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101.
Middle ear effusion has been considered the most common cause of vestibular disturbance in children. However, there have been only a few studies on vestibular disturbance in children with otitis media with effusion. We studied the vestibular systems of 30 children with otitis media with effusion aged 8 to 13 years and compared the results with 15 age- and sex-matched controls. A questionnaire relating to vestibular disturbance was given to patients and their parents. Spontaneous nystagmus and positional nystagmus were recorded by electronystagmography as diagnostic tests of the vestibular system. Romberg's and past-pointing tests were performed on children with otitis media with effusion and controls. After vestibular tests were completed, myringotomy was performed, and a ventilation tube was inserted. The questionnaire and the vestibular tests were repeated after the operation and during the first month after surgery. Our study showed that there was a history of vestibular disturbance in 33% of children with otitis media with effusion. Electronystagmography and Romberg's test findings demonstrated that 33% of the children had vestibular dysfunction (p < 0.05). After myringotomy with ventilation tube insertion, vestibular test results returned to normal, and symptoms related to vestibular disturbance improved. These findings confirm the assumption that middle ear effusion may affect the vestibular system, which can be resolved after myringotomy with ventilation tube insertion.  相似文献   
102.
Our study describes a newly designed stapedotomy prosthesis which consists of two components: (1) a platinum ribbon, and (2) a Teflon shaft. The first innovation is a flattened 'tab' on the posterior aspect of the platinum ribbon. The second innovation concerns the dual diameter cylinder-like shaft. Our prosthesis was implanted into 25 individuals, who underwent stapedotomy for stapes fixation, and the results are shown and discussed. Our innovations offer a proper and safe insertion of the prosthesis into the oval window associated with excellent manipulation and handling. At the same time, maximum visualization of the surgical field is achieved, while the stepped-down design of the shaft prevents the prosthesis protruding into the vestibule.  相似文献   
103.
104.
PURPOSE: To demonstrate that vasoactive intestinal peptide (VIP), a 28-amino acid neuropeptide, is a growth factor of human trabecular meshwork (TM) cells in culture and in a corneoscleral explant organ culture treated with laser trabeculoplasty (LTP). METHODS: Proliferating human TM cells in cell cultures were incubated with VIP for 20 hours, followed by total cell number determination, using a Coulter counter. The percentage of proliferating TM cells was assessed, using an antibody against the proliferating cell nuclear antigen (PCNA). To test the growth effect of VIP on TM cells in situ, corneoscleral explants in organ cultures were first treated with argon LTP to initiate TM-cell proliferation and then were exposed to VIP for 48 hours. The mitotic TM cells were demonstrated immunocytochemically, using anti-PCNA in paraffin sections of the explants; and the total number of TM cells was determined after paraffin sections were counterstained by hematoxylin. RESULTS: Vasoactive intestinal peptide dose-dependently stimulated the proliferation of TM cells in cell culture. Treatment with 5 x 10(-10) M VIP resulted in a maximal increase of 40% in cell number. The effect of VIP was blocked by a VIP antagonist. The number of PCNA-stained TM cells and the total cell number in the TM in LTP-treated corneoscleral explants were increased by VIP. CONCLUSIONS: Exogenously applied VIP stimulated the proliferation of human TM cells in subconfluent cultures and in LTP-treated corneoscleral explants. In that LTP has been shown to increase the number of TM cells in situ, the growth stimulatory effect of VIP may help enhance this therapy.  相似文献   
105.
An estimated third of rheumatologists send aspirated synovial fluid samples for culture routinely during the course of management of their patients irrespective of the underlying diagnosis. This is done apparently even when sepsis is not suspected. This audit of 507 synovial fluid culture requests revealed that positive bacterial growth was rare even when sepsis was queried on the request forms but none was positive in any of the routine samples. Our findings throw doubt on the value of routine synovial fluid culture. We recommend that such cultures are undertaken when infection is a possibility and in immuno-compromised patients. An average health district would save pounds 3000 per annum if such a policy was adopted, but across the National Health Service as a whole the total expenditure saved on this unnecessary investigation would be considerable.  相似文献   
106.
OBJECTIVE: It has been shown recently that 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) is expressed as at least 2 isozymes. In the liver, 11 beta-HSD1 converts cortisone to cortisol; in the kidney, 11 beta-HSD2 converts cortisol to cortisone. Conventional assessment of 11 beta-HSD activity in vivo has relied on gas chromatographic measurement of the ratios of conjugated cortisol and cortisone metabolites. However, these do not permit distinction between the tissue-specific activities of the enzymes and do not reflect all forms of 11 beta-HSD deficiency. In this report, we have assessed the usefulness of measuring unconjugated cortisol metabolites and free cortisol and cortisone in urine as indices of renal 11 beta-HSD activity in man. DESIGN: Six healthy male subjects established in sodium balance were given either glycyrrhetinic acid (170 mg t.d.s., to inhibit 11 beta-HSD2), carbenoxolone (100 mg t.d.s., to inhibit both 11 beta-HSD1 and 11 beta- HSD2) or both inhibitors in combination. MEASUREMENTS: Urinary electrolytes were measured and the concentrations of total and unconjugated urinary cortisol and its metabolites were determined by gas chromatography mass spectrometry. RESULTS: Glycyrrhetinic acid and carbenoxolone inhibited renal 11 beta-HSD2 to a similar degree, as judged by similar sodium retention. As previously reported, conventional measurement of ratios of total cortisol to cortisone metabolites were influenced to a greater extent by glycyrrhetinic acid (100-200% increase in ratio from baseline) than by carbenoxolone (< 30% increase). However, the effect of carbenoxolone was readily detected by measurement of urinary unconjugated cortisol/cortisone (130-480% increase of ratio from baseline) and also by measurement of ratios of unconjugated cortisol metabolites (60-130% increase). CONCLUSIONS: Measurement of free cortisol and cortisone in urine provides the most sensitive index of renal 11 beta-HSD activity. Measurement of total and conjugated urinary steroids is insensitive in circumstances where 11 beta-HSD activity in liver or elsewhere may be abnormal.  相似文献   
107.
We studied the cell kill induced by granulocyte-macrophage colony-stimulating factor (GM-CSF ) fused to Diphtheria Toxin (DT-GM-CSF ) in acute myeloid leukemia (AML) samples and in populations of normal primitive hemopoietic progenitor cells. AML samples from three patients were incubated in vitro with 100 ng/mL DT-GM-CSF for 48 hours, and AML cell kill was determined in a proliferation assay, a clonogenic assay colony-forming unit-AML (CFU-AML) and a quantitative long-term bone marrow (BM) culture ie, the leukemic-cobblestone area forming cell assay (L-CAFC). To measure an effect on cells with in vivo leukemia initiating potential DT-GM-CSF exposed AML cells were transplanted into immunodeficient mice. In two out of three samples it was shown that all AML subsets, including those with long-term abilities in vivo (severe combined immunodeficient mice) and in vitro (L-CAFC assay) were reduced in number by DT-GM-CSF. Cell kill induced by DT-GM-CSF could be prevented by coincubation with an excess of GM-CSF, demonstrating that sensitivity to DT-GM-CSF is specifically mediated by the GM-CSF receptor. Therefore, binding and internalization of GM-CSF probably occur in immature AML precursors of these two cases of AML. The third AML sample was not responsive to either GM-CSF or DT-GM-CSF. The number of committed progenitors of normal bone marrow (burst-forming unit-erythroid, colony-forming unit granulocyte- macrophage, and cobble stone area forming cell [CAFC] week 2) and also the number of cells with long-term repopulating ability, assayed as week 6 CAFC, were unchanged after exposure to DT-GM-CSF (100 ng/mL, 48 hours). These studies show that DT-GM-CSF may be used to eliminate myeloid leukemic cells with long-term potential in vitro and in immunodeficient mice, whereas normal hemopoietic stem cells are spared.  相似文献   
108.
109.
The author, a professor of nephrology, reports some impressions of his 7-year stay in Turkey. He worked at the Ege University in Izmir, traditionally one of the most 'western' cities. He and his wife, who gave unpaid assistance to dialysis patients, attempted to integrate into Turkish society as fully as possible. They traversed the country in weekends and holidays and introduced as many Dutch guests as they could to the unique archeological treasures, the magnificent nature and the extremely friendly population. Work at the university focused increasingly on cultivating a critical attitude with regard to the self, society and the trends and commercialization of medicine in Turkey and in the rest of the world. Self-reliance, also, had to be strengthened. Although this contravened the authority-based Turkish educational system, the efforts were clearly appreciated and even stirred enthusiasm in many of the younger people. There is no doubt that a foreign worker is regarded much more favourable in Turkey than in the Netherlands.  相似文献   
110.
The aim of this study was to determine the effect of subgingival scaling and root planing on healing of the distal surface of second molars following extraction of third molars. Twenty-eight patients with contralateral erupted third molars and pocket depths greater than or equal to 3 mm on the distal surface of the second molars participated in this study. Measurements of supragingival bacterial plaque, bleeding on probing, pocket depth, and relative attachment level were performed at baseline and 2 months after treatment. Extraction of contralateral third molars was carried out simultaneously. The experimental site received thorough scaling and root planing of the distal surface of the second molar, while the control site received extraction alone. Experimental sites showed significant improvement in all clinical parameters assessed compared to the control sites. In conclusion, periodontal lesions on the distal of second molars can be significantly improved following scaling and root planing after extraction of third molars.  相似文献   
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