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41.
The purpose of this study was to examine motor learning and retention given extensive practice in two fundamentally different movement sequences. One sequence was a memory-driven task (performing a series of whole body positions from memory) and the other a context-driven task (buttoning). Practice took place over 3 weeks, with performance measured weekly; retention was measured weekly for 3 weeks after practice. There were 7 people with Parkinson's disease (PD) and 7 age-matched neurologically healthy people who participated in this study. Both groups improved performance on both tasks with practice, with the majority of the change for the PD group occurring between 1 and 2 weeks of practice. Although those with PD did not necessarily perform as well as age-matched controls, they learned both sequences in a manner similar to age-matched controls, and exhibited retention across the 3-week retention interval. If people with PD are given sufficient practice they can learn and retain both memory-based and context-driven movement sequences as well as age-matched controls. The results provide support for maintaining physical activity and for intervention through movement therapy. 相似文献
42.
Objective: Permeability of basement membrane and all other barriers contains a term for membrane thickness (Δx). This naturally leads to development of methods for measuring Δx that are imprecise, inaccurate, expensive, subject to preparation artifact, and inattentive to variability. Although height and shape of permeability (P) vs. probe radius (α) curves are sensitive to Δx, ln(P) or ln(P/free diffusivity or Do) curves have shapes independent of Δx. It should, thus, be possible using such characteristics to determine fiber radius (rf) and void volume ratio (ε) without Δx. We developed such a method to derive membrane structure by the standard model of Ogston and present its experimental evaluation. Methods: Basement membranes were self-assembled using 1: 1 Matrigel: 0.01 M Tris/150 mM NaCl/1.0 mM CaCl2 buffer on 0.4-μ polycarbonate supports with transport measured in diffusion chambers using FITC-labeled hydroxyethyl starch probes from 25 to 102 Å in radius. Sampling was at 0.5 hr and then for each hour up to 5. Other membranes were measured 7 days after formation. Results: The best fit of the new technique occurred at 3 hr with R2 = 0.949 ± 0.003 SEM, rf = 36.8 ± 2.4 Å, and ε = 0.87 ± 0.02. Membranes studied for 7 days showed more variability but essentially the same characteristics. Conclusions: Membrane thickness is not necessary to reduce permeability of basement membrane to structure, and optimum sampling time is 3 hr. 相似文献
43.
The experiment investigated the effects in healthy volunteers of a single dose of temazepam (30 mg, oral) on effortful and automatic processing, by measuring memory for information and its context. Effortful processing was impaired, as shown by significant impairments in free recall of an 18-item list, but automatic processing was spared, as evidenced by no impairments in recall of the frequency of presentation, the colour, size or form of the items. In a second task, temazepam significantly impaired both recognition and recency memory of 30 items, although these scores were not correlated. Temazepam caused significant sedation, measured by an objective test and by subjective ratings, but this did not correlate with the memory impairments. The pattern of results is discussed with reference to the hypothesis that the memory impairments resulting from benzodiazepines are due to a reduction in information processing resources and thus affect effortful processing more than automatic processing. 相似文献
44.
45.
施弋红 《安徽卫生职业技术学院学报》2003,2(5):47-48
目的:探讨西脉镍钛形状记忆合金环抱器用于骨折内固定术有关的护理配合问题。方法:12例不同部位骨折病人(其中男性8例、女性4例、年龄15~62岁)采用西脉镍钛(TiNi)形状记忆合金环抱器人实施内固定手术,观察术中护理配合要点和实际效果。结果:骨折复位满意,手术持续时间<2h。所有病人术后均无感染迹象,手术切口愈合良好。结论:围术期护理配合质量(如器械选择、塑形准备、无菌操作等)的优劣,是手术成功与否的重要因素之一。 相似文献
46.
An 8-year longitudinal study of elderly people has provided data concerning age-associated impairment (AAMI). In 1985 a random sample of 146 persons aged 65 years or more, living in their own homes, were assessed using the Guild Memory Test the Mini–Mental State Examination (MMSE) and other ratings. After excluding 21% of the sample because they scored less than 24 on the MMSE, and another 34% who fulfilled other exclusion criteria, some 48% of the remainder (22% of the total sample) clearly fulfilled NIMH criteria for AAMI and a further 36% (16% of the total sample) were recorded as forgetful. The NIMH criteria are appropriate for certain research purposes but not in assessing prevalence of memory disorders. Follow–up interviews were conducted after 2, 4, 6 and 8 years. The mortality rate and development of dementia among those fulfilling criteria for AAMI appeared similar to the other non-demented groups of subjects; the mortality rate of those with MMSE scores below 24 was significantly higher. Guild test results at 2-yearly intervals showed considerable changes; half of those scoring least well who were retested showed improvement. 相似文献
47.
The effects of moclobemide, a new selective and reversible MAO-A inhibitor, on cognitive function and psychomotor performance were measured in 12 healthy elderly male volunteers (with a mean age of 72.5 years). Subjects received moclobemide 200 mg, amitriptyline (positive internal control) 25 mg or placebo twice daily and were assessed on a battery of psychometric tests on the mornings following the first (acute) day and seventh (sub-chronic) day. The tests were: Choice Reaction Time; Tracking; Critical Flicker Fusion Threshold; Memory Scanning; Continuous Attention Task; the Leeds Sleep Evaluation Questionnaire and a Visual Line Analogue Rating Scale. The results show that amitriptyline produced impairment of cognitive and psychomotor functions. Moclobemide, however, did not disrupt sleep or cause daytime sedation, and remained neutral in the assessment of behavioural toxicity. 相似文献
48.
E. Wallenböck T. Diethart M. Plecko B. Fuchs 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1994,379(2):76-79
Zusammenfassung Den Vorteilen einer osteosynthetischen Versorgung einer Fraktur mit sofortiger Aufnahme seiner Funktion, stehen die aus der Literatur bekannten Komplikationen gegenüber. Diese und unsere eigenen unbefriedigenden Ergebnisse nach der operativen Versorgung von Radiusköpfchenfrakturen ließen uns zu einer prospektiven randomisierten Studie einer primär funktionellen Behandlung unter Verzicht auf eine äußere oder innere Stabilisierung greifen. Seit Dezember 1991 haben wir im UKH-Graz bis einschließlich Dezember 1992 insgesamt 70 Patienten nach einem strikten Behandlungskonzept, unter Zuhilfenahme der Computertomographie zur Verlaufsbeobachtung versorgt. Die in 91% der Fälle als sehr gut and gut einzustufenden Frühergebnisse sowie das fehlende Auftreten einer, wie bei operativer Versorgung möglichen Komplikation, ebenso die zusätzlich deutlich frühere Arbeitsfähigkeit bzw. deutlich kürzere, wenn auch aufwendigere Behandlungszeit, lassen uns diese Verfahren nicht nur in unserem Hans weiterführen, sondern können wir auch weiter empfehlen.
Experience with internal fixation of fractures of the head of the radius
The advantages of internal fixation of fractures, with the possibility of immediate resumption of the function of the fractured bone, are in contrast to the well-known complications described in the literature. These complications and our own unsatisfactory results after surgical treatment of fractures of the head of the radius induced us to carry out a randomized prospective study of primary functional treatment of such fractures without external or internal stabilization. From December 1991 through December 1992, a total of 70 patients were treated according to a strict treatment protocol at the Graz Hospital for Accident Surgery, and CT was used for observation of the healing process. The positive early results, which in 91% of all cases were classified as very good or good, the lack of complications that sometimes follow surgical treatment, the markedly earlier recovery of the patient's working capacity, and the clearly shorter — albeit somewhat more expensive — treatment period required have led us to continue using this method at our hospital and also to recommend its use elsewhere.相似文献
49.
BACKGROUND: Modulation of the acoustic startle response by aversive sensory stimulation is a simple and objective indicator of emotionality in rodents and human beings that has been extremely valuable for the analysis of neural systems associated with fear and anxiety. We have described a paradigm for measuring fear-potentiated, whole-body acoustic startle in nonhuman primates and have developed a protocol for maintaining fear-potentiated startle over repeated sessions with minimal extinction to allow measurement of pharmacological effects on fear-potentiated startle by using within-subjects designs in relatively small groups of monkeys. METHODS: A novel, within-subjects testing protocol was used to examine the effects of three compounds in rhesus monkeys that have anxiolytic effects in rodents on fear-potentiated startle but that differ in their mechanism of action. Spontaneous vocalizations during testing also were recorded. Juvenile monkeys that were trained to associate a visual stimulus with a fear-inducing air blast to the face were tested after acute administration of different doses of buspirone diazepam, morphine, or vehicle. RESULTS: Monkeys rapidly developed a robust and persistent elevation of startle response in the presence of the CS during repeated testing sessions. Diazepam and morphine produced dose-related reductions of fear-potentiated startle. Buspirone did not significantly reduce fear-potentiated startle at the doses tested, although a trend was evident at the highest dose. All drugs reduced rates of coo vocalizations during startle testing. CONCLUSIONS: These fear-potentiated startle results suggest that rhesus monkeys have a pharmacological profile with respect to these compounds that is closer to humans than to rats. This demonstrates the value of examining the effects of drugs on fear-potentiated startle in nonhuman primates. 相似文献
50.
目的 探讨外固定支架治疗桡骨远端爆裂性骨折的效果.方法 对23例桡骨远端爆裂性骨折病例,ⅣB型13例,ⅣC型10例,采用外固定支架或外固定支架加克氏针治疗.术后随诊并评价疗效。结果 23例随诊6~18个月,优15例,良6例,优良率94.7%。影像学评分,20例优良,3例发生再移位。结论 桡骨远端爆裂骨折采用手法整复外固定架或外固定架加克氏针固定能获得理想的解剖复位和腕关节功能恢复。 相似文献