可生物降解的pH敏感水凝胶的合成及其溶胀性能研究

采用明胶和聚乙烯醇为原料，制备了戊二醛交联、明胶／聚乙烯醇配比不同的水凝胶，并用FTIR和SEM对产物进行了表征。研究了凝胶的溶胀动力学，结果表明，原料配比对各种凝胶的溶胀速率影响不大，而对平衡溶胀比与原料配比有关，室温下凝胶的平衡溶胀比在300％～500％之间。pH敏感性研究表明，几种凝胶均表现出明显的pH响应性，当溶胀介质的pH值在明胶等电点附近时，水凝胶的溶胀比达到最小值，凝胶的溶胀-消溶胀动力学曲线呈“W”形，即该凝胶具有形状记忆功能。     

明胶-聚异丙基丙烯酰胺水凝胶的溶胀动力学

采用明胶（Gel)和N－异丙基丙烯酰胺（NIPAM）为原料，制备了Gel/聚异丙基丙烯酰胺（PNIPAM）水凝胶系列；研究了原料配比、pH值及温度对水凝胶溶胀速度的影响。结果表明，当温度大于PNIPAM的最低临界溶液温度（LCST）值时，Gel/PNIPAM水凝胶的溶胀速度随着组分中PNIPAM的增加而降低，且溶胀过程以扩散渗透控制为主。而pH对水凝胶溶胀速度的影响与温度有关。Gel/PNIPAM配比为5／5，温度大于LCST时，水凝胶的pH敏感性受明胶控制；温度低于LCST时，pH对水凝胶的溶胀速度的影响很小。     

纳米纤维素晶体-聚乙烯醇水凝胶的制备及性能表征

通过冷冻-解冻的方法制备了纤维素纳米晶体（CNC）-聚乙烯醇（PVA）复合水凝胶。考察了CNC含量对PVA水凝胶力学性能、溶胀行为、热性能及内部形貌结构的影响。研究结果表明,CNC的加入可大幅提升PVA水凝胶的力学性能,m(CNC)/m(PVA)=1%的CNC-PVA水凝胶的拉伸强度、杨氏模量与断裂伸长率,分别较纯PVA水凝胶提升了60%、110%和70%。此外,CNC还促进了PVA水凝胶的溶胀,使溶胀平衡时间缩短,溶胀度增加。     

基于丙烯酰氧乙基三甲基氯化铵导电水凝胶的制备及性能检测

目的：筛选出机械性能优良并且导电性优异的水凝胶的最优配方。方法：以丙烯酰氧乙基三甲基氯化铵（DAC）为主要基质,以N,N-亚甲基双丙烯酰胺（BisAAm）为化学交联剂,以1-羟环己基苯酮为催化剂,同时加入甘油和羟乙基纤维素（HEC）制备出复合导电水凝胶,并测量其导电性、黏性、拉伸性能和压缩性能。结果：以DAC为基质,通过BisAAm、甘油以及HEC进行配比添加后,该凝胶与3M导电水凝胶相比无异味和残留,长期稳定性好不变色,也无细菌滋生。通过适当配比添加甘油及HEC后,其导电性、黏性、拉伸性能和压缩性能均优于传统的3M导电水凝胶（P＜0.05）。通过老鼠皮肤接触实验发现,该水凝胶具有良好的生物安全性。结论：DAC的含量为60%,BisAAm的含量为5%,甘油含量为10%,HEC含量为0.015%为水凝胶最优组合。     

丝素蛋白-聚氨酯水凝胶的制备和性能

以异佛尔酮二异氰酸酯（IPDI）、聚乙二醇（PEG）、聚氧化丙烯二醇（PPG）等为主要原料,合成了一系列—NCO封端的水性聚氨酯（PU）预聚体,与自制的丝素蛋白（SF）水溶液混合进行交联反应,制备出丝素蛋白聚氨酯（SF-PU）水凝胶。研究了SF-PU水凝胶的合成工艺,对SF-PU水凝胶进行了红外和电镜表征及性能测试,并对其溶胀动力学以及结构与性能之间的关系进行了研究。研究表明：成功合成了具有三维结构、溶胀响应性良好的SFPU水凝胶。     

二乙烯基砜交联的可德胶化学水凝胶的制备与表征

以二乙烯基砜（DVS）作为交联剂通过亲电加成反应制备了可德胶化学水凝胶。采用傅里叶变换红外光谱（FT-IR）、扫描电子显微镜（SEM）和质构分析手段表征了所得凝胶的结构与性能,并对其形貌、溶胀率以及水凝胶的力学性质与制备条件的关系进行了研究。结果表明：所得凝胶网络结构较为致密均匀,溶胀率依赖于交联度。可德胶化学水凝胶的强度和韧性可以通过DVS的用量、可德胶的浓度和碱溶液的浓度进行调控。     

聚（N，N＇-二乙基丙烯酰胺）水凝胶的制备及其溶胀动力学

以N,N′-二乙基丙烯酰胺(DEA)为单体,偶氮二异丁腈(AIBN)为引发剂,分别采用疏水性的1,2-二乙烯苯(DVB)和水溶性的N,N′-亚甲基双丙烯酰胺(BIS)为交联剂制备了温度敏感水凝胶聚(N,N′-二乙基丙烯酰胺)(PDEA).制得的PDEA水凝胶的低临界溶解温度(LCST)在30 ℃附近,初步讨论了交联剂的用量和性质对水凝胶性能的影响.并对其在不同温度下达到溶胀平衡时的溶胀比,去溶胀动力学及干凝胶的再溶胀动力学过程进行了研究.     

辐射形成的低分子量PEO水凝胶的理化性能研究

目的;研究电子束辐射交联的聚氧化乙烯（ＰＥＯ）Ｒ－１５０水凝胶膜及其溶胀水凝胶膜的理化性能。方法：应用电子加速器照射聚合物ＰＥＯ Ｒ－１５０水溶液制备成水凝胶及溶胀水凝胶后,测定其理化性能。结果：ＰＥＯ Ｒ－１５０水凝胶的交联密度与辐射剂量呈正相关（Ｐ〈０．０１）。聚合物浓度对其不明显（Ｐ〉０．０５）。ＰＥＯ Ｒ－１５０水凝胶的溶胀度与辐射剂量呈负要关（Ｐ〈０．０１）,与其浓度呈正相关（Ｐ〈０．０     

温度与pH快速响应性P(NIPAM-co-AAc) 水凝胶的制备及其性能

以氯化钠水溶液作为反应介质,成功制备了温度与pH快速响应性聚(N-异丙基丙烯酰胺-co-丙烯酸)［P(NIPAM-co-AAc)］水凝胶,研究了氯化钠水溶液的浓度对凝胶性能的影响。通过红外光谱(FT-IR)﹑扫描电镜(SEM)﹑测溶胀比对凝胶性能进行了表征。结果表明:凝胶具有相同的化学组成与结构,但具有不同的微观形态;随着反应介质中氯化钠浓度的增加,凝胶在20 ℃蒸馏水中的平衡溶胀比增大,并表现出较强的温度与pH敏感性以及较快的去溶胀速率。     

PMAA纳米水凝胶的水相制备

利用表面活性剂间的疏水作用以及表面活性剂与单体间的氢键作用,促使甲基丙烯酸(MAA)单体在原位生成的聚甲基丙烯酸甲酯(PMMA)种子乳胶表面的选择性聚合,实现了PMAA纳米水凝胶的水相"绿色"制备。利用动态光散射、傅里叶红外光谱、透射电子显微镜表征了PMAA纳米水凝胶的尺寸、组成、形貌和pH响应性。研究了聚氧乙烯失水山梨醇单月桂酸酯(吐温20)的用量、N,N'-亚甲基双丙烯酰胺(MBA)的用量、MAA的用量和加入方式、十二烷基硫酸钠(SDS)的补加速率等对PMAA纳米水凝胶的尺寸和溶胀性能的影响。结果表明:PMAA纳米水凝胶为核-壳结构;随着MBA用量的减小、吐温20用量的增加、MAA用量的增加,PMAA纳米水凝胶的尺寸和溶胀比均增大;当采用半连续加入MAA时,PMAA纳米水凝胶的尺寸和溶胀比变小;当SDS的补加时间由60 min延长到100 min时,PMAA纳米水凝胶的尺寸逐渐变小。PMAA纳米水凝胶具有良好的pH响应性,当介质的pH从1增加到6时,其流体力学体积扩张了64倍。     

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.     

The clinicopathological and immuohistochemical analysis of solid-pseudopapillary tumor of the pancreas： report of 9 cases

Objective：To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas（SPTP）. Methods：Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin（HE） staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results：Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin（9/9 cases）, AAT（9/9 cases）, NSE（9/9 cases）, ACT（7/9 cases）, CK20（2/9 cases）, CgA（1/9 cases）, S-100（3/gcases）, PR（4/gcases）, Syn（3/9 cases） and CD56（5/9cases）, negative in CEA and ER. Conclusion：SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.     

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.