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排序方式: 共有559条查询结果,搜索用时 15 毫秒
1.
Oren S Cohen Eli Vakil David Tanne Zeev Nitsan Roseline Schwartz Sharon Hassin-Baer 《Cognitive and behavioral neurology》2007,20(1):68-72
OBJECTIVES: To test a possible association between the educational level (EL), cognitive performance, and neuropsychiatric features in Parkinson disease (PD). BACKGROUND: An inverse association has been reported between EL and cognitive dysfunction in patients with senile dementia of Alzheimer type but it is yet unsettled whether education has a similar effect on cognition in PD. METHODS: Seventy-two PD patients (45 males, mean age 68.7+/-11.6 y) underwent a detailed neurologic examination, a battery of neuropsychologic tests, and questionnaires for the evaluation of psychosis, sleep disturbances, and depression. According to the number of educational years, patients were divided into 3 groups: low EL (0 to 8 y), (15 patients), intermediate EL (9 to 12 y) (28 patients), and high EL (>/=13 y) (29 patients). RESULTS: Patients with a higher EL had a better cognitive function and an association was found between the patients' EL and their scores in various neuropsychologic tests mainly those sensitive to frontal lobe dysfunction. Low education was associated with an increased risk for hallucinations and a trend for more depression, delusions, and sleep disturbances. CONCLUSIONS: The association between high educational attainment and the lower risk of cognitive dysfunction suggest that education might modulate cognitive performance in PD. 相似文献
2.
Andrea Berger Michelle Sadeh Gabriel Tzur I Avinoam Shuper Liora Kornreich Dov Inbar Ian J Cohen Shalom Michowiz Isaac Yaniv Shlomi Constantini Eli Vakil 《Journal of the International Neuropsychological Society》2005,11(4):482-487
Cerebellar involvement in motor and non-motor sequence learning was examined with serial reaction time tasks (SRT). Our sample consisted of 8 children and adolescents who had undergone surgical removal of a benign posterior fossa tumor (PFT) during childhood. None of them had undergone chemotherapy or cranial radiation therapy (CRT). Ages ranged from 1-11 years at surgery and 9-17 years at testing. The children were tested not earlier than 2.5 years after surgery (M = 5.9 years), enabling brain plasticity and recovery of functions. Their performance was compared with a matched control sample. The PFT group was not impaired in the implicit learning of sequences, as reflected in their performance in blocks with a repeated sequence, both before and after a random block. However, in the perceptual task, their performance deteriorated more than that of the control group when a random block was introduced, suggesting that it was more difficult for the patients to respond flexibly or change their response set when encountering changing task demands. These results are in line with another study by our group on task switching with the same patients. 相似文献
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Arvydas Vanagunas M.D. Pothen Jacob M.D. Nimesh Vakil M.D. 《The American journal of gastroenterology》1989,84(4):383-385
Patients with diminutive polyps in the rectum or sigmoid colon were randomized to "hot biopsy" treatment for either 1) electrocautery for 2 s (fixed duration cautery) or 2) cautery until visible necrosis of the polyp base was evident (variable duration cautery). Sigmoidoscopy was performed 4 wk after treatment to determine the adequacy of polyp eradication. In the fixed duration cautery group, 11 of 21 polyps (52%) were eradicated, compared with 12 of 14 polyps (86%) in the variable duration cautery group (p = 0.04). When analyzed according to whether or not visible necrosis was achieved (some of the polyps in the fixed duration cautery group showed necrosis with 2 s cautery), 19 of 23 polyps (83%) were eradicated when necrosis was evident, compared to 5 of 12 (42%) without necrosis (p = 0.004). We conclude that hot biopsy treatment for diminutive polyps is significantly more effective when visible necrosis is achieved during cautery. Furthermore, even with visible necrosis, there is a 17% failure rate of polyp eradication. 相似文献
6.
In inbred strains of mice, antiphosphorylcholine (PC) and anti-α1,3 dextran (DEX). antibodies
are structurally distinct from each other and have been shown to exhibit noncrossreactive
antigen binding and idiotypic specificities. However, the prototype anti-PC and
anti-DEX antibodies, TEPC15 and J558, respectively, were shown to be connected via a
common autoantiidiotypic monoclonal antibody isolated from newborn BALB/c mice. The
capacity of various monoclonal anti-PC and anti-DEX antibodies as well as the antigens PC
and DEX to modulate T15 and J558 idiotypes in BALB/c mice was tested by their administration
to newborn mice. Anti-PC antibodies of the .T15 idiotype injected into 2-4-day-old
mice, at a time when T15 anti-PC precursors develop in BALB/c mice, suppressed the anti-
PC response of these mice at 6 weeks of age. Similarly, J558 antibodies injected into 8-12-day-old mice, at a time when J558 precursors normally develop, suppressed the response to
DEX. As a further demonstration of this connectivity, the injection of J558 into 4-day-old
mice led to a down modulation of T15 idiotype, whereas both T15 and a minor idiotypeexpressing
antibody M167 when injected into 8-12-day-old mice caused a reduction in
expression of the J558 idiotype. As predicted from in vitro analysis, injection of anti-PC
antibodies of the M167 idiotype 2 to 4 days after birth enhanced the subsequent response to
PC. However, anti-PC antibodies expressing another minor M603 idiotype did not affect the
PC. response. The results parallel the in vitro enhancement of M167 antibodies but not M603
on T15 binding to antiidiotype in vitro. Similarly, anti-DEX antibodies expressing the M104E
idiotype had no detectable effects on the capacity to respond to PC or DEX or on the expression
of T15 and J558 idiotypes as adults. Exposure of newborn mice to PC led to a dramatic
reduction in the response to DEX as adults, whereas exposure to DEX at this stage of
development had no effect on response to PC as adults. Collectively, these observations provide
evidence for a complex functional connectivity between T15 and J558 idiotype-bearing B
cells during ontogeny and extend our previous observations that development of these idiotypes
is regulated by idiotype-directed interactions between B cells or their immunoglobulin
products. 相似文献
7.
Vakil N 《The Journal of stone disease》1993,5(1):39-45
Several different piezoelectric lithotripters have been under clinical investigation for gallstones in the USA. Design differences in the different shock wave generators result in different characteristics for the three devices and different peak pressures at the focus of the lithotripters. Using gallstone families, we sought to study fragmentation in the three lithotripters. A total of 56 gallstones from eight gallstone families were studied. Forty-eight stones were fragmented in three lithotripters (16 in each), Diasonics (Therasonic), EDAP (LT01), and Wolf lithotripter (Piezolith 2300), at maximum power and a rate of 2-2.5 Hz. A total of 500 shocks was applied to each stone in each of the three lithotripters. Gallstone composition was determined by infrared spectroscopy on one stone of each family (8 x 1). Initial stone weight and size were similar in all the three groups. All families consisted of cholesterol stones ( greater than 70% cholesterol). The fraction of the initial stone mass reduced to fragments less than or equal to 2 mm was not significantly different in the three lithotripters (Diasonics [n = 16] = 60 +/- 4%, EDAP [n = 16] = 53 +/- 6%, Wolf [n = 16] = 50 +/- 7%; p = 0.068).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
Wild-type (Canton-S) Drosophila melanogaster larvae are generally repelled by white light. Mutant larval photokinesis A (lphA) larvae are less strongly repelled than controls. Mutant Larval photokinesis B (LphB) larvae are unresponsive to light, as are larvae from LI2, an isofemale line whose progenitors were recently derived from a natural population. To characterize the behavior of larvae from the mutant stocks and the isofemale line more precisely, we determined the range of wavelengths that repel wild-type (Canton-S) D. melanogaster larvae and identified wavelengths to which larvae are most sensitive. In comparison to adult flies, Canton-S larvae are much less sensitive to white light and respond to a narrower range of wavelengths. The wavelengths to which Canton-S larvae are maximally sensitive are 500 nm (green), 420 nm (indigo), and 380 nm (ultraviolet). Mutant lphA larvae respond abnormally to green and indigo light but are as strongly repelled by ultraviolet light as controls. In contrast, mutant LphB larvae and larvae from the LI2 isofemale line are unresponsive to green, indigo, or ultraviolet light. Thus, lphA larvae have a wavelength-specific defect, while LphB and LI2 larvae are generally unresponsive to wavelengths that repel wild-type larvae. 相似文献
9.
10.
Effect of Helicobacter pylori eradication on development of dyspeptic and reflux disease in healthy asymptomatic subjects 总被引:2,自引:0,他引:2 下载免费PDF全文
Vaira D Vakil N Rugge M Gatta L Ricci C Menegatti M Leandro G Holton J Russo VM Miglioli M 《Gut》2003,52(11):1543-1547
BACKGROUND AND AIM: There are few data on the course of Helicobacter pylori infection in asymptomatic subjects. The aim of this study was to assess the effect of eradication therapy on the development of dyspeptic and gastro-oesophageal reflux disease in a cohort of asymptomatic individuals observed over a prolonged period. METHODS: A total of 169 blood donors infected with H pylori who had volunteered for studies on eradication in 1990 formed the cohort. To be included in this cohort subjects had to have no symptoms, as determined by a validated symptom questionnaire at the baseline visit. Eighty eight subjects were infected with H pylori while 81 had successfully undergone eradication therapy. Subjects were followed up (annually) using the same symptom questionnaire and in 2000 they underwent repeat endoscopy. RESULTS: Thirteen subjects developed symptoms during follow up. The incidence of symptoms in H pylori positive subjects was 1.893/100 person-years of follow up and in H pylori negative individuals 0.163/100 person-years of follow up. H pylori infected subjects were significantly more likely to develop symptoms (log rank test, p=0.003) as well as those infected with CagA positive strains (log rank test, p=0.017). The development of symptomatic gastro-oesophageal reflux disease was no different in individuals with and without eradication (odds ratio 0.57 (95% confidence interval 0.26-1.24); p=0.163). CONCLUSIONS: H pylori eradication prevents the development of dyspeptic symptoms and peptic ulcer disease in healthy asymptomatic blood donors and is not associated with an increase in the incidence of symptomatic gastro-oesophageal reflux disease. 相似文献