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1.
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  
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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Kuross  SA; Hebbel  RP 《Blood》1988,72(4):1278-1285
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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High serum fluoride (F-) in patients with chronic renal failure (CRF) and end-stage renal disease (ESRD) is associated with risk of renal osteodystrophy and other bone changes. This study was done to determine F- in normal healthy controls and patients with ESRD on haemodialysis (HD) or peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females) and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l) of F- content in drinking water. Control subjects showed a mean serum F- concentration of 1.08 +/- 0.350 microM/l. Males in control group showed slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F- concentration did not correlate significantly with age and sex among control subjects, whereas such correlation was observed in patients with ESRD on dialysis. Mean serum F- concentration was significantly higher in patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal controls. When grouped according to sex, the mean serum F- concentration in males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped according to age, it was observed that F- concentration was significantly higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated with age and sex, being higher in males and above 20 years. Despite appreciable clearance of F- (39-90%) across the peritoneum, patients on CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs 2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their serum F- concentration above 3.0 microM/l, posing the risk of renal osteodystrophy.   相似文献   
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本文详细介绍了在新疆发现的花蠕形蚤、叶氏蠕形蚤、北山羊蠕形蚤、羊长喙蚤和狍长喙蚤的形态学特点、地理分布和某些生物学特性。  相似文献   
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川芎嗪诱导大鼠骨髓间质干细胞分化为神经元样细胞的研究   总被引:26,自引:0,他引:26  
撒亚莲  李海标 《解剖学报》2003,34(5):514-517
目的用川芎嗪(ligustrazin hydrochloride)在体外定向诱导SD青年鼠骨髓间质干细胞(mesenchymal stem cells,rMSCs)分化为神经元样细胞。方法用低糖DMEM冲洗骨髓腔,收集骨髓细胞悬液,接种在塑料培养瓶中。经体外扩增、纯化,选用第5代后的骨髓间质干细胞进行诱导分化。用10μg/LbFcF预诱导24h,更换成含川芎嗪的无血清培养基DMEM诱导间质干细胞分化为神经元样细胞。用免疫组织化学SABC法鉴定神经丝蛋白(NF—M)、神经元特异性烯醇化酶(NSE)、巢蛋白(nestin)、微管联合蛋白-2(MAP-2)、生长相关蛋白-43(GAP-43)、胶质纤维酸性蛋白(GFAP)的表达。结果第5代间质干细胞形态达到均一,呈梭形。用川芎嗪诱导15min到3h,间质干细胞胞体逐渐增大,并伸出细长突起形似神经元样细胞。免疫组织化学显示NF-M、NSE、nestin、MAP-2和GAP-43表达阳性,而GFAP阴性。对照组上述染色均为阴性。结论川芎嗪可诱导骨髓间质干细胞分化为神经元样细胞。  相似文献   
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