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91.
CsStefin-2, the second cysteine protease inhibitor of Clonorchis sinensis, was identified and characterized. CsStefin-2 is a cysteine protease inhibitor that belongs to family 1 stefins based on its phylogenetic and structural properties. However, CsStefin-2 had a QIVSG cystatin motif distinct from the common QVVAG cystatin motif that is well conserved in family 1 stefins. Mutagenesis analysis revealed that the two amino acid substitutions in the QIVSG cystatin motif of CsStefin-2 did not affect its inhibitory activity. Molecular modeling also indicated that no critical change was induced in the interaction between CsStefin-2 and its target enzyme. CsStefin-2 showed broad inhibitory activities against several cysteine proteases, including human cathepsins B and L, papain, and cathepsin Fs of C. sinensis (CsCFs), and effectively inhibited the autocatalytic maturation of CsCF-6. Native CsStefin-2 was assembled into a homo-tetramer, in which intermolecular disulfide bonds are not involved in the assembly of the tetramer. CsStefin-2 was expressed throughout the various developmental stages of the parasite and was localized in the intestinal epithelium, where CsCFs are actively synthesized. These results suggest that CsStefin-2 is the second active cysteine protease inhibitor of C. sinensis that shares functional redundancy with CsStefin-1 to modulate the activity and processing of CsCFs.  相似文献   
92.

Objectives

To evaluate the effectiveness of natural compounds containing mouthrinse (NCCM) as an adjunct to unsupervised oral hygiene in the management of dental plaque and gingivitis.

Materials and methods

An electronic search for clinical studies of NCCMs was conducted in Medline-PubMed, the Cochrane Central Register of Controlled Trials and EMBASE for a period spanning from the earliest available date in each database up to February 2013. Plaque index, gingival index, and gingival bleeding index were selected as primary outcomes. The methodological quality of the studies was assessed according to the “Levels of Evidence” outlined by the Center of Evidence-Based Medicine, and to the Jadad scale.

Results

The screen yielded 2,236 titles and abstracts that met the inclusion criteria. These identified 11 clinical trials testing 13 different NCCMs, and were used for data extraction. Heterogeneity and the limited number of studies on any individual NCCM precluded a formal meta-analysis. Of the 13 NCCMs tested, eight demonstrated positive results, and few reported any adverse effects or events.

Conclusions

Evidence proving the effectiveness of NCCM as an adjunct to unsupervised oral hygiene for plaque and gingivitis control is still insufficient. However, some natural products (compounds) may have oral health benefits, so further high-quality study is warranted.

Clinical relevance

This review provides an overview of the strength of clinical evidence regarding the effectiveness of natural compounds containing mouthrinses in promoting gingival health.  相似文献   
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朝藿甙A的结构   总被引:4,自引:0,他引:4  
从朝鲜淫羊藿(Epimedium koreanum Nakai)地上部分分离得到一个新黄酮醇甙类成分:朝藿甙A(ChaohuosideA,I),经光谱分析证明,其结构为7-O-β-D-吡喃葡萄糖-脱水淫羊藿素-3-O-β-D-(3,6-O-二乙酰基)-吡喃葡萄糖-(1→3)-α-L-(4-O-乙酰基)-吡喃鼠李糖甙。  相似文献   
97.
目的 用电 解剖标测方法标测右心房 ,然后比较心房扑动 (AFL)和房室结折返性心动过速(AVNRT)患者在下腔静脉 三尖瓣环峡部 (CTI)和心房间隔部 (AS)的电冲动传导速度 ,以便确定AFL患者除了解剖结构上的异常外 ,是否伴有心房电生理方面的异常变化。方法  1 0例AFL患者 ,男性 7例 ,女性 3例 ,平均 (53± 1 0 )岁 ;1 3例AVNRT患者 ,男性 5例 ,女性 8例 ,平均 (51± 1 1 )岁。对这两组患者进行了详细的电 解剖标测、电生理检查和射频消融术。分别以周长为 60 0、40 0、和 30 0ms在冠状静脉窦 (CS)起搏的情况下测量AFL和AVNRT患者的CTI和AS的冲动传导速度 ,并将两组患者在CTI和AS的冲动传导速度进行比较。结果 与AVNRT患者相比 ,AFL患者在各个起搏周长 (PCL)时CTI和AS的冲动传导速度都明显减慢 (P <0 0 5)。另外 ,在AFL组 ,AS的冲动传导速度在起搏周长 60 0、40 0ms时低于CTI,但在 30 0ms时差异无显著性 (P >0 0 5)。因为在AFL组 ,PCL为 30 0ms时的冲动传导速度明显低于 60 0和 40 0ms时的冲动传导速度 ,致使PCL为 30 0ms时CTI和AS的冲动传导速度差异无显著性。结论 与CTI相比 ,AS的冲动传导速度在所有患者都较慢 ,而AFL患者在CTI和AS的冲动传导速度减低更明显 ,并且在CTI的冲动传导速度减慢具有频率依  相似文献   
98.
Bony inlet stenosis as a cause of nasal airway obstruction   总被引:2,自引:0,他引:2  
Ey  EH; Han  BK; Towbin  RB; Jaun  WK 《Radiology》1988,168(2):477-479
Two cases of congenital bony stenosis of the nasal piriform aperture (anterior nares) are presented. Both patients experienced episodes of respiratory distress and clinical symptoms similar to those seen in patients with posterior choanal atresia. The underlying anatomic abnormalities in congenital bony inlet stenosis are quite different from those in choanal atresia and require different surgical approaches for correction. Computed tomography demonstrates in detail the underlying anatomic abnormality and allows differentiation of bony inlet stenosis from choanal atresia.  相似文献   
99.
Asthma is the most common chronic pulmonary disease worldwide and places a considerable economic burden on society. China is the world''s largest developing country and has the largest population. China has undergone dramatic changes in the past few decades. The traditional lifestyle and living environment have changed in ways that directly affect the prevalence of asthma. The prevalence of asthma is lower in Chinese children and adults than in developed countries, but the prevalence has been on the rise during the past 30 years. The prevalence significantly varies among different parts of China. Polymorphisms of multiple genes, outdoor air pollution caused by PM2.5, PM10, SO2, NO2, environmental tobacco smoke, and coal, indoor pollution, and inhaled allergens, such as house dust mites, pollen, and cockroach particles, are risk factors for asthma.  相似文献   
100.
This article provides a general framework for understanding the use of information and communication technology in education and discusses the impact of computer usage on students' health and development. Potential beneficial and harmful effects of computer use by children are discussed. Early epidemiological and laboratory studies have indicated that children are at least of similar risk of developing musculoskeletal and vision problems as adults, and musculoskeletal and visual health problems developed in childhood are likely to persist into adulthood. This article, therefore, aims to provide a reflection on the deficits of existing policy and recommendations for child‐specific guidelines in computer use.  相似文献   
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