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991.
Plasmapheresis on a continuous blood flow fractionator to remove 1,200-2,000 ml plasma and substitute for the same values of dextran solutions was employed in the multi-modality treatment of 25 patients with Functional Classes II-IV exertional angina and myocardial infarction. Plasma and thrombocyte hemostatic parameters were examined just before and 24 and 48 hours after plasmapheresis. The analysis of the baseline data revealed that hemostatic changes were directly related to the severity of a disease in the patients and there was a correlation between the increased platelet aggregability and the elevated levels of fibrin-monomeric complexes. Plasmapheresis along with substitution of removed plasma for dextran solutions was accompanied by a profound hypocoagulative effect, as evidenced by plasma and thrombocyte hemostatic parameters. In addition, in patients with baseline high values of platelet aggregability plasmapheresis resulted in its decrease, whereas in those with baseline low values, it led to its increase.  相似文献   
992.
Cutaneous aspergillosis is generally associated with immunosuppression, burns, and major trauma. Most cases are acquired by direct inoculation, although cutaneous involvement does occasionally occur with disseminated disease. Surgical wound infections caused by Aspergillus species are very unusual and to our knowledge have not been described in the setting of organ transplantation. We describe two liver transplant recipients who developed wound aspergillosis during a nosocomial outbreak of Aspergillus infection. Infection developed in the second and fourth postoperative week respectively, and in both cases wound appearance mimicked necrotizing fasciitis. Both patients died despite local debridement and antifungal therapy with amphotericin B. Aspergillus must be added to the list of potential pathogens of surgical wounds, especially in the setting of organ transplantation.  相似文献   
993.
In this paper, we address the problem of stable tracking control of a flexible macro-micro manipulator (M(3)) system. A two-layer neural network is utilized to approximate the nonlinear robot dynamic behavior of the M(3) system, and the controllers for the macro and micro arms are developed without any need for prior knowledge of the dynamic model of the controlled M(3) system. A learning algorithm for the neural network using Lyapunov stability theory is derived. It is shown that both the tracking error and the weight-tuning error are uniformly ultimately bounded under this new control scheme. Simulation results are presented and compared to those obtained using a PD controller.  相似文献   
994.
995.
In the time course of 15-day stress of moderate intensity, rat experiments indicated that following a day there developed a complex of changes typical of acute stressor syndrome. Five days of post-stress , the stress-related cardiac syndrome ceased, bradycardia developed, the contractile function was limited, and the fibrillation threshold returned to the control values, which was shown to be associated with activation of the cholinergic stress-limiting system. Fifteen days later there was normalization of heart rate and cardiac contractility, the fibrillation threshold remained at the baseline level.  相似文献   
996.
The results of a study of a new synthetic drug dimephosphon used as a pathogenetic means in the treatment of experimental tuberculosis are presented. Dimephosphon was found to be responsible for both the in vivo and in vitro decrease of the degree of MBT resistance to rifampicin. The findings of macroscopic, histologic and bacteriologic examinations demonstrated a significant increase in the effectiveness of antituberculous therapy. Dimephosphon monotherapy in mice elicited manifested stimulation of peritoneal macrophages: increase in O2- production, and decline in extracellular 5-nucleotidase activity. Nemolysine-synthetic cellular splenic activity in mice rose essentially. No direct stimulating influence of dimephosphon on functional macrophage activity in vitro was found.  相似文献   
997.
998.
The expression of alpha melanocyte stimulating hormone (MSH) has been investigated in two variants of the B16 murine melanoma. The presence of MSH was demonstrated by immunohistochemical methods using anti-MSH antibodies. The low metastasis variant B16-F1, which grows as an encapsulated non-invasive tumour, showed no alpha-MSH immunoreactivity. In contrast, the high metastasis variant BL6 was found to be alpha-MSH positive and the immunoreactivity was found predominantly in the peripheral invading zones of the tumour.  相似文献   
999.
The authors undertook comparative study of the Na, K-ATPase activity in the red cells, ghost corpuscles, and in the cortex and medulla of kidneys of rats with experimental glomerulonephritis (GN) induced by injection of nephrotoxic serum (NTS), during an acute course of the process (1 and 2 weeks after NTS injection) and in chronic affection of the kidneys (10 weeks after NTS injection). The activity of the enzyme both in the red cells and in the ghost corpuscles was reduced significantly, by 28 and 22%, respectively, in the acute period of the disease (one week after NTS injection) but was restored to normal values in the period of chronic affection of the kidneys. The activity of the enzyme did not change in the cortex during the whole period of the study, but in the medulla it diminished in the acute period of the disease and remained reduced (by 27% on the average) during the chronic phase. It is concluded that reduction of the enzyme activity in the studied objects was not caused by the presence of endogenous inhibitors of the enzyme. It is suggested that reduction of Na, K-ATPase activity in the renal medulla may be one of the factors of increase of Na and water excretion in the urine in the chronic phase of GN.  相似文献   
1000.
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