BIOCHEMICAL CORRECTION IN THE SYNDROME OF HYPERTENSION AND HYPERKALAEMIA BY SEVERE DIETARY SALT RESTRICTION SUGGESTS RENIN-ALDOSTERONE SUPPRESSION CRITICAL IN PATHOPHYSIOLOGY

1. Plasma potassium and chloride concentrations were raised and plasma renin activity, aldosterone, bicarbonate and arterial pH were reduced in two brothers with the syndrome of hypertension and hyperkalaemia with normal glomerular filtration rate (Gordon's syndrome), on unrestricted or moderately restricted sodium diets. 2. These abnormalities were corrected in both patients within 10 days of severe sodium restriction. 3. Pressor sensitivity to cold and angiotensin II decreased on low sodium diet, associated with a fall in blood pressure. 4. Increasing distal tubular sodium delivery by infusion of normal saline increased fractional excretion of potassium when aldosterone had been stimulated by severely restricted sodium diet, but not when aldosterone levels were low on unrestricted sodium diet. 5. These findings are consistent with excessive sodium reabsorption as the primary renal lesion in Gordon's syndrome, leading to volume expansion and suppression of renin and aldosterone. Severe dietary sodium restriction leading to volume contraction, by stimulating renin and aldosterone and promoting kaliuresis, corrects the abnormalities.     

Peak Endocardial Acceleration-Based Clinical Testing of the "BEST" DDDR Pacemaker

The peak endocardial acceleration (PEA, unit g) shows a near correlation with myocardial contractility during the isometric systolic contraction of the heart (dP/dtmax), with sympathetic activity and, thus, with physiological heart rate modulation. The (Biomechanical Endocardial Sorin Transducer (BEST) sensor is incorporated in the tip of a pacing lead and measures PEA directly near the myocardium. In an international study, the lead was implanted with the dual chamber pacemaker Living-1 (Sorin) in 105 patients. The behavior of the PEA signal was tested under conditions of physical and mental stress and during daily life activities by 24-hour recordings of PEA (PEA Holter) at 1 to 2 months and approximately 1 year after implantation. Implantation of the BEST lead was performed without complications in all patients. The sensor functioned properly in the short- and long-term in 98% of patients. Although PEA values differed from patient to patient, the values closely reflected the variations in sympathetic activity due to physical and mental stress in each patient. During exercise and during daily life activities a close correlation between PEA and heart rate was observed among patients with normal sinus rhythm. Peak endocardial acceleration allows a nearly physiological control of the pacing rate.     

Influence of Preparation Factors on the Sustained Release of Nifedipine from Eudragit RL/RS Microspheres

用乳剂—溶剂挥发法制备硝苯地平的丙烯酸树脂缓释微球。微球中药物的释放速度随丙烯酸树脂ＥｕｄｒａｇｉｔＲＬ／ＲＳ比率的增加以及制备时搅拌速率的增加而增大，随内相聚合物浓度的增加及微球粒径的增加而减小，释药５０％所需时间与微球粒径呈良好线性。微球的释药速率也随药物含量的增加（从４．２％到１６．７％）而增大，并快于药物结晶的溶解速率，但药物含量达２６．６％时，微球释药速率明显下降并低于药物结晶的溶解速率。用差热分析和Ｘ射线衍射分析证明，药物含量为４．２，９．４和１６．７％的微球中药物完全是以非晶态分散的，而含药２６．６％的微球中有药物结晶存在。不同微球释药低于７０％时，释放方式均符合Ｈｉｇｕｃｈｉ时间平方根方程。     

1870株致病菌感染概况及敏感性情况

目的了解临床标本中主要致病菌分布及敏感性分析，指导抗生素的选择及合理治疗方法对我院1994～1996年临床分离的1870株细菌的分布及敏感性、耐药性进行分析，1996年与1994年的结果进行比较，并将1995年的结果与北京地区5家教学医院同年的结果进行比较。结果分离菌株主要分布于呼吸道、消化道、泌尿道、血液及骨髓。G＋菌占10.5％，G-菌占89.5％，占明显优势。沙门氏菌对头孢唑啉和哌拉西林的耐药性明显降低（P＜0.01），大肠埃希氏菌对氨苄西林和氟嗪酸的耐药性明显增高（P＜0.01），其余菌株无明显差异。抗生素敏感性覆盖率最高的是复达欣，其次为丁胺卡那，最低者氨苄西林。大肠埃希氏菌、假单胞菌对哌拉西林的耐药率，克雷伯杆菌属对西力欣的耐药率，肠肝菌属对哌拉西林的耐药率均高于北京地区。结论本组资料显示不断监测和分析菌丛的变化及对不同抗生素耐药性出现的频率和耐药谱至关重要。     

老年男性心肌缺血患者心率变异分析（附67例报告）

采用正常搏动ＲＲ间期的标准差（ＳＤ）及心率变异指数（ＨＲＶ ｉｎｄｅｘ）作为指标，分析６７例老年男性心肌缺血患者的心率变异，并与正常老年男性组及正常青壮年男性组进行了对比，发现前组的ＲＲ间期ＳＤ、ＨＲＶｉｎｄｅｘ均明显低于后两组，其结果有显著性差异（Ｐ均〈０．０１）。提示心肌缺血可破坏交感与迷走神经的均衡性，造成心率变异降低。     

胎儿声振动刺激反应的研究

目的：了解不同孕龄胎儿对声振动刺激的反应。方法：对４３５例次正常中、晚期妊娠妇女进行声振胎心试验（ＶＡＳ－Ｔ）、声振胎动试验（ＳＰＦＭ），并对声振动刺激前、后胎心率变化规律进行前瞻性研究。结果：（１）从２４周开始，胎儿对声振刺激有反应，但大部分未能达到ＶＡＳ－Ｔ诊断标准，而胎动反应良好。（２）妊娠２８周开始，声振刺激后，９０％以上的胎儿出现显著的胎动、胎心率加速反应，足月胎儿反应率在９８％以上。（３）ＳＰＦＭ阳性率的显著提高早于ＶＡＳ－Ｔ。提示：２８周后胎儿神经系统发育已趋完善。胎儿运动神经的发育成熟早于植物神经。     

左心室舒张(充盈)功能的影响因素

本文用X线电影摄影方法评价了49例左室舒张(充盈)功能的影响因素。冠心病(CAD)组23例,高血压病组12例,正常对照组14例。左室充盈功能或顺应性主要受冠脉病变严重程度的影响。冠脉狭窄程度越重,并有陈旧性心肌梗塞、室壁运动异常、EF下降,则充盈功能受损愈明显。血压、年龄因素对舒张充盈功能的影响较小。在CAD组中,心率与1/3充盈分数呈负相关,与正常化高峰充盈率(NPFR)不相关,而EF则与NPFR相关良好。     

烟台市区风疹爆发的流行病学调查

本文报告了1987年2~5月间烟台市区幼儿园、小学等集体机构发生的一起出疹性疾病。经调查和血清学检测证实为风疹。总罹患率为23.99%,有的班级高达83.33%。具有流行迅速、发病集中、临床表现较重等特征。其中一例于发疹后期并发脑炎死亡。     

三七粉末透皮吸收研究

目的 :研究三七粉末的透皮吸收性及选择最佳促透剂。方法 :设计体外离体透皮试验法 (即用离体鼠皮在单室扩散池中进行试验 ) ,测定不同时间三七粉末中有关成分的透皮总量 (以三七皂苷为对照 ) ,计算透皮吸收率及促透剂的促透倍数。结果 :三七粉末的丙二醇溶液有一定透皮吸收能力 ,不同浓度的氮酮 (Azone)对其具有显著的促透作用 ,但Azone的促透效果与其剂量不呈直线关系 ,5 %Azone效果好于 7%Azone。结论 :本方法简便、易于操作、重现性较好 ,可用于制剂工艺研究中促透剂的选择     

Regulation of local sweating in sleep-deprived exercising humans

Summary Thermoregulatory sweating [total body (m _sw,b), chest (m _sw,c) and thigh (m _sw,t) sweating], body temperatures [oesophageal (T _oes) and mean skin temperature (T _sk)] and heart rate were investigated in five sleep-deprived subjects (kept awake for 27 h) while exercising on a cycle (45 min at approximately 50% maximal oxygen consumption) in moderate heat (T _air andT _wall at 35° C. Them _sw,c andm _sw,t were measured under local thermal clamp (T _sk,1), set at 35.5° C. After sleep deprivation, neither the levels of body temperatures (T _oes,T _sk) nor the levels ofm _{sw, b},m _{sw, c} orm _{sw, t} differed from control at rest or during exercise steady state. During the transient phase of exercise (whenT _sk andT _sk,1 were unvarying), them _{sw, c} andm _{sw, t} changes were positively correlated with those ofT _oes. The slopes of them _{sw, c} versusT _oes, orm _{sw, t} versusT _oes relationships remained unchanged between control and sleep-loss experiments. Thus the slopes of the local sweating versusT _oes, relationships (m _{sw, c} andm _{sw, t} sweating data pooled which reached 1.05 (SEM 0.14) mg·cm^–2·min^–1°C^–1 and 1.14 (SEM 0.18) mg·cm^–2·min^–1·°C^–1 before and after sleep deprivation) respectively did not differ. However, in our experiment, sleep deprivation significantly increased theT _oes threshold for the onset of bothm _{sw, c} andm _{sw, t} (+0.3° C,P<0.001). From our investigations it would seem that the delayed core temperature for sweating onset in sleep-deprived humans, while exercising moderately in the heat, is likely to have been due to alterations occurring at the central level.