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991.
Au R Seshadri S Wolf PA Elias M Elias P Sullivan L Beiser A D'Agostino RB 《Experimental aging research》2004,30(4):333-358
A previous publication presented normative data on neuropsychological tests stratified by age, gender, and education based on the Original Cohort of the Framingham Heart Study. Many contemporary investigations include subject samples with higher levels of education, a factor known to affect cognitive performance. Secular change in education prompted the reexamination of norms in the children of the Original Cohort. The study population consisted of 853 men and 988 women from the Offspring Study, free of clinical neurological disease, who underwent a neuropsychological examination, which included tests given to their parents in 1974 to 1976 as well as additional newer tests to provide a more comprehensive battery. The Offspring population overall was more evenly distributed by gender and better educated. Their performance on cognitive tests was superior to that of the Original Cohort. Multivariable analyses revealed that more years of education explained only a part of the cohort differences. These findings suggest that continued surveillance of each generation is necessary to document the impact that unique social and economic variables have on cognitive function. Here, the authors provide updated normative data. 相似文献
992.
993.
The effect of thyroparathyroidectomy (TPTX) on myocardial extracellular space (ECS), water and electrolytes was studied in young, female, Sprague-Dawley rats. Eight weeks after TPTX the ventricular ECS, measured in vivo with [35S]sulfate, was found to be 0.219 ± 0.004 (g H2O/g tissue as compared to 0.177 ± 0.006 in euthyroid control rats. Measurement of ECS in the same ventricular tissue of TPTX rat by a morphometric procedure confirmed the increase: 0.209 ± 0.004 (cm3/cm3). This increase in ECS was only relative to the size of the cellular compartment, for the absolute volume of the ECS in the ventricular myocardium fell. Thus, the relative expansion of the ECS at the expense of the cellular compartment appears to be due to a greater sensitivity of the parenchyma to the inhibitory effects of hypothyroidism on growth. This finding is compatible with a decrease in cellular size of the hearts of hypothyroid rats; a compartmental shift in water from the cellular to the extracellular compartment need not be postulated. Most or all of the enlargement of ECS is due to an expansion of the interstitial compartment. No changes in tissue water content were detected. Plasma concentrations of potassium, calcium and magnesium declined, whereas the concentrations of sodium and chloride remained constant. Depending on whether the electrolytes are predominantly intracellular or extracellular, tissue electrolyte contents showed alterations appropriate to the relative changes in compartmental volumes. Assuming homogeneous distributions of the electrolytes throughout the ECS, the calculated cellular concentrations slightly increased for sodium and potassium, decreased for magnesium, and remained unchanged for calcium and chloride. 相似文献
994.
Liver dysfunction in Pennsylvania's multitransfused hemophiliacs 总被引:1,自引:0,他引:1
Dr. Ute Hasiba MD M. Elaine Eyster MD Frances M. Gill MD Mehdi Kajani MD Jessica H. Lewis MD Charles J. Lusch MD David Prager MD Samuel A. Rice MD Sandor S. Shapiro MD 《Digestive diseases and sciences》1980,25(10):776-782
Transaminase values [alanine amino transferase (ALT) and aspartate amino transferase (AST)] and markers for hepatitis B were serially determined in 558 hemophiliacs exposed to blood products. Hepatitis B surface antigen (HBsAg) persistent for over 12 months was present in 6% of the patients. Antibody to hepatitis B surface antigen (anti-HBs) was noted in 90% of the 259 patients treated with factor VIII or IX concentrates but in only 49% of the 43 patients treated with fresh frozen plasma (FFP) or cryoprecipitate. Persistently abnormal transaminase values were noted in 31% of the patients treated with commercial concentrates but in only one (2%) of the patients exposed to cryoprecipitate or FFP. This difference continued even when the two groups of patients were matched for the amount of blood products, up to 50, 000 units, which they had received in the study period. In the concentrate-treated patients, no correlation could be found between transaminase values and the number of units of factor VIII or IX they had received during the six years of the study (1973–1978).Supported in part by the Pennsylvania Hemophilia Centers and the Pennsylvania State-Wide Hemophilia Program. 相似文献
995.
996.
Brito EM Camacho-Lobato L Paoletti V Gideon M Katz PO Castell DO 《The American journal of gastroenterology》2003,98(1):40-45
OBJECTIVE: Nutcracker esophagus (NE) is defined as the presence of peristaltic contractions in which the average distal esophageal amplitude is greater than 180 mm Hg. The underlying mechanism responsible for these abnormalities is not known. The aim of this study was to test the hypothesis that NE might be caused by a defect in the inhibitory pathway controlling esophageal peristalsis. METHODS: Eight patients with NE (seven women, 1 man, mean age 50 yr) and eight age- and sex-matched normal volunteers (seven women, 1 man, mean age 48 yr) underwent a special protocol using three-channel (3, 8, and 16 cm above the lower esophageal sphincter) solid state esophageal manometry to evaluate deglutitive inhibition. Ten pairs of 5 ml of wet swallows were given at each of five different time intervals (30, 20, 15, 10, and 5 s). Pairs of swallows were spaced by 30 s, and different time intervals were spaced by 1 min. Tracings were recorded using a computer program and blindly automatically analyzed for both amplitude and duration of the contraction separately for the first and second swallow of each pair. Presence of deglutitive inhibition or muscle refractoriness was assessed according to interactions between the first and second swallow of the pair. Results were found abnormal when larger than the mean percent variation of the second and first swallow calculated for the 30-s interval, considered as baseline for each participant. Statistics included paired and nonpaired nonparametrical comparisons as appropriate. RESULTS: The median amplitude for the NE was 202 mm Hg (range 186-376) and for the controls was 118 mm Hg (range 64-167) (p = 0.0002). The median duration in the NE group was 5.1 s (range 4-9.3) versus 4.1 (range 3.3-5.0) for the controls (p = 0.02). The percent variation in duration (p = 0.31), amplitude (p = 0.42), and propagation velocity of the peristaltic waves (p = 0.69) did not differ between the control and NE groups. Peristalsis frequency dropped at the 5-s interval for both studied groups (p = 0.84). CONCLUSION: Central and local inhibitory mechanisms induced by closely timed swallows are preserved in the NE and do not explain the mechanism of the high amplitude and long duration contractions. 相似文献
997.
Singh SN Singh BN Reda DJ Fye CL Ezekowitz MD Fletcher RD Sharma SC Atwood JE Jacobson AK Lewis HD Antman EM Falk RH Lopez B Tang XC 《The American journal of cardiology》2003,92(4):468-472
The Sotalol-Amiodarone Fibrillation Efficacy Trial (SAFE-T) is a randomized, double-blind, multicenter, placebo-controlled trial in which the effects of sotalol and amiodarone in maintaining stability of sinus rhythm are being examined in patients with persistent atrial fibrillation at 20 Veterans Affairs medical centers. The time to the occurrence of atrial fibrillation or flutter in patients with atrial fibrillation converted to sinus rhythm is the primary outcome measure, with a number of parameters as secondary end points. SAFE-T had randomized 665 patients when enrollment terminated on October 31, 2001. Follow-up of patients continued until October 31, 2002, for a maximum period of 54 months and a minimum period of 12 months for all patients. 相似文献
998.
999.