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71.
72.
Wilson disease is an autosomal recessive disorder of copper transport, caused by the reduced or absent function of the Wilson disease gene ATP7B on chromosome 13. The disease is characterized by reduced incorporation of copper into the ceruloplasmin protein and reduced excretion of copper into the bile. Wilson disease is effectively treated if detected early. Our study goals were to determine the feasibility of a population screening for Wilson disease using dried blood spots and to characterize the base-line ceruloplasmin concentration in newborn blood spots of patients with Wilson disease. Ceruloplasmin was analyzed in dried blood spots obtained from 353 Mayo Clinic pediatric volunteers aged from 3 months to 18 years and from 1045 anonymous newborn screening specimens using a sandwich enzyme-linked immunosorbent assay. The original newborn screening blood spots were retrieved from two patients with Wilson disease along with age-matched controls for ceruloplasmin determination. The mean (+/-SD) concentration of ceruloplasmin in the pediatric blood spots was 40.0+/-14.4 mg/dL (range 13.1 to >60 mg/dL) and newborn blood spots was 47.2+/-15.5mg/dL (range 6.5 to >60 mg/dL). Ceruloplasmin in the newborn blood spots from two Wilson disease patients were 2.6 and 2.8 mg/dL, respectively. The newborns affected with Wilson disease had significantly lower ceruloplasmin levels in blood spots than unaffected newborns. These findings support that presymptomatic screening for Wilson disease using dried blood spots could be possible, even in the newborn period.  相似文献   
73.
To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process.  相似文献   
74.
Purpose: To describe the clinical features, retinal architecture and tomographic configuration of a pigmented epiretinal membrane on optical coherence tomography (OCT). Methods: A 52‐year‐old man presented during a routine examination with an asymptomatic, darkly pigmented, pre‐retinal epiretinal membrane in his right eye. His best corrected visual acuity (BCVA) on Snellen charts was 20/25 in the right eye and 20/20 in the left. The patient complained of no visual symptoms or metamorphopsia. Results: In the fundus periphery there was a small, old, well pigmented retinal hole with pigmentation in its immediate vicinity, without signs of vitreal traction, which required no treatment. The foveal indentation was not apparent on OCT and a well demarcated hyperreflective band defined the pigmented epiretinal membranes (ERMs). Sequential fundus examination over a 2‐year period demonstrated no functional or anatomical deterioration attributable to the disease. Conclusions: Pigmented ERM may have different cellular origins depending on the underlying pathology. Patients with pigmented ERM and full VA should be followed by sequential OCT.  相似文献   
75.
OBJECTIVES: To introduce a creatinine biosensor and a total carbon dioxide content (TCO2) method for whole-blood measurements, to evaluate the clinical performance of a new transportable analyzer that simultaneously performs these two and six other tests (Na+, K+, Cl-, glucose, urea nitrogen, and hematocrit), and to assess the potential of the new analyzer for point-of-care testing in critical care by comparing results obtained by nonlaboratory personnel and by medical technologists. DESIGN: Multicenter sites compared whole-blood measurements with the transportable analyzer to plasma measurements from the same specimens with local reference instruments. One site compared whole-blood results produced by nonlaboratory personnel vs. medical technologists and evaluated day-to-day and within-day precision at the point of care. SETTINGS AND PATIENTS: Four medical centers in the United States. Venous and arterial specimens from 710 critically ill patients with a variety of diagnoses. Point-of-care testing in the emergency room and operating room. RESULTS: The linear regression analyses at the four medical centers showed the following: creatinine (a) slope, 0.91 to 1.22, (b) y intercept, -0.07 to 0.15 mg/dL, and (c) r2, 0.77 to 1.00; and TCO2: (a) slope, 0.64 to 1.00, (b) y intercept, 1.36 to 9.6 mmol/L, and (c) r2, 0.52 to 0.72 (yi, whole-blood analyses; xi, plasma reference measurements). Bland-Altman plots also were used to assess multicenter creatinine and TCO2 results. Of the other analytes, K+, glucose, and urea nitrogen had the highest r2-values. For the eight chemistry profile tests performed at the point of care (yi, nonlaboratory personnel results; xi, medical technologist results), the average value of r2 was 0.96 (SD 0.08) in the operating room and 0.96 (SD 0.06) in the emergency room, and mean paired differences (yi - xi) were not statistically or clinically significant. Precision was acceptable. CONCLUSIONS: The performance of the creatinine biosensor and the TCO2 method was acceptable for whole-blood samples. Comparisons of whole-blood results from the transportable analyzer and plasma results from the local reference instruments revealed analyte biases that may be attributed to differences between direct whole-blood analyses and indirect-diluted plasma measurements and other factors. Performance of nonlaboratory personnel and medical technologists was equivalent for point-of-care testing in critical care settings. The whole-blood analyzer should be useful when patient care demands immediate results.  相似文献   
76.
A 16-year old girl with insulin-dependent diabetes mellitus (8 years' duration) developed tropic malaria 7 weeks after her return from Kenya despite a longtime prophylaxis using pyrimethamine and sulfadoxine (Fansidar). The disease was detected during an episode of ketoacidosis which proved exceptionally difficult to manage. Adequate chloroquine therapy resulted in temporary recovery. A recurrence of malaria four weeks later was successfully treated with quinine and doxycycline. Intraleucocytary parasites were found during both these episodes. Already prior to antimalarial drug therapy the girls' preexisting retinopathy was found to have deteriorated.  相似文献   
77.
Background. The purpose of this study was to evaluate anatomical and functional results of vitreoretinal silicone oil surgery for complicated retinal detachments due to trauma and myopia in children and juveniles. Methods. We retrospectively reviewed the records of children and juveniles up to 17 years of age who had undergone vitreoretinal surgery with silicone oil instillation for the above causes between 1990 and 1997. A total of 30 eyes of 29 patients were operated on, 24 because of trauma and the remaining 6 because of retinal detachment in high myopia. There was a mean postoperative follow-up period of 1.7 years. Silicone oil could be removed from 18 of the 30 eyes after a mean of 4.7 months. The median number of vitrectomies performed per eye was two (range one to five). Results. In 21 of 30 eyes (70%) the retina could be reattached after one or more surgeries. Silicone oil was removed from 16 of these 21 eyes (53%) which was defined as anatomical success. Visual acuity increased (14 eyes, 48.3%) or remained unchanged (9 eyes, 31%) in 23 of 29 eyes (79.3%). Visual acuity decreased in 6 of 29 eyes (20.7%) despite surgery. Two eyes (6.7%) had to be enucleated due to bulbar phthisis. Seventeen eyes reached a postoperative visual acuity of at least counting fingers. In one child functional tests could not be performed due to young age. Conclusion. Vitreoretinal surgery with silicone oil endotamponade has become a standard procedure in treating complicated retinal pathologies in children and juveniles. In very young patients it is thought that silicone oil instillation has advantages over gas endotamponade since it is very difficult for children to keep the proper face-down positioning after the procedure. The retinal reattachment rate is encouraging. In the majority of cases visual acuity greater than or equal to counting fingers and thus orienting vision was reached postoperatively. In few cases even reading vision was regained.  相似文献   
78.
PURPOSE: To prove the role of the vitreous in retinal detachment surgery with scleral buckling procedures, we retrospectively investigated the charts of patients who were operated on for retinal detachment by scleral buckling between January 1995 and June 1997. METHODS: Out of a total of 718 cases, 41 retinal detachments occurred in previously vitrectomized eyes. The buckling procedure consisted of silicone sponge explants in 513 cases (254 radial, 259 circumferential) and of encircling elements in 202 cases. Three eyes received a temporary balloon. The minimal follow-up was 3 months. RESULTS: After primary surgery in the 677 nonvitrectomized eyes, the retina was attached in 482 eyes (71.2%), after reoperation in 627 eyes (92.6%). With up to 3 reoperations (including vitrectomy with gas or silicone oil tamponade in 79 eyes), the final success rate was 98.7%. The corresponding reattachment rates in the 41 vitrectomized eyes were 82.9% after primary surgery and 97.6% after reoperation. Repeated surgery in 6 eyes consisted of successful internal tamponade by silicone oil. The reattachment rates after primary buckle procedure are of most interest to the role of the vitreous: the highest success rate (82.9%) was achieved in the vitrectomized eyes versus 71.2% in the nonvitrectomized eyes. The difference is statistically not significant. CONCLUSIONS: We therefore conclude that the absence of the vitreous has no adverse effect on the results of buckling procedures for retinal detachment. The choice of the surgical technique in treating retinal detachments in vitrectomized eyes should only determined by retinal findings such as the number and extent of breaks or the presence and stage of proliferative vitreoretinopathy.  相似文献   
79.
PURPOSE: To determine if at clinical dosages, the topical nonsteroidal anti-inflammatory drugs diclofenac and ketorolac decrease corneal sensitivity, and if there is a difference in discomfort on instillation. METHODS: In a double-masked study, 30 patients were randomized to receive two of three topical drops, Endosol, diclofenac sodium, and ketorolac tromethamine. A microaesthesiometer was used to evaluate corneal sensation. Baseline corneal sensitivity was obtained on each patient. Corneal sensory thresholds were remeasured at 7 and 15 minutes following eyedrop application. Patients also completed a questionnaire that graded the burning caused by the medications. RESULTS: No significant decrease in corneal sensory thresholds was found with diclofenac or ketorolac compared with control at baseline (P = .50), 7 minutes (P = .41), or 15 minutes (P = .82). There was significantly more burning with diclofenac and ketorolac compared to control. There was a small but not statistically significant (P = .28) trend of more burning with ketorolac than diclofenac. CONCLUSION: Neither diclofenac nor ketorolac were found to decrease corneal sensation compared to control. There was no significant difference in burning upon instillation reported by patients.  相似文献   
80.
A number of circulating breakdown products of collagen or other components of extracellular matrix, matrix degrading metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) have been proposed as markers of hepatic fibrosis. However, the published results lack consistency. Since many of the patients with fibrosis studied were alcoholics, the question was raised whether recent alcohol consumption may affect the results obtained. Using sandwich-type assays of radioimmunoassay technology with corresponding antibodies, we studied eight markers of liver fibrosis: laminin, tenascin, undulin, TIMP-1, collagen VI, procollagen type III (PIIINP), hyaluronic acid (HA) and MMP-2. A group of 10 alcoholics was studied after significant alcohol consumption and following 2 weeks of abstinence, verified with repeated breath alcohol measurement. Laminin was significantly reduced at 1 week (22%) and at 2 weeks (30%). Similarly, tenascin and undulin were also significantly decreased. By contrast, TIMP-1, collagen VI, PIIINP, HA and MMP-2 did not significantly change. The mode of action of alcohol on these tests is unknown. These differences must be considered when using those measurements to assess liver fibrosis.  相似文献   
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