氨基糖苷类抗生素的发展历程

抗生素的定义，首先来自于20世纪40年代链霉素的发现。在随后的几十年中，其他氨基糖苷类抗生素家族被大量发现并广泛应用，一度成为抗革兰阴性菌感染的首选抗生素。但由于其毒副作用较大，并且细菌对其不断产生耐药性，加上其他结构类别的新型抗生素的不断发现，使其一度几乎退出历史舞台。然而随着多重耐药细菌引起的感染率急剧上升，人们开始关注氨基糖苷类抗生素作为几种重要的治疗革兰阴性病原体的方案之一，并且发掘了其在治疗感染性疾病、艾滋病和遗传性疾病的潜力，使这个“老牌”抗生素重焕生机。     

海口地区2000年临床分离菌耐药性监测

目的：监测海口地区临床分离菌对抗菌药物的耐药状况。方法：采用VITEK微生物自动分析仪测定药敏。结果：2000年共收集临床分离菌1399株，革兰阳性球菌426株（30．5％），革兰阴性杆菌973株（69．5％），以铜绿假单胞菌、大肠杆菌、金黄色葡萄球菌、肺炎克雷伯杆菌最多见，所监测的细菌总体耐药率比国内其他地区偏高，且出现万古霉素耐药的表皮葡萄球菌和粪肠球菌。结论：海口地区的细菌耐药严重，控制细菌耐药成为当务之急。     

通过原生质体融合获得青霉素高产菌株

采用两株分别带有不同抗药性标记的产黄青霉原生质体以1:1相混合,用30％的聚乙二醇(MW6000)原生质体融合处理。将混和物涂布在补给有两种药物同时存在的高渗性分离培养基上,培养后获得异核体菌落。洗下异核体分生孢于继续分离在补给有两种药物同时存在的分离培养基上,得到了同时带有两种抗性标记的重组体。纯化后,进行抗性稳定性和摇瓶效价的测定,将一株具有双重抗性、摇瓶发酵效价较高的菌株作出发菌株,经诱变因子处理后,获得了一株43u7c—57菌株,在摇瓶中效价比生产菌株平均提高4.94％,该菌株在40吨发酵罐试生产后,发酵效价平均提高4.4％,产量则平均增加12.15％。     

Pulsatility and resistance indices in intrarenal arteries of normal adults

In order to establish the normal range of values of Pulsatility (PI) and Resistance (RI) Indices in the intrarenal vasculature, a study of 50 healthy volunteers (23 males, 27 females), divided into five groups of 10 according to age, was performed with Duplex Doppler ultrasound. Both kidneys were examined in all individuals and, in 12, indices were also compared between upper and lower poles of both kidneys. In addition, repeat examinations were performed in nine subjects on three different days, in order to assess the reproducibility of the method. No differences were found in the mean values of both indices between males and females, upper and lower poles, right and left kidneys. A statistically significant increase (p < 0.01, unpaired t-test) was demonstrated when the oldest age group (7th decade) was compared to the youngest age group (3rd decade). The method appeared remarkably reproducible for RI (4.2–7%), with wider variation in the PI (9.5–22.7%).     

连续四年ICU病房院内感染病原菌的耐药性分析

目的 :了解我院重症监护病房 (ICU)院内感染病原菌的耐药性变化趋势。方法 :对我院 ICU2 0 0 0年 1月至 2 0 0 3年 12月院内感染的各类感染标本中分离的 74 1株病原菌加以整理分析 ,并按美国国家临床实验室标准委员会 (NCCL s)标准进行药敏试验 ,并对其耐药性进行分析。结果 :分离出的菌株以革兰阴性杆菌为主 ,其次是革兰阳性球菌、真菌 ,分别占 6 2 % ,2 9% ,9% ,感染部位以肺部最多 5 5 1株 (74 .4 % ) ,泌尿道感染 5 0株 (6 .7% ) ,引起败血症35株 (4.7% ) ,来自各种体液 (胸、腹水、胆汁 ) 5 2株 (7.0 % ) ,来自各种引流液和伤口分泌物 2 5株 (3.4 % ) ,静脉导管13株 (1.8% ) ,其他 15株 (2 .0 % )。革兰阴性杆菌以非发酵菌为主 ,其中铜绿假单胞菌 135株 (18.2 % )、嗜麦芽窄食单胞菌 38株 (5 .1% )、不动杆菌属 37株 (4.9% )及其他非发酵菌 5 7株 (7.7% ) ,其次大肠埃希菌 91株 (12 .3% )、肺炎克雷伯菌 5 3株 (7.2 % )、肠杆菌属 33株 (4.5 % )、其他肠杆菌科 17株 (2 .3% )。铜绿假单胞菌对亚胺培南的耐药率达 4 1.0 % ,呈多重耐药 ,阴沟肠杆菌对头孢他啶、氨曲南的耐药率达 6 0 .0 %、73.3% ,大肠埃希菌、肺炎克雷伯菌产超广谱β-内酰胺酶 (ESBL s)的发生率分别是 4 1.0 %、4 5 .0 % ,亚胺培南?     

238例复治肺结核病人耐药状况分析

目的 了解复治肺结核病人形成原因和耐药状况，分析结核病控制策略的效果。方法 分析1999年湖北省耐药监测入选238例复治涂阳培阳病例既往病史和耐药状况；药敏试验采用比例法，培养基中药物浓度分别为S 4μg/ml、H 0．2μg/ml、R 40μg/ml和E 2μg/ml；结果 总耐药率为44．5％，耐多药率为21．8％，在综合医院、乡镇卫生院和结防专业机构治疗造成的耐药率和耐多药率(含H和R)分别为56．4％、31．3％、46．3％和30．8％、15．0％、20．8％。结论 治疗不规范是导致耐药率和耐多药率升高的原因，建议加强结核病人归口、化疗和全程督导管理，进一步完善结核病控制策略，减少复治病例和耐药的产生。     

重庆地区近五年小儿菌痢菌群变化及耐药状况

我院近五年收治小儿菌痢２０３１例，培养分离出痢杆菌９８５珠，其中福氏９０４株，占９１．７８％，全部为福氏２ａ型，宋内氏８１株，占８．２２％。常见抗菌药物如氨苄青霉素、氯霉素、痢特灵的耐药性均达９５％以上，庆大霉素、吡哌酸、氟哌酸、丁胺卡那霉素、卡那霉素的耐药性逐年升高；头孢噻肟、环丙沙星耐药率也迅速增加。目前重庆地区治疗小儿菌痢宜推荐先锋霉累Ｖ、环丙沙星、头孢噻肟、卡那霉素，待有药敏试验结果后结合临床效果进行调整。     

抗性家蝇蛹期多肽的双向电泳分析

分析抗性家蝇蛹期多肽，以了解蛋白质变化情况。方法：对家蝇的抗性株、对照株和敏感株蛹体内的多肽进行了聚丙烯酸胺凝胶电泳分析。结果：抗性株具有一特异的多肽点，且有3个多肽点在量上明显多于对照株。结论：杀虫剂的作用可使抗性家蝇体内的蛋白在质和量上发生改变。     

Hepatitis C virus (HCV) genotype 1 NS5A resistance-associated variants are associated with advanced liver fibrosis independently of HCV-transmission clusters

Objectives

The aim of the study was to characterize the differences in the frequencies of NS3 and NS5A resistance-associated variants (RAVs) among Polish therapy-naive genotype 1 (G1) hepatitis C virus (HCV)-monoinfected and human immunodeficiency virus (HIV)/HCV-coinfected patients including clustering patterns and association of RAV frequency with liver fibrosis.

Electrical analogy of diastolic pressure difference between left atrium and ventricle

We proposed a mathematical model to describe the early filling process of the left ventricle and applied the model toin vivo experiments. The solution of a second-order differential equation indicated that the pressure difference between the left atrium and ventricle during ventricular filling (PD) could be explained by a transient response, i.e. decremental oscillation, in an LCR circuit. Thereafter, we analysed the sequence of PD during vagal stimulation with two catheter-tip manometers in 12 anaesthetised dogs and evaluated changes in the parameters of the system under various haemodynamic conditions. The values of ω_n and ξ were quite stable among beats within an episode of vagal stimulation, between episodes and even among dogs, despite the changes in haemodynamic variables. Pericardiotomy and partial discommunication of the mitral valve with the left ventricular free wall by cutting the mitral chordal tendons decreased ω_n and increased ζ, mainly because of the increase in C_LV. Occlusion of the coronary vascular beds with large numbers of microspheres increased ω_n and decreased ζ, mainly because of the decrease in C_LV. Mitral obstruction with an inflated balloon (increase in R) abolished the oscillatory changes and produced and exponential decay sequence of PD. In conclusion, both the logical and experimental approaches indicated that the sequence of PD could be considered as decremental oscillation in the LCR circuit and the parameters ω_n and ξ could be good indices of the diastolic property of the left ventricle