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551.
552.
Photochemotherapy using psoralen and ultraviolet (UV)A irradiation (PUVA) is a useful treatment method for vitiligo. However, long-term PUVA therapy may cause several adverse effects including skin cancer, especially squamous cell carcinoma (SCC). We describe a case of SCC in vitiligo lesion after long-term PUVA therapy.  相似文献   
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Hepatic technetium-99m-mebrofenin iminodiacetate (99mTc-mebrofenin IDA) scans and serum gamma-glutamyl transpeptidase (GGTP) have high sensitivity for extrahepatic biliary atresia (EHBA). This study was based on the hypothesis that the interpretation of results of 99mTc-mebrofenin IDA scans and serum GGTP levels in series would result in a reduction of the false positivity observed with these tests individually. The aetiology of neonatal cholestasis in 132 study patients was: 25% (33/132) EHBA, 45.5% (60/132) neonatal hepatitis (NH) with an identifiable cause and 19.7% (26/132) idiopathic NH. Of the various clinical, biochemical and imaging parameters that were significantly different between patient groups, sensitivity for EHBA was: serum GGTP > or = 150 IU l(-1) (100%), 99mTc-mebrofenin IDA scans (100%), pale stools (82.8%) and total serum bilirubin > or = 12 mg dl(-1) (66%). However, specificity ranged from 48.5 to 79%. Of the 63 patients who had non-excreting IDA scans, operative cholangiograms could be avoided on the basis of a specific aetiological diagnosis of NH, made concurrently, in only 9 infants. The rest (54) underwent operative cholangiograms; 21 (39%) of these had patent biliary trees and therefore underwent the procedure unnecessarily. If serum GGTP (< 150 IU l(-1)) had been used as a screen after IDA scanning in these 54 patients, operative cholangiograms could have been avoided in another 12 patients and thereafter only 9/42 (21%) of the operative cholangiograms would have been considered unnecessary. Conclusion: A diagnostic algorithm is proposed wherein serum GGTP level (at a cut-off level that maintains 100% sensitivity for EHBA) is used in series with non-excreting 99mTc-mebrofenin IDA scans (for patients with no specific aetiological label). This strategy reduces the false positivity of individual tests.  相似文献   
556.
The antioxidant, antifungal and antibacterial potentials of volatile oils and oleoresin of Cinnamomum zeylanicum Blume (leaf and bark) were investigated in the present study. The oleoresins have shown excellent activity for the inhibition of primary and secondary oxidation products in mustard oil added at the concentration of 0.02% which were evaluated using peroxide, thiobarbituric acid, p-anisidine and carbonyl values. Moreover, it was further supported by other complementary antioxidant assays such as ferric thiocyanate method in linoleic acid system, reducing power, chelating and scavenging effects on 1,1'-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals. In antimicrobial investigations, using inverted petriplate and food poison techniques, the leaf and bark volatile oils has been found to be highly effective against all the tested fungi except Aspergillus ochraceus. However, leaf oleoresin has shown inhibition only for Penicillium citrinum whereas bark oleoresin has caused complete mycelial zone inhibition for Aspergillus flavus and A. ochraceus along with Aspergillus niger, Aspergillus terreus, P. citrinum and Penicillium viridicatum at 6 microL. Using agar well diffusion method, leaf volatile oil and oleoresin have shown better results in comparison with bark volatile oil, oleoresin and commercial bactericide, i.e., ampicillin. Gas chromatographic-mass spectroscopy studies on leaf volatile oil and oleoresin resulted in the identification of 19 and 25 components, which accounts for the 99.4% and 97.1%, respectively of the total amount and the major component was eugenol with 87.3% and 87.2%, respectively. The analysis of cinnamon bark volatile oil showed the presence of 13 components accounting for 100% of the total amount. (E)-cinnamaldehyde was found as the major component along with delta-cadinene (0.9%), whereas its bark oleoresin showed the presence of 17 components accounting for 92.3% of the total amount. The major components were (E)-cinnamaldehyde (49.9%), along with several other components.  相似文献   
557.
目的观察脂多糖(LPS)对成纤维细胞基质金属蛋白酶(MMPs)及其抑制物金属蛋白酶组织抑制因子(TIMPs)表达的变化,探讨伤口感染时LPS对伤口愈合的可能影响。方法将体外培养的人成纤维细胞加入不同浓度的LPS(10、100、1000μg/ml后,用荧光标记的明胶酶谱法和反向酶谱法测定培养液中MMPs及TIMPs表达的变化,并用电泳分析软件对黑色条带(MMPs)或亮色条带(TIMPs)的面积及密度进行半定量分析。结果LPS可以上调成纤维细胞的MMP-2、TIMP-1和TIMP-2的表达,且TIMPs增加的程度大于MMPs。10、100、1000μg/ml的LPS使MMP-2分别增加为基值的1.3、1.7、1.6倍,TIMP-1分别为3、4.5、3.5倍,TIMP-2分别为3、6、5.6倍。结论LPS在伤口愈合过程中成纤维细胞表达MMPs和TIMPs的环节上,对伤口愈合没有明显的不利影响。  相似文献   
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PurposeIn this study, we are trying to find out viral aetiology in paediatric age group patients from 1 month to 15 years of age in Western Rajasthan region.MethodsA total of 105 patients from 1 month to 15 years were recruited into this study. CSF samples were collected and were processed by multiplex real-time PCR for detection of various predefined panels of viral agents. ELISA was also done for all samples for detection of dengue, JE, measles and mumps.ResultsA total of 32 samples out of 105 were tested positive for viral agents. Viral aetiology detected in this study were Adenovirus (n ?= ?2), EBV (n ?= ?1), HHV-1 (n ?= ?10), HHV-6 (N ?= ?5), Parechovirus (n ?= ?1), Parvovirus B19 (n ?= ?7), Dengue (n ?= ?2) and Measles (n ?= ?1). Mixed infections were also detected, HHV-1 and HHV-6 (n ?= ?2), HHV-1 and Parvovirus B19 (n ?= ?1). In 73 patients no viral aetiology could be detected.ConclusionsParvovirus B19 is sporadically prevalent in this geographical region. In this study, HHV-6 was also found which has not been reported earlier from India.  相似文献   
559.
目的:冷冻温度对制备性能优良的聚乙烯醇水凝胶有较大的影响,拟通过采用反复冷冻-融化方法制备聚乙烯醇水凝胶,探讨在不同冷冻温度下制备的聚乙烯醇水凝胶的物理性能和力学性能,寻求制备聚乙烯醇水凝胶的最佳冷冻温度。方法:实验于2007-04/06在中国矿业大学材料学院摩擦学与可靠性工程实验室完成。实验选用白色絮状的聚乙烯醇20-99作为原料,按一定比例将聚乙烯醇溶于去离子水中,在恒温水浴箱中于90℃下加热4h,配制成一定浓度的聚乙烯醇水溶液;然后将聚乙烯醇水溶液在超低温冷冻储存箱中冷冻成型,冷冻温度分别设为-10℃,-15℃,-20℃,-25℃,-30℃,冷冻时间为6~10h,取出试样后室温下融化2~4h,上述冷冻-融化过程重复3次制得聚乙烯醇水凝胶。实验选用聚乙烯醇的质量分数为15%,制备不同厚度的聚乙烯醇水凝胶试样若干备用。测试各种冷冻温度下制备的聚乙烯醇水凝胶的密度、含水率、再溶胀性和结晶度等物理性能以及弹性模量和应力松弛等力学性能。结果:聚乙烯醇水凝胶的物理性能和力学性能随冷冻温度的不同而明显变化;-20℃反复冷冻融化制备的聚乙烯醇水凝胶具有较好的物理性能和力学性能,其密度为1.06543g/cm3,含水率为82.61%,再溶胀率达238.8%,结晶度为74.03%,弹性模量为0.0974MPa。结论:-20℃是反复冷冻-融化法制备聚乙烯醇水凝胶的常选冷冻温度。  相似文献   
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