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51.
A systematic review of the neurologic literature identified 433 cases of pathologically proven multiple system atrophy over a 100-year period. Earlier case reports included patients younger in age with more frequent cerebellar involvement. Mean age of onset was 54.2 years (range 31 to 78) and survival was 6.2 years (range 0.5 to 24). Survival analysis showed a secular trend from a median duration of 4.9 years for publications between 1887 and 1970 to 6.8 years between 1991 and 1994. Older age of onset was associated with shorter survival; the hazard ratio for patients with onset after 60 years was 1.8 (95% CI 1.4 to 2.3) compared with patients between 31 and 49 years. Cerebellar features were associated with marginally increased survival (6.1 years versus 5.4 years; p = 0.04). There were no difference in survival according to gender, parkinsonian, or pyramidal features or whether the patient was classified as striatonigral degeneration or olivopontocerebellar atrophy type. These results demonstrate the poor prognosis for patients with multiple system atrophy but may be biased toward the worst cases. Future research needs to recruit more representative samples. 相似文献
52.
The kinetics of the membrane current during the anomalous or inward-going rectification of the K current in the egg cell membrane of the starfish Mediaster aequalis were analyzed by voltage clamp. The rectification has instantaneous and time-dependent components. The time-dependent increase in the K conductance for the negative voltage pulse as well as the decrease in the conductance for the positive pulse follows first-order kinetics. The steady-state conductance increases as the membrane potential becomes more negative and reaches the saturation value at about -40 mV more negative than the K equilibrium potential, V(K). The entire K conductance can be expressed by g(K).n; g g(K) represents the component for the time-independent conductance which depends on V-V(K) and [K+]o, and n is a dimensionless number (1 is greater than or equal to n is greater than or equal to 0) and determined by two rate constants which depend only on V-V(K). Cs+ does not carry any significant current through the K channel but blocks the channel at low concentration in the external medium. The blocking effect increases as the membrane potential is made more negative and the potential-dependent blocking by the external Cs+ also has instantaneous and time-dependent components. 相似文献
53.
EM Schultz JB Bicking AA Deana NP Gould TP Strobauge LS Watson EJ Cragoe 《Canadian Metallurgical Quarterly》1976,19(6):783-787
A series of [(2-nitro-1-alkenyl)aryloxy]acetic acids was synthesized and tested in dogs for saluretic and diuretic activity. A number of these compounds exhibit a high order of activity on iv or po administration; representative of these is (E)-[2,3-dichloro-4-(2-nitropropenyl)phenoxy]acetic acid (5). The most highly active compounds are qualitatively similar in action to [2,3-dichloro-4-(2-methylenebutyryl)phenoxylacetic acid (ethacrynic acid) in causing a prompt increase in the excretion of water and of sodium and chloride ions in approximately equimolar amounts but are three to five times as potent. Potassium ion excretion is increased but less markedly than sodium excretion. 相似文献
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IA Frid VI Stoliarov AI Evtiukhin MI Bernshte?n NP Fadeev 《Canadian Metallurgical Quarterly》1976,116(6):84-88
The authors report the data on changes in peripheral circulation, depending on the kind of anesthesia, the amount of operative blood loss, alterations in circulating blood volume and localization of tumor in patients with cancer of the lung, esophagus and cardia. Totally, 35 patients (15--lung cancer, 10--esophageal cancer, 10--cancer of the cardia) were explored. In 25 cases fluothane was used as the main anesthetic, in 10--neuroleptanalgesia. The state of peripheral circulation was estimated by the period semielimination of radioactive xenon-133 from the muscle depot. It was found that alterations in peripheral circulation were not dependent on tumor localization, the use of fluothane and neuroleptanalgesia is associated with similar changes in peripheral blood flow and, finely, an increased loss of blood results in more pronounced alterations in peripheral circulation. 相似文献
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NL Pushkarskaia NP Obrosova-Serova SF Shenderovich LIa Zaketel'skaia GA Galegov 《Canadian Metallurgical Quarterly》1977,(4):421-424
The sensitivity of different influenza A2 (H3N2) virus strains to rimantadine in ovo was studied. The reference strains of influenza virus A/Hong Kong/1/68, A/England/42/72, A/Scotland/840/74 as well as new epidemic strains isolated in the USSR and Mongolia in 1974-1975 antigenically related to influenza A/Port Chalmers/1/73 virus were found to be sensitive to rimantadine. 相似文献
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