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31.
JP Hubble KL Busenbark S Wilkinson RD Penn K Lyons WC Koller 《Canadian Metallurgical Quarterly》1996,46(4):1150-1153
We examined the effects and safety of deep brain stimulation (DBS) as a treatment for essential tremor (ET). Ten ET patients with disabling medication-refractory tremor underwent stereotactic implantation of a DBS lead in the left Vim thalamic nucleus and completed a 6-month follow-up. The Clinical Tremor Rating Scale and disability assessments were performed at baseline, 1-, 3-, and 6-month follow-up. There were significant improvements in dressing, drinking, eating, bathing, and handwriting as reported by the subjects. Tremor severity, writing, pouring, and spiral and line drawing were significantly improved as rated by the examiner. Improvements persisted through the 6-month follow-up period. Although global disability significantly lessened in the group as a whole, one subject with hand-finger tremor accentuated by writing had no change in disability status. In this 6-month open-label study, DBS was effective and safe in reducing tremor and functional disability in ET. 相似文献
32.
The formation of semiquinone free radicals of doxorubicin, epirubicin, daunorubicin, and idarubicin was measured by electron paramagnetic resonance (EPR) spectroscopy in hypoxic suspensions of chinese hamster ovary (CHO) cells. The amount of semiquinone produced was in the order idarubicin > doxorubicin > daunorubicin > epirubicin. The idarubicin semiquinone signal was both the fastest to be formed and to decay. Idarubicin, which was the most lipophilic of the anthracyclines studied, also displayed the fastest fluorescence-measured cellular uptake of drug. Thus, it was concluded that semiquinone formation was dependent upon the rate of cellular uptake. Lysed cell suspensions were also shown to be capable of producing the doxorubicin semiquinone in the presence of added NADPH. The cardioprotective agent dexrazoxane (ICRF-187) was observed to decrease the amount of doxorubicin semiquinone observed in cell suspensions. Dexrazoxane also decreased the amount of doxorubicin semiquinone observed in the NADPH-lysed cell suspension mixture. Neither bipyridine nor deferoxamine decreased NADPH-dependent doxorubicin semiquinone formation. These results suggest that dexrazoxane does not decrease doxorubicin semiquinone formation through an iron complex formed from hydrolyzed dexrazoxane. Dexrazoxane may be inhibiting an NADPH-dependent enzyme. 相似文献
33.
The evidence suggests that enrolled nurses and those working part-time and on night duty consistently attend less continuing professional education than their more senior, full-time and day duty colleagues. This was substantiated in the findings of this study which also highlighted the paucity of opportunities for continuing education among unqualified practitioners. In the light of recent developments within the health services, this inequitable provision of continuing professional education to all nursing practitioners will need to be addressed and resolved. Continuing professional education provided on an arbitrary and random basis will not afford maximum positive outcomes for clients, the service and practitioners and has the potential to increase the levels of frustration among disadvantaged groups of nursing staff. 相似文献
34.
RH Rau YL Chan HI Chuang CR Cheng KL Wong KH Wu TT Wei 《Canadian Metallurgical Quarterly》1997,35(2):113-118
While current psychiatric taxonomies recognise a classification of amphetamine dependence, derived from the notion of an alcohol dependence syndrome, little research has validated that such a condition exists for this drug. Current amphetamine users (N = 331), were interviewed using the World Health Organization operationalisation of DSM-III-R substance dependence criteria, and a measure of the psychological components of dependence. Structural analyses indicated that a unidimensional dependence syndrome as assessed by DSM-III-R and DSM-IV criteria exists for amphetamine, and that physiological, psychological and behavioural indicators were all important in accounting for the variance in responses. It was demonstrated that the concept of a dependence syndrome is applicable to amphetamine, and that the inclusion of the amphetamine dependence syndrome in DSM-III-R and DSM-IV is valid. 相似文献
35.
Effects were studied of vincamin and tanakan in 68 patients with stage I, II and III discirculatory encephalopathy (as per WHO classification 1981). In 52% of the patients atherosclerosis of brain vessels was associated with arterial hypertension (group I), in 48 per cent venous discirculatory encephalopathy was diagnosable against the background of arterial hypertension (group IIA-20%) and arterial hypotension (group IIB-26%). Both tanakan and vincamin were found to be effective in group I patients; however, in stage III condition their effectiveness was no better than 42 and 15% respectively, which fact might be due to organic changes in the vascular wall. Tanakan appeared to be more beneficial in group II patients since venous dystonia is considered to be the main pathogenetic link in this context, and tanakan is known to improve the venous outflow from the cranial cavity. Almost in one-third of group IIB patients vincamin worsened general health status, especially so in stage III discirculatory encephalopathy, which fact may be related to peculiar effect of the drug on the arterial link of brain blood supply. 相似文献
36.
37.
KL Miller 《Canadian Metallurgical Quarterly》1994,6(4):785-803
Endocrine disorders in critically ill infants and children can be the manifestation of an existing but previously unrecognized condition, or hormonal derangements precipitated by deleterious effects on endocrine function of a critical illness or its prescribed therapy. To achieve successful resolution of these crises, a general understanding of various endocrine dysfunctions, clinical symptomatology, diagnosis, and medical and nursing management is essential. 相似文献
38.
39.
Protein phosphorylation plays a central role in many biological and biomedical phenomena. In this review, while a brief overview of the occurrence and function of protein phosphorylation is given, the primary focus is on studies related to the detection and analysis of phosphorylation both in vivo and in vitro. We focus on phosphorylation of serine, threonine and tyrosine, the most commonly phosphorylated amino acids in eukaryotes. Technologies such as radiolabelling, antibody recognition, chromatographic methods (HPLC, TLC), electrophoresis, Edman sequencing and mass spectrometry are reviewed. We consider the speed, simplicity and sensitivity of tools for detection and identification of protein phosphorylation, as well as quantitation and site characterisation. The limitations of currently available methods are summarised. 相似文献
40.
KL Nicholson M Munson RB Miller TJ Filip R Fairman FM Hughson 《Canadian Metallurgical Quarterly》1998,5(9):793-802
The fusion of intracellular transport vesicles with their target membranes requires the assembly of SNARE proteins anchored in the apposed membranes. Here we use recombinant cytoplasmic domains of the yeast SNAREs involved in Golgi to plasma membrane trafficking to examine this assembly process in vitro. Binary complexes form between the target membrane SNAREs Sso1p and Sec9p; these binary complexes can subsequently bind to the vesicle SNARE Snc2p to form ternary complexes. Binary and ternary complex assembly are accompanied by large increases in alpha-helical structure, indicating that folding and complex formation are linked. Surprisingly, we find that binary complex formation is extremely slow, with a second-order rate constant of approximately 3 M(-1) s(-1). An N-terminal regulatory domain of Sso1p accounts for slow assembly, since in its absence complexes assemble 2,000-fold more rapidly. Once binary complexes form, ternary complex formation is rapid and is not affected by the presence of the regulatory domain. Our results imply that proteins that accelerate SNARE assembly in vivo act by relieving inhibition by this regulatory domain. 相似文献