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241.
目的探讨营养不良性肺水肿大鼠肺泡液体清除功能的变化及其机制。方法制备营养不良性肺水肿大鼠动物模型,分别于48h和120h测定大鼠肺泡液体清除率(AFC)、总肺水量(TLW)和肺血管外水量(EVLW)。将钠通道阻断剂氨氯毗眯、Na-K-ATP酶阻断剂畦巴因及β2受体激动剂特布他林分别灌注到正常及禁食120h大鼠的肺泡腔内,测定AFC的变化。结果大鼠禁食48hAFC(19.7±3.22%)与正常大鼠AFC(18.5±2.21%)比较没有明显变化;120h时AFC(9.50±2.19%)明显降低。氨氯吡咪、哇巴因明显降低营养不良性肺水肿大鼠AFC(P<0.05),特布他林对营养不良性肺水肿大鼠AFC的作用与对照组大鼠比较差异无显著性(P>0.05)。结论营养不良性肺水肿与钠通道及Na-K-ATP酶及的活性被抑制,导致肺泡液体清除能力降低有关。  相似文献   
242.
The recently discovered contamination of oral rotavirus vaccines led to exposure of millions of infants to porcine circovirus (PCV). PCV was not detected by conventional virus screening tests. Regulatory agencies expect exclusion of adventitious viruses from biological products. Therefore, methods for inactivation/removal of viruses have to be implemented as an additional safety barrier whenever feasible. However, inactivation or removal of PCV is difficult. PCV is highly resistant to widely used physicochemical inactivation procedures. Circoviruses such as PCV are the smallest viruses known and are not expected to be effectively removed by currently‐used virus filters due to the small size of the circovirus particles. Anion exchange chromatography such as Q Sepharose® Fast Flow (QSFF) has been shown to effectively remove a range of viruses including parvoviruses. In this study, we investigated PCV1 removal by virus filtration and by QSFF chromatography. As expected, PCV1 could not be effectively removed by virus filtration. However, PCV1 could be effectively removed by QSFF as used during the purification of monoclonal antibodies (mAbs) and a log10 reduction value (LRV) of 4.12 was obtained. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:1464–1471, 2013  相似文献   
243.
目的:探讨血清降钙素原(procalcitonin,PCT)、乳酸清除率及危重疾病评分(Acute Physiology and Chronic Health EvaluationⅡ,APACHEⅡ)对脓毒症预后的评估价值。方法:选择2011年2月~2013年2月期间我院收治的脓毒症休克及严重脓毒症患者92例,其中脓毒症休克37例,严重脓毒症者55例;存活60例,死亡32例。对本组患者血清PCT、乳酸清除率及APACHEⅡ进行分析,探讨以上指标对其预后的评定价值。结果:1死亡组血清PCT、APACHEⅡ、乳酸分值均大于存活组,左心射血分数(Left ventricular ejection fraction,LVEF)及早期乳酸清除率小于存活组,对比具有统计学意义(P0.01或P0.05);2脓毒性休克组血清PCT、APACHEⅡ、乳酸分值均大于严重脓毒症组,LVEF及早期乳酸清除率小于严重脓毒症组,对比具有统计学意义(P0.01或P0.05);3本组乳酸与APACHEⅡ呈正相关性(P0.01),早期乳酸清除率与APACHEⅡ呈负相关性(P0.01)。结论:PCT、乳酸清除率及APACHEⅡ评分可以作为脓毒血症预后的有效评估指标,通过对PCT、乳酸清除率及APACHEⅡ评分监测以便尽早采取积极的治疗措施,改善预后情况。  相似文献   
244.
《IRBM》2014,35(3):158-163
The main objective of this paper was to assess the performance of the ambulatory device μHematron to measure indirectly skin blood flow relative to the well-established Laser Doppler flowmetry method. The μHematron device is dedicated to the non-invasive measurement of effective thermal conductivity of living tissues, based on the thermal clearance method. Its major advantage is its ambulatory functionality, as available methods for evaluation of microcirculatory activity are non-ambulatory methods. An experiment was conducted on ten healthy women exposed for one hour in three different thermal environments (22 °C, 25 °C and 30 °C). Skin microcirculatory activity was analyzed after an acclimatization period of 30 minutes. The time between each exposure was at least one hour. Performances of the μHematron device were assessed and a comparative study with a laser Doppler perfusion monitor (LDPM) was performed. Good correlation coefficients between the two devices (r = 0.71 at T1 = 22 °C, r = 0.77 at T2 = 25 °C and r = 0.83 at T3 = 30 °C) were obtained while the LDPM signal was filtered by a low pass filter (0.1 Hz). These results showed that continuous monitoring of effective thermal conductivity was possible in neutral and warm ambiences. Then, the μHematron device could be considered as a complementary tool to Doppler techniques for the investigation of skin blood flow, when ambulatory conditions are required.  相似文献   
245.
目的:探讨颅脑外伤手术中出现迟发性硬膜外血肿(DEDH)的原因及预防对策。方法:回顾性分析10例手术过程中DEDH发生的原因、现象,治疗过程、结果及预后等临床资料。结果:10例DEDH发生于伤后72h以内、手术减压后,6例伴有颅骨骨折,3例伴静脉窦损伤。7例术前甘露醇用量超过500ml,经手术清除和保守治疗,死亡1例。结论:颅骨骨折和颅内静脉窦损伤是DEDH发生的病理基础,减压手术和甘露醇强力脱水治疗是其发生的促进因素,GCS评分和血肿持续时间与预后密切相关。  相似文献   
246.
目的:评价建立急诊绿色通道对救治颅脑外伤患者的价值.方法:采用回顾性分析方法,收集我院2007年1月~2012年1月救治的颅脑外伤患者199例,其中急诊绿色通道组111例(A组)和非急诊绿色通道组88例(B组)的救治情况进行比较,分析两组救治的疗效、死亡率及预后.结果:199例颅脑外伤患者中,绿色通道组(A组)111例(55.78%),死亡26例(23.42%),对照组88例(44.22%),死亡30例(34.09%).A组的有效治疗时间较B组明显缩短,差异有统计学意义(0.01<P<0.05);A组硬膜外血肿(33例)的术前血肿量少于B组(30例),预后较B组好,差异有统计学意义(0.01<P<0.05);A组的中重型颅脑外伤的死亡率明显低于B组,差异有统计学意义(0.01<P<0.05),两组特重性颅脑外伤的死亡率仍较高,差异无统计学意义(P>0.05).结论:急诊绿色通道可缩短颅脑外伤患者救治等待时间,改善中重型颅脑外伤患者的预后.  相似文献   
247.
248.
Inhibition of Mussel Suspension Feeding by Surfactants of Three Classes   总被引:1,自引:0,他引:1  
Effects of three surfactants on the filtration rates by marine mussels were studied. The xenobiotics tested represented anionic, cationic and non-ionic surfactants (tetradecyltrimethylammonium bromide, a representative of a class of cationic surfactants; sodium dodecyl sulphate, a representative of anionic alkyl sulfates; and Triton X-100, a representative of non-ionic hydroxyethylated alkyl phenols). All three surfactants inhibited the clearance rates. The significance of the results for the ecology of marine ecosystems is discussed.  相似文献   
249.
The human tracheobronchial tree surface is covered with mucus. A healthy mucus is a heterogeneous material flowing toward the esophagus and a major defense actor against local pathogen proliferation and pollutant deposition. An alteration of mucus or its environment such as in cystic fibrosis dramatically impacts the mucociliary clearance. In the present study, we investigate the mechanical organization and the physics of such mucus in human lungs by means of a joint experimental and numerical work. In particular, we focus on the influence of the shear-thinning mucus mobilized by a ciliated epithelium for mucociliary clearance. The proposed robust numerical method is able to manage variations of more than 5 orders of magnitude in the shear rate and viscosity. It leads to a cartography that allows to discuss major issues on defective mucociliary clearance in cystic fibrosis. Furthermore, the computational rheological analysis based on measurements shows that cystic fibrosis shear-thinning mucus tends to aggregate in regions of lower clearance. Yet, a rarefaction of periciliary fluid has a greater impact than the mucus shear-thinning effects.  相似文献   
250.
Coloniality in the phylum Rotifera   总被引:3,自引:1,他引:2  
Coloniality in the phylum Rotifera is defined and reviewed. Only two families of rotifers contain truly colonial forms: Flosculariidae and Conochilidae (order Gnesiotrocha, suborder Flosculariacea). Most species form intraspecific colonies ranging in size from a few to about 200 individuals, but species that produce enormous colonies (> 1000 individuals) are also known. All seven genera of the Flosculariidae contain species that form colonies to widely varying degrees (Beauchampia, Floscularia, Lacinularia, Limnias, Octotrocha, Ptygura, Sinantherina). All four species of the monogenetic Conochilidae (Conochilus) are colonial, but two species form colonies of only an adult and a few young. At least one other family (Philodinidae; Bdelloida) contains a species that exhibits a form of coloniality (Philodina megalotrocha). Two hypotheses that attempt to explain the adaptive significance of coloniality (Energetic Advantage and Predatory Avoidance) are reviewed and new information concerning the former is presented. Evolution of coloniality is discussed briefly.  相似文献   
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