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1.
首先,以4-乙烯基吡啶(4-VP)与甲基丙烯酸二甲氨乙酯(DMAEMA)为单体通过自由基共聚,得到聚(4-乙烯基吡啶-co-甲基丙烯酸二甲氨乙酯)共聚物(P(4-VP-co-DMAEMA));然后,用1,3-丙磺酸内酯对P(4-VP-co-DMAEMA)侧链进行季铵化改性,得到不同离子化修饰程度的P(4-VP-co-DMAEMA)的两性离子共聚物(P(4-VPPS-co-DMAPS))。采用傅里叶转换红外光谱(FT-IR)、核磁共振氢谱(1H-NMR)和凝胶渗透色谱(GPC)对P(4-VP-co-DMAEMA)和P(4-VPPS-co-DMAPS)的化学结构进行表征。用万能拉力试验机、差示扫描量热分析仪(DSC)、热重分析仪(TG)以及稀释涂布平板法对P(4-VP-co-DMAEMA)和P(4-VPPS-co-DMAPS)薄膜的力学性能、热学性能以及抗菌/防污性能进行了表征。探究了单体单元物质的量之比、季铵化修饰程度对P(4-VPPS-co-DMAPS)薄膜材料物理化学性能以及功能性的影响。结果表明:当两种单体单元的物质的量之比(n4-VP/nDMAEMA)为3/7,离子化修饰程度为20%时,得到的两性离子共聚物薄膜具有一定的热稳定性、韧性和强度,且兼具优异的抗菌/防污特性。  相似文献   

2.
采用乳液聚合合成了一种可作为聚丙烯(PP)纤维可染改性添加剂的苯乙烯-苯乙烯磺酸钠共聚物P(St-co-NaSS)。通过傅里叶转换红外光谱仪(FT-IR)和核磁共振氢谱仪(1H-NMR)对共聚物的苯乙烯磺酸钠结构单元进行了表征,研究了反应条件对共聚物磺化度的影响;通过差示扫描量热仪(DSC)和热重分析仪(TG)研究了磺酸基团的引入对共聚物的玻璃化转变温度和起始分解温度的影响;通过旋转流变仪研究了磺化度对共聚物剪切黏度的影响;初步探讨了PP/P(St-co-NaSS)共混体系的染色性能。结果表明:当反应时间为2 h,反应温度为70℃,引发剂质量分数为0.6%,苯乙烯磺酸钠的摩尔分数为0.01时,共聚物的磺化度f=6.68%(零切黏度η0=19 620 Pa·s,属牛顿流体);在10-2~10-1 s-1的剪切速率范围内,P(St-co-NaSS)表现出假塑性流体的特征,具有较好的加工流动性。对于PP/P(St-co-NaSS)共混体系,使用阳离子染料染色时,染色深度(K/S值)为2.603 2,使用分散染料染色时,K/S值为10.168 8。P(St-co-NaSS)适合作为聚丙烯纤维的可染改性添加剂。  相似文献   

3.
首先,以丙烯酸(AA)、N-乙烯基吡咯烷酮(VP)和苯乙烯(St)为聚合单体,通过自由基共聚法合成了一种双亲无规共聚物P(AA-co-VP-co-St)。 然后,在疏水作用和静电作用的共同诱导下,将该共聚物与聚苯胺(PANI)共组装形成形态可控且均匀分散的PANI纳米粒子。通过透射电子显微镜和激光动态光散射等研究了P(AA-co-VP-co-St)和 PANI在水溶液中的共组装行为,并系统研究了亲水单体AA的物质的量分数对所制备的PANI纳米粒子粒径、形态的影响。结果表明:当AA物质的量分数为30%时,PANI纳米粒子的粒径最小。  相似文献   

4.
汪冬  肖艳 《医学教育探索》2017,30(4):450-456
首先以4-甲酸苄基哌啶内酯(NPIL)为原料,采用钯碳(Pd-C)催化加氢脱保护的方法合成了4-哌啶内酯单体(PIL);然后以苯甲醇为引发剂,分别采用酶(Novozym 435)和异辛酸亚锡(Sn(Oct)2)催化己内酯(CL)和PIL开环聚合,制备了阳离子共聚物聚(4-哌啶内酯)-co-聚己内酯(P(PIL-co-CL))。通过核磁共振氢谱(1H-NMR)、红外光谱(FT-IR)、凝胶渗透色谱(GPC)、差示扫描量热仪(DSC)等方法对共聚物的结构组成、数均分子量以及热性能等进行了表征。结果表明:成功制备了阳离子聚合物P(PIL-co-CL),相较于有机金属催化剂Sn(Oct)2,固定化酶Novozym 435催化内酯开环聚合表现出聚合可控且无副反应的优点。  相似文献   

5.
首先以正己胺为引发剂,引发肌氨酸-N-羧酸内酸酐(Sar-NCA)和谷氨酸苄酯-N-内酸酐(BLG-NCA)进行开环聚合制备共聚物,该共聚物经水合肼改性得到无规共聚物聚肌氨酸-co-聚谷氨酸酰肼(PSar-co-PGH);然后用高碘酸钠氧化海藻酸钠制备了氧化海藻酸钠(ALG-CHO);最后将不同浓度的PSar-co-PGH溶液和ALG-CHO溶液进行物理混合,制备了水凝胶。聚合物结构分别采用傅里叶红外光谱(FT-IR)和核磁共振氢谱(1H-NMR)进行表征;采用扫描电镜、红外光谱和旋转流变仪分别对其凝胶机理和力学性能进行表征。探讨了pH对水凝胶形成的影响。结果表明:成功制备了基于PSar-co-PGH/ALG-CHO的pH响应性水凝胶,水凝胶的储能模量随着PSar-co-PGH浓度的增大而增大。  相似文献   

6.
以单分散的苯乙烯-甲基丙烯酸甲酯共聚物(P(St-co-MMA))微球为载体,FeSO4·7H2O和FeCl3·6H2O为铁源,NaOH为沉淀剂,在氧化石墨烯(GO)存在下,利用反相共沉淀法通过原位复合技术在P(St-co-MMA)微球表面包覆磁性氧化石墨烯(P(St-co-MMA)/Fe3O4/GO)。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶变换红外光谱仪(FT-IR)、X射线衍射仪(XRD)、振动样品磁强计(VSM)和氮吸附-脱附等温线对P(St-co-MMA)/Fe3O4/GO样品的结构和性能进行表征分析。研究结果表明:纳米级的磁性氧化石墨烯成功地负载在了微米级的共聚物P(St-co-MMA)表面,所制备的P(St-co-MMA)/Fe3O4/GO微纳米复合物平均孔径为14.55 nm,孔体积为0.204 2 cm3/g,比表面积为56.14 m2/g。该复合物具有超顺磁性和良好的磁响应性,能够满足磁分离的要求。  相似文献   

7.
将甲基丙烯酸N,N-二甲氨乙酯(DMAEMA)和微量荧光单体4-丙烯酰氧基四苯乙烯(TPE-a)经自由基共聚合制备了共聚物Poly(DMAEMA-co-TPE-a)(PDT),并通过引入交联剂N,N-亚甲基双丙烯酰胺(Bis)和致孔剂N,N-二甲基甲酰胺(DMF)制备了pH敏感荧光多孔光纤。采用FT-IR、1H-NMR、TG和SEM表征了产物的结构,研究了产物的荧光和pH响应性能。研究表明,共聚物PDT具有聚集诱导发光(AIE)效应,并具有较好的pH响应性能;当单体、交联剂和致孔剂的物质的量之比为60:1:40时,制备的pH敏感荧光多孔光纤具有较好的耐热性能、内部结构和pH响应性能。  相似文献   

8.
选用苯并二噻吩(BDT)类衍生物作为给体单元D,并选用噻吩并吡咯二酮(TPD)类衍生物(A1)和噻吩并吡嗪(TP)类衍生物(A2)作为共同的受体单元,通过Stille偶联聚合制备了-(D-A1m-(D-A2n-型三元无规共聚物,并同时合成了基于BDT和TP的二元共聚物。采用核磁共振氢谱(1H-NMR)、凝胶液相色谱(GPC)和热重(TG)表征聚合物的结构与性能;采用紫外-可见光谱和循环伏安法测试聚合物的光电性能,研究了以这类聚合物为给体材料制备的太阳能器件的光伏性能。结果表明:三元无规共聚物具有较高的相对分子量和热稳定性,在太阳光范围具有强而宽的吸收,同时具有相对较低的最高电子占用轨道HOMO和最低电子占用轨道LUMO能级。基于三元无规共聚物P2的器件,其光电转换效率可达到1.22%,优于相应的二元共聚物P1的1.15%。  相似文献   

9.
L型丙交酯(LLA)、乙交酯(GA)和三亚甲基碳酸酯(TMC)为原料,辛酸亚锡为催化剂,通过开环聚合制备了丙交酯-三亚甲基碳酸酯二元共聚物(PLT)和丙交酯-三亚甲基碳酸酯-乙交脂(PLTG)三元共聚物。采用核磁共振氢谱、傅里叶红外光谱、体积排阻色谱、差热扫描、力学性能测试、血液相容性实验表征了产物的结构与性能,研究了共聚物组成对其结晶能力、热性能和力学性能的的影响。结果表明:所得聚合物的数均分子量均在8×104以上,多分散系数在2.0以下。共聚物中的TMC和GA链段使其结晶能力、玻璃化转变温度和拉伸强度与L型聚丙交酯相比均有所下降。三元共聚物PLTG的拉伸强度可达到22.3 MPa,断裂伸长率达到168.7%。另外,共聚物的血液相容性优良。  相似文献   

10.
利用单体对之间的氢键特殊相互作用,采用一步反应在水相中共聚甲基丙烯酸(MAA)、丙烯酰胺(AM)和交联剂乙二醇二甲基丙烯酸酯(EGDMA),制备了pH响应性共聚物P(MAA-co-AM)纳米水凝胶。采用纳米粒度与电位分析仪、傅里叶红外光谱仪、透射电子显微镜、场发射扫描电镜等对P(MAA-co-AM)纳米水凝胶的尺寸、形貌、组成和结构进行了表征。系统研究了反应参数对P(MAA-co-AM)纳米水凝胶的影响。结果表明:当两单体等物质的量投料时所制备的P(MAA-co-AM)纳米水凝胶粒径分布最窄(〈Dh〉=129 nm,PDI=0.095),且其粒径随着两单体用量的增加而增大。随着单体加入时间的延长或EGDMA用量的增加,P(MAA-co-AM)纳米水凝胶的粒径逐渐变小。P(MAA-co-AM)纳米水凝胶表现出极好的pH响应性:当介质的pH从4增加到8时,溶胀比高达7,体积扩张了343倍。  相似文献   

11.
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   

12.
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   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
In recent years, the author of this essay has applied electro-acupuncture combined with the trigger point needle-embedding for treatment of primary trigeminal neuralgia in 31 cases, yielding satis- factory results as reported in the following.  相似文献   

18.
Objective: To explore the role of matrix metalloproteinase-1,2 (MMP-1, MMP-2) and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) in endometriosis. Methods: The eutopic and ectopic endometria from 40 subjects suffering from endometriosis and regular.endometria from 40 subjects (excluding endometriosis) were collected and examined by in situ hybridization technology and western blot assay. Results: Both expressions of MMP-1 and -2 were stronger in ectopic endometrium and eutopic endometrium than in normal endometrium. On the contrary, the expression of TIMP-1 in ectopic endometrium and eutopic endometrium was lower. The differences were significant (P 〈 0.01 ). Moreover, there was no relationship among the expressions of MMP-1, 2 and TIMP-1 in ectopic endometrium. Conclusion: The expressions of MMP-1, 2 and TIMP-1 lose balance and lack of periodic changes in ectopic endometrium , which explains the biological invasive behavior of endometriosis. It was suggested-that regulating the balance between the MMPs and TIMP-1 should be an ideal therapeutic target to endometriosis.  相似文献   

19.
Prof. SHI Da-zhuo, Ph.D., male, was born on March 20, 1960. Prof. SHI entered the Ph.D. program in 1990 at the China Academy of Chinese Medical Sciences under the supervision of Prof. CHEN Ke-ji, majoring in the treatment of cardiovascular diseases. After receiving his Ph.D. degree in 1993, Prof. SHI started working at the Cardiovascular Center in Xiyuan Hospital affiliated to China Academy of Chinese Medical sciences.  相似文献   

20.
《中国结合医学杂志》2008,14(2):159-159
The 6th National General Congress of Chinese Association of Integrative Medicine (CALM) was convened at 19-20, April 2008 in Beijing. Academician CHEN Zhu, the minister of Ministry of Health indicated at the congress that the integration of Chinese and Western medicine is very well in keeping with the situation of our country and the general rule of development in medical science; and as a good integration of Chinese medicine and Western medicine, it is mutually beneficial and advantageous to both of them. Seeing the creativity shown in integrative medical investigation in theoretic and methodological sides, we should and must persist in and develop it.  相似文献   

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