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1.
溶剂对黄芩素-烟酰胺共晶形成热力学的影响   总被引:1,自引:1,他引:0  
考察了黄芩素-烟酰胺共晶在乙酸乙酯、丙酮和氯仿中的形成热力学。通过测定25℃下黄芩素、烟酰胺及黄芩素-烟酰胺共晶在这3种溶剂中的溶解度,建立了不同溶剂中黄芩素-烟酰胺-溶剂三相图。结果显示,黄芩素-烟酰胺共晶在3种溶剂中均符合1∶1溶液络合模型,共晶的形成为热力学自发反应(ΔG0<0),与其他两种溶剂相比,共晶在氯仿中形成的ΔG0绝对值最小,且在氯仿为溶剂的三相图中共晶形成区域远离化学计量比线。本研究利用热力学研究方法为选择共晶制备用溶剂及优化共晶制备条件奠定了理论和应用基础。  相似文献   

2.
共晶技术提高黄芩素溶出度及生物利用度的研究   总被引:3,自引:1,他引:2  
采用混悬液结晶法制备1∶1物质的量比的黄芩素-咖啡因(BE-CA)共晶,以提高BE的溶出度及口服生物利用度。差示扫描热分析、X射线粉末衍射法、傅里叶红外光谱法等分析表明所制备的共晶为区别于BE及CA的一种长针状晶体新物质。溶出试验表明BE-CA共晶的溶出度均显著高于BE晶体及其与CA的晶体混合物。大鼠体内药代动力学研究表明,与BE相比,BE-CA共晶缩短BE及其活性代谢物黄芩苷(BI)的达峰时间(tmax),并显著提高了BE及BI的峰浓度(cmax)及血药浓度-时间曲线下面积(AUC),极大地提高了黄芩素口服生物利用度。  相似文献   

3.
目的 观察不同血液净化方式对中分子尿毒症毒素β2-微球蛋白(β2-MG)、甲状旁腺素(PTH)等的清除效果,为临床合理选择尿毒症患者血液净化方式提供依据。方法 研究是64例在笔者医院进行血液净化治疗的尿毒症患者,同时根据血液净化方式的差异进行分组∶单纯血液透析组(HD,n=30),血液透析合并血液灌流组(HD+HP,n=15),血液透析滤过组(HDF,n=19)。采集治疗前后患者血清,ELISA法检测β2-MG、PTH水平以评价不同净化方式对中分子尿毒症毒素的清除率;检测临床肾功能指标和钙离子(Ca2+)、钾离子(K+)、钠离子(Na+)、氯离子(Cl-),反映不同净化方式对低分子物质的清除率。结果 与HD、HD+HP组比较,HDF组治疗后血液中分子物质β2-MG和PTH水平均显著下降(P<0.01),清除效果明显;与HD组比较,HD+HP组治疗后PTH显著下降(P<0.01),治疗后β2-MG的清除率比较,差异无统计学意义(P>0.05);3组BUN、Scr清除率、KT/V值透析前后血差异无统计学意义,Ca2+、K+、Na+、Cl-改善比较,差异无统计学意义(P>0.05)。结论 对于尿毒症患者体内毒素的清除,HDF的清除效果最佳,其次是HD+HP,HD对中分子物质的清除无明显效果。  相似文献   

4.
将中空纤维膜反应器和芬顿试剂结合脱除烟气中的Hg0。研究了不同参数以及SO2、NO和O2等杂质气体对Hg0脱除的影响。结果表明:随着H2O2浓度、Fe2+浓度、溶液初始pH和温度的增加,Hg0脱除率先增加后降低,其最佳工作条件是H2O2浓度为6 mmol/L,Fe2+浓度为9 mmol/L,溶液初始pH为2.5,温度为20℃;增大液气比和通过减小气相流量增大停留时间均对Hg0脱除有增强作用,当液气比超过0.11时,Hg0的脱除率不再增加;当气相流量为0.6 L/min时,Hg0脱除率超过85%;SO2、NO对Hg0的脱除有抑制作用,O2对Hg0的脱除几乎没有影响;还测定出温度20℃下中空纤维膜反应器的比相界面积a=270.29 m-1和传质动力学参数kL=8.13×10-4 m/s,kG=0.786×10-6 mol/(m2·s·Pa)。  相似文献   

5.
[目的] 优选制备黄芩素-茶碱共晶的溶剂体系,通过体外溶出实验考察共晶对黄芩素和茶碱各自溶出度的影响。[方法] 通过测定黄芩素-茶碱共晶在茶碱-乙酸乙酯、茶碱-甲醇和茶碱-丙酮溶液中的溶解度,得出三相平衡点,绘制黄芩素-茶碱-溶剂体系的三元相图,筛选最优溶剂体系制备共晶,并以人工肠液和人工胃液为溶出介质,对共晶进行体外溶出度评价。[结果] 丙酮溶液体系中的共晶形成区面积大于乙酸乙酯、甲醇。通过丙酮溶剂挥发法制备的共晶中,黄芩素在人工肠液和人工胃液中的累积溶出度分别是原料药的1.38和2.02倍,分别是物理混合物的1.27和1.80倍。两种介质中共晶对茶碱均起到了一定的缓释作用。[结论] 共晶的形成能够促进难溶性成分黄芩素的体外溶出度,并且对茶碱的溶出度有一定延缓作用,为黄芩素-茶碱共晶的进一步研究和临床应用提供了借鉴。  相似文献   

6.
通过水相法制备3-巯基丙酸(MPA)稳定的碲化镉量子点(CdTe QDs),即MPA-CdTe QDs。研究Cu2+对发射波长为599 nm的MPA-CdTe QDs荧光猝灭效应,发现Cu2+浓度与荧光猝灭强度之间满足Stern-Volmer修正方程的线性关系。通过多项式拟合得出Cu2+浓度在2.28×10-6~18.24×10-6 mol/L和4.8×10-7~12×10-7mol/L两个区间范围内与MPA-CdTe QDs的荧光强度F0/F的多项式关系分别为:F0/F=7.999-2.470c+0.339c2F0/F=3.154-0.160 c+0.049 c2,拟合度分别为0.991,0.993。MPA-CdTe QDs对Cu2+检测限可达1.326×10-7 mol/L。  相似文献   

7.
通过均匀设计法优化双半胱乙酯(ECD)药盒的处方。以ECD药盒中A瓶的pH、B瓶的氯化亚锡含量为考察因素,以药盒与99m TcO4 -标记后得到配合物的放射化学纯度为考察指标,通过效应值曲面图确定优化处方,最后进行验证。试验优化得到回归方程y=0.567+0.103x1+9.68e-4x2-9.86e-4x13-5.48e-8x23。结合效应值曲面可知,当A瓶的pH为6.4、氯化亚锡含量为65μg时,试验结果最佳。验证结果表明,理论预测值与实测值接近,优化处方后的产品明显优于现行产品。实验结果表明,采用均匀设计法得到的结果,可以对ECD药盒的处方进行优化。  相似文献   

8.
纪康康  张学勇  廖荣丰 《安徽医学》2018,39(9):1039-1043
目的 对比分析Goldmann眼压计(GAT)和非接触眼压计(NCT)在FS-LASIK手术前后眼压测量值一致性及其变化。方法 选取2016年12月至2017年9月于安徽医科大学第一附属医院行FS-LASIK手术的近视患者154例(303只眼),采用横断面研究,对比评估手术前后GAT测量值(IOP-GAT)和NCT测量值(IOP-NCT)的变化及一致性,分析该眼压测量变化值与年龄、术前等效球镜绝对值(|SEpre|)、术前眼压测量值(IOP-GATpre、IOP-NCTpre)、术前中央角膜厚度(CCTpre)、切削深度(AD)、切削比(AR)及术前曲率半径(Rpre)的相关性,并给出逐步回归公式。结果 154患者的IOP-GATpre平均为(15.60±2.39)mmHg、IOP-NCTpre的平均为(15.49±2.58)mmHg,两者差异无统计学意义(P=0.192),而Bland-Altman分析IOP-GATpre与IOP-NCTpre平均值差值为0.11 mmHg,其95%一致性界值为(-2.83,3.06)mmHg。术后IOP-GAT、IOP-NCT均较术前下降,差异有统计学意义(P<0.05),IOP-NCT下降程度更大。手术前后GAT测量变化值(ΔIOP-GAT)与|SEpre|、IOP-GATpre、CCTpre、AD、AR呈正相关(P<0.05),与年龄、Rpre无明显相关(P>0.05)。回归方程为:ΔIOP-GAT=0.635×IOP-GATpre+15.633×AR-8.554(R2=0.504,F=204.163,P<0.05);NCT测量变化值(ΔIOP-NCT)与年龄、|SEpre|、IOP-NCTpre、CCTpre、AD、AR呈正相关(P<0.05),与Rpre无明显相关,回归方程:ΔIOP-NCT=0.603×IOP-NCTpre+20.493×AR-5.994(R2=0.653,F=274.921,P<0.05)。结论 FS-LASIK手术前后IOP-GAT、IOP-NCT均不具有较好一致性,术后两者均明显下降,IOP-NCT下降程度更大,两者下降程度与多种因素相关,但均与术前眼压测量值的相关性最高。  相似文献   

9.
设计并熔制了作为蓝宝石充填材料用的SiO2-TiO2-RO-R''2O(其中R代表二价碱金属离子Ba2+、Zn2+,R''代表一价碱金属离子Na+、K+)系列玻璃。通过对玻璃的物理性能(密度和折射率)、热稳定性(玻璃化转变温度和析晶温度)以及玻璃骨架结构的探讨,研究了混合碱效应对玻璃性能的影响。结果表明,该系列玻璃在n(Na+):n(K+)=2:3时,其密度、折射率等物理性能符合蓝宝石充填要求,且热稳定性强,充填过程不容易发生析晶,可作为蓝宝石充填材料。  相似文献   

10.
兰瑞家 《医学教育探索》2011,42(9):1715-1718
目的 研究姜黄素(CU)与牛血清白蛋白(BSA)之间的作用机制。方法 采用变温试验研究二者之间的猝灭类型,求算结合数(n)和结合常数。结果 静态猝灭是导致BSA荧光猝灭的主要原因,CU与BSA结合反应的平衡常数(K0)为5.26×106(21 ℃)和4.60×106(31 ℃),n为1.35。通过计算结合反应的热力学参数,推断CU与BSA之间的作用力以疏水力为主。结论 荧光法适合于研究CU与蛋白质的结合反应,具有简便快速、灵敏度高等优点。  相似文献   

11.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

12.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

13.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

14.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

15.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

16.
A clinical guideline for the therapeutic interventions of integrative medicine may be defined as a written document which states a series of recommendations on therapeutic interventions of integrative medicine for a special disease or condition. The guideline may provide assistance to medical professionals in making clinical decisions aimed at improving the clinical outcome of patients and reducing the costs of medical care(~'4~. Recommendations issued by a guideline should be based on the best available evidence in both Western and Chinese medicine. For fulfilling this purpose, the development of clinical guidelines for therapeutic interventions in the field of integrative medicine should follow scientific principles and undergo a rigorous processes.  相似文献   

17.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

18.
Journal of Nanjing Medical University (English Edition) JNMU, sponsored by Nanjing Medical University, was established in 1987. It is a bimonthly comprehensive English medical journal published locally and abroad.Since 2007, Journal of Nanjing Medical University (English Edition )was granted Elsevier the full publishing and distribution rights worldwide for the Electronic Edition, excluding the People's Republic of China.  相似文献   

19.
Objective To measure Derpl and Blot5 allergen levels in asthmatics' homes in Hongkong.Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients' house: bed and floor. Derpl and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique.Results The levels of Derpl allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g)and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P=0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derpl and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P< 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 =0 μg/g of dust as compared with Derpl in bed and on the floor (4.3% and 14.5% respectively, P< 0.05).Conclusions Derpl and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus (Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hongkong.  相似文献   

20.
ANTI-PROLIFERATION EFFECT OF ORIDONIN ON HL-60 CELLS AND ITS MECHANISM   总被引:4,自引:0,他引:4  
Objcetive To investigate the anti-proliferation effect of oridonin on leukemic HL-60 cells and its mechanism. Methods HL-60 cells in vitro in culture medium were given different concentrations of oridonin. The inhibitory rate of cells were measured by microculture tetrazolium (MTT) assay, cell apoptotic rate was detected by flow cytometry (FCM), morphology of cell apoptosis was observed by hoechst 33258 fluorescence staining, and the activity of telomerase was detected using telomere repeat amplification protocol (TRAP) PCR-ELISA before and after apoptosis occurred. Results Oridonin could decrease telomerase activity, inhibit growth of HL-60 cells, and cause apoptosis significantly. The suppression was both in time- and dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by hoechst 33258 fluorescence staining especially after cells were treated 48-60 hours by oridonin. Conclusions Oridonin has apparent anti-proliferation and apoptotic effects on HL-60 cells in vitro, decreasing telomerase activity of HL-60 cells may be one of its most important mechanisms. These results will provide strong laboratory evidence of oridonin for clinical treatment of acute leukemia.  相似文献   

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