高血压病与健康人毛细血管压及血液流变性检测的对比分析

高血压病与健康人毛细血管压及血液流变性检测的对比分析王宝忠，杨淑琴，邱玉霜，王福美，齐飞为了探讨高血压病人循环阻力与相关因素的关系，我们于１９９４年对高血压病人进行了甲襞毛细血管压、甲襞微循环、血液流变学等项同步检查并与健康人对比分析。１资料与方法资...     

无创正压通气患者发生鼻面部压疮危险因素的回顾性分析

目的:探讨分析无创正压通气(non-invasive positive pressure ventilation,NPPV)患者的鼻面部压疮发生情况及相关危险因素,为制定针对性的预防护理措施提供有效依据.方法:采用1∶1的病例-对照研究方法,通过查阅电子病历和护理记录收集患者在一般人口学特征、营养和疾病一般状况、无创正压通气使用情况以及鼻面部压疮发生情况等资料,采用Logistic回归性分析探讨影响持续无创正压通气患者鼻面部压疮发生的危险因素.结果:173名NPPV患者中发生鼻面部压疮的患者为48例(27.7％),其中Ⅰ期压疮为17例(9.8％),Ⅱ期压疮为30例(17.3％),Ⅲ期压疮为1例(0.6％);Logistic回归分析结果显示,年龄、Glasgow评分、SAS评分、血清白蛋白量、PaO2水平、面部水肿情况、NPPV使用方式、使用NPPV总时间、使用减压保护贴、糖尿病低血压、使用类固醇类药物和使用心血管活性药物是持续无创正压通气患者发生鼻面部压疮的影响因素.结论:鼻面部压疮是持续无创正压通气患者的常见并发症,临床护士可根据患者的具体情况及相关影响因素进行预防性护理,避免鼻面部压疮的发生.     

外部作用力引起组织压动态变化时的毛细血管血流

建立了组织压随中医推拿摆动类手法作用力发生动态变化时的毛细血管 -组织血液动力学模型 ,以此来解释中医推拿摆动类手法的血液动力学机制。血液在毛细血管内作低雷诺数流动 ,血浆渗出毛细血管壁遵循Starling定律 ,组织压随实测的滚法推拿作用力线性变化。同时考虑了血液表观黏度、血浆蛋白浓度、红细胞压积。数值计算了组织压动态变化时的毛细血管流量、血液表观黏度、渗透率和渗透因子 ,并和静态组织压的相应变量进行比较。结果显示 ,组织压动态变化导致毛细血管血流量有所增大 ,而血液表观黏度将下降 ,定性说明了中医摆动类手法的“活血化瘀”血液动力学机制。     

高血压病人毛细血管压与血压及甲襞微循环的关系

用无创性弹簧压片法,加压阻断毛细血管血流测量高血压病人治疗前后的毛细血管压,并同步观测甲襞微循环和上肢节段性血压。结果发现:治疗前后毛细血管压值分别为8.77±2.47、7.46±1.91kPa,治疗前值明显高于对照组(P<0.01),治疗后较治疗前明显下降(P<0.05)。同时发现高血压病人的毛细血管压与甲襞微循环加权积分值呈正相关(r=0.51,P<0.05);与肱、桡动脉压呈正相关(r=0.597、r=0.563,P<0.05);与指动脉压相关性差(r=0.297、P>0.05)。     

膀胱压与腹内压相关性的临床研究

目的研究膀胱压与腹内压相关性.方法选取腹腔镜胆囊切除术患者30名.排空膀胱后经Foley导管注入50ml生理盐水.置入18G气腹穿刺针后,连接自动电子充气连续测压仪,选取腹内压为0、5、10、15、20、25 mmHg时记录相应的膀胱压.结果当膀胱注入50ml的生理盐水后,腹内压由0增至25mmHg时,膀胱压与腹内压存在直线相关, 相关系数r=0.939(p<0.01),决定系数r2=0.882.结论膀胱压能准确估计腹内压.     

大白鼠齿龈微血管压和局部微区血流量测定

用无损伤性毛细血管测压仪和LDFⅡ型激光多普勒血流仪分别测定16只大鼠齿龈微血管压和局部微区血流量。结果:大鼠齿龈细动脉压为30.75±3.75mmHg,细静脉压为19.38±1.19mmHg微区血流量为18.89±4.16mv。提示:用无损伤性毛细血管测压仪测定齿龈微血管压,对机体无损伤,方法简单,重复性好。     

膀胱压与腹内压相关性的临床研究

目的　研究膀胱压与腹内压相关性 .方法　选取腹腔镜胆囊切除术患者 30名 .排空膀胱后经Foley导管注入 5 0ml生理盐水 .置入 18G气腹穿刺针后 ,连接自动电子充气连续测压仪 ,选取腹内压为 0、5、10、15、2 0、2 5mmHg时记录相应的膀胱压 .结果　当膀胱注入 5 0ml的生理盐水后 ,腹内压由 0增至 2 5mmHg时 ,膀胱压与腹内压存在直线相关 ,相关系数r=0 .939(p<0 .0 1) ,决定系数r2 =0 .882 .结论　膀胱压能准确估计腹内压     

组织压动态变化对毛细血管-组织交换的影响

本工作建立了组织压动态变化对毛细血管－组织交换影响的模型,数值计算了由于组织压动态变化时的渗透率FR^*,渗透因子FF和毛细血管内血液表观粘度μ,并和静态组织压情况进行了比较。结果表明由于组织压动态变化,使得这些重要的血液动力学参数均随之发生动态变化。在一般静态情况下,血液表观粘度将沿毛细血管增加,并保持在一个较高值。而在动态情况下,只要组织压动态变化幅度适当,那么在一定的时相内,血液表观粘度保持在一个较低值不再升高。这是中医推拿滚法和振法活血化瘀血液动力学机制的一个合理解释。     

新生儿脐静脉置管并发急性心包压塞4例报告

目的 分析脐静脉置管（UVC）相关急性心包压塞的临床特点，探讨其可能原因及预防。方法 回顾性总结近5年首都医科大学附属北京妇产医院4例脐静脉置管后心包压塞病例的临床特点、治疗和转归情况；结合文献复习，总结新生儿心包压塞的可能起因、临床特点、识别方法、治疗技术及防范措施，提出心包压塞的防治要点。结果 共纳入4例患儿，女1例，男3例，胎龄27～37周，出生体质量915～1950 g，生后1～5 h行脐静脉置管术，术后行X线定位导管顶端位置在T4～T6椎体水平，根据定位情况调整UVC位置后使用。患儿于置管后12～104h出现心率、血氧下降、心音低钝、遥远等心包压塞症状，给予心肺复苏、心包穿刺术后病情好转，拔除脐静脉置管后心包积液消失。心包压塞是脐静脉置管后的罕见且严重的并发症；UVC患儿出现血氧下降、心率改变（增快及下降）及心音低钝、遥远等症状需警惕心包压塞发生，导管位置偏移是其主要原因，放置UVC及时定位及定期X线或超声确认顶端位置非常必要；即刻床旁超声心动检查有助于心包压塞的快速诊断，及时心包穿刺抽液是挽救生命的关键。结论 心包压塞常导致休克及猝死。一旦使用UVC新生儿突然发生病情变化，...     

100例冠心病指动脉压、毛细血管压测定

微血管压力情况对机体的微循环状态有着重要作用,直接影响体循环循功能。故对冠心病人进行微血管压力测定有着十分重要的意义。指动脉压,毛细血管压基本上反映了微血管压力。直接法测量精度高,但需要专门设备,操作复杂,不适于临床。本文采用间接法测量指动脉压、毛细血管压,并同步测量血压、正中静脉压对     

人工心脏输出流量和压力的神经网络估算法

人工心脏的输出流量和压力是血泵设计及运行的重要特性参数 ,其测量精度和方法直接关系到人工心脏在动物实验及临床中的实际应用效果。本文提出了一种新的测量方法 ,即用神经网络从叶轮式人工心脏电机驱动参数换算血泵的流量和压力。与传统的测量方法相比 ,本方法具有如下特点 :(1)无创性 ,不会对血液造成破坏 ,同时减少了感染机会。 (2 )结构简单 ,省去了流量计和压力计 ,便于人工心脏完全植入体内。     

Does changing from mercury to electronic blood pressure measurement influence recorded blood pressure? An observational study.

Mercury sphygmomanometers have been commonly used in primary care to measure blood pressure but are associated with bias. Electronic blood pressure machines are being introduced in many practices and have anecdotally been associated with higher recorded blood pressure. This study examined recorded blood pressure in four practices before and after electronic blood pressure machine introduction. No consistent change in mean blood pressure was apparent following their introduction, but there was a large and significant fall in terminal digit preference suggesting improved precision of recording.     

Comparing indirect methods of digit ratio (2D:4D) measurement

The ratio of the lengths of the second and fourth finger (2D:4D) has been proposed to index prenatal exposure to androgens. Different methods have been utilized to measure digit ratio, however, their measurement precision and economy have not been systematically compared yet. Using different indirect methods (plastic ruler, caliper, computer software), three independent raters measured finger lengths of 60 participants. Generally, measurement precision (intraclass correlation coefficient, technical error of measurement, and relative technical error of measurement) was acceptable for each method. However, precision estimates were highest for the computer software, indicating excellent measurement precision. Estimates for the caliper method were somewhat lower followed by ruler which had the lowest precision. On the contrary, the software‐based measurements took somewhat longer to complete than the other methods. Nonetheless, we would favor the use of these tools in digit ratio research because of their relative superior reliability which could be crucial when associations with other variables are expected to be low to moderate or sample size is limited. Software offers several promising opportunities that may contribute to an accurate identification of the proximal finger crease (e.g., zooming, adjusting contrast, etc.). Am. J. Hum. Biol., 2009. © 2008 Wiley‐Liss, Inc.     

Automated method for detecting and reading seven-segment digits from images of blood glucose metres and blood pressure monitors

Abstract

There is an increasing need for fast and accurate transfer of readings from blood glucose metres and blood pressure monitors to a smartphone mHealth application, without a dependency on Bluetooth technology. Most of the medical devices recommended for home monitoring use a seven-segment display to show the recorded measurement to the patient. We aimed to achieve accurate detection and reading of the seven-segment digits displayed on these medical devices using an image taken in a realistic scenario by a smartphone camera. A synthetic dataset of seven-segment digits was developed in order to train and test a digit classifier. A dataset containing realistic images of blood glucose metres and blood pressure monitors using a variety of smartphone cameras was also created. The digit classifier was evaluated on a dataset of seven-segment digits manually extracted from the medical device images. These datasets along with the code for its development have been made public. The developed algorithm first preprocessed the input image using retinex with two bilateral filters and adaptive histogram equalisation. Subsequently, the digit segments were automatically located within the image by two techniques operating in parallel: Maximally Stable Extremal Regions (MSER) and connected components of a binarised image. A filtering and clustering algorithm was then designed to combine digit segments to form seven-segment digits. The resulting digits were classified using a Histogram of Orientated Gradients (HOG) feature set and a neural network trained on the synthetic digits. The model achieved 93% accuracy on digits found on the medical devices. The digit location algorithm achieved a F1 score of 0.87 and 0.80 on images of blood glucose metres and blood pressure monitors respectively. Very few assumptions were made of the locations of the digits on the devices so that the proposed algorithm can be easily implemented on new devices.     

一种基于足压数据主成分分析的足弓形态智能检测方法

目的 根据临床中平足与高弓足量化评估的要求,提出一种基于足压数据主成分分析（principal component analysis, PCA）智能快速足弓形态检测方法,并验证其临床有效性。方法 纳入诊断为足弓异常与足弓健康的志愿者,设计研发一套便携式足弓智能检测系统。采用44×52阵列式薄膜压阻传感器,采集静态站立式足底压力分布数据,利用自行编写的PCA算法自动拟合足轴线,进行足弓诊断并生成诊断报告。将足压采集结果与现有设备进行比对,验证足压数据的准确性。对于平足、高弓足和正常3类足弓的判别算法,通过对比临床诊断验证评估准确性。结果 该系统与现有压力采集设备的测量结果具有较好的相关性,接触面积偏差低于3.2%,计算拟合的足轴线与临床定义角度偏差小于1°,且该系统能获得与临床中足弓形态诊断相符率92.6%的评估结果。结论 引入PCA对足轴线自动化拟合,实现了快速而准确提取足弓信息的目的。该方法可用于临床实践中平足与高弓足的辅助筛查,有助于开展足弓畸形程度的量化分析和病理机制的研究。     

化学发光免疫分析定量检测乙肝病毒标志物方法学研究

采用碱性磷酸酶标记,金刚烷衍生物发光,自动化学发光分析仪测量等,进行乙肝病毒五种标志物化学发光免疫分析(CLIA)方法学研究.结果表明这五种标志物CLIA方法的精密度、灵敏度、回收率和临床符合率等技术参数均达到方法学和临床诊断的要求.CLIA方法比ELISA和RIA更简便、快速而实用,为临床诊断和科研工作提供了一种有用的检测手段.     

不同材料修复根管口喇叭形残根的实验研究

根管口呈喇叭形的残根用传统桩核修复时 ,常由于剪力集中在颈部和根尖 ,使得根管口薄壁不能承受较大的压力 ,在临床上因修复成功率较低 ,只能将牙根拔除。本文旨在对保留此类喇叭形残根提出一种新的修复方法 ,比较了化学固化树脂和传统玻璃离子粘固剂两种材料修复后的抗折能力 ,并与未修复组作对照。结果表明 ,根管口喇叭形残根先用化学固化复合树脂恢复其原有根管的形状和厚度 ,然后再制作桩核 ,对防止牙根的折裂具有明显的效果。用传统玻璃离子粘固剂修复根管口呈喇叭形残根与不作修复的对照组之间没有显著性差异。实验结果为临床保留此类喇叭形残根提供了可行性依据     

Effects of motor training on the recovery of manual dexterity after primary motor cortex lesion in macaque monkeys

To investigate the effects of postlesion training on motor recovery, we compared the motor recovery of macaque monkeys that had received intensive motor training with those that received no training after a lesion of the primary motor cortex (M1). An ibotenic acid lesion in the M1 digit area resulted in impairment of hand function, with complete loss of digit movement. In the monkeys that had undergone intensive daily training (1 h/day, 5 days/wk) after the lesion, behavioral indexes used to evaluate manual dexterity recovered to the same level as in the prelesion period after 1 or 2 mo of postlesion training period. Relatively independent digit movements, including precision grip (prehension of a small object with finger-to-thumb opposition), were restored in the trained monkeys. Although the behavioral indexes of manual dexterity recovered to some extent in the monkeys without the postlesion training, they remained lower than those in the prelesion period until several months after M1 lesion. The untrained monkeys frequently used alternate grip strategies to grasp a small object with the affected hand, holding food pellets between the tip of the index finger and the dorsum of the thumb. These results suggest that the recovery after M1 lesion includes both use-dependent and use-independent processes and that the recovery of precision grip can be promoted by intensive use of the affected hand in postlesion training.     

Initiation and development of fingertip forces during whole-hand grasping

The present study examined the initiation of digit contact and fingertip force development during whole-hand grasping. Sixteen healthy subjects grasped an object instrumented with force transducers at each digit and lifted it 10 cm. The grip (normal) and load (tangential) forces and the position of the object were recorded. Twenty-five lifts were performed with various object weights (300 g, 600 g, 900 g) and surface textures (sandpaper and rayon). Despite the large number of degrees of freedom, grip initiation with an object using the whole hand was characterized by stereotypical contact patterns, which are idiosyncratic to each subject across all object weights and textures. However, in spite of the initial asymmetric control, the forces were mainly synchronized by the occurrence of the peak grip and load force rates. The contribution of each digit to the total grip force decreased from radial to ulnar digits. The final force distribution was generally established already at the onset of load forces. Only subtle adjustments were seen thereafter, suggesting a fairly fixed force distribution pattern throughout the grasp. The findings suggest that, despite the large number of degrees of freedom in terms of contact initiation and force distribution in whole-hand grasping: (1) subjects employ preferred movement patterns to establish object contact with their digits, and (2) synchronize the subsequent force development and temporal coordination of the task. Thus while the complexity of the task requires control mechanisms beyond those seen in two-finger precision grasping, there are strategies to simplify the complex task of the initiation and development of fingertip forces in whole-hand grasping.     

Synaptic potentials evoked by convergent somatosensory and corticocortical inputs in raccoon somatosensory cortex: substrates for plasticity.

1. "Unmasking" of weak synaptic connections has been suggested as a mechanism for the early changes in cortical topographic maps that follow alterations of sensory activity. For such a mechanism to operate, convergent sensory inputs must already exist in the normal cortex. 2. We tested for topographic and cross-modality convergence in primary somatosensory cortex of raccoon. The representation of glabrous skin of forepaw digits was chosen because, even though it is dominated by inputs from the glabrous skin of a single digit, it nevertheless comes to respond to stimulation of other digits when, e.g., a digit is removed. 3. Intracellular recordings were made from 109 neurons in the representation of glabrous skin of digit 4. Neurons were tested for somatosensory inputs with electrical and natural stimulation of digits. 4. Excitatory postsynaptic potentials (EPSPs) were evoked in 100% of the neurons (109/109) by electrical stimulation of glabrous skin of digit 4, and in 79% (31 of 39) by vibrotactile stimulation. 5. Glabrous skin of digit 4 was not the sole source of somatosensory inputs. A minority of neurons generated EPSPs after electrical stimulation of hairy skin of digit 4 (10 of 98 neurons, 10%). Electrical stimulation of digits 3 or 5 evoked EPSPs in 22 of 103 neurons (21%). Natural stimulation (vibrotactile or hair bending) was also effective in most of these latter cases (digit 3, 6/7; digit 5, 9/10). 6. Intracortical microstimulation of the "heterogeneous zone" was used to test for corticocortical connections to neurons in the glabrous zone.(ABSTRACT TRUNCATED AT 250 WORDS)