The Krotkoff sound

As the auscultatory method of blood pressure measurement relies fundamentally on the generation of the Korotkoff sound, identification of the responsible mechanisms has been of interest ever since the introduction of the method, around the turn of the century. In this article, a theory is proposed that identifies the cause of sound generation with the nonlinear properties of the pressure-flow relationship in, and of the volume compliance of the collapsible segment of brachial artery under the cuff. The rising portion of a normal incoming brachial pressure pulse is distorted due to these characteristics, and energy contained in the normal pulse is shifted to the audible range. The pressure transient produced is transmitted to the skin surface and stethoscope through deflection of the arterial wall. A mathematical model is formulated to represent the structures involved and to computer the Korotkoff sound. The model is able to predict quantitatively a range of features of the Korotkoff sound reported in the literature. Several earlier theories are summarized and evaluated.     

积分加权法评价磷化学烧伤实验病理的意义与应用

目的：积分加权法在病理组织学检查中的应用，方法：在常规病理描述基础上，采用积分加权法将病理结果予以定量，综合评价致伤后实验动物的主要脏器，结果：实验动物同等面积的磷酸烧伤各脏器积分降低，钙治疗后则显著改善，均与其它方面报道的资料一致，结论：积分加以数值使各脏器损伤程度一目了然，对不同脏器间的损伤情况有可比性，从而有助于了解主要受损脏器与总体的关系以及药物的治疗效果。     

Human Peripheral Eosinophils with Receptors for IgM: Demonstration and Ultrastructural Morphology

Receptors for IgM were detected on peripheral blood human eosinophils by a rosette technique with ox red blood cells coated with the IgM fraction of the specific immunserum. Between 14 % and 43 % (mean 27 %) FcµR positive cells were found after an overnight incubation period at 37°C by using this technique. The specificity of the receptors for IgM was assessed by studying the inhibitory capacity of purified human IgM in the rosette assay. From an ultrastructural point of view, the EA^M rosette-forming cells are mature eosinophlic granulocytes characterized by a nucleus with a variable number of lobes and a certain number of «first type» granules partially or totally devoid of their content.     

改良式剖宫产术50例临床分析

探讨改良式剖宫产术的临床价值。方法：采用香港周杰医师１９９１年创立的一套改式剖宫产术对５０例产妇进行手术并与同期腹部横切口传统剖宫产术进行比较。结果：改良式剖宫产术所用时间短,术中出血小,术后排气暗暗科痛轻、产褥病发生率低。住院时间短,与对照组比较有明显差异。     

Pregnancy: Effects of hyperosmolar glucose, prostaglandin-F2{alpha} and 15-methyl-prostaglandin-F2{alpha} on human placental cells in vitro

The objective of this study was to assess the ability of certaindrugs, used for local injection therapy of ectopic pregnancy,to suppress the activities of cultured human placental cells.Placental cells from legal first trimester abortions were preparedby collagenase treatment and density gradient centrifugation.The cells were exposed to hyperosmolar glucose (500 mg/ml),15-methyl-prostaglandin-F₂ (15-m-PGF₂; 10–7 to 10–3mol/l) and prostaglandin-F₂ (PGF₂; 10–5 to 5X10–3mol/l) for 30 min on days 2–4 after seeding. The effectson the secretion of human chorionic gonadotrophin (HCG) andprogesterone, as well as on the protein content per culturewell, were measured. Hyperosmolar glucose was the most effectivedrug and caused a marked decrease of the protein content inthe culture wells and a reduction of progesterone secretion.Of the two prostaglandins, only 15-m-PGF₂ affected the viabilityof the cells and reduced the protein content of the wells. Theclinical effectiveness of the two groups of drugs seems to besimilar but certain in-vitro effects are different. Thus invivo they may act on different target tissues. Against thisbackground, the combination of hyperosmolar glucose and prostaglandinsmight be an interesting approach for local injection therapyfor tubal pregnancy.     

Establishing priorities for European collaboration in communicable disease surveillance

Background: Several collaborations in communicable disease surveillancehave developed between European Union member states. Involvementin these activities takes time and money. It is vital that collaborationsare established in areas most likely to be beneficial. An exercisewas undertaken to inform national surveillance centres and theEuropean Commission as to priority areas for the developmentof collaborations. Methods: A modified Delphi exercise was undertakenamongst the heads of centres with responsibilities for surveillanceat national level in the member states of the EU. Participantsdeveloped, agreed and ranked criteria for developing collaborations.A list of communicable diseases and syndromes was then rankedusing a Likert-type scale. Three rounds were undertaken. Betweenrounds, scores and a ranking were fed back showing where participantshad ranked items, compared to the overall mean and rank distribution.For the third round participants were asked to use a categoricalscale, nominating six or ten high priority disease areas. Results:Response rates were 87.5% for round 1, 44% round 2 and 87% round3. The low round 2 response rate appeared to be because respondentsdid not wish to alter their rankings. The six high priorityareas were outbreaks of gastroenteritis/food poisoning, CID/otherslow virus infections, serious imported diseases, legionellosis,antimicrobial resistance and tuberculosis. When participantsgave ten high priority areas meningococcal disease, travel advice,vaccination/immunization and influenza were also included. Thefinal lists were accepted at the meeting of participants. Conclusions:The process was successful in developing both a priority listand consensus.     

KD306型耐硫甲烷化催化剂有效扩散系数的测定

基于开发的计算机取样系统,采用ＳＰＳＲ法脉冲动态测试ＫＤ３０６型耐硫甲烷化催化剂的有效扩散系数。线性化和参数估值的结果吻合较好,证实：线性化简化是合理的,参数估值是可用于有效扩散系数。ＫＤ３０６型耐硫甲烷化催化剂的曲折因子为７．２。     

高晶体-高胶体渗透压溶液对受机械性损伤的海马神经细胞容积的影响

观察机械性损伤的海马神经细胞在不同浓度高晶体－ 高胶体渗透压溶液中容积的变化。取原代培养大白鼠胚胎的海马神经细胞,用超声波机械损伤细胞后暴露于含０．５ ｇ／Ｌ、１ ｇ／Ｌ和２．５ ｇ／Ｌ氯化钠的细胞培养基中１５ ｍ ｉｎ。结果显示机械性损伤的细胞明显肿胀（Ｐ＜ ０．０５）。当细胞暴露于不同浓度的高晶体－ 高胶体溶液１５ ｍ ｉｎ 后, 细胞容积与同一实验时间的对照值相比明显下降, 并保持至第７ ｄ （Ｐ＜ ０．０５）。表明受到机械性损伤的海马神经细胞在高晶体－ 高胶体渗透压环境中的容积调节功能丧失或减弱。     

单宁酸——氯化铁法媒染肝微血管的光镜研究

目的：光镜下观察单宁酸－－氯化铁法媒染的肝内微血管构筑。方法：用单宁酸配制的混合媒染固定液灌流大鼠,取肝脏冰冻切片,入氯化铁溶液中呈色。结果：肝小叶中央静脉、肝血窦以及小叶间动、静脉、小叶下静脉均显示良好,肝小叶周边有很横断面的血窦,肝板较饱满,窦壁上有许多细丝缠绕。结论：单宁酸－－氯化铁法可很好地显示肝内微血管构筑,小叶周边存在与中央静脉平行的血窦。     

导管法测定大鼠肺循环血流量的研究

目的：研究一种新的导管法测定肺循环血流量。方法：分离右侧颈外静脉,将塑料导管自右侧颈外静脉插入,经上腔静脉、右心房和右心室插入肺动脉。用上海产ＳＪ—４２型四导生理记录仪记录生理参数。结果：肺循环血流量可按公式ＱＰ＝ＭＰＡＰ·△ＱＭＰＡＰ－ＭＰＡＰ计算,式中△Ｑ是每分钟自肺循环流入容量测定计的血量,算得的ＱＰ＝２９．６２±３．７３ｍｌ／ｍｉｎ,在大鼠的肺循环血流量正常范围之内。结论：该方法精确而且操作简便