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991.
Background: The innervation of skin and oral mucosa plays a major physiological role in exteroception. This innervation is also clinically relevant as sensory changes occur after neurosurgical procedures. Purpose: The goal of this study was to compare the perception of mechanical stimuli applied to the buccal mucosa in the vicinity of osseointegrated oral implants with that in the controlateral dentate side. The role of the previously reported increased innervation in the peri‐implant soft tissues in the oral sensorimotor function was thus examined. Materials and Methods: Seventeen subjects with 20 implants were tested. Directional cutaneous kinaesthesia (DCK) and graphesthesia (G) were performed on the buccal side of the alveolar mucosa before and at planned intervals after implant placement. The observation was pursued until 6 months after the prosthetic rehabilitation. In each subject, the contralateral mucosa served as a control to the implant sites. Average percentages of correct responses in a four‐choice task for DCK and a three‐choice task for G were calculated. Results: Despite an intersubject variation in both the DCK and G, high intraindividual correlations were found (p < .005). The implant sites showed a significant difference toward the control sites at the four interval test for both tests. For DCK and G, the average of correct responses decreased after abutment connection (i.e., after the implant uncovering surgery) to increase afterwards to reach a level close to, but still lower than, the control sites 3 to 6 months after the prosthetic rehabilitation. Conclusion: The DCK and G are simple but reliable sensory tests that can be easily applied in the oral region. This prospective study indicates that tooth loss reduces tactile function compared with implant‐supported prostheses. The peri‐implant soft tissues could be partially involved in the osseoperception function.  相似文献   
992.

Objective

The aim of this study was to evaluate the effect of multiple layers of an infection control barrier on the micro-hardness of a composite resin.

Material and Methods

One, two, four, and eight layers of an infection control barrier were used to cover the light guides of a high-power light emitting diode (LED) light curing unit (LCU) and a low-power halogen LCU. The composite specimens were photopolymerized with the LCUs and the barriers, and the micro-hardness of the upper and lower surfaces was measured (n=10). The hardness ratio was calculated by dividing the bottom surface hardness of the experimental groups by the irradiated surface hardness of the control groups. The data was analyzed by two-way ANOVA and Tukey''s HSD test.

Results

The micro-hardness of the composite specimens photopolymerized with the LED LCU decreased significantly in the four- and eight-layer groups of the upper surface and in the two-, four-, and eight-layer groups of the lower surface. The hardness ratio of the composite specimens was <80% in the eight-layer group. The micro-hardness of the composite specimens photopolymerized with the halogen LCU decreased significantly in the eight-layer group of the upper surface and in the two-, four-, and eight-layer groups of the lower surface. However, the hardness ratios of all the composite specimens photopolymerized with barriers were <80%.

Conclusions

The two-layer infection control barrier could be used on high-power LCUs without decreasing the surface hardness of the composite resin. However, when using an infection control barrier on the low-power LCUs, attention should be paid so as not to sacrifice the polymerization efficiency.  相似文献   
993.
OBJECTIVE: P-113, a 12 amino acid histatin-based peptide, was evaluated in a mouthrinse formulation for safety and efficacy in a phase 2 multi-center clinical study. METHOD: 294 healthy subjects abstained from oral hygiene procedures and self-administered either 0.01% P-113, 0.03% P-113 or placebo mouthrinse formulations twice daily over a 4-week treatment period. During this time, the safety, anti-gingivitis, and anti-plaque effects of P-113 were evaluated. RESULTS: There was a significant reduction in the change from baseline to Day 22 in bleeding on probing in the 0.01% P-113 treatment group of the intent to treat population (p=0.049). Non-significant trends in the reduction of the other parameters were observed in this population (p> or =0.159). A sub-group of subjects which developed significant levels of disease within the four-week timeframe of the study was identified based on baseline gingival index scores > or =0.75. Significant findings were observed for bleeding on probing, gingival index and plaque index within this population (p<0.05). There were no treatment-related adverse events, and there were no adverse shifts in supragingival microflora during the study. Significant amounts of the peptide were retained in the oral cavity following rinsing. CONCLUSION: These data suggest that P-113 mouthrinse is safe and reduces the development of gingival bleeding, gingivitis and plaque in the human experimental gingivitis model.  相似文献   
994.
995.
996.
In this study, different phenolic extracts were obtained from the jaboticaba skin meal (JSM), whose phenolic compounds were characterized and their antibacterial activities were assessed. Moreover, the activity of lyophilized ethanolic extract of jaboticaba skin (EEJS) on wound healing was analyzed in rats. The JSM phenolic extracts were obtained in four ways: aqueous, methanolic, ethanolic, and acetone extracts. The phenolic compounds were characterized in these extracts by high‐performance liquid chromatography, and their antibacterial activities were evaluated. The in vivo experiment was divided into four groups and received the following treatments: G1—silver sulfadiazine (positive control); G2—EEJS at 10%; G3—EEJS at 5%, and G4—EEJS at 2.5%. The aqueous extract did not inhibit the growing of any bacterium. The ethanolic, acetone, and methanolic extracts inhibited the growing of all bacteria tested at the concentrations of 1.25%, 2.50%, and 5.00%, respectively. The ethanolic extract was the one that showed the highest bacterial inhibition potential and the highest contents of phenolic compounds, especially of catechin, epicatechin gallate, and epicatechin. The G3 and G4 treatments presented faster wound healing compared to the G1 one, as it promoted a less intense inflammatory reaction and full closure of the wounds at an accelerated rate.  相似文献   
997.
The notion of testing for equivalence of two treatments is widely used in clinical trials, pharmaceutical experiments, bioequivalence, and quality control. It is essentially approached within the intersection-union (IU) principle. According to this principle, the null hypothesis is stated as the set of effects lying outside a suitably established interval and the alternative as the set of effects lying inside that interval. The solutions provided in the literature are mostly based on likelihood techniques, which in turn are rather difficult to handle, except for cases lying within the regular exponential family and the invariance principle. The main goal of the present article is to go beyond most of the limitations of likelihood-based methods, that is, to work in a nonparametric setting within the permutation frame. To obtain practical solutions, a new IU permutation test is presented and discussed. A simple simulation study for evaluating its main properties, and three application examples are also presented.  相似文献   
998.
李婵  陈楠 《天津医药》2018,46(11):1205-1208
摘要: 目的 了解我院儿童患者2013—2017年临床分离的耐碳青霉烯肠杆菌 (CRE) 的分布及耐药情况, 为控制和治疗此类菌引起的感染提供用药依据。方法 采用VITEK 2 Compact全自动微生物鉴定药敏仪对该类细菌进行药敏实验, 参考CLSI-M100折点标准, WHONET5.6软件进行结果分析, 采用χ2 检验进行统计分析。结果 2013— 2017年, 临床共分离出687株CRE菌株, 总检出率10.64%。主要为肺炎克雷伯菌 (302株)、 大肠埃希菌 (213株)、 奇异变形杆菌 (72株)。5年的CRE检出率基本呈上升趋势, 标本主要来源于尿液 (38.14%), 其次为呼吸道 (30.13%)。 CRE菌株对氨基糖苷类和喹诺酮类抗菌药物耐药率<30%, 但对其他β-内酰胺类药物耐药率则基本在70%以上。结论 CRE菌株在儿童患者感染中呈逐年上升趋势, 并大多表现为多药耐药菌株。  相似文献   
999.
Persistent pain remains a major health issue: common treatments relying on either repeated local injections or systemic drug administration are prone to concomitant side-effects. It is thought that an alternative could be a multifunctional cargo system to deliver medicine to the target site and release it over a prolonged time window. We nano-engineered microcapsules equipped with adjustable cargo release properties and encapsulated the sodium-channel blocker QX-314 using the layer-by-layer (LbL) technology. First, we employed single-cell electrophysiology to establish in vitro that microcapsule application can dampen neuronal excitability in a controlled fashion. Secondly, we used two-photon excitation imaging to monitor and adjust long-lasting release of encapsulated cargo in target tissue in situ. Finally, we explored an established peripheral inflammation model in rodents to find that a single local injection of QX-314-containing microcapsules could provide robust pain relief lasting for over a week. This was accompanied by a recovery of the locomotive deficit and the amelioration of anxiety in animals with persistent inflammation. Post hoc immunohistology confirmed biodegradation of microcapsules over a period of several weeks. The overall remedial effect lasted 10–20 times longer than that of a single focal drug injection. It depended on the QX-314 encapsulation levels, involved TRPV1-channel-dependent cell permeability of QX-314, and showed no detectable side-effects. Our data suggest that nano-engineered encapsulation provides local drug delivery suitable for prolonged pain relief, which could be highly advantageous compared to existing treatments.  相似文献   
1000.
目的 探讨不同年龄阿尔茨海默病(AD)患者ADC值与年龄的相关性。方法 选取30例AD患者(AD组)和年龄与之相匹配的30名志愿者(对照组),按年龄段各分为6个亚组[55~59岁(n=3)、60~64岁(n=4)、65~70岁(n=9)、71~74岁(n=5)、75~80岁(n=6)、>80岁(n=3)],测量双侧海马、红核、尾状核、杏仁体、壳核ADC值,并进行配对t检验、独立样本t检验、单因素方差分析及Pearson相关分析。结果 AD组红核左、右侧ADC值有统计学差异(P=0.022)。AD组不同年龄亚组右侧海马、双侧尾状核、右侧壳核ADC值差异有统计学意义(P均<0.05);2组不同年龄亚组双侧海马、壳核、尾状核ADC值差异有统计学意义(P均<0.05)。AD组右侧海马(r=0.615,P<0.001)、右侧壳核(r=0.653,P=0.001)及双侧尾状核(左侧:r=0.397,P=0.030;右侧:r=0.429,P=0.020)ADC值与年龄呈正相关。结论 AD患者右侧海马和壳核、双侧尾状核ADC值随年龄增加而增大。ADC值可为临床预测和早期诊断AD脑内右侧海马和壳核、双侧尾状核神经退行性病变提供参考。  相似文献   
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