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Comparative chromosome painting with individual human chromosome-specific libraries (CSLs) on cattle metaphase chromosomes delineated 46 homologous chromosomal segments between the two species. Continuous arrangement of these segments on individual cattle chromosomes demonstrates a nearly complete coverage of the bovine karyotype and shows physical boundaries of bovine chromosomal segments homologous to individual human chromosomes. Alignment of the available comparative gene mapping data with the homologous segments strongly supports the detected gross homologies between the karyotypes of the two species. In addition to cattle, four human CSLs were hybridized to sheep metaphase chromosomes also, to further verify the known karyotype homology within the Bovidae. Besides its application to karyotype evolution research, the comparative knowledge provides for rapid expansion of the much needed Type I locus-based bovine gene map. Received: 9 September 1995 / Accepted: 4 December 1995  相似文献   
3.
An attempt has been made to study and compare the incidence and variations in the pterion formation in the skulls of 40 Nigerians and 72 Indians obtained from the Department of Anatomy, University of Jos, Nigeria. The present study concludes: 1. All the three varieties of pterion i.e. sphenoparietal, frontotemporal and stellate are found in both races. 2. The frequency of sphenoparietal pterion is high in both races (Indians 95.3%, Nigerians 84.79%) while the frontotemporal (Indians 3.46%, Nigerians 10.11%) and the stellate (Indians 1.38%, Nigerians 5.06%) pterion are more common in Nigerians. 3. The frequency of epipteric bone is high in Indians (Indians 11.79%, Nigerians 3.79%) and is more commonly associated with sphenoparietal pterion. 4. No epipteric bone is associated with stellate pterion in both races. 5. The difference in the distance of pterion from the zygomatic arch is highly significant between two races on both sides. 6. The difference in the distance of pterion from the frontozygomatic suture is insignificant between the two races. 7. The frequency of "high Pterion" is more in Nigerians on both sides. 8. The frequency of "Backward Pterion" is more in Indians on the right side, whereas little more in Nigerians on the left side.  相似文献   
4.
Pancervicovaginal smears taken from 350 women using an intrauterine contraceptive device (IUD) were screened for the presence of actinomycetes organisms. Of the 12 cases in which actinomycetes-like organisms were seen in Papanicolaou-stained smears, the presence of actinomycetes organisms was confirmed by immunofluorescence in 10 cases. The prevalence of actinomycetes infection was thus 2.8% (10 of 350 cases) in the IUD users. Eight (4.3%) of 173 symptomatic subjects had actinomycetes infections. Two of the positive cases were asymptomatic. Eight of the ten patients with confirmed actinomycetes infection were using the Cu T device while two were wearing the Lippes Loop IUD. Seven of the ten patients had been using an IUD for more than two years. The time of insertion of the IUD (postpuerperal, postmenstrual or after medical termination of pregnancy) did not show any correlation with the presence of actinomycetes infection. Actinomyces israelii was responsible for the infection in eight cases while Arachnia propionica was seen in two cases. The organisms could not be grown in culture.  相似文献   
5.
Summary Corn plants were grown in pots to study the effect of post-planting loosening of an unstable sandy loam soil on the anatomy of roots. Roots from compact soil had more elaborate production of sclerified cells in the cortical and vascular tissue which may be considered as traits developed in such roots to resist external forces to prevent the deformation of interior cells. It appears that the compact layer that developes on unstable soils after irrigation, hinders the normal development of root structure. Its loosening decreases soil resistance and permits normal development of root anatomy.  相似文献   
6.
A comprehensive genetic linkage map of the porcine genome has been developed by typing 128 genetic markers in a cross between the European Wild Boar and a domestic breed (Large White). The marker set includes 68 polymerase chain reaction-formatted microsatellites, 60 anchored reference markers informative for comparative mapping and 47 markers which have been physically assigned by in situ hybridization. Novel multipoint assignments are provided for 54 of the markers. The map covers about 1800 cM, and the average spacing between markers is 11 cM. We used the map data to estimate the genome size in pigs, thereby addressing the total recombination distance in a third mammalian species. A sex-average genome length of 1873 +/- 139 cM was obtained by comparing the recombinational and physical distances in defined regions of the genome. This is strikingly different from the length of the human genome (3800-4000 cM) and is more similar to the mouse estimate (1600 cM). The recombination rate in females was significantly higher than in males.  相似文献   
7.
Cell Biochemistry and Biophysics - Despite attempts to maintain asepsis, good manufacturing practices, and the use of terminal sterilization by millipore filtration, the nuclear practitioner is...  相似文献   
8.
Cancer cell lines play a crucial role as invaluable models in cancer research, facilitating the examination of cancer progression as well as the advancement of diagnostics and treatments. While they may not perfectly replicate the original tumor, they generally exhibit similar characteristics. Low-passage cancer cell lines are generally preferred due to their closer resemblance to the original tumor, as long-term culturing can alter the genetic and molecular profiles of a cell line thereby highlighting the importance of monitoring the passage number (PN). Variations in proliferation, migration, gene expression, and drug sensitivity can be linked to PN differences. PN can also influence DNA methylation levels, metabolic profiles, and the expression of genes/or proteins in cancer cell lines. When conducting research on cancer cell lines, it is crucial for researchers to carefully select the appropriate PN to maintain consistency and reliability of results. Moreover, to ensure dependability and replicability, scientists ought to actively track the growth, migration, and gene/or protein profiles of cancer cell lines at specific PNs. This approach enables the identification of the most suitable range of PNs for experiments, guaranteeing consistent and precise results. Additionally, such efforts serve to minimize disparities and uphold the integrity of research. In this review, we have laid out recommendations for laboratories to overcome these PN discrepancies when working with cancer cell lines.  相似文献   
9.
A porcine glucosephosphate isomeraseprocessed pseudogene has been isolated and sequenced. The pseudogene has several base substitutions as well as an insertion and deletions, and is 83% homologous to the corresponding cDNA. It contains an intervening sequence of 565 bp, is truncated at the 3 end, and is flanked by direct repeats of seven nucleotides. Fluorescent in situ hybridization to porcine metaphase chromosomes localized the processed pseudogene to Chromosome (Chr) 1q1.6-1.7. A (GT)14(AT)15 microsatellite was detected close to the processed pseudogene.  相似文献   
10.
The mapping strategy for the bovine genome described in this paper uses large insert clones as a tool for physical mapping and as a source of highly polymorphic microsatellites for genetic typing, and was one objective of the BovMap Project funded by the European Union (UE). Eight-three cosmid and phage clones were characterized and used to physically anchor the linkage groups defining all the bovine autosomes and the X Chromosome (Chr). By combining physical and genetic mapping, clones described in this paper have led to the identification of the linkage groups corresponding to Chr 9, 12, 16, and 25. In addition, anchored loci from this study were used to orient the linkage groups corresponding to Chr 3, 7, 8, 9, 13, 16, 18, 19, and 28 as identified in previously published maps. Comparison of the estimated size of the physical and linkage maps suggests that the genetic length of the bovine genome may be around 4000 cM. Received: 1 July 1996 / Accepted: 13 September 1996  相似文献   
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