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排序方式: 共有2135条查询结果,搜索用时 31 毫秒
91.
Pulmonary arteriovenous malformations: cerebral ischemia and neurologic manifestations 总被引:8,自引:0,他引:8
Moussouttas M Fayad P Rosenblatt M Hashimoto M Pollak J Henderson K Ma TY White RI 《Neurology》2000,55(7):959-964
BACKGROUND: There is an increasingly recognized association between pulmonary arteriovenous malformations (PAVM) and cerebral ischemia, frequently attributed to paradoxical embolization. PAVM occur in 20 to 30% of the hereditary hemorrhagic telangiectasia (HHT) population. OBJECTIVE: To evaluate the risk determinants for cerebral ischemia and neurologic manifestations in patients with PAVM. METHODS: A retrospective cross-sectional study was performed on consecutive patients admitted between 1988 and 1992 for treatment of PAVM. The number of PAVM, feeding artery (FA) diameters, and aneurysmal sizes were determined by pulmonary angiography. Patients were categorized as having single or multiple PAVM with an FA diameter of > or = 3 mm. History, examination, and cerebral imaging studies were used to determine the prevalence of neurologic manifestations. Patients were defined as having cerebral paradoxical embolization if there was radiologic evidence of cortical infarction. RESULTS: There were 75 cases: 26 single PAVM and 49 multiple PAVM. Cortical infarction was present in 14% of patients with single PAVM. Patients with multiple PAVM had a greater prevalence of any infarction (OR 3.2; 95% CI, 1.2 to 9.44, p = 0.030), cortical infarctions (OR 2.3; 95% CI, 0.58 to 9.2, p = 0.230), subcortical infarctions (OR 2.1; 95% CI, 0.58 to 7.95, p = 0.249), abscesses (OR 2.3; 95% CI, 0.46 to 11.94; p = 0.295), and seizures (OR 6.4, 95% CI 0.77 to 53.2, p = 0.054). Patients with multiple PAVM had markedly greater odds of having any clinical or radiologic evidence of cerebral ischemic involvement (OR 4.5; 95% CI, 1.47 to 14; p = 0.008). CONCLUSION: There is a strong association between single PAVM and various neurologic manifestations. The prevalence is greater for patients with multiple PAVM, suggesting increased predisposition for paradoxical embolization with a greater number of malformations. 相似文献
92.
Effect of subthalamic nucleus stimulation on levodopa-induced dyskinesia in Parkinson's disease 总被引:10,自引:0,他引:10
Article abstract-The authors studied the effect of bilateral subthalamic nucleus stimulation on levodopa-induced dyskinesias in 24 consecutive parkinsonian patients with disabling dyskinesias. The improvement in the three subtypes of levodopa-induced dyskinesias was significant from the third postoperative month and was mainly due to the decrease in the daily dose of levodopa allowed by the stimulation-induced improvement in the motor score. 相似文献
93.
Neuropsychological changes between "off" and "on" STN or GPi stimulation in Parkinson's disease 总被引:13,自引:0,他引:13
Pillon B Ardouin C Damier P Krack P Houeto JL Klinger H Bonnet AM Pollak P Benabid AL Agid Y 《Neurology》2000,55(3):411-418
BACKGROUND: In a previous study on a consecutive series of 62 patients with PD, the authors showed that bilateral subthalamic or pallidal continuous high-frequency deep brain stimulation (DBS) affects neither memory nor executive functions 3 to 6 months after surgery. OBJECTIVE: To investigate the specific effects of DBS by comparing the performance of patients with the stimulator turned "on" and "off." METHODS: The performance of 56 patients on clinical tests of executive function was compared after 3 and 12 months of DBS of the subthalamic nucleus (STN; n = 48) or the internal globus pallidus (GPi; n = 8) with the stimulator "on" or "off." Global intellectual efficiency, verbal learning, and mood were also evaluated with the stimulator "on." The performance of another group of 20 patients was compared after 6 months of DBS of the STN (n = 15) or the GPi (n = 5) with the stimulator "on" or "off" on more experimental tests recently shown to be more sensitive to l-dopa therapy. RESULTS: When the stimulator was "on," STN patients showed a mild but significant improvement in psychomotor speed and working memory. In comparison with the presurgical state, STN patients had no cognitive deficit at 12 months, except for lexical fluency. There was no differential effect of STN or GPi stimulation. CONCLUSIONS: 1) The specific effect of DBS seems to mimic the action of l-dopa treatment in the cognitive as in the motor domain; 2) the surgery associated with DBS does not appear to affect the cognitive performance of patients with PD 12 months later, except for a mild deficit in lexical fluency. 相似文献
94.
95.
Clinical characteristics and topography of lesions in movement disorders due to thalamic lesions 总被引:3,自引:0,他引:3
Lehéricy S Grand S Pollak P Poupon F Le Bas JF Limousin P Jedynak P Marsault C Agid Y Vidailhet M 《Neurology》2001,57(6):1055-1066
OBJECTIVE: To determine which thalamic subnuclei are involved in symptomatic unilateral movement disorders due to localized thalamic infarction, and the clinical characteristics of these abnormal movements. METHODS: The authors studied 22 patients with thalamic infarcts for their clinical presentation and the topography of the lesions, using three-dimensional T1-weighted MRI sequencing and stereotaxic analysis of the lesions. RESULTS: Patients were divided into four groups: 1) absence of abnormal involuntary movements (AIM) (nine patients); 2) isolated dystonic posture (two patients); 3) myoclonic dystonia (five patients); and 4) tremor or myoclonus (six patients). In patients with AIM, thalamic lesions were contralateral to the abnormal movements, involving the thalamogeniculate territory, centered on the ventral intermediate (Vim) and ventral caudal (Vc) nuclei. No significant difference in the volumes or center of mass of the lesions was found between patients with tremor and myoclonus and patients with dystonia, although the central nucleus and the internal part of the Vim nucleus were more consistently damaged in dystonic patients. CONCLUSION: Movement disorders related to thalamic lesions included: 1) myoclonic dystonia with predominating myoclonus and "thalamic" hand associating dystonic posture and slow, pseudo-athetoid movements, both related to lesions in the Vim and Vc nuclei of the thalamus; and 2) postural and action tremor, also related to lesions in the Vim, similar to tremor associated with midbrain lesions, as a result of abnormal functioning of the cerebello-thalamic pathways. 相似文献
96.
The use of cyanoacrylate adhesives in peripheral embolization 总被引:5,自引:0,他引:5
97.
Hayde M Pollak A Bernaschek G Weiner CP Vreman HJ Stevenson DK Widness JA 《Early human development》2000,58(3):205-212
OBJECTIVE: To compare paired antepartum fetal/maternal COHb ratios in whole blood from control and alloimmunized pregnancies and to examine the relationships between fetal and maternal COHb. METHODS: COHb levels were measured in paired fetal and maternal blood samples obtained at cordocentesis in 47 control and 16 Rh-alloimmunized pregnancies. COHb was determined by gas chromatography. Results were analyzed by t-test, regression and analysis of covariance. RESULTS: Although fetal/maternal COHb ratios for control and alloimmunized pregnancies were not statistically significantly different, i.e. 1. 11+/-0.04 and 1.26+/-0.09, respectively (P=0.09), fetal COHb levels were higher in Rh-alloimmunized fetuses (P=0.0002). Fetal COHb levels were also higher than paired maternal levels among the alloimmunized group (P=0.011), but not among the control group (1. 04+/-0.04, P=ns). In univariate regression analysis, fetal and maternal COHb levels were significantly correlated with one another in both control (r=0.52, P=0.0002) and alloimmunized pregnancy groups (r=0.52, P=0.05). Comparison of the slopes of the fetal versus maternal COHb plots for the two groups showed a significant difference (P=0.02), with the alloimmunized group having the steeper slope. CONCLUSION: Differences in the antepartum fetal-maternal COHb relationships in control and alloimmunized groups likely reflect increased endogenous CO production among alloimmunized fetuses as a result of pathologic hemolysis. 相似文献
98.
Preterm infants with low immunoglobulin G levels have increased risk of neonatal sepsis but do not benefit from prophylactic immunoglobulin G 总被引:5,自引:0,他引:5
Sandberg K Fasth A Berger A Eibl M Isacson K Lischka A Pollak A Tessin I Thiringer K 《The Journal of pediatrics》2000,137(5):623-628
OBJECTIVE: In a prospective, randomized, placebo-controlled, multicenter study, we evaluated the prevention of neonatal infections with intravenous immunoglobulin G (IVIgG) prophylaxis for preterm infants (gestational age <33 weeks) with umbilical cord blood IgG levels < or =4 g/L. STUDY DESIGN: Intravenous IgG or placebo (albumin), 1 g/kg body weight, was given on days 0, 3, 7, 14, and 21 to 81 infants with umbilical cord blood IgG levels < or =4 g/L: (1) IVIgG group, n = 40, mean (SD) gestational age 27.5 (2.2) weeks and birth weight 1.06 (0.39) kg; (2) placebo group, n = 41, mean (SD) gestational age 27.7 (2.5) weeks and birth weight 1.13 (0.38) kg. Infants with umbilical cord blood IgG levels >4 g/L (n = 238) served as a separate comparison group. Neonatal infections according to European Society of Pediatric Infectious Disease criteria were monitored until 28 days of life. RESULTS: Infants with IgG levels < or =4 g/L at birth who received IVIgG had no significant reduction in infectious episodes or mortality rate when compared with those given placebo. However, infants with a serum concentration of IgG >4 g/L at birth had significantly fewer infectious episodes (culture-proven sepsis) than infants with low serum concentrations of IgG (< or =4 g/L) when compared at the same gestational ages (26 to 29 weeks, P <.003). CONCLUSIONS: Prophylactic immunotherapy with IVIgG did not improve the immune competence in preterm infants with low serum IgG concentrations at birth. We speculate that a spontaneously high serum IgG concentration at birth reflects placenta function and is an indicator of a more mature immune system capable of protecting the preterm infant against severe neonatal infections. 相似文献
99.
Population pharmacokinetics of long-term oral amiodarone therapy 总被引:5,自引:0,他引:5
BACKGROUND: Amiodarone is an increasingly popular and uniquely effective antiarrhythmic agent for which population pharmacokinetic parameters in patients receiving long-term oral therapy have not been defined previously. METHODS: We collected 605 observations of serum amiodarone and desethylamiodarone metabolite concentrations from 77 patients (mean follow-up, 2 years). Mixed-effects modeling (NONMEM) was used to determine the typical population pharmacokinetic parameters, their respective variabilities, and a simple oral dosing regimen to rapidly achieve and maintain a target concentration of 1.5 mg/L. Individual serum concentration versus time curves were simulated for the study population based on regimens outlined in the product monograph and were compared with those for the proposed dosing regimen. The relationship between the duration of amiodarone therapy and the rate of decrement in serum concentration after discontinuation was explored. RESULTS: Amiodarone concentrations were best described by a two-compartment model with the typical parameters +/- interindividual coefficients of variation (where applicable) as follows: volumes of distribution/bioavailability (V1/F = 882 L; V2/F = 12,700 L +/- 58%) and clearances/bioavailability (CL1/F = 229 L/day +/- 31%; and CL2/F = 599 L/day +/- 56%). Rapid distribution half-life was 17 hours, and terminal half-life was 55 days. A practical dosing regimen of 1600 mg/d for 2 days, 1,200 mg/d for 5 days, 1,000 mg/d for 7 days, 800 mg/d for 7 days, 600 mg/d for 7 days, and 400 mg/d for 62 days followed by a maintenance dose of 343 mg/d (400 mg/d for 6 of 7 days) is proposed. After steady state is reached, cessation of dosing produces a 25% serum concentration decrement in 3 days and 50% in 36 days. CONCLUSIONS: Population pharmacokinetics confirm that amiodarone has an extraordinarily long half-life. The slow elimination rate makes anticipating the timing of adjustments in amiodarone therapy to avoid toxicity unusually perplexing. However, based on the estimated variability, the proposed dosing regimen would produce steady-state concentrations within the therapeutic window for 90% of patients. 相似文献
100.
Perkins SN; Hursting SD; Haines DC; James SJ; Miller BJ; Phang JM 《Carcinogenesis》1997,18(5):989-994
Transgenic mice with both alleles of the p53 tumor suppressor gene product
'knocked out' by gene targeting are susceptible to early development of
tumors, chiefly lymphomas and sarcomas. Compared with the control group,
administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male
p53-deficient mice extended their lifespan by delaying death due to
neoplasms (from 105 to 166 days on study, P = 0.002), primarily by
suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P =
0.010). Treatment with a synthetic DHEA analog,
16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet
also increased lifespan, to 140 days for mice that developed tumors (P =
0.037). The effects of these steroids on lifespan and tumor development did
not appear to be strongly related to inhibition of food consumption and
weight gain, in that a group pair-fed with control diet to the reduced food
consumption of the DHEA-treated group developed and died of the same types
of neoplasms at the same rate as the controls fed ad libitum. The
chemopreventive effect of these steroids has been proposed to be due to
suppression of DNA synthesis by inhibition of glucose 6-phosphate
dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway.
Although DHEA and its analog are strong non- competitive inhibitors of this
enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide
pools in the liver, as would have been predicted. The chemopreventive
effect of DHEA in this model may be due to steroid-induced thymic atrophy
and suppression of T cell lymphoma, permitting these mice to survive long
enough to develop tumors with longer latency.
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