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舌黏膜尿道成形治疗尿道狭窄的初步报告 总被引:3,自引:0,他引:3
目的:探讨舌黏膜补片法尿道成形治疗尿道狭窄的疗效。方法:采用舌黏膜尿道成形治疗尿道狭窄14例。尿道狭窄段3.5~14cm,平均6.2cm;术前耻骨上膀胱造瘘8例,余6例排尿均较为困难,最大尿流率2.5~5.5ml/s,平均3.8ml/s。结果:术后随访2~8个月,1例因伤口感染致尿道皮肤瘘,余患者均排尿通畅,最大尿流率增至22~51ml/s,平均29.6ml/s。结论:舌黏膜具有取材方便、对患者创伤小、抗感染力强等特点,是一种较好的尿道替代物,尤其适合尿道狭窄段<6cm的患者。 相似文献
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Suppurative corneal ulceration in Bangladesh 总被引:8,自引:0,他引:8
AAS Dunlop MB BS ED Wright MRCPath † SA Howlader‡ I Nazrul‡ R Husain‡ K McClellan FRACO § FA Billson FRACO § 《Clinical & experimental ophthalmology》1994,22(2):105-110
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season. 相似文献
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The axillary arch is reported to occur in 7% of the population, but in our experience has only been observed in 0.25%. The anatomical features are described and its importance in axillary dissection is indicated. In addition, its relevance to the prevention of lymphoedema and to the construction of latissimus dorsi flaps is discussed. The axillary arch should be considered in the differential diagnosis of axillary swellings. 相似文献
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Nonheme iron in sickle erythrocyte membranes: association with phospholipids and potential role in lipid peroxidation 总被引:5,自引:0,他引:5
Previous studies documented the abnormal association of heme and heme proteins with the sickle RBC membrane. We have now examined RBC ghosts and inside-out membranes (IOM) for the presence of nonheme iron as detected by its formation of a colored complex with ferrozine. Sickle ghosts have 33.8 +/- 18.2 nmol nonheme iron/mg membrane protein, and sickle IOM have 4.3 +/- 3.0 nmol/mg. In contrast, normal RBC ghosts and IOM have no detectable nonheme iron. The combination of heme and nonheme iron in sickle IOM averages nine times the amount of membrane- associated iron in normal IOM. Kinetics of the ferrozine reaction show that some of this nonheme iron on IOM reacts slowly and is probably in the form of ferritin, but most (72% +/- 18%) reacts rapidly and is in the form of some other biologic chelate. The latter iron compartment is removed by deferoxamine and by treatment of IOM with phospholipase D, which suggests that it represents an abnormal association of iron with polar head groups of aminophospholipids. The biologic feasibility of such a chelate was demonstrated by using an admixture of iron with model liposomes. Even in the presence of tenfold excess adenosine diphosphate, iron partitions readily into phosphatidylserine liposomes; there is no detectable association with phosphatidylcholine liposomes. To examine the bioavailability of membrane iron, we admixed membranes and t-butylhydroperoxide and found that sickle membranes show a tenfold greater peroxidation response than do normal membranes. This is not due simply to a deficiency of vitamin E, and this is profoundly inhibited by deferoxamine. Thus, while thiol oxidation in sickle membranes previously was shown to correlate with heme iron, the present data suggest that lipid peroxidation is related to nonheme iron. In control studies, we did not find this pathologic association of nonferritin, nonheme iron with IOM prepared from sickle trait, high-reticulocyte, postsplenectomy, or iron-overloaded individuals. These data provide additional support for the concept that iron decompartmentalization is a characteristic of sickle RBCs. 相似文献
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Extreme bradycardia during sleep apnea caused by myxedema 总被引:1,自引:0,他引:1
A 52-year-old man with myxedema was evaluated for anterior chest pain that was considered to be compatible with myocardial ischemia. The night after admission he developed extreme bradycardia, hypotension, and apneic episodes lasting up to 25 s. Continuous positive airway pressure and administration of medroxyprogesterone acetate prevented further episodes and relieved much of the somnolence and lethargy that had contributed to the evidence for myxedema. Alveolar hypoventilation caused by decreased sensitivity to carbon dioxide, inadequate central neural drive, peripheral muscle force, and obesity all may have contributed to the apnea. Chest pain has not recurred, and results of electrocardiography have remained normal following full thyroid hormone replacement. The early recognition of myxedema causing sleep apnea will allow specific treatment to avoid the cardiovascular risks related to prolonged apnea and will help avoid confusion with other etiologies of cardiovascular abnormalities. 相似文献