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41.
In this study we analyzed by immunohistochemistry the expression of TGF-beta1 protein and TGF-beta receptors I and II in 4 low-grade dysplastic nodules, 2 high-grade dysplastic nodules, 6 early, 22 small, and 62 advanced hepatocellular carcinomas. The expression of TGF-beta1 protein by hepatocytes was decreased in advanced hepatocellular carcinoma compared with small or early hepatocellular carcinoma(P < .05). Frequent and intense staining of TGF-beta1 protein was noted in the sinusoidal endothelium of advanced hepatocellular carcinomas despite of its decreased staining in hepatocellular carcinoma cells. Reduced expression of TGF-beta receptors I and II compared with surrounding nontumorous tissue were noted from the early hepatocellular carcinoma stage suggesting that down-regulation of TGF-beta receptors is correlated with progression from premalignant to malignant phenotype. Reduced expression of both TGF-beta1 and TGF-beta receptor II in neoplastic hepatocytes were also significantly correlated with increased tumor size and increased proliferative activity(P < .05). These findings suggest that during hepatocarcinogenesis, the inhibitory effects of TGF-beta1 protein on hepatocellular carcinoma cells is outweighed by its effects on stromal elements, which, overall, contributes indirectly to a tumor growth stimulatory environment. Also, the growth-inhibitory effects of TGF-beta1 may have been further negated by reduced TGF-beta receptors on hepatocellular carcinoma cells.  相似文献   
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The effect of Parmidine (pyridinolcarbamate) on platelet aggregation, blood coagulation, and fibrinolysis was studied in rabbits. After direct addition of Parmidine to platelet-enriched plasma aggregation of the platelets produced by serotonin (5-HT) and adrenalin was reduced. After oral administration of Parmidine to animals, aggregation induced by ADP, 5-HT, and adrenalin was inhibited, blood coagulation was reduced, and fibrinolysis was accelerated.Laboratory of Pharmacology, S. Ordzhonikidze All-Union Pharmaceutical Chemical Research Institute. Department of Pharmacology, Therapeutic Faculty, Moscow Medical Stomatological Institute. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 3, pp. 322–324, March, 1976.  相似文献   
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Conclusions 1. Cryosurgical instruments can be divided into passive and autonomous cryoprobes and cryoprobes with delivery of the coolant from a separate reservoir. 2. To freeze easily accessible organs and tissues to a depth of 5 mm it is best to use passive cryoprobes with a copper core. 3. Autonomous cryoprobes can be used for freezing organs and tissues having a volume not more than 10–25 cm3. Cryoprobes with delivery of the coolant from a separate reservoir must be used when freezing a larger volume. Physicotechnical Institute of Low Temperatures, Academy of Sciences of the Ukrainian SSR, Kharkov. Translated from Meditsinskaya Tekhnika, No. 4, pp. 34–36, July–August, 1971.  相似文献   
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The IR spectra (in the region of 400–3600 cm?1) of comb-like polymers in crystalline, liquid-crystalline, and fluid isotropic phases were studied, and the effect of the chemical structure of the long side chains on the crystalline and liquid-crystalline states were examined. The spectroscopic criteria of phase transitions in comb-like polymers were established and the fragments of the side chains involved in the formation of the liquid-crystalline phase, were determined.  相似文献   
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Department of Anatomy and Physiology of Man and Animals, A. I. Gertsen Leningrad Pedagogic Institute. Department of Pharmacology, Academician I. P. Pavlov First Leningrad Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR A. V. Val'dman.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 106, No. 10, pp. 436–438, October, 1988.  相似文献   
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The total hepatic blood flow during the first 2 hours after resuscitation was studied by local thermodilution and obturating catheter methods in experiments on cats anesthetized with pentobarbital. Changes in the blood flow occurred in stages. The brief increase in volume velocity of perfusion immediately after resumption of cardiac contractions was replaced by a rapid fall below the control level, after which the blood flow continued to decrease gradually. Changes in the total hepatic blood flow correspond largely to changes in the minute volume of the heart. Drip infusion of dextran in doses maintaining the central venous pressure at its initial level restored the normal hepatic blood flow and arterial pressure during the period after resuscitation.  相似文献   
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