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71.
丁香水溶性化学成分的研究 总被引:2,自引:0,他引:2
目的:研究丁香水溶性化学成分。方法:利用HP-20大孔吸附树脂、反相硅胶柱色谱、反相制备薄层色谱、制备型反相高效液相色谱进行分离,NMR和MS等方法进行结构鉴定。结果:从丁香干燥花蕾的水提物中分离鉴定了5个化合物,分别为槲皮素-3-O-葡萄糖醛酸苷(1),槲皮素-3-O-葡萄糖醛酸苷6″-甲酯(2),槲皮素-3-O-葡萄糖苷(3),丁香酚-β-芸香糖苷(4),杨梅酮(5)。结论:化合物1~4为首次从丁香属植物中分离得到。 相似文献
72.
OBJECTIVE: To prospectively document the prevalence of otitis media with effusion (OME) in 86 African-American children between ages 2 and 5 years. STUDY DESIGN: Eighty-six children in center-based child care whose ear status had been followed from infancy continued to be observed. Middle ear status was assessed by pneumatic otoscopy and tympanometry biweekly. RESULTS: The prevalence of OME decreased as children became older. The mean proportion of examinations demonstrating bilateral OME (BOME) ranged from 12% between 24 to 30 months to 4% between 54 to 60 months of age. The mean proportion of exams revealing bilateral normal ears increased from 77% at 24 to 30 months to 88% at 54 to 60 months of age. Although 60 children had experienced BOME that lasted 4 months or longer in the 6- to 24-month age period, only 8 of these children experienced at least 4 months of continuous BOME between 24 to 60 months. CONCLUSIONS: The proportion of time with BOME decreased progressively with increasing age in this population. Only 8 of 60 children who had experienced more than 4 consecutive months of BOME before 2 years of age continued to manifest persistent effusion or experience recurrences of prolonged BOME after 2 years of age. 相似文献
73.
3-Hydroxysteroid-dehydrogenase (3-HSD) is an isoenzyme that catalyses an essential step in the synthesis of all classes of active steroid hormones. The presence of steroid hormones of the vertebrate type in invertebrates is acknowledged in addition to a group of steroid-like hormones called ecdysteroids that were present in arthropods and helminths. In the present study, 3-HSD was detected in the bradyzoites enclosed in sarcocysts of Sarcocystis spp. with immunohistochemistry. The results suggest that self-originating steroid hormones may play important roles in the development of Sarcocystis spp., and possibly in the regulation of the reciprocal immune interaction between the host and these parasites. 相似文献
74.
Abd El Kader NM Blanco MA Ali-Tammam M Abd El Ghaffar Ael R Osman A El Sheikh N Rubio JM de Fuentes I 《Parasitology research》2012,110(1):161-166
Cryptosporidium is a significant cause of diarrheal disease in developing and industrialized nations. Cryptosporidium hominis and Cryptosporidium parvum are the main agents of cryptosporidiosis in humans. In Egypt, very little is known about genetic structure of Cryptosporidium spp. Therefore, this study was designed to examine samples from sporadic cases of cryptosporidiosis in Egyptians in order
to identify the species involved in infection as well as the transmission dynamics and distribution of the parasite in the
Great Cairo area. A total of 391 human faecal samples were collected, between May 2008 and March 2009, from ten public hospitals
in Great Cairo. Initial screening by immunochromatographic detection kit “the Stick Crypto-Giardia; Operon” showed 23 possible
positive cases. Twenty of them were confirmed by microscopic examination. PCR was performed by amplification of the oocyst
wall protein (COWP) gene where 18 out of 23 samples were positive, one not detected by microscopy. Cryptosporidium genotyping was performed by RFLP analysis of PCR products of the diagnosis PCR. Only 15 samples rendered a digestion pattern.
The genotyping distribution was nine cases showing C. hominis genotype, three showing C. parvum genotype and three showing mixed infection by C. hominis and C. parvum. The data showed an elevated prevalence of C. hominis (80.0%), the most anthroponotic species, suggesting a human–human transmission. Furthermore, the presence of up to 40% of
samples infected with C. parvum shows that further investigations are required to determine the subgenotypes of C. parvum to clarify the mode of transmission in order to improve the control measures. 相似文献
75.
Relationship between hours of CPAP use and achieving normal levels of sleepiness and daily functioning 总被引:8,自引:0,他引:8
Weaver TE Maislin G Dinges DF Bloxham T George CF Greenberg H Kader G Mahowald M Younger J Pack AI 《Sleep》2007,30(6):711-719
STUDY OBJECTIVES: Evidence suggests that, to maintain treatment effects, nasal continuous positive airway pressure (CPAP) therapy for obstructive sleep apnea (OSA) needs to be used every night. What remains unknown is the nightly duration of use required to normalize functioning. This study, employing probit analyses and piecewise regression to estimate dose-response functions, estimated likelihoods of return to normal levels of sleepiness and daily functioning relative to nightly duration of CPAP. DESIGN: Multicenter, quasi-experimental study. SETTING: Seven sleep centers in the United States and Canada. PARTICIPANTS: Patients with severe OSA (total cohort n = 149; the numbers of included participants from 85 - 120, depending on outcome analyzed.) Interventions: CPAP. MEASUREMENTS AND RESULTS: Before treatment and again after 3 months of therapy, participants completed a day of testing that included measures of objective and subjective daytime sleepiness and functional status. There were significant differences in mean nightly CPAP duration between treatment responders and nonresponders across outcomes. Thresholds above which further improvements were less likely relative to nightly duration of CPAP were identified for Epworth Sleepiness Scale score (4 hours), Multiple Sleep Latency Test (6 hours), and Functional Outcomes associated with Sleepiness Questionnaire (7.5 hours). A linear dose-response relationship (P < 0.01) between increased use and achieving normal levels was shown for objective and subjective daytime sleepiness, but only up to 7 hours use for functional status. CONCLUSIONS: Our analyses suggest that a greater percentage of patients will achieve normal functioning with longer nightly CPAP durations, but what constitutes adequate use varies between different outcomes. 相似文献
76.
Mechanisms of H2O2-induced oxidative stress in endothelial cells exposed to physiologic shear stress
Coyle CH Kader KN 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2007,53(1):17-22
Hydrogen peroxide (H2O2) is produced by inflammatory and vascular cells and induces oxidative stress, which may contribute to vascular disease and endothelial cell dysfunction. In smooth muscle cells, H2O2 induces production of O2 by activating NADPH oxidase. However, the mechanisms whereby H2O2 induces oxidative stress in endothelial cells are not well understood, although O2 may play a role. Recent studies have documented increased O2 in endothelial cells exposed to H2O2 via uncoupled nitric oxide synthase (NOS) and NADPH oxidase under static conditions. To assess responses to H2O2 in porcine aortic endothelial cells (PAEC) under shearing conditions, a constant flow rate of 24. 4 ml/min was applied to produce physiologically relevant shear stress (8. 2 dynes/cm). Here we demonstrate that treatment with 100 muM H2O2 increases intracellular O2 levels in PAEC. In addition, we demonstrate that l-NAME, an inhibitor of NOS, and apocynin, an inhibitor of NADPH oxidase, reduced O2 levels in PAEC treated with H2O2 under physiologic shear suggesting that both NOS and NADPH oxidase contribute to H2O2-induced O2 in PAEC. Co-inhibition of NOS and NADPH oxidase also reduced intracellular O2 levels under shear. We conclude that H2O2-induced oxidative stress in endothelial cells exhibits increased intracellular O2 levels through NOS and NADPH oxidase under shear. The inhibition of NOS and NADPH with H2O2 exposure is nonlinear, suggesting some interdependent or compensating system within endothelial cells. These findings suggest a complex interaction between H2O2 and oxidant-generating enzymes that may contribute to endothelial dysfunction in cardiovascular diseases. 相似文献
77.
Targeted vessel reconstruction in non‐contrast‐enhanced steady‐state free precession angiography 下载免费PDF全文
Efe Ilicak Suheyla Cetin Elif Bulut Kader Karli Oguz Emine Ulku Saritas Gozde Unal Tolga Çukur 《NMR in biomedicine》2016,29(5):532-544
Image quality in non‐contrast‐enhanced (NCE) angiograms is often limited by scan time constraints. An effective solution is to undersample angiographic acquisitions and to recover vessel images with penalized reconstructions. However, conventional methods leverage penalty terms with uniform spatial weighting, which typically yield insufficient suppression of aliasing interference and suboptimal blood/background contrast. Here we propose a two‐stage strategy where a tractographic segmentation is employed to auto‐extract vasculature maps from undersampled data. These maps are then used to incur spatially adaptive sparsity penalties on vascular and background regions. In vivo steady‐state free precession angiograms were acquired in the hand, lower leg and foot. Compared with regular non‐adaptive compressed sensing (CS) reconstructions (CSlow), the proposed strategy improves blood/background contrast by 71.3 ± 28.9% in the hand (mean ± s.d. across acceleration factors 1–8), 30.6 ± 11.3% in the lower leg and 28.1 ± 7.0% in the foot (signed‐rank test, P < 0.05 at each acceleration). The proposed targeted reconstruction can relax trade‐offs between image contrast, resolution and scan efficiency without compromising vessel depiction. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
78.
目的探讨暴恐突发事件救治中有效预防与控制医院感染的措施,分析暴恐突发事件成批爆炸伤伤员医院感染的特征。
方法选取新疆维吾尔自治区人民医院收治的19名爆炸伤伤员作为研究对象,在执行日常感染控制措施的基础上结合突发公共卫生事件发生的特点,落实人员物品管理、环境清洁与消毒、筛查医院获得性肺炎等有效的医院感染防控措施,分析伤员的抗菌药物使用情况、微生物标本送检情况以及伤员的医院感染率。
结果存在年龄60岁以上居多、全身多发性损伤、合并有基础疾病等多种医院感染危险因素,易发生医院感染;19名伤员经医疗救治后全部临床治愈出院,平均住院时间为(50.8±58.2)d,医院感染发病率为31.6%,以下呼吸道感染为主,占62.5%。抗菌药物使用率为63.2%(12/19);微生物送检率为100%(12/12)。
结论突发事件伤员救治需及时分析伤员感染特点,完善并严格落实医院感染防控措施,以降低医院感染发生。 相似文献
79.
目的 研究腹针治疗周围性面瘫的选穴规律。方法 通过计算机及手工检索,选取近15年有关腹针治疗周围性面瘫的相关文献,以临床研究、疗效观察、现代对比实验研究为依据,进行分析归纳,探讨腹针的选穴规律。结果 腹针治疗周围性面瘫主要取任脉、肾经、胃经及脾经上的穴位及腹部新穴,使用频率依次为55.70%、15.44%、14.09%、2.68%、12.08%;腹针治疗周围性面瘫选用的标志性穴位组合规律:主要有引气归元、腹四关、天地针、调脾气,其使用频率依次为48.48%、27.27%、12.12%、12.12%。结论 合理运用腹针,遵循其选穴规律,可有效治疗周围性面瘫。 相似文献
80.
P Karagianni SA Polyzos N Kartali I Zografou C Sambanis 《Advances in medical sciences》2013,58(1):38-43
PurposeComparative efficacy of exenatide versus insulin glargine primarily on glucemic control, and secondarily on body mass index (BMI), lipid profile and blood pressure, in type 2 diabetes mellitus (T2DM) patients suboptimally treated with metformin monotherapy.Material/MethodsForty-seven inadequately treated T2DM patients on metformin assigned to exenatide (n=18) or insulin glargine (n=29) for 26 weeks. Glycosylated hemoglobin (HbA1c), serum lipids, BMI, systolic and diastolic blood pressure, and adverse events, including episodes of hypoglycemia and gastrointestinal symptoms, were recorded.ResultsEither treatment had a similar favorable mean reduction in HbA1c. However, more patients in exenatide group achieved HbA1c ≤ 7% at the 26th week compared with insulin glargine group (p=0.036). Insulin glargine group had significantly more episodes of hypoglycemia compared with exenatide group (p=0.039). Gastrointestinal adverse events were non-significantly higher in the exenatide group. A significantly greater BMI reduction was observed in exenatide group, whereas BMI was not altered in insulin glargine group. Total and LDL cholesterol (p=0.012), and triglycerides (p=0.016) significantly decreased, whereas HDL cholesterol increased (p=0.021) in the exenatide group, whereas only total cholesterol decreased in insulin glargine group. Changes in systolic and diastolic blood pressure were insignificant in both groups.ConclusionsExenatide provided similar reduction in HbA1c, but fewer episodes of hypoglycemia, compared with insulin glargine. Exenatide had also a favorable effect on weight loss, although more gastrointestinal adverse events. Exenatide may provide a justified alternative in second line treatment of T2DM, but more trials are required to elucidate its long-term safety and cost-effectiveness. 相似文献