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991.
The present investigation deals with the effect of the chloroform fraction composed of sterols and fatty acids isolated from Hemidesmus indicus root extract (CHI) on Salmonella enterica serovar Typhimurium (S. typhimurium)-induced cytotoxicity in a human intestinal epithelial cell line (Int 407). The optimum dose was fixed as 100 microg/mL for CHI against S. typhimurium, which was quite safe for Int 407 cells as the CD(50) concentration (50% cell death) of CHI was determined to be 500 microg/mL in the Int 407 cell line. CHI-treated S. typhimurium were 10-fold less cytotoxic and 40% less adherent to host cells than wild-type. Treatment of CHI significantly abrogated the invasion ability to 10- to 15-fold in S. typhimurium. The cells infected with CHI-treated S. typhimurium had a comparable viability to uninfected cells in the epithelial cell detachment assay. Immunofluorescence showed the CHI-treated bacteria were unhealthy and shrunken rods in comparison with the wild-type bacteria; those were firmly attached and invaded to deceased and hypertrophoid Int 407 cells. Transmission electron micrographs of Int 407 cells infected with wild bacteria showed a coat of adherent and invaded bacteria completely occupying the cytoplasm with characteristic Salmonella-containing vacuoles (SCV). Both necrotic and apoptotic type of cell death were observed in cells infected with wild-type bacteria, whereas most of the cells infected with treated bacteria were normal in morphology and a few had invaded bacteria, but the typical proliferated SCV was not observed in cells infected with CHI-treated S. typhimurium. In summary, the sterols and fatty acids present in CHI may be capable of taming S. typhimurium by suppressing its cytotoxic activity in an intestinal epithelial cell line. 相似文献
992.
补肾、益气中药对哮喘模型大鼠神经内分泌免疫网络若干指标的影响 总被引:6,自引:2,他引:4
目的 观察补肾(淫羊藿)和益气(黄芪)中药对哮喘反复发作模型大鼠神经内分泌免疫(neuroendocrino-immune,NEI)网络相关指标变化的影响.方法 将健康清洁级雄性挪威(Brown Norway,BN)大鼠120只,分为11组,采用Realtime-PCR法检测下丘脑促肾上腺激素释放激素(CRH)mRNA的表达;放免法检测血浆中促肾上腺皮质激素(ACTH)的含量;酶联免疫吸附实验(ELISA)检测血清白细胞介素-4(IL-4),IL-6,干扰素-γ(IFN-γ)和皮质酮(CORT)的含量;采用HE染色法观察肺组织病理变化.结果 与正常对照组比较,哮喘反复发作3周模型大鼠下丘脑CRHmRNA表达和血浆ACTH无明显变化,血清CORT水平升高显著,IFN-γ无明显变化,前炎症因子IL-6、IL-4有上升趋势;与哮喘对照组比较,复方中、高剂量组和淫羊藿低、中剂量组下丘脑CRH mRNA的表达明显升高,淫羊藿中剂量组大鼠血清IFN-γ的浓度升高.黄芪低剂量组大鼠血清CORT的浓度升高,黄芪高剂量组血清IL-4和IL-6的浓度降低.结论 哮喘反复发作3周大鼠存在NEI网络若干指标的紊乱;补肾和益气中药可以增强下丘脑-垂体-肾上腺皮质(hypothalamic-pituitary-adrenal,HPA)轴的功能,还可以改变Th1和Th2型细胞因子的平衡,这些可能是其治疗哮喘反复发作的机制之一. 相似文献
993.
目的:评价混合技术法对根管预备的临床疗效。方法:91颗患牙分为两组,实验组45颗牙85个根管,采用混合技术进行根管预备,对照组46颗牙92个根管,采用逐步后退技术预备根管,两组均采用冷侧压技术充填根管。X线片结合临床评价根管预备效果。结果:实验组根管未有锥度、流畅度差者,对照组有5根管锥度、流畅度差者(P〈0.05);术后疼痛实验组少于对照组。结论:混合技术法进行根管预备可形成大锥度、流畅根管形态,减少术后疼痛,可视为临床根管预备的有效方法。 相似文献
994.
����ϼ��κٲ�࣬��������ѩ���ھ��� 《中国实用口腔科杂志》2016,9(10):628-631
??An isthmus is defined as a narrow ribbon-shaped structure between two root canals that contains pulp tissues. It can be a bacterial reservoir which is difficult to prepare??shape and fill??which accounts for the failure of root canal therapy. In this paper??the root canal isthmus were reviewed. 相似文献
995.
Cone-beam computed tomography (CBCT) has been widely used in diagnosis of vertical root fractures (VRFs) in recent years. According to the American Association of Endodontists (AAE) classification, there are five types of cracked teeth and VRF is one of them. Due to the variability and overlapping of the cracks and fractures, some narrow fractures on the roots of VRFs could not be detected by CBCT, and some wide cracks on the crown of cracked teeth could be detected by CBCT. In this review, we firstly discussed the value of CBCT in the diagnosis of the AAE five types of cracked teeth and presented CBCT manifestations of some typical cases. Secondly, we summarized the factors influencing the diagnosis of cracks/fractures using CBCT, namely, CBCT device-related factors, patient-related factors, and evaluator-related factors. The possible strategies to improve the diagnostic accuracy in the clinic practice are also discussed in this part. Finally, we compared the differences of root fractures with lateral canals and external root resorption on CBCT images. 相似文献
996.
目的 评价C+锉应用于磨牙根管再治疗其疏通根管的临床效果。方法 选取需根管再治疗的磨牙60颗,随机分成2组,分别用C+锉和不锈钢K锉进行根管疏通,机用ProTaper完成根管预备并垂直加压充填,X线片评价根管疏通的效果。结果 C+锉疏通根管的成功率高于不锈钢K锉(P <0.05),为87.7%。结论 C+锉在磨牙根管再治疗中有良好的疏通效果,但应注意预防根管侧穿。
相似文献997.
Initial outcome and long-term effect of surgical and non-surgical treatment of advanced periodontal disease 总被引:3,自引:0,他引:3
G. Serino B. Rosling P. Ramberg S. S. Socransky J. Lindhe 《Journal of clinical periodontology》2001,28(10):910-916
AIM: A clinical trial was performed to determine (i) the initial outcome of non-surgical and surgical access treatment in subjects with advanced periodontal disease and (ii) the incidence of recurrent disease during 12 years of maintenance following active therapy. MATERIAL AND METHODS: Each of the 64 subjects included in the trial showed signs of (i) generalized gingival inflammation, (ii) had a minimum of 12 non-molar teeth with deep pockets (> or =6 mm) and with > or =6 mm alveolar bone loss. They were randomly assigned to 2 treatment groups; one surgical (SU) and one non-surgical (SRP). Following a baseline examination, all patients were given a detailed case presentation which included oral hygiene instruction. The subjects in SU received surgical access therapy, while in SRP non-surgical treatment was provided. After this basic therapy, all subjects were enrolled in a maintenance care program and were provided with meticulous supportive periodontal therapy (SPT) 3-4 times per year. Sites that at a recall appointment bled on gentle probing and had a PPD value of > or =5 mm were exposed to renewed subgingival instrumentation. Comprehensive re-examinations were performed after 1, 3, 5 and 13 years of SPT. If a subject between annual examinations exhibited marked disease progression (i.e., additional PAL loss of > or =2 mm at > or =4 teeth), he/she was exited from the study and given additional treatment. RESULTS: It was observed that (i) surgical therapy (SU) was more effective than non-surgical scaling and root planing (SRP) in reducing the overall mean probing pocket depth and in eliminating deep pockets, (ii) more SRP-treated subjects exhibited signs of advanced disease progression in the 1-3 year period following active therapy than SU-treated subjects. CONCLUSION: In subjects with advanced periodontal disease, surgical therapy provides better short and long-term periodontal pocket reduction and may lead to fewer subjects requiring additional adjunctive therapy. 相似文献
998.
Human histology of new attachment after root coverage using subepithelial connective tissue graft 总被引:1,自引:0,他引:1
M. Goldstein B. D. Boyan D. L. Cochran Z. Schwartz 《Journal of clinical periodontology》2001,28(7):657-662
BACKGROUND, AIMS: Connective tissue grafts are used successfully in periodontal therapy for root coverage. However, reports on the histologic interface between the root surface and the grafted tissue have been few in number. This report describes a case study in which a subepithelial connective tissue graft was placed in a 27-year-old female on the maxillary left side. METHODS: The graft (15 mm long, 10 mm wide, 1.5 mm thick) included palatal periosteum and was placed with the periosteal side facing the exposed bone and root surfaces. RESULTS: 15 weeks after grafting, the teeth presented with residual recessions of 1 mm, and buccal probing depths were approximately 1 mm. 14 months post-surgery, the 1st maxillary premolars on both sides were extracted for orthodontic therapy. Clinical parameters at the graft site remained as at 15 weeks. Histologic analysis of tooth #24 showed that the sulcular epithelium was keratinized; epithelium lining the dentin exhibited rete ridges projecting into the gingival connective tissue; and junctional epithelium extended over new cementum. New connective tissue attachment was also observed, including periodontal ligament. CONCLUSION: Biological width was comparable pre- and post-surgery, indicating a real gain in attachment of 3.9 mm. 相似文献
999.
1000.
眶上神经痛是一种眼科常见病,多继发于感冒,主要表现为眶内上方疼痛、前额疼痛,多伴有眩晕、恶心、呕吐,眶上切迹压痛明显,复发率高。我科根据患者发病时症状,结合患者自身情况,辨证施治:利用仲景方葛根加半夏汤治疗,方以桂枝汤加麻黄、葛根组成,有解肌发汗、舒经止痛的作用,疗效满意,且能明显降低愈后复发率。 相似文献