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991.
目的比较3D打印个性化截骨工具辅助(patient-specific instrumentation,PSI)下人工全膝关节置换术(total knee arthroplasty,TKA)与传统TKA的手术精确度和临床疗效。方法自2017年9月至2018年12月,将40例拟接受初次膝关节置换患者随机分为2组,每组均为20人。一组应用个性化截骨工具辅助TKA手术(PSI组),另一组接受传统TKA(对照组)。比较两组患者的冠状面下肢机械轴线、手术时间、术中出血量、术后引流量以及HSS评分。结果对照组和PSI组的手术时间分别为(103.3±18.7) min和(91.3±15.7) min;术中出血量分别为(372.0±53.0)mL和(332.8±47.0)mL;术后引流量分别为(378.8±97.2)mL和(315.0±89.0)mL。两组手术时间、术中出血量、术后引流量比较差异均有统计学意义(P0.05)。对照组和PSI组术后2周HSS评分分别为(89.3±2.8)分和(88.7±2.9)分,两组比较差异无统计学意义(P0.05)。对照组和PSI组术后全下肢力线差值分别为(1.9±1.1)°和(1.2±1.0)°,冠状面股骨假体角度(frontal femoral component angle,FFC)差值分别为(2.1±1.1)°和(1.1±0.9)°,两组比较差异有统计学意义(P0.05)。冠状面胫骨假体角度(frontal tibia component angle,FTC)差值分别为(1.3±0.8)°和(1.4±0.8)°,两组比较差异无统计学意义(P0.05)。结论PSI辅助TKA较传统TKA手术时间更短、术中出血量更少,并且术后冠状面全下肢力线及股骨力线的改善优于传统TKA手术。 相似文献
992.
基于离散小波变换提取脑机接口中脑电特征 总被引:13,自引:0,他引:13
在脑机接口中,针对脑电特征提取利用单一种类信息、使用数据量大、分类性能较差等缺点,提出一种新颖的基于离散小波变换的方法。分析了小波变换特征提取的特点和特征表示方式,用Daubechies类db4小波函数对脑电信号进行6层分解,抽取小波变换各子带关键的部分逼近系数、小波系数、小波子带系数均值组成特征向量。以分类正确率为指标检验了提取特征的性能。实验结果表明,这种方法能够利用少量数据提取脑电信号本质特征,具有较高的分类性能,为利用脑电识别人的不同意图提供了快速而有效的手段。 相似文献
993.
Experiments on (CBA x C57BL)F1 mice showed that injection of hydrocortisone into the animals in a dose of 1 mg per mouse 24 h after immunization with sheep's erythrocytes, and against the background of repeated injections of EDTA, leads to a reduction in the relative number of plaque-forming cells by more than two-thirds in the spleen of the mice compared with the effect of the two agents separately, and by more than five-sixths compared with the control. It is suggested that this may be the result of the more intensive incorporation of hydrocortisone associated with the prolonged hypocalcemic action of the complexone, EDTA.Laboratory of Regulation of Immunopoiesis, Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 3, pp. 320–322, March, 1978. 相似文献
994.
M. D. Mashkovskii K. M. Lakin M. S. Ovnatanova G. Ya. Shvarts 《Bulletin of experimental biology and medicine》1976,81(3):379-381
The effect of Parmidine (pyridinolcarbamate) on platelet aggregation, blood coagulation, and fibrinolysis was studied in rabbits. After direct addition of Parmidine to platelet-enriched plasma aggregation of the platelets produced by serotonin (5-HT) and adrenalin was reduced. After oral administration of Parmidine to animals, aggregation induced by ADP, 5-HT, and adrenalin was inhibited, blood coagulation was reduced, and fibrinolysis was accelerated.Laboratory of Pharmacology, S. Ordzhonikidze All-Union Pharmaceutical Chemical Research Institute. Department of Pharmacology, Therapeutic Faculty, Moscow Medical Stomatological Institute. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 3, pp. 322–324, March, 1976. 相似文献
995.
996.
Vrolijk JM Kaul A Hansen BE Lohmann V Haagmans BL Schalm SW Bartenschlager R 《Journal of virological methods》2003,110(2):201-209
Overall treatment results of chronic hepatitis C have improved markedly with the introduction of pegylated interferon-alpha (PEG–IFN-) and ribavirin combination therapy. However, cure rates in the most common genotype 1 infection are still unsatisfactory. IFN- dose–response studies on viral kinetics suggest that inadequate dosing might be a key factor but drug levels have hardly been tested, which is in part due to difficulties in measuring this cytokine in patient samples. We have shown recently that hepatitis C virus (HCV) replicons are highly sensitive to IFN-. In this report we tested whether the replicon system could be used as a sensitive bioassay to determine the amount of biologically active IFN- in serum or heparinized plasma of patients under therapy. To facilitate the measurements, a stably replicating subgenomic HCV RNA was developed that carries the gene encoding the firefly luciferase. Dose response studies with IFN- demonstrate that the amount of expressed luciferase directly correlates with the level of HCV replication. By using this cell-based assay, serum samples of HCV patients treated with different types and doses of IFN- were analyzed in parallel to IFN- standards made by serial dilutions of the same type of IFN- the patient was treated with. Based on nonlinear logistic models serum concentrations corresponding to 1.3–19 U/ml were determined in patients under standard or high dose IFN- therapy, and from 3.8 to 4.1 ng/ml in patients treated with PEG IFN-. In conclusion, the HCV-replicon based bioassay allows determining the levels of biologically active IFN- in serum and heparinized plasma of patients under treatment. 相似文献
997.
Novel pH-sensitive hydrogels were developed as suitable candidates for carriers in bioMEMS devices as well as for oral delivery of therapeutic peptides and proteins due to their ability to respond to environmental pH change. Macromonomers containing various PEG molecular weights were synthesized and used to prepare P(MAA-g-EG) hydrogels were by photopolymerization. P(MAA-g-EG) hydrogels showed a drastic change of the equilibrium swelling ratio between pH 2.2 and 7.0. At pH 7.0, hydrogels with PEGMA2000 exhibited higher swelling ratio than hydrogels with PEGMA1000. For both hydrogels with PEGMA1000 and PEGMA2000, the swelling mechanism became more relaxation-controled as the environmental pH changed from 2.2 to 7.0 due to the ionization of the functional groups in polymer networks at high pH. In vitro release studies of insulin were conducted. P(MAA-g-EG) hydrogels exhibited drastic increase of insulin release as the pH of the medium was changed from acidic to basic. Insulin release from P(MAA-g-EG) hydrogels with PEGMA2000 was slower than from hydrogels with PEGMA1000 at both low and high pH. These results were used to design and improve protein release behavior from these carriers. 相似文献
998.
大鼠肺微血管内皮细胞培养及其粘弹性研究 总被引:4,自引:0,他引:4
为了建立肺微血管内皮细胞培养方法 ,研究肺微血管内皮细胞粘弹性。我们取大鼠肺周边组织 (宽度不应大于 1.5 mm) ,将组织剪成 1.5 mm× 1mm× 1mm的组织块 ,贴入无菌的 2 5 cm3培养瓶 ,每瓶 10~ 15块 ,同时加入含 2 0胎牛血清、肝素 90 U/ml、L-谷氨酰胺 4mmol、青霉素 10 0 U/ml和链霉素 10 0 μg/ml的 DMEM培养基 3ml,放入 37℃二氧化碳培养箱中静置培养 ;8h后翻转培养瓶 ,6 0 h后取出肺组织块 ,接着继续培养 2~ 4d后进行传代。最后消化分离肺微血管内皮细胞 ,用微管吸吮系统研究肺微血管内皮细胞粘弹性。结果显示 :肺微血管内皮细胞通过倒置相差显微镜观察 ,细胞呈鹅卵石镶嵌状排列 ,状如梭形或多角形 ,大小均匀 ,胞核清晰 ,呈卵圆形 ,胞浆丰富 ; 因子相关抗原免疫荧光染色呈阳性 ;肺微血管内皮细胞弹性模量 K1 =49.3± 9.2 Pa、K2 =73.2±2 4.8Pa、粘性系数 μ=19.2± 7.2 Pa.s。这些结果表明用组织块法培养肺微血管内皮细胞是可行的 ,肺微血管内皮细胞表现出较大的刚性 相似文献
999.
目的 在江苏淮阴一母系遗传非综合征型耳聋大家系中,寻找线粒体基因组上可能影响1555(A→G)突变表型的其他位点突变。方法 采用聚合酶链反应-限制性片段长度多态性分析(PCR-restriction fragment length polymorphism,PCR-RFLP)和测序技术。检测了核心分支家系中27名母系成员的线粒体DNA上1555位点和7445位点的碱基变化,进而对该家系2名母系成员的线粒体全基因组和其他25名母系成员线粒体12S rRNA基因MTRNR1和tRNA-Ser^(UCN)基因MTTS1进行了全长测序。结果 再次证明了1555(A→G)突变是该家系成员致聋的分子生物学基础之一;并发现该家系27名母系成员的线粒体基因组中除1555(A→G)突变外,还同时存在有955-960(insC)同质型突变,两突变共分离。另外,新发现一个线粒体DNA突变——7449(insG),但该突变仅在2名母系成员中存在。结论 推测955-960(insC)突变可能通过改变12S rRNA基因的高级结构,并与1555(A→G)突变协同作用,提高了突变携带者对氨基糖甙类药物的敏感性;同时该突变可能也会导致线粒体蛋白质的合成缺陷。从而提高1555(A→G)突变致聋的外显率。 相似文献
1000.
Objective To study the function of 4 different haplotypes cDNA which are constructed by two non-homonymy single nueleotide polymorphism (SNP) sites C19170G (Leu45Val) and C30799G (Ala500Gly) in the coding region of human CⅡTA gene. Methods HeLa cells were transfeeted with eu-karyotic expression vectors containing four different haplotypes cDNA. C Ⅱ TA mRNA and HLA classⅡanti-gen (HLA-DR, DP, DQ) were respectively detected by RT-PCR and indirect cell immunofluoreseence tech-nique in the untransfected and transfeeted with four eukaryotic expression vectors and empty vectors HeLa cells. The quantity of HLA classⅡ antigen were analyzed by flow eytometry. Results No expression of CⅡTA mRNA and HLA class Ⅱ antigen were observed on original HeLa cells and empty vector transfected cells. CⅡTA mRNA expression was emerged, and the expression of HLA class Ⅱ antigen were observed in the HeLa cells transfected with eukaryotic expression vectors containing four different haplotypes cDNA. And there were not significantly different with the levels of HLA class Ⅱ antigen expression among HeLa cells transfected with eukaryotic expression vectors containing four different haplotypes cDNA ( P > 0.05 ). Con-dusion The SNP of Chinese at the sites C19170G(Leu45Val) and C30799G(Ala500Gly) in the coding site of C Ⅱ TA gene did not influence capability of CⅡTA trans-aetivating HLA class Ⅱgene expression. 相似文献