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941.
The results of mutation screening of 24 exons of LRRK2 in 60 Iranian Parkinson's Disease patients are presented. The Iranian cohort represents a novel population and was notably young (average age at onset of disease: 36.0 years). Fifty sequence variations were found, seventeen of which are novel. Variations considered possibly associated with disease were screened in available family members, 145 additional patients and 220 control individuals. It was surmised that four novel sequence variations (IVS49+178A>G, p.R1725Q, p.Q1823K, and p.D2175H) may be associated with PD status, albeit they may be very rare non-disease associated variations. The four variations were all observed in the heterozygous state in early onset cases. If one or more of the variations do indeed contribute to disease status, their penetrance is expected to be low.  相似文献   
942.
In this paper, we make contact with the field of compressive sensing and present a development and generalization of tools and results for reconstructing irregularly sampled tomographic data. In particular, we focus on denoising Spectral-Domain Optical Coherence Tomography (SDOCT) volumetric data. We take advantage of customized scanning patterns, in which, a selected number of B-scans are imaged at higher signal-to-noise ratio (SNR). We learn a sparse representation dictionary for each of these high-SNR images, and utilize such dictionaries to denoise the low-SNR B-scans. We name this method multiscale sparsity based tomographic denoising (MSBTD). We show the qualitative and quantitative superiority of the MSBTD algorithm compared to popular denoising algorithms on images from normal and age-related macular degeneration eyes of a multi-center clinical trial. We have made the corresponding data set and software freely available online.  相似文献   
943.
We apply terahertz (THz) time-domain spectroscopy for monitoring the curing process of three different light-curing dental composites. Exact knowledge of the sample thickness is required for a precise determination of the THz dielectric parameters, as the materials exhibit shrinkage when they are cured. We find very small but significant changes of the THz refractive index and absorption coefficient during stepwise light exposure. The changes in the refractive index are correlated with changes in the density of the materials. Furthermore, the refractive index and the sample thickness are found to give the most reliable result for monitoring the curing process of the dental composites.OCIS codes: (300.6495) Spectroscopy, terahertz; (170.1850) Dentistry  相似文献   
944.
INTRODUCTION: Hyperthyroid Graves' disease (GD) is a B-cell-mediated condition caused by TSH receptor antibodies (TRAb), which decline when GD remits. Anti-CD20 monoclonal antibody rituximab (RTX) induces transient B-cell depletion that may potentially modify the active inflammatory phase of thyroid-associated ophthalmopathy (TAO). METHODS: Nine patients with GD, (seven with active TAO, two with mild lid signs) were studied. The trial was only approved as an open pilot study; thus we compared the effect of RTX therapy to that of i.v. glucocorticoids (IVGC) in 20 consecutive patients. Patients were treated with RTX (1000 mg i.v. twice at 2-week interval) or with IVGC (500 mg i.v. for 16 weeks). TAO was assessed by the clinical activity score (CAS) and severity was classified using NOSPECS (No signs or symptoms; Only signs (lid); Soft tissue involvement; Proptosis, Extraocular muscle involvement; Corneal involvement; Sight loss). Thyroid function and lymphocyte count were measured by standardized methods. RESULTS: All patients attained peripheral B-cell depletion with the first RTX infusion. Minor side effects were reported in three patients. Thyroid function was not affected by RTX therapy and hyperthyroid patients required therapy with methimazole. After RTX, the changes in the levels of thyroglobulin antibodies, thyroperoxidase antibodies and TRAb were neither significant nor correlated with CD20+ depletion (P = NS). CAS values before RTX were 4.7 +/- 0.5 and decreased to 1.8 +/- 0.8 at the end of follow-up (P < 0.0001) and more significantly compared with IVGC (P < 0.05). Proptosis decreased significantly after RTX both in patients with active TAO (ANOVA; P < 0.0001) and those with lid signs (ANOVA; P < 0.003). The degree of inflammation (class 2) decreased significantly in response to RTX (ANOVA; P < 0.001). Relapse of active TAO was not observed in patients treated with RTX, but occurred in 10% of those treated with IVGC, who also experienced adverse effects more frequently (45 vs 33% of patients). CONCLUSIONS: RTX positively affects the clinical course of TAO, independently of either thyroid function or circulating antithyroid antibodies, including TRAb. If our findings are confirmed in large controlled studies, RTX may represent a useful therapeutic tool in patients with active TAO.  相似文献   
945.
Invasive fungal rhinosinusitis (IFR) is a life-threatening infection. Its onset is subtle and a late diagnosis leads to severe complications. Death may occur within a few weeks notwithstanding treatment. We describe a comprehensive pre- and post-operative approach to care for haematological patients with IFR. Five haematological patients with IFR were treated with systemic antifungal therapy and endoscopic surgical debridement of infected tissues, followed by amphotericin-B directly instilled in the sinuses by a new type of ethmoidal drainage. The IFR remitted in all cases; after 32 months of follow-up, three patients are still alive, and two have died of other causes. Two of the patients who experienced IFR progression to the brain at the IFR onset are still alive. The pharmacological and surgical approach with the post-operative local therapy by a new ethmoidal drainage system could support radical antifungal sinus treatment, thus improving the overall survival.  相似文献   
946.
Objective: To determine the frequency of celiac disease (CD) in children with failure to thrive (FTT) and/ or persistent diarrhea (PD) not responding to conventional therapy. Design: Cross-sectional study. Place and Duration of Study: Gastroenterology Unit of Sindh Institute of Urology and Transplantation (SIUT), from January 2002 to January 2004. Patients and Methods: Forty nine children and adolescents with PD (defined as diarrhea greater than 14 days duration) and / or FTT (based on anthropometrical indicators, i.e. weight for length below the 5th centile) were included in the study. Demographic data, weaning practices, breast feeding and family history of CD were documented. Laboratory workup included tissue transglutaminase antibody IgA (tTGA), IgA and IgG antigliadin antibodies (IgA AGA and IgG AGA), HLA typing, upper gastrointestinal endoscopy (EGD) with distal duodenal biopsy (where allowed by parents) and anthropometric data. CD diagnosis was in accordance with the "Guidelines for the diagnosis of and treatment of CD for children" by NASPGHAN. Mann-Whitney U-test, Chi-square test and Fisher's exact test were used for analysis as applicable. Results: Forty nine patients (25 [51%] males) with FTT and or PD were included. The mean (+/-SD) age, height, weight and BMI were: 10.1+/-6.2 years (range, 1-20 years), 107.0 +/- 31.7 cm (45-180 cm), 19.04 +/- 12.5 kg (3-68 kg) and 16.12+/-12.58 kg/cm2 respectively. FTT was present in 30 (61%) patients. Thirty four (69%) children had a history of PD, 38 (77%) had a significant history of weight loss and 32 (65%) children had short stature. Majority of the children (88%) were breast fed. Weaning was started at 6 months of age in 40% and included mixed diet according to age. Protuberant abdomen was present in 26 (53%). Elevated tTGA was significantly (p < 0.001) more frequent in patients with CD. HLA-DQ2 and DQ8 haplotypes were positive in 18 (60%) of these patients. Thirty (61%) patients were positive for CD based on Marsh criteria. CD diagnosis was supported by positive tTGA and/ or AGA tests. Majority i.e. 28/30 patients had Marsh stage 3 disease, while 22/30 patients with CD also had PD. Four CD patients were found to suffer from protein calorie malnutrition (PCM). Conclusion: Children who fail to thrive with or without PD may have CD. A positive tTGA test in these children is a useful aid in making a CD diagnosis. Majority of CD positive children were found to carry HLA DQ2 or DQ8 genes. Thus, HLA typing could be used to determine genetic disposition to CD. Majority of FTT had Marsh stage 3 changes on histopathology.  相似文献   
947.
948.

Purpose

The aim of the study was to evaluate the efficacy and safety of urethral hydrodistension for management of urethral hypoplasia in prune belly syndrome (PBS).

Methods

During a 10-year period, 7 infants with PBS and urethral hypoplasia presented either with open urachus or surgically created urinary diversion referred to our hospital. Five milliliters of normal saline was pushed via a 22-gauge plastic angiocatheter into the urethra with simultaneous finger pressure on the perineum to occlude the proximal urethra that was repeated with higher volumes of the solution (up to 20 mL). The procedure was continued until a 6F or 8F feeding tube catheter confirmed the urethral patency. Hydrodistension was repeated in 3-month intervals till complete patency was confirmed by imaging.

Results

Median age of the infants was 6 (1-8) months. All urethral hydrodistension were successful after 1 to 3 sessions. Follow-up imaging studies showed significant improvement in all patients except one. Natural and surgically created urinary diversions were closed in 6 infants.

Conclusions

The hydrodistension create an equal and constant pressure into the urethral wall without any urethral damage. This technique can be considered along with the other available methods for management of urethral hypoplasia in selected cases of PBS.  相似文献   
949.
Firstly, essential developmental aspects of the focused periods of life, namely childhood and adolescence, are discussed. Furthermore, different issues of overweight and obesity in childhood and adolescence are highlighted. Besides the definition and the assessment, possibilities of classification and epidemiological aspects are of interest. Physical and psychiatric consequences, which can be associated with obesity are also presented. In the context of a model of multifactorial genesis of obesity, different causing and maintaining factors are described. In addition to genetic and biological risk factors, the significance of several psychosocial factors is illustrated. Finally, the focus is on the therapy of obesity in childhood and adolescence.  相似文献   
950.

Purpose  

The aim of the study was to assess the connectivity between magnetoencephalographic (MEG) dipoles in the temporal lobe and Rolandic region in children with temporal lobe epilepsy using diffusion tensor imaging (DTI) tractography.  相似文献   
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