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51.
Effect of bischalcone derivative (2E,5E)-2,5-bis(4-hydroxy-3-methoxybenzylidene) cyclopentanone (CA) on blood glucose level and lipid profile was investigated in normoglycemic and streptozotocin (STZ)-induced diabetic rats. In oral glucose and sucrose tolerance test, treatment with CA (25 mg/kg) and glidenclamide (10 mg/kg) significantly improved the glucose and sucrose tolerance in normal animals. In addition, respective treatment for 7-day resulted in significant percentage reduction in serum glucose (SG). In standardized STZ-induced diabetic rats, a single dose of CA treatment exhibited reduction in SG levels at different time intervals compared to basal levels. The lipid profile levels are restored to near-normal value of all tested parameters. The compound CA was docked into the active site of 5′-AMP (adenosine monophosphate)-activated protein kinase (PDB ID: 2OOX). The binding and docking energy were found to be ?6.9 and ?45.1 kcal/mol, respectively.  相似文献   
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53.
Purpose:To evaluate the clinico-microbiological profile, donor cornea risk factors, and outcomes of postkeratoplasty endophthalmitis at a tertiary care center.Methods:Retrospective analysis of charts of 28 consecutive patients (28 eyes) of acute endophthalmitis following either an endothelial keratoplasty (EK) or an optical penetrating keratoplasty (PK) surgery, performed between 2006 and 2018 (13-year period). Positive microbiology, identification and classification of predisposing factors, surveillance of utilized paired donors, treatment outcomes, and differences in the rate and severity of the event between optical penetrating and endothelial keratoplasty.Results:The estimated incidence of endophthalmitis was 0.23% in the entire cohort; it was 0.34% and 0.15%, after EK and PK, respectively (P = 0.049). The median time of endophthalmitis was 4.5 days postsurgery. Donor-related endophthalmitis was recognized in 7/28 (25%) eyes. Culture positivity was 68% (n = 19 of 28). Bacteria was isolated in 84% (n = 16 of 19) instances; Gram-negative bacilli were more common (87.5%; 14 of 16), and Pseudomonas species (50%; 7 of 14) was the most common Gram-negative bacterium. Majority (>75%) of the Gram-negative bacteria were resistant to all fluoroquinolones, aminoglycosides, 3rd generation cephalosporins, and meropenam; 1/3rd were resistant to imipenem; and 90% were sensitive to colistin. Treatment included intraocular antibiotic injections (96.4%), vitrectomy (42.9%), and therapeutic keratoplasty (50%). In 85.7% (24 of 28), globe was salvaged. The final vision was 20/200 or better in 39.1% (9 of 23) eyes.Conclusion:EK carried a higher risk of endophthalmitis than PK in this cohort. Bacterial infection was more common in this series, with Gram negative bacilli being the commonest organisms. Multidrug resistance was common (~75%) in Gram negative isolates.  相似文献   
54.
A retrospective analysis of 127 surgically treated cases of T-1, T-2 carcinoma of oral tongue during the period 1987-1990 was undertaken. 68.5 per cent (87) underwent hemiglossectomy and 31.5 per cent (40) underwent wide excision. There were loco-regional recurrences in 22 per cent (27). In the hemiglossectomy group 9 per cent (8 of 87) had local recurrences compared to 25 per cent (10 of 40) of wide excision group, (P = 0.01). Mean disease free survival was 40 months and 33 months for hemiglossectomy group and wide excision group respectively, (P = 0.006). It is seen that local recurrences are significantly less for the hemiglossectomy group compared to the wide excision group.KEY WORDS: Disease free survival, Early cancer, Recurrence, Surgery, Tongue  相似文献   
55.
空气喷磨和酸蚀与树脂突超微结构的关系   总被引:2,自引:0,他引:2  
目的 体外评价5种处理方法对树脂突超微结构的影响。方法 对照组:对1颗离体磨牙常规预防性树脂充填。其余4颗磨牙用空气喷磨处理,分别用50μ和27μ氧化铝微粒,酸处理其中2颗磨牙。窝洞用复合树脂充填后,用10%盐酸溶解牙釉质,扫描电镜观测树脂突超微结构。结果 对照组呈典型窝状结构。空气喷磨的树脂突呈不规则结构,结合酸蚀的树脂突表面更加粗糙。结论 空气喷磨具有一定的蚀刻作用但不如酸蚀作用强。  相似文献   
56.
AIM To study the clonality of the esophageal carcinosarcoma by using molecular approaches.METHODS Two esophageal carcinosarcomas were included in the study. Tumor area from dysplasticlesion, squamout cell carcinoma, basaloid cell carcinoma and spindle cell elements were microdissectedseparately. Each element was analyzed with 14 microsatellite markers and direct sequenced for p53 gene andras gene mutation.RESULTS Both tumors displayed a typical histologic feature of carcinosarcoma. Both cases showed thedivergent differentiation by immunohistochemistry study. In case 1 the identical LOH at p53 and hMLH1 lociwas detected. The heterogenous LOH was detected only in carcinosarcoma at RB1 and BRCA1 loci, whilethe LOH at ACTC locus was seen only in sarcoma. The same mutation of the splice site of exon 6-intron 6displayed in the two tumor elements. In case 2, a coordinate LOH at RB locus was demonstrated in threetypes of tumor elements: sqamous carcinoma, basaloid carcinoma and spindle cell element. A heterogenousLOH was seen only in spindle cells at TAP1 locus. No mutation in exon 5-8 of p53 gene has been found incase 2. No mutation of K-ras gene was found.CONCLUSION Although the different differentiation, the two elements of esophageal carcinosarcoma mayhave a single clonality. The p53 gene mutation occurred before the two differentiation directions switched.The distinct molecular genotype can be determined through molecular biological analysis. The microsatelliteprofiling can serve as an approach to find out which genetic alteration occurs before or after thedifferentiation is determines.  相似文献   
57.
冠状动脉狭窄的16层螺旋CT造影检查   总被引:4,自引:1,他引:3  
目的以常规X线冠状动脉造影为标准,评价16层螺旋CT(MSCT)无创性检查冠状动脉及诊断冠状动脉狭窄的价值。资料与方法65例临床初诊为冠心病,无冠状动脉成形术和搭桥术史的患者,在冠状动脉16层MSCT造影检查后,回顾性重建心电门控轴位图像,并采用容积成像(VR)、多平面重建(MPR)、曲面MPR、最大密度投影(MIP)等后处理方法,对所有冠状动脉及其分支进行重建,统计可供临床评价的、管径≥1.5mm的冠状动脉段,以选择性冠状动脉造影(SCA)为标准,对比分析MSCT诊断冠状动脉显著性狭窄(管腔平均直径缩小超过50%)的准确性。其中8例在检查前心率超过80次/min的患者使用了B受体阻滞剂。结果93%的冠状动脉节段和94%的冠状动脉主干可供评价,不能评价的主要原因分别为:心脏运动伪影(58%),致密钙化(28%)和管腔显影不良(14%)。除外不能评价的冠状动脉,按节段和主干分类,MSCT诊断冠状动脉显著性狭窄的敏感性和特异性分别达到92%、98%和95%、97%。结论无需常规使用B受体阻滞剂,16层MSCT冠状动脉造影即可获得较好的图像质量用于诊断冠状动脉狭窄,是一种值得临床医师信赖的检查冠状动脉有无狭窄的非创伤性方法。  相似文献   
58.
A series of 1,3,5-triaryl-2-pyrazolines 2ag were synthesized by the reaction of 4,4′-disubstituted chalcone with phenyl hydrazine. All these compounds were characterized by NMR, IR and mass spectral and single crystal XRD data. All the synthesized products were screened for their in vitro antimicrobial, analgesic and antioxidant properties. The docking studies were carried out for these compounds against the active site of methionyl-tRNA synthetase (metRS). Some of the tested compounds exhibited significant antimicrobial, analgesic, DPPH scavenging activities and molecular binding.  相似文献   
59.
This work reports the cyclic voltammetric, modulatory effect on oxidative stress markers against radiation induced oxidative stress in E. coli bacteria and antiviral activities of two bischalcone derivatives (2E,5E)-2,5-bis(3-methoxy-4-hydroxy-benzylidene)-cyclopentanone (B1) and (2E,5E)-2,5-bis(4-fluorobenzylidene)-cyclopentanone (B2). The reducing ability of B1 and B2 was determined by cyclic voltammetry. The anodic peak current i pa and anodic peak potential Epa of B1 and B2 were ?154.7, ?99?μA, and ?0.15?V, 0.0125?V, respectively. The low anodic current and low anodic peak potential imply the good reducing ability of the molecules. The radioprotective effect of bischalcones was studied by gamma radiation induced oxidative stress in E. coli K12 at 0.2 and 0.4?Gy. The bacteria samples treated with B1 and irradiated showed diminished level of TBARS, an oxidative stress marker. The levels of SOD and CAT antioxidant enzymes were brought to near basal level for B1 treated and irradiated bacteria with respect to the control. The protective effect of the bischalcone derivatives against radiation was further supported by determining colony forming units (CFU) of bacteria in pre- and post-irradiated samples. Further, B2 showed 73.69% of inhibition of buffalopox virus and camelpox virus.  相似文献   
60.
Revision knee arthroplasty for infection poses a treatment challenge. The presence of massive osteolysis limits the treatment options in this cohort. Controversy exists in the management of these patients. Direct exchange arthroplasty has provided good results in the presence of infection, but whether this is appropriate in the presence of massive bone defects associated with the infection is undetermined. We present our experience in revision knee arthroplasty for infection associated with massive bone defects. The aim of the study is to present the preliminary results of a direct exchange endoprosthetic reconstruction with tumour prosthesis for periprosthetic infection associated with segmental bone defects. This is a retrospective study of prospectively collected data, involving six patients with periprosthetic infection and massive bone defects treated by direct exchange tumour prostheses between 2003 and 2007 (four distal femoral replacements and two total femoral replacements). The mean age and follow-up were 74.2 (±5.2) years and 32.5 (±8.2) months respectively. Each patient had an infected revised knee arthroplasty at the time of referral to our institution. Staphylococcus aureus was the most common causal organism. The mean duration of antibiotics was 6 weeks intravenous therapy followed by 3.5 months oral. The recurrences of infection, pain or immobility were outcome criteria considered failures. Our success rate was 80%. Salvage of infected revised knee arthroplasty by direct exchange endoprosthetic reconstruction has provided an effective means of pain relief, joint stability and improved mobility in our cohort. It reduces morbidity through earlier mobilisation and avoids a second major operation.  相似文献   
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