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991.
Magaña M Herrera-Goepfert R 《Journal of the American Academy of Dermatology》2002,47(3):454; author reply 454-454; author reply 455
992.
993.
The term hypomelanosis of Ito (HI) is applied to individuals with skin hypopigmentation following the lines of Blaschko (type 1a of patterns indicative of somatic mosaicism as defined by Happle). Even though originally described as a purely cutaneous disease, subsequent reports of HI have included a 30-94% association with multiple extracutaneous manifestations. The frequency of extracutaneous associations has led many authors to consider HI to be neurocutaneous disorder. We report a male infant with cutaneous hypomelanosis along the lines of Blaschko distributed on the left half of the body who developed status epilepticus. Neuroimaging studies disclosed an angiomatous enlargement of the right choroid plexus and a gyral pattern of cortical and subcortical calcification in the right occipital region. Thus a diagnosis could be made of HI and associated Sturge-Weber syndrome-like leptomeningeal angiomatosis. This previously unreported association lends further support to the consideration of hypomelanosis of Ito as a marker of somatic mosaicism with frequently associated neurologic abnormalities. A relationship between HI and Sturge-Weber syndrome, two neuroectodermal disorders with a genetic mosaicism basis, might be possible due to nonallelic twin-spotting which in the embryologic period would define an abnormal development of neural, vascular, and cutaneous structures. 相似文献
994.
Alvarez-Lafuente R Martín-Estefanía C de las Heras V Castrillo C Cour I Picazo JJ Varela De Seijas E Arroyo R 《Acta neurologica Scandinavica》2002,105(2):95-99
OBJECTIVES: The aim of this study is to determine the DNA prevalence of different members of Herpesviridae in multiple sclerosis (MS) patients and to describe the possible effect of beta-interferon treatment on such prevalence. MATERIAL AND METHODS: With a nested polymerase chain reaction (PCR) assay we have studied the DNA of the peripheral blood mononuclear cells (PBMCs) of 204 whole blood samples, [102 from patients with relapsing-remitting MS (RRMS), of which 62 were treated with beta-interferon, and 102 from healthy blood donors]. RESULTS: We only found a statistically significant difference for human herpesvirus type 6 (HHV-6) DNA prevalence (P < 0.0001): HHV-6 is 2.26 times more frequent in MS patients than in healthy donors. There was no difference in the HHV-6 prevalence between beta-interferon treated and untreated patients. CONCLUSION: 1. Among the herpesviruses, HHV-6 was the only one showing altered prevalence. This either indicates that HHV-6 is involved in the pathogenesis of MS, or it simply indicates that MS influences latency or reactivation of HHV-6 without any direct involvement of HHV-6 in the disease process of MS. 2. Treatment with beta-interferon does not make a difference on the DNA prevalence of the herpesviruses studied in our MS patients. 相似文献
995.
Penadés R Boget T Lomeña F Mateos JJ Catalán R Gastó C Salamero M 《Acta psychiatrica Scandinavica》2002,105(3):202-208
OBJECTIVE: The effects of neuropsychological treatment on cognitive hypofrontality were examined in schizophrenic patients through the score activation. METHOD: Eight subjects (six men and two women) with persistent negative symptoms and cognitive impairments were evaluated with single photon emission computed tomography (SPECT) procedures and neuropsychological battery before and after a neuropsychological treatment group. RESULTS: After treatment an enhancement in neuropsychological performance was found, especially in executive functions. The activation score showed an increase over baseline levels and no cognitive-dependent hypofrontality after treatment was found. Although the prefrontal blood flow changes were small and non-specific, they suggest a reduction of the cognitive hypofrontality after neuropsychological treatment. CONCLUSION: Cognitive improvements after neuropsychological treatment would possibly be related with the diminution of the functional hypoactivity in the prefrontal areas. 相似文献
996.
Izquierdo G Angulo S Garcia-Moreno JM Gamero MA Navarro G Gata JM Ruiz-Peña JL Páramo MD 《Acta neurologica Scandinavica》2002,105(3):158-163
OBJECTIVES: We study the power of IgG synthesis value as a marker of disease activity in multiple sclerosis (MS). MATERIAL AND METHODS: Link index was calculated in 202 MS patients. Time between first, second and third attack and progression index (PI) were compared in patient with normal (NLI) high (HL) or very high Link index (VHLI). RESULTS: Secondary progressive (SP) patients had a higher LI than relapsing-remitting (RR) and primary progressive (PP) courses (1.10 +/- 0.5 for SP vs 0.86 +/- 0.5 for RR and 0.81 +/- 0.5 for PP, P=0.01 and 0.03, respectively). Having a HLI in MS RR and SP patients has no time effect in the development of the second and third attack. PI was higher in patients with VHIL (0.67 +/- 0.7) vs patients with NLI (0.42 +/- 0.4, P=0.008) and with HLI (0.39 +/- 0.3, P=0.001). CONCLUSIONS: This study confirmed that LI is a good marker of subsequent progression of MS. 相似文献
997.
Valença MM 《Arquivos de neuro-psiquiatria》2002,60(1):181; author reply 182
998.
Persistence of the neuromodulatory effects of adenosine on synaptic transmission after long-term potentiation and long-term depression 总被引:4,自引:0,他引:4
Adenosine modulates long-term potentiation (LTP) and long-term depression (LTD) in the hippocampus. We tested whether induction of LTP or LTD might reciprocally modify the role of adenosine as an inhibitory modulator of synaptic transmission in the hippocampus. The experiments were performed on hippocampal slices of the rat. Two separate sets of the Schaffer pathway were alternately stimulated. Evoked field excitatory postsynaptic potentials (fEPSPs) were recorded extracellularly from CA1 stratum radiatum. Long-term potentiation (LTP) was induced by high-frequency stimulation and long-term depression (LTD) by low-frequency stimulation. The inhibitory effects of the adenosine analogue, 2-chloroadenosine (CADO, 0.1-5 microM), on the fEPSP slope were similar in both pathways (EC(50)=0.72 (95% confidence intervals: 0.50-1.1) microM and EC(50)=0.84 (0.55-1.3) microM, n=6). After induction of LTP in the test pathway, a second concentration-response curve was obtained. CADO was significantly less potent as compared to the first concentration-response curve, however the inhibitory effects of CADO were still similar in the potentiated pathway (EC(50)=2.2 (1.6-3.1) microM) and in the control pathway (EC(50)=2.1 (1.5-3.0) microM, n=6). The inhibitory effects of CADO (0.1-5 microM) were also not significantly different in the pathway where LTD was previously induced (EC(50)=1.7 (1.5-2.0) microM), compared to the control non-depressed pathway (EC(50)=1.7 (1.4-2.0) microM, n=6). In conclusion, the neuromodulatory action of adenosine seems to be maintained in the presence of substantial variations in long-term synaptic efficiency during LTP or LTD. 相似文献
999.
Mejía-Aranguré JM Beutelspacher-Vázquez O Juárez-Ocaña S Vázquez-Langle J Martínez-García Mdel C Fajardo-Gutiérrez A 《Salud pública de México》2002,44(2):100-107
OBJECTIVE: To evaluate the incidence trends of hepatic tumors among children living in Mexico City. MATERIAL AND METHODS: A cross-sectional hospital survey was conducted to yield two databases. The first database contains the registry of all the cases of hepatic tumors occurring during the period 1982-1991, in public hospitals of Mexico City. The second database contains all hepatic tumor cases found between 1996 and 1999 in Hospital de Pediatría del Centro Médico Nacional "Siglo XXI" and in Hospital General del Centro Médico La Raza, both hospitals pertaining to Instituto Mexicano del Seguro Social (Mexican Institute of Social Security). The average annual incidence rates (AAIR) were calculated for each type of hepatic tumor. The rates were standardized with the direct method, using as standard the world population under 15 years of age. The trends were evaluated with the annual incidence rates and the average rate of change assuming a Poisson distribution. RESULTS: The AAIR for hepatoblastoma during the period 1982-1991 was three times higher for men than for women, with a value of 0.6 x 10(6). The group of 1-4 years of age was the most affected. For hepatocarcinomas the AAIR was two-fold for women (0.14) as compared to men. Between 1996-1999 the AAIR for hepatoblastoma was 5.11 in women and 1.85 in men. The age group with the highest rate was women under one year of age. The AAIR for hepatocarcinoma was 0.64 for males and 1.23 for females. The most affected age group was males aged 10 to 14 years. No significant upward or downward trend was found in the incidence of hepatoblastomas. A non-significant change rate of 10% was found for hepatocarcinoma. CONCLUSIONS: No significant trends were observed in the incidence of hepatic tumors in children of Mexico City aged under 15 years, during the periods 1982-1991 and 1996-1999. The English version of this paper is available at: http://www.insp.mx/salud/index.html. 相似文献
1000.
Bilbao-Garay J Barba R Losa-García JE Martín H García de Casasola G Castilla V González-Anglada I Espinosa A Guijarro C 《European Journal of Internal Medicine》2002,13(4):240-245
BACKGROUND: Involuntary weight loss (IWL) is a frequent complaint with a difficult diagnosis. Any one of a number of different diseases may be the source of the symptom. However, there is no universal clinical protocol that can help physicians study this complex syndrome. METHODS: In March 1998, we defined a diagnostic protocol for the study of IWL. IWL was defined as an involuntary and documented weight loss of at least 5% of the usual body weight in the previous 3 months. We analyzed 78 consecutive patients with IWL who came to our clinic between March 1998 and December 2000. RESULTS: An organic disease was found in 56% of cases; cancer, metabolic and digestive diseases were the most common entities. Psychiatric problems were found in 33% of cases. After extensive study, an idiopathic group of 11% was identified. The variables that were independently predictive of a final diagnosis of organic disease were: age>50 years (OR: 8.6, CI 95%: 1.7-43.6), psychiatric symptoms (OR: 0.2, CI 95%: 0.1-0.8), smoking (OR: 14.3, CI 95% 2.3-74), the presence of guide symptoms (OR: 8.0, CI 95%: 1.8-34.4), and anemia (OR: 3.1, CI 95%: 2.5-387). Sixteen percent of the patients died, more often those suffering from organic diseases. Based on multivariate regression coefficients, a clinical risk score was established. CONCLUSIONS: IWL is a complex and frequent syndrome with a 16% rate of mortality during the first year. A protocol based on clinical data can help in the management of IWL. Our clinical prediction rule may help physicians to identify those patients with IWL who are likely to have an underlying organic disease. 相似文献