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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   
3.
BACKGROUND AND OBJECTIVE: The use of cold air cooling (CAC) and cryogen spray cooling during dye laser treatment of port-wine stains (PWS) has become a standard in recent years. Still unsolved is the question of which fluences are necessary in combination with CAC in order to achieve an optimum clearance and the lowest possible rate of side-effects. STUDY DESIGN: In a prospective study, we treated 11 patients with PWS with pulsed dye laser (Photogenica V, Cynosure, lambda = 585 nm, iota(p) = 0.5 ms, spot size = 7 mm). Each PWS was partitioned into three areas: (area 1) 6 J/cm(2) without CAC, (area 2) 6 J/cm(2) with CAC (level 4), (area 3) 9 J/cm(2) with CAC (level 4). RESULTS: Area 3 (mean, 59%) showed a slightly better clearance than area 1 (mean, 57%); in area 2, we observed a reduced clearance (mean, 45%). Compared with area 1, we achieved a reduction of pain through CAC in areas 2 and 3. The healing periods as well as the rate of side-effects were comparable in all areas. CONCLUSION: We observed a slight but not statistically relevant increase in clearance with the use of higher fluences and CAC compared with lower fluences without CAC. Because pain is lowered significantly when using CAC, and because this makes the treatment more comfortable for the patients, we tend to recommend the use of higher fluences (9 J/cm(2)) with simultaneous CAC for treating PWS.  相似文献   
4.
We report on a male patient with Pick disease who had shown severe white matter atrophy and dilatation of the lateral ventricle in the frontal lobe from an early stage. Upon admission to our hospital 2 years after disease onset, the patient showed apathy, and MRI revealed severe atrophy of the cortex and white matter of the frontal lobe. He died at age 74, 11 years after disease onset. Autopsy revealed severe atrophy of the frontal and temporal lobes, severe loss of white matter in the frontal lobe, dilatation of the lateral ventricles, and cortical thinning. Histopathological examination showed severe loss of myelinated fibers in the frontal white matter and severe neuronal loss with gliosis in the frontal and temporal cortices. Many Pick bodies were seen. Our patient had a rare case of Pick disease predominantly affecting the frontal lobe with severe involvement of the white matter from an early stage. This case suggests that myelinated fibers in the white matter as well as cerebral neurons are primarily affected in Pick disease.  相似文献   
5.
对114例不同类型和级别的结肠癌进行银染核仁形成区嗜银蛋白(Ag-NORs)形态定量研究.结果表明,Ag-NORs数量、大小和分布在结肠未分化癌和印戒细胞癌组与管状腺癌和粘液腺癌组比较,有明显差异.管状腺癌随分化程度的降低,Ag-NORs的数量、形态、大小和分布也发生等级性变化.结果提示,Ag-NORs形态定量的数量、形态、大小和分布4项指标对结肠癌分型有一定意义,对管状腺癌分级有较好的诊断价值。  相似文献   
6.
AStudyonUsingImprovedMethenamine-silverStaintoDiagnosisofPneumocystiscariniiChenXiwei(陈锡慰)(DepartmentofParasitology,NanjingMe...  相似文献   
7.
本文用免疫荧光法与 Giemsa 氏法检测明显沙眼患者,两法阳性率相差无几。但在临床肉眼观察认为正常时,其阳性率分别为24.77%及11.58%(P<0.05),差异有显著意义,表明免疫荧光法检测早期沙眼较 Giemsa 氏法敏感。临床认为正常眼,经实验室检查25.56%为阳性,说明开展沙眼的实验室诊断是必要的。  相似文献   
8.
Abstract Until recently, the few available chlorhexidine mouthrinse products have been 0.2% formulations. However, concentrations of 0.12% chlorhexidine appear as effective as 0.2%, if the volume of the rinse is increased to 15 ml. Since the mere incorporation of chlorhexidine in a formulation does not guarentee availability of the antiseptic, it would seem reasonable to evaluate or compare all products. This is particularly the case when other ingredients, such as fluoride are added. The 1st study compared the effect of a 0.12% chlorhexidine rinse with a 0.12% chlorhexidine/0.022% sodium fluoride rinse for effects on plaque re-growth. The study was a 7-day, blind, randomised, 2-cell cross-over design with a baseline control run in period, in which 18 subjects participated. Both chlorhexidine products significantly reduced plaque compared to control but the chlorhexidine fluoride rinse was less effective than the chlorhexidine only rinse. The 2nd study assessed the propensity of the chlorhexidine rinses to induce dietary staining in vitro. For the chlorhexidine fluoride rinse, this was less than the other 0.12% rinse and a commonly used 0.2% product. The data in vivo and in vitro suggest reduced chlorhexidine availability from the chlorhexidine fluoride product which appears to cause some loss of efficacy.  相似文献   
9.
中枢性神经细胞瘤:17例临床病理分析   总被引:2,自引:0,他引:2  
背景与目的:中枢性神经瘤是少见的中枢神经系统肿瘤。为了提高对该病的认识、减少误诊率.我们结合文献复习,对患者的临床症状、影像学、病理改变及预后进行了研究讨论。方法:复习中国人民解放军总医院1970-2000年收治的中枢性神经瘤病例共17例,对患者的临床症状、影像学、病理改变及预后进行了回顾性研究。结果:中枢性神经细胞瘤发病率占同期原发性中枢神经系统肿瘤的0.14%。患者男10例,女7例.年龄从11岁-51岁不等,平均年龄32.7岁。肿瘤均位于脑室系统,7例位于透明隔位于侧脑室及三脑室者各5例。手术全部切除7例,部分切除10例,术后放疗者9例。9例进行了长期随访无复发迹象。另外,17例行免疫组化及2例行电镜检查,显示肿瘤呈神经元分化,仅4例局部表达GFAP;所有病例均无恶性组织学迹象,4例已做Ki-67免疫组化的阳性细胞〈2%。结论:综合上述及结合文献我们认为大多数中枢性神经细胞瘤是预后良好的肿瘤,部分预后较差,增加GFAP的阳性表达、细胞增殖指数的增加以及血管的增生可能提示较差的预后。手术切除为治疗该肿瘤的较好方法。对部分切除的病例、组织学呈间变改变的病例(细胞的异形性、核分裂像增加、血管内皮细胞增生及坏死)以及增殖指数增加者应辅以放疗。  相似文献   
10.
Backspatter from experimental close-range shots to the head   总被引:1,自引:0,他引:1  
Backspatter is the ejection of biological material from a gunshot entrance wound against the line of fire. This phenomenon was investigated experimentally in transverse gunshots to the heads of calves (n = 9) using two types of 9 mm Parabellum ammunition from shooting distances of 0–10 cm. The resulting bloodstains were documented on white paper placed horizontally 60 cm below the impact site. In this report the analysis was restricted to stains with a diameter > 0.5 mm. Backspatter was documented after every gunshot. The number of stains varied from 31–324 per gunshot and appeared to be independent of the shooting distance. The maximum distance droplets travelled varied from 72–119 cm. The majority of droplets accumulated between 0 and 50 cm. The number of droplets and the distances travelled should be higher in man for anatomical reasons. The direction a single droplet can take comprises every possible angle between the most tangential ones to the skin surface. This resulted in a semi-circle of 180° covered with stains. Skin ruptures of the entrance wound were not observed. The succession of events was documented on high speed film and started with the recoil of the firearm, immediately followed by a blow-out effect of the skin. Large droplets exited approximately 0.7–4 ms after the bullet impacted the skin. The calculated minimum initial velocity of these droplets was 13–61 m/s. Backspatter from gunshots to the head likely is caused by the hot gases expanding subcutaneously and by cavitation-related intracranial overpressure and tail splashing. In three out of nine gunshots, secondary backspatter additionally occurred as a result of droplets produced by a stream of blood from the entrance wound impacting the paper surface.  相似文献   
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