高效液相色谱法测定游泳池水中的尿素

目的建立使用HPLC测定游泳池水中尿素的含量。方法使用超纯水为流动相,测定波长190 nm,柱温30℃,流速1.0mL/min,进样量20？L,保留时间定性,峰高定量。结果水中尿素在0.3mg/L~40 mg/L时与峰高成良好的线性关系(Y=2.9175X+0.7399,r=0.9998),检出限为0.3mg/L,回收率99.10~102.24%,精密度RSD为0.34~0.74%。结论本方法操作简便,分析速度快,精密度、回收率均令人满意,满足实际检测需要。     

高效液相色谱法测定川芎中阿魏酸的含量

目的 以川芎常见的阿魏酸为研究对象,建立液相色谱测定方法,为监管药物安全提供技术支持.方法 川芎样品加水研磨并过滤,分别取以上样品的上清液或滤过液;川芎样品直接过0.45μm滤膜后分析.色谱检测条件为:Cis色谱柱,流动相为5∶95的甲醇,5mmol/L三羟甲基氨基甲烷缓冲溶液(pH4.5),流速为1.2ml/min,紫外检测波长205nm,测定结果与国家标准方法进行了比对.结果 对同一川芎样品进行5次测量,其变异系数均小于2%,加标回收率为98.6%.结论 本文首次采用离子对色谱法同时检测川芎中阿魏酸的含量,不需衍生,方法快速、简便,在药物检验中具有实际应用价值.     

超高效液相色谱法测定紫杉醇注射液中的有关物质

目的 建立测定紫杉醇注射液有关物质的超高效液相色谱法。方法 采用Thermo Hypersil GOLD C₍18色谱柱(100 mm×2.1 mm,1.9μm),以水和乙腈为流动相,流速为0.6 ml/min,检测波长227 nm,采用主成分自身对照法测定有关物质含量。结果 在15min内紫杉醇与相邻杂质以及各杂质间分离度均满足要求。检出限和定量限分别为0.053 ng和0.11 ng,质量浓度在1.21～4.85μg/ml范围内线性关系良好,加样回收率为99.84%,RSD为2.80%(n=9)。两批市售样品均检出杂质Ⅰ和杂质Ⅲ,杂质含量均符合Ch P2020规定。结论 本文建立的超高液相色谱法能够准确、快速完成紫杉醇注射液有关物质测定。     

快速简便高效液相色谱法测定血中环孢霉素A

用反相高效液相色谱法测定血中环孢霉素A浓度。该法具有灵敏、准确、快速、经济等特点。环孢霉素A和内标环孢霉素C的保留时间分别为8.6分和7.6分。样品萃取过程不需进行酸、碱处理。标准血样提取的最低检测浓度为10μg/L血浆。经提取的标准曲线相关系数为0.9999。方法回收率为97％,日内日问测定变异系数CV,均小于5％。     

反相高效液相色谱法测定血清中的5-羟色胺

建立了一种简便、快速测定血清中5-羟色胺的反相高效液相分析方法。采用的色谱柱为Bondapak C18不锈钢柱(5μm,250mm×4.6mmi.d.),流动相为:甲醇—水—乙酸(70:30:0.1 V/V),流速:1ml/min,荧光监测器,激发波长278nm,发射波长333 nm。结果表明:该方法线性关系良好(r=0.99992),5-羟色胺测定的线性范围为0.10~2.00μg/mL,最低检测限为0.02μg/mL(S/N=3)。5-羟色胺在血清样品中的加标回收率为92.37%~100.12%。该测定方法结果准确,可用于临床研究。     

微透析-高效液相色谱法测定大鼠脑脊液中4种氨基酸的含量测定

目的： 通过对大鼠脑透析液中氨基酸的含量测定,为在体氨基酸分析建立方法。方法： 利用微透析技术抽取麻醉下大鼠脑脊液，运用OPA柱前衍生法处理样品，再用高效液相二元梯度洗脱色谱法，BDSC18柱（Hypersil，4.6 mm×250.0 mm，5 μm），荧光检测脑脊液中谷氨酸、天门冬氨酸、γ-氨基丁酸、牛磺酸等4种氨基酸的含量。结果： 该体系可在30 min内对脑脊液中4种氨基酸实现良好的分离，4种氨基酸在0.625-10 μmol/L浓度范围内与色谱峰面积线性关系良好，保留时间分别是天门冬氨酸4.392 min、谷氨酸5.592 min、牛磺酸13.625 min、γ-氨基丁酸14.833 min。结论: 本方法准确、灵敏、方便、重复性好，可用于微透析样品中氨基酸的含量测定。     

高效液相色谱法测定狼疮性肾炎患儿血浆中环磷酰胺的含量

目的 建立测定狼疮性肾炎(LN)患儿血浆中环磷酰胺含量的高效液相色谱(HPLC)方法,为制订个体化治疗方案提供依据.方法 色谱柱为Hypersil ODS-2 C18柱,流动相为乙腈-水(体积比为30:70),流速为1.0 ml/min,柱温为30℃,检测波长为195 nm,进样量为20μl.以异环磷酰胺为内标,血浆样品经甲醇沉淀蛋白、离心取上清液进样检测.结果 血浆中环磷酰胺的质量浓度在0.5～20.0 mg/L范围内,环磷酰胺与内标的峰面积比呈良好的线性(r=0.9994),最低检出限为0.1 mg/L;日内、日间精密度和稳定性实验的相对标准偏差(RSD)均＜8％;加样回收率为100.60％～101.05％,结果满意.结论 该法简便、快速、准确、重现性好,可用于LN患儿血浆中环磷酰胺的含量测定及免疫抑制治疗的临床药学监护.     

反相高效液相色谱法测定兔血清中5-氟尿嘧啶的浓度

目的应用反相高效液相色谱法测定兔血清中5-氟尿嘧啶的浓度。方法兔血清样品经乙酸乙酯/异丙醇(84/16)萃取后,水浴氮气吹干,流动相定容后进样。色谱柱为kromasil-C18柱(250mm×4.6mm,5μm),流动相为20mM醋酸铵/乙腈(体积比98.2∶1.8,pH8.05),流速0.8mL/min,紫外检测波长为270nm。结果5-氟尿嘧啶在5～80μg/L浓度范围内呈良好的线性关系。10、20、40μg/L三个浓度的批内RSD分别为11.6%、5.6%、5.4%;批间RSD分别为12.8%、2.7%、6.2%;平均回收率分别为106.7±11.7%、98.0±5.3%、99.3±5.3%。结论本方法可靠、重复性好,具有特异性强、灵敏、精密度与准确度高等特点,满足5-氟尿嘧啶药代动力学研究的要求。     

高效液相色谱法测定人红细胞膜脂肪酸含量及组成

本文采用高效液相色谱法测定了４２例正常成人红细胞膜脂肪酸（ＦＡ）含量及组成。结果表明：该法分离效果好、定量准确。重复性变异系数平均５．５％，回收率平均９４．７％。人红细胞膜主要由廿二碳六烯酸（Ｃ２２６）、花生四烯酸（Ｃ２０４）、亚油酸（Ｃ１８２）、软脂酸（Ｃ１６０）、油酸（Ｃ１８１）和硬脂酸（Ｃ１８０）等六种ＦＡ组成，其中花生四烯酸含量最高，其次为硬脂酸。不饱和脂肪酸占７１．６％。     

高效液相色谱法测定独角莲膏中连翘苷的含量

目的建立用高效液相色谱（HPLC）测定独角莲膏中连翘苷的含量的方法。方法采用Hypersil ODS2（5．0×200mm）色谱柱,乙腈与水（24：76）的混合液为流动相;流速为1．0ml／min,柱温为30℃,检测波长227ml。结果连翘苷进样量在0．1424μg～0．712μg时线性良好（r=0．99998）,平均回收率为99．22％,RSD为2．16％。结论该方法准确、简便、重现性好、专属性强,可用于该产品中连翘苷含量的测定。     

A comparative study of the properties of different distribution curves

The maximum, points of inflection and the derived peak width are enumerated for a Poisson, a Gauss and a Schulz‐Flory distribution. Starting with a (not necessarily normalized) number distribution the respective molar mass and hyper distributions are derived and the extrema and the peak width are determined as well. It turned out, that Poisson and (narrow, D < 1.1) Gauss distributions can be characterized by the fact that the peak width is an invariant quantity with respect to the number, molar mass and hyper distribution, whereas the peak width changes considerably for a Schulz‐Flory distribution. In order to demonstrate the theoretical results commercial polymer standards (prepared by anionic polymerization) were measured by size exclusion chromatography and the constancy of the peak width is demonstrated but the peak widths exceeded by far the theoretically expected values. The influence of axial broadening in size exclusion chromatography is discussed in this context and a simple correction procedure is presented for an ideal Poisson distribution. On the other hand, polymers prepared by stationary radical polymerization displayed a very marked deviation from an invariant peak width, as derived theoretically. It is demonstrated that the location of the peak maximum in the molar mass and the hyper distribution is identical with M _n and M _w, respectively.

Comparison of the peak width of molar mass distributions: Poisson, Gauss with polydispersity 1.1 and Schulz‐Flory with k = 1 and 2, respectively.     

Determination of the molecular weight distribution of the PEGylated bovine hemoglobin (PEG-bHb)

The method to determine the average molecular weight and distribution of molecular weight of the PEGylated hemoglobin (PEG-bHb) and their molecular weight of polypeptides in PEG-bHb with UV absorbance (UV), light scattering (LS) and refractive index (RI) detectors is described in this paper. The results indicate that when molar ratio of PEG to hemoglobin is 7:1, the average molecular weight of PEG-bHb (M(CP) is 95 kDa, the average molecular weigh of protein moiety in PEG-bHb (M(P)) is 68 kDa, and their distribution is from 48-157 kDa and 44-121 kDa, respectively; when the molar ratio is 10:1, the M(CP) is 106 kDa, the M(P) is 70kDa, and their distribution is from 56-216kDa, 49-135kDa, respectively; when the molar ratio is 13:1, the M(CP) is 73kDa, and their distribution is from 81-272 kDa and 41-144 kDa, respectively. It has been proved that this method is a simple and reliable way for the determination of average molecular weight and distribution of molecular weight of PEGlyted hemoglobin. This experiment also suggests that there exists not only aggregation in the frontal of elution peak of PEG-bHb, but dissociation of tetramer of hemoglobin into dimmer in the tail of elution peak, and the degree of aggregation is depended on the molar ratio of PEG to hemoglobin due to the present of diol PEG and the dissociation is dependant on the concentration of hemoglobin.     

Bacterial adhesion to polyurethane surfaces in the presence of pre-adsorbed high molecular weight kininogen

The factors which affect the adherence of a bacteria cell to the surface of a biomaterial include the surface chemistry of the cell and material, as well as the composition of the adsorbed protein layer when the biomaterial is exposed to circulating blood. In an effort to better understand the mechanisms by which bacteria adhere to such surfaces, and specifically to determine the effects of high molecular weight kininogen on bacterial adhesion, experiments were performed in which the attachment of Staphylococcus aureus was directly observed on glass and on a series of functionalized polyurethanes. These surfaces had been pre-adsorbed with various concentrations of high molecular weight kininogen and fibrinogen. Attachment was observed using a radial flow chamber, in which shear stress varied inversely with radial distance. Protein adsorption studies were also performed using ¹²⁵I labeled fibrinogen to investigate the relationship between surface chemistry, protein adsorption, and bacterial attachment. Bacterial attachment was significantly decreased when the glass surface was pre-adsorbed with high molecular weight kininogen-either alone, or following adsorption of fibrinogen. High molecular weight kininogen thus exhibited anti-adhesive effects. On polyurethane surfaces pre-adsorbed with fibrinogen, kininogen, and albumin, the highest bacterial attachment was found on the base polyurethane, while significant decreases were seen on the hydrophilic polyurethanes. In addition, it was found that the surface with the least bacterial attachment and fibrinogen deposition was the polyurethane with pendant phosphonate groups.     

EPDM Synthesis by the Ziegler Catalyst Cp*TiMe3/B(C6F5)3

The utilization of the Ziegler catalyst Cp*TiMe₃/B(C₆F₅)₃ for the terpolymerization of ethylene, propylene and 5‐ethylidene‐2‐norbornene to give EPDM is investigated, and the major factors affecting yields, molecular weights, molecular weight distributions and compositional distributions of the EPDM polymers are assessed. High molecular weight polymers with narrow molecular weight distributions are obtained at ˜18°C.     

宫颈癌患者手术前后血清SCC、CYFRA21-1和CA125检测的临床意义

本文对宫颈癌患者手术治疗前后血清鳞状细胞癌抗原（SCC）、细胞角蛋白片段19（CYFRA21-1）和CA125进行检测,现将结果报告如下。     

Preparation and hemostatic property of low molecular weight silk fibroin

Effective hemorrhage control becomes increasingly significant in today’s military and civilian trauma, while the topical hemostats currently available in market still have various disadvantages. In this study, three low molecular weight silk fibroins (LMSF) were prepared through hydrolysis of silk fibroin in a ternary solvent system of CaCl₂/H₂O/EtOH solution at different hydrolysis temperatures. Fourier transform infrared spectroscopy analysis showed that the content of β sheet structure in the LMSF decreased with the increase in hydrolysis temperature. The results of thromboelastographic and activated partial thromboplastin time methods showed that the LMSF hydrolyzed at 50?°C can significantly strengthen the coagulation in blood and activate the intrinsic pathway of coagulation cascade. In the murine hepatic injury model, the LMSF hydrolyzed at 50?°C can promote the blood clotting and decrease the blood loss and bleeding time. Based on these results, it can be suggested that the developed LMSF has the excellent hemostatic effect and may be a promising material in clinical hemostatic application.     

Renal processing of low molecular weight proteins

Previous renal clearance studies provided quantitative data concerning renal reabsorption of proteins while the simultaneous processes of renal accumulation and degradation remain, to a great extent, insufficiently investigated. Thus, it was the aim of this study to measure renal reabsorption of egg-white lysozyme at various lysozyme concentrations and to relate the corresponding accumulation and degradation of lysozyme to the lysozyme transport rates in intact rats and isolated perfused rat kidneys. Lysozyme (with¹²⁵I-lysozyme in certain experiments), was continuously infused i.v. or added to the perfusate to achieve plasma (or perfusate) concentrations of lysozyme (P_LY) of approximately 50, 500 or 1000 mg·l^–1 for periods of time varying between 3 and 120 or 150 min. Clearances of inulin and lysozyme or the total content of radioactivity and the trichloroacetic acid (TCA)-soluble radioactivity in the kidney tissue were determined at the end of clearance or accumulation periods. Additionally the perfusate concentration of the metabolite tyrosine was measured by high performance liquid chromatography (HPLC).The reabsorption rates of lysozyme (T_LY) were concentration-dependent in both intact rats and isolated perfused rat kidney. After 25 min of lysozyme infusion, the lysozyme reabsorption rates amounted to 37, 245 and 331 g·min^–1·g^–1 kidney at the above lysozyme concentrations. After the same infusion time, the accumulation rates of lysozyme were 8, 59 and 118 g·min^–1·g^–1 kidney. The difference between the transport rate and accumulation rate should represent the renal degradation rate of lysozyme. The renal accumulation and degradation of lysozyme appeared to increase in a time- and concentration-dependent manner. The renal lysozyme degradation is of limited capacity as shown by measuring directly the release of the amino acid tyrosine by using HPLC. Renal degradation of lysozyme was almost totally inhibited by gentamicin in the presence of significant transport of lysozyme.The results of this study also demonstrate the ability of the rat kidney to reabsorb and accumulate large amounts of the cationic low molecular weight protein lysozyme without ultrastructural changes at plasma concentrations of lysozyme as high as 500 mg·l^–1. Transmission electron microscopy indicated an increase in the number of endocytic vesicles and lysosomes at 1000 mg·l^–1 plasma concentration of lysozyme after a 30 min infusion.     

Successful pregnancy with low molecular weight heparin in two women with recurrent miscarriage of unknown etiology

We report here two cases of recurrent miscarriages that were successfully treated with continuous intravenous administration of low molecular weight heparin (LMWH). One patient experienced 11 spontaneous abortions, and the other eight abortions. Previous treatments including prednisone, aspirin and mononuclear-cell immunization were all unsuccessful. They were negative for anticardiolipin antibodies and lupus anticoagulant, and had no inherited thrombophilic disorder. Intravenous administration of LMWH, 4800 units of dalteparin, was started as soon as the conception was confirmed, and was continued until 34 weeks of gestation. They were delivered of live born infants.     

超高分子量聚乙烯在人工关节假体中的应用及评价方法

本文通过查阅人工关节领域的相关文献、技术标准、产品指导原则等对超高分子量聚乙烯在人工关节中的应用及评价方法进行了总结。在假体设计开发时,需综合考虑假体设计和影响产品临床使用的风险因素,全面评价产品的材料性能、锁定强度、疲劳性能、体外磨损、生物相容性等,以确保产品的安全有效性。     

Conformation and sequence dependent antigenic determinants in human low molecular weight kininogen

Conformation and sequence-dependent antigenic determinants were investigated using a kinin-free low molecular weight kininogen isolated from Cohn's plasma fraction IV. This antigen contains the determinants of the apparently intact heavy chain common to the high molecular weight and low molecular weight kininogens. Straightforward reduction and carboxymethylation destroyed the immunoreactivity of this molecule. Antiserum prepared against the reduced protein recognized both reduced and unreduced antigen showing the presence of both types of antigenic determinant. The corresponding antibodies were separated using immunoadsorbent columns. As shown by the higher avidity of the antibodies, the conformation-dependent determinants dominate the antigenic structure.