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31.
Ultrasonographic features of six leiomyosarcomas of the inferior vena cava are described. In most cases, the presentation is typical enough to strongly suggest the histologic diagnosis. The tumor is usually greater than 10 cm long, hypoechoic, heterogeneous. Cystic components can be found. It is sharply demarcated from neighboring organs which are displaced. The mass is located at the very place of the inferior vena cava, the lumen of which is no longer seen. It is fusiform shaped, surprisingly sparing the aorta. Differential diagnosis along with other radiologic examinations, pathologic findings, and prognosis are discussed.  相似文献   
32.
31P Nuclear magnetic resonance (NMR) spectroscopy and 1H NMR imaging were used to examine the effect of short-term ethanol feeding on the rat testis. Weanling rats were pair-fed for 10 weeks either on ethanol containing liquid diet (36% ethanol of total calories) or a diet in which dextrimaltose was isocalorically substituted for the ethanol of the alcohol-containing diet. In vivo 31P NMR of the testes was used to determine the intratesticular pH and the relative concentrations of various phosphorus-containing metabolites. The integrity of the blood-testes barrier was evaluated using 1H NMR imaging following a gadolinium diethylene tetramine pentaacetic acid derivative (Gd-DTPA) administration as a vascular contrast agent. After the completion of NMR studies, the testis and the liver were freeze-clamped to allow for the assay of their adenosine-5'-triphosphate (ATP) contents. Serum was assayed for its content of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alcohol and testosterone. Ethanol feeding resulted in the following: (a) a reduction in the body weight (p less than 0.05), (b) a reduction in the testicular phosphodiesters (PDE) PDE/ATP ratio (p less than 0.05), (c) an increased change in the testis image intensity difference between pre- and post-iv Gd-DTPA images, (c) a reduction in the testicular and hepatic content of ATP, and (d) increased serum levels of AST and ALT.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
33.
Objectives/Hypothesis: Vocal rehabilitation of patients who have undergone laryngectomy is best accomplished by a tracheoesophageal puncture. Optimal function of the prosthesis requires an adequate stoma. Patients with tracheostomal stenosis require revision of the stoma if vocal rehabilitation is to take place. Revision and tracheoesophageal placement are usually done as two separate procedures. Creating a tracheoesophageal fistula at the time of stomal revision has not been addressed in the literature. Study Design: Prospective analysis and follow-up of 10 patients undergoing simultaneous tracheoesophageal puncture and stomal revision for tracheostomal stenosis between 1991 and 1996. Methods: Ten patients were reviewed. An inferiorly based V-Y advancement flap was used so as not to interfere with the tracheoesophageal puncture. All patients had received radiation prior to revision and tracheoesophageal puncture. Patients were followed for a minimum of 2 years (range, 2–6 y; median, 3 y). Results: All patients maintained an adequate stoma without stenting. Eight of ten patients (80%) developed and maintained good tracheoesophageal speech. Two patients had their speech fistulas removed. There were no intraoperative or postoperative complications. Conclusions: Creation of a tracheoesophageal fistula at the time of stomal revision allows for vocal rehabilitation with a single visit to the operating room. Laryngoscope, 108:1509-1513, 1998  相似文献   
34.
The diagnosis of nontraumatic intracranial hemorrhage is currently made by computed tomography and is rarely problematic. The causes of bleeding are very numerous. It is important to determine the cause of the hemorrhage promptly, because there may be a recurrence of bleeding. Guidelines for radiologists are proposed and discussed here.  相似文献   
35.
BACKGROUND: The deliberate use of ketoconazole to reduce the need for cyclosporine (CsA) is not new, but it is particularly relevant because of the high cost of CsA. Many studies have documented this benefit in renal and cardiac transplants, but this co-administration has not been reported in patients with nephrotic syndrome. METHODS: This retrospective study included 207 nephrotic patients who were steroid resistant, dependent or frequent relapsers and received CsA therapy. Among these patients 153 received daily ketoconazole therapy in a dose of 50 mg with concomitant decrease of one-third of the CsA dose while 54 patients received CsA alone. The majority of our cases were children (179 were below 18 years) and male to female ratio was 1.7:1. RESULTS: The great majority of the study population received the drugs for 1-2 years. Patients who received CsA and ketoconazole were comparable with those who received CsA alone regarding age, sex, duration of renal disease, renal pathology, severity of nephrotic syndrome, renal function, hepatic function and steroid response. Co-administration of ketoconazole significantly reduced mean doses of CsA by 37% after 1 month and 47% at 1 year with overall net cost savings of 37%. Hepatic functions remained within the normal range in both groups. Additionally, co-administration of ketoconazole significantly improved the response to CsA therapy, successful steroid withdrawal and decreased the frequency of renal impairment. CONCLUSIONS: Co-administration of keto with CsA in idiopathic nephrotic patients significantly reduces CsA costs and may improve its response.  相似文献   
36.
Excitation functions of the reactions (nat)Sb((3)He,xn)(124,123,121)I were measured from their respective thresholds up to 35 MeV, with particular emphasis on data for the production of the medically important radionuclide (124)I. The conventional stacked-foil technique was used. From the experimental data the theoretical yields of the three investigated radionuclides were calculated. The yield of (124)I over the energy range E9(30He) = 35 --> 13 MeV amounts to 0.95 MBq/microA h. The radionuclidic impurities are discussed. A comparison of (3)He- and alpha-particle-induced reactions on antimony for production of (124)I is given. The alpha-particle-induced reaction on enriched (121)Sb and the (3)He-particle-induced reaction on enriched (123)Sb would lead to comparable (124)I yields, but the level of impurities in the latter case would be somewhat higher.  相似文献   
37.
Thirty-five plants are listed, which are used by traditional healers in the central and southern parts of Somalia. For each species are listed: the botanical name with synonyms, collection number, vernacular name, medicinal use, preparation of remedy and dosage. Results of a literature survey are also reported including medicinal use, substances isolated and pharmacological effects.  相似文献   
38.
Background. Primary adenocarcinoma of the larynx is a rare neoplasm. The incidence is reported as less than 1% of all laryngeal neoplasms in multiple series. Simultaneous primary adenocarcinoma and a solitary squamous cell carcinoma of the larynx is even rarer and only one case has been found on review of the literature. Methods. A case report of a 74-year-old man with a history of right-sided throat pain, odynophagia, and progressive hoarseness is presented with a review of the literature pertaining to this unusual case. Results. The patient was found to have three distinctly separate laryngeal lesions on direct laryngoscopy. Histopathologic diagnosis of adenocarcinoma was made on one of the three biopsied sites with the other sites being squamous cell carcinoma. Following Combined radiotherapy and surgical treatment, the patient has remained free of disease. Conclusions. Adenocarcinoma of the larynx is an infrequent and lethal disease. This case report and a review of the literature demonstrate that aggressive surgical management is indicated, although still may not result in improved survival. © 1994 John Wiley & Sons, Inc.  相似文献   
39.
Ultrasound examination in 8 patients with occlusive jaundice demonstrated non-lithiasic extrahepatic intracanalar obstacles, a malignant tumor in 4 and a non-tumoral process (granuloma on suture thread, ball sludge, hemobilia in 2 cases) in the other 4. Analysis of echographic data suggested possible differential diagnosis criteria for these two types of occlusion.  相似文献   
40.
Most pediatric cochlear implant programs support a team approach for post-implant services. However, individuals directly involved in the care of these children often have differing opinions on the child's performance. We describe our experience with four children, aged 3 to 10 at the time of implantation, who have used the Nucleus 22-channel cochlear implant device for at least nine months. A questionnaire, focusing on the individual's observations of the child's speech and hearing performance in their particular setting (i.e., clinic, home, school), was completed by the child's parent(s), therapist and classroom teacher. Overall, performance in structured settings (i.e., testing and therapy sessions) was not in agreement with performance in unstructured settings (i.e., classroom and home environments). The results suggest that different individuals interacting with the same child in different environments often have differing perceptions of the child's performance. Based on the information obtained on the four cases, we discuss factors to consider in assessing the real-life performance of pediatric cochlear implant recipients.  相似文献   
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