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41.
Seven cases of lipomatous masses within the liver parenchyma were demonstrated with computed tomography (CT). Five of these cases were obtained from a retrospective review of 50 cases of renal angiomyolipoma in which the liver was adequately demonstrated. The other two cases were from the files of the Armed Forces Institute of Pathology and had no associated renal lesions. Three of the five cases were associated with tuberous sclerosis. In all seven cases, the fatty tumors appeared on CT scans as a well-defined, 0.8-13-cm mass, with attenuation coefficients of less than -30 HU. On ultrasound studies, the lesions were well circumscribed, highly echogenic, and similar to hemangiomas. While distinctly rare lesions, these lipomatous masses are not as unusual as the literature would indicate. One may anticipate such masses in patients with renal angiomyolipomas and in a relatively high percentage of those with tuberous sclerosis.  相似文献   
42.
本文研究了唐松草新碱在水溶液中的氧化降解动力学。考查了pH值、离子强度、温度和氧含量的影响,水溶液中的氧化降解速率常数由荧光法测定。结果表明,唐松草新碱在过量氧存在下,其氧化降解反应服从假一级反应动力学方程式,速率常数可由下式表示:其速率常数主要受介质的pH值和氧含量的影响,在pH 7.2条件下没有观测到原盐效应。  相似文献   
43.
Titelbaum  DS; Hayward  JC; Zimmerman  RA 《Radiology》1989,173(3):663-667
Studies of 23 pediatric patients with pachygyriclike changes (PLCs) examined with computed tomography (CT) and magnetic resonance (MR) imaging were reviewed to determine topographic patterns and correlate them with various clinical syndromes and degrees of neurologic impairment. Three types of topographic distributions were identified: unilateral, diffuse, and bilateral nondiffuse (of which eight of 10 showed frontotemporal predominance). PLCs were an isolated finding in seven patients, were associated with various congenital syndromes in nine patients, and were associated with congenital infection in seven patients, six of whom showed marked white matter abnormalities. Although most patients had severe developmental delay, three with nondiffuse PLCs had less severe impairment, permitting less required care.  相似文献   
44.
PURPOSE: To study the long-term clinical course of North American chronic angle-closure glaucoma (CACG) patients with optic disc damage and visual field loss in the presence of an angle closed at least partially by peripheral anterior synechiae and to compare it with a similar group of Singaporean patients. DESIGN: A retrospective, interventional case-control study series. PARTICIPANTS: Fifty-one patients (80 eyes) diagnosed with CACG with glaucomatous optic nerve head and visual field damage at a New York hospital from January 1990 through December 1994. All study eyes underwent laser peripheral iridotomy (LPI). METHODS: The presenting features, management, and subsequent long-term intraocular pressure (IOP) outcome were analyzed and compared with 65 Asian patients (83 eyes) from a Singapore hospital who were similarly diagnosed during the same period. MAIN OUTCOME MEASURES: The long-term outcome after LPI was assessed in terms of IOP and the requirement for additional therapy. RESULTS: The mean presenting IOP was higher in the Singapore eyes (40 +/- 15 mmHg) compared with the New York eyes (31 +/- 12.5 mmHg). All 80 New York eyes (100%) and 78 of 83 Singapore eyes (94%) required further treatment to control IOP during follow-up. Of the eyes with a subsequent rise in IOP, 33 of 80 eyes (41.3%) compared with 34 of 83 eyes (41.0%) of the Singapore patients were controlled with additional topical medication. Of the New York eyes, 25 of 80 (31.3%) eventually underwent filtering surgery, compared with 44 of 83 (53.0%) in the Singapore study. The other 22 eyes (27.5%) in the New York group went on to additional laser procedures, peripheral iridoplasty, laser trabeculoplasty, or a combination thereof, after which IOPs were controlled and no surgery was required. There was no similar comparison for the Singapore group, because these eyes went directly on to surgery. CONCLUSIONS: Despite the presence of a patent LPI, most eyes with CACG presenting with elevated IOP and having both optic disc and visual field damage in both populations required further treatment to control IOP. Results in the American population are similar to that reported in Asian patients.  相似文献   
45.
46.
OBJECTIVE: To examine the characteristics of infants suffering from failure to thrive in a community based cohort in Israel and to ascertain the effect of failure to thrive on their cognitive development. METHODS: By review of records maintained at maternal and child health clinics in Jerusalem and the two of Beit Shemesh, epidemiological data were obtained at age 15 months on a cohort of all babies born in 1991. For each case of failure to thrive, a matched control was selected from the same maternal and child health clinic. At age 20 months, cognitive development was measured, and at 25 months a home visit was carried out to assess maternal psychiatric status by questionnaire, and the HOME assessment was performed to assess the home environment. RESULTS: 3.9% of infants were found to have fallen below the third centile in weight for at least three months during the first year of life. Infants with failure to thrive did not differ from the general population in terms of obstetric or neonatal complications, birth order, or parents' ethnic origin, age, or years of education. The infants with failure to thrive did have lower birthweights and marginally smaller head circumferences at birth. Developmental assessment at 20 months of age showed a DQ of 99.7 v 107.2 in the matched controls, with 11.5% having a DQ below 80, as opposed to only 4.6% of the controls. No differences were found in maternal psychiatric problems as measured by a self report questionnaire. There were, however, significant differences in subscales of the HOME scale. CONCLUSIONS: (1) Infants who suffered from failure to thrive had some physiological predispositions that put them at risk; (2) failure to thrive may be an early marker of families providing suboptimal developmental stimulation.  相似文献   
47.
48.
Wound bed preparation: a systematic approach to wound management   总被引:6,自引:0,他引:6  
The healing process in acute wounds has been extensively studied and the knowledge derived from these studies has often been extrapolated to the care of chronic wounds, on the assumption that nonhealing chronic wounds were simply aberrations of the normal tissue repair process. However, this approach is less than satisfactory, as the chronic wound healing process differs in many important respects from that seen in acute wounds. In chronic wounds, the orderly sequence of events seen in acute wounds becomes disrupted or "stuck" at one or more of the different stages of wound healing. For the normal repair process to resume, the barrier to healing must be identified and removed through application of the correct techniques. It is important, therefore, to understand the molecular events that are involved in the wound healing process in order to select the most appropriate intervention. Wound bed preparation is the management of a wound in order to accelerate endogenous healing or to facilitate the effectiveness of other therapeutic measures. Experts in wound management consider that wound bed preparation is an important concept with significant potential as an educational tool in wound management.
This article was developed after a meeting of wound healing experts in June 2002 and is intended to provide an overview of the current status, role, and key elements of wound bed preparation. Readers will be able to examine the following issues;
• the current status of wound bed preparation;
• an analysis of the acute and chronic wound environments;
• how wound healing can take place in these environments;
• the role of wound bed preparation in the clinic;
• the clinical and cellular components of the wound bed preparation concept;
• a detailed analysis of the components of wound bed preparation.
(WOUND REP REG 2003;11:1–28)  相似文献   
49.
Capusten  BM; Azouz  EM; Rosman  MA 《Radiology》1984,152(3):693-694
Radiographs, computed tomograms, and radionuclide bone scans were obtained preoperatively in three children with fibromatosis involving the bones and soft tissues of the extremities. Two of the children had identical scar-like bone lesions of the proximal tibia, which, to the authors' knowledge, have not been reported before in this disease. The lesions recurred in two children.  相似文献   
50.
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