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101.
Jean Marie Jully Marie Christine Béné Gérard Martin Gilbert Faure 《Journal of clinical periodontology》1986,13(3):223-227
The cellular infiltrate present in human diseased gingiva was analyzed in biopsies from 12 patients with gingivitis or periodontitis. The samples studied had been obtained in the course of surgery at inflammatory sites remaining after institution of periodontal treatment. Histological and immunological techniques were used to identify macrophages, B-cells, plasma-cells, T-cells and T cell subsets, as well as cells expressing class II HLA membrane antigens. T-cells appeared as the predominant population, but plasma-cells were also visualized in nearly all samples. Both OKT4+ and OKT8+ cells were seen in all cases, the latter being more numerous in periodontitis patients. Interdigitating-like cells were observed, positively labelled for class II antigens, as well as macrophages which were more numerous in periodontitis patients. These results suggest the participation of all components of the immune response in gingival disease, in a way resembling chronic recurrent inflammatory diseases. 相似文献
102.
X Dong M He X Song B Lu Y Yang S Zhang N Zhao L Zhou Y Li X Zhu R Hu 《Diabetic medicine》2007,24(12):1482-1486
AIMS: Our aim was to assess performances of the Cockcroft-Gault and simplified Modification of Diet in Renal Disease (MDRD) formulae in estimating glomerular filtration rate (GFR) in Chinese diabetic populations and their association with vascular risks. METHODS: A total of 1009 patients with Type 2 diabetes were categorized into low estimated GFR groups (GFR < 60 ml/min/1.73 m(2)) and control groups by the two equations. The performances of these formulae were assessed at different stages of kidney function. Carotid artery intima-media thickness (IMT) and the prevalence of diabetic retinopathy or albuminuria were compared among the groups. The ability of these formulae to identify established vascular risk markers using sensitivity, specificity, positive and negative predictive values were also compared. RESULTS: The prevalence of low estimated GFR was 32.7% with the Cockcroft-Gault formula and 5.2% with the MDRD formula, respectively. In low estimated GFR subjects by the MDRD formula, IMT was significantly thicker than those by the Cockcroft-Gault formula (1.2 mm vs. 1.0 mm; P < 0.05), with a higher prevalence of albuminuria (78.4 vs. 52.8%, P < 0.05) and diabetic retinopathy (46.5 vs. 30.5%; P < 0.05). The Cockcroft-Gault formula gave a specificity of 71.7% and a sensitivity of 37.0%, and the MDRD formula gave a specificity of 96.6% and a sensitivity of 7.9% in estimating low GFR relevant for established vascular risks. CONCLUSIONS: These formulae performed differently in Chinese diabetic populations. The simplified MDRD formula is minimally superior to the Cockcroft-Gault formula for its high specificity and positive predictive values in estimating low GFR relevant for vascular risks. 相似文献
103.
目的 初步建立阴道粘膜上皮细胞体外培养方法,为阴道粘膜上皮研究提供实验模型.方法 取雌性新西兰大白兔阴道粘膜组织小块,胶原酶Ⅳ和胰蛋白酶联合消化分离法收集上皮细胞,接种于角朊细胞无血清培养液中静置培养、传代.动态观察细胞生长增殖情况,扫描和透射电镜观察超微结构,流式细胞仪测定细胞增殖周期,并进行免疫组织化学鉴定.结果 体外培养的阴道粘膜上皮细胞为二倍体细胞,增殖状态良好,细胞间可见桥粒连接,免疫组化角蛋白染色阳性.细胞的超微结构和免疫组化染色均具有上皮细胞特征.结论 在本实验条件下,体外培养的阴道粘膜上皮细胞具有较好的增殖能力,可作为阴道粘膜上皮研究的理想实验模型. 相似文献
104.
In vivo Intracellular Recording of Neurons in the Supraoptic Nucleus of the Rat Hypothalamus 总被引:3,自引:0,他引:3
R. E. J. Dyball J-G. Tasker J-P. Wuarin F. E. Dudek 《Journal of neuroendocrinology》1991,3(4):383-386
Intracellular recordings were made from cells in the hypothalamic supraoptic nucleus in the urethane-anaesthetized male rat using the ventral surgical approach. Impalements lasted from 5 min to 1 h and recorded cells had an input resistance of 55 to 170 megohms. Spikes of over 50 mV were recorded from 14 cells which could be antidromically activated by stimulation of the neural stalk. The spikes showed a hyperpolarizing afterpotential and the broadening characteristic of rapidly firing magnocellular neurons, which recovered rapidly (<200 ms). When depolarized, the cells showed evidence of a transient potassium current. Recurrent synaptic coupling between the recorded cell and adjacent cells would be expected to alter the hyperpolarizing afterpotential of an antidromic spike as compared with a spontaneous spike; no perceptible difference in the waveforms of the different types of spike could be detected in 11 spontaneously active cells. Application of just subthreshold stimuli to the neural stalk did not evoke depolarizing or hyperpolarizing potentials. Suprathreshold shocks to the neural stalk, when the antidromic spike was prevented by collision, also had no discernible effect on membrane potential. Thus intracellular recordings from magnocellular neurons in vivo revealed electrophysiological properties similar to those seen in vitro. No evidence for synaptic interconnection between magnocellular neurons was found in male rats. 相似文献
105.
免疫组化法检测非甲-非庚型肝炎患者肝组织中输血传播病毒 总被引:1,自引:1,他引:0
目的 检测非甲-非庚型肝炎患者肝组织输血传播病毒(TTV)感染状况,TTV感染与肝组织炎症程度 及与血液学指标的相关性。方法 应用免疫组织化学法检测52例非甲-非庚型肝炎患者肝组织中TTV,并经原位 杂交证实;对TTV阳性和阴性组的血液学生化指标,诸如血清丙氨酸转氨酶(ALT)、血清天冬氨酸转氨酶(AST)、血 清总胆红素(TBIL)、白蛋白(ALB)、γ 球蛋白(γ G)、凝血酶原活动度(PTA)及组织学活动指数(HAI)进行了比较。 结果 非甲-非庚型肝炎患者肝组织中TTV抗原(TTVAg)阳性15例,检出率为28.8%;阳性物质主要定位于肝细 胞浆内,呈棕黄色细小颗粒,偶见肝细胞核内有表达;TTV阳性表达细胞呈单个、散在或片簇状分布;TTVAg阳性的 组织切片经苏木素-伊红(HE)染色后,可观察到病毒性肝炎的一些病理变化,如肝细胞胞浆疏松化、气球样变、嗜酸 样变、灶性坏死、凋亡、小叶内及汇管区炎细胞浸润;从15例TTVAg阳性病例中任选10例进行TTV DNA原位杂交 检测,结果8例阳性,二者符合率80.0%;同时对5例免疫组化TTVAg阴性肝组织进行TTV DNA原位杂交检测,结 果5例均为阴性,二者符合率100%;TTVAg阳性组ALT、AST、TBIL、γ G均值均高于TTVAg阴性组,ALB、PTA 均值均低于TTVAg阴性组,但两组比较差异无统计学意义(P>0.0 相似文献
106.
本文介绍使用氨气敏电极,采用标准曲线法简便、快速、准确测定血氨的方法。取空腹血1ml,用1M HClO_4沉淀蛋白,以0.1M NH_4Cl—0.6MNa_2SO_4作内充液,碱化后的上清液可在2~3min内测试完毕。40例正常成人血氨的测定结果:■=31.4μmol/L N;S=6.4μmol/L N;■±2S(正常值范围)为18.6~44.2μmol/L N。10份血样的平均回收率为100.4%。该法用血少、简便、快速;结果较稳定、准确,适用于临床检验。 相似文献
107.
108.
E. Drakaki E. Borisova M. Makropoulou L. Avramov A. A. Serafetinides I. Angelov 《Skin research and technology》2007,13(4):350-359
BACKGROUND/PURPOSE: Laser-induced autofluorescence spectroscopy provides excellent possibilities for medical diagnostics of different tissue pathologies including cancer. However, to create the whole picture of pathological changes, investigators collect spectral information from patients in vivo or they study different tumor models to obtain objective information for fluorescent properties of every kind of healthy and diseased tissue. Therefore, it is very important to find the most appropriate, and close to the human skin, animal samples from the fluorescence point of view, which will allow the extrapolation of the animal data to human spectroscopic diagnostics. METHODS: In the present work, we examined the autofluorescence properties of different animal skin tissues, which are considered as the most common skin models. A nitrogen laser was used as an excitation source. Samples of healthy mouse, chicken and pig skin in vivo and/or ex vivo were studied and were compared with results obtained from investigations of healthy human skin in vivo. RESULTS AND CONCLUSION: Specific features of the recorded spectra are discussed and the possible origin of the obtained fluorescence signals is proposed. Quantitative evaluation of data extrapolation for each skin type is also depicted. 相似文献
109.
目的了解鼻窦炎患儿家长对儿童鼻窦炎相关知识的认知情况,为进一步加强卫生宣教、预防儿童鼻窦炎提供理论依据。方法对65名鼻窦炎患儿家长进行关于儿童鼻窦炎发病因素、临床表现、并发症以及对儿童生长发育影响等问题的问卷调查。结果调查显示95.4%的家长对儿童鼻窦炎知识缺乏了解,且知识获得途径单一。结论应通过各种途径加强儿童鼻窦炎知识的宣教,积极预防儿童鼻窦炎。 相似文献
110.
Teng-Yi Huang Hsiao-Wen Chung Fu-Nien Wang Cheng-Wen Ko Cheng-Yu Chen 《Magnetic resonance in medicine》2004,51(2):243-247
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished. 相似文献