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41.
Luca Oscar Redaelli De Zinis Andrea Bolzoni Cesare Piazza Piero Nicolai 《European archives of oto-rhino-laryngology》2006,263(12):1131-1135
Lymph node (LN) metastases represent the most important negative prognostic factor in squamous cell carcinoma (SCC) of the oral cavity, even though controversies still exist regarding their management. The aim of this study was to retrospectively analyze our experience in surgical management of SCC of the oral cavity with particular focus on the prevalence and localization of lymph nodal metastases and recurrences. The clinical records of 89 consecutive patients treated from 1983 to 2002 by concomitant surgery on both the T and N sites, excluding those undergoing salvage surgery, were reviewed. A total of 119 neck dissections (ND) were performed. Survival outcomes were calculated by the Kaplan–Meier method, while univariate comparisons by the log-rank and non-parametric tests were performed between different groups of patients. Five-year overall and determinate survivals were 50 and 57%, respectively. LN metastases were observed in 52% (56% of these showing extracapsular spread) and their presence strongly correlated with determinate survival (p < 0.0001). The prevalence of clinical and occult nodal disease was not related to the pT status. Neck levels II (59%) and I (56%) were most frequently involved. Metastases to level IV accounted for 15% of positive LN, even though 28% of them turned out to be skip metastases. Five neck recurrences were observed, only one of which was salvaged by surgery. The high prevalence of clinical and occult LN metastases in this setting suggests that ND should be performed on a nearly routine basis, even for lesions with a low-T category and a cN0 neck. Moreover, ND should always encompass level IV due to the possibility of skip metastases, particularly in tumors involving the oral tongue. In patients with a cN+ neck, levels from I to V should be addressed, particularly in the presence of metastases at levels III and IV. 相似文献
42.
S. Nour A. El-Sharkawy W. C. Burnett E. P. Horwitz 《Applied radiation and isotopes》2004,61(6):1173-1178
The objective of this work was to establish a new procedure for 228Ra determination of natural waters via preconcentration of radium on MnO2 and separation of its daughter, 228Ac, using Diphonix ion exchange resin. Following removal of potential interferences via passage through an initial Diphonix Resin column, the first daughter of 228Ra, 228Ac, is isolated by chromatographic separation via a second Diphonix column. A holding time of >30 h for 228Ac ingrowth in between the two column separations ensures secular equilibrium. Barium-133 is used as a yield tracer. Actinium-228 is eluted from the second Diphonix Resin with 5 ml 1 M 1-Hydroxyethane-1,1-diphosphonic acid (HEDPA) and quantified by addition of scintillation cocktail and LSC counting. Radium (and 133Ba) from the load and rinse solutions from the 2nd Diphonix column may be prepared for alpha spectrometry (for determination of 223Ra, 224Ra, and 226Ra) by BaSO4 microprecipitation and filtration. Decontamination tests indicate that U, Th, and Ra series nuclides do not interfere with these measurements, although high contents of 90Sr (90Y) require additional treatment for accurate measurement of 228Ra. Addition of stable Sr as a “hold back” carrier during the initial MnO2 preconcentration step was shown to remove most 90Sr interference. 相似文献
43.
葡萄糖筛选试验在妊娠期糖尿病诊断及治疗中的价值 总被引:5,自引:1,他引:4
目的 探讨 5 0 g葡萄糖筛选试验 (GCT)在妊娠期糖尿病 (GDM )诊断及治疗中的价值。 方法 选择 2 0 0 0年 1月~ 2 0 0 3年 6月在我院行产前检查并分娩的 5 0 gGCT异常的孕妇 36 8例 ,按血糖值分为 5组 :≥7.8~ <8.0mmol/L为Ⅰ组 ,≥ 8.0~ <9.0mmol/L为Ⅱ组 ,≥ 9.0~ <10 .0mmol/L为Ⅲ组 ,≥ 10 .0~ <11.0mmol/L为Ⅳ组 ,≥ 11.0mmol/L为Ⅴ组。比较 5组 75 g口服葡萄糖耐量试验 (OGTT)异常的比例及需用胰岛素治疗的病例数的差异。结果 5组GDM的发生率分别为 6 .9%、8.5 %、2 1.3%、4 7.8%和 85 .0 % ,75 gOGTT异常的发生率分别为 19.0 %、2 4 .2 %、5 1.1%、87.0 %和 90 .0 % ,且用胰岛素治疗的病例数随 5 0 gGCT血糖值的上升而增加。结论 5 0 gGCT在GDM的诊断及治疗方案的预测方面均有重要价值。 相似文献
44.
45.
L.I. Daikhin M. Urbakh 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2003,560(1):59-67
We develop a theory of the double layer at electrolyte–electrolyte interfaces taking in to account the microscopic structure of the interfacial region. This includes a “mixed boundary layer” where the overlapping of two space-charge regions occurs, and the effects of ion association and adsorption at the interface. Theoretical results are in good agreement with experimental data obtained for various organic solvents and electrolytes. The theory suggests a framework for the treatment of the capacitance data and establishes a relationship between experimental results and the microscopic structure of interfaces between two immiscible electrolyte solutions (ITIES). 相似文献
46.
以液体稀释法比较了自制与进口十六烷基吡啶作用于4种口腔常见微生物的最低抑菌浓度和最低杀菌浓度的实验结果,经t检验证明两者间无显著差异,提示自制氯化十六烷基吡啶的药效质量可靠。并就控制接种菌量及杀菌机理等问题作了初步探讨。 相似文献
47.
Dr C. J. Whitters T. W. Macfarlane D. Mackenzie H. Moseley R. Strang 《Lasers in medical science》1994,9(4):297-303
Pulsed Nd-YAG laser irradiation of bacteria has been suggested as a possible means of treating contaminated intra-oral sites
although relatively few studies have been conducted. In this investigation, the antimicrobial activity of a pulsed Nd-YAG
laser was assessed in vitro for a range of oral bacteria using several pulse energies and exposure durations. Pure cultures
of each organism were lased in saline suspensions followed by standard colony counting techniques for test and control samples.
Microbial inhibition was found to be organism-dependent and varied with energy dose and pulse energy. For all nine test species
120-mJ laser pulses proved more efficient than 80-mJ pulses, with 99.9% kills compared with around 90% kills after exposure
to 1800 pulses. These killing activity levels compare favourably with those achieved with other lasers in vitro. 相似文献
48.
组织工程化口腔粘膜的构建技术初步研究 总被引:1,自引:0,他引:1
目的 探索组织工程化口腔粘膜的构建方法。方法 用 Dispase中性蛋白酶分离提取未长毛的 SD乳鼠硬腭口腔粘膜细胞 ,用角化细胞培养液对口腔粘膜细胞进行培养 ,以自制藻酸钠薄膜作为支架材料构建组织工程化的口腔粘膜。结果 Dispase中性蛋白酶可较好地分离提纯口腔粘膜细胞 ,用 Dispase消化酶分离获取上皮后 ,再用胰蛋白酶消化上皮为单细胞的最佳时间为 10 m in,过低的细胞密度不易形成克隆 ,鼠口腔粘膜细胞培养的最适密度为 1.5× 10 5/ cm2 。角化细胞培养液能对鼠口腔粘膜细胞进行培养 ,且没有成纤维细胞污染 ;口腔粘膜细胞在藻酸钠薄膜上生长良好。结论 利用角化细胞培养液作为培养基 ,藻酸钠薄膜作为支架材料可成功构建组织工程化口腔粘膜 相似文献
49.
Richard A. Meisch 《Pharmacology, biochemistry, and behavior》1995,50(4):571-580
The establishment of orally delivered etonitazene (a potent opioid) as a reinforcer, was studied in eight rhesus monkeys. Initially, when given concurrent access to 2.5 μg/ml etonitazene and the water vehicle, five of the monkeys rejected the drug, whereas the other three monkeys consumed more drug solution than water. The five monkeys that rejected the drug solution underwent an acquisition phase to establish the drug as a reinforcer. A fading procedure was used to transfer control of responding from a 2% (wt/vol) ethanol solution to a 2.5 μg/ml etonitazene solution. Initially, responding was maintained by contingent deliveries of 2% ethanol. Next, across blocks of six or more sessions, increasing amounts of etonitazene were added in steps to the 2% ethanol solution. Subsequently, the 2% ethanol solution was decreased in steps to zero, leaving only the 2.5 μg/ml etonitazene present. When the fading procedure was completed, dose of etonitazene was varied by increasing the volume delivered, first under fixed ratio (FR 4) and then under an FR 8 reinforcement schedule. The same dose manipulations were made with the three monkeys who did not undergo the fading procedure because they preferred etonitazene over water when first tested. Etonitazene was established as a reinforcer for six of the eight monkeys because drug deliveries exceeded vehicle deliveries across a range of drug doses. 相似文献
50.
Pyogenic infections of the central nervous system of dental origin are quite uncommon in industrialized countries. We report
six cases with intracerebral (n=4) and intraspinal (n=2) infections treated in our hospital. The microbial pathogen was successfully isolated in all patients. Fusobacterium nucleatum as well as Streptococcus species were found in three cases. Bacillus species were identified in two patients. Actinomyces was the etiologic agent in one case. All patients suffered from dental pathologies, so that after clinical and radiological
exclusion of other sources an oral focus was presumed. Therapeutic management consisted of an operative procedure in order
to obtain decompression, as well as evacuation of the pus on the one hand, followed by targeted antibiotics on the other.
Clinical improvement was achieved in all patients, with one patient lost to follow-up. On magnetic resonance tomography, the
inflammatory changes also disappeared in all cases. We recommend that oral infection with recurrent bacteraemia should always
be considered in the pathogenesis of the so-called “cryptic” intracerebral and intraspinal infections. 相似文献