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41.
C Beretta-Piccoli P Weidmann R de Chatel D Hirsch FC Reubi 《Canadian Metallurgical Quarterly》1977,107(4):104-115
35 patients with benign essential hypertension were treated for 6 weeks with high doses of the mineralocorticoid-antagonist spironolactone (400 mg/day), or with the "loop-diuretic" mefruside (mean maximal dose 110 mg/day). Spironolactone caused greater reductions in blood pressure and blood volume and a more marked increase in plasma renin activity (PRA) than mefruside (p less than 0.05). It appears possible that he weaker antihypertensive effect of mefruside may relate partly to its lesser influence on circulatory volume. With both diuretics, mean decreases in blood pressure were greater in patients with low pre-therapeutic PRA than in patients with normal or high PRA. However, the diuretic-induced changes in blood pressure did not correlate with the associated variations in blood volume or PRA. Thus, the increased blood pressure sensitivity to diuretics in patients with low-renin essential hypertension did not appear to be volume or renin-dependent. Under normal conditions, the maintenance of a constant blood pressure during volume depletion may partly depend on compensatory activation of the sympathetic nervous system. Moreover, patients with low-renin essential hypertension have been found to have decreased adrenergic activity. It seems possible, therefore, that the marked blood pressure sensitivity to diuretic treatment in such patients may be the result of an impaired compensatory sympathetic response to sodium and volume depletion. Analysis of the literature suggests that the diuretic furosemide, a structural relative of mefruside, may also have less blood pressure lowering efficacy in patients with essential hypertension than the distally-acting thiazides, chlorthalidone or spironolactone. Consideration of possible differences in the blood pressure reducing potential of certain diuretics thus appears to be necessary in planning the pharmacotherapy of essential hypertension. 相似文献
42.
As is readily apparent, there is not a consensus regarding the treatment of lateral ligamentous ruptures of the ankle. Certainly, the elimination of functional instability is the goal of treatment. What actually causes this is still open to debate, but from Harrington's work, it appears that degenerative changes can result from mechanical instability. We are all aware that many athletes compete actively with "two-plane" instability of the ankle, but it remains to be seen if they will also suffer the late degenerative changes that Harrington describes. In the meantime, each physician must decide which diagnostic technique to rely upon and which treatment regimen will provide the most consistent results with the least incidence of functional instability. 相似文献
43.
A progressive fibrous myopathy may result from chronic intramuscular drug abuse. This complication may mimic other rheumatic disorders and early recognition may prevent disability. The patient described here presented with fixed flexion and extension contracture of hips and knees, respectively, after abusing meperidine and other agents for 3 years. Soft tissues of thighs and buttocks were "wood hard," EMG showed absence of action potentials in affected muscles, and biopsy revealed extensive replacement of muscle with dense, acellular fibrous tissue. Possible mechanisms are discussed. 相似文献
44.
FC Sparks AG Wile KP Ramming HK Silver RW Wolk DL Morton 《Canadian Metallurgical Quarterly》1976,111(10):1057-1062
Antibody against a breast carcinoma antigen was present in patients with breast carcinoma and other cancer more often (P less than .05) than in normal women. The incidence of antibody in women with breast carcinoma correlated with the presence or absence of gross tumor, and the titer of antibody paralleled the clinical course. These results suggest importance of a host-immune response to breast carcinoma. Fifty-seven patients with stage II carcinoma of the breast were entered into a prospective randomized adjuvant chemoimmunotherapy program of cyclophosphamide, methotrexate, and fluorouracil, and BCG vaccine +/- an irradiated allogeneic tumor cell vaccine. After 24 months of study, metastases occurred in two patients (3.5%) and a new primary carcinoma developed in the contralateral breast in two others, for an overall treatment failure rate of 7%. Adjuvant chemoimmunotherapy can delay early recurrence. Long-term follow-up is needed to assess the significance of these results. 相似文献
45.
H. Von Spittler 《Zeitschrift für Jagdwissenschaft》1972,18(2):76-95
Zusammenfassung Nach kurzer referierender Darstellung einiger Anmerkungen über die Nahrungsbiologie, Vermehrungsrate und Besatzermittlung des Fuchses wird der zeitlich-räumliche Verlauf, den die Tollwut in Nordrhein-Westfalen genommen hat, aufgezeigt, wobei herausgestellt wird, daß im wesentlichen die waldreicheren Mittelgebirgslagen des Landes von ihr erfaßt worden sind. An Hand der Streckenergebnisse wird sodann erörtert, in welchem Ausmaß der Fuchsbesatz in den einzelnen betroffenen Kreisen durch die Tollwut reduziert worden ist. Es zeigt sich, daß prozentual der stärkste Rückgang in den Kreisen zu verzeichnen ist, die zuvor die höchsten Strekken aufzuweisen hatten.Sowohl bei den Hasen- als auch bei den Rebhuhnstrecken kommt es in den gleichen Jahren, in denen die Fuchsstrecken abnahmen, zu einer sprunghaften Aufwärtsentwicklung in der Mehrzahl der von der Tollwut heimgesuchten Kreise, wobei sich eine signifikante Proportionalität zwischen Rückgang des Fuchses und Zunahme von Hase und Rebhuhn erkennen läßt.Durch Gegenüberstellung der Streckenergebnisse für Fuchs, Hase und Rebhuhn aus den Kreisen Meschede, Schleiden und Dinslaken wird erläutert, daß die Zunahme der Niederwildstrecken in den Jahren nach Auftreten der Tollwut in erster Linie auf den Rückgang des Fuchses zurückzuführen ist. Günstigere Witterung vermag sich erst sekundär auszuwirken.Auf die Erfordernis einer intensiven Bejagung des Fuchses wird hingewiesen.
Summary The food biology, the reproduction rate of the fox, and the ascertainment of density are briefly presented, after which the time-space development of rabies is discussed; rabies are to be found largely in the forested, sub-alpine mountain areas of the state. As a result of the harvest, the extent to which the fox populations in specific areas are reduced by rabies is examined. It can be shown that the largest percentage decreases occur in areas where the harvest had previously been highest.In the same years that the fox harvest declined, a sudden increase in hare as well as partridge harvests were observed in the majority of rabies-infected areas; a significant correlation between the decrease in foxes and increase in hare and partridge was discerned.Comparison of the harvests of fox, hare und partridge in the districts Meschede, Schleiden and Dinslaken reveals that the increase in small game harvests in the years after the appearance of rabies is primarily a result of the decline in the number of foxes. Favorable weather conditions can have only a secondary effect.The importance of intensive hunting of foxes was emphasized.
Résumé Après un rappel bibliographique à propos de la biologie alimentaire, du taux de reproduction et de l'effectif du Renard, l'évolution dans l'espace et le temps de la Rage en Rhénanie-Westphalie est décrite. Il en ressort que ce sont les régions forestières montagneuses qui sont essentiellement concernées par cette épizootie. L'examen des tableaux du Renard permet par ailleurs de constater que la décimation de cette espèce été proportionellement la plus forte dans les districts où, avant la lutte anti-rabique, les tableauxe étaient les plus élevés.Dans la plupart des secteurs où régnait l'épidémie de Rage, les tableaux en Lièvre et en Perdrix augmentaient brusquement lorsque les tableaux en Renard commençaient à diminuer, ces deux valeurs étant en corrélation négative et significative.L'examen des tableaux du Renard, du Lièvre et de la Perdrix dans des districts de Meschede, Schleiden et Dinslaken montre clairement que l'augmentation des tableaux en petit gibier au cours des années suivant l'apparition de la Rage résulte en premier lieu de la régression du Renard et accessoirement de conditions météorologiques plus favorables.La nécessité d'une chasse intensive du Renard est soulignée.相似文献
46.
47.
G. Etzold M. Von Janta-Lipinski P. Langen 《Advanced Synthesis \u0026amp; Catalysis》1976,318(1):79-86
Nucleosides of Fluorine Carbohydrates. XV. Synthesis of Thymine Nucleosides of 6-Fluoro-D -glucopyranose and 6-Fluoro-D -galactopyranose 1-β-D -glucopyranosyl thymine 1 and 1-β-D -galactopyranosyl thymine 13 react with equimolar amounts of tosyl or mesyl chloride to give predominantly the 6′-O-sulphonyl derivatives 6 and 7 or 14 and 15 . Simultaneously small amounts of the 2′,6′-di-O-sulphonyl derivatives 4 and 5 are obtained. The tosyl derivative 6 reacts easily with alkali fluoride to give the 6′-deoxy-6′-fluoro nucleoside 10 . In contrast to the glucose series the corresponding conversion of the 6′-sulphonyloxy-galactose derivatives is difficult to achieve. The condensation of 2,3,4-tri-O-acetyl-6-O-tosyl-D -glucopyranosyl bromide 2 or 6-deoxy-6-fluoro-1,2,3,4-tetra-O-acetyl-D -galactopyranose 18 with 2,4-bis-O-trimethylsilyl thymine 3 affords, after deacetylation, 6 and 1-(6′-deoxy-6′-fluoro-β-D -galactopyranosyl)thymine 20 , respectively. 相似文献
48.
M.G. Sustersic N.V. AlmeidaA.E. Von Mengershausen S.M. Esquenoni 《International Journal of Hydrogen Energy》2012
The aim of this work is to study the electrochemical oxidation of Hydrogen on gold electrodes in sulphuric acid solution and to compare the results with those obtained in a similar study in perchloric acid solution. In both electrolytes, the reaction is irreversible because the atomic H, which appears as reaction intermediate, diffuses inside of the metal. The reactive is introduced in two ways: by electrolysis at a cathodic potential during different times and by saturating the solution with the gaseous reactive. During the cathodic electrolysis the different crystalline planes of the surface reconstruct and this feature has an influence on the reaction kinetics. The catalytic influence of the incipient hydrous gold oxide on the H electrooxidation is also shown. The presence of sulphate and perchlorate ions leads to unlike voltamperometric profiles in the double layer charging potential region. A gold compound is formed during the metal treatment and an attempt has been done to identify it with FTIR. 相似文献
49.
Ultrafiltration based purification strategies for surfactin produced by Bacillus subtilis LB5A using cassava wastewater as substrate
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50.
Scientific journals claim that correspondence sections are for post-publication peer review. We compared the conditions for
submission and the bibliometrics of letters-to-editors published in leading medical journals in 2002 and 2007 using journal-derived
information and data from PubMed and Journal Citation Reports. The median time limit for letter submissions decreased from
6 to 3.5 weeks, the median word limit from 400 to 350. The median number of letters per published article was near one in
both years. Only about half of the letters were followed by an author reply in either year. Electronic response systems were
available for four journals in 2007. 相似文献