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61.
无创正压通气治疗重症急性心源性肺水肿临床研究   总被引:5,自引:0,他引:5  
目的评价无创通气模式持续气道正压(cPAP)和双水平气道正压(BiPAP)通气在急性心源性肺水肿治疗中的作用。方法我院急诊科收治的60例严重急性心源性肺水肿,均合并酸中毒(pH〈7.35),随机分为3组,即常规吸氧组,CPAP组(10cmH2O)和BiPAP组(IPAP=15cmH2O,EPAP=5H2O)。后两者采用伟康医疗公司的S/T30型呼吸机通气。以院内2小时抢救成功率和幸存出院率评价治疗效果。结果抢救成功率(2小时治疗结束时呼吸频率〈23次/min,SaO2〉90%,动脉血pH〉7.35,酸中毒恢复):对照组3例(15%),CPAP组7例(35%),BiPAP组9例(45%),P=0.116;幸存出院:对照组14例(70%),CPAP组20例(100%),BiPAP组15例(75%),P=0.029(采用Fisher's检验)。结论研究结果显示:急性心源性肺水肿合并酸中毒者,采用CPAP治疗幸存出院率更高,而不是BiPAP和常规吸氧组。院内生存率与早期生理变化间无相关。早期实施无创通气,使插管率降低。  相似文献   
62.
Differentiating hepatic portal venous gas (HPVG) and pneumobilia on the CT scan can be accomplished by comparing the pattern of intrahepatic air spread. HPVG can be an indicator of significant intra‐abdominal pathology and bowel ischaemia is the most common causative etiology for HPVG.  相似文献   
63.
目的探讨戊二酸尿症1型的临床特征和诊断思路。方法对3例戊二酸尿症1型患儿的临床资料进行分析。结果3例患儿均表现为感染或惊厥后发育倒退,其中大头畸形一例,不明原因的硬膜下积液一例。结论戊二酸尿症1型临床表现无特异性,但感染或惊厥后发育倒退、大头畸形、不明原因的硬膜下积液时是其主要特征,尿有机酸分析是诊断的重要依据。  相似文献   
64.
目的:分别采用高效液相色谱法和气相色谱质谱联用法测定白念珠菌麦角甾醇含量,并对这两种方法进行比较。方法:采用浓度梯度递增法诱导白念珠菌耐药株,采用KONT真菌显色MIC药敏系统鉴定耐药性。构建6、12、24h生物被膜,采用高效液相色谱法和气相色谱质谱联用法测定麦角甾醇含量。结果:高效液相色谱法检测出麦角甾醇含量,最低检出浓度为0.05mg/L,而气相色谱质谱联用法未检测出麦角甾醇含量。结论:高效液相色谱法能准确测定白念珠菌麦角甾醇含量。与气相色谱质谱联用法比较,高效液相色谱法简单、高效和可靠。  相似文献   
65.
66.
The estimation of the postmortem interval (PMI) is always a key issue in forensic science. Although many attempts based on metabolomics approaches have been proven to be feasible and accurate for PMI estimation, there have been no reports regarding the determination of the PMI in acute dichlorvos (DDVP) poisoning. In this study, all rats were killed by acute DDVP poisoning at a dose three fold the oral LD50 (240 mg/kg). Gas chromatography-mass spectrometry (GC/MS) was applied to investigate the metabolic profiling of blood samples at various times after death up to 72 h. A total of 39 metabolites were found to be associated with PMI, and the combinations of various numbers of metabolites were used to establish support vector regression (SVR) models to investigate the PMI. The SVR model constructed by 23 metabolites had a minimum mean squared error (MSE) of 5.49 h for the training set. Then, the SVR model was validated by prediction set with an MSE of 10.33 h, suggesting good predictive ability of the model for investigating the PMI. The findings demonstrated the great potential of GC/MS-based metabolomics combined with the SVR model in determining the PMI of DDVP poisoned rats and provided an experimental basis for the application of this approach in investigating the PMI of other toxicants.  相似文献   
67.
Prieto AL  O'Dell S  Varnum B  Lai C 《Neuroscience》2007,150(2):319-334
Protein phosphorylation serves as a critical biochemical regulator of short-term and long-term synaptic plasticity. Receptor protein tyrosine kinases (RPTKs) including members of the trk, eph and erbB subfamilies have been shown to modulate signaling cascades that influence synaptic function in the central nervous system (CNS). Tyro3 is one of three RPTKs belonging to the "TAM" receptor family, which also includes Axl and Mer. Tyro3 is the most widely expressed of these receptors in the CNS. Despite recent advances suggesting roles for members of this receptor family in the reproductive and immune systems, their functions in the CNS remain largely unexplored. In an effort to elucidate the roles of Tyro3 and its ligand, the protein growth arrest-specific gene6 (Gas6) in the hippocampus and cortex, we performed a detailed study of the localization and signaling of Tyro3 polypeptides in rat hippocampal and cortical neurons. Tyro3 was readily detected in dendrites and in the soma where it was distributed in a punctate pattern. Tyro3 exhibited only a limited level of co-localization with postsynaptic density protein-95 (PSD-95), suggesting that while located within dendrites, it was not confined to the postsynaptic compartment. In addition, Tyro3 was also identified in the axons and growth cones of immature neurons. The prominent expression of Tyro3 in dendrites suggested that it may be capable of modulating signaling pathways triggered by synaptic transmission. We have provided evidence in support of this role by demonstrating that Gas6 induced the phosphorylation of Tyro3 in cortical neurons in vitro, resulting in the recruitment of the mitogen-activated protein kinase (MAPK) and the phosphoinositide-3 kinase (PI(3)K) signaling pathways. As these pathways play critical roles in the induction of hippocampal long-term potentiation (LTP), these findings suggest that Tyro3 signaling may influence synaptic plasticity in the dendritic compartment of hippocampal and cortical neurons.  相似文献   
68.
The post-mortem use of modern imaging techniques such as multislice computed tomography (MSCT) is becoming increasingly important as an aid for conventional autopsy. This article presents a case of a 4-month-old boy who died from sudden infant death syndrome (SIDS) with intravascular gas after an intraosseus medication application documented by post-mortem MSCT. It is most likely that the gas entered the body during resuscitation. This case emphasises the advantage of post-mortem imaging as a complementary aid for the autopsy. We conclude that during emergency treatment, the medical staff should be aware of the possibility of causing a gas embolism following intraosseus medication. Resuscitation with an inserted, disconnected intraosseous needle should be avoided.  相似文献   
69.
目的建立气相色谱(GC)法测定止痒洗剂中苯酚和薄荷脑的含量方法,为止痒洗剂质量控制提供有效的分析手段。方法色谱柱:以HP-5(95%二甲基-5%二苯基聚硅氧烷,0.25 mm×30.0 m)毛细管柱为色谱柱;柱温为60℃;以8℃/min速率升温至160℃,保温10 min,进样口温度180℃,FID检测器,检测器温度300℃。空气流速为300 ml/min,分流比为20∶1。进样量1μl。结果苯酚和薄荷脑的线性范围分别是0.45~9 mg/ml和0.25~5 mg/ml,回归方程分别是A=1.476 9C-0.109 9(r=0.999 9)和A=1.393 7C-0.095 9(r=0.999 9)。苯酚和薄荷脑的平均回收率分别为100.6%(RSD=0.73%)和100.8%[相对标准偏差(RSD)=0.76%]。结论该方法简单,结果准确可靠,可用于止痒洗剂中苯酚和薄荷脑的含量测定。  相似文献   
70.
Providing partial respiratory assistance by removing carbon dioxide (CO2) can improve clinical outcomes in patients suffering from acute exacerbations of chronic obstructive pulmonary disease and acute respiratory distress syndrome. An intravenous respiratory assist device with a small (25 Fr) insertion diameter eliminates the complexity and potential complications associated with external blood circuitry and can be inserted by nonspecialized surgeons. The impeller percutaneous respiratory assist catheter (IPRAC) is a highly efficient CO2 removal device for percutaneous insertion to the vena cava via the right jugular or right femoral vein that utilizes an array of impellers rotating within a hollow‐fiber membrane bundle to enhance gas exchange. The objective of this study was to evaluate the effects of new impeller designs and impeller spacing on gas exchange in the IPRAC using computational fluid dynamics (CFD) and in vitro deionized water gas exchange testing. A CFD gas exchange and flow model was developed to guide a progressive impeller design process. Six impeller blade geometries were designed and tested in vitro in an IPRAC device with 2‐ or 10‐mm axial spacing and varying numbers of blades (2–5). The maximum CO2 removal efficiency (exchange per unit surface area) achieved was 573 ± 8 mL/min/m2 (40.1 mL/min absolute). The gas exchange rate was found to be largely independent of blade design and number of blades for the impellers tested but increased significantly (5–10%) with reduced axial spacing allowing for additional shaft impellers (23 vs. 14). CFD gas exchange predictions were within 2–13% of experimental values and accurately predicted the relative improvement with impellers at 2‐ versus 10‐mm axial spacing. The ability of CFD simulation to accurately forecast the effects of influential design parameters suggests it can be used to identify impeller traits that profoundly affect facilitated gas exchange.  相似文献   
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