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991.
The carrier rate of HBsAg is about 6% in Bhutan and 1% in Nepal. Since outbreaks of viral hepatitis are also known, its high prevalence in a migrated community, if any, maybe a potential threat to the local people. The present study was conducted in Beldangi 2 Extension Camp, a Bhutanese refugee camp located in eastern Nepal to know the HBsAg carrier rate among the refugees. With the help of semi-structured questionnaires, 500 volunteers enrolled were interviewed for the risk factors for HBV transmission. Blood samples of 467 subjects were tested for HBsAg by an immunoassay based on immunochromatographic sandwich principle. Out of 467 samples 4 were positive for HBsAg a prevalence rate of 0.9%. HBsAg carrier rate was found to be low in Bhutanese refugees. From the questionnaires it was also found that they were not engaged in any practice that could increase the chances of HBV transmission. The study shows that the Bhutanese refugees in Nepal in this geographical area are not a threat to the local people as far as HBV transmission is concerned.  相似文献   
992.
BACKGROUND AND OBJECTIVE: To describe the results of surgical treatment of peripapillary choroidal neovascularization in age-related macular degeneration as an option to both laser photocoagulation and photodynamic therapy. PATIENTS AND METHODS: Retrospective review of patients with peripapillary choroidal neovascularization secondary to age-related macular degeneration who were not eligible for or refused laser photocoagulation. Patients without the diagnosis of age-related macular degeneration and those who had extension of their neovascularization subfoveally were excluded from the review. RESULTS: Eleven patients total were identified who met the specified inclusion criteria. The male to female ratio was 4:7, with an age range of 63 to 94 years (mean = 78 years). The mean area of involved retina temporal to the optic disc was 5 clock hours, with the distance of the temporal edge of the lesion from the fovea ranging from 100 to 2,000 microm. The mean duration of follow-up was 23 months, with 27% (3 of 11) experiencing recurrent choroidal neovascularization. The preoperative and postoperative visual acuity ranges were both 20/25 to counting fingers. Sixty-four percent (7 of 11) of patients had stable or improved visual acuity postoperatively, with a mean visual acuity change of 1 line visual improvement. CONCLUSION: In cases where photodynamic therapy and laser photocoagulation are not indicated, the surgical treatment of peripapillary choroidal neovascularization secondary to age-related macular degeneration may prove beneficial.  相似文献   
993.
OBJECTIVE: We wanted to determine the time delay for maximum enhancement of the deep venous system of the lower extremities after standard CT pulmonary angiography. SUBJECTS AND METHODS: In 20 patients who had undergone standard CT pulmonary angiography, we measured arterial and venous enhancement at the level of the greater trochanter. These measurements were obtained at 30-sec intervals immediately after completion of CT pulmonary angiography. Ten measurements were obtained in 5 min. Time-density curves were plotted. RESULTS: We found that the median and average peak venous enhancements were 92 and 95 H, respectively. Time to peak enhancement was variable. Because of the broad shape of the venous time-density curve, near peak enhancement could be achieved in most patients at 2 min after CT pulmonary angiography. CONCLUSION: CT of the deep venous system of the lower extremities after standard CT pulmonary angiography, performed with appropriate timing considerations, allows near maximal enhancement of the venous system in most patients without altering the optimum CT pulmonary angiography protocol.  相似文献   
994.
OBJECTIVE: Using interictal alpha-[11C]methyl-l-tryptophan ([11C]AMT) PET scan, the authors have undertaken a quantitative analysis of all tubers visible on MRI or 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG) PET, to determine the relationship between [11C]AMT uptake and epileptic activity on EEG. BACKGROUND: Tuberous sclerosis complex (TSC) is an autosomal dominant disorder, often associated with cortical tubers and intractable epilepsy. The authors have shown previously that [11C]AMT PET scans show high tracer uptake in some epileptogenic tubers and low uptake in the remaining tubers. METHODS: Eighteen children, age 7 months to 16 years, were studied. Patients underwent video-EEG monitoring, PET scans of [11C]AMT and [18F]FDG, and T2-weighted or fluid-attenuated inversion recovery (FLAIR) MRI. [11C]AMT uptake values were measured in 258 cortical tubers delineated with coregistered MRI or [18F]FDG scans. Uptake ratios were calculated between the [11C]AMT uptake in tubers and those for normal cortex (tuber/normal cortex). Using the region of epileptiform activity, the authors performed receiver operator characteristics (ROC) analysis and determined the optimal uptake ratio for detecting presumed epileptogenic tubers. RESULTS: Tuber uptake ratios ranged from 0.6 to 2.0. Tuber uptake ratios in the epileptic lobes were higher than those in the nonepileptic lobes (p < 0.0001). All 15 patients with focal seizure activity showed one or more lesions with uptake ratio above 0.98 in the epileptic lobe. ROC analysis showed that a tuber uptake ratio of 0.98 resulted in a specificity of 0.91. CONCLUSIONS: Cortical tubers with [11C]AMT uptake greater than or equal to normal cortex are significantly related to epileptiform activity in that lobe. Together, interictal [11C]AMT PET and FLAIR MRI improve the detection of potentially epileptogenic tubers in patients with TSC being evaluated for epilepsy surgery.  相似文献   
995.
OBJECTIVE: To compare abnormalities determined in 2-deoxy-2-[18F]fluoro-D-glucose (FDG) and [11C]flumazenil (FMZ) PET images with intracranial EEG data in patients with extratemporal lobe epilepsy. BACKGROUND: Although PET studies with FDG and FMZ are being used clinically to localize epileptogenic regions in patients with refractory epilepsy, the electrophysiologic significance of the identified PET abnormalities remains poorly understood. METHODS: We studied 10 patients, mostly children (4 boys, 6 girls, aged 2 to 19 years; mean age, 11 years), who underwent FDG and FMZ PET scans, intracranial EEG monitoring, and cortical resection for intractable epilepsy. EEG electrode positions relative to the brain surface were determined from MRI image volumes. Cortical areas of abnormal glucose metabolism or FMZ binding were determined objectively based on asymmetry measures derived from homotopic cortical areas at three asymmetry thresholds. PET data were then coregistered with the MRI and overlaid on the MRI surface. A receiver operating characteristics (ROC) analysis was performed to determine the specificity and sensitivity of PET-defined abnormalities against the gold standard of intracranial EEG data. RESULTS: FMZ PET detected at least part of the seizure onset zone in all subjects, whereas FDG PET failed to detect the seizure onset region in two of 10 patients. The area under the ROC curves was higher for FMZ than FDG PET for both seizure onset (p = 0.01) and frequent interictal spiking (p = 0.04). Both FMZ and FDG PET showed poor performance for detection of rapid seizure spread (area under the ROC curve not significantly different from 0.5). CONCLUSIONS: [11C]flumazenil (FMZ) PET is significantly more sensitive than 2-deoxy-2-[18F]fluoro-D-glucose (FDG) PET for the detection of cortical regions of seizure onset and frequent spiking in patients with extratemporal lobe epilepsy, whereas both FDG and FMZ PET show low sensitivity in the detection of cortical areas of rapid seizure spread. The application of PET, in particular FMZ PET, in guiding subdural electrode placement in refractory extratemporal lobe epilepsy will enhance coverage of the epileptogenic zone.  相似文献   
996.
Pyridostigmine-induced microcephaly   总被引:1,自引:0,他引:1  
Niesen CE  Shah NS 《Neurology》2000,54(9):1873-1874
  相似文献   
997.

Background  

Genetic studies associated the CAPB locus with familial risk of brain and prostate cancers. We have identified HSPG2 (Perlecan) as a candidate gene for CAPB. Previously we have linked Perlecan to Hedgehog signaling in Drosophila. More recently, we have demonstrated the importance of Hedgehog signaling in humans for advanced prostate cancer.  相似文献   
998.
PURPOSE: To determine the microbial profile of congenital nasolacrimal duct obstruction (CNLDO) and the appropriate antimicrobial agents based on the sensitivity pattern of the isolated microorganisms. METHODS: Two hundred thirty-eight eyes of 187 young children in the age group of 0-5 years with CNLDO were included in the study. A group of 40 children (80 eyes) who had attended the hospital for other ocular disorders was considered a control. Material obtained from the lacrimal sac was cultured, and infectious agents were isolated. Susceptibility testing was done by Kirby-Bauer disk diffusion method for 7 different antibiotics. Fisher's exact test was used to look for statistical associations between the age group, the type of discharge, and the type of microorganisms isolated. RESULTS: Of the 238 samples with a clinical diagnosis of CNLDO, 197 (83%) yielded a positive culture. There was no growth in 41 samples (17%). Altogether, there were 217 isolates. One hundred twenty-four (57%) isolates were Gram-positive bacteria, the most frequent isolate being Streptococcus pneumoniae. Gram-negative bacteria accounted for 93 (43%) of the isolates, the most frequent isolate being Haemophilus influenza. There was one fungal isolate (0.5%) of Candida tropicalis. Gram-positive bacteria were sensitive to chloramphenicol, vancomycin, and ofloxacin and Gram-negative bacteria to ofloxacin and ciprofloxacin. CONCLUSIONS: Chronic dacryocystitis caused by CNLDO is associated with an almost-equal proportion of Gram-positive and Gram-negative bacteria. Ofloxacin topical drops can be used in the treatment of cases with CNLDO.  相似文献   
999.
Abstract: We present two cases of a rare form of intraductal carcinoma of the breast, "cystic hypersecretory carcinoma of the breast." The clinical and pathologic characteristics of the lesion are discussed, along with a review of the literature.  相似文献   
1000.
The objective of this article is to present the recurrence pattern of olfactory groove meningiomas after surgical resection. Four patients, one female and three males, with surgically resected olfactory groove meningiomas presented with tumor recurrence. All patients underwent resection of an olfactory groove meningioma and later presented with recurrent tumors. The mean age at initial diagnosis was 47 years. All presented initially with vision changes, anosmia, memory dysfunction, and personality changes. Three patients had a preoperative MRI scan. All patients had a craniotomy, with gross total resection achieved in three, and 90% tumor removal achieved in the fourth. Involved dura was coagulated, but not resected, in all cases. Three patients were followed with routine head CT scans postoperatively, and none was followed with MRI scan. The mean time to recurrence was 6 years. Three patients presented with recurrent visual deterioration, and one presented with symptoms of nasal obstruction. Postoperative CT scans failed to document early tumor recurrence, whereas MRI documented tumor recurrence in all patients. Tumor resection and optic nerve decompression improved vision in two patients and stabilized vision in two. Complete resection was not possible because of extensive bony involvement around the anterior clinoid and inferior to the anterior cranial fossa in all cases. Evaluation of four patients with recurrent growth of olfactory groove meningiomas showed the epicenter of recurrence to be inferior to the anterior cranial fossa, with posterior extension involving the optic canals, leading to visual deterioration. This location led to a delay in diagnosis in patients who were followed only with routine CT scans. Initial surgical procedures should include removal of involved dura and bone, and follow-up evaluation should include formal ophthalmologic evaluations and routine head MRI scans.  相似文献   
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