains; e.g., sum of helix of L chain (22%) and H chain (18.7%), as weighted mean, 19.8% was similar to that of NT (20%). These agreements suggested that the secondary structures of the subunits of the dichain NT do not significantly change when they are separated as isolated L and H chains. Fluorescence emission maximum of L chain, 4 nm less (blue shift) than that of H chain, suggested relatively more hydrophobic environment of fluorescent tryptophan residue(s) of L chain. Tryptophan fluorescence quantum yields of L chain, H chain and the NT, 0.072, 0.174 and 0.197, respectively, suggested that a) an alteration in the micro-environment of the tryptophan residues was possibly caused by interactions of L and H chain subunits of the NT and b) quantum yields for L and H chains were altered when they are together as subunits of the NT. Possible implications of structural features of the L and H chains, their interactions and the molecular mechanism of action of botulinum NT are assessed.  相似文献   

13.
14.
Ackers D  Buchen B  Hejnowicz Z  Sievers A 《Planta》2000,211(1):133-143
 The spatial pattern of acropetal and basipetal cytoplasmic streaming velocities has been studied by laser-Doppler-velocimetry (LDV) in the positively gravitropic (downward growing) rhizoids of Chara globularis Thuill. and for the first time in the negatively gravitropic (upward growing) protonemata. The LDV method proved to be precise and yielded reproducible results even when tiny differences in velocities were measured. In the apical parts of the streaming regions of both cell types, acropetal streaming was faster than basipetal streaming. Starting at the apical reversal point of streaming, the velocity increased basipetally with the distance from that point and became fairly constant close to the basal reversal point; subsequently, the velocity decreased slightly acropetally as the apical reversal point was again approached. There was no change in velocity at the basal reversal point. However, at the apical reversal point there was an abrupt decrease in velocity. The pattern of the ratio of acropetal to basipetal streaming velocity (VR) was a function of the relative distance of the site of measurement from the apical reversal point rather than a function of the absolute distance. Upon inversion of the rhizoids, the VR decreased on average by 3.8% (±0.4%), indicating that the effect of gravity on the streaming velocity was merely physical and without a physiological amplification. Rhizoids that had developed on the slowly rotating horizontal axis of a clinostat, and had never experienced a constant gravity vector, were similar to normally grown rhizoids with respect to VR pattern. In protonemata, the VR pattern was not significantly different from that in rhizoids although the direction of growth was inverse. In rhizoids, oryzalin caused the polar organization of the cell to disappear and nullified the differences in streaming velocities, and cytochalasin D decreased the velocity of basipetal streaming slightly more than that of acropetal streaming. Cyclopiazonic acid, known as an inhibitor of the Ca2+-ATPase of the endoplasmic reticulum, also reduced the streaming velocities in rhizoids, but had slightly more effect on the acropetal stream. It is possible that the endogenous difference in streaming velocities in both rhizoids and protonemata is caused by differences in the cytoskeletal organization of the opposing streams and/or loading of inhibitors (like Ca2+) from the apical/subapical zone into the basipetally streaming endoplasm. Received: 4 October 1999 / Accepted: 4 November 1999  相似文献   

15.
16.
Ferritin maintains iron in a bioavailable, nontoxic form for vertebrates and invertebrates, higher plants, fungi, and bacteria; the protein is formed from two classes of subunits (H and L) in ratios which vary in different cell types. Ferritin may be an abundant, differentiation-specific protein or a "housekeeping" protein. The red cells of embryos are specialized for iron storage and have abundant ferritin; iron regulates the synthesis of ferritin in such cells translationally by recruitment of stored, ferritin mRNA and by translational competition. To characterize mRNA regulated in such a manner, we prepared cDNA from reticulocytes of bullfrog tadpoles, a readily available source of embryonic red cells; moreover, no protein sequence information was available for nonmammalian ferritin. An almost full-length (817 base pairs) cDNA (pJD5F12) was isolated and sequenced, the 5' end was analyzed by primer extension, and the cloned DNA was used as a hybridization probe. We have shown that ferritin mRNA is stored in the cytoplasm and that the 5' end of the mRNA is heterogeneous. The 5'-untranslated region of ferritin mRNA consisted of 143 nucleotides in the major (65%) species and 146 or 152 in the minor species (approximately 17% each). (Heterogeneity is characteristic of some other abundant mRNAs, e.g. globin, which is also translationally regulated.) Since excess iron had no detectable effect on the heterogeneity of the 5' end of ferritin mRNA, the feature is more likely associated with mRNA abundance and/or cell specialization than translational control. In the bullfrog, as in humans and rats, ferritin is encoded by multiple genomic sequences (four to eight) which specify proteins of considerable homology. For example, 75 of the 81 amino acids present in all mammalian ferritins sequenced are also present in the frog; the overall homology between frogs and humans or rats is 59-66%. Ferritin H and L subunits in humans are distinct (overall homology 56%) and appear to have diverged from a common precursor relatively recently. In contrast, ferritin H and L subunits have high homology in tadpole red cells, determined by hybrid select translation, which suggests that bullfrog red cell ferritin may be close to the primordial sequence.  相似文献   

17.
《Palaeoworld》2016,25(2):149-169
The order Osmundales is a unique fern taxon with extensive fossil records in geological past. Diverse osmundalean fossils have been reported from China, ranging in age from the Late Palaeozoic to the Cenozoic. Most of them are based on leaf impressions/compressions, but permineralized rhizomes are also well documented. In this study, we provide a systematic overview on fossil osmundalean ferns in China with special references on diversity variations, distribution patterns, and evolutionary implications. Fossil evidence indicates that this fern lineage first appeared in the Late Palaeozoic in China. The Late Triassic to Middle Jurassic interval was the radiation stage. From the Late Jurassic onward, fossil diversity declined rapidly. Cenozoic osmundalean taxa are represented by the relict species of Osmunda. Geographically, osmundalean fossils are found from both the Northern and Southern phytoprovinces of China, though variations are documented for geographical ranges. The Chinese fossil records cover almost all important stages for the macroevolution of the Osmundales, and contribute to further understanding of evolutionary processes of this peculiar fern lineage.  相似文献   

18.
以贵州省玉米 油菜轮作田和大豆 冬小麦轮作田为N2 O释放通量测量对象 ,根据DNDC模型能较好地拟合田间N2 O释放通量季节变化及施肥和翻耕对释放的影响 ,采用DNDC模型定量探讨了上述作物生长季节有机肥施用量、N肥施用量及施肥日期、N肥类型和施肥深度、翻耕深度和翻耕日期等变化对亚热带旱田生态系统N2 O释放的潜在影响 .为今后通过改变施肥和耕作方式来控制农业土壤N2 O释放量提供研究基础和参考 .  相似文献   

19.
Summary Type 4 stability has been proposed to measure a cultivar's homeostatic property to resist unpredictable environmental variation. The requirement for calculating this stability is that the experiment must contain a time factor in addition to the cultivar x location factors. Of the two time factors, year and seeding-time, the latter is less attractive biologically because it represents only a part of the broader context of unpredictable variation represented by years, but it is attractive in terms of shortening the test period. Investigation of historical data from the Eastern Cooperative trials and the Ontario Production trials in Canada indicates that the unpredictable variation generated by seeding-time was about half that generated by year. Although type 4 stability measured by both factors appears to be the same, the stability measured by seeding-time is more prone to variation. The implication is that complete substitution of the year factor by seeding-time is not appropriate, but use of both factors in combination may be sensible.Contribution No. C-055 from the Engineering and Statistical Research Centre, Research Branch, Agriculture Canada, Ottawa, K1A 0C6, Canada  相似文献   

20.
The colour pattern of the Gran Canarian skink is described with eight independent colour pattern characters. Significant geographic variation occurs in each character. There are generally high levels of congruence between the patterns of geographic variation in each character although some differences exist. In canonical variate analyses, the first canonical variate expresses most of the among-locality variation in colour pattern, indicating a largely unidimensional pattern. Patterns of geographic variation in the colour pattern are portrayed by contouring. This reveals north-east/south-west clines for seven of the individual characters and the generalized pattern (CV1). Four causal hypotheses were erected which predicted four different unidimensional patterns of geographic variation. Mantel tests and partial correlation analyses were used to compare the observed patterns of microgeographic variation with the four hypothesized patterns. This method suggests differential selection occurring between ecotones as the cause of the microgeographic variation. Microgeographic variation in some aspects of the colour pattern can be explained by selection for different anti-predator strategies in the hot, arid southern areas vs the cooler, lusher northern areas.  相似文献   

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