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71.
应用自动化图象分析仪对131个胃粘膜肠型病灶(单纯性肠化27个;异型增生:轻度30,中度35个,重度20个;肠型胃癌19个)进行定量分析。以单个腺管内细胞核总面积与细胞面积之比(ING)作为反映细胞核大小、数量及覆层排列程度的客观定量指标。结果发现:单纯性肠化(对照组)0.165±0.025,轻度异型增生0.21±0.023,中度异型增生0.259±0.026,重度异型增生0.32±0.028,分化型胃癌0.371±0.052,各组ING值呈正态,各组间的均值有非常显著的差异(P<0001)。因而,ING可作为胃粘膜癌前病变诊断的指标。 相似文献
72.
Mana Ichimura Koichi Hiratsuka Naomi Ogura Tadahiko Utsunomiya Hiroyuki Sakamaki Toshirou Kondoh Yoshimitsu Abiko Shigeo Otake Masafumi Yamamoto 《Journal of oral pathology & medicine》2006,35(3):167-174
BACKGROUND: To understand the immunopathological features of oral lichen planus (OLP), we analyzed the expression of chemokines in the epithelial cell layers. Methods: Epithelia from OLP or healthy gingiva were collected by laser microdissection. The chemokine and chemokine receptor expressions in the epithelia were analyzed by DNA microarray. RESULTS: High levels of MIP-3alpha/LARC/CCL20 and its receptor CCR6 were expressed in the lesional epithelia. Furthermore, DC-CK1/CCL18, ELC/CCL19, SDF-1/CXCL12 and CXCR4 expressions were also increased. Immunohistologial analysis showed that high numbers of Langerhans cells (LCs) were present in the epithelia of OLP. Lesional epithelia also expressed high levels of the ligands specific for CXCR3 (e.g. MIG/CXCL9, IP-10/CXCL10 and I-TAC/CXCL11) and CCR5 (e.g. RANTES/CCL5). CONCLUSIONS: Infiltration of LCs is orchestrated by CCR6. Further, LCs residing in the lesional epithelia may be a mature phenotype. Moreover, infiltration of T cells in OLP could be mediated by signaling pathways through CXCR3 and CCR5. 相似文献
73.
Hiroko Utsunomiya Wanninayake M. Tilakaratne Kazufumi Oshiro Satoshi Maruyama Makoto Suzuki Hiroko Ida-Yonemochi Jun Cheng Takashi Saku 《Journal of oral pathology & medicine》2005,34(8):498-507
BACKGROUND: Oral submucous fibrosis (OSF) is a chewing habit-related pre-cancerous condition of the oral mucosa affecting predominantly south Asians. It is histopathologically characterized by epithelial atrophy and fibrosis of the subepithelial connective tissue. Fibrosis extends all the way into the muscle layer, leading to difficulty in mouth opening. However, the dynamics of extracellular matrix (ECM) remodeling with OSF progression is largely unknown. METHODS: Forty biopsy specimens of OSF and 10 of normal buccal mucosa were examined for expression/deposition modes of eight ECM molecules by histochemistry, immunohistochemistry, and in situ hybridization. RESULTS: In the early stage of OSF, tenascin, perlecan, fibronectin, collagen type III were characteristically enhanced in the lamina propria and the submucosal layer. In the intermediate stage, the ECM molecules mentioned above and elastin were extensively and irregularly deposited around muscle fibers. In the advanced stage, such ECM depositions decreased and were entirely replaced with collagen type I only. Their gene expression levels varied with progression of fibrosis, but the mRNA signals were confirmed in fibroblasts in the submucosal fibrotic areas. CONCLUSIONS: The results indicate that the ECM remodeling steps in OSF are similar to each phase of usual granulation tissue formation. Restricted mouth opening may be a result of loss of variety of ECM molecules including elastin into the homogeneity of collagen type I replacing muscle fibers. 相似文献
74.
Objective: This pilot study was intended to test whether a training protocol improved validity of odor judges (OJs), with or without experience, and whether odorant types differed in error proneness.
Methods: The OJs (four experienced, two inexperienced) completed a 4-phase training protocol based on the American Society of Testing and Materials standards (ASTM): (i) introduction to sensory scales, n-butanol reference, sniffing techniques; (ii) pretraining measurements; 20 samples of varying intensities of four unpleasant and three pleasant odorants; (iii) exercises assessing quality, intensity, ranking, and matching; and (iv) post-training measurements.
Main outcome measures: Subjects' intensity scores were analyzed as the absolute difference from the 'true' intensity (ASTM n-butanol standard) using repeated measures ANOVA.
Results: Training significantly ( P = 0.02) reduced OJ errors. Experienced and novice judges did not differ in average errors ( P = 0.99), or in improvement in error from pre- to post-training ( P = 0.94). Improvement was consistent from pre- to post-training for all odorants except dimethylsulfide for which errors worsened ( P = 0.01). Unpleasant and pleasant odorants differed ( P = 0.006) in error. After removing water the effects of water control scores from the pleasant odorants, the difference was not significant ( P = 0.26).
Conclusions: The OJs improved in their ability to assess odor intensity irrespective of previous experience. Training is recommended for all OJs prior to research trials. 相似文献
Methods: The OJs (four experienced, two inexperienced) completed a 4-phase training protocol based on the American Society of Testing and Materials standards (ASTM): (i) introduction to sensory scales, n-butanol reference, sniffing techniques; (ii) pretraining measurements; 20 samples of varying intensities of four unpleasant and three pleasant odorants; (iii) exercises assessing quality, intensity, ranking, and matching; and (iv) post-training measurements.
Main outcome measures: Subjects' intensity scores were analyzed as the absolute difference from the 'true' intensity (ASTM n-butanol standard) using repeated measures ANOVA.
Results: Training significantly ( P = 0.02) reduced OJ errors. Experienced and novice judges did not differ in average errors ( P = 0.99), or in improvement in error from pre- to post-training ( P = 0.94). Improvement was consistent from pre- to post-training for all odorants except dimethylsulfide for which errors worsened ( P = 0.01). Unpleasant and pleasant odorants differed ( P = 0.006) in error. After removing water the effects of water control scores from the pleasant odorants, the difference was not significant ( P = 0.26).
Conclusions: The OJs improved in their ability to assess odor intensity irrespective of previous experience. Training is recommended for all OJs prior to research trials. 相似文献
75.
76.
Jessica Swoboda DDS H. Asuman Kiyak MA PhD Rigmor E. Persson DDS MSD G. Rutger Persson DDS PhD David K. Yamaguchi PhD Michael I. MacEntee LDS FRCD© PhD Christopher C.L. Wyatt BSc DMD MSc 《Special care in dentistry》2006,26(4):137-144
There is limited information regarding oral health status and other predictors of oral health‐related quality of life. An association between oral health status and perceived oral health‐related quality of life (OHQOL) might help clinicians motivate patients to prevent oral diseases and improve the outcome of some dental public health programs. This study evaluated the relationship between older persons' OHQOL and their functional dentition, caries, periodontal status, chronic diseases, and some demographic characteristics. A group of 733 low‐income elders (mean age 72.7 ISD=4.71, 55.6% women, 55.1% members of ethnic minority groups in the U.S. and Canada) enrolled in the TEETH clinical trial were interviewed and examined as part of their fifth annual visit for the trial. OHQOL was measured by the Geriatric Oral Health Assessment Index (GOHAI); oral health and occlusal status by clinical exams and the Eichner Index; and demographics via interviews. Elders who completed the four‐year assessment had an average of 21.5 teeth (SD=6.9). with 8.5 occluding pairs (SD=4.6), and 32% with occlusal contacts in all four occluding zones. Stepwise multiple regressions were conducted to predict total GOHAI and its subscores (Physical, Social, and Worry). Functional dentition was a less significant predictor than ethnicity and being foreign‐bom. These variables, together with gender, years since immigrating, number of carious roots, and periodontal status, could predict 32% of the variance in total GOHAI, 24% in Physical, 27% in Social, and 21 % in the Worry subscales. These findings suggest that functional dentition and caries influence older adults' OHQOL, but that ethnicity and immigrant status play a larger role. 相似文献
77.
78.
The calculation of the extent of the ring scotoma around positive lenses, as conventionally taught to students of clinical optics, indicates that the scotoma is of a significant size. Using knife-edge lenses this study shows that the calculations are invalid due to the finite size of the eye's entrance pupil and in many instances the scotoma is shown not to exist. The effect noticed in clinical practice is probably largely due to the frame and the edging techniques used which add to the refractive scotoma which is present with high powered lenses, large apertures and/or small pupil sizes. 相似文献
79.
80.
Chretien Marie Francoise; Lebouvier Brigitte; Denis Alain; Chappard Daniel 《Human reproduction (Oxford, England)》1998,13(10):2767-2771
A cytomorphometric analysis of superficial vaginal cells inwomen in three groups of different types of hormonal concentrationwas made. There were 15 women in each group. Group I was studiedduring a natural cycle, group II under oral contraceptive therapyand group III during an in-vitro fertilization (IVF) stimulationprotocol. Morphometric parameters were measured on an imageanalyser. The area, perimeter and several form factors weremeasured separately for nuclei and cytoplasm. The nucleus:cytoplasmicratio was also determined. The cytoplasmic area was significantlyreduced in group II and was associated with a statisticallysignificant reduction of the nuclear area. The nucleus:cytoplasmicratio appeared significantly increased in group II and reducedin group III. Low oestradiol impregnation obtained with an oralminidosed contraceptive interfered with vaginal cell maturation.High oestradiol concentrations obtained during IVF protocolsinduced marked nuclear pycnosis but did not induce supra-physiologicalcell enlargement. Maximal cell size is genetically regulatedaccording to Driesch's law of volume invariance and hormonalover-stimulation has no effect on cell size. The nucleus:cytoplasmicratio appears to be a powerful parameter reflecting the oppositeeffects of hormones on cell compartments. 相似文献