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1.
The rate of intravascular hemolysis and associated complications was studied in 100 patients with rheumatic heart disease within 2 to 20 years after replacement of the heart valves. Hemolysis of varying intensity was recorded in 72% of patients, anemia in 5%, hemosiderinuria in 27%, cholelithiasis in 4%, and sideropenia in 36.8% of the examined. Renal failure was diagnosed in none of the patients. Thromboembolic complications were more frequently encountered in patients with hemolysis. In order to prevent anemia and sideropenia, it is recommended that control may be exercised over hemolysis and iron content in the blood of patients with prosthetic heart valves.  相似文献   
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Morphological features and immunophenotype of mature dendritic cells (DC) generated from the monocytes of healthy donor blood after culture with GM-CSF and IL-4 with the addition of TNF, were studied using light and electron microscopy, as well as flow-cytometry. It was shown that DC were characterized by a number of morphological features such as: large size, eccentrically located nucleus, highly developed system of extensions, large vacuolated cytoplasm, prominent and activated Golgi complex and ribosomal apparatus. Mature DC are characterized by active surface expression of MHC and co-stimulatory molecules (MHC I, MHC II, CD40, CD80, CD86).  相似文献   
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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   
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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   
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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   
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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   
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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   
10.
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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