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991.
This study analyzed the influence of C-factor, flexural modulus and viscous flow on gap formation in resin composite restorations. Two resin composites, a mini-filled hybrid (P 60) and a nanofilled (Supreme), were used. The flexural modulus was obtained from bar-shaped specimens submitted to three-point bending. Viscous flow was obtained from the difference between the initial and final diameter of resin composite disks submitted to a load of 10 N for 120 seconds. Gap analysis was conducted in three types of cylindrical cavities (C-factor of 1.8, 2.6 and 3.4) that were prepared on the occlusal surfaces of human molars. The gap width at the dentin-resin composite interface was measured using a 3D scanning system (Talyscan 150). The data were analyzed by ANOVA and Student-Newman-Keuls' test, t-test and linear regression analysis (alpha = 0.05). The cavities with C-factor 3.4 presented the highest Gap formation (p < 0.0001). The lowest Gap formation was found in cavities restored with Supreme resin composite (p < 0.0001). P 60 presented significantly higher flexural modulus and lower viscous flow than Supreme (p < 0.0001). Regression analyses detected a significant influence of flexural modulus and viscous flow on gap formation (p < 0.05).  相似文献   
992.
993.
994.
Oncogenic human papillomaviruses (HPVs) are important agents in the genesis of gynecological cancer, and have also been implied in the genesis of oral cancer. With the purpose of evaluating the relationship between HPV and squamous cell carcinoma (SCC) of the tongue, a case-control study was performed. Fifty white male patients who were smokers and had the histological diagnosis of SCC of the tongue were selected. The control group was composed of 10 matched patients with no clinical evidence of tongue lesions. Polymerase chain reaction (PCR) was used to detect the presence of HPV genome in fresh-frozen tissue specimens from SCC of the tongue margin. Thirty-seven patients (74%) had a positive PCR for oncogenic papillomavirus, and only 1 specimen (10%) of the control group was positive for nononcogenic papillomavirus. Based on the statistical analysis of this study there was a 25.6% higher risk for SCC of the tongue to harbor oncogenic HPV than the healthy control tongue tissue.  相似文献   
995.

Background

The aim of this study was to investigate this involvement in not inflammatory model of pain and which opioid receptor subtype mediates noradrenaline-induced peripheral antinociception. Noradrenaline is involved in the intrinsic control of pain-inducing pro-nociceptive effects in the primary afferent nociceptors. However, inflammation can induce various plastic changes in the central and peripheral noradrenergic system that, upon interaction with the immune system, may contribute, in part, to peripheral antinociception.

Methods

Hyperalgesia was induced by intraplantar injection of prostaglandin E2 (PGE2, 2 μg) into the plantar surface of the right hind paw and the paw pressure test to evaluated the hyperalgesia was used. Noradrenaline (NA) was administered locally into right hind paw of Wistar rat (160–200 g) alone and after either agents, α2-adrenoceptor antagonist yohimbine, α1-adrenoceptor antagonist prazosin, β-adrenoceptor antagonist propranolol, μ-opioid antagonist clocinnamox, δ-opioid antagonist naltrindole and κ-opioid antagonist nor-binaltorfimina. In addition, the enkephalinase inhibitor bestatin was administered prior to NA low dose.

Results

Intraplantar injection of NA induced peripheral antinociception against hyperalgesia induced by PGE2. This effect was reversed, in dose dependent manner, by intraplantar injection of yohimbine, prazosin, propranolol, clocinnamox and naltrindole. However, injection of nor-binaltorfimina did not alter antinociception of NA after PGE2 hyperalgesia. Bestatin intensified the antinociceptive effects of low-dose of NA.

Conclusion

Besides the α2-adrenoceptor, the present data provide evidence that, in absence of inflammation, NA activating α1 and β-adrenoceptor induce endogenous opioid release to produce peripheral antinociceptive effect by μ and δ opioid receptors.  相似文献   
996.
International Urology and Nephrology - Recent studies have shed light on the potential role of curcumin in mitigating inflammation in patients with chronic kidney disease (CKD). This study aimed to...  相似文献   
997.
Lasers in Medical Science - The benefits of photobiomodulation (PBM) applied to wounds are well-described in the literature; however, its effects in skin graft donor sites have been poorly studied....  相似文献   
998.
Lasers in Medical Science - This narrative review aimed to evaluate the effectiveness of PDT in early or advanced squamous cell carcinoma of the head and neck (SCCHN). Scopus, MEDLINE/PubMed, and...  相似文献   
999.
Neurosurgical Review - Traumatic brain injury (TBI) is the main cause of pediatric trauma death and disability worldwide. Recent studies have sought to identify biomarkers of TBI for the purpose of...  相似文献   
1000.
Neurological Sciences - Episodic memory impairment may occur in progressive supranuclear palsy (PSP). However, it remains uncertain whether this is due to executive dysfunction or to the...  相似文献   
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