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排序方式: 共有622条查询结果,搜索用时 15 毫秒
31.
目的:建立以高效液相色谱法测定小儿磨积片中橙皮苷含量的方法。方法:色谱柱为SpherisorbC18,流动相为甲醇-冰醋酸-水(25∶4∶71),检测波长为283nm,流速为2·0ml/min,柱温为50℃,灵敏度为0·16AUFS,进样量为20μl。结果:橙皮苷进样量在0·024μg~1·2μg范围内与峰面积积分值呈良好的线性关系(r=0·9999),平均回收率为99·1%(RSD=0·8%)。结论:本方法简便、快捷,灵敏度及准确度高,可为小儿磨积片质量控制提供依据。 相似文献
32.
摘要:目的 探讨新疆乌鲁木齐市维吾尔族人群成人支气管哮喘的影响因素。方法 本研究采用成组匹配病例对照研究方法,病例组为新疆医科大学第一附属医院呼吸内科在2014年1-12月确诊的维吾尔族支气管哮喘成人患者(n=120例),对照组为同期体检中心健康维吾尔族体检者(n=126例),两组在年龄、性别相匹配。采用问卷调查的方法收集相关暴露资料,并采用单因素分析及多因素非条件Logistic回归模型分析成人支气管哮喘影响因素。结果 多因素Logistic回归分析显示,吸烟(OR=1.88,95% CI:1.28~2.96)、家族支气管哮喘史(OR=6.20,95% CI:2.10~18.31)、家中铺有纯毛地毯数量多(OR=1.87,95% CI:1.18~2.95),睡眠质量(OR=1.46,95% CI:1.22~1.75),患慢性支气管炎(OR=13.43,95% CI:6.65~25.34)及过敏性鼻炎(OR=6.27,95% CI:3.63~10.81)是维吾尔族成人支气管哮喘的主要影响因素。结论 维吾尔族成人支气管哮喘是生活方式、环境及遗传等多种因素共同作用的结果,应加强对相关影响因素的预防及治疗,减少哮喘的发生,改善哮喘患者生活质量。 相似文献
33.
Abstract – The occurrence of supra- and subgingival calculus, gingival inflammation, periodontal pockets ( 5 mm) and alveolar bone loss was determined in children (10-19 yr) with Down's syndrome (D-S) and in an aged- and sex-matched control group ( n = 39). Of D-S children ( n = 71), 39 of the patients (mean age 15.5 yr) cooperated in a clinical and roentgenologic examination. Alveolar bone loss was determined around incisors and first molars on intraoral radiographs when the distance between cementoenamel junction (GEJ) to alveolar crest (AC) exceeded 2.0 mm. Alveolar bone loss was diagnosed in 39% of the D-S children compared to 3% in the control group ( P <0.001). Of the total number of sites examined on radiographs the distance from CEJ to AC exceeded 2.0 mm in 8% in the D-S group compared to 0.2% in the control group ( P <0.001). The frequency of sites with alveolar bone loss in D-S children was significantly ( P <0.001) higher around the mandibular incisors compared to first molars. The study shows that early signs of periodontitis are frequently seen in D-S children as early as 11 yr of age and the lesions are first diagnosed in the mandibular anterior region. 相似文献
34.
L Bernstein C Chilvers T Murrells M C Pike 《Journal of epidemiology and community health》1986,40(3):214-217
A recent paper has suggested that there is a temporal cycle in birth rates of men with testis cancer with a peak in April/May. We have investigated the suggestion using data from the South Thames and Los Angeles cancer registries. There is some slight evidence of a peak in August, which is confined to teratomas. The effects demonstrated are, however, too small and inconsistent to provide any real clue to the aetiology of testis cancer. 相似文献
35.
Myocardial tagging in polar coordinates with use of striped tags 总被引:1,自引:0,他引:1
Regional deformation abnormalities in the heart wall provide a good indicator of ischemia. Myocardial tagging with magnetic resonance imaging is a new method of assessing heart wall motion during contraction. Current methods of myocardial tagging either do not provide two-dimensional information or lack a coordinate system well adapted to the morphology of the heart. In this article, the authors describe a new tagging method that provides a true polar coordinate system, with both radial and angular dimensions. This is accomplished with use of a section-selective version of spatially modulated magnetization resulting in striped tags (STAGs). These STAG planes are placed in the myocardium in a star pattern so that they intersect on the long axis of the heart and stripes appear through the width of the heart wall. In the short-axis view during contraction, rotation around the long axis yields angular information such as shear and twist, while separation of the stripes within the myocardium permits measurement of radial thickening. Therefore, this method provides a coordinate system for calculating two-dimensional strain that is adapted to the morphology of the left ventricle. 相似文献
36.
Hazel A Jones Karen A Cadwallader Jessica F White Mohib Uddin A Michael Peters Edwin R Chilvers 《Journal of nuclear medicine》2002,43(5):652-657
Neutrophil granulocytes play a key role in the pathogenesis of a wide variety of pulmonary diseases. In many such conditions, the injury observed reflects the activation status rather than the total number of inflammatory cells present. The metabolic activity of neutrophils can now be assessed noninvasively using PET to measure the regional uptake of (18)F-FDG after intravenous injection. METHODS: To understand the mechanism responsible for the increased (18)F-FDG signal, we have measured the uptake of tritiated deoxyglucose (DG) in neutrophils isolated from human peripheral blood and sought to determine which aspects of neutrophil function correlate with an increase in DG uptake. RESULTS: Our results show that formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated respiratory burst activity and (3)H-DG uptake are temporally dissociated, that neutrophil-priming agents such as tumor necrosis factor-alpha (TNFalpha) cause an identical increase in (3)H-DG uptake compared with fMLP without affecting respiratory burst activity, and that fMLP stimulation of TNFalpha-primed cells causes major upregulation of superoxide anion generation (O(2)(-)) yet no incremental increase in (3)H-DG uptake. Furthermore, direct activation of reduced nicotinamide adenine dinucleotide phosphate oxidase activity with the ester phorbol 12-myristate 13-acetate resulted in a concentration-dependent loss of cell-associated (3)H-DG, and preincubation of neutrophils with the phosphoinositide 3-kinase inhibitor wortmannin, which abolished both agonist-stimulated superoxide anion generation and degranulation, had no effect on TNFalpha- or fMLP-stimulated (3)H-DG uptake. In contrast, the fMLP-stimulated change in neutrophil shape was not influenced by priming or wortmannin, and of the functional responses examined, this appeared to correlate most closely with (3)H-DG uptake. CONCLUSION: DG uptake occurs in both primed and activated neutrophils. It does not correlate with respiratory burst or secretory activity but may reflect the polarization and migrational status of these cells. These data have important implications for the analysis of (18)F-FDG signals in vivo. 相似文献
37.
38.
JD Fernandes† MC de Lorenzo Messina† ER de Almeida Pimentel† LGM Castro†‡§ 《Journal of the European Academy of Dermatology and Venereology》2008,22(6):704-706
In order to quantify presence of residual BCC in patients with histologic positive margins after the first excison and to correlate the presence of residual tumor in re‐excised lesions with the location of the positive margin on the first excision, a retrospective evaluation of 2053 surgically treated BCC was performed. Only 38.3% of the re‐excised lesions showed residual tumor. In the group of re‐excised lesions where residual BCC was found, 13% had lateral positive margin in the first excision, 39% had deep positive margin and 48% had both lateral and deep positive margins. In the group of re‐excised lesions where no residual BCC was found, 49% of the primary excised lesions had lateral positive margin, 32% had deep positive margin and 19% had both deep and lateral positive margins. The association between residual tumor and positive margins was statistically significant (p = 0.01). Our findings confirm that presence of residual tumour is more likely when both lateral and deep margins are compromised. 相似文献
39.
40.
KARIN BJERKEBORN GÖRAN DAHLLOF GUNILLA HEDLIN MARGARET LINDELL THOMAS MODÉER 《European journal of oral sciences》1987,95(2):159-164
Abstract – Oral health was studied in a group of asthmatic children (n = 61). The children were divided in two groups, 5–10 and 11–18 yr of age. The individuals with asthma were further sub grouped with respect to the disease severity. Severe asthma was defined as more than 10 asthmatic attacks per year. This patient group had daily medication compared to children with moderate asthma (<10 asthmatic attacks/yr) who medicated temporarily. 55 age matched children from the same area made up the control group. Ail children were examined clinically and two bitewing radiographs were taken. The results showed no statistically significant differences concerning caries prevalence and gingival condition in asthmatic children compared to a healthy control group. The study shows that neither the asthma per se nor the disease severity affected the caries prevalence and gingival condition in asthmatic children. 相似文献