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1.
Present investigation deals with cytogenetical consequences (using attributes namely, seed germination, seedling length, mitotic index, mitotic and meiotic abnormalities and pollen grain sterilities) of cadmium sulphide (CdS) and copper oxide (CuO) nanoparticles (NPs) treatment in Coriandrum sativum L. (Family: Apiaceae, spice of commerce). Ethyl methanesulphonate (EMS), a conventional mutagen is used as positive control. Results suggest that both CdS- and CuO-NPs can induce growth inhibition and cause cytological aberrations in both mitotic and meiotic cells in the studied species. EMS also responds similarly as that of NPs. Study highlights that rooted plant species can be effectively used as model for assessment of nanotoxicity considering cytogenetical parameters.  相似文献   

2.
Man appears to be unique among mammals with respect to very high level of reproductive wastage. It seems reasonable to suppose that many early losses attribute to cytogenetical abnormalities. However, this stage of pregnancy is difficult to be studied. The investigation of gametes is one of the most reliable ways to estimate the cytogenetical disorders in early life. The results from cytogenetical analysis of human male gametes are summarized.  相似文献   

3.
Kupriianova LA 《Tsitologiia》2004,46(7):649-658
Results of the author's long-term study of the karyotype of Lacerta (Zootoca) vivipara (family Lacertidae, Sauria) have been generalized and supplemented with relevant literature data. Within the species an interpopular karyotype variability was established, and several chromosomal forms were described. Karyotypes of L. (Z.) vivipara from four new, previously not examined populations have been first presented in this paper, and cytogenetical features of their chromosomes are given. Finally, cytogenetical analysis of particular specimens from different localities enabled the author to reveal a new chromosomal form and to define the limits of distribution of other forms of the species. The complex L. (Z.) vivipara has appeared to be more complicated than earlier believed. This complex includes several chromosomal forms of unclear taxonomic status, and some subspecies characterized by various modes of reproduction and distinct distribution ranges. It has been confirmed that in the complex L. (Z.) vivipara intensive chromosomal changes accompany the processes of form-formation and subspeciation. Some cytogenetical regularities of these processes have been demonstrated and compared with hybridogeneous form-formation and speciation. Based on the critical analysis of the available karyological data, some mechanisms of chromosomal changes were described, and their tendencies were determined. In addition, intraspecific relationships were analysed. The proposed scheme was compared with the pattern of intraspecific phylogeny of L. (Z.) vivipara based on molecular data. It has been shown that a high cytogenetical differentiation of the found chromosomal forms and subspecies is correlated with their low morphological differentiation and with a rather low genetical differentiation. The results of the combined analysis suggest the leading role of cytogenetical data for understanding the processes of form-formation and subspeciation. The importance of chromosomal rearrangements in these processes is emphasized, with special reference to their role in the evolution and phylogeny of the complex L. (Z.) vivipara. Some modes of form-formation and subspeciation in this complex are discussed.  相似文献   

4.
It has been shown that in seed progeny of Quercus robur L., Pinus sylvestris L. and Betula pendula Roth. some cytogenetical characteristics vary under conditions of contamination. Such changes may be common or specific type. Thus, the frequency of pathological mitosis increases under such conditions in all the investigated species of trees. Inhibition of mitosis was found in the progeny of the pine, and variability in the number of nucleoli was detected in the pine and oak. However, in some cases the level of pathological mitosis in the oak progeny did not differ from the control, but the mitotic activity was higher due to the presence of much more cells being at the prophase stage. In the birch progeny under conditions of contamination the mitotic index increased, with a simultaneous shifts in the peaks of mitotic activity. The possibility of using these cytological characteristics for the aims of cytogenetical monitoring is considered.  相似文献   

5.
A cytogenetical examination of a boy aged 4 with congenital mental deficiency and multiple anomalies of its phenotype has revealed unbalanced translocation (18, 22) (18 qter----cen----22 qter).  相似文献   

6.
The anatomical and cytogenetical findings on a three quarter Charolais heifer which failed to show oestrus are described. The heifer had a karyotype of 60, XY in all tissues studied and was sex chromatin negative. The vulva and vagina were normal, the cervix had a double external os, the left ovary was partially hypoplastic, there was no right gonad and a cystic dilatation of the fallopian tube was recorded.  相似文献   

7.
Cytogenetical studies of cosmonauts' peripheral blood lymphocytes after space flights on MIR orbital station showed a statistically significant increase in the yields of radiation-induced chromosomal aberrations. However, similar studies with in vitro irradiation of biological objects with accelerated charged particles are of great importance for elucidation of the nature of cytogenetical damage induced in vivo. It is also important to investigate the structure of cosmonatus' diseases over their life, in particular, lens opacities and oncological diseases. Thus, the purpose of the investigations planned is to study cytogenetical damage in blood lymphocytes from cosmonauts after space flights on the ISS in vivo, as well as in donor blood lymphocytes after in vitro exposure to accelerated charged particles. The tasks of the project are as follows: determination of the yields and types of chromosomal aberrations in cosmonauts' blood lymphocytes before and after space flights, comparative studies of biological effects induced in vitro by different types of ionizing radiation in human blood lymphocytes in ground experiments, assessment of cytogenetical risks, analysis of the structure of cosmonatus' diseases comparing with that of whole population, study of the mortality and frequency of cataracts and oncological diseases in cosmonauts. The results to be obtained will be used for setting of health norms applied to the influence of radiations of different types, and for elaboration of measures to reduce health risks from space flight factors.  相似文献   

8.
We report a case of a stillborn infant that presented multiple birth defects and a diploid/tetraploid mosaicism in skin fibroblasts. Clinical and cytogenetical findings are discussed and compared with those presented in previously reported cases.  相似文献   

9.
Abstract The taxonomic relationships of 53 species (122 strains) in subtribe Brassicinae were studied by using Euclidian distances calculated from 53 metric characters. Through cluster analysis applied to the species and subspecies in the genus Brassica , six large clusters could be defined. By the same method, Diplotaxis was grouped into four clusters, Erucastrum into two, and Sinapis into two. These clusters coincided in general with the taxonomic sections of Schulz (1936), but some exceptions were noted. Most of the exceptional species were those placed in critical positions by cytogenetical observations. It was found that cluster grouping reflected the cytogenetical relations of species fairly well.
Relationships among clusters and genera are represented by a Euclidian distance matrix, and the evolutionary trends of those taxa are discussed. Clusters B-3 (in Brassica) , D-1 ( in Diplotaxis ) and E-1 (in Erucastrum ) are closely related to each other, forming a complex. This complex is closely related to Sinapidendron. It is postulated that this complex and Sinapidendron might have retained some characters in common with their putative ancestor. Species in the other clusters are considered to be derived from that hypothetical ancestor in the course of evolutionary divergence.  相似文献   

10.
The cytogenetical examination of 26 rural inhabitants in Karaganda region living near the nuclear proving ground was carried out. The significant excess of chromosomal type aberrations above the chromatid type was found in all the examined individuals as well as in old age group and males.  相似文献   

11.
The results of cytogenetical analysis of human oocytes are summarized. The chromosomal disorders in human gametes and in spontaneous abortions are comparatively analyzed.  相似文献   

12.
Giemsa and Ag-staining techniques and C-banding were performed on cytological preparations of 22 specimens of silversides (Odontesthes bonariensis) in order to extend the karyological knowledge on the family Atherinidae, to contribute cytotaxonomically to the systematics of the species and to identify possible cytogenetical markers of the introduced population.The karyotype is conservative, 2n being 48, and 44 chromosomes being uniarmed. The remaining four biarmed chromosomes show intraindividual morphological variability. This variability is sex-independent. Ag-stanining techniques reveal that NORs are located on the short arms of biarmed chromosomes and that the morphological variability is partially due to NOR activity. C-banding revealed the associations between NORs and constitutive heterochromatin which could be responsible for some apparent structural differences. The differences found could be cytogenetical markers of the introduced population.Research work supported by CNR, Italy. Special grant I.P.R.A. — Sub-project 1. Paper No. 1192.  相似文献   

13.
A V Katokhin 《Genetika》1989,25(10):1786-1792
Gene Acph-1 coding for acid phosphatase was localized on Drosophila virilis chromosome 2 in the region 20A-20E and in D. texana and D. imeretensis homologous regions of the chromosomes 2. Gene Lap-1 coding for leucine aminopeptidase was linked to Acph-1 gene and localized in the 20E-20G region for these Drosophila species. The cytogenetical localization of two genes was determined after analysing recombinant chromosomes by isozymic and cytological methods in the progeny of interspecific hybrids.  相似文献   

14.
Time-dependent effects of lead (Pb) toxicity were studied in Algerian mice (Mus spretus) treated with Pb acetate via drinking water (1 g Pb acetate/L) for different periods of exposure (15, 45, and 90 d). End points included the determination of hepatic Pb concentration and the assessment of some morphophysiological, biochemical and cytogenetical parameters. A control group receiving distilled water was also monitored for comparative purposes. Hepatic Pb accumulation increased with the time of exposure and was significantly higher in treated mice when compared to controls. In association with significant body mass loss in Pb-exposed mice, for 15 and 45 d, a significant increase in the relative spleen mass was observed after 45 d of intoxication. Pb-exposed mice also showed significant decreases in red blood cells, hematocrit, and mean corpuscular hemoglobin. On the contrary, changes in plasma transferases (aspartate aminotransferase and alanine aminotransferase) and hepatic superoxide dismutase activities did not reach statistical significance. A significant increase in the frequency of micronucleated polychromatic bone marrow erythrocytes was also found in the 90-d-exposed mice, compared to nontreated mice and the other exposed groups. Exposure to Pb acetate resulted also in a slight time-dependent decrease of the polychromatic-normochromatic ratio. These results support the concept that a long-term chronic exposure to Pb induced alterations upon some morphophysiological and genetic parameters in Algerian mice.  相似文献   

15.
Diploid gynogenesis was induced in Siberian sturgeon Acipenser baeri using ultra violet (UV)-irradiated bester ( Huso huso × Acipenser ruthenus ) sperm. The higher survival rate of meiotic diploids was noted after 1350 ergs mm−2 UV irradiation. A total of 80 meiotic diploids of known parentage from two different experimental treatments were screened using microsatellite DNA and cytogenetical analysis, and uniparental transmission in meiotic diploids was confirmed.  相似文献   

16.
Infraspecific cytogenetical variation was studied in a diverse collection of five non-cultivated and cultivatedCucumis sativus accessions. The individual chromosomes of different accessions could be identified by the C-banding pattern and chromosome measurements. About 40–50% of the genomic area are made up of heterochromatin inC. sativus. The non-cultivated accessions exhibit more heterochromatin and lower chiasma frequencies per pollen mother cell than cultivated accessions. There is infraspecific variation in C-banding pattern, karyomorphology and multinucleolate cells. The use of C-banding in infraspecific classification is discussed.  相似文献   

17.
Summary Basal cells of the hard palate epithelium have been examined electronmicroscopically. Secretory granules, morphologically similar to those of the Merkel cells, occur in the groups of basal cells. A comparison concerning the cytoplasmic qualities of the two cell types is given, and the possibility of a cytogenetical or physiological relationship between the Merkel cells and the basal cells is discussed.Supported by the Agricultural Research Council of Norway.  相似文献   

18.
In accordance with the fundamental principles of the radiation cytogenetics the scheme of cytogenetical examinations of individual radiosensitivity of relatively healthy donors on the basis of chromosomal test (G2-assay) has been developed and tested.  相似文献   

19.
E P Gus'kov  T P Shkurat 《Genetika》1985,21(8):1361-1367
High pressure of oxygen induces chromosomal rearrangements in metaphases of human peripherical blood cells treated in vitro. An increase in the percentage of rearrangements was detected in the third mitosis, due mainly to chromatid breaks. The data of cytogenetical analysis of lymphocytes of human blood treated in vivo at 3 ata for 30 min are presented. A differential character of distribution spectrum of chromosomal aberrations induced after in vivo and in vitro treatment was noted. Some unusual alterations in chromosome morphology are described, namely, solid, not stained clear lense-like bodies surrounded by chromatin and localised in the long arm of chromatids.  相似文献   

20.
A study of three new cases with different trisomies involving chromosome 9 and a review of about 100 cases of partial trisomy 9 reported in the literature, suggested some cytogenetical and clinical correlations and lead us to propose the nomenclature of Rethore's syndrome type 1 and type 2.  相似文献   

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