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71.
GM1 ganglioside is believed to be important in promoting the recovery of neurons from injury. The present study assesses the ability of GM1 to repair or prevent the damage of dopamine neurons caused by the neurotoxin 1-methyl-4-phenylpyridinium (MPP+). Treatment of mesencephalic cell cultures with 2.5 μM MPP+ resulted in the loss of 30% of tyrosine hydoxylase (TH) immunoreactive neurons. In contrast, cultures administered 100 μM GM1 ganglioside for 3 days after toxin treatment contained nearly control numbers of TH+ neurons (97%). This reparative effect of GM1 was reflected in parallel increases in TH enzyme activity, dopamine and dopac levels. Cultures sustaining greater insult from higher doses of MPP+ (5.0–10.0 μM) did not benefit from ganglioside treatment, suggesting that rescue by GM1 depended on the degree of initial damage to cells. Moreover, the timing of ganglioside treatment was critical; pretreatment with GM1 alone did not prevent or attenuate the damage caused by subsequent incubation in 2.5 μM MPP+. 相似文献
72.
The natural history of idiopathic scoliosis has been studied between 1969 and 1985 in a well-controlled population of school children, 66,200 cases, between 7 and 16 years of age. The incidence of scoliosis needing treatment (25 degrees or more in progress in growing children) was studied with a cross-sectional as well as a longitudinal survey. When using a cross-sectional technique, a decrease of cases being treated was seen after the introduction of a conventional screening program--thus indicating a change in the natural history of moderate scoliosis. This could, however, be explained by the consequence of an accumulation of treated cases, formerly diagnosed and treated later on, seen immediately after the introduction of screening. When the longitudinal method was used, this trend could not be observed. And finally, when taking changes of indication of treatment and of the population into consideration, no tendency at all toward a change in the natural history could be seen. 相似文献
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74.
A crescentic osteotomy of the first metatarsal is unstable during the preliminary healing stage. The authors present a modification in the direction of the cut of the osteotomy. This alteration increases stability at the first metatarsal base. 相似文献
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76.
J W Montgomery 《Pediatric clinics of North America》1992,39(3):513-524
The population of individuals with LLD make up a heterogeneous group. The identification of individuals with LLD may vary depending on the type(s) and adequacy of the tests used. Assessment protocols for evaluating the language functioning of older school-aged and adolescent individuals are few and far between. This state of affairs necessitates speech-language pathologists to begin to develop a variety of informal tools to assess the higher level (and perhaps more subtle) language abilities of these individuals. Because language functioning entails the convergence of a variety of cognitive and linguistic processes, these informal protocols must be informed by the developmental literature so as to take into account both language-specific (e.g., lexical knowledge, syntactic structure, semantic complexity) and general cognitive processes. Careful task and process analyses must be done to characterize the language performance of any individual. 相似文献
77.
78.
Nancy I Thomas Norman DePaul Brown Linda C Hodges Jay Gandy Louanne Lawson Janet E Lord David K Williams 《AAOHN journal》2006,54(1):24-31
The Central Arkansas Veterans Healthcare System (CAVHS) spends $1 million annually on occupational illnesses and injuries. To address the problem of injuries among hospital employees, a retrospective case-control study was conducted to examine select risk factors for work-related injuries (WRI) among CAVHS employees. Study methods included a review of employee health charts and computer and manual databases from 1997 to 2002 (N = 2,050). The researchers found that WRI increased with age; WRI occurred more often in women than in men; WRI was greater among maintenance and custodial staff compared to direct caregivers, and less among clerical staff; WRI occurred less often in part-time than full-time staff; and WRI increased with increasing body mass index. Developing standards, guidelines, and policies for preplacement screening, preventive measures, training, and education may help to minimize WRI and associated costs. 相似文献
79.
Background
Late stage cancer malignancies may result in severe skeletal muscle wasting, fatigue and reduced quality of life. Resistance training may attenuate these derangements in cancer patients, but how this hypertrophic response relates to normal muscle adaptations in healthy subjects is unknown. Here, we determined the effect of resistance training on muscle mass and myosin heavy chain (MHC) isoform composition in plantaris muscles from tumor-bearing (TB) rats. 相似文献80.