Role of endothelin in the pathogenesis of hypertension in spontaneously hypertensive and 2 kidneys 1 clip rats.

The plasma endothelin (ET) level in spontaneously hypertensive rats (SHR) and 2K1C hypertension animal models and its vasoconstrictive effect on renal and tail arteries were studied. The results demonstrated that there was no difference in plasma ET level between the hypertensive groups SHR, 2K1C, normotensive control groups Wistar Kyot (WKY) and Sprague Dawley (SD), while the vasoconstrictive effect of ET in SHR was more dominant than in WKY. The EC50 of the renal and tail arteries in SHR (0.8912 +/- 0.1662 x 10(-8) M, 0.6103 +/- 0.0878 x 10(-8) M) was apparently lower than that in WKY (1.77 +/- 0.2991 x 10(-8) M, 1.2267 +/- 0.2502 x 10(-8) M, P less than 0.05), but no difference was found in 2K1C and SD rats. The four groups of animals exhibited no difference of such effects as response to norepine-phrine (NA). The findings suggested that the increased arteriole sensitivity to ET be an important factor in the pathogenesis of hypertension in SHR.

     

572例近视眼患者中央角膜厚度测量报告

本文作者在572例(1144只眼)近视眼患者拟行角膜放射状切开(RK)手术前,对角膜不同部位厚度进行了测量,对其值作统计学处理,均值及标准差为0.527±0.037mm,标准误为0.002,说明我国95％的近视眼患者中央角膜厚度范围为0.455—0.600mm。提示我国成人各年龄组左、右眼角膜厚度与左、右眼屈光度、性别、眼别无关。强调RK手术前对角膜厚度测量的重要性,但手术预后优劣为多因素所致。     

The platelet interactivity phenotype of Streptococcus sanguis influences the course of experimental endocarditis.

A strain of Streptococcus sanguis that induced rabbit platelets to aggregate in vitro (Agg+ phenotype) was hypothesized to be a more virulent pathogen than an Agg- strain in experimental endocarditis in rabbits. A left ventricular catheter was implanted, and then an Agg+ or Agg- strain was inoculated intravenously. Vegetations formed on the aortic semilunar valves but were unaffected by the duration of implantation of the catheter. Vegetations enlarged by accumulating platelets and their mass increased directly with the duration of endocarditis. Inoculation of the Agg+ strain consistently caused endocarditis with significantly larger vegetations, a more severe clinical course (including febrile episodes, hematological changes, and signs of myocardial ischemia), more gross lesions in major organs, and greater mortality than inoculation with the Agg- strain, saline, or the Agg+ strain pretreated with monospecific rabbit immunoglobulin G or Fab fragments against its platelet aggregation-associated protein (PAAP; class II). In experimental endocarditis, PAAP expressed by Agg+ S. sanguis appeared to be an important virulence factor.     

经内镜胆管引流术在肝门部恶性胆管梗阻中的应用及其评价

肝门部恶性肿瘤手术切除率极低，临床处理十分棘手。作者采用内镜胆管引流术治疗此类肿瘤２８８例次（肝门部胆管癌１８４例、胆囊癌２３例、肝细胞癌侵犯肝门部胆管４７例、其他转移性肿瘤３４例），其中行内镜鼻胆管引流１６２例次、塑料内置管引流８０例次、放置可膨式金属胆道支架４６例、４例患者接受同期双内置管引流。引流总有效率为６７．０％，其中效果满意者４３．１％；４０例患者术后１个月内发生胆管炎，发生率为１３．８％，３例死亡；长期随访病例的平均存活期５．３个月。我们观察到治疗的效果与Ｂｉｓｍｕｔｈ分型有密切关系，如果全肝４０％以上的胆系得到引流，黄疸有望消退；左、右两侧胆管同时引流可扩大引流范围，提高疗效；应合理选择三种内镜胆管引流方法并适时灵活转换才能获得满意的疗效。结论：对于肝门部肿瘤，内镜胆管引流术是一种安全有效的治疗手段，可作为首选的姑息性治疗。     

镍作业工人细胞免疫功能、血清硒和过氧化脂质含量的变化

９６名镍作业工人测定结果：非特异酯酶阳性细胞百分率（ＡＮＡＥ＋％）为７６．８％±８．０％，Ｔ细胞亚群ＣＤ２、ＣＤ４、ＣＤ８阳性细胞百分率（ＣＤ＋２％、ＣＤ＋４％、ＣＤ＋８％）及ＣＤ＋４／ＣＤ＋８比值分别为６５．６％±１０．５％、５６．３％±１２．１％、３４．３％±８．２％和１．７６±０．６；酵母多糖刺激的外周血多形核白细胞化学发光（ＰＭＮ－ＣＬ）本底和峰值分别为４８±２３和３０７３±６８４ＣＰＳ／１０６ＰＭＮ；血清硒和丙二醛含量分别为１．２２±０．２３和４．７６±０．８８μｍｏｌ／Ｌ。与非镍作业的地区对照组比较，Ｔ细胞ＣＤ＋８％增高，ＣＤ＋４／ＣＤ＋８比值下降，化学发光的本底值降低，峰值增加，血清Ｓｅ含量下降，丙二醛含量升高。分析镍作业工人工龄与后三项指标变化的关系，工龄大于２０年与小于１０年有统计学上明显差别。这些观察指标为镍作业人员医学观察增加新的监护指标提供依据。     

原发性青光眼的激光治疗

目前在青光眼的临床治疗中，激光治疗已成为介于药物和手术治疗之间的一种方法，本文仅就原发性闭角型青光眼的激光周边虹膜透切术和开角型青光眼的激光滤帘成形术做一介绍。     

Complement Killing of Yersinia enterocolitica and Retention of the Bacteria by Leucocyte Removal Filters

We report studies on the complement sensitivity of four strains of Yersinia enterocolitica , serotypes O:3, O:9, O:5,27, and O:20, isolated from blood units involved in transfusion fatalities. Complement in fresh CPD plasma killed Y. enterocolitica within 4 h at 22°C in 100% of the experiments. The bactericidal action was serotype and complement activation pathway dependent. Both classic and alternate pathways seemed to be active, but the latter to a lesser degree. When the classic pathway was blocked by chelation of Ca²⁺ no complete killing was obtained. Complement did not enhance or condition Yersinia for leucocyte filter retention. Direct removal of Yersinia by filtration was also related to serotype; all strains were reduced by filtration in heat-inactivated plasma, and all except serotype O:5,27 were reduced in Ca²⁺ -chelated plasma. Our findings may explain why plasma products and platelet concentrates are rarely involved in Yersinia sepsis related to transfusion.     

Man-Machine Interfaces in Computer Assisted Surgery

The clinical potential of computer assisted surgery (W) has been more and more widely acknowledged since CAS systems have been introduced into the operating room (OR) theater.

Especially the improvements in safety and accuracy are remarkable and strengthen the ties between surgeons and engineers. Tumor stereotaxis was introduced to neurological surgery in the early 1980s, and currently systems with and without robotic navigation are in use for specific medical indications. Recently, solutions for computer assisted orthopedic surgery were developed and applied to various anatomical regions. However, with the establishment of CAS in vivo, a new complex of problems, which was not present in the laboratory setup, was introduced: the man-machine interface.

Currently, the complexity of available CAS systems requires the presence of at least one system engineer (often called the “operator”) in the OR. As a consequence, there is no possibility for direct communication between the surgeon and the machine or software.

Most of the program steps involved in CAS and choices to be made intraoperatively have to be transferred to the software by means of communication of the surgeon with the operator. Particularly, the establishment of a relation between the virtual object (i.e., a medical image) and the surgical object (i.e., the patient), often denoted as “matching” or “skeletal registration” requires intensive interaction of the surgeon with the computer. A literature survey revealed that no CAS system in clinical use exists without a system engineer or a comparable person, and our clinical experience indicated that the matching process is a weak point in most systems. Because it appears to be contradictory to cost-reduction efforts in health care to have a highly paid specialist in the OR, this research evaluates strategies to facilitate the man-machine interface with the final goal of establishing a direct control of the system by the surgeon or the medical personnel traditionally present at surgery. Options to be investigated include 1) a CAS control panel (virtual keyboard) as an integrated component of the existing navigation system and 2) introduction of a commercial voice-recognition system. The implementation of these strategies into the existing CAS setup at the Department of Orthopaedic Surgery at the Inselspital (University of Bern) and clinical experience gained are reported     

维甲酸改变人肝癌细胞表面N－糖链的结构及其酶学机制

用３Ｈ－甘露糖标记７７２１人肝癌细胞表面糖蛋白的Ｎ－糖链，经提取和去唾液酸后，用ＣｏｎＡ和ＤＳＡ亲和柱顺序层析将３Ｈ－标记的Ｎ－糖链分成４个类型和天线数不同的组分来研究维甲酸（ＲＡ）对细胞表面Ｎ－糖链的影响。结果：１０μｍｏｌ／ＬＲＡ处理细胞３～５ｄ后，可使Ｃ２Ｃ２二天线复杂型Ｎ－糖链增加，而高甘露糖型及三、四天线，特别是带有Ｃ２，６分支结构的复杂型Ｈ－糖链减少。用ＬＣＡ亲和柱还证明二天线糖链中的核心岩藻糖也减少。进一步发现上述改变的酶学机制是ＲＡ降低Ｎ－乙酰氨基萄葡糖转移酶Ｖ和α－１，６－核心岩藻糖转移酶的活力。结论：ＢＡ通过改变某些糖基转移酶活力而改变细胞表面糖链结构，这可能是ＲＡ使７７２１细胞诱导分化的机理之－。