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1.
NEWTECHNIQUEOFBIOCHEMANALYZINGNEWTECHNIQUEOFBIOCHEMANALYZINGYinWelcai(PLAGENERALBOSPITAL)NEW TECHNIQUE OF BIOCHEM ANALYZING...  相似文献   

2.
ANEWANALYTICALMETHODFORO2ANDCO2TRANSFERINSHELL-AND-TUBE(INTRA-LUMINALFLOW)OXYGENATORSANEWANALYTICALMETHODFORO2ANDCO2TRANSFERI...  相似文献   

3.
P物质对人多形核白细胞功能的影响   总被引:3,自引:0,他引:3  
目的研究P物质(SP)对人多形核白细胞(PMN)有关方面作用及可能的意义。方法应用硝基四氮唑蓝(NBT)还原法,荧光法和Griess反应等测定不同浓度SP单独或在细菌衍生肽类似物FMLP甲酯存在下对PMN产生超氧阴离子(O-2,)过氧化氢(H2O2),一氧化氮(NO)和PMN膜上一功能酶中性内肽酶(NEP)活性及膜流动性的影响。结果SP(≥10-5mol/L)可剌激PMN显著产生O-2,H2O2和NO,后者被L-单甲基精氨酸(NMMA)所抑制;SP(10-8~10-4mol/L)能显著增加FMLP甲酯剌激PMN产生H2O2,并显浓度递增依赖性;SP与FMLP甲酯协同可下调NEP活性;SP能提高PMN膜流动性。结论SP可通过PMN介导调节炎症反应,对PMN的杀菌功能有增强作用,SP对PMN的这些影响可能是神经系统参与炎症和免疫调节的途径之一。  相似文献   

4.
为探讨血小板活化因子(PAF)对肾小球系膜细胞(GMC)产生活性氧的调节作用,本研究观察了PAF对体外培养的大鼠GMC产生超氧化物阴离子(O)和过氧化氢(H-2O-2)的影响。结果表明10 ̄(-9)M/L的PAF已能诱导GMC产生O和H2O2(1.14±0.42nmol/10 ̄5GMC、0.97±0.16nmol/10-5GMC),这一效应呈剂量依赖性;溶PAF无诱导GMC产生活性氧作用;特异性PAF受体拮抗剂BN52021抑制PAF的刺激作用,抑制作用也呈剂量依赖性,5×10 ̄(-5)M/LBN52021完全抑制GMC合成活性氧。本研究说明PAF可诱导GMC合成活性氧。  相似文献   

5.
LIGHTSCATTERINGPROPERTYOFHUMANBLOODATTHEWAVELENGTHOF810NMLIGHTSCATTERINGPROPERTYOFHUMANBLOODATTHEWAVELENGTHOF810NMJianZhong;D...  相似文献   

6.
将人HGF完整编码区cDNA片段插入MBP表达型pMAL-C2载体质粒中,构建了表达人HGF/MBP融合蛋白的pMAL-MBP/HGF重质粒。表达的HGF/MBPGE分析分子量约为110kD,Westernblotting表明能被兔抗MBP抗体和抗人HGFMcAb所识别。  相似文献   

7.
CHANGESOF6-K-PGF1aRELEASEFROMTHELUMINALSURFACEOFDACRONSEEDEDWITHAUTOLOOUSVENOUSTISSUEFRAGMENTSCHANGESOF6-K-PGF1aRELEASEFROMTH...  相似文献   

8.
STUDYONMECHANISMOFTHEBIOEFFECTSOFTRANSIENTELECTROMAGNETICPULSESTUDYONMECHANISMOFTHEBIOEFFECTSOFTRANSIENTELECTROMAGNETICPULSEW...  相似文献   

9.
PRELIMINARYRESEARCHOFHUMANHEPATOCYTECELLLINEASTHEBIOLOGICALMATERIALOFELADPRELIMINARYRESEARCHOFHUMANHEPATOCYTECELLLINEASTHEBIO...  相似文献   

10.
本文应用常规淋巴细胞杂交瘤技术制备了4株能稳定分泌抗人重组红细胞生成素(rHuEPO)单克隆抗体(McAb)的小鼠杂交瘤细胞系BⅡ1B5、DⅡ6B9、MⅡ1H4和GI3E7。用鼠单克隆抗体分型试剂盒鉴定,其分泌的McAb的类分别是IgM、IgM、IgG1和IgG2a。间接ELISA法测定细胞上清的效价为1×10-2~1.25×10-4,腹水效价为1×10-2~1×10-8。培养上清经ELISA鉴定,与IL-2、GM-CSF、IFN-α等细胞因子均无交叉反应,只与rHuEPO特异性结合。  相似文献   

11.
A-B-A type block copolymers of poly(gamma-benzyl L-glutamate) (PBLG, A segment) and polydimethylsiloxane (PDMS, B segment) and PDMS (trunk)-PBLG (branch) graft copolymers were synthesized, and the permeation of oxygen in water and the permeation of oxygen and carbon dioxide in the dry state were investigated. The gas permeation coefficient (P) increased with increasing content of PDMS. However, PCO2/PO2 values of copolymer films were in the range 6-9, i.e. larger than 5.4 for PDMS film. The oxygen permeation in water suffered from the interfacial resistance, which was reduced by the hydrolysis of film surface. The Arrhenius plot of the gas permeation coefficient in the dry state of the block copolymer B showed a turning point at about 40 degrees C. This temperature is close to beta-peak temperature (39 degrees C) and may be ascribed to the molecular motion of the PBLG segment. Transmission electron microscopy showed that one of the block copolymer films (PDMS 46 mol%) appears to have PDMS segments dispersed in the PBLG matrix (island-in-sea structure) and one of the graft copolymer films (PDMS 58 mol%) appears to take a lamellar structure. The gas permeation across the graft copolymer film appears to occur through the continuous PDMS phase, leading to a near-negligible activation energy in this process.  相似文献   

12.
The film surface of poly(gamma-benzyl-L-glutamate) (PBLG) was modified with 2-aminoethanol to enhance its hydrophilicity. Controlling the reaction conditions of PBLG and 2-aminoethanol, various types of copoly(gamma-benzyl-L-glutamate, gamma-hydroxyethyl-L-glutamine) film surfaces were obtained. Surface free energy (gamma sv), the dispersive component of gamma sv (gamma dsv), the nondispersive component of gamma sv (gamma psv), and the interfacial free energy of polymer surface with water (gamma sw), which were obtained by using the contact angle measurement and calculation method proposed by Andrade et al., were changed remarkably by the aminolysis. The gamma sv value increased after 2 h of aminolysis from 48.2 (PBLG) to 65.3 dyn/cm and gradually increased to around 70 dyn/cm after 12 h reaction. (gamma dsv) and (gamma psv) changed from 31.0 and 17.2 dyn/cm (PBLG) to 26.5 and 44.3 dyn/cm, respectively. These parameters of the material surfaces, modified over 12 h reaction, were found to be similar to those of the surfaces of canine aorta, vein, and human fibrin membrane. Blood clotting times on these polymer surfaces were comparatively longer than on siliconized glass surfaces.  相似文献   

13.
Hydroxyl-terminated polybutadiene (HTPB)-based polyurethane with dimethyol propionic acid (DPA) as chain extender was synthesized by solution polymerization. The HTPB-based polyurethane was modified by UV radiation with N-isopropyl acrylamide monomer to get poly(N-isopropyl acrylamide)-modified polyurethane (PUDPANIPAAm). The cohesive energy (E(coh)), molar volume (V), solubility parameter (delta), molecular weight (W(M)), volume per gram (V(g)), and the density (1/V(g)) of PUDPANIPAAm were calculated by group contribution methods. To evaluate the application of PUDPANIPAAm for wound dressing and transplantation of cell sheet, the measurement of water content, water vapor transmission rate, and gas permeation on the PUDPANIPAAm membrane was evaluated. The biocompatibility of these membranes, cell adhesion, and proliferation assay were conducted in the cell culture. The effect of thermosensitivity of poly(N-isopropyl acrylamide) on cell detachment was also evaluated in the primary study. The results showed that these PUDPANIPAAm membranes are thermosensitive. The modification of PU with poly(N-isopropyl acrylamide) reduced the water vapor transmission rate and permeability of gas through PUDPANIPAAm membrane. PUDPANIPAAm membranes could support cell adhesion and growth. Owing to the thermosensitive nature of poly(N-isopropyl acrylamide), the relative cell numbers detached from PUDPANIPAAm membranes were larger than those detached from the polystyrene dish.  相似文献   

14.
The purification of human adipose-derived stem cells (hADSCs) from human adipose tissue cells (stromal vascular fraction) was investigated using membrane filtration through poly(lactide-co-glycolic acid)/silk screen hybrid membranes. Membrane filtration methods are attractive in regenerative medicine because they reduce the time required to purify hADSCs (i.e., less than 30 min) compared with conventional culture methods, which require 5–12 days. hADSCs expressing the mesenchymal stem cell markers CD44, CD73, and CD90 were concentrated in the permeation solution from the hybrid membranes. Expression of the surface markers CD44, CD73, and CD99 on the cells in the permeation solution from the hybrid membranes, which were obtained using 18 mL of feed solution containing 50 × 104 cells, was statistically significantly higher than that of the primary adipose tissue cells, indicating that the hADSCs can be purified in the permeation solution by the membrane filtration method. Cells expressing the stem cell-associated marker CD34 could be successfully isolated in the permeation solution, whereas CD34+ cells could not be purified by the conventional culture method. The hADSCs in the permeation solution demonstrated a superior capacity for osteogenic differentiation based on their alkali phosphatase activity, their osterix gene expression, and the results of mineralization analysis by Alizarin Red S and von Kossa staining compared with the cells from the suspension of human adipose tissue. These results suggest that the hADSCs capable of osteogenic differentiation preferentially permeate through the hybrid membranes.  相似文献   

15.
Summary: This paper focuses on the addition of tert‐butylcalix[4]arene (CA) to cross‐linked poly(dimethylsiloxane) (PDMS) membranes derived from poly(dimethylsiloxane) di(methyl methacrylate) macromonomer (PDMSDMMA) and various divinyl cross‐linker compounds, on the pervaporation characteristics for the removal of dilute benzene from an aqueous solution. When an aqueous solution of 0.05 wt.‐% benzene was permeated through the cross‐linked PDMSDMMA membranes containing CA they showed high benzene/water selectivity and permeability. Both the benzene/water selectivity and permeability of the membranes were enhanced by increasing both the divinyl compound cross‐linker content and the amount of CA, and were significantly influenced by the type of divinyl compound. Addition of CA to PDMSDMMA membranes cross‐linked with divinylperfluorohexane (DVF) showed the best pervaporation performance. The normalized permeation rate, benzene/water separation factor, and pervaporation separation index of these membranes were 1.86 × 10−5 kg · m/(m2 · h), 5 027, and 9 350, respectively. The pervaporation characteristics of the cross‐linked PDMSDMMA membranes containing CA were studied with respect to their chemical and physical structure. Furthermore, the mechanism of the selective permeation of benzene over water through these membranes was investigated.

  相似文献   


16.
五味子酚对突触体膜脂质过氧化损伤保护作用的ESR研究   总被引:3,自引:0,他引:3  
本文用自旋标记方法研究了经过脂质过氧化作用后脑突触体膜的生物物理特性的变化以及抗氧化剂五味子酚对膜的保护作用.用脂肪酸标记物5-DOXYL和16-DOXYL标记研究了膜脂流动性,结果表明,受脂质过氧化损伤后膜脂流动性降低;用马来酰亚胺自旋标记研究了脂质过氧化对脑突触体膜蛋白上巯基的影响,结果发现,脂质过氧化后,ESR波谱的弱强固定化比值W/S增大,总的效应表现为膜蛋白上巯基结合位点裸露程度变大。加入五味子酚后能抑制膜流动性的降低,且能使弱强固定化比值W/S趋向于未受脂质过氧化损伤的突触体膜的弱强固定化比值W/S,证明了五味子酚能降低脂质过氧化对膜的损伤程度,对膜起保护作用。  相似文献   

17.
Summary: Preparation of organic‐inorganic hybrid membranes and their pervaporation permeation and separation characteristics for an aqueous solution of 0.05 wt.‐% benzene are described. In this study, we prepared organic‐inorganic hybrid membranes by the sol‐gel reaction of tetraethoxysilane (TEOS) as an inorganic component with poly(methyl methacrylate‐co‐vinyltriethoxysilane) (P(MMA‐co‐VTES)) and poly(butyl methacrylate‐co‐vinyltriethoxysilane) (P(BMA‐co‐VTES)) as organic components. When an aqueous solution of dilute benzene (0.05 wt.‐%) was permeated through the P(MMA‐co‐VTES)/TEOS and P(BMA‐co‐VTES)/TEOS hybrid membranes, the benzene concentration in the permeate through all hybrid membranes was higher than that in the feed solution. This result demonstrates that these hybrid membranes are benzene selective for an aqueous solution containing dilute benzene. The benzene/water selectivity of the P(BMA‐co‐VTES)/TEOS hybrid membrane was about 20 times higher than that of the P(MMA‐co‐VTES)/TEOS hybrid membrane. Specifically, the P(BMA‐co‐VTES)/TEOS hybrid membrane with a TEOS content of 75 mol‐% showed the highest benzene/water selectivity. The benzene/water selectivity of the hybrid membranes depended significantly on the cross‐linked structures formed by the sol‐gel reaction of VTES and TEOS.

Effects of the TEOS content on the sorption selectivity (○) and the diffusion selectivity (?) for an aqueous solution of 0.05 wt.‐% benzene through P(MMA‐co‐VTES)/TEOS and P(BMA‐co‐VTES)/TEOS hybrid membranes at 40 °C.  相似文献   


18.
The permeation and separation characteristics of poly(vinyl chloride) (PVC) and poly[(vinyl chloride)-co-(vinyl acetate)] (poly(VC-co-VAc)) membranes were investigated for aqueous organic acid solutions by pervaporation and evapomeation. The PVC membrane preferentially incorporates organic acids and predominantly permeates water from aqueous organic acid solutions. Water permselectivities of these aqueous solutions through the PVC membrane are significantly dependent on high diffusivity of water across the membrane. It was found that the permeation rate increases and the separation factor for the water permselectivity decreases with increasing vinyl acetate (VAc) content in the poly(VC-co-VAc) membrane. Preferential solubility of acetic acid into the poly(VC-co-VAc) membrane increases with the VAc content. This result was explained by a strong affinity between acetic acid and the VAc unit in the poly(VC-co-VAc) membrane.  相似文献   

19.
The orientation effect of galactose ligand on hepatocyte attachment was investigated. Poly(N-p-vinylbenzyl-o-β-D-galactopyranosyl-D-gluconamide)(PVLA, a β-galactose-carrying styrene homopolymer, was used as a model ligand for the asialoglycoprotein receptors on hepatocytes. PVLA was transferred onto the poly(γ-benzyl L-glutamate) (PBLG) or PBLG/poly(ethylene glycol) (PEG)PBLG Langmuir-Blodgett (LB) films as the monolayer level. The dichroic fluorescence values of the confocal microscope indicated that the PVLA transferred onto the LB films was located with a preferential orientation of its molecular axes with regard to the direction of the α-helix of polypeptide. Hepatocyte recognized well-oriented galactose moieties of the surface of PVLA through asialoglycoprotein receptors.  相似文献   

20.
血透氧化铝透析膜的生成及膜的特性实验研究   总被引:2,自引:0,他引:2  
研究氧化铝膜生成的不同反应条件与膜孔特性之间的关系,以探讨符合透析膜结构特性的氧化铝膜最佳生成条件。分别以3%硫酸、5%硫酸和2.7%草酸为电解液,反应温度恒定在0℃、反应时间为48h,在不同的电压条件下,将高纯度铝箔氧化生成氧化铝膜。用扫描电镜观察、测定膜的孔径,有效多孔和多孔性。测定氧化铝膜对水的传导力,评估膜的选择通透性。实验结果显示:在我们的实验条件下,能稳定地生成膜孔孔径均匀、排列整齐规则的氧化铝膜。在相同的电解液中,随着电压的增加,生成氧化铝膜的孔径和多孔性显著增大(P<0.05),有效多孔性显著减小(P<0.05)。在3%和5%硫酸电解液中氧化生成的氧化铝膜的孔径比在2.7%草酸中生成的膜孔径小。本实验条件下生成的氧化铝膜对水的传导力比目前临床上使用的一些透析器膜的水传导力大。研究结果表明,生成符合透析膜结构特性的氧化铝膜的最佳反应条件是以3%硫酸或5%硫酸为电解液、反应温度0℃、反应时间48h、反应电压12.5~17.5V。  相似文献   

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