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81.
Elevated NMDA receptors in parkinsonian striatum. 总被引:3,自引:0,他引:3
Dopamine-glutamate interactions contribute to normal striatal function and have been implicated in neurotoxicity at nigrostriatal dopamine (DA) terminals. The present study examined the striata of idiopathic Parkinson's disease (PD) patients and age-matched controls for regional differences in the DA transporter and binding to N-methyl-D-aspartate (NMDA) receptors. [3H]Mazindol labeling of the DA transporter was reduced by 70-80% in the caudate and putamen of PD patients, with reductions being more extensive dorsally than ventrally. In contrast, L-[3H]glutamate binding to NDMA-sensitive receptors was 20-40% higher in PD cases than in controls. These findings raise the possibility that modifications occur within corticostriatal glutamate synapses of PD patients, possibly as a consequence of reduced nigrostriatal DA activity. 相似文献
82.
P Le Roux B Marshall F Toutain J-F Mary G Pinon E Briquet B Le Luyer 《Archives de pédiatrie》2004,11(8):908-915
Nosocomial infections are a preoccupation in a pediatric hospital mainly during the winter with bronchiolitis and gastroenteritis epidemics. We have examined the risk factors of nosocomial infections. MATERIAL AND METHODS: A prospective study was conducted between November, 1999 and March, 2000 in the infants units of the Le Havre hospital. We systematically listed the admissions and contacted the family after their discharge by phone. A geographic information system was implemented to display the epidemiological data; this software is able to illustrate the sectors at risk. RESULTS: During the study, 687 infants were hospitalized of whom 458 for bronchiolitis and community-acquired gastroenteritis. Mean age was 5.4 months old. No nosocomial bronchiolitis occurred. Prevalence of nosocomial gastroenteritis was 10% (68 cases including nine after discharge). Infants with nosocomial infection were younger than those with community-acquired infection (6.6 months vs. 11.2 months, P < 0.01). The mean length of stay was longer in nosocomial infection (7.7 vs. 4.1 days, P < 0.05). Among the infants with bronchiolitis, 16% have developed nosocomial intestinal infections (RR = 2.65, IC: 1.59-4.4; P < 0.01). The geographic analysis pointed the area with nosocomial risk (bedroom without water, nearness of nurse office and games room). CONCLUSION: Geographic information system is a part of the quality control system and may have some interaction effect on final decision making. Incidence of nosocomial infections showed the need for a prevention strategy in a pediatric hospital. 相似文献
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Shamir Patel Geoffrey B Marshall Robin R Gray 《Journal l'Association canadienne des radiologistes》2004,55(5):288-93; quiz 293
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88.
G. Cleary D. J. Spalton P. M. Patel P.-F. Lin J. Marshall 《Ophthalmic & physiological optics》2009,29(2):173-181
Purpose: To determine the accuracy of distance autorefractions obtained by two 'open field' devices, the Tracey Visual Function Analyzer and the Shin-Nippon NVision-K 5001, by comparison with subjective refraction.
Methods: Both eyes of 50 healthy phakic participants underwent subjective refraction. Autorefractions were then performed on undilated pupils using the Tracey and a modified Shin-Nippon autorefractor and these were repeated within 50 days. Agreement with subjective refraction was calculated for sphere, mean spherical equivalent (MSE) and cylindrical vectors J0 and J 45 . Intratest and intertest variability were also evaluated.
Results: The mean age of the participants was 37.4 years. Subjective refraction MSE ranged from −6.25 D to +3.62 D, mean −0.49 D ± 1.79 D. Bias between subjective refraction and Tracey was −0.001 D, +0.045 D, +0.017 D, and −0.015 D for sphere, MSE, J0 and J 45 respectively; these were not significant. Bias between subjective refraction and Shin-Nippon was +0.004 D, +0.033 D, +0.106 D, and −0.021 D; only the J 0 vector was significantly different ( p < 0.0001) although this difference was small. Intratest variability for Tracey was low, measured at 0.189 D for sphere and 0.178 for MSE, and for the Shin-Nippon 0.099 D and 0.086 D respectively. Tracey intertest variability revealed small, statistically significant bias for sphere and MSE (+0.071 D and +0.070 D, p = 0.011, 0.013). Shin-Nippon reproducibility showed no significant bias.
Conclusions: Autorefraction measurements captured by both the Tracey and Shin-Nippon devices agree well with subjective refraction. The Shin-Nippon shows lower intratest variability. 相似文献
Methods: Both eyes of 50 healthy phakic participants underwent subjective refraction. Autorefractions were then performed on undilated pupils using the Tracey and a modified Shin-Nippon autorefractor and these were repeated within 50 days. Agreement with subjective refraction was calculated for sphere, mean spherical equivalent (MSE) and cylindrical vectors J
Results: The mean age of the participants was 37.4 years. Subjective refraction MSE ranged from −6.25 D to +3.62 D, mean −0.49 D ± 1.79 D. Bias between subjective refraction and Tracey was −0.001 D, +0.045 D, +0.017 D, and −0.015 D for sphere, MSE, J
Conclusions: Autorefraction measurements captured by both the Tracey and Shin-Nippon devices agree well with subjective refraction. The Shin-Nippon shows lower intratest variability. 相似文献
89.
Blood pressure and retinopathy in type I diabetes 总被引:3,自引:0,他引:3
H P Chase S K Garg W E Jackson M A Thomas S Harris G Marshall M J Crews 《Ophthalmology》1990,97(2):155-159
The relationship between blood pressure and diabetic retinopathy was evaluated in 249 young subjects with type I diabetes. Although hypertension is known to be associated with an increased risk for retinopathy, the effects of high-normal blood pressure are unknown. Retinopathy (158 of 249 subjects, 63%) is considerably more common in a young diabetic population than is hypertension (7 of 249 subjects, 2%). Thus, if blood pressure is important in the etiology or progression of diabetic retinopathy, levels below the hypertensive range (less than 141/90 mmHg) must be considered. The combined effect of hypertension and high-normal blood pressure (greater than 90th percentile but less than 141/90 mmHg) was studied. Elevation in diastolic blood pressure, alone, and in combination with elevated systolic blood pressure, correlated significantly (P less than 0.03) with retinopathy. The presence of high-normal blood pressure resulted in a prospectively higher occurrence of retinopathy and of progression of preexisting retinopathy. Glycohemoglobin (HbA1) and duration of diabetes also correlated with retinopathy. Both good glycemic control and maintenance of diastolic blood pressure below the 90th percentile for age may be important in relation to diabetic retinopathy. 相似文献
90.
WW Thompson 《Transfusion》1993,33(4):333-335
This study was designed to determine the blood donation behavior and attitudes of Hispanic residents of the Lower Rio Grande Valley for the purpose of developing promotional and educational approaches to enhance levels of donor participation. Personal interviews of 545 respondents were conducted in English and Spanish using quota sampling and standard intercept techniques at lower- and middle-income supermarkets in five cities during a payday weekend. A number of research hypotheses were established to test for demographic, behavioral, and attitudinal differences that were observed in donors and nondonors using chi-square analysis and multiple discriminant analysis. After analyzing the difference between Hispanics and non-Hispanics for blood donation rates, all non-Hispanics were eliminated from analysis, and the remaining 419 Hispanics were evaluated on the basis of their donor behavior. Donation among Hispanics was most likely to be by better- educated, English-speaking, higher-job-status individuals who had participated in a blood donation drive. Donors tend to have parent(s) who were donors, and they were also more likely to carry an organ donor card. Donors were found to vary in their behaviors as well as their attitudes and beliefs. Perceptions of a lack of safety in donating, the risk of contracting acquired immune deficiency syndrome, and the financial motivation of donors were most pronounced among Hispanics, which indicated a need for improved education on these issues. 相似文献