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41.
PURPOSE: To report the multifocal electroretinographic findings of a patient with pancreatitis-associated Purtscher-like retinopathy. DESIGN: Observational case report. METHODS: A 20-year-old man with a history of alcohol abuse and acute pancreatitis underwent multifocal electroretinography (mfERG; 103-scaled hexagons, 8-minute recording time) at 1 week, 4 weeks, and 6 months after the onset of the retinopathy. RESULTS: At 1 week, the patient had extensive cotton- wool spots in the posterior pole bilaterally, and visual acuity was significantly reduced. Both the A-waves and B-waves of the mfERG were depressed in the corresponding areas. At 4 weeks, neither visual acuity nor mfERG showed improvement, although the cotton-wool spots had resolved. Interestingly, at 6 months, visual acuity had improved significantly in the left eye, consistent with increased ratios of mfERG responses for the central area. CONCLUSION: There was no selective reduction of b-waves of the mfERG as anticipated in isolated inner retinal pathology. In this case, both the A-waves and B-waves were reduced, suggesting damage to both outer and inner retinal layers. 相似文献
42.
Katz DL Chan W Gonzalez M Larson D Nawaz H Abdulrahman M Yeh MC 《Preventive medicine》2002,34(6):608-615
BACKGROUND: Optimal behavioral interventions for sustainable weight loss are uncertain. We therefore conducted a study among overweight/obese women comparing conventional dietary counseling of individuals (counseling-based intervention) to a novel, group-based skill-building intervention. METHODS: Eighty subjects were randomly assigned to either the counseling-based or to the skill-building intervention. Outcomes included weight loss, dietitian hours per group and per unit weight loss, and dollars spent per group and per unit weight lost. RESULTS: Weight loss at 6 months (follow-up rate 61.3%) in the counseling-based group was 8.8 lb (P = 0.0001), and in the skill-building group was 3.8 lb (P = 0.01). A total of 160 dietitian hours were required for the counseling-based group, and 131 for the skilled-building group. The counseling-based group cost an average of $21 per pound lost, while the skill-building cost an average of $48 per pound lost (P = 0.16). CONCLUSIONS: At 6 months, individualized office-based counseling produced more weight loss than a skill-building approach and cost less than half as much per pound of weight loss. Longer-term follow-up is required to determine if, as hypothesized, the skill-building intervention produces more sustainable weight loss. 相似文献
43.
Haq MR Kalatzis V Gubler MC Town MM Antignac C Van't Hoff WG Woolf AS 《Journal of the American Society of Nephrology : JASN》2002,13(8):2046-2051
Cystinosis is an autosomal recessive disorder associated with excessive lysosomal cystine accumulation secondary to defective lysosomal cystine efflux. CTNS, the gene mutated in cystinosis, codes for the lysosomal membrane protein cystinosin. Antisera were raised in rabbits to a carboxy-terminal oligopeptide sequence from cystinosin. Antisera were screened by Western blotting and immunocytochemical analyses of transfected COS-7 cells expressing either human wild-type cystinosin, a wild-type cystinosin-green fluorescent protein (GFP) fusion protein, or a fusion protein of GFP and mutant human cystinosin with a carboxy-terminal deletion. In Western blots, bands corresponding to cystinosin or cystinosin-GFP were observed in transfected cells but no signal was detected in cells expressing the carboxy-terminal mutant; preimmune sera yielded negative results in all three cases. In transfected cells expressing wild-type cystinosin, immunoreactivity appeared in subcellular vesicles. In cells expressing the wild-type cystinosin-GFP fusion protein, immunoreactivity colocalized with GFP fluorescence. Previous studies demonstrated that GFP fluorescence from this construct colocalized with immunostaining for a known lysosomal membrane protein, i.e., lysosome-associated membrane protein 2. In immunohistochemical analyses, cystinosin localized to tubule epithelia in three normal human kidneys, with a pattern similar to that of lysosome-associated membrane protein 2; cystinosin immunoreactivity was absent in kidneys from patients with a CTNS deletion. For the first time, antisera have been raised that localize cystinosin in cells in vitro and in vivo. 相似文献
44.
Mohammad Ali Pierre Goovaerts Nushrat Nazia M Zahirul Haq Mohammad Yunus Michael Emch 《International journal of health geographics》2006,5(1):45-11
Background
Disease maps can serve to display incidence rates geographically, to inform on public health provision about the success or failure of interventions, and to make hypothesis or to provide evidences concerning disease etiology. Poisson kriging was recently introduced to filter the noise attached to rates recorded over sparsely populated administrative units. Its benefit over simple population-weighted averages and empirical Bayesian smoothers was demonstrated by simulation studies using county-level cancer mortality rates. This paper presents the first application of Poisson kriging to the spatial interpolation of local disease rates, resulting in continuous maps of disease rate estimates and the associated prediction variance. The methodology is illustrated using cholera and dysentery data collected in a cholera endemic area (Matlab) of Bangladesh. 相似文献45.
Skull base involvement by a nasopharyngeal carcinoma shown by Tc-99m MDP SPECT but not by computed tomography 总被引:1,自引:0,他引:1
PURPOSE: Plain radiographs, computed tomography (CT), and more recently magnetic resonance imaging (MRI) are used routinely to stage carcinoma of the nasopharynx. Tc-99m methylene diphosphonate (MDP) SPECT is seldom used for local staging of the disease. MATERIALS AND METHODS: Plain radiographs and CT were used to stage squamous carcinoma of the nasopharynx in a 50-year-old man with a left XII nerve palsy. RESULTS: Findings of the plain radiographs were normal, whereas the CT scan revealed a nonhomogenous hyperdense mass in the nasopharynx but intact underlying bone. Given the symptoms, a Tc-99m MDP planar scan was ordered and showed no enhanced uptake, but SPECT images obtained at the same time revealed markedly increased focal radiotracer uptake in the region of the tumor, indicating osseous involvement. CONCLUSION: Possible bony invasion with a nasopharyngeal carcinoma may be better shown with MDP SPECT than with planar isotope bone scans, plain radiographs, or CT. 相似文献
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Mann M Haq W Zabel T Guenther E Zrenner E Ladewig T 《The European journal of neuroscience》2005,22(11):2735-2743
The purpose of this study was to investigate the role of intracellular calcium buffering in retinal ganglion cells. We performed a quantitative analysis of calcium homeostasis in ganglion cells of early postnatal and adult mice by simultaneous patch-clamp recordings in sliced tissue and microfluorometric calcium measurements with Fura-2. Endogenous calcium homeostasis was quantified by using the 'added buffer' approach which uses amplitudes and decay time constants of calcium transients to give a standard for intracellular calcium buffering. The recovery phase of depolarization-induced calcium transients was well approximated by a mono-exponential function with a decay time constant that showed a linear dependence on dye concentration. Endogenous calcium binding ratios were found to be 575 (n = 18 cells) in early postnatal and 121 (n = 18 cells) in adult retinal ganglion cells. With respect to ganglion cell degeneration at early postnatal stages, our measurements suggest that neuroprotection of a majority of developing ganglion cells partially results from a specialized calcium homeostasis based on high buffering capacities. Furthermore, the dramatic decrease of the intracellular calcium buffering capacity during ganglion cell development may enhance their vulnerability to neurodegeneration. 相似文献