PLLA-PDLA共混熔体的流变性能

将两种不同构型的聚L-乳酸（PLLA）与聚D-乳酸（PDLA）共混、熔融、挤出、压制成圆形薄片,利用高级旋转流变仪测试其流变性能。结果表明,聚乳酸共混熔体(PLLA-PDLA)属于典型的切力变稀非牛顿流体,其黏流活化能较大,表观黏度对温度变化敏感度高;随温度的升高共混熔体PLLA-PDLA的结构黏度指数减小,非牛顿指数增加。成核剂（TMP）的加入,使共混熔体PLLA-PDLA的非牛顿指数n减小、结构黏度指数Δη增大、可纺性下降,当m(TMP)/m(PLLA-PDLA)=0.5%时共混熔体PLLA-PDLA的可纺性相对较好。     

大分子相容剂改性Mg(OH)2/PP阻燃材料的性能

用双螺杆挤出机熔融挤出法制备了相容剂改性氢氧化镁/聚丙烯[Mg(OH)2/PP]阻燃材料。研究了马来酸酐接枝聚丙烯(PP-g-MA),马来酸酐接枝(乙烯/辛烯)共聚物(POE-g-MA)和马来酸酐接枝聚醋酸乙烯酯(EVA-g-MA)3种大分子相容剂对阻燃材料的熔体流动性、结晶行为、力学性能和断口形态的影响。结果表明:相容剂PP-g-MA和POE-g-MA的加入使阻燃材料的熔体流动速率降低,PP结晶温度提高,EVA-g-MA的加入使阻燃材料熔体流动速率数提高;Mg(OH)2对PP结晶存在异相成核作用,Mg(OH)2的加入使PP的冲击强度、拉伸强度和断裂伸长率降低,杨氏模量提高;相容剂改性后Mg(OH)2/PP阻燃材料的拉伸强度提高,其中以PP-g-MA最为明显,而POE-g-MA则提高了阻燃材料的冲击强度。     

纤维素与己内酰胺的接枝共聚反应

以过硫酸铵和过硫酸钾为引发剂,在碱性环境下进行纤维素与己内酰胺的接枝共聚反应。采用红外光谱仪(FT-IR)、扫描电子显微镜(SEM)及X射线衍射仪(XRD)对接枝共聚物的分子结构、表观形貌和结晶性进行了表征。通过单因素实验重点考察了单体用量、引发剂浓度、反应温度和反应时间等对接枝共聚物接枝率的影响。结果表明：以3 g纤维素为原料,当单体与原料质量比为1∶1、引发剂浓度为0.2 mol/L、反应温度30 °C、反应时间75 min时,接枝率最高可达57%。由XRD衍射图谱可知,接枝反应发生在纤维素的无定形区,没有破坏原纤维素的结晶结构。     

两亲共聚物SMASS对水煤浆流变学性能的影响

合成了一系列接枝率不同的两亲性共聚物分散剂——对氨基苯磺酸接枝马来酸酐-苯乙烯共聚物(SMASS),并用氢核磁共振及红外光谱对其结构进行了表征。通过测量接触角,发现该分散剂能有效改善煤表面的亲水性;运用高级旋转流变仪研究了水煤浆自身浓度、分散剂及其用量对水煤浆流变性能及稳定性的影响。实验结果表明分散剂能有效降低水煤浆的表观黏度和屈服应力,大幅提高水煤浆的稳定性,并且发现接枝率为0.28的SMASS1效果最好。进一步对比了接枝率均为0.50左右的SMASS2(接枝率为0.49)和氨基萘磺酸接枝马来酸酐-苯乙烯共聚物SMANS2 (接枝率为0.50),及一种木质素类商用添加剂(AD)对水煤浆降黏增稳的影响,发现SMASS2的综合效果最好。由此证明,SMASS是一种新型有效且相对廉价的水煤浆分散剂,具有良好的工业应用前景。     

幂律流体流变特性的研究

本文以聚丙烯酰胺(PAM)水溶液为对象进行了实验测定,同时归纳了CMC水溶浓等其它非牛顿幂律流体的有关文献数据,得出了幂律流体的流动特性指数n和稠度指数K与分子量M、溶液浓度C、温度T之间的关联式。此结果可用于推算PAM水溶液或其它类似的幂律流体的流变指数n和K,也可用以研究它们的非等温流动问题。     

中国成年人全血触变特性的研究

作者应用Low Shar-30流变测定仪,据Huang氏方程,用改良的方法测定了314名健康中国人(男160名,女154名)全血触变参数。提出了男、女两性全血触变参数的正常值范围。两组血浆粕度(η_0)和纤维蛋白原无明显差异。男子组红细胞压积(HCT)、屈服应力(τ_0)、粘度的牛顿分量(μ)、非牛顿分量(η_s-μ)、表观粘度(η_s)(2.378~(-1))、结构参数平衡值(A)、红细胞叠连解聚反应的表观速率常数(ARC)均比女子组明显增高。本研究还发现,随着年龄增大,纤维蛋白原和血浆粘度有增高趋势,男女老年组比青年组明显增高。男女老年组的HCT、τ_0、μ、η_s、(η_s-μ)和A明显比青、中年组低。有趣的是男女两组ARC与年龄的关系是有差别的,其机理有待进一步研究。     

功能化SEBS的制备与结构

采用熔融反应接枝的方法将(3-异氰酸酯基-4-甲基)苯氨基甲酸-2-丙烯酯(TAI)引入到聚苯乙烯-b-聚(乙烯-co-丁烯)-b-聚苯乙烯三嵌段共聚物(SEBS)上,以实现SEBS的功能化。以傅里叶红外光谱（FT-IR）、核磁共振波谱（NMR）、凝胶渗透色谱（GPC）、动态力学分析（DMA）等手段对接枝物进行了表征。研究了引发剂、单体用量对接枝率及熔体流动速率的影响。结果表明：单体TAI的自聚倾向低,已成功接枝到SEBS上,接枝后的SEBS分子量高且分子量分布宽,接枝后聚(乙烯-co-丁烯)段的玻璃化转变温度提高。     

通用聚丙烯的偶联反应

通过熔融接枝的方法在聚丙烯（PP）分子链上接枝甲基丙烯酸缩水甘油酯（GMA）,制得PP接枝物PP-g-GMA,然后采用多个胺基的偶联剂聚六亚甲基胍（PHMG）对其进行偶联反应,制备偶联的聚丙烯（MPP）。通过与通用聚丙烯（EPS）以及进口专用料（PF-814）的对比,考察了经过偶联改性的MPP熔体的流变特性。结果表明：与原料EPS和PF-814相比,改性后MPP熔体的低频剪切区储能模量、挤出胀大、稳态柔量、零剪切黏度及熔体强度等都有明显增大。     

梳型共聚物SMAC对硅胶石蜡熔融共混体系流变学性能的影响

用硅胶石蜡熔融共混体系来模拟熔铸炸药非均相体系的流变特性。通过改变硅胶的疏水化程度以及硅胶在体系中的质量分数来研究非均相体系流变学性能。改变硅胶与石蜡间的相互作用是调控非均相体系流变学性能最有效的方法之一。根据这一发现,制备了两亲性的梳型共聚物十八胺接枝马来酸酐 苯乙烯共聚物( SMAC ),通过改变十八胺的接枝度以及SMAC在非均相体系中的质量分数可以大大降低非均相体系的稳态黏度。     

血液流变学对眼葡萄膜炎的临床意义分析

目的:对血液流变学在眼葡萄膜炎的内源性病因以及预防、治疗和防止复发等方面的临床意义作初步的探讨。方法:对80例眼葡萄膜炎病人作血液流变学检验。结果:血液黏度(ηb)、微循环滞留时间(MST)两项指标的增高最为显著;红细胞压积(HCT)有较显著的增高;血栓形成系数(TFL)明显升高;血液还原黏度(ηr)、血浆黏度(ηp)、纤维蛋白原(PFC)以及血细胞聚集系数(VAI)等四项指标都有平均44%的阳性率。结论:血液流变学检验对眼葡萄膜炎的内源性病因以及预防、治疗有重要的临床意义。     

Value of D-Dimers in patients with acute aortic dissection

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.     

Research of combined liver-kidney transplantation model in rats

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.     

BLOOD PRESSURE CHANGE WITH AGE IN SALT-SENSITIVE TEENAGERS

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.     

安心颗粒对急诊经皮冠状动脉介入术后生活质量影响的研究

目的：评价使用安心颗粒对急诊经皮冠状动脉介入术（PPCI）术后生活质量的影响.方法：将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组（术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次）和对照组（仅接受基础药物治疗）.所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表（MIDAS）、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果：入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异（P＞0.05）;出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低（P＜0.05）;组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低（P＜0.05）.两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血（P＞0.05）.两组发生轻度血小板减少症的患者数比较无差异（P＞0.05）.结论：PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.     

The comparative studies of the influences of Urapidil and Nicardipine on sino-atrial node function, atrio-ventricular node function and hemodynamics

Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P＜0.01);the MAP decreased(P＜0.01)and the HR increased drastically(P＜0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.     

Expression of OPGmRNA and ODFmRNA in the patients of hip fracture due to osteoporosis

Objective：To investigate the gene expression of osteoprotegerin（OPG） and osteoclast differentiation factor（ODF） in the bone tissue of patients with hip fracture due to osteoporosis. Methods：OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers（over 50 years old） with hip fracture（Observer Group） and 30 cases of hip facture sufferers with no osteoporosis（Control group） were analyzed with the Semi-Quantitative RT-PCR method. Results：The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion：Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.     

Dynamic Changes in Serum Estradiol and Progesterone levels in Patients of Premenstrual Syndrome with Adverse Flow of Liver-qi

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.     

Real-time Three-dimensional Echocardiography in Assessment of Left Ventricular and Right Ventricular Volumes

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.     

SCREENING FOR A 21-CHROMOSOME ABNORMALITY IN PREIMPLANTED EMBRYOS OF ELDERLY WOMEN

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.     

Scientific principles and rigorous processes should be followed in developing clinical guidelines for therapeutic interventions of integrative medicine

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.