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181.
JM Palefsky M-E Penaranda LT Pierik LA Lagenaur LA MacPhail D Greenspan JS Greenspan 《Oral diseases》1997,3(Z1):S171-S176
Hairy leukoplakia (HL) is a lesion found on the side of the tongue of immunocompromised individuals, including those with human immunodeficiency virus (HIV) infection. The lesion has unique histopathologic features and is characterised by high-level Epstein-Barr virus (EBV) replication, multiple EBV strains, and extensive inter-and intra-strain recombination. Expression of EBV genes spanning the entire viral life cycle from latency-associated genes to late, replicative genes has been detected in the lesion. HL thus provides a unique opportunity to study EBV expression in oral epithelium, and to study expression of novel EBV genes. We therefore constructed a cDNA library from an HL biopsy and detected expression of two genes not previously described in vivo: BMRF-2 and BDLF-3. Sequence analysis of the cDNAs revealed few amino acid changes from the B95-8 sequence. Expression of both genes was localized to the lower prickle cell layer of the tongue epithelium. BMRF-2 protein expression was primarily detected in the cell nuclei of the upper prickle cell layer. BDLF-3 protein expression was observed in the perinuclear space and Golgi compartment. The function of these proteins is currently under investigation. 相似文献
182.
Objective
The purpose of this study was to determine if the exotic venomous species, Pterois volitans (lionfish) had reached as far south as St Vincent in the Caribbean. This predatory marine fish has successfully invaded the waters of the Western Atlantic and the Caribbean. Such success as an exotic invasive species is rare for a predatory marine fish. It is possible that the fish are growing larger and spreading faster than anticipated, thanks to a lower burden of parasites and a paucity of natural predators in their new environment. But prior to this report, no sightings of this species this far south had been reported.Methods
The authors conducted a search along with the help of local divers and fishermen in the waters of St Vincent.Results
Approximately one year after the initiation of the search, a juvenile specimen was positively confirmed and captured off the southern coast of St Vincent.Conclusions
The exotic predatory and venomous red lionfish, Pterois volitans, has successfully invaded marine waters as far south as the Windward Islands. Fishermen in these regions should be aware of this venomous species in the region and physicians must be aware of how to manage stings from such animals. 相似文献183.
184.
185.
Daniels AB Liu GT Volpe NJ Galetta SL Moster ML Newman NJ Biousse V Lee AG Wall M Kardon R Acierno MD Corbett JJ Maguire MG Balcer LJ 《American journal of ophthalmology》2007,143(4):635-641
PURPOSE: Obesity and weight gain are known risk factors for idiopathic intracranial hypertension (IIH; or pseudotumor cerebri). The authors examined profiles of body mass index (BMI) and patterns of weight gain associated with IIH. They also examined vision-specific health-related quality of life (HRQOL) in newly diagnosed IIH patients and explored the relative contribution of obesity and weight gain to overall HRQOL in this disorder. DESIGN: Matched case-control study. METHODS: Female patients with newly diagnosed IIH (n = 34) and other neuro-ophthalmologic disorders (n = 41) were enrolled in a case-control study to assess patterns of self-reported weight gain. The HRQOL was examined using the 25-Item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) and the SF-36 Health Survey (Physical Components Summary and Mental Components Summary [MCS]). RESULTS: Higher BMIs were associated with greater risk of IIH (P = .003, logistic regression analysis adjusting for case-control matching), as were higher percentages of weight gain during the year before symptom onset (P = .004). Moderate weight gain (5% to 15%) was associated with a greater risk of IIH among both obese and nonobese patients. Obesity and weight gain influenced the relation between HRQOL and IIH only for subscale scores reflecting mental health (SF-36 MCS). The NEI-VFQ-25 and SF-36 subscale scores were lower in IIH compared with other neuro-ophthalmologic disorders and published norms. CONCLUSIONS: Higher levels of weight gain and BMI are associated with greater risk of IIH. Even nonobese patients (BMI <30) are at greater risk for IIH in the setting of moderate weight gain. Vision-specific and overall HRQOL are affected to a greater extent in IIH than in other neuro-ophthalmologic disorders. 相似文献
186.
三叶因子与胃黏膜保护的研究进展 总被引:1,自引:0,他引:1
三叶因子家族是一群主要由胃肠道黏液细胞分泌的小分子多肽.其共同特征为均含一特殊的P结构域及三叶状结构.这种稳定的结构使三叶因子家族具有明显的抗蛋白酶水解、酸消化及耐热特性,因而能在消化道复杂的环境中保持生物活性.目前在哺乳动物体内发现的有pS2/TFF1、SP/TFF2和ITF/TFF3三种,它们具有黏膜保护与修复、肿瘤抑制、信号传导、调节细胞凋亡等功能.本文阐述了三叶因子家族发现的历史,并初步探讨了其作用.同时也对三叶因子受体这一热点的研究现状进行总结. 相似文献
187.
188.
脑复清胶囊中阿魏酸的含量测定研究 总被引:5,自引:0,他引:5
目的:建立薄层扫描法测定脑复清胶囊中阿魏酸含量的方法。方法:采用碱水提取,酸化后以醋酸乙酯萃取脑复清胶囊中阿魏酸,薄层法测定含量。结果:本方法线性方程为y=127997.95x 1090.60,r=0.9996(n=5),线性范围为0.50-2.53ug,同板精密度试验:RSD=4.40%(n=5)异板精密度试验。RSD=4.65%(n=5),平均加样回收率98.28%,结论:薄层扫描法可作为脑复清胶囊中阿魏酸的含量测定8方法,本实验研究为该产品的质量控制提供了可靠依据。 相似文献
189.
目的:通过使用CT三维测量髋臼发育情况及髋臼对股骨头覆盖率对比性观察,整体反映髋臼发育情况。方法:①观察对象:选择2003-06/2005-04对41例发育性髋关节脱位患者55个髋关节。其中男12例,女29例;年龄18个月~6岁。患髋右侧23例,左侧32例,其中双侧12例。健康侧27髋。患儿家属均知情同意。②实验方法:所有患儿使用PQ6000型多层螺旋CT扫描,扫描数据进行骨组织三维重建。将测量数据制成图表,显示三维的髋臼发育情况,并量化表示髋臼的缺损情况。③实验评估:计算不同截面正常侧髋臼指数、中心边缘角(假设符合正态分布)的均数、标准差、分布范围及95%可信区间。观察发育性髋关节脱位术前术后骨骼形态学变化。分别在术前、术后测量患者患侧髋臼指数、中心边缘角和前倾角,测量值均分别与正常值进行对比。结果:患侧55个髋,健康侧27髋,均进入结果分析。①发育性髋关节脱位术前术后骨骼形态学变化:术前55侧发育性髋关节脱位髋关节脱位程度为,参照T"nnis分类方法,Ⅰ度5髋(9.1%),Ⅱ度11髋(20%),Ⅲ度32髋(58.2%),Ⅳ度7髋(12.7%)。术后患者均表现髋臼α角均>90°,头臼呈同心圆对位,Shenton线连续,股骨头较术前明显发育,原先未出现头骺的患者,出现头骺,但较正常仍偏小;髋臼口呈类圆形,髋臼边缘欠光滑,髋臼整体呈一定程度前倾。②术前术后髋臼指数、中心边缘角和前倾角变化对比:术后患者的髋臼指数和前倾角与正常对照组之间差异无显著性(P>0.05),术后患者的中心边缘角大于正常对照组[(33.4±2.6)°(29.1±2.0)°,P<0.01],术后患者的髋臼指数和前倾角测量值均小于术前(P<0.01)。结论:介绍了一种对髋臼形态测量的新方法,它能够全面反映髋臼的发育情况,不但增加了对中心边缘髋臼病理改变的认识程度,还为手术提供了精确的可信度较高的矫形设计方案。 相似文献
190.
Diffusion-Weighted Magnetic Resonance Imaging as a Cancer Biomarker: Consensus and Recommendations 总被引:3,自引:0,他引:3 下载免费PDF全文
Anwar R Padhani Guoying Liu Dow Mu-Koh Thomas L Chenevert Harriet C Thoeny Taro Takahara Andrew Dzik-Jurasz Brian D Ross Marc Van Cauteren David Collins Dima A Hammoud Gordon JS Rustin Bachir Taouli Peter L Choyke 《Neoplasia (New York, N.Y.)》2009,11(2):102-125
On May 3, 2008, a National Cancer Institute (NCI)-sponsored open consensus conference was held in Toronto, Ontario, Canada, during the 2008 International Society for Magnetic Resonance in Medicine Meeting. Approximately 100 experts and stakeholders summarized the current understanding of diffusion-weighted magnetic resonance imaging (DW-MRI) and reached consensus on the use of DW-MRI as a cancer imaging biomarker. DW-MRI should be tested as an imaging biomarker in the context of well-defined clinical trials, by adding DW-MRI to existing NCI-sponsored trials, particularly those with tissue sampling or survival indicators. Where possible, DW-MRI measurements should be compared with histologic indices including cellularity and tissue response. There is a need for tissue equivalent diffusivity phantoms; meanwhile, simple fluid-filled phantoms should be used. Monoexponential assessments of apparent diffusion coefficient values should use two b values (> 100 and between 500 and 1000 mm2/sec depending on the application). Free breathing with multiple acquisitions is superior to complex gating techniques. Baseline patient reproducibility studies should be part of study designs. Both region of interest and histogram analysis of apparent diffusion coefficient measurements should be obtained. Standards for measurement, analysis, and display are needed. Annotated data from validation studies (along with outcome measures) should be made publicly available. Magnetic resonance imaging vendors should be engaged in this process. The NCI should establish a task force of experts (physicists, radiologists, and oncologists) to plan, organize technical aspects, and conduct pilot trials. The American College of Radiology Imaging Network infrastructure may be suitable for these purposes. There is an extraordinary opportunity for DW-MRI to evolve into a clinically valuable imaging tool, potentially important for drug development. 相似文献