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The present study was designed to measure the durability of glass fiber-reinforced hybrid resins (FRC) in clinical applications. Accordingly, we studied the effects of static and dynamic loading as well as temperature changes inside the oral cavity, a moist environment, on the bending strength of FRC. The bending strength was measured using several tests, including an open-air bending strength test (AE), a 24-h water immersion test (WC1D), a 2-year water immersion test (WC2Y), a thermal cycling test (TC), a repeated in-water impact test at 37°C/10(5) (WI37), and a repeated in-water impact test at 55°C/10(5) (WI55). The following tests are ordered from greatest to least with respect to GF's bending strength: AE, WI37, WI55, WC1D, WC2Y, and TC. Likewise, the following tests are ordered from greatest to least with respect to EV's bending strength: AE, WC1D, WC2Y, WI37, WI55, and TC.  相似文献   
93.
The aim of this study was to investigate mineralizing ability of a premixed calcium phosphate cement (premixed-CPC) compared to mineral trioxide aggregate (MTA) and zinc oxide eugenol cement (SuperEBA) in ROS17/2.8 cells. The measurements of cell proliferation, alkaline phosphatase (ALPase) activity and mineralized nodule formation in the presence or absence (control) of the test materials were performed using a cell culture insert method with the test materials placed on a porous membrane of culture plate insert. Mineralized nodules were detected by staining with alizarin red, and the calcium content of the mineralized nodules was determined quantitatively using a calcium assay kit. Premixed-CPC and MTA indicated significantly higher cell proliferation, ALPase activity, mineralized nodule formation, and calcium content in nodules than those of SuperEBA (p<0.05). The present results suggest that premixed-CPC has the same mineralizing ability as MTA.  相似文献   
94.
Insulin signalling system and mechanism of insulin resistance   总被引:6,自引:0,他引:6  
Insulin exerts wide variety of biological effects through interaction with its specific receptor, which belongs to a large family of receptor tyrosine kinases. The activated insulin receptor phosphorylates the intracellular substrate IRS protains, which then bind various signalling molecules that contain Src homology 2 domains. The first downstram molecule that was shown to associate with IRS protains is PI3-kinase. PI3-kinase contributes to a wide variety of biological actions. Both Akt(PKB), a serine-threonine kinase with a PH domain, and atypical PKC(PKC zeta, PKC lambda) have been implicated as downstream effectors of PI3-kinase. Insulin resistance contributes to the pathogenesis of NIDDM. Both primary, genetically, and secondary, environmentally factors are important for insulin resistance. The secondary factors include hyperglycemia, hyperlipidemia, obesity, TNF alpha, FFA(free fatty acid).  相似文献   
95.
An 11‐year‐old boy presented with fever and abdominal pain, and was diagnosed with retroperitoneal lymphadenitis. At the same time, a painless right scrotal mass was observed. On imaging the testis and the epididymal mass both had abundant blood flow, although tumor markers were negative. Although the right testis had shrunk after antibiotic treatment, swelling was persistent and incisional biopsy was therefore performed, resulting in diagnosis of granulomatous orchitis (GO). No recurrence was found. In cases of scrotal swelling in both the testis and the epididymis of an older child, it is necessary to consider the possibility of inflammatory GO, and orchiectomy should not be performed without careful consideration.  相似文献   
96.
The recently identified endogenous peptide apelin and its specific apelin receptor (APJ) are currently being considered as potential regulators in vascular tissue. Previously, we reported apelin mediates phosphorylation of myosin light chain and elicits vasoconstriction in vascular smooth muscle. In this study, physiological roles of the apelin-APJ system were investigated on atherosclerosis. In APJ and apolipoprotein E double-knockout (APJ(-/-)ApoE(-/-)) mice fed a high-cholesterol diet, atherosclerotic lesions were dramatically reduced when compared with APJ(+/+) ApoE(-/-) mice, in the absence of an effect of cholesterol levels. Immunohistochemical detection of smooth muscle cells, using a smooth muscle alpha-actin antibody, showed greatly reduced staining for these cells in lesions of APJ(-/-)ApoE(-/-) mice fed a high-cholesterol diet. Vascular production of superoxide radicals and the expression of nicotinamide-adenine dinucleotide phosphate oxidase subunits were decreased in APJ(-/-)ApoE(-/-) mice compared with APJ(+/+)ApoE(-/-) mice fed a standard normal diet. In vascular smooth muscle cells, apelin induced nicotinamide-adenine dinucleotide phosphate oxidase subunit expression. Apelin also induced vascular smooth muscle cell proliferation, which was inhibited by superoxide dismutase or diphenylene iodonium. The apelin-APJ system is a mediator of oxidative stress in vascular tissue, and thus we propose it to be a critical factor in atherogenesis under high-cholesterol dietary conditions. APJ deficiency is preventative against oxidative stress-linked atherosclerosis.  相似文献   
97.
Several species of bisphosphonate (BP) have been widely used as one of the standardized supportive therapy for myeloma patients, because of the efficacy evidenced by lots of prospective randomised trials showing the decreased incidence of the skeletal-related events. In addition, BPs have lots of beneficial effects on myeloma patients, including the enhancement of lymphocyte subset, and anti-myeloma effects possibly by 'indirect' effects on myeloma cells via apoptosis-inducing effects on osteoclasts, as well as 'direct' apoptosis -inducing effects on myeloma cells. On the contrary, BPs have been shown to have adverse events, including transient flu -like syndrome accompanied by fever and transient inflammatory reactions, and unexpected severe tissue damage, named 'osteonecrosis of the jaw (ONJ)'. Once ONJ developed in myeloma patients, myeloma therapies could be influenced drastically at times, because ONJ site could become infection focus and necessitate cessation of cytotoxic therapy in order to support tissue repair in situ. Prevention of ONJ might be feasible through oral hygiene, because ONJ develops almost always in patients with long-history of dental diseases.  相似文献   
98.
Forward dislocation of the temporomandibular joint commonly can be easily diagnosed and successfully reduced by manual repositioning. In this report, we discuss a rare case of prolonged temporomandibular dislocation that had persisted for more than 20 years because the otolaryngologist and dentist had missed the dislocation. This patient underwent open reduction and mandibular joint plasty with preoperative orthodontic therapy. It is possible that strong pain and mouth-closing disability may gradually remit and only deviated mandibular prognathism like malocclusion may persist. Therefore, abnormal occlusion warrants careful attention to temporomandibular joint dislocation.  相似文献   
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