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51.
A recent development within burnout research is the shift to its conceptual opposite: work engagement. This study aimed to unravel the concepts of burnout and work engagement, and to determine their levels among dentists. A representative sample of 497 Dutch general dental practitioners was included (survey response rate of 59%), consisting of 372 men and 121 women (the gender of 4 dentists remained unknown). The hypothesized three-factor structure of work engagement (vigor, dedication, and absorption), as measured by the Utrecht Work Engagement Scale (UWES), was substantiated among dentists. It was also found that work engagement was related negatively to burnout, as measured by the Maslach Burnout Inventory (MBI). However, a model consisting of a reduced ('core') burnout factor and an 'enhanced' engagement factor (composed of the three original factors plus the burnout factor, personal accomplishment) showed the best fit. Overall burnout levels among dentists are low, and the levels of engagement indicate that dentists have a positive working attitude.  相似文献   
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With the extensive application of titanium dioxide (TiO2) nanoparticles (NPs) in food industry, there is a rising debate concerning the possible risk associated with exposure to TiO2 NPs. The purpose of this study is to evaluate the genotoxicity of TiO2 NPs using in vivo and in vitro test systems. In vivo study, the adult male Sprague-Dawley rats were exposed to anatase TiO2 NPs (75 ± 15 nm) through intragastric administration at 0, 10, 50 and 200 mg/kg body weight every day for 30 days. The γ-H2AX assay showed TiO2 NPs could induce DNA double strand breaks in bone marrow cells after oral administration. However, the micronucleus test revealed that the oral-exposed TiO2 NPs did not cause damage to chromosomes or mitotic apparatus observably in rat bone marrow cells. In vitro study, Chinese hamster lung fibroblasts (V79 cells) were exposed to TiO2 NPs at the dose of 0, 5, 10, 20, 50 and 100 μg/mL. Significant decreases in cell viability were detected in all the treated groups after 24 h and 48 h exposure. Significant DNA damage was only observed at the concentration of 100 μg/mL after 24 h treatment using the comet assay. The obvious gene mutation was observed at the concentration of 20 and 100 μg/mL after 2 h treatment using hypoxanthine-guanine phosphoribosyl transferase (HPRT) gene mutation assay. This study presented a comprehensive genotoxic evaluation of TiO2 NPs, and TiO2 NPs were shown to be genotoxic both in vivo and in vitro tests. The gene mutation and DNA strand breaks seem to be more sensitive genetic endpoints for the detection of TiO2 NPs induced genotoxic effects.  相似文献   
54.
Type 2 diabetes (T2D) in the East Asian population is characterized by phenotypes such as low body mass index, an index of β-cell dysfunction, and higher percentage of body fat, an index of insulin resistance. These phenotypes/pathologies may predispose people to early onset of diabetes with increased risk of stroke and renal disease. Less than 50% of patients with T2D in East Asia achieve glycaemic targets recommended by national or regional guidelines, which may be attributable to knowledge and/or implementation gaps. Herein, we review the latest evidence with special reference to East Asian patients with T2D and present arguments for the need to use early combination therapy to intensify glycaemic control. This strategy is supported by the 5-year worldwide VERIFY study, which reported better glycaemic durability in newly diagnosed patients with T2D with a mean HbA1c of 6.9% treated with early combination therapy of vildagliptin plus metformin versus those treated with initial metformin monotherapy followed by addition of vildagliptin only with worsening glycaemic control. This paradigm shift of early intensified treatment is now recommended by the American Diabetes Association and the European Association for the Study of Diabetes. In order to translate these evidence to practice, increased awareness and strengthening of the healthcare system are needed to diagnose and manage patients with T2D early for combination therapy.  相似文献   
55.
目的:评估皮下注射低分子肝素钙对预防烧伤植皮后深静脉血栓(DVT)形成的效果。方法选取2013年1月~2014年12月本院收治的79例烧伤后需植皮的患者,其中皮下注射低分子肝素钙预DVT患者41例设为治疗组。植皮术后仅使用红外线治疗仪照射,硫酸镁热敷,活动肌肉组织等基础措施的38例为对照组。统计血浆D-二聚体(D-dimer)浓度、血小板计数、植皮成活率、创面愈合时间、感染病例数、组织器官出血病例数和DVT形成数等指标。结果治疗组术后第3、7、11、15 d的血浆D-dimer浓度均低于对照组(P<0.05);对照组的血栓形成率为10.5%,明显高于治疗组的0(P<0.05);两组术前1 d的D-dimer浓度、血小板计数,植皮成活率、创面愈合时间、感染及出血发生率差异无统计学意义(P>0.05)。结论皮下注射低分子肝素钙对预防烧伤植皮术后患者DVT形成有一定的临床意义。  相似文献   
56.
Although substantial decreases have been recorded, age-standardized mortality rates from thyroid cancer in Switzerland are still the highest in Europe in men (0.9/100,000), together with those from Austria, and the third highest (1.0/100,000) in women. Detailed analysis of 308 new cases registered between 1974 and 1987 in the Swiss Canton of Vaud revealed an overall incidence rate of 1.36/100,000 men (world standard) in 1974-1980 and of 1.74/100,000 in 1981-1987. Corresponding values for women were 4.28 and 4.51, respectively. Thus, women constituted the majority of all cases (76%). Papillary carcinoma was the most frequent histological type (53%) followed by follicular (27%), undifferentiated (5%) and medullary (2%); other morphologies and clinical tumours accounted for 13% of the whole series. In both sexes, most of the apparent increase over the calendar period was restricted to the papillary type. Overall 5- and 10-year survival rates were 71% and 57%. When various factors were introduced in a Cox proportional-hazard model, young age at diagnosis (hazard rate for greater than or equal to 65 years vs less than 45 = 14.7; 95% confidence interval = 7.5-29.1) and good histological differentiation (hazard rate for papillary and follicular vs undifferentiated = 0.4) emerged as strong favourable and independent prognostic factors. The reduced hazard rate for women, other factors being equal, was of borderline significance (0.7, 95% confidence interval = 0.5-1.0), whereas no significant difference was observed between follicular and papillary carcinomas, and calendar periods of diagnosis.  相似文献   
57.
STING (stimulator of IFN genes) activates the IFN-dependent innate immune response to infection on sensing the presence of DNA in cytosol. The quantity of STING accumulating in cultured cells varies; it is relatively high in some cell lines [e.g., HEp-2, human embryonic lung fibroblasts (HEL), and HeLa] and low in others (e.g., Vero cells). In a preceding publication we reported that STING was stable in four cell lines infected with herpes simplex virus 1 and that it was actively stabilized in at least two cell lines derived from human cancers. In this report we show that STING is exported from HEp-2 cells to Vero cells along with virions, viral mRNAs, microRNAs, and the exosome marker protein CD9. The virions and exosomes copurified. The quantity of STING and CD9 exported from one cell line to another was inoculum-size–dependent and reflected the levels of STING and CD9 accumulating in the cells in which the virus inoculum was made. The export of STING, an innate immune sensor, and of viral mRNAs whose major role may be in silencing viral genes in latently infected neurons, suggests that the virus has evolved mechanisms that curtail rather than foster the spread of infection under certain conditions.The stimulator of IFN genes (STING) is a sensor of cytoplasmic DNA and activates immune responses to intracellular pathogens (13). Knockout of STING exacerbates the pathogenicity of herpes simplex virus (HSV-1) and of other pathogens in mice (2, 3). Two observations reported earlier add to the role of STING in HSV-1 infected cells. Specifically, (i) STING was readily detectable and stable in four different cell lines infected with wild-type virus (4). The stability of STING in cells infected with an HSV-1 mutant lacking the gene encoding ICP0 (infected cell protein no. 0), a key viral regulatory protein, varied. STING was stable in ΔICP0 mutant virus infected cells derived from normal tissues but was rapidly degraded in infected cells derived from human cancers (4). Implicit in this observation is that ICP0 is required to stabilize STING, although STING could also be stabilized in the absence of ICP0 by a cellular function. (ii) Depletion of STING increased wild-type virus yield 10-fold in cells derived from normal tissues but decreased the yield by the same amount in cells derived from human cancer (4). Thus, at least in cells derived from normal tissues, HSV-1 expresses ICP0 that enables the stabilization of STING even though STING is inimical to virus growth. The results of these studies suggest that HSV-1 recruits STING for a specific function, even though the persistence of STING is not beneficial to virus growth, at least in cells derived from normal tissues (4).Here we report that STING, along with viral RNAs contained in structures that coprecipitate with exosome marker proteins, is exported from the cells in which virus is produced to uninfected cells. The quantities introduced into uninfected cells are dose-dependent and reflect the amounts produced in donor cells.Cells continuously secrete a large number of microvesicles, macromolecular complexes, and small molecules into the extracellular space (5, 6). Of the secreted microvesicles, exosomes are 30–120 nm in diameter, containing nucleic acid and proteins, and are perceived to be carriers of this cargo between diverse locations. They are distinguished in their genesis by being budded into endosomes to form multivesicular bodies (MVBs) in the cytoplasm. The exosomes are released to extracellular fluids by fusion of these multivesicular bodies with the cell surface, resulting in secretion (710).Several pathogens use the exosomes to manipulate their microenvironment (11, 12). Viruses, especially small retroviruses such as HIV, use the exosome pathway for egress and immune evasion (1315). The hepatitis C virus uses exosomes for invasion and spread (1618). EBV-infected cells release exosomes containing the latent membrane protein 1 to induce T-cell anergy (1923). In the case of human cytomegalovirus the exosomes carrying viral antigens exacerbate the transplant rejection process (24). It is likely that viruses that establish long-term, latent, or chronic infections modulate exosomes to enhance their persistence (11).Here we report that the exosomes secreted by HSV-1–infected cells deliver to uninfected cells the innate immune sensor STING along with viral RNAs. We speculate that in the long run the strategy serves the virus to fulfill its mission: to spread effectively from person to person.  相似文献   
58.
目的:研究红花-甘草配伍对寒凝血瘀模型大鼠血浆及脑组织中三磷酸腺苷(ATP)、二磷酸腺苷(ADP)、一磷酸腺苷(AMP)及能荷(EC)水平的影响,从能量代谢角度探讨该配伍对寒凝血瘀证的影响。方法:采用冷水冰浴方法成功建立寒凝血瘀证SD大鼠模型,将造模成功大鼠随机分为4组,即模型对照组、红花组、甘草组、红花-甘草组,另设正常对照组。造模成功后,给药组灌胃相应的药物,剂量为20 g·kg-1,模型对照组和正常对照组给予等容积的纯净水,各组均连续灌胃15 d,检测大鼠血浆及脑组织中3种腺苷酸的含量并计算能荷值。结果:与正常对照组相比,模型对照组ATP、ADP的含量及EC值均显著降低(P<0.01),AMP的含量降低不明显。与模型对照组相比,各给药组ATP、ADP的含量及EC值均显著升高,红花-甘草组改善上述指标的作用强于单药组,差异有显著性(P<0.05)。结论:红花和甘草均可改善寒凝血瘀模型大鼠的能量代谢,促进机体对能量物质的利用,红花-甘草配伍对改善寒凝血瘀证能量代谢显示出更佳的疗效。  相似文献   
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60.
BackgroundHepatocellular carcinoma (HCC) is one of the most prevalent malignancies with poor prognosis. There is no research about the clinical significance of serum soluble CD155 (sCD155) level for HCC. We aim to explore the prognostic and diagnostic value of sCD155 in HCC patients undergoing curative resection.MethodsSerum sCD155 level in HCC patients was determined by enzyme‐linked immunosorbent assay. The prognostic significance of sCD155 was evaluated by Cox regression and Kaplan–Meier analyses. CD155 expression and biomarkers of immune cells in HCC tissues were detected by immunohistochemistry staining. The diagnostic significance of sCD155 was evaluated using receiver operating characteristic curve.ResultsSerum sCD155 level was significantly increased in HCC patients and predicted poor prognosis. The prognostic value of sCD155 remained in low recurrent risk subgroups of HCC. Serum sCD155 level was positively related to CD155 expression in HCC tissues. High serum sCD155 level was associated with decreased numbers of CD8+T cells and CD56+NK cells and increased number of CD163+M2 macrophages. Serum sCD155 level had better performance in distinguishing HCC patients from healthy donors and patients with chronic liver conditions than α‐fetoprotein. Among patients with α‐fetoprotein ≤ 20 ng/ml, serum sCD155 level could differentiate HCC patients from non‐HCC patients.ConclusionSerum sCD155 level represents a promising biomarker for diagnosis and prognosis of HCC. High serum sCD155 level may reflect an immunosuppressive tumor microenvironment in HCC.  相似文献   
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