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991.
This study assessed whether exercising whilst viewing natural or built scenes affected self-esteem (SE) and mood in adolescents. Twenty-five adolescents participated in three exercise tests on consecutive days. A graded exercise test established the work rate equivalent to 50% heart rate reserve for use in subsequent constant load tests (CLTs). Participants undertook two 15-min CLTs in random order viewing scenes of either natural or built environments. Participants completed Rosenberg’s SE scale and the adolescent profile of mood states questionnaire pre- and post-exercise. There was a significant main effect for SE (F(1) = 6.10; P < 0.05) and mood (F(6) = 5.29; P < 0.001) due to exercise, but no effect of viewing different environmental scenes (P > 0.05). Short bouts of moderate physical activity can have a positive impact on SE and mood in adolescents. Future research should incorporate field studies to examine the psychological effects of contact with real environments.  相似文献   
992.
993.
The chitosan-caffeic acid (CCA) conjugate shows a hepatoprotective effect against oxidative stress-induced hepatic damage in cultured hepatocytes. The objective of this study is the verification of the hepatoprotective effect of the CCA in vivo against ethanol-induced liver injury in mice. The administration of ethanol resulted in the increase of the serum-aminotransferase activities (AST and ALT), triglycerides, total cholesterol, and lipid peroxidation. The CCA co-administration, however, significantly (p < 0.05) ameliorated these serum biomarkers. The antioxidant-enzyme activities in the liver tissue, including those of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), were significantly decreased by a chronic ethanol administration, whereas the hepatic lipid-peroxidation level was increased. Moreover, the chronic ethanol administration elevated the gene expression of pro-inflammatory cytokines such as tumor-necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the liver tissue. The CCA co-administration, however, significantly (p < 0.05) increased the activities of the SOD, CAT, and GPx and caused the down-regulation of the TNF-α- and IL-6-gene expressions in the liver tissue. An histopathologic evaluation also supported the hepatoprotective effect of the CCA against ethanol-induced hepatotoxicity in the mice.  相似文献   
994.
995.
This publication describes the history of minimal intervention dentistry (MID) for managing dental caries and presents evidence for various carious lesion detection devices, for preventive measures, for restorative and non‐restorative therapies as well as for repairing rather than replacing defective restorations. It is a follow‐up to the FDI World Dental Federation publication on MID, of 2000. The dental profession currently is faced with an enormous task of how to manage the high burden of consequences of the caries process amongst the world population. If it is to manage carious lesion development and its progression, it should move away from the ‘surgical’ care approach and fully embrace the MID approach. The chance for MID to be successful is thought to be increased tremendously if dental caries is not considered an infectious but instead a behavioural disease with a bacterial component. Controlling the two main carious lesion development related behaviours, i.e. intake and frequency of fermentable sugars, to not more than five times daily and removing/disturbing dental plaque from all tooth surfaces using an effective fluoridated toothpaste twice daily, are the ingredients for reducing the burden of dental caries in many communities in the world. FDI's policy of reducing the need for restorative therapy by placing an even greater emphasis on caries prevention than is currently done, is therefore, worth pursuing.  相似文献   
996.
An inevitable loss of soft and hard tissue after tooth extraction often results in a compromised site for anterior implant esthetics in both vertical and horizontal dimensions. Immediate implant placement and provisionalization has been a viable option for replacing failing maxillary anterior teeth as it preserves the vertical existing osseous and gingival architecture. With the simultaneous addition of soft‐ and hard‐tissue grafts, the peri‐implant horizontal tissue topography can also be maintained. The esthetic success of immediate implant placement and provisionalization procedures is influenced by a number of factors that can be identified as patient‐dependent or clinician‐dependent. This article describes in detail the process of patient selection, indications, contraindications, diagnosis, treatment planning and treatment execution required to achieve functional and esthetic success with immediate implant placement and provisionalization.  相似文献   
997.
Several studies have suggested that rheumatoid arthritis (RA) is uncommon in rural sub-Saharan Africa. The aim of this study is to determine the potential differences between patients with RA living in rural areas and those living in urban areas. We performed a cross-sectional study from June 2006 to May 2009. We included all patients with RA (1987 ACR criteria) seen at the Rheumatology Unit of the Le Dantec Teaching Hospital, Dakar, Senegal. We compared the main socio-demographic and clinical characteristics of patients living in rural areas to those living in urban areas. We included 180 patients in our study, of whom, 143 (79.4?%) lived in urban areas and 37 (20.6?%) in rural areas. The median age was 44?years [range 34–55] in patients from rural areas vs. 41?years [range 30–53] in patients from urban areas, without any statistical significance (p?=?0.24). Patients under the age of 60 mostly lived in urban areas (p?=?0.03). The extra-articular manifestations were significantly more frequent in patients living in rural areas (p?=?0.02). There was no statistical significance when comparing the delay in diagnosis, number of swollen joints, disease activity, hand deformities, and concentration of autoantibodies (RF and ACPA) in both populations. The percentage of patients seen from the rural areas of Senegal is low (20.6?%) compared to those seen from the urban areas. The number of extra-articular manifestations is the main difference between patients living in rural and urban areas. The role played by environmental factors seems important. Further incidence studies are needed.  相似文献   
998.
999.
1000.
目的初步建立口服苯丙氨酸负荷实验筛选苯丙酮尿症(PKU)杂合子的方法。方法采用病例对照研究,观察4例PKU杂合子(为已确诊PKU患儿的父母)和4例年龄、性别、体质量与前者相匹配的健康对照者,空腹、口服苯丙氨酸后1、2、3、4、6、24 h,血清苯丙氨酸(Phe)、酪氨酸(Tyr)浓度及其比值(Phe/Tyr)的变化。血清Phe、Tyr浓度采用高效液相色谱仪测定。结果口服Phe 2 h,PKU杂合子与对照者的Phe/Tyr均达到峰值,两者间血清Phe浓度和Phe/Tyr呈现显著差异(P<0.05);且两者之间的数值范围无重叠,其中Phe/Tyr的差距更大。结论口服苯丙氨酸负荷实验有助于筛选人群中的PKU杂合子。  相似文献   
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