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21.
Jill L. Oswalt MD Jerris R. Hedges MD Betsy E. Soifer MD PhD Daniel K. Lowe MD 《The American journal of emergency medicine》1992,10(6):511-514
The timing of trauma patient intubation is dependent on clinical presentation and clinician judgment. We sought to correlate the timing of intubation with the presenting of physiologic parameters and clinical outcome to identify potential quality assurance audit filters. Patients (n = 82) were grouped by timing of intubation: PREHOSPITAL, paramedic intubation; IMMEDIATE, within 10 minutes of arrival; DELAYED, beyond 10 minutes but within 2 hours of arrival; and NONURGENT, beyond 2 hours or at the time of surgery. While mean revised trauma scores and Glasgow Coma Scale (GCS) scores differed for the groups, the mean length of hospital stay and the incidence of aspiration pneumonia were not significantly different. In the DELAYED group, 80% of those who developed aspiration pneumonia had a GCS < or = 13. Patients in the NONURGENT group were older and commonly presented with tachypnea. The survival rate for the NONURGENT group was lower than predicted by the TRISS method (P = .004). A GCS < or = 13 and age greater than 50 years with presenting respiratory rates of more than 25 breaths/min represent potential trauma intubation audit filters. 相似文献
22.
Gaston R Vergara William F Wallace Kenneth R Bennett 《Catheterization and cardiovascular interventions》2007,69(2):300-302
Thromboembolic disease accounts for thousands of hospitalizations every year in the US. Its primary management consists of anticoagulation. However, in certain instances this may be contraindicated or not sufficient. Mechanic occlusion of the inferior vena cava (IVC) becomes then a viable alternative. In this case a 35-year-old man presented with a saddle pulmonary embolus but was unable to be anticoagulated due to intestinal bleed. A removable IVC filter was then placed. The filter spontaneously migrated into the right atrium causing severe tricuspid regurgitation, perforation of the atrial wall, and cardiac tamponade. The device was successfully retrieved percutaneously and the patient discharged from the hospital in stable condition. This case illustrates the potentially lethal complications associated with the use of IVC filters, as well as the possibility to percutaneously recover them from within the right atrium. 相似文献
23.
包红华 《中国医药工业杂志》2003,34(10):528-529
在泛酸钙生产过程中,采用精密微孔过滤机代替离心机与快开式平板过滤器的生产工艺,提高了产品产量和质量,减少了溶剂的损失。 相似文献
24.
介绍一种操作简单、成本较低、便于医生确定靶肌肉的肌电引导治疗仪.该仪器经过临床初步试验,效果良好. 相似文献
25.
目的 探讨用改进的倒谱方法估计平均骨小梁间距(mean trabecular bone spacing,MTBS)的可行性.方法 提出了一种基于反向滤波器的改进的倒谱分析方法用于估计MTBS,并将该方法应用于仿真及离体牛胫骨松质骨中的实验信号.结果 改进的倒谱方法能有效减少超声换能器脉冲响应和组织散射特性对倒谱的干扰,而且实现简单,计算量小.结论 相比于传统的倒谱方法,改进的倒谱方法在估计MTBS时, 对弥散散射和噪声有更强的鲁棒性,因此估计MTBS的精度更高. 相似文献
26.
Bernhard J. Connemann Heidrun Busche Jürgen Kreusch Helmut H. Wolff 《Skin research and technology》1996,2(1):40-48
Background/aims: Quantitative measurement of skin roughness has proved to be a valuable tool in the efficacy-control of external applications, but it suffers from not yielding easily comparable results. The most important sources of inter-observer variability are high-pass filters used to separate roughness and waviness, and low-pass filters which result from the finite resolution of the instrument or from the finite sampling interval of digital measurement. In the present study, the effects of high-pass filters and sampling intervals on the roughness measured were investigated. Methods: Dynamically focusing optical profilometry was used to measure the surfaces of negative replicas of healthy human skin. High-pass cut-off wavelengths and sampling intervals were varied systematically. Results/conclusions: Virtually unbiased estimates for the roughness parameters K, Sk, Rq, and Ra can be obtained using sampling intervals of 40 or even 80 μm. Regarding these roughness parameters, it is far better to do more scans than to shorten the sampling interval. The roughness parameters Rz, Rp, Rt, Rpm, Rmax, Pt, on the other hand are very sensitive to the influence of the sampling interval; to achieve satisfying estimates, the sampling interval should be no longer than 2 to 5 urn; as an important parameter’of the measurement, it is worthy of remark and should always be indicated. The way the mean square roughness Rq depends on the cut-off wavelength is not well described by the Sayles-Thomas-relation Rq~λc0.5. If the power-spectrum |h*(v)|2 approximates sufficiently to a power law, |h*(v)|2~vδ, a better estimate is given by Rq~λcγ with γ=-(δ+1)/2. In many cases, γ=1 or Rq~λc will suffice. 相似文献
27.
Measurements of IgE levels in the blood of neonates were investigated using filter paper for blood collection in mass screening of congenital metabolic disorders. Time-resolved fluoroimmunometric assay system for the measurement of filter paper blood IgE levels was also studied. In an analysis of the present results, IgE values of at least 0.015U/ml, the measurement limit, were considered as high. High IgE levels in filter paper blood were seen in 28 (7.2%) of the 389 cases. When the relation with serum IgE levels at 18 months of age was investigated in 134 of 389 subjects, high serum IgE levels were also found in about 86.7% of the subjects with high IgE levels in filter paper blood. In addition, when the relation between family history of atopic disease and presence of atopic disease in the first 18 months of age was investigated in 203 of the 389 subjects, about 90% of the subjects with a family history of atopic disease and high IgE levels in filter paper blood developed atopic disease. Since filter paper blood is routinely collected in Japan, IgE levels in this blood should be widely checked for the prediction of onset of atopic disease in infants. 相似文献
28.
Summary A simple organ culture method for culturing embryonic skin was developed. A piece of skin with a part of the neural tube from mouse embryo (11 to 12 d) was placed on a 25 mm d membrane filter. The filter was folded to wrap the explant and inserted into glass tubing. The explant and filter in the glass tubing were placed in a rotating tissue culture tube containing 5 ml culture medium (Ham's F12 supplemented with 15 to 20% fetal bovine serum) and filled with a mixture of 95% air:5% CO2. In explants cultured for 6 d fully differentiated melanocytes were observed in the epidermis. 相似文献
29.
Fluid Flow through Filtering Appendages of Insects 总被引:4,自引:0,他引:4
Many organisms use structures composed of arrays of cylindersto capture particulate food or molecules form the water or airaround them. The performance of such filters depends on thevelocity of fluid movement through them; hence, mathematicalmodels of flow through fibrous structures can provide insightsabout the functional morphology of biological filters. In thispaper, the authors address the case of feather-like biologicalfilters of finite width and assess several possible models forfluid motion through them by comparing model predictions withobservational data. Two examples of insect appendages are considered:the cephalic fans of black fly aquatic larvae that capture particulatefood and the antennae of adult male moths that catch sex-attractantmolecules released by female moths. The results suggest thatflow through such structures can be much slower than ambientcurrents, that the finest hairs in the structure are the morphologicalfeatures with the greatest effect on leakiness, and that thevelocity of movement (or of ambient flow), as well as the morphologyof such filters, can be critical in determining their performance. 相似文献