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81.
目的为了分析血管抑素基因经肝动脉灌注后抑制肝癌的作用。方法将制作成功的Wistar大鼠肝癌模型随机分成4组,分别给予血管抑素基因、超液态碘油、血管抑素基因 碘油200μL质粒和脂质体复合物(含20μg质粒),对照组则组予0.9%生理盐水200μl。结果所有的治疗组均有一定的治疗效果,但基因与碘油相比差异并不显著。而基因 碘油的治疗效果明显好于其他各组。结论基因联合碘油可以明显提高抑制肝癌生长和转移的作用。  相似文献   
82.
目的:探讨中药香菊胶囊对生殖器疱疹(GH)豚鼠模型的影响。方法:选取Hartley雌性豚鼠30只,随机选取其中5只作为正常对照组,其余25只以人工感染单纯疱疹病毒2型(HSV-2)的方式建立GH动物模型,并随机分为模型对照组、阿昔洛韦组和香菊胶囊高、中、低剂量组,各组分别灌胃给药及给生理盐水后观察豚鼠发病情况和病程变化情况。结果:香菊胶囊治疗后GH豚鼠的皮损严重程度和消退时间较对照组明显降低,其中高剂量组效果最好,类似于阿昔洛韦组的用药效果,低剂量组效果最弱,中剂量组效果居中。香菊胶囊各剂量组豚鼠阴道内病毒滴度与阿昔洛韦组比较差异无统计学意义(P0.05)。结论:香菊胶囊能够抗HSV-2增殖,在豚鼠体内具有良好的抗HSV-2感染所致GH的作用。  相似文献   
83.
目的:观察归甲疏通胶囊对大鼠离体子宫平滑肌收缩的影响。选用健康未孕雌性成年大鼠40只,随机分为正常对照组,缩宫素模型组,归甲疏通胶囊高、中、低剂量组,除空白对照组外其他各组均采用缩宫素注射液人工造成动情期,以提高子宫敏感性。实验时处死大鼠并取出子宫,置于不同浓度的归甲疏通胶囊混悬液中,观察各组离体子宫张力、收缩强度、频率和活动力。结果:大鼠离体子宫平滑肌张力、强度、频率、活动力等指标,缩宫素模型对照组,归甲疏通胶囊高、中、低剂量组与空白对照组比较,差异均有统计学意义(P0.05);归甲疏通胶囊高、中、低剂量组与缩宫素模型对照组比较,差异均有统计学意义(P0.05);归甲疏通胶囊高、中、低剂量组组间比较差异也有统计学意义(P0.05)。大鼠离体子宫平滑肌张力、强度、频率、活动力等指标随着用药时间的延长逐渐降低。其中强度、频率、活动力用药各组用药10分钟、20分钟、30分钟时两两比较,差异均有统计学意义(P0.05)。大鼠离体子宫平滑肌张力归甲疏通胶囊高、中剂量组,用药10分钟、20分钟、30分钟时两两比较,差异均无统计学意义(P0.05);缩宫素模型对照组和归甲疏通胶囊低剂量组,用药10分钟时与用药20分钟、30分钟时比较,差异均有统计学意义(P0.05);用药20分钟时与用药30分钟时比较,差异也均有统计学意义(P0.05)。结论:归甲疏通胶囊可对抗缩宫素致大鼠离体子宫平滑肌的收缩,且有一定量效关系和时效关系。  相似文献   
84.
The effects of topical copaiba oil extract and topical corticosteroid were assessed on oral wound healing in an in vivo model using 96 male Wistar rats. Traumatic ulcers were caused in the dorsum of the tongue using a 3‐mm punch tool. The animals were divided into: Control; Corticosteroid; Placebo and Copaiba oil Group. The animals received two daily applications of the products. The control group received only daily handling. Six rats in each group were euthanized at days 3, 5, 10 and 14. The animals were monitored daily to determine wound status. The weigh was assessed at day 0 and euthanasia day. The percentage of repair was calculated, and histopathological aspects were analyzed. The Kruskal–Wallis test was used to compare the results between groups and times of evaluation. Closing time was assessed through the log‐rank test. The corticosteroid group lost more weight at days 10 and 14 than the control group (p < 0.05). Moreover, the healing time of corticosteroid group was longer than the control group (p = 0.007). No differences were observed between the copaiba oil group and the control group. We concluded that topical copaiba oil, in spite of being safe, did not accelerate the process of oral wound healing. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
85.
Chronic periodontitis is characterized by the destruction of the tissues supporting the teeth and has been associated with the presence of a subgingival polymicrobial biofilm containing Porphyromonas gingivalis and Treponema denticola. We have investigated the potential synergistic virulence of P. gingivalis and T. denticola using a murine experimental model of periodontitis. An inoculation regime of four intra-oral doses of 1 × 10(10) P. gingivalis cells induced significant periodontal bone loss compared with loss in sham-inoculated mice, whereas doses of 1 × 10(9) cells or lower did not induce bone loss. Inoculation with T. denticola with up to eight doses of 1 × 10(10) cells failed to induce bone loss in this model. However, four doses of a co-inoculum of a 1 : 1 ratio of P. gingivalis and T. denticola at 5 × 10(8) or 1 × 10(9) total bacterial cells induced the same level of bone loss as four doses of 1 × 10(10) P. gingivalis cells. Co-inoculation induced strong P. gingivalis-specific T-cell proliferative and interferon-γ-dominant cytokine responses, and induced a strong T. denticola-specific interferon-γ dominant cytokine response. Only at the higher co-inoculum dose of 1 × 10(10) total cells was a T. denticola-specific T-cell proliferative response observed. These data show that P. gingivalis and T. denticola act synergistically to stimulate the host immune response and to induce alveolar bone loss in a murine experimental periodontitis model.  相似文献   
86.
The purpose of this study was twofold: first, to determine the influence on the healing of the periapical tissues when selected bacterial strains and combinations thereof remain after root canal treatment; and, second, the relationship to healing of the quality of the root filling. In eight monkeys, 175 root canals, previously infected with combinations of four or five bacterial strains and with radiographically verified apical periodontitis, were endodontically treated, bacteriologically controlled, and permanently obturated. After 2-2.5 yr, the periapical regions were radiographically and histologically examined. Of these teeth, 48 root canals were also examined for bacteria remaining after removal of the root fillings. When bacteria remained after the endodontic treatment, 79% of the root canals showed non-healed periapical lesions, compared with 28% where no bacteria were found. Combinations of residual bacterial species were more frequently related to non-healed lesions than were single strains. When no bacteria remained, healing occurred independently of the quality of the root filling. In contrast, when bacteria remained, there was a greater correlation with non-healing in poor-quality root fillings than in technically well-performed fillings. In root canals where bacteria were found after removal of the root filling, 97% had not healed, compared with 18% for those root canals with no bacteria detected. The present study demonstrates the importance of obtaining a bacteria-free root canal system before permanent root filling in order to achieve optimal healing conditions for the periapical tissues.  相似文献   
87.
T-cell cytokine profiles, anti-Porphyromonas gingivalis antibodies and Western blot analysis of antibody responses were examined in BALB/c, CBA/CaH, C57BL6 and DBA/2J mice immunized intraperitoneally with different doses of P. gingivalis outer membrane antigens. Splenic CD4 and CD8 cells were examined for intracytoplasmic interleukin (IL)-4, interferon (IFN)-gamma and IL-10 by FACS analysis and levels of anti-P. gingivalis antibodies in the serum samples determined by enzyme-linked immunosorbent assay. Western blot analysis was performed on the sera from mice immunized with 100 microg of P. gingivalis antigens. The four strains of mice demonstrated varying degrees of T-cell immunity, although the T-cell cytokine profiles exhibited by each strain were not affected by different immunizing doses. While BALB/c and DBA/2J mice exhibited responses that peaked at immunizing doses of 100-200 microg of P. gingivalis antigens, CBA/CaH and C57BL6 demonstrated weak T-cell responsiveness compared with control mice. Like the T-cell responses, serum antibody levels were not dose dependent. DBA/2J exhibited the lowest levels of anti-P. gingivalis antibodies followed by BALB/c with CBA/CaH and C57BL6 mice demonstrating the highest levels. Western blot analysis showed that there were differences in reactivity between the strains to a group of 13 antigens ranging in molecular weight from 15 to 43 kDa. Antibody responses to a number of these bands in BALB/c mice were of low density, whereas CBA/CaH and C57BL6 mice demonstrated high-density bands and DBA/2J mice showed medium to high responses. In conclusion, different immunizing doses of P. gingivalis outer membrane antigens had little effect on the T-cell cytokine responses and serum anti-P. gingivalis antibody levels. Western blot analysis, however, indicated that the four strains of mice exhibited different reactivity to some lower-molecular-weight antigens. Future studies are required to determine the significance of these differences, which may affect the outcome of P. gingivalis infection.  相似文献   
88.
Aim: To evaluate the influence (i) of various implant platform configurations and (ii) of implant surface characteristics on peri‐implant tissue dimensions in a dog model. Material and methods: Mandibular premolars and first molars were extracted bilaterally in six Labrador dogs. After 3 months of healing, two implants, one with a turned and a second with a moderately rough surface, were installed on each side of the mandible in the premolar region. On the right side of the mandible, implants with a tapered and enlarged platform were used, while standard cylindrical implants were installed in the left side of the mandible. Abutments with the diameter of the cylindrical implants were used resulting in a mismatch of 0.25 mm at the tapered implant sites. The flaps were sutured to allow a non‐submerged healing. After 4 months, the animals were sacrificed and ground sections were obtained for histometric assessment. Results: All implants were completely osseointegrated. A minimal buccal bone resorption was observed for both implant configurations and surface topographies. Considering the animals as the statistical unit, no significant differences were found at the buccal aspect in relation to bone levels and soft tissue dimensions. The surface topographies did not influence the outcomes either. Conclusions: The present study failed to show differences in peri‐implant tissue dimensions when a mismatch of 0.25 mm from a tapered platform to an abutment was applied. The surface topographies influence a neither marginal bone resorption or peri‐implant soft tissue dimension. To cite this article:
Baffone GM, Botticelli D, Pantani F, Cardoso LC, Schweikert MT, Lang NP. Influence of various implant platform configurations on peri‐implant tissue dimensions: an experimental study in dog.
Clin. Oral Impl. Res. 22 , 2011; 438–444.  相似文献   
89.
目的探讨经颧弓后上牵引下颌,建立颞下颌关节紊乱病(TMD)动物模型的可能性。方法21只新西兰大白兔(实验组15只,对照组6只),单侧经颧弓后上牵引下颌,观察关节盘、关节间隙及关节软骨的组织病理学改变。结果实验组术后2周4只动物关节盘移位或变形;4周时5只动物关节均发生粘连,关节软骨发生不同程度表层破裂、缺损或排列紊乱;6周时4只动物关节盘严重变形,5只动物关节发生严重粘连,骨小梁排列紊乱。对照组均正常。结论经颧弓后上牵引下颌是研究TMD病理机制一种较可靠的动物模型。  相似文献   
90.
OBJECTIVES: : To investigate infection and host immunity patterns in sheep with naturally occurring "broken-mouth" periodontitis. MATERIALS AND METHODS: : Eight periodontally healthy (HS) and eight periodontally diseased ewes (PDS) were selected. Subgingival plaque and sera were collected and examined for evidence of human periodontitis-associated pathogens. Serum IgG titers were measured by ELISA to multiple strains of Porphyromonas gingivalis, Bacteroides forsythus, Dichelobacter nodosus, Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Fusobacterium nucleatum as well as several purified antigens (cysteine proteases, LPS, K, and fimbriae). RESULTS: : Neither the organism Aa nor antigens to Aa were found in any animal. Most animals were positive for Pg, Bf, and Pi, but DNA probes detected no difference between HS and PDS relative to amounts of pathogens in subgingival plaque. PDS had significantly higher serum IgG titers to all Pg strains, to 50% of Bf strains, to the Pi and Fn strains, and to fimbriae and the two cysteine proteases (p-values ranging from 0.05 to 0.001). Regression analysis demonstrated a significant association between number of teeth lost and serum IgG antibody titers to whole-cell sonicate antigens of P. gingivalis strains (p<0.01) and body weight (p<0.01). CONCLUSIONS: : The presence of pathogens associated with periodontitis was reflected in differences in serum IgG titers between healthy and diseased sheep. This may have influenced animal body weight and might have systemic health and economic consequences. The data suggest that susceptible and non-susceptible sheep can be identified for periodontal research.  相似文献   
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