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1.
B. Karmakar  K. Yakovenko  E. Kobyliansky   《HOMO》2003,53(3):263-278
Five different endogamous populations who encompass the main social rank in the caste hierarchy of West Bengal were analysed for this report. The present approach is to compare the pattern of sex differences/similarities exhibited by two different sets of dermatoglyphic traits. Cluster and discriminant analysis and Mantel test of matrix correlations were performed. The nature of variation between sexes within population groups and two types of variable sets has a good similarity in all five populations. These results strongly suggest that the two categories of dermatoglyphic variables provide similar possibilities to discriminate between the sexes in populations.  相似文献   

2.
Summary

The Author observing the great disagreement of the terminology usually adopted for the apomictic phenomena, examines the whole series of the phenomena noted both in regards of the formation of the gametophyte and of the embryo. The forming of the gametophyte is fixed on the base of nature of its original cell, normally a haploid spore or »haplospore« (phenomenon of the »haplospory« following the regular meiosis), rarely a diploid spore or »diplospore« (phenomenon of the »diplospory« following the irregular meiosis, as for instance in the case of restitution nucleus, etc.). The original cell can be at least represented by the same cell that usually is the spore mother cell, whether for the outward causes, or for inward causes is lacking the usual reductional process. For the failure of the meiotic process, such a cell cannot be called »spore«.

A cell of the somatic tissue of the sporophyte can even become the original cell of the gametophyte always in case of the absence of the meiosis. These two last cases of apospory are respectively called: »somatic apospory« and »gonial apospory« (= germinal apospory) (Chiarugi 1926).

The formation of the embryo is fixed on the base of the nature of the fecundation. The principal phenomena of the fecundation are represented by the following cases: »amphigamy« (or eugamy, or gamy), »semigamy, »pseudogamy«, »apogamy« »parthenogenesis«. The A. uses the term »apogamy« both for the diploid eggs and for the haploid eggs in which the stimulation of the division is produced by the pollen-tube or by male nuclei, in absence of the gamy.

The term »parthenogenesis« is restricted to the division of the haploid or diploid eggs in which the stimulation is not caused by pollen-tube nor even for the great reason, by the male nuclei existing in it.  相似文献   

3.
Being based solely on neontological data, all «unique parent» evolutionary hypotheses, of which «Mitochondrial Eve» is one, fall into the category ofscala naturae. Mathematical treatment of neontological data bases, using cladistic approaches does not confer the status of scientific hypotheses onto such scenarios. Apart from these fundamental problems, such hypotheses are flawed on a number of other bases, including the fact that there is a proportion of parental contribution to mitochondrial lineages, despite widely publicised statements that mithocondrial DNA in mammals is «strictly» maternally inherited. Other weaknesses of «unique mother» hypotheses on that their proponents endeavour to describe the evolution of diploid organisms on the basis of variability in extant haploid organelles, the evolution of which is delinked from that of the diploid organism. A further difficulty is that it is not possible to reconstruct interspecific relationships on the basis of intraspecific variability. There is a general ignorance among proponents of «unique mother» hypotheses regarding the distribution of biological variability on the surface of the globe, a fact which renders the molecular clock inaccurate, and which upsets the simplistic proposal that molecular diversity equates with time. «Unique mother» scenarios are also invalidated by the presence of shared chromosome and other polymorphisms in african great apes and humans at similar percentages in the different lineages, a fact which indicates that these evolving populations did not experience «bottlenecks». These and other difficulties effectively refute the «Mitochondrial Eve» hypothesis, which in any case much resembles creationism of a special kind, in which the offspring of a breeding pair are visualised as belonging to a species different from its parents. Such extreme examples of the punctuational mode of evolution are highly likely to be incorrect.  相似文献   

4.
IntroductionTo investigate the relationship between self-rated health and mortality at 5 years of follow-up among the elderly in a rural community.DesignSurvival study with a 5-year follow-up.ParticipantsRepresentative sample of 408 individuals aged more than 65 years living in a rural municipality in the north-west of Spain.ResultsSurvival was significantly lower among individuals who reported «poor» or «very poor» health (relative risk [RR] = 1.56; 95% confidence interval [95% CI], 1.04-2.33). However, after adjusting for other variables (age, sex, education, severe disease, toxic habits, and mobility) the probability of survival among these individuals reporting «poor» or «very poor» health was similar to that among participants who rated their health as «average», «good » or «very good» (RR = 1.15; 95% CI, 0.71-1.87). In the multivariate analysis, only age, regular smoking, and mobility remained as significant predictive factors of mortality.ConclusionsAfter adjusting for demographic and socioeconomic factors and for objective health status, self-rated health does not have a direct effect on mortality. The degree of mobility does seem to be useful in predicting mortality.  相似文献   

5.
Summary

The Authors describe in Sambucus nigra L the occurrence of the » apohomeotypic teiosis « followed by a »mitosis with diplounivalents « (Battaglia 1945, 1947) in ae somatic tissue of the style. The AA. observed also the occasional formation f four haploid nuclei and then the occurence of the »eumeiosis« (Battaglia 1945).  相似文献   

6.
Abstract

Embryology of « Leontopodium nivale » (Ten.) Huet ex Hand.-Mazz. — As in « Leontopodium alpinum » Cass. var. a typicum Fiori e Paoletti, from different alpine localities, no cases of apomixis have been observed (Maugini 1962) while Sokolowska-Kulczycka (1959) has noticed this phenomenon in the same species collected on the Tatra mountains, an embryological research on « Leontopodium nivale » (Ten.) Huet ex Hand. Mazz. has been undertaken. The material, collected in the alpine garden of Campo Imperatore (Abruzzo), has shown that the development of the female gametophyte occurs as in Leontopodium alpinum, according to the normal monomegasporial type which leads to the formation of an 8-nucleate gametophyte which at maturity is almost always poliantipodate. In « Leontopodium nivale » there is no trace of apomixix, but many cases of degeneration, particularly in the mature gametophyte, have been observed.  相似文献   

7.
Canine inflammatory mammary cancer (IMC) shares epidemiologic, histopathological and clinical characteristics with the disease in humans and has been proposed as a natural model for human inflammatory breast cancer (IBC). The aim of this study was to characterize a new cell line from IMC (IPC-366) for the comparative study of both IMC and IBC. Tumors cells from a female dog with clinical IMC were collected. The cells were grown under adherent conditions. The growth, cytological, ultrastructural and immunohistochemical (IHC) characteristics of IPC-366 were evaluated. Ten female Balb/SCID mice were inoculated with IPC-366 cells to assess their tumorigenicity and metastatic potential. Chromosome aberration test and Karyotype revealed the presence of structural aberration, numerical and neutral rearrangements, demonstrating a chromosomal instability. Microscopic examination of tumor revealed an epithelial morphology with marked anysocytosis. Cytological and histological examination of smears and ultrathin sections by electron microscopy revealed that IPC-366 is formed by highly malignant large round or polygonal cells characterized by marked atypia and prominent nucleoli and frequent multinucleated cells. Some cells had cytoplasmic empty spaces covered by cytoplasmic membrane resembling capillary endothelial cells, a phenomenon that has been related to s vasculogenic mimicry. IHC characterization of IPC-366 was basal-like: epithelial cells (AE1/AE3+, CK14+, vimentin+, actin-, p63-, ER-, PR-, HER-2, E-cadherin, overexpressed COX-2 and high Ki-67 proliferation index (87.15 %). At 2 weeks after inoculating the IPC-366 cells, a tumor mass was found in 100 % of mice. At 4 weeks metastases in lung and lymph nodes were found. Xenograph tumors maintained the original IHC characteristics of the female dog tumor. In summary, the cell line IPC-366 is a fast growing malignant triple negative cell line model of inflammatory mammary carcinoma that can be used for the comparative study of both IMC and IBC.  相似文献   

8.
Sociobiological explanation of altruism, through theories as such «kin selection», cannot reach the wealth of human morality; it is necessary to add some specific traits in order to explain the human way to ultrasociability. Some of them appear within the classical school of «moral sense», distinguishing between two different levels («motive to act» and «moral criterion») of moral phenomenon. Due to the complexity of criterion level, here we deal with a broad model of human moral phenomenon, proposing three different dominions («motive to act», «personal criterion», «collective values»), and trying to find possible phylogenetic roots of them through a cognitive approach.  相似文献   

9.
Five hundred families from five different endogamous populations encompassing the main social rank in the caste hierarchy of the same geographical area of West Bengal, India, were analyzed to present variation in qualitative pattern types on fingers and palms. Sex dimorphism, homogeneous in all populations, suggests common characteristics of dermatoglyphic patterns. The pattern types are not uniformly distributed on 10 fingers and palmar configurational areas. However, most of these observations are homogeneous in nature, in both sexes among 5 populations. But the two sets of results on fingers and palms are not exactly the same. Palmar dermatoglyphic relationship reflects the better caste affinities, perhaps due to embryological development, having relatively a longer growth period compared to fingers (Cummins 1929). The present findings indicate that the qualitative dermatoglyphic affinities conform to the known ethnohistorical background of these populations, which correspond also to the results of quantitative dermatoglyphics as well as serological and biochemical markers of these populations. These observations indicate that these population groups have a common genetic background and thus traditional grouping of Indian populations on the basis of caste hierarchy may not be a reflection of the genetic origin of the population. In dermatoglyphic affinities, both qualitative and quantitative traits therefore may be quite useful in tracing the ethnohistorical background of these populations.  相似文献   

10.
Abstract

Photosynthetic rates of some algae in the marine cave « Grotta delle Viole » (Is. S. Domino - Tremiti). — The « Grotta delle Viole » is one of the several marine caves located along the calcareous rocky southern littoral of the Island S. Domino (Tremiti) in the Adriatic Sea. Morphologically this cave is a tunnel, which connects the open littoral sea with a little bay. Availing of these environmental factors, we have chosen three stations to measure the photosyn-thetic yield, under completely natural conditions, of algae particularly important for some marine communities, described in an other paper (see, Pignatti S. et al. 1967). In station 1 (fig. 1) we have a biotope with strongly reduced light and in the neighbouring stations 2 and 3, two biotopes exposed to sun-light. We have studied three species living in dark places (« Peyssonelia » cfr. « harveyana », « Palmophyllum crassum » and « Pseudolithophyllum expansum » two of well lighted habitas (« Padina pavonia » and « Dictyota dichotoma » and one of intermediate place (« Codium difforme ») Some information on the optical conditions of the seawater have been obtained with a photoelectric cell, filters were used to measure the red and blue light penetration (Tab. 1, 2). This part of the Adriatic Sea is characterized by high penetration of blue light. In the cave this light is highly predominant. The photosynthetic rates were measured in natural conditions by determining the output in time O2 using the Winkler method (Tab. 3) and the CO2 changes by measuring pH-changes in short time intervals with an original method using a submarine incubation cell, of our design, equipped with the electrodes of a pH-meter and a spot-light galvanometer as measure instrument. The data obtained with the latter method have been statistically analized, their significance discussed and reported in Tab. 4. On the basis of the results, the species, which are confined in places with reduced light intensity, show a low but measurable photosynthetic surplus only in their natural habitats, transferred in high-light intensity they show a deficit. This fact can suggest the hypotheses: deactivation of the chlorophyll in green and blue light or competitive inhibition due to the presence of accessory pigments. The species of sunny habitats transferred in low-light intensity show an assimilatory deficit, that in this case, with great probability, is due to the progressive reduction of the photosynthetic process. These considerations explaine also the observed distributions of the species and of the algal communities (fig. 1), since each of them is connected with a light optimum. It seems important moreover to note that here, for the first time, data are given also on photosynthetic activity of Lithothamnia.  相似文献   

11.
Abstract

C14O2 fixation in plant tissues « in vitro ». — In the present work it has been examinated the autotrophic and heterotrophic CO2 fixation of explants of « Helianthus tuberosus » « in vitro » and the photosyntetic efficiency of leaves produced from buds of « in vitro » explants of « Cichorium intybus » compared with that of mature leaves from normal plants of the same species. From our results it is evident that « in vitro » explants of « Helianthus tuberosus », grown, in the light, are able to autotrophically incorporate C14O2; the distribution of the radioactivity into the various fractions shows a large influence of the light on the neutral fraction containing sugars (50% of the total radioactivity). In the chlorophyllous explants the dark CO2 fixation is obviously of heterotrophic type: 97% of the total radioactivity is incorporated in amine acids (43%) and the organic acids (53%); on the other hand in the dark grown explants the radioactivity is differently distributed between amino acids (59%) and organic acids (39%). Mature leaves from normal plants and leaves produced from buds of « in vitro » explants of « Cichorium intybus » incorporate the same quantity of C14O2 when expressed per mg of chlorophyll; the different distribution of the radioactivity in the neutral and acid fractions could be explained in terms of a different utilization pathway of the photosynthates in the two tissues.  相似文献   

12.
13 dermatoglyphic variables have been studied in eight population samples (five smaller isolated and three larger populations) to identify the possible differences between the larger and the smaller isolated populations. The data and neighbor joining trees for the dermatoglyphic variables show distinct differences between males and females. The isolated population of the Lutheran Mountains is clearly separated from the other populations. Combining the results of dermatoglyphic and 12 hemogenetic variables (only for six populations) the male and female trees are nearly identical. The three isolated populations are clearly separated, whereas the larger ones show smaller distances.  相似文献   

13.
Abstract

On the presence of « hyphycellariola » (swollen celles) and conidia in three lichenized fungi cultivated « in vitro ». — The Authors refer to the presence of « cellariola » (and « hyphycellariola ») found in pure cultures « in vitro » of the mycobiont of Xanthoria parietina and describe the morphology of conidia in the fungus isolated from Sarcogyne similis and Acarospora fuscata.

As far as the « cellariola » and « hyphycellariola » are concerned, it is the first note relative to the mycobionts of Lichens.

The Authors report the data of the utilized medium and the morphological observations.

This previous studies will be intensified by further research.  相似文献   

14.
C. Chiland 《Andrologie》2000,10(1):66-74
Transsexualism is a phenomenon of our culture. In the past, there were men and women who could not accept their innate sex. What is new is linked to our modern medical technology which offers patients a so-called «change of sex» using hormones and surgery; in fact it is a change in appearance, allowing the individual to «pass» as a member of the other sex. Some societies had and still have a social status for a third gender, but our transsexuals do not want to be treated as members of a third gender, they want to belong to the other gender Male-to-female and female-to-male transsexuals have the same mental functioning, characterized by splitting and denial. But there are differences, in part because society is more intolerant of feminine behaviors in men than of masculine behaviors in women. Male-to-female transsexualism includes a subgroup of subjects who, after failing in school, are unable to earn their living and live on welfare, even after surgical sex reassignment. We have learned from the study of intersexed and transsexual subjects that the feeling of belonging to a gender is a belief, a construction, in which psychological factors (interactions between the parents, the environment and the child) play an important role. Masculine or feminine identities have their roots in the sexual difference, but they are defined by each culture. A man is a male who accepts at least part of his culture’s stereotypes regarding masculinity. Even if biological factors play a role, they cannot explain the whole of gender identity and sexual orientation.  相似文献   

15.
Dieser dritte »Nomenklatorische Kurzbericht« informiert über die Anfang 1985 erschienene dritte Auflage des »International Code of Zoological Nomenclature« sowie über neue gutachtliche Entscheidungen (»Opinions«) der Nomenklatur-Kommission aus den Jahren 1980-1984 (Bulletin of Zoological Nomenclature, Band 37-41). Ältere derartige Entscheidungen, soweit sie fossile Taxa betreffen, sind im »Nomenklatorischen Kurzbericht, 1« (Paläont. Z.,46 (3/4): 251-255, 1972) und im »Nomenklatorischen Kurzbericht, 2« (Paläont. Z.,54 (3/4): 343-349, 1980) zusammengestellt.  相似文献   

16.
In the last decade numerous evolutionary models have been proposed and intensively discussed. Surprisingly, the logical analysis of these different hypotheses is not of great importance in this debate. As a matter of fact, Neodarwinism is a consistent deductive system which is based on few but wellconfirmed axioms. Hence, very often, precise statements and definitions of standpoint can be made. This is exemplified by some repeatedly discussed models concerning the problems of Darwinian »adaptation« and »natural selection« 1. Following the logic of the Neodarwinian theory, extinction can only be the result of overspecialization if some very unusual assumptions are made. 2. The hypothesis of »punctuated equilibrium« GOULD 1982), the »effect hypothesis« (VRBA 1983) and the stochastic evolutionary model SCHOPF 1979) include elements which are logically inconsistent with the »modern synthesis«; they could be »true« only if at least one of the neodarwinian axioms (so far not disproved) is negated.  相似文献   

17.
The present paper focuses on the interethnic comparison among three endogamous groups (a higher caste, a tribe and a religious group) with different ethnohistorical background. A total of 700 individuals were studied from their anthropometric and dermatoglyphic traits along with their asymmetries. Statistical comparisons were carried out through the use of student’s ‘t’ test and Sanghvi’s T2 statistics. Heterogeneity for most of the anthropometric and some dermatoglyphic traits supports their different origins. Though dermatoglyphic asymmetry doesn’t reveal significant discrimination, heterogeneity in anthropometric asymmetry corroborates with their different occupations. The anthropometric distances show greater values than the dermatoglyphic distances. This difference is probably due to the fact that anthropometry is not independent of environment and not a stable character like dermatoglyphic traits.  相似文献   

18.
Five different endogamous populations encompassing the main social ranks in the caste hierarchy of West Bengal, India were analyzed. To compare variability in populations with contrasting ethnohistorical backgrounds, analysis of variance, Scheffe's test and cluster analysis were performed, as based on dermatoglyphic variables, namely, 22 quantitative traits and 36 indices of diversity and asymmetry. The present study reveals that: 1. Overall disparities among the 5 populations are expressed only in finger ridge counts on the Ist and Vth digits and PII, in a-b ridge counts, in endings of main lines A and D, and in MLI on the palms; 2. Heterogeneity is greater in fluctuating asymmetry than in directional asymmetry; 3. There is a greater heterogeneity in the 22 quantitative traits than in the 36 indices of diversity and asymmetry, with females contributing more than the males; 4. The highest contribution to population variation is by Lodha among five populations; 5. Inter-group variations are homogeneous in most of the variables, which does not correspond with the relationships to caste hierarchy of these populations; 6. The dendrograms based on dermatoglyphic variables demonstrate that the traditional grouping of Indian populations, based on caste hierarchy, may not be a reflection of their genetic origin, in that the pattern of clustering corresponded best with the known ethnohistorical records of the studied populations; 7. Hence, dermatoglyphic affinities may prove quite useful in tracing the ethnohistorical background of populations.  相似文献   

19.
Abstract

«Saxifraga berica» (Béguinot) D. A. Webb and «Asplenium lepidum» Presl on the «Colli Berici». – We have identified a new association in the small caverns of the calcareous rocks in the hills of the north-eastern zone of the «Colli Berici», rising from the Italian plain near Vicenza. We have adopted for this association the name: ADIANTO-SAXIFRAGETUM BERICAE. This phytocoenose is characterized by the endemic «Saxifraga berica». We have found new stations of this remarkable plant and reported some features of this species to complete the diagnosis of D. A. Webb. In two station of this association we have found also the rare «Asplenium lepidum», new for this region.  相似文献   

20.
Abstract

In the cytological literature and text-books, the term cryptopolyploidy is mainly ignored and sometimes re-interpreted and often wrongly quoted from the point of view of historical accuracy. The paternity over this term should be ascribed to Chiarugi (1933), although Jaretzky (1928a, b), while investigating karyologically two species of the genus Bunias, B. orientalis and B. erucago, first advanced a concept of «verkappte Polyploidie» to indicate the occurrence of chromosomes of enlarged size hypothetically due to fusion of homologous members (Jaretzky's «Sammelchromosomen»). By such homologous chromosome fusion a polyploid karyotype could appear as a diploid karyotype. A pupil of Chiarugi, Roma Melinossi, reinvestigating the two species quoted by Jaretzky, Bunias orientalis and B. erucago, documented a quite different karyological state for these species, cf. Melinossi (1935, 1937), that is the presence of the same karyotype (2n=14) in both species and the occurrence of chromosome of doubled size in B. erucago. Melinossi recognized B. erucago to be the cryptopolyploid species (obviously crypto-tetraploid) and not B. orientalis as assumed by Jaretzky and reinterpreted the chromosomes of doubled size as the result of a «duplicazione endocromosomica» (MELINOSSI, 1937).

Almost contemporaneously a second pupil of Chiarugi, Fernanda Pannocchia-Laj, in a karyo-embryological investigation of some species of the genus Vinca, described the occurrence of another case of cryptopolyploidy (sense Melinossi, that is by «duplicazione endocromosomica»). Besides the minor fact that this latter author spelled the term «criptopoliploidia» also as «criptopoliploidismo», her paper is very remarkable because suggested the probable occurrence of a degree of cryptopolyploidy higher than that of Bunias (crypto-tetraploid), namely the occurrence of «… una entità criptopoliploide con valore superiore al tetraploide, probabilmente ottoploide» (cf. PANNOCCHIA-LAJ, 1938 p. 177, p. 178, Fig. 36: criptottoploide).

On the basis of the results of a comparative karyological study between Vinca minor, V. major and V. difformis, PANNOCCHIA-LAJ ascribed to V. minor the diploid karyotype «2n=46», to V. major the tetraploid karyotype «2n=92», and to V. difformis the cryptopolyploid karyotype «2n=46 (x4?)». Since PANNOCCHIA-LAJ (1938, pp. 184–185), following MELINOSSI (1937), interpreted the origin of cryptopolyploidy as a phenomenon due to «duplicazione endocromosomica», the formula «2n=46 (x4?)» clearly means occurrence of «doppia duplicazione endocromosomica» or «quadruplicazione cromosomica».

The author is personally aware that PANNOCCHIA-LAJ intentionally, for scientific prudence, avoided to include such a terms in her account.

The papers of CHIARUGI, MELINOSSI and PANNOCCHIA-LAJ have been largely ignored by the subsequent cytological literature and the term cryptopolyploidy has been variably quoted or interpreted and also reinvented (cf. HOLT in SPARROW & NAUMAN, 1974)!

From a terminological point of view, there are two sound considerations which suggest a refusal of the term cryptopolyploidy, namely:

- the prefix crypto does not qualify, it only means that such a polyploidy is «not visible» (hidden) by the methods of the observer;

- the choice of the prefix crypto is injustifiable because, the cases of cryptopolyploidy show the general morphology of the relative known polyploid species, that is they are phenotypically polyploids!

Both considerations, together, suggest the refusal of the prefix crypto and the proposal of the neoterm phenopolyploidy (phenotypic polyploidy). Necessarily, the indication of phenopolyploidy is nothing else but a provisional term waiting for a modern reinvestigation of both the crypto-tetraploid Bunias erucago and the crypto-octoploid Vinca difformis.  相似文献   

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