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91.
喉鳞状细胞癌中PTEN蛋白表达与微血管密度的相关性 总被引:1,自引:1,他引:1
目的 研究喉鳞癌(LSCC)组织中抑癌基因PTEN蛋白(PTEN)的表达与肿瘤微血管密度(MVD)之间的相关性。方法 采用免疫组化SP法检测10例正常喉组织、20例癌旁组织和60例LSCC组织中PTEN基因和MVD的表达情况。结果 PTEN在LSCC、癌旁喉组织及正常组织中阳性表达率分别为70.00%、95.00%、100.00%,差异有显著性(P〈0.01)。LSCC组织中PTEN蛋白表达在TNM分期Ⅰ~Ⅱ期、高中分化癌、无转移、生存率〉3年的患者中表达水平较Ⅲ~Ⅳ期、低分化和有转移、生存率〈3年的患者高,差异有显著性(P〈0.05)。在不同恶性程度、分化程度、预后及有无转移的LSCC组织中,PTEN蛋白表达与MVD呈显著负相关(P〈0.05)。结论 PTEN基因突变和/或缺失可能在LSCC的发生、发展和血管形成中发挥重要作用。PTEN、MVD是反映LSCC生物学行为的重要指标。 相似文献
92.
Prevalence of Candida spp., xerostomia,and hyposalivation in oral lichen planus – A controlled study
Objective
To determine the frequency of Candida spp., xerostomia, and salivary flow rate (SFR) in three different groups: patients with OLP (OLP group), patients with oral mucosal lesions other than OLP (non‐OLP group), and subjects without oral mucosal lesions (control group).Material and methods
Xerostomia as well as SFR was investigated in the three groups. Samples for isolation of Candida spp. were collected from OLP lesions (38 patients), non‐OLP lesions (28 patients), and healthy subjects (32 subjects).Results
There was no statistically significant difference regarding the frequency of xerostomia and hyposalivation among the three groups (P > 0.05). A higher prevalence for colonization by Candida spp. was found in the healthy subject as compared to that of patients with OLP (P = 0.03) and non‐OLP (P = 0.02) groups. Low SFR was not a factor for colonization by Candida spp.Conclusions
Xerostomia and hyposalivation occur with similar frequency in subjects with and without oral lesions; also, the presence of oral lesions does not increase the susceptibility to colonization by Candida spp. It seems that any study implicating Candida spp. in the malignant transformation of oral lesions should be carried out mostly on a biochemical basis, that is, by testing the capability of Candida spp. to produce carcinogenic enzyme. 相似文献93.
CRISTIANE MARIA DA COSTA‐SILVA FABIANO JEREMIAS JULIANA FELTRIN De SOUZA RITA De CÁSSIA LOIOLA CORDEIRO LOURDES SANTOS‐PINTO ANGELA CRISTINA CILENSE ZUANON 《International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children》2010,20(6):426-434
International Journal of Paediatric Dentistry 2010; 20: 426–434 Background. The prevalence of molar incisor hypomineralization (MIH) varies considerably around the world; however, few studies have examined MIH in South American countries. Objective. To evaluate the prevalence, severity, and clinical consequences of MIH in Brazilian children residing in rural and urban areas of the municipality of Botelhos, Minas Gerais, Brazil. Methods. Children aged 6 to 12 years (n = 918) with all four‐first permanent molars erupted had these teeth evaluated according to the European Academy of Paediatric Dentistry (EAPD) criteria. The examinations were conducted by two previously trained examiners, and the dental impact caused by MIH was evaluated with the Decayed, Missing and Filled Teeth (DMFT) index (WHO). Results. Molar incisor hypomineralization was present in 19.8% of the 918 children, with a higher prevalence in rural areas. The majority of the defects presented were demarcated opacities without post‐eruptive structural loss, which has been considered as mild defects. Children with MIH had higher DMFT values. Conclusion. Despite the high prevalence of MIH, the severity of the defects was mild. The results indicate a positive association between MIH and the presence of dental caries. 相似文献
94.
Knowledge,attitude and practice among Health Visitors in the United Kingdom toward children's oral health 下载免费PDF全文
95.
96.
高海拔地区急性呼吸窘迫综合征和多器官功能障碍综合征诊断标准的研究--附高海拔地区急性呼吸窘迫综合征诊断标准重修意见稿 总被引:11,自引:5,他引:11
目的:判别高海拔地区急性呼吸窘迫综合征(H-ARDS)和多脏器功能障碍综合征(H-MODS)诊断指标参数和平原的差异,重估原H-ARDS诊断标准(1999年兰州会议)的实用性和可操作性。方法:将资料齐全且符合庐山、Marshall ARDS/MODS诊断标准的360例患者,根据所在海拔高度分为平原对照组(CG,n=93),≥1517m高度组(H1G,n=223),2261-2400m高度组(H2G,n=44)。3组均按庐山、Marshall和自拟ARDS/MODS的标准(简称兰州标准)建成3个标准数据模型,绘制ROC曲线。根据曲线下面积、最佳截断点对比3个标准在不同海拔梯度上预测ARDS/MODS结局的准确性。结果:用庐山标准验证CG组ROC下面积、敏感度、特异度优于Marshall标准,两者相比ROC下面积、敏感度、特异度依次为0.823、0.833、0.731比0.815、0.767、0.763;但用于验证高海拔区如H2G则庐山标准明显低于兰州标准,两标准的ROC下面积、敏感度、特异度依次为0.855、0.583、0.969比0.914、1.000、0.657;氧合指数(PaO2/FiO2)的最佳界值在CG、H1G和H2G依次为198.32mmHg、131.50mmHg、97.58mmHg;3组ARDS/MODS按平原标准评分分级,CG比较均匀分布在1-3级,而H1G和H2G的病例多集中在3级,多构成比χ^2检验,P<0.000。结论:(1)高海拔地区ARDS诊断标准与平原地区有明显差异,海拔高度≥1517m的兰州地区可能在区分平原与高原ARDS诊断标准是上一个有意义的分界线。已建立的H-ARDS诊断标准参数符合本地区实际,基本可行,参数范围仍宽,建议适度修改。MODS各项指标虽与平原有不同的变化趋向,但样本量较少,标准有待进一步完善。 相似文献
97.
M Okano DA Harn Jr M Abe MM Wang AR Satoskar K Nishizaki Y Masuda M Okano T Yoshino 《Allergy》1999,54(6):593-601
BACKGROUND: To date, no murine models have been reported to show the induction of both antigen-specific IgE and nasal eosinophilia, two of the major hallmarks of allergic rhinitis, after local sensitization in the absence of adjuvants, a phenomenon which reflects natural exposure. In this report, we attempted to establish a murine model representing an initiation of allergic rhinitis. METHODS: BALB/c, CBA/J, and C57BL/6 mice were sensitized intranasally to Schistosoma mansoni egg antigen (SEA) solely. After repeated sensitization, serum Ab titers, nasal eosinophilia, and cytokine production by nasal lymphocytes were determined. RESULTS: BALB/c mice produced SEA-specific IgE after repeated sensitization. High-dose sensitization to SEA induced IgE production in CBA/J mice, while C57BL/6 mice did not show the production throughout the period observed, suggesting that IgE production was regulated genetically. BALB/c mice also exhibited nasal eosinophilia after the nasal challenge. In addition, nasal lymphocytes sensitized with SEA intranasally produced significant amount of IL-5 in vitro. CONCLUSIONS: These results suggest that intranasal sensitization with SEA in the absence of adjuvants induces a Th2 immune reaction, reflecting the hallmarks of the initiation of allergic rhinitis both in vivo and in vitro, which is genetically regulated. 相似文献
98.
99.
原发性肉碱缺乏致脂质沉积性肌病的临床与病理特点 总被引:1,自引:0,他引:1
目的 分析原发性肉碱缺乏致脂质沉积性肌病(LSM)的临床与病理特点。方法 回顾性分析4例可能LSM患者的临床资料。结果 本组患者为亚急性或慢性起病,主要表现为近端肌无力,疲劳不能耐受;血清肌酶有不同程度的升高;肌电图示肌源性损害;病理检查示肌纤维内可见大量细小空泡和裂隙形成;MGT染色无破碎红纤维,油红O染色显示空泡为大量脂滴充填;受累纤维以Ⅰ型纤维为主。电镜证实肌纤维内脂滴堆积,可伴有线粒体的轻度增多。改善能量和糖皮质激素治疗有效。结论原发性肉碱缺乏致LSM是一种以易疲劳和肌无力为主要临床表现的脂质代谢障碍性肌病,病理改变以肌纤维内脂滴堆积为主,一般不伴有线粒体结构的明显异常。糖皮质激素治疗可获得良好疗效。 相似文献
100.
Erika E Forbes Douglas E Williamson Neal D Ryan Boris Birmaher David A Axelson Ronald E Dahl 《Neuropsychopharmacology》2006,59(1):24-30
BACKGROUND: Changes in the hypothalamic-pituitary-adrenal (HPA) axis, as evidenced by patterns of cortisol secretion, have been of interest in understanding depression and anxiety disorders across the life span. Previous studies of pediatric depression have pointed to the period around sleep onset as a key time point for observing alterations in cortisol secretion associated with affective disorders. Evidence also indicates that pubertal development may influence the expression of HPA dysregulation. We hypothesized that adolescents with depression and youth with anxiety disorders exhibit elevated peri-sleep-onset cortisol. METHODS: Plasma cortisol was sampled every 20 min around sleep onset from children and adolescents with major depressive disorder (n = 116), anxiety disorders (n = 32), or no history of psychiatric disorder (control; n = 76). Sleep onset was determined by polysomnography. Classification of participants as children or adolescents was based on Tanner staging of pubertal maturation. RESULTS: Children with anxiety disorders had higher peri-sleep-onset cortisol than children with depression or control children. Adolescents with depression had marginally higher peri-sleep-onset cortisol than control adolescents and significantly higher peri-sleep-onset cortisol than children with depression. CONCLUSIONS: Depression and anxiety are associated with altered cortisol secretion around sleep onset, and these changes appear to be influenced by pubertal maturation. 相似文献