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排序方式: 共有1617条查询结果,搜索用时 15 毫秒
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Anne Pavy-Le Traon Richard L Hughson Claire Thalamas Monique Galitsky Nelly Fabre Olivier Rascol Jean-Michel Senard 《Movement disorders》2006,21(12):2122-2126
Patients with multiple system atrophy (MSA) present large changes in blood pressure (BP) due to autonomic disturbances. We analyzed how this change may influence dynamic cerebral autoregulation (DCA). Simultaneous recordings of arterial BP (Finapres) and middle cerebral artery (MCA) blood flow velocity (BFV) (transcranial Doppler) were performed in 10 patients with MSA (61 +/- 12 yr of age) and 12 healthy volunteers (61 +/- 11 yr of age): cerebral BFV response to oscillations in mean BP was studied in the supine position by cross-spectral analysis of mean BP and mean MCA BFV. The DCA was also studied during the decrease in BP the first seconds when standing up from a sitting position by the assessment of the cerebrovascular resistance index (CR; mean BP/mean MCA BFV ratio). The MCA BFV/BP cross-spectral analysis showed a phase for the mid-frequency band (0.07-0.2 Hz) significantly larger in MSA, suggesting more active autoregulation in response to larger changes in BP. Changes in CR reflecting the rate of autoregulation, when standing did not differ between the two groups. These data suggest that dynamic cerebral autoregulation is preserved in MSA. 相似文献
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Egidio L. Romano res Soyano Ramón F. Montaño Murray Ratcliffe Marilyn Olson Guillermo Suarez Nelly Martínez and Geoffrey Worstey 《Vox sanguinis》1994,66(3):194-199
Thirteen infants, 10 with A-O and 3 with B-O hemolytic disease of the newborn (ABO-HDN), were treated with synthetic A or B blood group trisaccharides (ATS, BTS) which cause dissociation of maternal antibody bound to infant red cells. The clinical outcome was compared with that of a control group of 21 infants treated with phototherapy during the preceding year. Exchange transfusion was required in 2 out of 13 infants in the experimental group and in 7 in the control group. A randomized prospective controlled study is necessary to confirm these results. 相似文献
4.
Esther Kahana Nelly Zilber Joseph H. Abramson Victor Biton Yaffa Leibowitz Oded Abramsky 《Journal of neurology》1994,241(5):341-346
The incidence and prevalence of multiple sclerosis (MS) were compared, controlling for age, in native-born Israelis of different origins and in immigrants to Israel. This comparison was carried out in two populations, countrywide and in Jerusalem. In the countrywide population, ascertainment was based mainly on hospitalizations; it included 252 patients who were native-born and 150 who had immigrated from Africa-Asia (AA immigrants). The 89 MS patients of Jerusalem also included patients diagnosed in outpatient clinics. In native-born Israelis whose father was born in Europe-America (I-EA), the incidence and prevalence of MS were found to be as high as or even higher than that found previously in immigrants from Europe-America. Among native-born Israelis whose father was born in Africa or Asia (I-AA), the yearly age-adjusted incidence and prevalence rates were found to be 1.4- to 1.8-fold higher than among AA immigrants, pointing to environmental factors. The incidence and prevalence rates in the I-EA were 1.2- to 1.6-fold higher than in the I-AA, pointing to genetic factors. These results seem to point to both environmental and genetic factors in the aetiology of MS. Further research is needed, however, to disentangle the genetic factors from possible environmental differences in the two ethnic groups. 相似文献
5.
There are many studies that are available on the Internet that attempt to standardize the assay for anticardiolipin antibody evaluation because of the variability of results. The aim of this study was to evaluate simultaneously the role of different microplates and the importance of sample nonspecific binding in determining different results in anticardiolipin antibody detection. Sera from 8 patients with raised levels of IgG anticardiolipin antibodies and 10 control sera were assayed by enzyme-linked immunosorbent assay in the presence (specific binding) or in the absence of cardiolipin (sample blank) with four different microplates, that is, NUNC PolySorp, FALCON ProBIND, Greiner 655061 (high binding), and Greiner 655001 (medium binding). Results were expressed as optical densities or net-optical densities (following sample blank subtraction) as well as international IgG anticardiolipin units (GPL) or net-GPL. A wide interplate variability of optical densities was found. When results were expressed as GPL, significant differences were only found between Greiner 655061, FALCON ProBIND, and NUNC PolySorp (P < .05 and P < .001, respectively) whereas differences were not statistically significant if interplate variability was analyzed as net-GPL. Results expressed as categorical variables (ie, positive/negative, according to a GPL cut-off and net-GPL cut-off, obtained with sera from 100 apparently healthy blood donors) showed a good or excellent Cohen's kappa coefficient of concordance among plates when positivity was evaluated on net-GPL. Our data strongly suggest that quantification and subtraction of sample blank may improve both interlaboratory agreement and reliability of anticardiolipin assay and minimize false-positive results. 相似文献
6.
F Sène Diouf A M Basse A K Ndao M Ndiaye K Touré A Thiam M M Ndiaye A G Diop I P Ndiaye 《Annales de Réadaptation et de Médecine Physique》2006,49(3):100-104
OBJECTIVE: To evaluate the functional outcome in patients followed in the department of neurology of Dakar for stroke. MATERIALS AND METHOD: Prospective longitudinal observational study from August 2003 to May 2005 included inpatients or outpatients with stroke one month or less from entry confirmed by computed tomography scan. Patients were followed monthly for 12 months. At each visit, data on functional autonomy measured by the Barthel index and the treatments received were collected. RESULTS: One hundred and seventy patients aged 25 to 90 years (mean 61+/-13 years) were evaluated. The sex ratio was 0.68. A total of 64.7% of strokes involved ischemic cerebral vascular accidents and 35.3% hemorrhagic vascular accidents. Right hemiplegia was present in 55.9%, left hemiplegia in 42.9% and bilateral paresis in 1.2% of patients. A total of 28.8% of patients died between d0 and d30, 50.6% within one year. At entry, the Barthel score was greater than 60 in only 4.7% of patients. After one-year follow-up, 58.3% of the patients had a Barthel score greater than 60, 19.1% had a score between 20 and 40 and 22.6% a score between 40 and 60. Only 53.5% received rehabilitation care. The parameters significantly associated with a functional recovery were age less than 55 years (P<0.05), hemorrhagic vascular accident as opposed to ischemic vascular accident (P<0.05), and earlier rehabilitation care under qualified personnel (P<0.01). DISCUSSION: Our study shows an important rate of mortality during the first year following stroke and the rather young age of our population. The parameters associated with a better functional recovery are comparable to most of the data in the literature. The results of our study suggest that it is possible to improve functional prognosis after stroke by setting measures of prevention of the risk factors and rehabilitation in the early management of hemiplegia. 相似文献
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OBJECTIVES: Human immunodeficiency virus type 2 (HIV-2) progression to disease is significantly slower than that of human immunodeficiency virus type 1 (HIV-1). Genetic determinants for susceptibility to disease progression were hypothesized to play a more significant role in this infection compared with HIV-1. We sought to identify common human lymphocyte antigen (HLA) alleles in the Senegalese population and to compare HLA profiles between HIV-2-infected individuals with low and high risk for disease progression. STUDY DESIGN/METHODS: We conducted a case-control study investigating possible associations between MHC class I genes and the risk of disease progression in HIV-2-infected individuals. The MHC class I genotype was molecularly defined using polymerase chain reaction with sequence specific primers (PCR-SSP) in 62 female sex workers from the Dakar, Senegal cohort. Lack of antibodies to the HIV-2 antigen p26 has been previously shown to predict disease progression and was used in this study as a surrogate marker. Twenty-one cases were identified lacking antibodies to p26, therefore at a higher risk of disease progression, and were compared with 41 p26 antibody-positive, randomly selected controls. RESULTS: Statistical analysis showed that HLA B35 was significantly associated with lack of p26 antibodies, and higher risk of disease progression ( < 0.05). The same association was found for the self-defined class I haplotypes B35-Cw4 and A23-Cw 7 ( < 0.05). The HLA B 53 allele was associated with slower disease progression; however, this association was not statistically significant. We observed a trend whereby heterozygotes were at lower risk for HIV-2 disease progression, as previously reported in HIV-1 disease. CONCLUSIONS: In this West African population, a distinct profile of HLA class I alleles was observed, and many of these appear to influence disease progression in HIV-2 infection. 相似文献
10.
Stessman J Maaravi Y Hammerman-Rozenberg R Cohen A Nemanov L Gritsenko I Gruberman N Ebstein RP 《Mechanisms of ageing and development》2005,126(2):333-339
In an exploratory study, 11 common polymorphisms were examined for contributing to longevity including: apolipoprotein E (apoE), methylenetetrahydrofolate reductase (MTHFR), cathepsin D (CAD), superoxide dismutase 2 (SOD2), angiotensinogen (AGT) and insulin-like growth factor 2 (IGF2), Leiden factor 7, p53 oncogene, dopamine D4 receptor (DRD4) and the serotonin transporter (SERT). Genotype and allele frequencies of these genes were compared in 224 older (75 years) Jewish Jerusalem residents of Ashkenazi ethnicity to a group of 441 younger subjects (22 years). Nominally significant results provide suggestive evidence in the Ashkenazi group that apoE, MHTFR, SOD2, IGF2 ApaI, and factor VII are risk factors for a single outcome, survival to 75. Overall, the more genetically homogenous Ashkenazi ethnic group showed evidence for association in five genes examined suggesting that future studies in this population would gainfully focus on this ethnic group. 相似文献