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1.
Comparisons of a shoemark with a shoesole (and standards) sometimes lead to associations based on air bubbles (among other manufacturing or acquired characteristics). Today, the assessment of the evidential value of air bubbles coincidences relies largely upon the examiner's experience and/or follows sometimes a verification based on the examination of a small number of analogous pairs collected for the case at hand. Statistical data related to the occurrence and characteristics of air bubbles on shoesoles in an attempt to model the potential variability have been gathered. Seventy-one pairs of shoes with the same design, brand, model and size were obtained. Right and left soles were photographed. An image-processing algorithm was developed to allow the systematic acquisition of data such as: (1) the number of air bubbles on the sole and around given structural elements; (2) the measure of air bubbles characteristics such as their surface and position. These data allow a discussion of the assessment of the probability of finding on shoesoles (same design, brand, model and size) a certain number of air bubbles on a surface with the same positions and morphology.  相似文献   

2.
The potential of venous air embolism ascending retrograde to the brain   总被引:2,自引:0,他引:2  
A bench study was performed to investigate the potential of air bubbles entering a central vein via a central venous catheter to ascend retrograde to the brain. The results support the hypothesis that air bubbles may rise retrograde against the venous blood flow, depending on bubble size, central vein diameter and cardiac output. A review of radiological findings in published case reports indicates that the occurrence of retrograde cerebral air embolism is underestimated.  相似文献   

3.
The wrappings and contents of 683 drug containers (bubbles) seized from 154 street dealers have been analysed since 2001, when the law enforcement policy in Hamburg, Germany, allowed the application of emetics to be used by so-called body stuffers for the recovery of swallowed drug packages. Of the bubbles recovered 96% contained cocaine. Cases of intoxication have not yet been observed but a 20-year-old man with a previously unknown toxic cardiomyopathy died 3 days after a sudden cardiac arrest which followed the forced application of ipecacuanha via correctly placed nasogastral tube.  相似文献   

4.
There are few reported cases of death attributed to retrograde cerebral air embolism from central venous catheter. The pathophysiological mechanism and the necessary conditions are not fully understood, also because of missing experimental data. We performed experimental simulation while working on a possible case of retrograde cerebral air embolism. A hermetic system consisting of two containers connected to each other and to an electric pump by means of rubber hoses was built. In this system, a fluid (water and blood) could continuously flow under conditions similar to those of the common jugular vein. The part of the system representing the jugular vein could be freely positioned at angles between 0 and 90°. A central venous catheter was inserted into this part. After disconnection, the behavior of the air bubbles entering the hose through the tip of the catheter was evaluated at different positions. At angles between 0 and 45°, the air bubbles followed the fluid flow. At angles >45°, the air bubbles showed the tendency to flow upstream; this phenomenon was more evident the more vertically the hose was located. We were able to demonstrate that a retrograde air embolism can be caused by a disconnected catheter and is even more likely if the neck is in a vertical position.  相似文献   

5.
Significance of anastomoses in the lung in microembolism   总被引:2,自引:0,他引:2  
The importance is demonstrated of anastomoses between the pulmonary artery and the bronchial artery as well as of the arteriovenous anastomoses that arise from these in microembolism. In cases of air embolism, microembolism in the lungs is seldom. Therefore, there must be particular circumstances that make it possible for little air bubbles to pass the anastomoses from the pulmonary artery via the bronchial artery and the arteriovenous anastomoses into the bronchial vein. The pressure in the bronchial artery must decrease. Under these conditions, blood is shunted from the pulmonary artery to the bronchial artery and little air bubbles can pass via the above-mentioned anastomoses into the pulmonary vein.  相似文献   

6.
宋华安 《法人》2009,(11):60-62
创业板新股高价发行,从一级市场开始就充满了大量泡沫,要防范创业板股票的投资风险,维护其平稳运行,仅按照“通知精神”和严密监控首日交易显然是不够的  相似文献   

7.
目的建立减少DNA低体积扩增过程中产生气泡的方法。方法采用激光显微切割技术、PALM系统收集目标细胞,并在1μL~1.5μL低体积扩增样本,加入扩增液0.7μL~0.8μL。结果低体积扩增反应中的失败位点比例为2.3%,比常规反应位点时常会产生气泡导致该位点样本扩增失败且达30%以上的比例显著降低。结论低体积扩增方法可以减少或克服扩增过程中气泡的产生,提高扩增成功率。  相似文献   

8.
The vital reaction to heat-induced thrombosis is discussed here using a case of sudden death in the Sauna. The dead body was lying for about one hour in the heat (90 degrees C). Beside the beginning formation of bubbles there was subcutaneous blood vessel exposition, especially in parts outside of the Livor mortis. The cause of death was viral infection with florid Myocarditis.  相似文献   

9.
英国南海公司与清末轮船招商局都曾出现股市泡沫,官方的制度回应不但未能阻止泡沫化,还给证券市场带来深远的负面影响。在承认人的理性存在有限性之前提下,比对两家企业的史实,探求制度如何在不同历史背景下对股市泡沫作出有效回应,更易于发现法制对于股票交易的意义所在。  相似文献   

10.
Interstitial emphysema and pulmonic hemorrhage alone are not the causes of pulmonic air embolism. The conditions making the entrance of air from the lungs to the vessels of pulmonary circulation are obviously present only if the expiration pressure is suddenly strongly elevated. Based on this point of view, investigations were performed in autopsy cases--falls from a height, being run over, a gunshot in the abdomen. We have succeeded in proving the entrance of air into capillaries and branches of the pulmonary vein. The precipitation of thrombocytes at the margin of large air bubbles in pulmonary veins shows the finding of air in the vessels as a vital or supravital reaction.  相似文献   

11.
检察理论研究在取得一定成果的同时,也存在着不少问题,如较强的部门化倾向、意识形态化话语较多、研究范式以证成性为主等。表面繁荣的背后暴露出学术评价量化机制的某些弊端。应以开放的姿态建构独立自主的检察理论研究体系,把握好历史与逻辑的辩证统一。  相似文献   

12.
Abstract: Aspiration of blood is a phenomenon observed in violent and natural death scenarios. Bloodstain patterns evolving from expectoration of aspired blood may look suspicious of a violent genesis and thus mislead crime scene investigators. In the present case, a woman was found lying in a pool of blood on the kitchen floor. Furthermore, bloodstains covered her face, clothing, and surrounding furniture and walls. Bloodstain pattern analysis and medicolegal inspection of the suspected scene of crime were carried out and revealed dispersed stains with enclosed gas bubbles in the absence of signs of physical violence leading to the assessment of a natural manner of death. The bloodstains were attributed to expiration of blood because of an internal bleeding. Medicolegal autopsy confirmed the on‐site diagnosis as a fatal esophageal varix rupture was found.  相似文献   

13.
This pilot study examined teeth subjected to extreme heat under laboratory conditions, and the subsequent effect of decalcification and histologic processing. Physical and microscopic findings were evaluated in relation to temperature and duration of thermal insult. Microscopic examination following decalcification and histologic processing revealed changes including severe tissue fragmentation, vapor bubbles within dentinal tubules, altered histologic staining, charring and tissue shrinkage. Dentin appeared to be the most reliable microscopic identifier of incinerated dental tissues. Temperatures above 600 degrees C strongly predicted tooth disintegration following decalcification. This finding has implications in incineration cases where histologic evidence must be maintained and examined intact.  相似文献   

14.
An iatrogenic cause of air embolism with a fatal outcome is reported that occurred in a case in which arthroscopy of the knee had been carried out. Even after worldwide use of arthroscopy for many years, this complication has never been seen until now. At autopsy, when air bubbles were observed in the right heart chamber and in the vena cava inferior, only the knee joint was taken into consideration as the air-access route. The access of air was detected by means of arthroscopy on the corpse, combined with a special autopsy technique and shown experimentally. Insufflated air had entered via a fracture of the tibial articular surface and then passed through the spongiosa into the femoral vein. These findings are of far-reaching clinical consequence because the indication for arthroscopy by gas insufflation must be reconsidered again. Finally, the medicolegal aspects of such an incident are discussed.  相似文献   

15.
The purpose of this study was to evaluate two types of impression materials which were frequently used for casting three‐dimensional tool marks in China, namely (i) dental impression material and (ii) special elastomeric impression material for tool mark casting. The two different elastomeric impression materials were compared under equal conditions. The parameters measured were dimensional accuracies, the number of air bubbles, the ease of use, and the sharpness and quality of the individual characteristics present on casts. The results showed that dental impression material had the advantage of special elastomeric impression material in casting tool marks in crime scenes; hence, it combined ease of use, dimensional accuracy, sharpness and high quality.  相似文献   

16.
Dental stone is used as the major material for recovering three-dimensional shoeprints and tire tracks from crime scenes. The procedure for using dental stone sparsely changed over the years. There are two common methods for mixing dental stone: (i) a premeasured amount of dental stone is put in a zip-lock bag to which water is added, and (ii) the water and dental stone are mixed in a bucket. We suggest a novel rapid and efficient method of mixing dental stone and water in a bottle. These methods were compared at equal conditions. The parameters measured were the number of air bubbles, the strength of the cast, the ease of use, and the sharpness and quality of the accidental characteristics present in the cast. The proposed bottle method has the advantages of both the bucket and the zip-lock methods hence it combines strength, sharpness, high quality, and ease of use.  相似文献   

17.
In Hannover/Germany in 1976 a so called "Society for Regenerative Hyperbaric Therapy" (Gesellschaft für Regenerative Uberdruck-Therapie) subjected 20 patients within two coupled multi-place chambers to a simulated hyperbaric environment, equivalent to a maximum of 4 ata, followed usually by gradual reductions of the pressure. The patients were of an average age of 67.2 years and were afflicted by various disorders. During one of the "dives" a patient developed air embolism of the central nervous system. During ensuing confusion of the chamber was opened suddenly, with resultant explosive reduction of the high pressure. This resulted in five letal accidents of decompression sickness. Post mortem examination revealed diffuse distribution of gas bubbles throughout the entire body. By elecronmicroscopy each bubble was covered by an osmiophilic coat. Post mortem findings are discussed and correlated with well-known and new clinical symptomes. These observations present for the first time fatal accidents of decompression sickness in humans, associated with hyperbaric air-therapy.  相似文献   

18.
Increased use of water search dogs for detecting submerged bodies has created the need for a better understanding of scent emanating from the bodies and how it transits the water to the dog's nose. A review of recent literature identifies likely scent sources, potential scent transport processes, and research needs. Scent sources include gases in bubbles or dissolved in the water, liquids as buoyant plumes and droplets or dissolved in the water, and solids consisting of buoyant particulates with secretions, bacteria, and body fluids. Potential transport processes through the water include buoyancy, entrainment, and turbulence. Transport processes from the water surface into the air include volatilization and evaporation enhanced by bubble bursting, breaking waves, splashing, and wind spray. Implications for the use of water search dogs are examined. Observations of submerged, decomposing bodies are needed to quantify the physical and chemical characteristics of the scent and scent transport processes.  相似文献   

19.
A total of 510 hairs with Widy's zones from 6 cases of poisoning were microscopically studied, both with light from above and from below. In every instance when the light came from below the zones appeared lighter in colour when pressure was applied. This lighting-up in color was reversible. This effect is incompatible with the opinion, still prevalent today, that the zones may be explained by hyperpigmentation. Quite frequently the zones became lighter during a prolonged exposure to water while simultaneously gas bubbles developed. However, even after extensive exposure to thioglycolic acid the zones did not disappear entirely in all cases. We explain these phenomena with the total reflection of the light at numerous bordering surface of substances with differing indices of fraction. We measured the thallium concentration in the urine and in the hair during the time interval between two thallium poisonings with the result that in those parts of the hair which had grown during a period when no thallium level was measured in the urine we found discernibly to strongly increased thallium concentrations. The results of our study indicate that, considering the most recent knowledge, proof of multiple thallium poisoning ought not to be attempted by means of fractional chemical investigation of the hair alone.  相似文献   

20.
The alterations in the hair roots discovered by Widy in 1956 were interpreted as accumulations of pigment which form as a consequence of a catalytic action of the poison. The goal of the present investigation was to clarify the structure of these inclusions. Hair from the heads of six victims who were involved in the poisoning of Würzburg medical students in January 1983 was available as investigation material. In the investigation in transmitted light and in polarized light, the black zones typical for thallium intoxication were found filling to varying extents the root and hair shaft near the root. Their intensity corresponded to the degree of severity of the intoxication. When examined under reflected light, the inclusions were shown up with a white color. They thus showed the same optical behavior as the air-filled medullary strand of normal hairs. This indicates that gaseous constituents are involved. This hypothesis could be confirmed by further investigations. After mechanical damage to the hair (pressing under high pressure), the gaseous inclusions disappeared and with them the "thallium strip." The same effect was attained by the chemical action of various acids, embedding agents, and dye solutions. This process was especially rapid after exposure to thioglycolic acid; the escape of the gas bubbles can be directly observed here. Scanning electron microscopic investigations on transverse sections of hair revealed a loosening of the spindle-shaped elements of the fiber layer as signs of structural disturbance. The gaseous constituents in thallium hair arise as the result of a trophic disorder in keratin formation. The structural alteration due to this leads to alopecia.  相似文献   

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