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111.
We report a case of a middle-aged woman in whom a transesophageal echocardiogram showed a mass-like lesion posteriorly near the descending thoracic aorta. We were able to make a definitive diagnosis of this mass as a hiatal hernia because of a thick inner lining measuring 6-9 mm in thickness similar to the stomach mucosa, and the presence of a few microbubbles within the mass. In addition, the microbubbles increased considerably after 10 cc of agitated normal saline flush via a nasogastric tube.  相似文献   
112.
In the present study, we describe the usefulness of the recently developed technique of live three-dimensional transthoracic echocardiography in the assessment of normal cardiac structures and adjacent vessels using the right parasternal and supraclavicular approaches. Examples of some abnormalities diagnosed from these approaches are also illustrated.  相似文献   
113.
Adenomas of the non-pigmented epithelium of the ciliary body are rare neoplasms and most of the studies are in the form of case reports. There are only 27 documented cases of acquired neoplasm of the non-pigmented ciliary epithelium (NPCE) reported in the English literature. In most reports, there was a clinical suspicion of melanoma and the diagnosis of NPCE adenoma was made on histopathological evaluation of the resected tissue. The entity has not been reported in the Pakistani population to date. This report describes a case of ciliary body adenoma of NPCE in a 27 year old Pakistani man. The histological and immunohistochemical profiles were typical of the adenomas described in the literature.  相似文献   
114.
115.
Malignant hyperthermia refers to covert myopathies, which do not affect the individual during daily life activities, but may lead to life-threatening tachycardia, rigor, labile blood pressure and most importantly high-grade temperature when exposed to general anaesthesia. This conditions is mimicked by thyroid storm, neuroleptic malignant syndrome, phaeochromocytoma and sepsis. We present a presumptive case of malignant hyperthermia.  相似文献   
116.
Enzyme immobilization in novel alginate-chitosan core-shell microcapsules   总被引:13,自引:0,他引:13  
Taqieddin E  Amiji M 《Biomaterials》2004,25(10):1937-1945
Alginate-chitosan core-shell microcapsules were prepared in order to develop a biocompatible matrix for enzyme immobilization, where the protein is retained either in a liquid or solid core and the shell allows permeability control over substrates and products. The permeability coefficients of different molecular weight compounds (vitamin B2, vitamin B12, and myoglobin) were determined through sodium tripolyphosphate (Na-TPP)-crosslinked chitosan membrane. The microcapsule core was formed by crosslinking sodium alginate with either calcium or barium ions. The crosslinked alginate core was uniformly coated with a chitosan layer and crosslinked with Na-TPP. In the case of calcium alginate, the phosphate ions of Na-TPP were able to extract the calcium ions from alginate and liquefy the core. A model enzyme, beta-galactosidase, was immobilized in the alginate core and the catalytic activity was measured with o-nitrophenyl-beta-D-galactopyranoside (ONPG). Change in the activity of free and immobilized enzyme was determined at three different temperatures. Na-TPP crosslinked chitosan membranes were found to be permeable to solutes of up to 17,000Da molecular weight. The enzyme loading efficiency was higher in the barium alginate core (100%) as compared to the calcium alginate core (60%). The rate of ONPG conversion to o-nitrophenol was faster in the case of calcium alginate-chitosan microcapsules as compared to barium alginate-chitosan microcapsules. Barium alginate-chitosan microcapsules, however, did improve the stability of the enzyme at 37 degrees C relative to calcium alginate-chitosan microcapsules or free enzyme. This study illustrates a new method of enzyme immobilization for biotechnology applications using liquid or solid core and shell microcapsule technology.  相似文献   
117.
Ossifying fibromyxoid tumor (OFT) of soft parts is a benign soft tissue tumor commonly located in the extremities. In this paper, a 3-week-old boy presented with left nasal mass at birth. He was found to have an OFT involving the ethmoid sinus. To the best of our knowledge, this is the first reported case of OFT in a newborn with involvement of the sinuses. This rare tumor should alert Pediatric Otolaryngologists to include it in the differential diagnosis of pediatric soft tissue tumors in sinuses.  相似文献   
118.
BACKGROUND AND PURPOSE: This study was undertaken to clarify whether idiopathic edema is a marker for obstructive sleep apnea (OSA), independent of level of obesity, in patients with normal left ventricular function. PATIENTS AND METHODS: Seventy-eight ambulatory, obese, adults, 44 with bilateral, pitting pre-tibial edema, and 34 without edema, from an inner city family practice and a suburban family practice enrolled from July 1995 until March 2003. Edematous subjects, but not non-edematous subjects, underwent echocardiography, urinalysis, and blood test evaluations to ensure that cardiac, renal, hepatic, and thyroid functions were normal. All subjects underwent spirometry, pulse oximetry on room air, and polysomnography evaluations. RESULTS: Compared to the non-edematous subjects, the edematous subjects were more obese (body mass index=47.0+/-9.3 versus 36.5+/-4.6 kg/m2, P=0.002), had more severe OSA (apnea-hypopnea index (AHI)=34.1+/-27.7 versus 17.0+/-19.4, P=0.002), and had lower oxygen saturations (96.2+/-2.0 versus 97.1+/-1.5%, P=0.05). Using an AHI > or = 15 as the criteria for diagnosing OSA, there was an association between edema and OSA in women (P=0.02) but not men. CONCLUSIONS: In subjects with normal left ventricular function, idiopathic edema is associated with OSA in women.  相似文献   
119.
Defining the pathogenicity of optineurin in juvenile open-angle glaucoma   总被引:6,自引:0,他引:6  
PURPOSE: Juvenile open-angle glaucoma (JOAG) differs from primary open-angle glaucoma in that it is usually a more severe phenotype and has an earlier age of onset. Optineurin was recently associated with a variant of POAG that is characterized by intraocular pressure within normal limits: normal-tension glaucoma. The present study tested whether OPTN sequence changes play a role in early-onset glaucoma characterized by elevated intraocular pressure. METHODS: Sixty-six patients with JOAG characterized by high intraocular pressure were screened for mutations. Mutational analysis was performed with a combination of restriction enzyme digestion, single-strand conformation polymorphism, and direct sequencing. The effects of select changes on exon splicing were assessed using bioinformatic modeling approaches and RT-PCR. RESULTS: Ten sequence changes were identified, of which H486R was strongly suggestive of pathogenicity. H486R represents the first reported OPTN mutation associated with JOAG. Also, L41L is proposed to confer an increased susceptibility to the development of JOAG. Most of the other sequence changes observed were not thought to be biologically significant. The frequency of the previously reported M98K allele was not increased in the JOAG population studied but showed the previously reported skewed distribution in the POAG study population. The changes identified were not shown to affect the splicing machinery. CONCLUSIONS: The results of this work support the hypothesis that mutations in OPTN are not specifically associated with low-pressure glaucoma, but can play a role in JOAG.  相似文献   
120.
BACKGROUND: Sustained effects following withdrawal of n-3 PUFAs are unknown. METHODS: Clinical outcome [cardiac death, resuscitation, recurrent myocardial infarction (MI) or unstable angina pectoris] was assessed after prolonged wash-out following randomised treatment with high-dosed n-3 PUFAs or corn oil for 12-24 months in 300 acute MI patients. Atherothrombogenic risk markers, serum glucose and markers of lipid peroxidation and inflammation were evaluated in 89 out of the 100 last included patients. RESULTS: After a total median observation period of 45 (range 0-53) months no intergroup difference in prognosis was observed for any of the cardiac events. Favourable effects on serum triglycerides and HDL-cholesterol by n-3 PUFAs were lost after washout, but triglycerides decreased in the corn oil as compared to the n-3 group, P < 0.001. The decline in total cholesterol after withdrawal was similar in both groups. No intergroup difference in the change in thiobarbituric acid-malondialdehyde, a marker of lipid peroxidation, ultrasensitive C-reactive protein, homocysteine, glucose or blood platelets was noted at sustained follow-up. CONCLUSION: Clinical outcome was similar in both patient groups, and the atherothrombogenic risk improvement by n-3 PUFAs was lost after prolonged wash-out. Withdrawal did not affect homocysteine, glucose or markers of lipid peroxidation or inflammation.  相似文献   
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