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排序方式: 共有1940条查询结果,搜索用时 31 毫秒
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Christoph Scherfler MD Johannes Schwarz MD PhD Angelo Antonini MD PhD Donald Grosset MD Francesc Valldeoriola MD PhD Kenneth Marek MD Wolfgang Oertel MD Eduardo Tolosa MD PhD Andrew J. Lees MD Werner Poewe MD 《Movement disorders》2007,22(9):1229-1238
The diagnosis of idiopathic Parkinson's disease (PD) can be achieved with high degrees of accuracy in cases with full expression of classical clinical features. However, diagnostic uncertainty remains in early disease with subtle or ambiguous signs. Functional imaging has been suggested to increase the diagnostic yield in parkinsonian syndromes with uncertain clinical classification. Loss of striatal dopamine nerve terminal function, a hallmark of neurodegenerative Parkinsonism, is strongly related to decreases of dopamine transporter (DAT) density, which can be measured by single photon emission computed tomography (SPECT). The use of DAT‐SPECT facilitates the differential diagnosis in patients with isolated tremor symptoms not fulfilling PD or essential tremor criteria, drug‐induced, psychogenic and vascular Parkinsonism as well as dementia when associated with Parkinsonism. This review addresses the value of DAT‐SPECT in early differential diagnosis, and its potential as a screening tool for subjects at risk of developing PD as well as issues around the assessment of disease progression. © 2007 Movement Disorder Society 相似文献
3.
The actions of the nonsteroidal antiinflammatory drug niflumic acid were studied on frog neuromuscular preparations by conventional electrophysiological techniques. Niflumic acid reduced the amplitude and increased the latency of endplate potentials in a concentration-dependent manner. Neuromuscular junctions pretreated with niflumic acid (0.05–0.5 mM) showed much less depression than control when they were stimulated with trains of impulses. Inhibition of acetylcholine release was reverted by raising the extracellular Ca2+ concentration but not by simply washing out the preparations with niflumic acid-free solutions. Pretreatment with indomethacin (0.1 mM), another nonsteroidal antiinflamatory drug, did not affect the niflumic acid-induced inhibition of evoked responses. Niflumic acid (0.1 mM) did not change the amplitude of miniature endplate potentials and had a dual action on the frequency of miniatures: it decreased their frequency at 0.1 mM whereas it produced an enormous increase in the rate of spontaneous discharge at 0.5 mM. Niflumic acid (0.1–1 mM) reversibly increased the amplitude and affected the kinetics of presynaptic voltage-activated K+ current and Ca2+-activated K+ current in a concentration-dependent manner. Niflumic acid (0.1–1 mM) irreversibly decreased the amplitude and reversibly affected the kinetics of the nodal Na+ current. Indomethacin (0.1 mM) had no effect on presynaptic currents. In conclusion, niflumic acid reduces acetylcholine release by increasing presynaptic K+ currents. This may shorten the depolarizing phase of the presynaptic action potential and may reduce the entry of Ca2+ with each impulse. 相似文献
4.
Teresa Sagalés Victor Gimeno M. Dolores de la Calzada Francesc Casellas M. Dolors Macià M. Villar Soriano 《Brain topography》1990,2(3):221-228
Summary Topographical analysis of cerebral electrical activity was performed in 44 patients with hepatic encephalopathy. These patients were classified in 5 groups according to clinical criteria. Eight healthy subjects were used as a control group. All were studied in an awake, eyes closed, condition and some [Control Group (CG), Group 0 (G0), Group 1 (G1) and Group 2 (G2)] also in an awake, eyes open, condition. The awake, eyes closed, maps showed marked differences in the power spectral density (PSD) of the different bands, when comparing normal subjects with patients with several degrees of hepatic encephalopathy. These differences were related to the degree of clinical involvement, mainly in the alpha and delta PSD bands. The combination of a decreased alpha PSD, increased delta PSD, and decreased mean dominant frequency (MDF) allowed a clear discrimination between the different clinical groups. The differences observed between awake, eyes closed, and awake, eyes open, conditions were especially helpful to discriminate between CG subjects and G0, G1 and G2 patients. 相似文献
5.
Daniel E. Platt Hovig Artinian Francis Mouzaya Wissam Khalil Francois G. Kamar Elizabeth Matisoo-Smith Francesc Calafell Nassim Nicolas Taleb Pierre Zalloua 《European journal of human genetics : EJHG》2021,29(4):581
Currently, there are 18 different religious communities living in Lebanon. While evolving primarily within Lebanon, these communities show a level of local isolation as demonstrated previously from their Y-haplogroup distributions. In order to trace the origins and migratory patterns that may have led to the genetic isolation and autosomal clustering in some of these communities we analyzed Y-chromosome STR and SNP sample data from 6327 individuals, in addition to whole genome autosomal sample data from 609 individuals, from Mount Lebanon and other surrounding communities. We observed Y chromosome L1b Levantine STR branching that occurred around 5000 years ago. Autosomal DNA analyses suggest that the North Lebanese Mountain Maronite community possesses an ancestral Fertile Crescent genetic component distinct from other populations in the region. We suggest that the Levantine L1b group split from the Caucasus ancestral group around 7300 years ago and migrated to the Levant. This event was distinct from the earlier expansions from the Caucasus region that contributed to the wider Levantine populations. Differential cultural adaption by populations from the North Lebanese Mountains are clearly aligned with the L1b haplotype STR haplogroup clusters, indicating pre-existing and persistent cultural barriers marked by the transmission of L1b lineages. Our findings highlight the value of uniparental haplogroups and STR haplotype data for elucidating biosocial events among these populations.Subject terms: Population genetics, Computational biology and bioinformatics 相似文献
6.
González MB Gutiérrez NC García JL Schoenmakers EF Solé F Calasanz MJ San Miguel JF Hernández JM 《Cancer Genetics and Cytogenetics》2004,150(2):136-143
Abnormalities in the long arm of chromosome 7 are a frequent chromosomal aberration in myeloid disorders. Most studies have focused on the analysis of del(7q), demonstrating the presence of several minimal deleted regions in 7q22 approximately q31. By contrast, few studies in myeloid disorders have been devoted to the analysis of translocations, either balanced or unbalanced, involving 7q. In this study, we used fluorescence in situ hybridization (FISH) to characterize the 7q31.3 approximately q34 region (markers D7S480-D7S2227) in patients with deletion or translocation of 7q. A total of 910 cases of myeloid disorders were studied by conventional cytogenetics. Fifty-eight (6%) patients had structural aberrations of 7q. FISH studies were carried out in the 27 patients with involvement of 7q31 approximately q34: 14 cases had an acute myelogenous leukemia and 13 cases had a myelodysplastic syndrome. FISH analysis revealed the existence of high complexity in the 7q31.3 approximately q34 region in patients with unbalanced translocations. No breakpoints in 7q31.3 approximately q34 were found in the cases with deletion or balanced translocation. Nevertheless, studies of unbalanced translocations showed several breakpoints in markers D7S480-D7S2227, which delineate a commonly altered region. The complexity of 7q rearrangements suggests that a synergy of different genetic factors, rather than the alteration of a single tumor suppressor gene, could be involved in the pathogenesis of del(7q) in myeloid disorders. 相似文献
7.
Josep Clotet Francesc Posas Antonio Casamayor Ine Schaaff-Gerstenschläger Joaquin Arinõ 《Current genetics》1991,19(5):339-342
Summary
S. cerevisiae gene DIS2S1, which codes for a protein very similar to the catalytic subunit of mammalian protein phosphatase 1, was disrupted in vitro. Diploid yeast cells were transformed and sporulated. Tetrad analysis demonstrated that disruption of DIS2S1 is lethal for the cell. Glycogen phosphorylase a and glycogen synthase activity ratio were measured in diploids carrying a disrupted allele of the gene. Phosphorylase was dramatically activated in mutant cells but, under the same conditions, glycogen synthase activity was essentially identical in both mutant and wild-type cells. 相似文献
8.
Zamora L Espinet B Salido M Florensa L Woessner S Pedro C Serrtano S Solé F 《Cancer Genetics and Cytogenetics》2002,134(2):165-167
We report a 89-year-old female diagnosed with chronic myelomonocytic leukemia (CMMoL) presenting with a monosomy 15. To our knowledge, this is the second reported case of CMMoL with monosomy 15. On the other hand, monosomy 15 in complex karyotypes is a frequent chromosome aberration in myelodysplastic syndromes, particularly in refractory anemia with excess of blasts. 相似文献
9.
Joven J Arcelús R Camps J Ordóñez-Llanos J Vilella E González-Sastre F Blanco-Vaca F 《Journal of molecular medicine (Berlin, Germany)》2000,78(3):147-154
Hyperhomocyst(e)inemia is an independent risk factor for atherothrombosis in several clinical settings in which renal function is impaired, but its prevalence in the nephrotic syndrome has not been investigated in detail, even though this syndrome provides an excellent model in which to study a possible link between albuminuria, proteinuria, and hyperhomocyst(e)inemia. We obtained plasma and urine from 27 patients with biopsy-confirmed membranous glomerulonephritis presenting nephrotic syndrome and 27 matched controls and determined the concentrations of homocyst(e)ine and proteins considered putative markers of glomerular and tubular function. Hyperhomocyst(e)inemia, defined as the mean +SD of the plasma homocyst(e)ine concentration of the controls [plasma homocyst(e)ine concentration >10.8 micromol/l] was present in 26% of the patients with nephrotic syndrome but in only 7.4% of the controls. Furthermore, the degree of hyperhomocyst(e)inemia was more severe in the nephrotic patients than in the controls. The existence of renal failure, tubular damage, and, interestingly, relatively well conserved glomerular function barrier were the main predictors of increased levels of plasma homocyst(e)ine. In conclusion, hyperhomocyst(e)inemia is a frequent cardiovascular risk factor present in patients with nephrotic syndrome and renal failure, but it is not directly associated with proteinuria. 相似文献
10.
Roca A Quintó L Abacassamo F Loscertales MP Gómez-Olivé FX Fenwick F Cane PA Saiz JC Toms G Alonso PL 《Journal of medical virology》2003,69(4):579-587
Serological responses have been studied in respiratory syncytial virus (RSV) infected children < 1 year of age attending the outpatient department of the Manhiça District Hospital (Mozambique). Molecular characterization of viral RNA in nasopharyngeal aspirates from the infected children indicated a high level of genetic uniformity among the infecting viruses, all of which belonged to a single genotype of RSV group A. A representative virus strain, Moz00, was isolated from one of the infants and was used, together with the group A strain A2 and the group B strain 8/60, as antigens in the quantification of infant antibody responses. In this study, 97.5% (39/40) and 96.4% (27/28) of infected children produced an antibody response against Moz00 detected by the membrane fluorescent antibody test (MFAT) and the neutralization test (NT), respectively. Seroconversion rates decreased when the A2 and 8/60 strains were used as antigen in MFAT (95.4% and 88.2%, respectively) or NT (81.8% and 54.5%, respectively), indicating that antibody responses had both group‐ and strain‐specific components. Antibodies in convalescent sera of infected children were compared with maternally derived antibodies detected in a group of children also < 1 year of age, but with no evidence of RSV infection. The convalescent sera exhibited reduced neutralizing capacity when the 8/60 strain was used as antigen (P = 0.028), suggesting that the infant antibody response lacks neutralizing capacity against strains of the heterologous virus group. Restricted cross‐reactivity and neutralizing capacity of antibodies generated by young children might be expected to induce only moderate protection in subsequent epidemics against genetically distant strains. J. Med. Virol. 69:579–587, 2003. © 2003 Wiley‐Liss, Inc. 相似文献