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1.
PGR-08理化性质及生物活性的研究   总被引:9,自引:0,他引:9  
许鸿源  许鸿章  杨美纯  周岐伟 《广西植物》2003,23(5):461-463,469
PGR-0 8是从某种土壤放线菌 (Actinomyces)的发酵液中分离提纯得到的白色结晶 ,纸层析和熔点检测证明它是化学单体 ,mp 1 80~ 1 81℃ ,[α]2 1D+ 4 3°(H2 O)。溶解性试验表明它易溶于 H2 O(≥ 6 0℃ )、HCl、Na OH、(CH3 ) 2 CO、CH3 OH和 C2 H5OH等 ,但不溶于 Na HCO3 。Tollen、Fehling和 Ag NO3 -溴酚兰等专性试剂的颜色反应表明其组成成分中有嘌呤和糖。生物试验证明 :PGR-0 8具有细胞分裂素的活性 ,例如它能减缓蒲公英离体叶圆片 Chl.的降解 ,延长叶圆片寿命 1~ 2倍以上 ,诱导叶圆片分化出不定根或不定芽 ,甚至建成小植株。它还能促进小麦种子萌发。  相似文献   

2.
本公司自行研制了基因工程重组肠激酶 (EK)和重组烟草花叶蚀刻病毒蛋白酶 (TEV) ,广泛应用于重组融合蛋白表达的制备中。该产品质量达到国外同类产品 (Invitrogen和GIBCO Life)的要求 ,可长期低温保存。两种蛋白酶均由大肠杆菌表达制备 ,带 6个组氨酸标记 ,容易从制品中除去。两种酶产品纯度均达到 95% ,酶活性均为每毫克蛋白含 1 0 0 0 0活性单位。欢迎科研单位和企业购买 ,价格仅为国外进口的 2 0 % ,可按客户要求提供不同包装。欢迎国内试剂公司代理。联系人 :张益电话 传真 :0 2 3 6 86 996 76、6 8888852E mail:fankai1 96 3@ya…  相似文献   

3.
本公司自行研制了基因工程重组肠激酶 (EK)和重组烟草花叶蚀刻病毒蛋白酶 (TEV) ,广泛应用于重组融合蛋白表达的制备中。该产品质量达到国外同类产品 (Invitrogen和GIBCO Life)的要求 ,可长期低温保存。两种蛋白酶均由大肠杆菌表达制备 ,带 6个组氨酸标记 ,容易从制品中除去。两种酶产品纯度均达到 95% ,酶活性均为每毫克蛋白含 1 0 0 0 0活性单位。欢迎科研单位和企业购买 ,价格仅为国外进口的 2 0 % ,可按客户要求提供不同包装。欢迎国内试剂公司代理。联系人 :张益电话 传真 :0 2 3 6 86 996 76、6 8888852E mail:fankai1 96 3@ya…  相似文献   

4.
目的:比较四种胃蛋白酶原检测试剂的性能。方法:使用Beckman Coulter AU5800全自动生化分析仪,采用免疫比浊法,对两种国产和两种进口蛋白酶原检测试剂的校准和质控、精密度、线性范围、检测灵敏度、前带反应影响和抗干扰能力进行比较。结果:四家公司的校准和质控指标均达到合格标准,两家进口试剂变异系数较小,在线性、准确性、灵敏度、前带反应等指标全面领先。结论:综合各项指标判断,目前使用的胃蛋白酶原检测试剂以两种进口产品性能为佳,国产品尚有一定差距。  相似文献   

5.
Folin-Ciocalteu比色法测定铜藻中褐藻多酚含量的研究   总被引:1,自引:0,他引:1  
以没食子酸为标准品,使用福林酚(Folin-Ciocalteu)试剂,通过紫外-可见分光光度法,对铜藻中褐藻多酚的含量进行了测定。结果表明,测定波长为760 nm,显色试剂Folin-Ciocalteu的用量为1.25 m L,0.1 g/m L Na2CO3溶液用量为4.0 m L,定容至10 m L,显色温度为30℃,反应时间为60 min,多酚含量在15~50μg/m L范围内与吸光度呈良好线性关系,回归方程为Y=0.0138X+0.0267,R2=0.9993。本测定方法的平均回收率为96.18%,相对标准偏差(RSD)为2.44%。该方法的稳定性、重现性、精密度以及加标回收率的相对标准偏差均符合要求,可用于铜藻中褐藻多酚含量的测定。按照本方法测定铜藻中褐藻多酚的平均含量为17.36 mg/g(RSD=1.25%)。  相似文献   

6.
为狂犬疫苗生产质量控制建立简便、高效、精准的糖蛋白体外效力分析方法,研制适用于狂犬疫苗生产质量控制的狂犬病毒糖蛋白酶联免疫吸附(ELISA)定量分析试剂。采用双抗体夹心法建立狂犬病毒糖蛋白ELISA定量分析体系,优化反应各项参数后考核试剂性能。线性范围为1~180 mIU/mL,灵敏度为0.4497 mIU/mL,分析内变异系数为5.8%~8.2%,分析间变异系数为7.2%~14.4%。用自制试剂与National Institutes of Health(NIH)动物法平行检测10份疫苗相关样品,两种方法测定结果的相对系数r2为0.8943,相关性良好。自制ELISA试剂各项性能指标良好,且与NIH动物法检测结果相关性良好,有望推广用于狂犬疫苗生产质量控制。  相似文献   

7.
目的检测3种益生菌制剂的稳定性,了解其所含活菌的稳定性信息。方法按药物稳定性试验指导原则进行加速稳定性试验和长期稳定性试验。加速稳定性试验在第0、1、2、3、6个月各检测1次,共5次;长期稳定性试验在第0、3、6个月各检测1次,共3次。制剂1的加速条件为(30±2)℃、相对湿度(65±5)%,长期条件为(18±2)℃、相对湿度(60±10)%;制剂2、3的加速条件为(25±2)℃、相对湿度(60±10)%,长期条件为(6±2)℃、相对湿度(60±10)%。检测项目包括崩解时限检查、干燥失重检测和活菌计数。结果 3种益生菌制剂在实验前后含水量等指标相对稳定,菌种含量有轻微变化,除制剂1中的嗜酸乳杆菌外,其余菌种含量均较稳定,在标示含量范围内(均P0.05)。结论 3种益生菌制剂在加速条件和长期条件下稳定性均较好,生物学特性未发生明显改变。  相似文献   

8.
HPLC法测定国产葡萄酒中白藜芦醇的含量   总被引:4,自引:0,他引:4  
采用HPLC法测定国产葡萄酒中白藜芦醇的含量。色谱条件为 :Shim packCLC ODS柱 (15 0mm× 6 0mm) ,流动相 :0 2mol/LH3 PO4 CH3 CN(2 0∶80pH 3 0~ 3 5 ) ,在 30 6nm测定。测得 15种国产葡萄酒中通化干红葡萄酒的白藜芦醇含量最高为 5 6 0mg/L。该方法灵敏 ,重现性好  相似文献   

9.
研制破伤风类毒素抗体酶联双抗原夹心法定量检测试剂,用于破伤风免疫血浆抗体效价检测。以精制破伤风类毒素经Sephacryl S-300柱层析纯化后作为包被抗原,用辣根过氧化物酶以改良过碘酸钠法标记精制破伤风类毒素作为酶标记抗原,以破伤风人免疫球蛋白国家标准品采用小鼠中和试验法标定试剂盒定量标准品,制备双抗原夹心法定量检测试剂;进行试剂盒检测范围、特异性、重复性、精密度及稳定性考核,并与小鼠中和试验法、琼脂双扩散法及国外破伤风类毒素抗体酶联试剂盒进行比较。结果显示,试剂盒的检测范围为10~150mIU/ml,灵敏度为10mIU/ml,线性好(r>0.996),板内孔间变异度小(CV<8%),特异性强(100%),重复性好(CV<13%),于37℃放置6天测定结果无明显差异,与小鼠中和试验法、英国Biding Site酶联试剂有良好的一致性。试验证明所研制的试剂盒适用于破伤风免疫血浆中的破伤风抗体效价定量检测。  相似文献   

10.
目的对兰州生物制品研究所有限责任公司研制的鼠疫菌F1抗体酶联免疫诊断试剂盒和鼠疫菌F1抗原酶联免疫诊断试剂盒进行临床应用评价。方法采用双抗原/抗体夹心酶联免疫吸附试验(ELISA)、间接血球凝集试验(IHA)、胶体金免疫层析试验(GICA)3种方法的诊断试剂对比检测云南省地方病防治所中心实验室保藏的和现场采集的血清样品和脏器样品,对血清样品做鼠疫菌F1抗体检测,对脏器样品做鼠疫菌F1抗原检测。结果在358份血清样品中,ELISA试剂检出F1抗体阳性52份(14.52%),IHA试剂检出阳性37份(10.34%),GICA试剂检出阳性45份(12.57%)。ELISA与IHA试剂的符合率为95.23%,与GICA试剂的符合率为96.92%。经统计学χ2检验,ELISA试剂检出F1抗体阳性率高于IHA试剂(χ2=11.53,P=0.000 7),与GICA试剂检出的差异无统计学意义(χ2=3.27,P=0.070 4)。进一步分析滴度差值频数,ELISA试剂检测人血清的敏感性高于IHA试剂的样品占87.5%。在117份脏器样品中,3种试剂均检出F1抗原阳性15份(12.82%),符合率100%。滴度差值频数比较,ELISA试剂检测敏感性高于反向间接血球凝集试验(RIHA)试剂的样品为78.57%。结论兰州生物制品研究所有限责任公司研制的鼠疫菌F1抗体酶联免疫诊断试剂盒和鼠疫菌F1抗原酶联免疫诊断试剂盒性质特异,其敏感性优于IHA试剂盒和GICA试剂条,值得在鼠疫的监测和快速诊断中推广应用。  相似文献   

11.
Oligonucleotide reagents bearing aromatic azido groups of different structures were shown to be suitable for nucleoside specific photomodification of nucleic acids. Modification of the pentadecanucleotide targets d(TAAGTGGAGTTTGGC), d(TAAGTGGAAAAAAAA), d(TAAGTGGACCCCCCC) and d(TAAGTGGATTTTTTT) was investigated with reagents d(UCH2OCH2CH2NHCORCCACTT) carrying a photoactive group R(R1-n-azidotetrafluorophenyl-reagent (I), R2-2-nitro-5-azidophenyl-reagent (II) and R3-n-azidophenyl-reagent (III)) at C-5-modified deoxyuridine. Photomodification did not exceed 5% for the targets in case of reagent (III); the modification extent was 25-50% depending on the target sequence for reagent (II); reagent (I) with perfluoro azido group was the most effective, that provided 60-70% of modification. Reagents (I) and (II) were found to be sensitive to the nucleoside sequence of the target: the most vulnerable sites for reagent (I) and (II) were guanine and cytosine residues, respectively. These bases were modified predominantly when being adjacent to the addressed site of the target.  相似文献   

12.
A new type of alkylating derivatives of oligonucleotides with 4(N-methyl-N-2-chloroethylamino)benzyl (RCl) group at C-5 of deoxyuridine with a high extent of the target modification was prepared. The synthesized reagents d(ULNHRClCCACTT), where L = CH2 (Ia), CH2OCH2CH2 (Ib) and CH2NHCOCH2CH2 (Ic), proved to effectively (80-90%) modify the oligonucleotide d(TAAGTGGAGTTTGGC). The reagents (Ia) and (Ib) alkylate G6, G7 and G9 positions, while the reagent (Ic) modifies predominantly G9.  相似文献   

13.
T Ueda  H Yamada  M Hirata  T Imoto 《Biochemistry》1985,24(22):6316-6322
Hen egg white lysozyme was treated at pH 5.5 with four bifunctional reagents, bis(bromoacetamide) derivatives [BrCH2CONH(CH2)nNHCOCH2Br, 1-n, n = 0, 2, 4, and 6], to alkylate His-15 monofunctionally. The excess bifunctional reagent was then removed, and the pH was raised to 9.0 to allow the other end of the reagent molecule to react. The shortest reagent (1-0) gave no intramolecularly cross-linked lysozyme derivative but only histidine-15-modified lysozyme monomer and intermolecularly cross-linked lysozyme dimer. However, the reagents with longer arms (1-2, 1-4, and 1-6) gave lysozyme derivatives cross-linked intramolecularly between the nitrogen at epsilon 2 of His-15 and the epsilon-amino group of Lys-1 without formation of any other intramolecularly cross-linked lysozyme derivative. These results are consistent with our previous proposal that lysozyme has a small hydrophobic pocket that binds small molecules in the direction from His-15 to Lys-1 [Yamada, H., Uozumi, F., Ishikawa, A., & Imoto, T. (1984) J. Biochem. (Tokyo) 95, 503-510]. The thermal stabilities of three cross-linked lysozymes thus obtained were investigated in 0.1 M acetate buffer containing 3 M guanidine hydrochloride at pH 5.5. All derivatives were stabilized but to different degrees. The derivative cross-linked with 1-4 was most stabilized (2.3 kcal/mol), but the derivatives cross-linked with the reagents both shorter (1-2) and longer (1-6) than 1-4 were less stabilized (both 1.6 kcal/mol).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
A system is described for freeze drying and storage of reagents (antisera) used in cattle blood typing tests. Reagents were freeze-dried in evacuated bottles at the desired dilution for rapid reconstitution to use in test procedures. Reagents not in current use were dried in bulk lots and stored in polyethylene film bags. All freeze drying procedures were performed with readily available commercial equipment. A computer program was developed to produce a current inventory of reagent supplies and projections of the number of samples which can be typed.  相似文献   

15.
Divergent pathways are disclosed in the activation of 2-O-benzyl-1-hydroxy sugars by a reagent combination of CBr4 and Ph3P, all of which afford one-pot alpha-glycosylation methods. When this reagent is used in CH2Cl2, the 1-hydroxy sugar is converted to the alpha-glycosyl bromide in a conventional way and leads to the one-pot alpha-glycosylation method based on a halide ion-catalytic mechanism. In either DMF or a mixture of DMF and CHCl3, however, alternative alpha-glycosyl species are generated. From the 1H and 13C NMR study of the products, as well as the reactions using Vilsmeier reagents [(CH3)2N+=CHX]X- (X=Br and Cl), these were identified as cationic alpha-glycopyranosyl imidates having either Br- or Cl- counter ion. The cationic alpha-glycosyl imidate (Br-), derived specifically in the presence of DMF, is more reactive than the alpha-glycosyl bromide and thus is responsible for the accelerated one-pot alpha-glycosylation. The one-pot alpha-glycosylation methodology performed in DMF was assessed also with different types of acceptor substrates including tertiary alcohols and an anomeric mixture of 1-OH sugars.  相似文献   

16.
Efficiency of the intracomplex alkylation of octadecadeoxyribonucleotide d(pC5A8C5) (target) by Rp- and Sp-individual diastereomers of the methylphosphonate octathymidylate 4-(N-methyl-N-2-chloroethylamino)benzyl phosphoramide (-pNHCH2RCl) derivatives bearing an additional N-(2-hydroxyethyl)phenazinium residue (phn), viz. ClRCH2NHpTp.(TpTp)3TpNH(CH2)2NHPhn (I) and PhnNH(CH2)2NHpTp(TpTp)3TpNHCH2RCl (II) (p = -OP(O) (CH3)O-), has been investigated. Stabilisation of the complementary complex formed by the target oligonucleotide and methylphosphonate oligonucleotide derivatives by the Phn group considerably rose the efficiency of the intracomplex alkylation of the target as compared with alkylation by reagents without Phn. RP-isomeric derivatives of (I) and (II) proved to be the most effective alkylating reagents. Specificity of alkylation of nucleic acid target by reagents (I) and (II) is studied.  相似文献   

17.
A series of thiol-specific cross-linking reagents were prepared for studying the kinetics of cross-linking between SH1 (Cys(707)) and SH2 (Cys(697)) in rabbit skeletal muscle myosin subfragment 1. The reagents were of the type RSS(CH(2))(n)()SSR, with R = 3-carboxy-4-nitrophenyl and n = 3, 6, 7, 8, 9, 10, and 12, spanning distances from 9 to 20 A. The reactions were monitored spectrophotometrically by measuring the release of 2-nitro-5-thiobenzoate. Reaction rates for modification of SH1 (k(1)) and for cross-linking (k(2)) were measured by the decrease of the K(+)(EDTA)-ATPase activity and the decrease of the Ca(2+)-ATPase activity, respectively, and corrected for the different reactivities of C(n). Cross-linking rates in the presence and absence of MgADP showed similar dependence on the length of the reagents: While the cross-linking rates for n = 3 or n = 6 were close to those for n = 0 (Ellman's reagent), those for n = 7 and 8 were significantly increased. Thus the distance between SH1 and SH2 appears to be equal in both states and can be estimated as >/=15 A, based on the length of the reagent with n = 8 in stretched conformation. Under rigor conditions, reactivity of SH1 differed significantly from that in the presence of MgADP, presumably because of shielding through a lipophilic domain. Similarly, the cross-linking rates k(2) for C(3), C(6), and C(7) in the absence of MgADP were ca. 15 times lower than in the presence of MgADP, suggesting a change in the structure of the SH2 region that depends on nucleotide binding. The results are discussed in terms of recent X-ray structures of S1 and S1-MgADP [Rayment et al. (1993) Science 261, 50-58; Gulick et al. (1997) Biochemistry 36, 11619-11628].  相似文献   

18.
An attempt has been made to extend to the cysteinyl exopeptidases cathepsins H and C affinity-labelling approaches shown to be effective with cysteinyl endopeptidases such as cathepsins B and L and the calcium-activated proteinase. This involved the preparation of amino acid and dipeptide derivatives with unblocked N-termini to satisfy the aminopeptidase and dipeptidyl aminopeptidase characteristics of cathepsins H and C respectively. For covalent reactivity, the possibilities examined included diazomethanes (-CHN2), fluoromethanes (-CH2F) and dimethylsulphonium salt [-CH2S+(CH3)2]. A dipeptidylfluoromethane with a free amino group could not be prepared, perhaps due to inherent instability. Cathepsin H was inactivated by 1 microM-H2N-Phe-CH2F (the 'H2N' indicates a free unblocked amino group) (k2 = 1878 M-1.s-1); this reagent was without effect on cathepsins C and B, even at 100-fold this concentration. Analogous selectivity was shown by H2N-Ser(OBzl)-CHN2 and H2N-Phe-CH2S+(CH3)2, members of other classes of covalently binding reagents. For cathepsin C the dipeptide derivatives H2N-Gly-Phe-CHN2 and H2N-Phe-Ala-CH2S+(CH3)2 caused rapid inactivation near 10(-7) M. Higher concentrations inactivated cathepsins H and B, but the rates were slower by two to three orders of magnitude than for cathepsin C.  相似文献   

19.
The effect of intrathecal injections of dynorphin1-8 (DYN1-8), dynorphin1-13 (DYN1-13), and a putative kappa agonist, U50,488 was tested in the rat tail-flick test. DYN1-8 and DYN1-13 (5, 10, 20 micrograms) produced a dose-related biphasic antinociceptive response consisting of an initial and a delayed response. Injection of U50,488 (20, 40 60 micrograms) produced a monophasic response. The antinociceptive effect of DYN1-8 (5, 10, 20 micrograms) and DYN1-13 (20 micrograms), was present 24 h postintrathecal injection. Pretreatment with systemic naloxone (2 mg/kg s.c.) attenuated the delayed response, but not the initial response induced by DYN1-8 and DYN1-13. The initial response was attenuated by pretreatment with intrathecal naloxone at a dose of 0.5 and 2.0 micrograms. The antinociceptive effect of U50,488 (20, 60 micrograms) was not affected by pretreatment with 2.0 micrograms intrathecal naloxone, but was significantly reduced by 4 micrograms of the antagonist. Both DYN1-8 and DYN1-13 (5 micrograms) augmented the antinociceptive effect of intrathecally administered morphine (5, 10 micrograms). Intrathecal injection of DYN1-8 (5, 10, 20 micrograms), DYN1-13 (5 micrograms), and morphine (10 micrograms) reduced the spontaneous output of urine measured at 2 and 24 h postintrathecal injection. A similar injection of U50,488 (20 micrograms) had no significant action on the urinary output. The results show that long and short dynorphin fragments have a comparable activity and the spinal antinociceptive actions of dynorphin are sensitive to low doses of intrathecal naloxone. The activity profile of spinally administered dynorphins differs from that of the kappa agonist U50,488.  相似文献   

20.
Dynorphin 1-17 (DYN 1-17) is biotransformed rapidly to a range of fragments in rodent inflamed tissue with dynorphin 3-14 (DYN 3-14) being the most stable and prevalent. DYN 1-17 has been shown previously to be involved in the regulation of inflammatory response following tissue injury, in which the biotransformation fragments of DYN 1-17 may possess similar features. This study investigated the effects of DYN 3-14 on lipopolysaccharide (LPS)-induced nuclear factor-kappaB/p65 (NF-κB/p65) nuclear translocation and the release of pro-inflammatory cytokines interleukin-1beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) in differentiated THP-1 cells. Treatment with DYN 3-14 (10 nM) resulted in 35% inhibition of the LPS-induced nuclear translocation of NF-κB/p65. Furthermore, DYN 3-14 modulated both IL-1β and TNF-α release; inhibiting IL-1β and paradoxically augmenting TNF-α release in a concentration-independent manner. A number of opioids have been implicated in the modulation of the toll-like receptor 4 (TLR4), highlighting the complexity of their immunomodulatory effects. To determine whether DYN 3-14 modulates TLR4, HEK-Blue™hTLR4 cells were stimulated with LPS in the presence of DYN 3-14. DYN 3-14 (10 μM) inhibited TLR4 activation in a concentration-dependent fashion by suppressing the LPS signals around 300-fold lower than LPS-RS, a potent TLR4 antagonist. These findings indicate that DYN 3-14 is a potential TLR4 antagonist that alters cellular signaling in response to LPS and cytokine release, implicating a role for biotransformed endogenous opioid peptides in immunomodulation.  相似文献   

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