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1.
A series of nonpeptide angiotensin II receptor antagonists was synthesized via palladium-assisted cross coupling of aryl stannane and cycloalkenyl triflates and subsequent alkylation of silyl-protected imidazole. Our compounds, which have a terminal five- to seven-membered cycloalkenyl ring, are compared to DuPont EXP7711, an N-[(2′-carboxybiphenylyl)methyl]imidazole, which has a terminal phenyl moiety. Physicochemical properties of the compounds, such as lipophilicity, steric bulk, conformation, and the relative spatial proximity of the 2-carboxyl and the middle phenyl, are quantitated by computational chemistry. Potency in terms of binding affinity to AT1 receptors in rat adrenal glomerulosa and rabbit aorta is maximized when the terminal ring is aromatic.  相似文献   
2.
A series of 2-alkylbenzimidazole derivatives 9a-n have been designed and synthesized as a novel class of non-peptide angiotensin Ⅱ AT1 receptor antagonists. The synthesized compounds were evaluated for their antagonism of angiotensin Ⅱ, induced contraction in the rabbit thoracic aortic ring and the results showed that compounds 9a, 9g and 9j exhibited potent antagonistic activity of AT1 receptor.  相似文献   
3.
Intact kidney tissue samples of normal and spontaneously hypertensive rats (SHRs) were analyzed by hrMAS-NMR spectroscopy and principal component analysis (PCA). Radial components (cortex, outer stripe of the outer medulla, inner stripe of the outer medulla, and papilla) were sampled from various regions across the kidney from multiple animals in order to establish inter- and intra-animal variability. The effects of temperature were also measured. Papilla was differentiated from the other tissue types, and this variation by tissue type was greater than the effect of temperature on the samples (spectra were compared from samples at 2 and 30 °C). This study also revealed long term stability issues of tissue storage at -80 °C. The PCA showed that the greatest differentiation between normal rats and SHRs was found in the cortex and the regions in the NMR spectra that were correlated with this variation were identified.Abbreviations hrMAS High-resolution magic angle spinning - NMR Nuclear magnetic resonance - PCA Principal component analysis - CSA Chemical shift anisotropy - DD Dipolar coupling - SHR Spontaneously hypertensive rat  相似文献   
4.
以临床典型病案为例,探讨了中医中药传统理论和现代微量元素研究的关系,重点讨论了向量元素锌、宏量元素钙与高血压、风湿症的病因病机和治疗关系。  相似文献   
5.
We describe the procedure developed for the simultaneous detection and quantification of angiotensin II and angiotensin-(1-7), by capillary zone electrophoresis with UV detection by photodiode-array, at a wavelength of 200 nm, in the plasma and urine from hypertensive rats. Optimal separation was achieved with a 100 mM boric acid + 3 mM tartaric acid + 10 fM gold (III) chloride electrolyte solution at pH 9.80. The applied voltage was 30 kV and the capillary temperature was kept constant at 20 °C. The method was over the concentration range of 0.01-500 pmol/mL. All determination coefficients were higher or equal to 0.9985. Limits of detection and quantification for angiotensin II were 0.0110 pmol/mL (S/N = 3) and 0.0195 pmol/mL (S/N = 5), respectively. While for angiotensin-(1-7), the limits were 0.0112 pmol/mL (S/N = 3) and 0.0193 pmol/mL (S/N = 5), respectively. The present method offers a time-saving way to simultaneous determination of angiotensin II and angiotensin-(1-7), since it can be completed in 10 min, compared to other methodologies reported in the literature for capillary electrophoresis and liquid chromatography, which require more than 1 h for analysis of complex matrices, such as plasma and urine. The procedure is illustrated by experiments that quantify simultaneously angiotensin II and angiotensin-(1-7) in plasma and urine from hypertensive and normotensive rats, with and without antihypertensive treatment. The levels of angiotensin II and angiotensin-(1-7) detected in the experimental model, resulted in a recovery of 99.00-106.01% and a reproducibility of less than 10%. The proposed analytical method is a use full tool for the simultaneous detection of angiotensin II and angiotensin-(1-7) implicated in vascular remodeling in pathologies such as hypertension.  相似文献   
6.
高血压病的风险因素分析与研究   总被引:2,自引:1,他引:1  
高血压病是全球性多发病之一,其发病率在中国逐年上升,影响高血压疾病的因素很多,本文研究的是年龄、BMI、家族史、吸烟时间、吸烟数量、饮酒时间、饮酒频率、饮酒数量和户外活动,共九个因素,研究的主要目的是将这些因素对高血压患病影响的重要性程度进行排序,并建立相应患病概率的预测模型,这不仅对医疗保险中保单的核保提供了风险度量的判别依据,而且对于人们日常生活疾病的预防、监视也有一定的指导意义。本文首先用单因子Logistic回归剔除与高血压患病相关性较小的因素,继而用主成分分析方法消除因素的共线性,最后用Logistic回归拟合患病概率模型并根据系数进行排序和预测。结果无论是男性还是女性,对高血压病影响最大的都是家族史,其次为BMI和年龄。  相似文献   
7.
郭小文  陶涛  吕晨  王世萍  马千 《应用数学》2016,38(2):112-116
目的两种不同麻醉和镇痛方法对糖耐量减低的老年患者全膝置换术后糖代谢的影响。方法60例择期行全膝置换术的糖耐量减低患者随机分成腰硬联合麻醉联合术后硬膜外镇痛组(腰硬组)和全身麻醉联合术后静脉镇痛组(全麻组)各30例,分别测定入手术室后,术后30min、1、3、7d的空腹血糖和胰岛素浓度;术后10d空腹和口服糖耐量试验(OGTT)2h的血糖和胰岛素浓度,并计算相应胰岛素抵抗指数,以视觉模糊疼痛评分(VAS)评估术后1h、1、3、7d的疼痛评分,并记录围手术期相关不良事件发生率。结果腰硬组术后30min、1、3d的空腹血糖相比全麻组明显较低(均P<0.05);腰硬组在术后30min、1、3、7d的胰岛素浓度和胰岛素抵抗指数相比全麻组明显较低(均P<0.05)。腰硬组在术后1d和3d的中餐后2h血糖浓度相比全麻组明显较低(均P<0.05)。全麻组术后10d空腹、OGTT2h的胰岛素浓度和胰岛素抵抗指数相比术前均明显升高(均P<0.05),且相比腰硬组明显更高(均P<0.05)。术后1h和术后1d腰硬组VAS评分明显小于全麻组(均P<0.05)。结论腰硬联合麻醉和硬膜外镇痛能减轻糖耐量减低的老年高血压患者的全膝置换术后糖代谢紊乱。  相似文献   
8.
应用原子吸收光谱法检测了老年高血压、冠心病患者血清铁、红细胞内铁及血清铁蛋白、MCH、MCHC。发现老年冠心病患者血清铁、红细胞内铁、血清铁蛋白含量明显高于对照组(P<0.01)。老年高血压患者血清铁蛋白、红细胞内铁、MCH、MCHC也明显高于对照组(P<0.01),血清铁与对照组比较有显著性差异(P<0.05)。结果表明:老年高血压,冠心病患者存在铁代谢异常,其游离铁与储存铁的增加可能是其发病的危险因素之一。  相似文献   
9.
高血压合并冠心病是高血压疾病的一类严重合并症.目前高血压患者对合并冠心病的情况检测不及时,容易导致严重事件的发生,其致残率、致死率极高,严重影响患者的生活质量.因此对高血压患者合并冠心病的早期发现对预防更严重事件的发生显得尤为重要.舌体信息与心血管功能关系密切,为此,提出一种基于舌体高光谱用于高血压患者中合并冠心病筛查...  相似文献   
10.

Background

White matter hyperintensities (WMHs) on MRI have been associated with age, cardiovascular risk factors and falls in the elderly. This study evaluated the relationship between WMHs and dynamics of postural control in older adults without history of falls.

Methods

We studied 76 community-living subjects without history of falls (age 64.5±7.3 years). Brain and WMH volume calculations and clinical rating were done on fluid-attenuation inversion recovery (FLAIR) and MP-RAGE MR images on 3 T. Balance was assessed from the center of pressure displacement using the force platform during 3 min of quiet standing using traditional and dynamic measures (using stabilogram-diffusion analysis). Gait speed was measured from 12-min walk.

Results

Age-adjusted periventricular and focal WMHs were associated with changes in certain dynamic balance measures, including reduced range of postural sway in anteroposterior direction (fronto-temporal WMHs, P=.045; parieto-occipital WMHs, P=.009) and more irregular long-term mediolateral fluctuations (P=.046). Normal walking speed was not affected by WMHs.

Conclusions

Periventricular and focal WMHs affect long-term dynamics of postural control, which requires engagement of feedback mechanisms, and may contribute to mobility decline in the elderly.  相似文献   
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