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71.
Acoustic rhinometry measures nasal cavity geometry by analysis of reflected acoustic impulses. Previously, the technique has been applied to normals, patients with septal deviations and rhinitis and to monitor the medical treatment of nasal polyps. To date, no study has been published to validate the application of this technique where nasal polyps are present. In this study, acoustic rhinometry has been used to assess the change in nasal cavity volume following intra-nasal polypectomy in 20 subjects. The volumes of the polyps removed surgically were measured by displacement and compared with the volume change recorded by acoustic rhinometry. A correlation of r = 0.59 (P= <0.01) has been obtained. Therefore, it is possible to apply acoustic rhinometry as a method of assessing non-surgical treatment of nasal polyps given certain conditions.  相似文献   
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A consecutive series of six adult patients ranging in age from 29 to 53 years is presented. The clinical and radiological features in each patient are described. Attention is drawn to the features demonstrated on computed axial tomography. In only one patient, the first encountered, was surgical excision undertaken and histological verification obtained. One patient died before any form of treatment could be instituted. The remaining four patients were treated with antituberculous chemotherapy alone and their progress monitored by sequential computed tomography. The excellent response and good outcome in this conservatively treated group are documented.  相似文献   
74.
Study Objective: To compare the volatile anesthetic sevoflurane with halothane, enfurane, and isof urane on the uptake and biotransformation in humans.

Design: Prospective pharmacokinetic study of sevofurane administration in human subjects.

Setting: Inpatient surgery clinic at a university medical center.

Patients: Thirty-two Japanese patients, free of systemic diseases, undergoing minor elective surgery with endotracheal general anesthesia.

Interventions: The patients were assigned randomly to one of four groups: halothane, enflurane, isofurane, or sevofurane. One of the four volatile anesthetics being investigated [equivalent to 1.1 minimum alveolar concentration (MAC): halothane, 0.85%; enfurane, 1.85%; isofurane, 1.27%; and sevofurane, 1.88%; in inspired concentrations throughout the first hour of anesthesia] was administered for 60 minutes.

Measurements and Main Results: In all patients, serum and urinary fluoride concentrations were measured. The concentrations of all gases were measured separately with a mass spectrometer. The cumulative uptake of each anesthetic agent during a certain period was calculated as an integration of the uptake rate per minute. The results for one-hour inhalation of sevofurane (1.1 MAC) showed an uptake (corrected for body surface area and MAC) of 490 ml/m2/MAC and estimated degradation rate of 3.3%. For purposes of comparison, similar studies of halothane (uptake, 653 ml/m2/MAC; degradation rate 15.7%), enfurane (1150 ml/m2/MAC; 1.3%), and isofurane (439 ml/m2/MAC; 0.6%) were also conducted. Sevofurane had a peak serum inorganic fluoride concentration of 19.3 μmol/L, and no abnormality in hepatic or renal functions was observed in any of the subjects during the two weeks postoperatively.

Conclusions: Accurate determinations of uptake and degradation rate for sevoflurane and three other volatile anesthetics in Japanese patients were obtained. These findings have established that, despite its relatively large MAC *1.71%), sevoflurane has a small uptake due to its low solubility. However, the degradation rade was shown to be as high as 3.3%, resulting in a higher serum fluoride concentration than seen after administration of isoflurane, halothane, and (possibly) enflurane.  相似文献   

75.
Gastrointestinal involvement in von Recklinghausen's disease occurs in three principal forms: hyperplasia of the submucosal and myenteric nerve plexuses and mucosal ganglioneuromatosis which leads to disordered gut motility; gastrointestinal stromal tumours showing varying degrees of neural or smooth muscle differentiation; and a distinctive glandular, somatostatin-rich carcinoid of the periampullary region of the duodenum that contains psammoma bodies and which may be associated with phaeochromocytoma. This review describes the histopathological features of these lesions and discusses potential pitfalls in their differential diagnosis. Their accurate identification has significant implications for clinical management and may even provide the first pointer to the diagnosis of neurofibromatosis.  相似文献   
76.
Antigenic diversity of the asexual developmental stages of Eimeria tenella   总被引:2,自引:1,他引:1  
Total polypeptides from unsporulated and sporulated oocysts, sporozoites and the first two generations of merozoites of Eimeria tenella were fractionated by electrophoresis through polyacrylamide gels. The parasites are complex and the arrays of polypeptides differ for each of the developmental stages indicating that there is stagespecific control of gene expression. In particular, first generation merozoites display a markedly different polypeptide profile to that of either sporozoites or second generation merozoites. Changes in antigenicity during sporulation and the antigenic relationships between the three asexual zoite stages were examined by probing electroblotted polypeptides with a panel of antisera raised in rabbits to purified preparations of each stage. Antigenic cross-reactivity is well maintained throughout sporulation even though the sizes of antibody-reactive polypeptides change. In contrast there is a marked lack of cross-reactive epitopes between sporozoites, first and second generation merozoites.  相似文献   
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79.
In this article we present a patient with acute lymphoblastic leukemia (ALL) associated with eosinophilia, in which the eosinophilia preceded a meningeal and bone-marrow relapse of ALL. We analysed the purine and pyrimidine nucleotide content of the eosinophils (92% pure) and compared the nucleotide pattern with that of eosinophils from healthy donors and from patients with eosinophilia not associated with leukemia. The ratios of purine : pyrimidine and of uracil :cytosine nucleotides were decreased compared with those in eosinophils from healthy donors and from patients with eosinophilia with other aetiologies. The total nucleotide concentration was increased, especially the concentration of UDP-sugars and pyrimidine nucleotides.

The decrease in these ratios and the increase in concentration of the nucleotides and the UDPsugars were also detected in leukemic cells of patients with ALL (de Korte et al., Leukemia Res. 10, 389–396 (1986)) compared to normal lymphocytes. We suggest a malignant character of the eosinophils in our patient with ALL associated with eosinophilia, in contrast with the nonmalignant state suggested previously for these cells.  相似文献   

80.
Immunocytochemical localization of inhibin was carried out in paraffin embedded tissue sections of the control and antiprogestin (ZK 98.299)-treated bonnet monkey endometrium using polyclonal antibodies generated against human seminal plasma inhibin (10.5 kDa). The study shows that administration of low doses (5 mg/ week) of antiprogestin results in an increase in the expression of inhibin by the endometrium. Treatment with higher doses (20 mg/week) caused a decrease in the expression. Since treatment with higher doses also caused atropic changes in the endometrium, the decrease in inhibin could be the result of morphological damage to the endometrium rather than the effects of antiprogestin on the expression of inhibin. The potential involvement of endometrial inhibin in the process of nidation is speculated.  相似文献   
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