RPG1: an essential gene of Saccharomyces cerevisiae encoding a 110-kDa protein required for passage through the G1 phase

In Saccharomyces cerevisiae cells a number of genes are required for progression through, or else to pass beyond, the G₁ phase. We characterized a novel gene, RPG1, which is also involved in this phase. RPG1 is an essential gene encoding a 110-kDa evolutionarily conserved protein. Elutriated or α-factor-synchronized cells of the rpg1-1 temperature-sensitive mutant were arrested in the first cell cycle when shifted to a non-permissive temperature. The cells remained unbudded and neither grew nor duplicated DNA. rpg1-1 cells synchronized in S phase completed mitosis and arrested as unseparated G₁ cells after a shift to a non-permissive temperature. Similarly, the asynchronous rpg1-1 cells accumulated in G₁ at the non-permissive temperature, but mother and daughter cells did not separate. A bulk of Calcofluor-stained material was localized in the region adjacent to the cell septum. Our data show that Rpg1p is required for passage through the G₁ phase and may be involved in growth control. Data published recently indicate that Rpg1p exhibits significant sequence similarity to a subunit of the mammalian translation initiation factor 3. Received: 6 October 1997 / 8 November 1997     

Plasma protein binding of imipramine in patients with rheumatoid arthritis

Summary In 23 patients with rheumatoid arthritis the plasma protein binding of³H-imipramine and the plasma levels of 13 proteins were measured in order to examine the significance of the proteins for the binding of imipramine. The degree of³H-imipramine binding did not differ significantly from that in healthy controls. It was positively correlated with the concentrations of fibrinogen, ₁-acid-glycoprotein, ceruloplasmin, complement C3_c, haptoglobin and hemopexin. Erythrocyte sedimentation rate was also highly positively correlated with binding. The concentration of several of the proteins showed a significant covariation. The³H-imipramine binding was negatively correlated with the concentration of albumin and the latter was negatively correlated with some of the proteins mentioned-above. No correlation with the levels of apolipoproteins A and B was found. There appears to be more a qualitative than a quantitative change in³H-imipramine binding in patients with rheumatoid arthritis.     

高效液相色谱-串联质谱法测定蜂蜜中氯霉素、甲砜霉素、氟甲砜霉素及甲硝唑

目的 建立蜂蜜中氯霉素、甲砜霉素、氟甲砜霉素及甲硝唑残留的高效液相色谱-串联质谱同时测定方法。方法 以乙酸乙酯作为提取剂,经涡旋混匀提取后,氮吹至干,用5%甲醇水溶解,Oasis HLB固相萃取柱净化。经甲醇洗脱,洗脱液经45℃水浴氮吹至干,流动相涡旋溶解,上机测定。高效液相色谱分离、串联质谱检测,采用多离子反应监测（MRM）模式,内标法定量。结果 在优化条件下,4种抗生素浓度在0.1～5.0μg/L范围内,线性关系良好,相关系数（r）≥0.9953,方法检出限≤0.015μg/kg,不同基质中平均加标回收率为78.5%～95.1%,相对标准偏差（RSD）为2.8%～10.7%。结论 该方法快速、灵敏、准确,适用于蜂蜜中氯霉素、甲砜霉素、氟甲砜霉素及甲硝唑的同时测定。     

热力学模型对石油低压汽液平衡计算的适用性

以Maxwell-Bonnel图拟合式、对比态Antoine方程及Pitzer-Riedel关联式分别求算饱和蒸汽压P^0,并用RoultK值（K＝P^0／P）,计算窄留分K值。根据实测的中原、孤岛和克拉玛依石油馏分低压K值,考察上述三式,结果表明：对比态Antoine式预测精度是最好的,其温度预测绝对平均偏差为7．0℃,K值预测平均相对偏差为15．6％,其他两模型偏差均较大。     

固相萃取结合高效液相色谱法测定人体血浆中氟罗沙星的含量

建立固相萃取结合HPLC高效液相色谱法对人体血浆中的氟罗沙星含量进行检测,为氟罗沙星的体内血药浓度监测和人体药代动力学研究提供测定方法.血样经固相萃取法处理,HPLC-高效液相色谱紫外检测法测定,外标法定量.结果发现本文建立的方法血样处理简单、杂质少、干扰小.高、中、低浓度的平均回收率平均为92.78%,在氟罗沙星体内治疗浓度范围内,检测线性关系良好.日内误差与日间误差均低于10%,精密度和准确度都能满足药动学研究及血药浓度监测的要求.结果提示固相萃取结合HPLC高效液相色谱法测定血浆氟罗沙星浓度重复性好、干扰小,是一种较为理想的测量方法.     

夏商周断代工程的研究途径与阶段性成果

国家“九五”期间重点科技攻关计划项目“夏商周断代工程” ,经过200位专家学者前后5年的集体努力 ,已于2000年9月通过验收 ,同年11月公布了《夏商周断代工程1996-2000年阶段成果报告 (简本 )》。这一项目采取自然科学与人文社会科学多学科结合的研究途径 ,制定了《夏商周年表》 ,为我国古代夏商周这一重要历史时期的年代学提供了科学依据 ,使进一步探索中国古代文明起源及其早期发展有了可靠的基础。     

基于Heracles NEO超快速气相电子鼻麸炒白术炮制全过程气味变化识别研究

目的 建立麸炒白术Atractylodis Macrocephalae Rhizoma炮制全过程的定性判别模型,筛选出可以表征麸炒白术不同炮制程度的气味成分。方法 制备麸炒白术饮片,不同时间点取样进行分析。采用Heracles NEO超快速气相电子鼻采集气味图谱,与Arochembase数据库对比得到气味成分信息,结合峰面积分析气味成分的变化规律并进行化学计量学分析。结果 通过判别因子分析（discriminant factor analysis,DFA）、正交偏最小二乘-判别分析（orthogonal partial least squaresdiscriminant analysis,OPLS-DA）、层次聚类分析（hierarchical cluster analysis,HCA）等将麸炒白术炮制全过程样品成功分为4类：生品、炮制不及、炮制成品和炮制太过。在炮制过程中,3-甲基十五烷、十二烷基丙酸酯、正辛基环己烷、1,3-二硝基苯、8-甲基十五烷5个气味成分的峰面积占比较高,其中1,3-二硝基苯在炮制全过程中峰面积呈降低趋势;3-甲基十五烷从炮制不及到炮制成品的过程中峰面积呈增加...     

大黄-黄芪组分自微乳的制备及在体肠吸收特性研究

目的 研究大黄-黄芪多组分自微乳的处方与制备工艺,评价制剂质量,并考察其大鼠肠吸收特性。方法 通过溶解度实验、油相与乳化剂和助乳化剂配伍实验及伪三元相图的绘制,筛选出最优处方组成;并从自微乳的外观、形态、粒径、稳定性等方面对自微乳进行评价。通过大鼠在体单向肠灌流实验考察自微乳的肠吸收特性。结果 自微乳处方中油相为辛酸癸酸单双甘油酯、乳化剂为聚氧乙烯蓖麻油35、助乳化剂为乙二醇。在微乳形成区选择各辅料用量,采用适宜方法加入大黄总蒽醌及黄芪总皂苷制得的组分自微乳,外观均一透明,加水分散后形成黄色乳光的微乳液,透射电镜显微镜（transmission electron microscopy,TEM）下观察到微乳分散均匀,无黏连,呈大小均一圆球形乳滴;平均粒径为（33.01±0.12）nm、多分散指数（polydispersion index,PDI）为0.10±0.02、电位为（-10.10±1.00）m V;自微乳中大黄总蒽醌和黄芪总皂苷质量分数分别为6.29、8.80 mg/g。自微乳中大黄总蒽醌在十二指肠、空肠段的吸收速率常数（Ka）及表观吸收系数（Papp）较回肠段均有显著提高;黄芪...     

中医外治技术联合快速康复外科理念对肝胆外科术后患者的临床疗效

目的:探讨中医外治技术联合快速康复外科(ERAS)理念促进肝胆外科患者康复的临床疗效。方法:选择于2018 年8 月—2020 年10 月在我科行腹腔镜手术的患者308 例,随机分为外治组156 例,对照组152 例。对照组行腹腔镜手术+ERAS 理念,外治组在前者基础上加用中医外治技术,比较两组患者在术后肠鸣音恢复、肛门首次排气及排便时间、疼痛评分、住院天数、相关并发症等方面的差异。结果:外治组术后肠鸣音恢复、肛门首次排气排便时间均短于对照组(P <0.05),术后疼痛评分低于对照组(P <0.05),行肝脏手术及胰腺手术患者的住院时间均短于对照组(P <0.05)。但两组相关并发症发生率差异无统计学意义(P <0.05)。结论:中医外治技术联合ERAS 理念在肝胆外科围手术期的应用能减轻术后患者的疼痛,促进胃肠道功能的恢复,缩短住院时间,值得临床推广应用。