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71.
中药地龙中溶栓成分研究进展 总被引:7,自引:1,他引:7
对近年来国内外地龙中溶栓成分(蚓纤溶酶、蚓激酶、蚓胶原酶)的研究情况进行归纳,介绍了地龙中溶栓成分的性质、分离纯化技术及开发应用状况,并提出了目前研究工作的不足和今后的发展方向。 相似文献
72.
73.
F Chiarelli A Casani A Verrotti G Morgese L Pinelli 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(S425):42-45
Clinical diabetic nephropathy is a well-recognized cause of increased morbidity and mortality in patients with type 1 diabetes. The finding that microalbuminuria predicts progression to overt nephropathy has allowed early diagnosis and preventive interventions. Several studies have demonstrated that treatment with angiotensin-converting enzyme (ACE) inhibitors slows down the rate of decline of the glomerular filtration rate in type 1 diabetes patients with established proteinuria. The renoprotective properties of the ACE inhibitor captopril extend beyond its antihypertensive effects. ACE inhibitors represent the most appropriate class of antihypertensive drugs for treating type 1 diabetes patients because of their efficacy and safety. When microalbuminuria is detected and confirmed in a diabetic child or adolescent, and if it persists despite 6-12 months of improved metabolic control, treatment with ACE inhibitors should be started, even if the child is normotensive. Careful follow-up of renal function is essential. 相似文献
74.
尖吻蝮蛇毒中一种新类凝血酶的分离纯化 总被引:6,自引:1,他引:6
用阴离子交换色谱和凝胶过滤色谱技术,从尖吻蝮蛇毒中纯化得到一个具有凝血活性的组分.经Superdex 75 HR10/30预装柱检测,纯度达99.91%.SDS-PAGE显示为单一条带,还原、非还原条件下分子量分别为59.25k、52.58k.该组分的凝血酶比活为41.5u/mg,精氨酸酯酶比活为14.29u/mg,但不激活血浆凝血因子ⅩⅢ.EDTA不能抑制其凝血活性,而苯甲磺酰氟则产生不可逆抑制作用.结果表明该酶是一种新尖吻蝮蛇毒类凝血酶. 相似文献
75.
Abstract: Although the effect of sucrose on the physical stability of proteins has been well documented, its impact on their chemical stability is largely unknown. The aim of this study was to investigate the potential effects of sucrose on the structural conformation of human brain natriuretic peptide [hBNP (1–32)] and the synthetic human parathyroid hormone [hPTH (1–34)], and link these effects to chemical degradation pathways of these peptides. The stability of hBNP (1–32) and hPTH (1–34) was studied at pH 5.5. Aggregation was monitored using size exclusion high‐performance liquid chromatography (SE‐HPLC), whereas oxidation and deamidation products were measured by reversed phase (RP) HPLC. Fourier transform infrared (FT‐IR) spectroscopy was used to study the peptides’ conformation. Sucrose retarded aggregation, deamidation, and oxidation of hBNP (1–32) and hPTH (1–34), with a maximum effect at relatively high concentrations (as much as 1 m ). FT‐IR spectroscopy indicated that sucrose maintained the native conformation of hBNP (1–32) and induced small conformation changes in the hPTH (1–34) structure. Sucrose enhanced the stability of hBNP (1–32) and hPTH (1–34) in liquid formulations. The stabilizing effect of sucrose was due to a large extent to retardation of oxidation and deamidation of hBNP (1–32) and hPTH (1–34). 相似文献
76.
广州地区2001年~2003年抗高血压药物利用调查分析 总被引:2,自引:0,他引:2
目的:了解广州地区抗高血压药物的应用情况.方法:采用DDD分析法和金额排序法,对广州地区医院2001年~2003年间抗高血压药购入数据进行综合统计分析.结果:3年来,钙通道阻滞剂所占比例最大,平均为38.98%.其次是血管紧张素转换酶抑制剂(ACEI),平均为31.6%.合资药氨氯地平在DDDs排序及金额排序中均居首位.结论:钙通道阻滞剂、ACEI类药物为抗高血压的主流药,氨氯地平占有重要的临床地位. 相似文献
77.
目的通过考察不同pH值的无水乙醇对硝酸甘油注射液稳定性的影响,筛选出最适于硝酸甘油注射液生产的无水乙醇。方法用高温加热破坏试验及长期试验的方法研究硝酸甘油注射液的稳定性,考察指标pH值和含量。结论碱性杂质含量低的无水乙醇配制的硝酸甘油注射液稳定性最好,适于硝酸甘油注射液的生产。 相似文献
78.
三种螺距对种植体初期稳定性影响的有限元研究 总被引:10,自引:2,他引:8
目的:利用即刻负载有限元模型,研究种植体不同螺纹螺距因素对初期稳定性的影响。方法:利用Pro/E软件、Hypermesh软件及ABAQUS有限元软件,建立四类种植体即刻负载的三维有限元模型,比较3种螺纹螺距(0.8mm、1.6mm、2.4mm)在分别垂直和水平加载时,对种植体初期稳定性的影响。结果:对不同螺纹螺距种植体来说,垂直加载和水平加载时0.8mm螺距螺纹种植体微动最小,2.4mm螺距螺纹种植体微动最大。结论:螺纹的螺距对垂直相对位移有影响,对水平相对位移影响不大。随着螺距的增加,种植体对抗垂直向载荷的抵抗力减弱。水平加载时,螺纹的螺距对颈部微动影响不明显。 相似文献
79.
Vincent Yi-Fong Su Szu-Wen Ko Yuh-Lih Chang Yueh-Ching Chou Hsin-Chen Lee Kuang-Yao Yang Kun-Ta Chou Chia-Chen Hsu 《Allergy, asthma & immunology research》2022,14(3):314
PurposeCurrent clinical guidelines are unclear regarding the association of cardiovascular medication with the risk of acute exacerbation (AE) in patients with asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO).MethodsWe conducted a retrospective cohort study by interrogating the claims database of Taipei Veterans General Hospital. Patients with coexistent fixed airflow limitation and asthma were enrolled as an ACO cohort between 2009 and 2017. Exposure to cardiovascular medications, including angiotensin converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), non-selective beta-blockers, cardioselective beta-blockers, dihydropyridine (DHP) calcium channel blockers (CCBs), and non-DHP CCBs, in 3-month period each served as time-dependent covariates. Patients receiving a cardiovascular medication ≥ 28 cumulative daily doses were defined as respective cardiovascular medication users. Patients were followed up until December 31, 2018. The primary endpoint was severe AE, defined as hospitalization or emergency department visit for either asthma, COPD, or respiratory failure. The secondary outcome was moderate AE.ResultsThe final study cohort consisted of 582 ACO subjects, with a mean follow-up period of 2.98 years. After adjustment, ARB (hazard ratio [HR], 0.64, 95% confidence interval [CI], 0.44–0.93, P = 0.019), cardioselective beta-blocker (HR, 0.29, 95% CI, 0.11–0.72, P = 0.008) and DHP CCB (HR, 0.66, 95% CI, 0.45–0.97, P = 0.035) therapies were associated with lower risks of severe AE. ARB (HR, 0.42, 95% CI, 0.30–0.62, P < 0.001) and DHP CCB (HR, 0.55, 95% CI, 0.38–0.80, P = 0.002) therapies were associated with lower risks of moderate AE. Cardioselective beta-blockers, ARBs, and DHP CCBs were associated with lower risks of severe AE in frequent exacerbators. ACEI, non-selective beta-blocker, or non-DHP CCB use did not change the risk of severe AE.ConclusionsARB, cardioselective beta-blocker, and DHP CCB therapies may lower the risk of AE in patients with ACO. 相似文献
80.
ACE2基因多态性与原发性高血压的关系 总被引:2,自引:1,他引:1
目的 研究血管紧张素转化酶2(angiotensin converting enzyme 2,ACE2)基因多态性与广东地区原发性高血压的相关性.方法 高血压组选择门诊与住院的汉族无血缘关系的原发性高血压369例,男194例,女175例;对照组为同期体检的广东地区健康汉族居民199例,男101例,女98例.排除冠心病、高血压、糖尿病、脑血管病及肝功能不良、肾功能不良.按照性别分为两组,采用病例对照的原则,应用聚合酶链反应和限制性内切酶片段长度多态性(polymerase chain reaction and restriction fragment length polymorphism,PCR-RFLP)的方法检测ACE2基因G9570A多态性,并随机抽取20份标本进行基因测序以核实基因分型.在分析各亚组的年龄、体重指数、血压及生化指标的基础上综合分析ACE2基因多态性与原发性高血压的关系.结果 高血压组G等位基因频率:男75.3%,对照组男60.4%,差异有统计学意义(χ2=7.0086,P=0.0081),高血压组,女57.4%,对照组45.4%,差异有统计学意义(χ2=6.9443,P=0.0084);女高血压组GG基因型的频率明显高于对照组(χ2=12.9499,P=0.0015);G等位基因人群发生高血压的风险高于A等位基因人群,男OR:1.9945,95% CI:1.1916~3.3385,P=0.0082;女OR:1.603,95% CI:1.1274~2.2792,P=0.0085.结论 ACE2-G9570A多态性与原发性高血压相关;携带G等位基因的男性和仅仅携带G基因的女性人群发生高血压的危险性相对较大,提示ACE2基因可作为原发性高血压的候选易感基因. 相似文献