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Biologic distribution data in the rat were obtained for the alpha-1 adrenoceptor imaging agent (+/-) 2-[beta-(iodo-4-hydroxyphenyl)ethylaminomethyl]tetralone (HEAT) labeled with [125I]. The major excretory routes were through the liver (67%) and the kidney (33%). Internal radiation absorbed dose estimates to nine source organs, total body, the GI tract, gonads, and red bone marrow were calculated for the human using the physical decay data for [123I]. The critical organ was found to be the lower large intestine, receiving 1.1 rad per mCi of [123I]HEAT administered. The total-body dose was found to be 58 mrad per mCi.  相似文献   
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Melorheostosis is a rare sclerosing bone dysplasia that is characterized by a localized, diffuse thickening of the cortical bone. This condition usually affects the appendicular skeleton and associated soft tissue and rarely affects the craniofacial complex. The etiology of this condition is obscure. Diagnosis of melorheostosis relies on clinical, radiographic, and histological correlation. Only 8 cases of melorheostosis involving the craniofacial complex have been reported. We report 2 new cases of isolated melorheostosis involving the maxilla and mandible, together with differential diagnostic considerations. To our knowledge, involvement of the maxilla only has not been previously reported.  相似文献   
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The establishment and characterization of 11 human lung cancer cell lines are described in this article. Nine of these cell lines were established over a 5-year period, from 1983 to 1988, from patients treated at the Kingston Regional Cancer Centre. These include eight definite or probable small cell lung cancer (SCLC) lines and one adenocarcinoma line. In addition, two other SCLC cell lines were characterized. All of the lines have been in continuous culture for more than 2 years. The clinical histories of the patients from whom the cell lines were derived are outlined here. Several features of the cell lines are presented, including the following: (1) a comparison of the histologic features of the cell lines with the original biopsy specimens; (2) the expression of various markers, including cytokeratin, carcinoembryonic antigen, calcitonin, and neuron-specific enolase; (3) activities of the enzymes l-dopa decarboxylase and the brain isoenzyme of creatine kinase; (4) growth characteristics; (5) cloning efficiency in soft agar; (6) tumorigenicity in nude mice; and (7) cytogenetic studies. These cell lines, obtained directly from patients with a spectrum of drug-sensitive and drug-resistant tumors, will be valuable in vitro models of sensitivity and resistance to chemotherapy in lung cancer.  相似文献   
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Back pain among nurses is a common problem. Prior studies of this problem have been based on cross-sectional or retrospective data. This 18-month prospective study involving nurses newly graduated from nursing school investigated personal, worksite, and training factors associated with future risk of back pain. Each nurse underwent a preliminary interview and periodic follow-ups to identify those with back injuries. Contingency tables and logistic regression analyses demonstrated that prior significant back pain episodes (evidenced by previous job changes because of back pain, frequent medication use, etc.) were associated with increased future risk. Training at nursing school or on the job did not have a protective effect. This pilot study therefore suggests factors useful in placement and counseling of new nurses and indicates the need for further implementation of mechanical lift assist device use. © 1994 Wiley-Liss, Inc.  相似文献   
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We present three patients with Treacher Collins or Pierre Robin syndromes who had historical and physical evidence of airway obstruction, difficulty feeding, and sleep disturbances. These preoperative findings correlated with difficult airway management intraoperatively. Based on this experience, we recommend that children with obstructive symptoms have laryngoscopy prior to anaesthetic induction. If the glottic opening is visualized, inhalational induction can proceed. If the glottic structures cannot be visualized, then the anaesthetist must choose between awake oral or nasal intubation, elective tracheostomy, or fiberoptic intubation. In all cases, a tracheostomy tray should be ready and a surgeon experienced in paediatric tracheostomy should be in attendance. After intubation, anaesthesia is best maintained with oxygen and a potent inhalational agent. Extubation should only be done with the patient fully awake and with emergency airway equipment immediately available. Postoperatively, these patients should be transferred to an intermediate care area or intensive care unit where they can be observed closely since delayed complications of airway obstruction are common in this group of patients.  相似文献   
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To assess the long-term efficacy of patellar resurfacing, 100 knees were evaluated in 84 patients. The operations were performed between 1978 and 1982. The follow-up period ranged from 60 to 103 months. The diagnosis was degenerative joint disease (DJD) in 83%, rheumatoid arthritis in 12%, and miscellaneous in 5% of the knees. The implant (47 knees) and nonimplant (53 knees) groups were comparable with respect to age, body size, and length of follow-up period. The analysis revealed equivocal results. Considering all diagnostic categories combined, rest pain was marginally better in the resurfaced group (p = 0.04), but this difference resulted from an unequal distribution of subjects between mild and zero pain categories. Pain with walking, maximum walking distance, ability to climb stairs and rise from a chair, active arc of motion, extensor lag, and quadriceps strength were similar in the two groups. When the DJD group was considered separately, no significant difference emerged. There was little evidence to support a recommendation for routine patellar resurfacing in total knee arthroplasty.  相似文献   
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