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71.
Twenty-four feline spontaneous basal cell carcinomas (BCCs) were analyzed by computerized nuclear morphometry. The study included 15 non-recurrent and 9 recurrent tumours. In each case, the nuclei of at least 100 neoplastic cells were measured, and the mean nuclear area (MNA), mean nuclear perimeter (MNP) and mean nuclear diameter (MND) were calculated. The analysis of data of the non-recurrent BCCs and the recurrent tumours revealed statistically significant differences between those groups (p<0.001) as well as between infiltrative and clear types of BCCs (p<0.05). The results indicate that nuclear morphometry is able to predict recurrent tumour growth and helps to differentiate histological subtypes of BCCs in cats.  相似文献   
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Embryo transfer using cryopreserved B. indicus embryos results in low pregnancy rates. The low viability of B. indicus embryos is likely a result of their low freezability relative to embryos from other species, notably B. taurus. Freezability is probably related to the quantity of lipid droplets in the embryonic cells. However, the mechanism underlying this association is unknown. Using multiphoton and transmission electron microscopy, the proportion, volume, morphology and composition of lipid droplets in fresh and cryopreserved B. indicus and B. taurus embryos were studied. B. indicus embryos have more droplets than B. taurus and a greater percentage of lipid droplets in clusters (34% vs. 24%; < 0.05). Also, B. indicus individual droplets are of greater volume than those of B. taurus (47 μm3 vs. 34 μm3; < 0.05). After freezing, the percentage of clusters decreased in B. indicus (11% vs. 5%; < 0.05), while in B. taurus they increased (2% vs. 7%; < 0.05). Freezing influenced the lipid droplet morphology, increasing the number of cracked droplets in B. indicus embryos (33% fresh vs. 62% frozen; p < 0.05), but not in B. taurus embryos (35% fresh vs. 34% frozen; ns). Regarding composition, saturated lipid droplets prevail in B. indicus embryos, contrary to B. taurus embryos. We observed differences in lipid droplet organization, proportion, volume, morphology and composition between B. indicus and B. taurus embryos which are altered in opposite directions following freezing.  相似文献   
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Immunodeficiency manifested by a decrease in the content of T and B lymphocytes and complementary activity of blood serum and phagocytic activity of neutrophils, absence in most of them of theophylline-sensitive T lymphocytes with suppressor activity, and an increase of immunoglobulin M content are noted in piglets predisposed to respiratory pathology.  相似文献   
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It has been established that correcting the metabolic status 15–60 min after birth (before the first ingestion of colostrum), directed at stabilizing processes of free-radical oxidation and acid-base state in newborn calves, promotes the creation of a higher level of colostral immunity and is the basis for reducing the development of neonatal diseases.  相似文献   
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Lignin deposition at consecutive secondary wall thickening stages of early and late xylem cells during annual ring wood formation in Scots pine (Pinus sylvestris L.) stems was studied. Lignin patterns, isolated by thioglycolic acid method, consisted of alcohol-soluble (LTGA-I) and alkali-soluble (LTGA-II) fractions. The sum of two fractions, being the total lignin content, gradually increased in the course of lignification. However, the increments of lignin amount at each development stage of early and late tracheids were different. The intensity of lignin deposition increased in the course of earlywood tracheid maturation and decreased toward the end of latewood cell differentiation. The deposition of two lignin fractions in each layer of forming wood also occurred oppositely. The increment of LTGA-I descended, whereas that of LTGA-II increased from the beginning to the end of early xylem lignification. In contrast, LTGA-I increment dropped, whereas LTGA-II rose during late xylem lignification. Gel permeation chromatography showed that the lignins, formed at the beginning of lignification, were more homogeneous and had higher molecular weight compared with the lignins at the end of cell differentiation. Besides, the content of cellulose, estimated as the residue after lignin isolation, and of cell wall substances, presented as cell wall cross-section areas, at consecutive maturation stages of early and late xylem cells have been found to be different. The data show that lignin deposition occurred in different conditions and with opposite dynamics during early and late xylem formation.  相似文献   
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Lotus creticus is a potentially important perennial legume for soil management in the Mediterranean climate. This plant is in focus of experimental research in different countries. The so-called Lotus creticus group is taxonomically problematic. Although some authors consider all members of the group as a single variable species, others segregate several species distinct from L. creticus, especially L. cytisoides. Recent morphological studies suggested that L. creticus and L. cytisoides are taxonomically distinct at specific level and not even closely related to each other. Two molecular phylogenetic studies published so far and based on one accession of L. creticus each gave conflicting results on relationships of this species. In this paper, sequences of nuclear ribosomal ITS (nrITS) are produced from multiple accessions of both L. creticus and L. cytisoides. Taxonomic identity of each accession has been tested using morphology. The new nrITS sequences are inserted in a data matrix containing a representative set of Lotus species covering all the geographical range and all major taxonomic groups of Lotus. Phylogenetic analysis of nrITS sequence data showed that L. creticus is related to L. assakensis and other species of the section Pedrosia while L. cytisoides is related to L. longisiliquosus and other species of the section Lotea. These results are important for establishing future germplasm collection, breeding and selection programs of perennial Lotus species.  相似文献   
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