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51.
The syndrome of parainfectious encephalomyelitis evolves from an antecedent infection. Several etiologic agents have been associated with this complication, although the pathogenesis in each instance may prove to be more uniform. Considerable evidence suggests that the syndrome is mediated immunologically. The seven cases reported here were clinically similar, although the infectious etiologies were diverse. Leptospirosis antedated the neurologic syndrome in two cases, and a "viral" illness preceded the other five cases. The evolution of the syndrome was slowly progressive in each case, and six patients had prominent involvement of rhombencephalic structures. The progressive course was reversed rapidly with eventual full recovery in each instance after initiation of corticosteroid therapy. Our experience with these cases coupled with a review of the literature suggests that corticosteroid therapy should be considered in the subacute or chronic cases of parainfectious encephalomyelitis. 相似文献
52.
A new method for evaluating antiarrhythmic drug efficacy 总被引:1,自引:0,他引:1
M Sami H Kraemer DC Harrison N Houston C Shimasaki RF DeBusk 《Canadian Metallurgical Quarterly》1980,62(6):1172-1179
To develop standards for distinguishing antiarrhythmic drug effect from spontaneous variability of premature ventricular complexes (PVCs), 21 males (mean age 56 +/- 8 years) with chronic ischemic heart disease and PVCs underwent symptom-limited treadmill exercise testing and 24-hour ambulatory monitoring before and after 2 weeks of placebo medication. Linear regression analysis was used to describe the relationship between baseline and placebo PVC frequency for various indexes of ventricular ectopic activity and to establish 95% and 99% one-tailed confidence intervals for this relationship within the group of 21 patients. The lower limit of baseline PVC frequency for which the procedure could distinguish a placebo from a true drug response, termed the "sensitivity threshold," was an average frequency of 2.2 PVCs/hour for ambulatory electrocardiographic monitoring and 1.2 PVCs/min for treadmill exercise testing. All patients exceeded the sensitivity threshold on baseline ambulatory ECGs, but only 38% of patients did so on baseline treadmill exercise tests. To establish antiarrhythmic efficacy with 95% confidence, the minimal percent reduction of PVCs between baseline and placebo visits was 68% for treadmill exercise testing and 65% for ambulatory electrocardiography. Although these standards were developed in patients with chronic ischemic heart disease, the model can be used to establish antiarrhythmic drug efficacy in any patient group. 相似文献
53.
H Villalobos ES Canales A Zárate J Soria C MacGregor 《Canadian Metallurgical Quarterly》1976,83(2):236-242
Serum levels of prolactin (PRL), FSH, LH and oestradiol-17 beta were determined by radioimmunoassay in 57 lactating women and in 20 women in whom lactation was inhibited by ergocryptine (CS-154). Women who breast fed their infants exhibited high PRL levels which abruptly declined within 48 h post-partum, and remained low for the duration of the study. Serum FSH was undetectable during the first week post-partum in lactating as well as in CB-154 treated women. Thereafter, lactating women showed increasing FSH levels which reached a maximum by the third week post-partum. These FSH values were higher in lactating women than in the CBS-154 treated group. In contrast, LH levels were higher in those women receiving CB-154. Serum oestradiol-17 beta remained in low levels throughout the study, and no difference was observed between the two groups of subjects. From these results it seems that: 1) inhibition of PRL secretion leads to a faster recovery of gonadotrophin secretion toward the "menstrual type", and 2) PRL suppression produces no effect on the ovarian oestrogen production. 相似文献
54.
Two new methods of activation were developed to graft enzymes on collegen films. They involved chemical modifications of surface groups of collagen either by Woodward's reagent "K" or by EDC, a water-soluble derivative of carbodiimide. EDC was a better coupling agent and a detailed study was conducted with this agent. It could be used either in a global method of activation and coupling, or in a two-step procedure of activation of collagen, followed by spontaneous coupling of enzyme. All enzymes tested were successfully bound: malate dehydrogenase, lactate dehydrogenase, aspartate aminotransferase, urease, creatine kinase, hexokinase. The influence on the yield of grafted enzyme, of pretreatment of films, time and temperature of EDC activation, concentration of EDC and enzyme, protecting agents was studied. Stability of enzyme activity on storage was greatly increased after grafting. A co-grafted dual system creatine kinase/heoxkinase, was achieved which exhibited a good efficiency. A striking renaturing process at 0-4degreesC after thermal denaturation, was observed with hexokinase. 相似文献
55.
56.
12月23日,由三星投影机携手神州数码联合举办“精英影像务实共赢”全国行业巡展最后一站活动在广州结束,同时,整个行业巡展活动也随之画上了一个圆满的句号。据了解,这场声势浩大的渠道推广活动在全国范围内掀起了一场有关“三星投影机”的追捧热潮,三星力推的几款机型获得了广大用户与渠道商的青睐而迅速成长为“投影明星”。 相似文献
57.
The gelatinisation temperatures, pasting characteristics and enzymic susceptibilities in the temperature range 48–72°C of normal, high amylose, low amylose and zero amylose barley starches were determined. Normal starches had the lowest gelatinisation temperatures, but low and zero amylose starches had the lowest pasting temperatures. Normal starches were the most readily soluble in water at 48–60°C in the presence of a mixture of α‐amylase, β‐amylase and limit dextrinase and were most readily broken down to reducing sugars by these enzymes. High amylose starch was the most resistant to enzymic hydrolysis in the temperature range 48–72°C and, hence, produced the lowest level of reducing sugars. 相似文献
58.
A. W. MacGregor L. G. Dushnicky S. W. Schroeder G. M. Ballance 《Journal of the Institute of Brewing》1994,100(2):85-90
Kernels of 4 barley cultivars were germinated at 18°C and samples were removed for analysis at short time intervals for the first 30 h and at longer intervals during the ensuing 90 h. α-Amylase, (1 → 3) (1 → 4)-β-glucanase and (1 → 3) β-glucanase activities were measured in each sample. Analysis of kernel sections stained with Calcofluor showed that hydrolysis of β-glucan in the crushed cell layer commenced 6–9 h after the initiation of germination. Hydrolysis proceeded from the ventral edge to the dorsal edge of the kernel. Starch granule hydrolysis followed a similar pattern in the endosperm region adjacent to the crushed cell layer, but starch hydrolysis was always preceded by β-glucan hydrolysis. 相似文献
59.
Dr. E. Ann MacGregor 《Starch - St?rke》1993,45(7):232-237
α-Amylases are known to be multidomain proteins, i.e., the molecules consist of several folding units. Each α-amylase is believed, however, to have a catalytic domain consisting, of a barrel of eight parallel α-strands surrounded by eight α-strands. with an extra helix inserted after the sixth γ-strands. The α-strands and helices alternate along the polypeptide chain and are linked together by irregular loops. Amino acid residues situated on the loops joining the C-terminal end of each α-strand to the N-terminal end of the following helix make up the active site of the enzymes. A similar structure has been found in cyclodextrin glucanotransfcrases and it is now believed that such a (α/α)8-barrel also constitutes the catalytic domain of enzymes active on α-1.6-glucosidic bonds, and of enzymes with dual specificity for both α-1.4- and α-1.6- bonds. Knowledge of the three-dimensional structure of α-amylases and cyclodextrin glucanotransferase has made possible identification of structural features important for enzymic activity and specificity. By analogy, some general conclusions are reached concerning pullulanase, isoamylase. oligo-1,6-glucosidase, neopullulanase and branching enzymes. 相似文献
60.
世界保护与展示中心将提供世界顶级的设施,以确保大英博物馆更好的为后代保管和研究藏品。[The WCEC]will provide world class facilities that will allow the British Museum to ensure the care and understanding of its collections for future generations. 背景BACKGROUND世界保护与展览中心(WCEC)是大英博物馆260年来最大的再开发项目。该中心位于布鲁姆斯伯里地块的西北角,它将设置新的主展厅、最先进的实验室和工作室、世界顶级的藏品库以及博物馆,为英国乃至全球提供藏品租赁的设施。设计面临的挑战是:既要体现时代特征和大英博物馆的国际水准,又要达到其作为一级保护建筑在遗产保护方面更为宽泛的制度和建筑要求。 相似文献