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81.
82.
Prostate specific antigen predicts the long-term risk of prostate enlargement: results from the Baltimore Longitudinal Study of Aging 总被引:2,自引:0,他引:2
Wright EJ Fang J Metter EJ Partin AW Landis P Chan D Carter H 《The Journal of urology》2002,167(6):2484-2487
PURPOSE: Prostate specific antigen (PSA) is a predictor of prostate growth in men with lower urinary tract symptoms. The long-term risk of prostate enlargement as a function of PSA among community dwelling volunteers is unknown. MATERIALS AND METHODS: A Cox proportional hazards regression model was used to study the relationship between baseline PSA level at ages 40 to 49.9 years in 194 men, 50 to 59.9 in 191 and 60 to 69.9 in 144, and prostate enlargement, defined as a prostate volume larger than the 75th percentile for age decade, as measured by magnetic resonance imaging in a longitudinal study of aging (Baltimore Longitudinal Study of Aging, National Institute on Aging). Kaplan-Meier survival analysis was performed to estimate the probability of freedom from prostate enlargement with time as a function of baseline PSA level. RESULTS: The relative risk of prostate enlargement was 3- to 6-fold higher for men 40 to 49.9 years old with a baseline PSA of 0.31 ng./ml. or more compared to men with PSA levels of 0.30 ng./ml. or less at baseline. The relative risk was increased 5- to 9-fold in men 50 to 59.9 years old and 11-fold in those 60 to 69.9 years old when comparing men with PSA greater than 0.80 ng./ml. and greater than 1.70 ng./ml. with those with PSA 0.50 or less. The cumulative probability of freedom from prostate enlargement at 20 years was 0.89 (95% confidence interval ([CI] 0.79-0.99) and 0.63 (0.52-0.74) for men 40 to 49.9 years old with PSA levels below and above 0.30 ng./ml., respectively. For men 50 to 59.9 years old the 10-year probability of freedom from prostate enlargement was 0.90 (95% CI 0.84-0.96) and 0.59 (0.43-0.74) when PSA levels were below and above 0.80 ng./ml., respectively. At age 60 to 69.9 years the 10-year probability of freedom from prostate enlargement was 0.83 (95% CI 0.72-0.93) and 0.27 (0.09 to 0.48) when PSA levels were below and above 1.70 ng./ml., respectively. CONCLUSIONS: These data demonstrate the long-term risk of prostate enlargement by PSA level. Risk stratification based on PSA level may be useful to identify men at greatest risk for adverse events due to prostate enlargement and selection of men for future benign prostatic hyperplasia studies. 相似文献
83.
Blattman SB Landis GS Knight M Panetta TF Sclafani SJ Burack JH 《The Annals of thoracic surgery》2002,74(1):237-239
Endovascular therapy affords the opportunity to decrease surgical morbidity and improve operative planning in complex penetrating injuries of the chest. In this case report we describe a hemodynamically stable patient with a single gunshot wound to the base of the neck (zone I), with combined vascular and tracheal injuries. We present a novel approach to the repair of this type of injury using combined endovascular and open techniques. 相似文献
84.
Motion blindness (MB) or akinetopsia is the selective disturbance of visual motion perception while other features of the visual scene such as colour and shape are normally perceived. Chronic and transient forms of MB are characterized by a global deficit of direction discrimination (pandirectional), which is generally assumed to result from damage to, or interference with, the motion complex MT+/V5. However, the most characteristic feature of primate MT-neurons is not their motion specificity, but their preference for one direction of motion (direction specificity). Here, we report that focal electrical stimulation in the human posterior temporal lobe selectively impaired the perception of motion in one direction while the perception of motion in other directions was completely normal (unidirectional MB). In addition, the direction of MB was found to depend on the brain area stimulated. It is argued that direction specificity for visual motion is not only represented at the single neuron level, but also in much larger cortical units. 相似文献
85.
Pegna AJ Caldara-Schnetzer AS Perrig SH Lazeyras F Khateb A Mayer E Landis T Seeck M 《European neurology》2002,47(3):148-155
Quantitative MRI measurement of hippocampal sclerosis in patients suffering from temporal lobe epilepsy (TLE) have, as yet, failed to evidence any correlation between the right hippocampus and visuospatial memory. In this report, word learning and design learning tasks were carried out as well as MRI volumetric measurements of the hippocampus and amygdala in order to verify possible modality-specific correlations between function and structure. Delayed recall indices in our memory tasks provided significant results. Visuoverbal ratios differed between right and left TLE groups, as did laterality indices of hippocampal and amygdalar volumes. Furthermore, correlations were found between the left hippocampal volume and verbal memory, and between the right amygdala and visuospatial memory. We suggest that the difficulty encountered in establishing a correlation between right temporal structures and visuospatial memory could come both from the type of test employed and the structures considered. 相似文献
86.
Motor control and cerebral hemispheric specialization in highly qualified judo wrestlers 总被引:1,自引:0,他引:1
With the purpose of investigating motor and cognitive lateralization profiles associated with long-term motor training, we investigated differences in hemispheric specialization between proficient judo sportsmen and controls through the assessment of a number of handedness and footedness items including postural preferences as well as dichotic listening and lateralized visual field tests. Our data show that: (1) the different handedness and footedness items did differently relate to each other within the athlete and control groups as revealed by a principle component analysis (PCA); (2) stand side correlated differently to these motor profile factors in athletes and controls; (3) athletes preferred more frequently to perform certain movements with the left hand than controls, although overall right-handed; (4) this was especially true for athletes which proved to be most proficient/skilled; and (5) in a lateralized verbal listening task and a lateralized visual field task athletes revealed enhanced right-hemispheric involvement relative to controls. Our results suggest that during motor and postural skill acquisitions (long-term judo training) lateral preferences are modified, probably due to neuroplasticity. Moreover, the present findings support the multidimensional view of handedness by Steenhuis and Bryden [Cortex 25 (1989) 289] and the notion of a right-hemispheric "praxis system" involved in skilled action routines within peripersonal space [Brain and Cognition 23 (1993) 181]. 相似文献
87.
88.
Zeiler CA Nemes S Holtz KD Landis RD Hoffman J 《The American journal of drug and alcohol abuse》2002,28(3):513-524
Differences in responses by ethnic group to The Drug Abuse Problem Assessment for Primary Care (DAPA-PC) were examined. The DAPA-PC is a self-administered (via computer), internet-based screening instrument with automatic scoring, patient profile for medical reference, and unique motivational messages. Results indicate differences between blacks and whites on responses to several items in these instruments. Differences in drug use were also found between the two ethnic groups in hair/urine results. The screening criteria for the DAPA-PC instrument appear to work for both the groups in this study. Differences in responses to alcohol and drug screening instruments by ethnic group should be taken into consideration when designing screening instruments for alcohol and/or other drug use and these instruments should be adapted for different ethnic groups, when necessary. The results of this study suggest that the DAPA-PC instrument is a useful alcohol and drug abuse screening instrument for both the blacks and whites in a primary care population. 相似文献
89.
NiX HouY YangR TangX SmithR NicholsonRC 《第二军医大学学报》2005,26(4):435-435
Corticotrophin-releasing hormone (CRH) plays a major role in mechanisms controlling human pregnancy and parturition. Gene regulation by progesterone may be a key point in the control of placental CRH production. Studies in primary placental ceils show that antagonism of progesterone activity or production by RU486 or trilostane leads to an increase in CRH promoter activity. This effect can be reversed by the addition of progesterone. Overexpression of progesterone receptor A (PRA) or glucocorticoid receptor resulted in a decrease in CRH promoter activity following progesterone treatment, whereas an increase in promoter activity was observed with overexpressed PR-B. 相似文献
90.
NiX HouY KingBR TangX ReadMA SmithR NicholsonRC 《第二军医大学学报》2005,26(4):385-385
Placental CRH plays a major role in the mechanisms controlling human pregnancy and parturition. Understanding how placental CRH production is regulated is therefore of importance. Previously we have shown that placental expression of CRH peptide and mRNA are inhibited by estrogens, in contrast to the stimulatory effects of estrogen on hypothalamic CRH production. Our current study found that in placental cells cotransfected with a CRH promoter construct and an estrogen receptor-alpha expression vector results in a differential regulation whereby 17beta estradiol (E2) decreased and the putative pure estrogen antagonist, ICI 182780, 相似文献