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排序方式: 共有193条查询结果,搜索用时 15 毫秒
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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   
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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   
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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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目的:观察染料木黄酮对成骨细胞活性的影响及其相关机制。方法:实验于2001-05/2003-05在卫生学环境医学研究所实验室完成。①成骨细胞培养:无菌条件下分离出生3d的乳鼠颅盖骨,剪碎,加入胰蛋白酶和Ⅱ型胶原酶,用含体积分数为0.1的胎牛血清的F-12培养基重悬,调整细胞浓度后接种于25mL细胞培养瓶,Ⅱ代细胞用于实验。②实验方法:实验分为染料木黄酮组、雌激素组和对照组(吐温20),染料木黄酮剂量分别为10-5,10-6、10-7mol/L,雌激素剂量分别为10-9,10-10mol/L,培养48,72h后,应用MTT和3H-TdR掺入实验观察不同剂量的染料木黄酮和雌激素对成骨细胞活性影响,免疫组化的方法测定白细胞介素6表达。结果:①A570nm值:培养48h,染料木黄酮10-5,10-6,10-7mol/L组分别比对照组增加105%,136%和143%;10-9,10-10mol/L雌激素组分别比对照组增加84%和100%;培养72h,染料木黄酮3个剂量组分别比对照组增加93%,113%和146%,各剂量组与对照组相比均有显著性差异(P<0.05)。②3H-TdR掺入量:10-5,10-6,10-7mol/L染料木黄酮组分别比对照组增加0.47,11.29,6.45倍;10-9和10-10mol/L雌激素组增加15.4倍和16.5倍(P<0.05)。③白细胞介素6表达:各组成骨细胞周围均有较强的呈棕色的阳性颗粒,但染料木黄酮组组与对照组相比无明显差别。结论:①10-5~10-7mol/L染料木黄酮和雌激素一样可促进成骨细胞增殖和DNA合成。②染料木黄酮不是通过促进白细胞介素6表达来促进成骨细胞增殖与分化。  相似文献   
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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   
70.
We evaluated whether the presence of polycystic ovaries in adolescent girls as a cause of oligomenorrhoea and amenorrhoea would pose any protective effect against osteoporosis or low bone mineral density (BMD) compared with girls having similar menstrual dysfunction but normal ovaries. A cross-sectional observational study was done in consecutive girls, aged between 16 and 19 years, presenting to the adolescent gynaecology clinic with oligomenorrhoea or amenorrhoea. All patients underwent full hormonal profile assessment, pelvic ultrasound for ovarian morphology, bio-impedance estimation of body fat, and dual-energy X-ray absorptiometry and quantitative peripheral computed tomography scans to determine BMD in axial and appendicular skeletal sites. Polycystic ovaries were diagnosed according to ultrasound morphology. These were then compared with an age-matched eumenorrhoeic control group that had undergone the same evaluation. Of 45 patients with oligomenorrhoea or amenorrhoea, 14 (31%) were diagnosed to have polycystic ovaries, while the other 31 had normal ovaries. The control group consisted of 45 age-matched eumenorrhoeic girls. The group with normal ovaries had lower BMD at the lumbar spine and hip, as well as lower total tibial volumetric BMD, than the eumenorrhoeic controls, but there were no significant differences between the group with polycystic ovaries and eumenorrhoeic controls. We conclude that adolescents with oligomenorrhoea and amenorrhoea with normal ovaries had lower BMD than eumenorrhoeic ones, but those with polycystic ovaries had BMD values comparable to those of eumenorrhoeic controls despite their menstrual dysfunction.  相似文献   
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