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991.
992.
Juvenile-onset dystonia that improves after levodopa may occur in both dopa-responsive dystonia (DRD) and juvenile parkinsonism (JP), clinically similar conditions with different prognoses and management goals. The authors show normal striatal uptake of the dopamine transporter ligand FP-CIT with SPECT in a clinically atypical case of DRD, in contrast to the reduced uptake observed in JP. 相似文献
993.
da Costa Machado MA Barbosa VA Pires MC de Castro LE Goyanna F Matos AS Vieira LC 《Arquivos de neuro-psiquiatria》2001,59(2-A):280-282
We report a casual finding of a sphenoethmoidal meningoencephaloventriculocele in an adult patient that the tomography finding was misinterpreted as an expansive neoplastic lesion with malignant features. We alert for the rare site of localization of this malformative pathology. 相似文献
994.
Glucose competence of the hepatoportal vein sensor requires the presence of an activated glucagon-like peptide-1 receptor 总被引:11,自引:0,他引:11
Activation of the hepatoportal glucose sensors by portal glucose infusion leads to increased glucose clearance and induction of hypoglycemia. Here, we investigated whether glucagon-like peptide-1 (GLP-1) could modulate the activity of these sensors. Mice were therefore infused with saline (S-mice) or glucose (P-mice) through the portal vein at a rate of 25 mg/kg. min. In P-mice, glucose clearance increased to 67.5 +/- 3.7 mg/kg. min as compared with 24.1 +/- 1.5 mg/kg. min in S-mice, and glycemia decreased from 5.0 +/- 0.1 to 3.3 +/- 0.1 mmol/l at the end of the 3-h infusion period. Coinfusion of GLP-1 with glucose into the portal vein at a rate of 5 pmol/kg. min (P-GLP-1 mice) did not increase the glucose clearance rate (57.4 +/- 5.0 ml/kg. min) and hypoglycemia (3.8 +/- 0.1 mmol/l) observed in P-mice. In contrast, coinfusion of glucose and the GLP-1 receptor antagonist exendin-(9-39) into the portal vein at a rate of 0.5 pmol/kg. min (P-Ex mice) reduced glucose clearance to 36.1 +/- 2.6 ml/kg. min and transiently increased glycemia to 9.2 +/- 0.3 mmol/l at 60 min of infusion before it returned to the fasting level (5.6 +/- 0.3 mmol/l) at 3 h. When glucose and exendin-(9-39) were infused through the portal and femoral veins, respectively, glucose clearance increased to 70.0 +/- 4.6 ml/kg. min and glycemia decreased to 3.1 +/- 0.1 mmol/l, indicating that exendin-(9-39) has an effect only when infused into the portal vein. Finally, portal vein infusion of glucose in GLP-1 receptor(-/-) mice failed to increase the glucose clearance rate (26.7 +/- 2.9 ml/kg. min). Glycemia increased to 8.5 +/- 0.5 mmol/l at 60 min and remained elevated until the end of the glucose infusion (8.2 +/- 0.4 mmol/l). Together, our data show that the GLP-1 receptor is part of the hepatoportal glucose sensor and that basal fasting levels of GLP-1 sufficiently activate the receptor to confer maximum glucose competence to the sensor. These data demonstrate an important extrapancreatic effect of GLP-1 in the control of glucose homeostasis. 相似文献
995.
The use of an artificial urinary sphincter in women with type III incontinence and a negative Marshall test 总被引:1,自引:0,他引:1
Costa P Mottet N Rabut B Thuret R Ben Naoum K Wagner L 《The Journal of urology》2001,165(4):1172-1176
PURPOSE: We evaluate the efficacy of the AMS 800 artificial urinary sphincter in women with type III incontinence. MATERIALS AND METHODS: We enrolled 207 women with genuine stress incontinence due to intrinsic sphincter deficiency. Primary inclusion criterion was a negative Marshall test. A modified surgical procedure was used to implant the AMS 800 through an abdominal approach, with placement of the cuff around the bladder neck between the periurethral fascia and vagina. Followup data were available for 206 women, including 179 with nonneurogenic and 27 with neurogenic bladders (mean followup 3.9 years). RESULTS: There were 12 (5.9%) explantations due to the prosthesis either through an erosion, extrusion or both that were necessary. The only significant risk factor for explantation was perioperative injury. This injury resulted in 8 explantations in 49 patients compared with 4 in 155 who did not have such injuries (p = 0.0016). Of the 190 patients with working devices continence was achieved in 88.7% (49 of 168) and 81.8% (18 of 22) of those with nonneurogenic and neurogenic bladders, respectively. Social continence (slight leakage but no pad use) was reported by 7.7% (13 of 168) and 9.1% (2 of 22) of patients in the nonneurogenic and neurogenic groups, respectively. The remaining patients reported leakage and pad use. CONCLUSIONS: The AMS 800 can be used successfully to treat women with genuine stress incontinence due to intrinsic sphincter deficiency. The modified surgical approach resulted in fewer perioperative injuries and, consequently, a low explantation rate. Women with genuine stress incontinence, a low urethral closure pressure and negative Marshall test indicating severe intrinsic sphincter deficiency are potential candidates for artificial urinary sphincter implantation. 相似文献
996.
Costa CH Gomes RB Silva MR Garcez LM Ramos PK Santos RS Shaw JJ David JR Maguire JH 《The Journal of infectious diseases》2000,182(3):997-1000
The failure of control programs for visceral leishmaniasis (VL) that depend on elimination of infected dogs suggests that other reservoir hosts may participate in the transmission cycle. To determine whether persons infected with Leishmania chagasi can infect the vector sand fly, laboratory-reared Lutzomyia longipalpis were allowed to feed on Brazilian subjects with active, cured, and asymptomatic VL and on asymptomatic residents of houses of persons with active VL. Of 3747 insects that had fed, 26 acquired infection from 11 of the 44 persons with active VL, but none acquired infection from the 137 asymptomatic persons. Among persons <4 years old with active VL, a history of diarrhea and higher peripheral blood neutrophil counts were independent predictors of infectivity. Further experiments using larger numbers of insects are necessary to evaluate the reservoir competence of persons with asymptomatic infections, who represent a large segment of the population of several Brazilian cities. 相似文献
997.
998.
The occurrence of human immunodeficiency virus type 1 (HIV-1) recombinant genomes belonging to different subtypes is a common event in regions where more than two subtypes cocirculate. Although there are accumulating data toward an increase in the number of intersubtype recombinants, little has been addressed about the biological behavior of such mosaic genomes. This work reports the biological characterization of engineered in vitro HIV-1 intersubtype recombinants in the gp120 region. The recombinants possess the entire gp120 of B or F Brazilian isolates in the Z6 (subtype D) backbone. Here we show that this type of recombinant structure results in profound impairment to the establishment of productive infections in CD4-positive cells. The characterization of biological properties of those recombinant viruses demonstrated viral production occurring only during a transient peak early on infection and that they are not able to down-regulate the expression of CD4 receptor on the cell surface. We also report the phenotype reversion of one recombinant virus studied here, after 62 days in culture. Two amino acid substitutions in highly constant gp120 regions (C1 and C4) were identified in the revertant virus. The mutation occurring in the C4 region is localized near two amino acid residues critical for gp120/CD4 interaction. Based on these data, we suggest that failure in CD4 down-modulation by recombinant viruses can be due to a structural dysfunction of gp160 protein unable to block CD4 at the endoplasmic reticule. The possibilities that the establishment of latent infections can be directly related to the continuous expression of CD4 on the infected cell surface and that the occurrence of mutations in amino acid nearby residues critical for gp120/CD4 interaction can restore the fully productive infectious process are discussed. 相似文献
999.
Costa S De Nuzzo M Terzano P Santini D De Simone P Bovicelli A Bovicelli L Bucchi L 《Acta obstetricia et gynecologica Scandinavica》2000,79(7):586-592
BACKGROUND: Most studies of cervical conization have considered the frequency of complications and the outcome of follow-up. The determinants of cone margin positivity have been inadequately described. In a series of CIN patients undergoing conization-equivalent electrosurgical procedure, we evaluated the factors associated with (i) any cone margin involvement, and (ii) endocervical margin involvement (with or without other locations) as contrasted with all other conditions. METHODS: Study population included 718 patients. Potential determinants of margin involvement were or were treated as categorical. Univariate analysis was based on the chi-square test. Multivariate associations were estimated by multiple logistic regression models. RESULTS: Cone margin involvement was observed in a total of 195 patients (27%). In univariate analysis, the frequency was positively related to histologic grade, time period, lesion size, and cone width and depth. In multivariate analysis, histology diagnosis and time period retained a strong association. The effect of lesion size was of borderline significance. The endocervical location emerged as a multivariate determinant of margin positivity. The effect of cone width and depth was not confirmed. Endocervical margin involvement was observed in 98 cases (14%). In univariate analysis, the frequency was positively associated with histologic grade, time period, and age, and inversely related to the visibility of the squamous-columnar junction. Multivariate analysis confirmed the strong effect of histology diagnosis and time period. The association with age and visibility of the squamous-columnar junction was weaker. CONCLUSIONS: Histology diagnosis and time period were the strongest determinants of cone margin involvement. Endocervical margin positivity was also related to patient age and visibility of the squamous-columnar junction. Cone width and depth had no protective effect. 相似文献
1000.
da Silva Dalben G Costa B Gomide MR das Neves LT 《The Journal of clinical pediatric dentistry》2000,24(3):153-158
Many dentists refuse to offer dental assistance to cleft lip and palate patients because they lack understanding about this malformation and do not want to make a professional mistake with the anesthesia. The aim of this work is to guide clinical practitioners, who want to work with these patients about the anatomical features of the cleft lip and palate area and the implications in the anesthetic procedures. 相似文献