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21.
Method of creation computer models of upper floor of abdomen organs: liver, gallbladder, duodenum, pancreas, stomach, blood vessels with using computer system "DUCT" was described. Details of modelled structures of the cylindric and complicated forms were noted.  相似文献   
22.
Morphofunctional features of skin mast cells located in the areas subjected to chronic UV-radiation and in the associated basal cell carcinoma with photoinjure have been studied. Various immunohistochemical methods (chromogranin A, CDla, HLA-DR, CD35, Ki67, P53, Bcl-2, Mcl-1, involucrine) were used. It is found that chronic UV-damage leads to mast cell hyperplasia as well as activation of their synthetic, absorption and secretory functions. It is suggested that mast cell hyperplasia and increase of mast cells neuroendocrine activity provide a risk of basal cell carcinoma development.  相似文献   
23.
Gene P504S is considered as the most specific for prostatic carcinoma and its protein (alpha-methylacyl coenzyme A racemaze (AMACR/P504S) is higly sensitive and specific marker not only for adenocarcinoma cells but also for preceding changes - prostatic intraepithelial neoplasm (PIN). AMACR/P504S seems to be the first marker of malignant transformation and tumor progression. Use of immunohistochemical method for revealing this marker together with methods of basal prostatic cells observation (cytokeratin of a high molecular weight, cytokeratin 5/6, p63) improves morphological diagnosis of prostatic carcinoma, particularly on the material of needle biopsies. This combination allows one to identify neoplastic nature of some difficult lesions.  相似文献   
24.
Histological, histochemical and immunohistochemical studies of 50 solitary juvenile polyps (JP) and 50 JP from children with juvenile polyposis syndrome (JPS) were performed. Observations of the focal complex glandular structures with high mitotic rate were more frequent in JP from patients with JPS (n = 29, 58%) than in solitary JP (n = 17, 34%) (p < 0.03). The immunohistochemical study demonstrated p53 overexpression in individual cells and more than 50% of Ki-67-positive cells in 5 (10%) solitary JP and in 17(34%) JP from patients with JPS (p < 0.007). The finding of microglandular pattern is more typical for JP from patients with JPS. Pathological data, expression of p53 and Ki-67 by immunohistochemistry could help to pick out the group of JP with dysplastic changes.  相似文献   
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Phylogenetic analysis of nucleotide sequences of gag and env genes of type 1 human immunodeficiency virus (HIV-1) variants isolated from individuals infected through sexual intercourse or nosocomially (by injections with nonsterile syringes) showed that 5 of 27 (18.5%) isolated strains were recombinants. Two viruses found in the Russian Far East had gagAenvE genotype, three other recombinants had envG genotype; gag gene of one isolate belonged to subtype A and gag genes of two others belonged to subtype D. Detection of new recombinant variants in addition to the A/B recombinant described previously shows that these viruses can contribute to the HIV-1 genetic variability in Russia.  相似文献   
27.
Eleven of 15 ferrets experimentally infected withBrugia malayi became amicrofilaremic after a brief patency; only four ferrets remained patent after 6 months of infection and two of these ferrets developed a high, persistent microfilaremia. Blastogenic responses of peripheral blood lymphocytes to antigens of microfilariae (mf), assayed in vitro, demonstrated an antigen sensitivity at prepatent, patent and postpatent periods of infection. Lymphocytes from ferrets with high microfilaremia had elevated background responses in culture which were directly correlated with the number of circulating mf. This background response was attributed to antigenic stimulation by mf present in the lymphocyte cultures; addition of mf to cultures of lymphocytes from postpatent ferrets induced responses equivalent to those observed in microfilaremic ferrets. Lymphocyte responses to the mitogen, concanavalin A, did not differ significantly among microfilaremic, amicrofilaremic and uninfected ferrets. Antibody in IgG to antigens of mf measured by ELISA and by immunoblots from SDS-PAGE showed similar patterns of response in ferrets which became amicrofilaremic and in the few ferrets which remained microfilaremic. Prausnitz-Kustner tests demonstrated no consistent differences in titers to microfilarial antigens between patent and amicrofilaremic ferrets. The results suggest a high level of immune responsiveness to antigens of mf in infected ferrets with no evidence of immunosuppression associated with prolonged microfilaremia or of major changes in immune responses with development of amicrofilaremic infections.  相似文献   
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The lamellar bone mineral component in mature and senile age was studied using the methods of transmission electron microscopy and cryofractography. This component was shown to be formed by crystals (13-4 x 7-8 x 3-4 nm) of the prismatic shape that formed coplanar units (29-3 x 18-21 x 3-4 nm). The peculiarities of mineral particle distribution inside and between the collagen fibrils, as well as on the completely formed areas of bone surface, were detected. It was established that the length and the width of coplanar crystal aggregates was significantly higher in senile age as compared to similar linear parameters defined in persons of mature age (by 17-20 and 5-9%, respectively).  相似文献   
30.
INTRODUCTION: Cardiopulmonary bypass (CPB) induces an inflammatory response believed to contribute to postoperative morbidity. We hypothesized that the magnitude of the inflammatory response following CPB would be associated with adverse clinical outcomes. METHODS: Twenty-nine patients had plasma TNF, IL-6, IL-8, elastase, histamine, complement C5a, and complement C3a measured by ELISA before, during, and after cardiac operations employing CPB. Inflammatory mediator levels were analyzed with respect to outcomes. RESULTS: Mediator levels peaked at 4 h post-CPB and either returned to baseline or substantially decreased by 24 h. Patients with peak mediator levels above the median for the group as a whole were classified as 'hyper-responders'; those with levels below the median were classified as 'normal responders'. While IL-8, C3a, and IL-6 levels were independently associated with adverse outcomes, TNF, histamine, and C5a levels were not. Elastase levels trended towards adverse outcomes. IL-8 'hyper-responders' experienced significantly greater postoperative weight gain and had higher IL-8 levels at 24 h (p<0.05), with trends towards renal impairment and protracted supplemental oxygen requirements. C3a 'hyper-responders' strongly trended towards increased bleeding, delayed extubation, greater postoperative weight gain, and decreased levels of independent functioning at discharge (p < or = 0.10). IL-6 'hyper-responders' experienced significantly more postoperative bleeding, delayed extubation, and higher IL-6 levels at 24 h compared to 'normal responders' (p < 0.05). They strongly trended towards greater postoperative weight gain and decreased levels of independent functioning at discharge (p < or = 0.10). CONCLUSIONS: Patients who have an exaggerated inflammatory response to CPB tend to bleed more, require more respiratory support, demonstrate greater capillary leak via weight gain, and display a decline in independent functioning relative to normal responders. Thus, it appears that the magnitude of the inflammatory response to CPB adversely influences clinical outcomes.  相似文献   
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