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941.
942.
This article presents three cases of decreased vision due to acquired hyperopia, which were caused by a chalazion of the upper eyelid. Through manifest refraction and computerized corneal topographic analysis, acquired hyperopia associated with central corneal flattening was revealed. These findings were responsible for the blurred vision that was reversed by chalazion resolution or removal. Although not usually considered a risk factor for refractive disorders other than astigmatism, chalazia of the upper eyelid can present as a decrease in vision associated with reversible central corneal flattening and acquired hyperopia.  相似文献   
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BACKGROUND: Abdominal pain in childhood is common yet frustrating when unexplained. OBJECTIVE: To describe the clinical features and outcome of 8 children (6 girls and 2 boys; mean[+/- SD] age, 13 +/- 2 years) with unexplained abdominal pain who underwent exploratory laparoscopy. SETTING: All 8 patients were examined at an academic pediatric gastroenterology center and referred for exploratory laparoscopy because of unexplained abdominal pain. Laparoscopy was offered after family agreement to pursue behavioral management if the pain and disability did not improve. RESULTS: In all 8 children, laparoscopy detected an anomaly at a site corresponding to that of the abdominal pain. Findings were adhesions in 7 children (3 colonic, 2 ileocecal, 1 gastric, and 1 appendiceal) and ovarian torsion in 1 child. At a mean follow-up of 12.6 months, the abdominal pain had completely resolved in 6 children, notably improved in 1 child, and continued unchanged in 1 child. Disability completely resolved in 2 of 3 children. CONCLUSIONS: In children with unexplained abdominal pain that is acute in onset, well described, and suggestive of peritoneal involvement, exploratory laparoscopy (1) successfully ends the cycle of abdominal pain in most cases; and (2) commonly identifies abnormalities, usually adhesions. However, whether laparoscopy, the placebo effect, or both promote the healing process is unclear. Further study is needed to develop criteria for referral for laparoscopic evaluation of unexplained abdominal pain.  相似文献   
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Light is known to be an important modulator of circadian rhythms. We tested the hypothesis than an enduring increase in the daytime environmental illumination level improves rest-activity rhythm disturbances in demented patients. Actigraphy was performed before, during, and after 4 weeks of increased illumination in the living rooms of 22 patients with dementia clinically diagnosed as probable Alzheimer's disease, multi-infarct dementia, dementia associated with alcoholism, or normal pressure hydrocephalus. The results indicated that during increased illumination, the stability of the rest-activity rhythm increased in patients with intact vision, but not in visually impaired patients.  相似文献   
949.
We received the clinical and pathologic features of 22 cases of papillary carcinoma of the thyroid that invaded the trachea and were treated by thyroidectomy and airway resection with or without reconstructive surgery over an interval of 16 years. We studied the fine relationships between lamina propria and lymphatics in the region between the isthmus of the thyroid and the trachea. The manner of invasion of papillary carcinoma of the thyroid was by blunt dissection along blood vessels and collagen fibers oriented perpendicularly to the tracheal lumen between cartilaginous rings. Although lymph node metastases were found in 14 patients (64%), we observed lymphangitic tumor in the tracheal mucosa in only three patients (14%). We devised a staging system for papillary carcinoma of the thyroid based on the extent of invasion of the trachea. Of the 11 patients with stage I, II, or III disease, none of six (0%) followed for 5 years died of thyroid cancer in the 5-year observation period; one patient in this group died later of thyroid cancer. Of the 11 patients with stage IV disease, five of seven (71%) followed for 5 years died of thyroid cancer in the 5-year observation period; one additional patient in this group died later of thyroid cancer.  相似文献   
950.
A preparation of low molecular weight heparin (Fragmin) was administered to patients with multiorgan failure receiving continuous venovenous hemodialysis. Three patients received a high-dose regimen (35 IU/kg bolus followed by 13 IU/kg infusion), and 7 received a low-dose regimen (8 and 5 IU/kg, respectively) for 36 h. High-dose Fragmin was associated with minimal clotting in the extracorporeal circuit. Plasma fibrinopeptide A levels declined, and mean anti-Xa activity was in the range 0.47-0.79 IU/ml. The urea equilibration coefficient (UEC) (100% at initiation) remained above 90% throughout. All 3 patients had mild bleeding episodes, which led to discontinuation of Fragmin in 1. During all low-dose treatments, marked thrombus formation occurred in the extracorporeal circuit, and in 2, the circuit clotted within the study period. Fibrinopeptide A levels further increased in 4 patients, and mean anti-Xa activity was in the range 0.27-0.53 IU/ml. UEC declined appreciably in 3 treatments (including the 2 in which early circuit clotting occurred). One patient experienced a mild bleeding episode. The low-dose Fragmin regimen produced safer anticoagulation in patients at risk from bleeding and is suitable for prolonged renal support although the tendency to thrombosis may necessitate more frequent circuit changes.  相似文献   
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