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51.
Angiogenesis, the growth of new blood vessels, is believed to aid tumor progression and metastasis. Tumor progression is also influenced by the extent of proliferation and apoptosis. This study, therefore, analyzed in lesions of the oral cavity, the significance of angiogenesis in relation to apoptosis, expression of apoptosis regulatory p53, bax and bcl-2 proteins as well as tissue proliferation defined by cyclin D1 expression. Results from this study suggest that angiogenesis increases as histological abnormality increases in the oral mucosa. The expression of apoptosis regulatory proteins also appears to be altered in a histologically dependent manner. The correlation seen between CD34 expression, cyclin D1 and TUNEL reactive cells suggests that increased angiogenesis, decreased apoptosis and deregulated proliferation occur simultaneously during tumor progression in the oral mucosa. Presence of a mutant p53, increased bcl-2 expression and altered bax expression are also involved in this complex process.  相似文献   
52.
A dentinogenic ghost cell tumour in an 80-year-old male patient is presented. It is an extremely rare tumour and only 10 cases have been reported in the English literature. The lesion showed odontogenic epithelium, ghost cells, dentinoid, giant cells. The immunohistochemical analysis for Mib-1 and bcl-2 showed a strong positivity of the cells of the odontogenic epithelium, while with p53 only a rare positivity was observed. Completely negative were the ghost cells, giant cells and dentinoid material. In this tumour the cells expressing Mib-1 and bcl-2 could be the cells that proliferate, and that could undergo malignant transformation.  相似文献   
53.
In Sweden, snuff (locally known as snus), was introduced since the year 1637. Presently, Sweden has the highest per capita consumption and sale figures of snuff in the world, and the habit is becoming increasingly popular. Snus is manufactured into a dry form used in the nasal cavity and a moist form used in the oral cavity. Snus manufactured for oral use is a moist ground tobacco of Dark Kentucky or Virginia species mixed with an aqueous solution of water and other blending ingredients. This form of snuff is found in two types: (1) loose and (2) portion-bag-packed. These are the most widely used. The loose moist form (1–2 g a quid) is the most popular type consumed by 73% of the males, followed by the portion-bag-packed form (0.5–1 g a quid), consumed by 13% of the males, while 14% of the males are mixed users. The majority of snus users place the quid in the vestibular area of the upper lip, and the prevalence among persons 15 years of age or older is 15.9% among males and 0.2% among females. The pH of snus has declined from a previous range of 8–9 to a range of 7.8–8.5, moisture content ranges 35–60% and nicotine content is in the order of 5–11 mg/g dry wt tobacco-specific N-nitrosamines (TSNAs) in micrograms (N′-nitrosonornicotine: NNN 5–9; 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone: NNK 1–2; N′-nitrosoanatabine: NAT 2–5). In the Sudan, snuff, locally known as toombak, was introduced approximately 400 years ago. It is always processed into a loose moist form, and its use is widespread in the country. Tobacco used for manufacture of toombak is of the species Nicotiana rustica, and the fermented ground powder is mixed with an aqueous solution of sodium bicarbonate. The resultant product is moist, with a strong aroma, highly addictive and its use is widespread particularly among males. Its pH range is 8–11, moisture content ranges 6–60% and nicotine content is from 8 to 102 mg/g dry wt, and TSNAs contents in micrograms (NNN 420–1 550; NNK 620–7 870; NAT 20–290). Snus and toombak dippers develop a clinically and histologically characteristic lesion at the site of dipping. Probably due to control of the TSNAs in snus, this type of snuff is associated with a lower risk of cancer of the oral cavity (relative risk: RR 5–6-fold), whereas the risk for cancer of the oral cavity among toombak users was high (RR 7.3–73.0-fold). In conclusion, the two snuff products significantly differ in many aspects. Most notable differences are tobacco species, fermentation and ageing, nicotine and TSNAs content, pH, expression of the p53 tumour supressor gene, and keratin types 13, 14, and 19. It was, therefore, the object of the present study to highlight the oral health hazards of toombak, and to compare it with snus regarding the aforementioned differences.  相似文献   
54.
回顾了我国内地医疗服务市场对外开放的政策历程 ,并探讨了其发展趋势 :营利性和非营利性医疗机构公平竞争的局面将形成、非内地资金开办的大型非营利性医疗机构打响医疗市场争夺战、与国际接轨 ,最终形成以人为本、以市场为导向的医疗服务模式和理念  相似文献   
55.
BACKGROUND: Recently, there have been large outbreaks of hand, foot and mouth disease (HFMD) mainly caused by enterovirus 71 (EV71) associated with severe neurological diseases in the Western Pacific Region (WPR). To monitor the realtime trend of EV71 transmission throughout the WPR, the authors conducted a molecular epidemiological analysis of EV71 infection. METHODS: Viruses were isolated from clinical samples from patients with HFMD or those with neurological complications. The EV71 isolates were identified by microneutralization assay. The VP4 and/or VP1 regions of recent EV71 isolates were sequenced and subjected to phylogenetic analysis using reference EV71 strains. RESULTS: The phylogenetic analysis of EV71 isolates from the WPR revealed two major genogroups, B and C, based on the nucleotide sequence alignment of the VP1 or VP4 region. These two major genogroups were further divided into subgenogroups, B1, B2, B3, and B4 and C1, C2, C3 and C4, respectively. CONCLUSIONS: The molecular epidemiological analyses of recent and previous EV71 isolates in the WPR indicated that two major genogroups of EV71 are co-circulating in Australia, Malaysia, Singapore, Taiwan and Japan. Recent EV71 isolates in Mainland China constitute a new distinct genetic cluster, subgenogroup C4. Two major lineages of EV71 are the major causative agents of the present HFMD epidemics in the WPR and both are considered to be neurovirulent.  相似文献   
56.
57.
对我国医疗卫生服务信息公开的建议   总被引:1,自引:1,他引:1  
政府卫生行政机构职能及医院服务意识的切实转变要求医疗卫生服务信息公开,各地的有益尝试及成功经验为卫生服务信息公开提供了可供参考的实践模式,而其存在的不足则引发了对我国医疗卫生服务信息公开的对策及建议.  相似文献   
58.
目的:探讨用Ilizarov技术缓慢牵伸原理来矫正膝关节屈曲挛缩畸形。方法:用借鉴Ilizarov技术缓慢牵伸原理研制的石膏撑开器,将分次石膏夹楔变成近似连续的缓慢撑开,来矫正膝关节重度屈曲挛缩畸形。结果:36例40个膝关节,伴有条索状挛缩或股骨下端骨性畸形者,需通过膝后软组织松解或股骨髁上截骨,膝关节伸直皆达到矫形需要的要求,未发生影响疗效的并发症。结论:借鉴Ilizarov技术缓慢牵伸原理研制的石膏撑开器,是实现了无痛、微创、简便、安全治疗膝关节屈曲挛缩的有效方法。  相似文献   
59.
目的在面瘫患者健侧部分面肌中注射A型肉毒毒素用以矫正口角歪斜和不对称的鼻唇沟,以满足美容的需要。方法将2001年1月 ̄2005年12月来在门诊和住院的部分面瘫患者作为观察对象,除对照组外治疗组分别在健侧面肌中注射A型肉毒毒素,依据注射剂量随机分为5个治疗组:A组(各肌注射1.25U)、B组(各肌注射2.50U)、C组(各肌注射5.00U)、D组(降、提口角肌和颧大、小肌各注射2.50U,笑肌注射5.00U)和E组(降、提口角肌和颧大、小肌各注射5.00U,笑肌注射2.50U),3d后定期观测每例患者双侧口角到门齿中缝的距离差。结果除A组外,各治疗组的口角歪斜和鼻唇沟不对称均得到不同程度的纠正,注射剂量越大起效越快,持续时间越长,但表情动作受到的影响也略大。结论根据口角歪斜和鼻唇沟不对称的程度,在健侧面肌注射相应剂量的A型肉毒毒素,既可以较好地纠正面瘫患者的口角歪斜和鼻唇沟的不对称,又可以避免并发症的发生。  相似文献   
60.
目的: 探讨血管内皮生长因子(VEGF)和血管内皮生长因子-C(VEGF-C)在口腔鳞癌中的表达及相关性.方法: 采用免疫组织化学染色和图像分析仪检测VEGF和VEGF-C的染色强度,计算免疫组化阳性指数(positive index,PI).结果: 在口腔鳞癌中淋巴结转移组VEGF和VEGF-C的表达均较无转移组增高(P<0.05),VEGF和VEGF-C的表达之间存在正相关关系(P<0.05,r=0.344).结论: 在口腔鳞癌中VEGF和VEGF-C可能存在复杂的相互促进表达、协同作用.  相似文献   
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