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A case of cerebellopontine angle meningioma with restoration of hearing from a profoundly deaf state is presented. Meningiomas of the posterior fossa commonly present with decreased or absent hearing and can appear deceptively similar to acoustic neurinomas on radiographic and audiometric testing. Because total restoration of hearing can occur with meningioma, even with significant preoperative deficit, utilization of the translabyrinthine approach is less desirable if any preoperative question as to the diagnosis exists. Any hearing-impaired patient with a cerebellopontine angle mass that is not conclusively thought to represent acoustic neurinoma should be approached by the suboccipital technique to maximize the opportunity for restoration of hearing.  相似文献   
13.
Disposition of sandostatin, a new synthetic somatostatin analogue, in rats   总被引:1,自引:0,他引:1  
The distribution, excretion, and metabolism of Sandostatin, a long-acting octapeptide analogue of somatostatin, have been studied in the rat after iv administration. Similar plasma levels and excretion values were observed by using radioimmunoassay and HPLC-liquid scintillation techniques. For the latter technique Sandostatin was radiolabeled with either 14C or 3H. The plasma pharmacokinetics of Sandostatin were as follows: Vdss = 0.4 liter/kg, C/t = 4.2 ml/min, and t1/2 2.0 hr; this half-life was by far longer than that of somatostatin. The in vitro protein binding amounted to 59% in rat plasma; no Sandostatin was taken up by blood cells. The tissue concentrations of Sandostatin were similar when determined either by radioimmunoassay or by quantitative whole-body autoradiography; this suggests that the distribution of 3H or 14C radioactivity observed 0.5 hr after iv administration mostly represented unchanged Sandostatin. Kidney and liver were the only tissues in which Sandostatin levels were higher than in blood; high radioactivity levels were observed in the blood vessel walls, whereas levels in brain were insignificant. Unchanged drug accounted for most of the radioactivity found in plasma, urine, and bile, whereas only traces of unchanged drug were detected in feces. These results demonstrated the metabolic stability of Sandostatin in the tissues, primarily in the liver, and suggested an extensive degradation in the intestinal tract. The degradation products consisted of smaller peptides and free amino acids. About 50% and 20% of the applied dose were excreted as unchanged Sandostatin in bile and urine, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
14.
Transcranial Doppler ultrasound (TCD) recording is a non-invasive diagnostic procedure for the evaluation of the cerebral collateral flow in patients, in whom therapeutic ligation or resection of the common and/or internal carotid artery is planned. Patients are first examined under resting conditions, and then under manual compression of the ipsilateral carotid artery. Since January 1989, 31 ENT and neurosurgical patients have been examined. In all patients an immediate decrease in flow velocity in the middle cerebral artery (mca) of about 25% to 90% was recorded. In 42.8% of the patients the mca flow velocity reached 90% or more of its value under normal conditions within a short period. In 29% of the patients the mca flow velocity under manual compression of the carotid artery remained under 50% of its original value. In 68% of the cases TCD with manual compression of the carotid artery showed reliable results for the function of cerebral collateralisation as a prognostic factor of the risk of ischaemia due to haemodynamic changes after carotid ligation. In these cases no further examination of the cerebral collateral flow conditions was needed. The method is inexpensive, reproducible, and in comparison with cerebral angiography, convenient and non-hazardous for the patient.  相似文献   
15.
Objective: To demonstrate that emergency aortic valve replacement can be successfully performed in patients with critical aortic stenosis and reduced left ventricular function even in cardiogenic shock with associated severe multiple organ failure. Design: Retrospective, consecutive case series. Setting: Multidisciplinary intensive care unit of a tertiary care university hospital. Patients: Five patients admitted to the intensive care unit with critical aortic stenosis (aortic valve area 0.56 ± 0.13 cm2) and greatly reduced left ventricular ejection fraction (20 ± 3 %) in prolonged cardiogenic shock and associated multiple organ failure (Multiple organ failure score 6.8 ± 0.5; Acute Physiology, Age, and Chronic Health Evaluation III score 91 ± 27). Intervention: Emergency aortic valve replacement. Results: All patients survived with full recovery of organ function. At follow-up (18 ± 10 months) all patients were in New York Heart Association functional class I or II with improvement of left ventricular ejection fraction to 48 ± 25 %. Conclusions: This excellent outcome suggests that emergency aortic valve replacement should be strongly considered in patients with critical aortic stenosis even in cardiogenic shock and multiple organ failure.  相似文献   
16.
Eighty-four cases of extraosseous Ewing's sarcoma (EOE) were found during the pathology review of the Intergroup Rhabdomyosarcoma Study I and II. Patients commonly presented during or after adolescence with the most common primary sites including the trunk, extremities, and retroperitoneum. Males were slightly more affected. Histologic sections of 74 tumors in the pathology repository were re-reviewed with attention to rosette formation (positive in 18 cases) and glycogen deposition (++ in 21, + in 36, +/- in 11, and - in 2 of 70 cases examined). Fourteen tumors (7 with rosettes and 7 without) were selected for immunohistochemical and ultrastructural studies, and 13 showed single or multiple neural markers (neuron-specific enolase in 8, S-100 protein in 6, and neurosecretory-type granules in 9). These possible cases of neural EOE could be divided into three subgroups: tumor with bidirectional neuroblastic and schwannian differentiation (5 cases), tumor with monodirectional neuroblastic differentiation (7 cases), and tumor with monodirectional schwannian differentiation (1 case). EOE with a neural nature may be categorized into a spectrum of peripheral primitive neuroectodermal tumors. Clinical, histopathologic, and biologic differences between this disease and conventional sympathetic neuroblastoma are discussed.  相似文献   
17.
Zusammenfassung Von 4000 unausgewählten poliklinischen Patienten hatten 395 (10%) eine Hyperlipoproteinämie. 22 Patienten (5,6% der Fälle mit Vermehrungen der Serumlipide, 0,55% der Gesamtpatienten) zeigten elektrophoretisch das Bild einer breiten -Bande. In 2 Fällen (ca. 10% der Patienten, deren Seren in der Agarose-Elektrophorese keine scharfe Trennung der - und Prä--Lipoproteine ergab, 0,25% der Hyperlipoproteinämien) konnte eine Hyperlipoproteinämie Typ III gesichert werden. Bei Beschränkung der Ultrazentrifugation auf Seren mit breiter -Bande werden nicht alle Hyperlipoproteinämien des Typs III erfaßt. Andererseits ist der Anteil des Typs III bei Lipoproteinämiemustern mit unscharfer Trennung von - und Prä--Lipoproteinen (breite -Bande) verhältnismäßig gering.Herrn Prof. Dr. H. H. Bennhold zum 80. Geburtstag gewidmet.  相似文献   
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The proliferative T cell responses to poly(GluLysTyr) (GLT) and poly(GLULysPhe) (GLPhe) are restricted by the E alpha E beta class II MHC molecule (E) in most responded strains. Some nonresponder strains that carry responder E beta, but cannot express cell surface E molecules, can complement with other nonresponder strains that provide the missing E alpha chain needed for the expression of E molecules and for responsiveness to GLT and GLPhe. Here another type of complementation is described between two E-nonexpressor haplotypes, H-2f and H-2s, which result in E-nonexpressor F1 hybrids, which are responders to GLT. The restriction element involved in this response is an Af/As hybrid molecule. The data support the hypothesis that conformational determinants resulting from the free association of alpha and beta chains in heterozygotes can increase the immune potential of the individual.  相似文献   
20.
Preparing monolayers of non-adherent mammalian cells   总被引:5,自引:0,他引:5  
A simple method is described for preparing monolayers of non-adherent cells, using concanavalin A to bind the cells to wells of plastic microtest plates. The method was used successfully with all 202 human cell types tested, which included 23 tissue culture lines, 165 fresh specimens of all major histological types of leukemia and lymphoma, 20 fresh myelomas, 2 fresh thymomas, normal spleen and lymph node cells, fractionated T lymphocytes and B lymphocytes from peripheral blood, and cultured fetal amniotic cells. All cell types attached firmly, and were not detached by subsequent vigorous washing. In contrast, attempted attachment of cells in serum free medium, or with poly-L-lysine or glutaraldehyde, was ineffective with many cell types. We used the monolayers as target cells for antibodies to cell surface antigens, utilizing immune rosetting or complement-mediated cytotoxicity. This procedure should simplify most assays involving non-adherent target cells.  相似文献   
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