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31.
Changes of the histological structure of rat's skin were studied two weeks following the daily applications of native birch tar and of purified birch tar, devoid of the components that could be potentially dangerous for humans. The morphometric investigations were performed with the use of computer technologies on the apparatus-programme complex (DiaMorph, Russia). It has been established that the main morphological manifestations of specific dermatotropic activity of birch tar in the present experiment included: epidermal hypertrophy, hyperkeratosis, stimulation of the activity of all dermal cellular elements, intensification of blood supply, reduction of sebaceous glands. Analysis of morphological findings indicates the bioequivalence of the native and purified birch tar in terms of its specific dermatotropic activity.  相似文献   
32.
Using light and electron microscopy structural bases for intracellular, extracellular and integrative regulation of synaptic efficiency and neuron sensitivity were established in rat sensomotor cortex. Intracellular regulation is realized basically through modulation of postsynaptic components of the synapse, while extracellular one is provided by synaptic endings of "recurrent" axons on GABA-ergic relay and interneurons. Integrative regulation is realized by means of concentration of similar axonal terminals in restricted cortical area and arrangement of "neuromediatory" pool.  相似文献   
33.
Different blood saving methods are analyzed in 2000 cardiac surgical patients undergoing coronary and vascular bypass surgery in 1993 to 2000. The basic blood saving methods are as follows: intraoperative autoreinfusion (normovolemic thermodilution), reinfusion of the patient's blood, preoperative autologous plasma donation in combination with aprotinine, aminocapronic acid, etc. An analysis revealed a decrease in homologous blood components intraoperatively. Red blood cell transfusion decreased from 100% in 1993 to 44% in 2000, fresh frozen plasma and platelet transfusions did from 98 to 39% and from 96 to 1%, respectively. Intraoperative homologous blood transfusion could be avoided in 70% of those undergone coronary bypass surgery.  相似文献   
34.
The present investigation was carried out to estimate the incidence of Epstein-Barr virus (EBV)-associated cases among gastric carcinoma (GC) patients in Russia. Carcinoma specimens from 184 patients with GC treated at the Cancer Research Center were investigated by EBV encoded RNA-1 (EBER-1) in situ hybridization. Seventeen (9.24%) cases showed uniform EBER-1 expression restricted to the carcinoma cells. Hybridized signals were not detected in the non-neoplastic gastric epithelium. EBV involvement was significantly more frequent among males, especially in the tumors belonging to less differentiated types (moderately differentiated tubular adenocarcinomas and poorly differentiated solid adenocarcinomas) and located in the upper stomach (cardia and middle part). Most EBV-positive GCs were characterized by great lymphoid compartment involvement. The findings of the distribution of EBV-positive. GCs by sex, site, and histology are similar to those in Japan; however, the detection rate of EBV-positive cases in Russia is higher than that in Japan (6.7%) and lower than that in the USA (16%).  相似文献   
35.
Indices of blood oxygen transport (hemoglobin-oxygen affinity, pCO2, pH, pO2, etc.) and prooxidant-antioxidant state (Schiff bases, conjugated dienes, catalase, retinal, alpha-tocopherol) were measured in rabbit blood and the liver during postischemic reperfusion. Hepatic ischemia was induced for 30 min by ligation of a hepatica propria, and reperfusion lasted for 120 min. Hepatic ischemia worsened blood oxygen transport. Restoration of arterial blood flow did not result in improvement of oxygen delivery. Moreover, marked metabolic acidosis was observed throughout 2 hr of reperfusion. Ischemia induced a shift of oxyhemoglobin dissociation curve to the right. This shift persisted after restoration of hepatic arterial blood flow facilitating increased oxygen transport to tissues. Changes in blood oxygen transport during hepatic ischemia/reperfusion were accompanied with high activity of free radical processes. During reperfusion, the largest increase in content of lipid peroxidation products and the greatest fall of some antioxidant levels except catalase were observed indicating impairment of liver prooxidant-antioxidant balance. The results showed that activation of lipid peroxidation and a decrease in some antioxidant levels during hepatic reperfusion were associated with lowering of hemoglobin-oxygen affinity and suggest participation of the latter in impairment of prooxidant-antioxidant balance.  相似文献   
36.
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   
37.
The aim of this paper is an analysis of clinical documentation and results of autopsy of 21 patients (pts) who died of invasive aspergillosis (IA) in the Institute of Tuberculosis and Chest Diseases in years 1993-2000 and the assessment of predisposing factors for IA. In 17 pts IA was the main and in other 4 only an accessory cause of death. All pts were treated with corticosteroids and/or cytostatic drugs--because of lung cancer (11 pts), cancer in other site (2 pts), haematologic disorders (2 pts), Wegener's granulomatosis (1 pt), polymyositis (1 pt), idiopathic pulmonary fibrosis (1 pt) and other diseases (3 pts). In 15 out of 21 pts granulocytopenia was revealed (from 0.008 x 10(9)/L to 0.82 x 10(9)/L) on an average one month before death. In 15 pts IA was limited to the lungs, in 6 others there were also fungal lesions in brain, kidneys, liver, spleen and heart. Pts with disseminated form of IA had significantly lower granulocyte count and were treated with higher doses of corticosteroids than others. Immunosuppressive drugs and granulocytopenia can be regarded as predisposing factors. Fatal course of IA depended also on the late diagnosis.  相似文献   
38.
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   
39.
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   
40.
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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