Practice improves even the simplest movements

Summary Three subjects practiced accurate, fast elbow flexions of 54° to a 3° wide target. Movements of 36°, 54° and 72° were then tested. Comparison over the three distances showed that the normally monotonic relationship between movement distance and movement time is alterable by specific training. Subjects learn to go faster over the practiced distance by refining their neural commands to the muscles. The benefits of practice only partially transfer to other distances. We conclude that many of the relationships seen among movement variables in simple tasks are plastic in nature and affected by prior experience.     

Studies on subcutaneous fat necrosis of the newborn

Summary Biopsy specimens from the skin and subcutaneous fat tissue of four cases with neonatal subcutaneous fat necrosis were made and investigated by light and electron microscopy at 2, 4, and 6 weeks, and 5 months (Case 2) from the onset of the disease. Three stages of ultrastructural change of fat cells were observed. The evolution of crystal formation in the fat cells was seen and phagocytosis of crystals and fat droplets by macrophages and foreign-body giant cells was also noted. In the light microscope accumulation of calcium concretions in the spaces between and inside the fat cells was found. In the electron microscope we detected foci of highly electrondense granules, which were similar in distribution and structure to calcium salts stained with the von Kossa method. Changes in small and medium size blood vessels were observed.This work was written during a stay supported by Max-Planck-Gesellschaft from Dec. 1. 1973 to March 31. 1975 in the Max-Planck-Institut für Klinische und Physiologische Forschung (W.G. Kerckhoff-Institut), Bad Nauheim, West Germany (Director: Prof. Dr. Wolfgang Schaper)     

Sympathoinhibition by rilmenidine in conscious rabbits: involvement of α2-adrenoceptors

Summary Cardiovascular and sympathetic nervous system effects of the mixed ₂-adrenoceptor and imidazoline receptor agonist rilmenidine were studied in conscious rabbits chronically instrumented for the recording of the firing rate of renal sympathetic fibers. Separate experiments were carried out on pithed rabbits with electrically stimulated (2 Hz) sympathetic outflow. Drugs were administered intravenously in a cumulative manner.In conscious rabbits, rilmenidine 0.1, 0.3 and 1.0 mg kg^–1 dose-dependently lowered blood pressure, renal sympathetic nerve activity, heart rate and the plasma concentration of noradrenaline and adrenaline. The effect on blood pressure and plasma catecholamines was maximal after 0.3 mg kg^–1 whereas heart rate and renal sympathetic nerve activity decreased further after rilmenidine 1.0 mg kg^–1. Yohimbine 0.1 and 0.5 mg kg^–1, when injected subsequently, attenuated and at the higher dose abolished all effects of rilmenidine. The effects of rilmenidine were also antagonized by the ₂-adrenoceptor antagonist 2-(2,3-dihydro-2-methoxy-1,4-benzodioxin-2-yl)-4,5-dihydro-1H-imidazole HCl (RX821002; 0.1 and 0.5 mg kg^–1). Yohimbine 0.1 and 0.5 mg kg^–1 did not attenuate or attenuated only slightly the decrease of heart rate and renal sympathetic nerve activity produced by infusion of vasopressin. In pithed rabbits with electrically-stimulated sympathetic outflow, yohimbine 0.1 submaximally and yohimbine 0.5 mg kg^–1 maximally increased the plasma noradrenaline concentration.The experiments show by direct measurement of sympathetic nerve firing and plasma catecholamines that rilmenidine causes sympathoinhibition in conscious rabbits, presumably through central sites of action. The antagonism by yohimbine, at doses which are selective for ₂-adrenoceptors (vs. imidazoline receptors), demonstrates the involvement of ₂-adrenoceptors in the sympatho-inhibition.Correspondence to: B. Szabo at the above address     

Does calcium balanced heparin affect blood gas and electrolyte analysis?

The effect of calcium-balanced heparin (471896, CIBA CORNING) on blood gas and electrolyte analysis was evaluated, by comparing with that of sodium heparin (Na heparin). One ml of whole blood was collected into a syringe, which contained calcium-balance heparin (Ca balanced heparin) or Na heparin. 122 pairs of blood samples obtained from 15 patients were analyzed for Na, K, ionized calcium (Ca(++)), total hemoglobin, pH, P(CO)(2), and P(O)(2) by an automatic blood gas and electrolyte analyzer, CIBA CORNING model 288. There was a significant difference ( P < 0.05) in pH, P(CO)(2), Na, and Ca(++) between the two different groups. Ca(++) concentration was significantly less in Na heparin group than in Ca balanced heparin group, probably due to more chelation of Ca(++) by Na heparin than Ca balanced heparin. The present study suggests that the Ca balanced heparin has minimal effect on the blood gas and electrolyte analysis, and is a suitable anticoagulant for the Ca(++) measurement.     

凝血酶烧伤膏治疗血液病鼻衄的临床观察

目的 为探讨血液病鼻衄的理想处理方法。方法 对２３例治疗组患者采用浸有凝血酶２０００Ｉｕ／ｍｌ的明胶海绵局部敷贴出血点,３～４日后用烧伤膏创面换药;３４例对照组采用凡士林纱条填塞止血。结果 治疗组有效率８６．９％,显效率６９．７％;对照组分别是５８．５％和３５．３％。两种方法有显著性差异（Ｐ〈０．０１）。结论 用凝血酶敷贴出血点及创面烧伤膏换药是治疗血液病鼻衄一种安全、有效的方法。     

血液血细胞比容血沉纤维蛋白原同血流变学相关指标检测的分析

本文通过临床常用的HCT、FIb、ESR与血流变中全血粘度、血浆粘度和红细胞聚集性之间相关性的实验对照观察、理论分析 ,认为血细胞比容 ,血沉和纤维蛋白原检测反映血液浓度、粘度、聚集、凝血状态是有一定相关价值。因此 ,再配合临床必要的生化实验 ,如血糖、血脂等检测采用微机对检测数据处理对心脑血管疾病的预测、疗效观察具有更实用的价值     

妇科术后硬膜外腔注射吗啡镇痛效果观察

对妇科术后硬膜外腔注射吗啡镇痛效果进行观察分析探讨。对３ａ来我院使用术后硬膜外腔注射吗啡镇痛效果进行评定,对血压、脉博等情况观察进行总结分析。结果：硬膜外腔注射吗啡术后镇痛效果优８５．６％,良６．８％。副作用有血压下降达２７．８％、恶心呕吐１５．５％,头晕２３．０％。     

Detection of asymptomatic Leishmania donovani in healthy voluntary blood donors

ObjectiveTo check incidence of Asymptomatic Leishmania donovani reporting to Armed Forces Institute of Transfusion Rawalpindi.Material and MethodsTwo thousand (n = 2000) consecutive healthy voluntary blood donors were tested for 18 s rRNA by Real time Polymerase chain reaction. One thousand (n = 1000) subject’s permanent resident of Azad Kashmir along with a thousand (n = 1000) healthy voluntary blood donors from rest of Pakistan were included. The study was carried out over a period of three months Jun – Aug 2020.ResultsTotal of 2000 blood donors were enrolled in the study, all were males with age ranging from 16 to 60 years. Stratification based on residence, 1000 (50 %) resided in the Azad kashmir, 349 (17.45 %) were from Islamabad and Rawalpindi, 541 (27.05 %) from Punjab mainly residing in Lahore and Multan, 110 (5.5 %) were from other cities of Pakistan. Grouping on the basis of age, 55.25 % ( n = 1105) of the donors were 16–25 years old, 19.45 % ( n = 389) were in age range of 26–40 years old, 15.55 % ( n = 311) were 41–50 years old and 9.75 % ( n = 195) 51–60 years old. No donor was diagnosed as an asymptomatic carrier.ConclusionScreening of blood donors for Leishmania donovani is not recommended.     

Intrapulmonary gas mixing and dead space in artificially ventilated dogs

In this study we have investigated the effects of breath holding and of the physical properties of gases on four different respiratory dead spaces (V _D): the Fowler, the physiological, the washout and the inert gas dead space. The experiments were performed with dogs which were ventilated artifically with breathing patterns with different post-inspiratory breath holding times (t _a) of 0, 0.5, 1.0 and 2.0 s. Tracer amounts of acetone, ether and enflurane were infused continuously into a peripheral vein and a bolus of a mixture of krypton, Freon12 and SF₆ was introduced into the peritoneal cavity. After reaching steady state, samples of arterial blood, mixed venous blood and mixed expired air were taken simultaneously. From the partial pressures (P _a, P _¯V and P respectively) we determined the excretion (=P/P_¯V), retention (R=P_a/P_¯V) and the physiological dead space fraction (V _D,phys/V _T=(1 P/P_a) for each gas, where V _T is tidal volume. Further, we recorded the expirograms of the six tracer gases and of CO₂ from which the Fowler dead space fractions (V _D,Fowler/V _T) of the different gases were determined. Also the washout dead space fractions (V _D,washout/V _T) for He and SF₆ were determined as well as the inert gas dead space fraction (V _D,MIGET/V _T) with the use of the multiple inert gas elimination technique (MIGET).With the exception of V _D,phys/V _T for SF₆, all dead space fractions decreased with increasing t _a. V _D,phys/V _T for the poorly soluble gas SF₆ was considerably larger than V _D,phys/V _T for the remaining gases. For the highly soluble acetone V _Fowler/V _T was considerably smaller than V _D,Fowler/V _T for the other gases. V _{D,washout,SF6}/V _T was always larger than V _D,washout,He/V _T and V _D,Fowler,SF6/V _T. Further, V _D,phys/V _T was larger than V _D,Fowler/V _T for SF₆ and acetone. However, for gases with intermediate solubility in blood V _D,phys/V _T tended to be smaller than V _D,Fowler/V _T. We conclude that the respiratory dead spaces are affected by the breathing pattern and by the physical properties of gases, i.e. their diffusivity in alveolar gas and their solubility in blood or lung tissue.