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41.
平原人进驻高原后红细胞生成素的变化   总被引:2,自引:0,他引:2  
目的 探讨红细胞生成素在高原低氧适应机制中的作用。方法 对平原进驻海拔 3 70 0m和气 5 3 80m第 7天及半年的健康青年进行血液促红细胞生成素 (EPO)、血红蛋白 (Hb)及血氧饱和度 (SaO2 )检测 ,并与平原健康青年作对照。结果 进驻高原低氧环境EPO、Hb较平原增高显著 (P <0 .0 5或 0 .0 1 ) ,SaO2 降低非常显著 (P <0 .0 1 )。进驻高原第 7天和半年 ,3 70 0m较 5 3 80mEPO ,Hb降低非常显著 ,SaO2 增高非常显著 (P <0 .0 1 )。进驻 3 70 0m ,第 7天较半年EPO无统计学意义 (P >0 .0 5 ) ,Hb ,SaO2 差异显著 (P <0 .0 5或 0 .0 1 ) ;进驻 5 3 80m ,第 7天较半年EPO ,Hb,SaO2 均有显著性差异 (P <0 .0 5或P <0 .0 1 )。结论 在高原缺氧环境下 ,红细胞生成素调节机制紊乱 ,是导致继发性红细胞增多的一个重要环节。  相似文献   
42.
This study was designed to determine the regional and temporal profile of 45calcium (45Ca2+) accumulation following mild lateral fluid percussion (LFP) injury and how this profile differs when traumatic brain injury occurs early in life. Thirty-six postnatal day (P) 17, thirty-four P28, and 17 adult rats were subjected to a mild (approximately 2.75 atm) LFP or sham injury and processed for 45Ca2+ autoradiography immediately, 6 h, and 1, 2, 4, 7, and 14 days after injury. Optical densities were measured bilaterally within 16 regions of interest. 45Ca2+ accumulation was evident diffusely within the ipsilateral cerebral cortex immediately after injury (18-64% increase) in all ages, returning to sham levels by 2-4 days in P17s, 1 day in P28s, and 4 days in adults. While P17s showed no further 45Ca2+ accumulation, P28 and adult rats showed an additional delayed, focal accumulation in the ipsilateral thalamus beginning 2-4 days postinjury (12-49% increase) and progressing out to 14 days (26-64% increase). Histological analysis of cresyl violet-stained, fresh frozen tissue indicated little evidence of neuronal loss acutely (in all ages), but considerable delayed cell death in the ipsilateral thalamus of the P28 and adult animals. These data suggest that two temporal patterns of 45Ca2+ accumulation exist following LFP: acute, diffuse calcium flux associated with the injury-induced ionic cascade and blood brain barrier breakdown and delayed, focal calcium accumulation associated with secondary cell death. The age-dependency of posttraumatic 45Ca2+ accumulation may be attributed to differential biomechanical consequences of the LFP injury and/or the presence or lack of secondary cell death.  相似文献   
43.
PURPOSE: It has recently been suggested that the diagnostic threshold for the prostate specific antigen (PSA) assay be lowered to enhance prostate cancer detection. A 22% incidence of prostate cancer has been reported in men with PSA between 2.5 and 4.0 ng/ml. We designed a study to confirm this observation. MATERIALS AND METHODS: Men who participated in our free early detection program and who had serum PSA between 2.5 and 4.0 ng/ml were asked to undergo prostate biopsy. Of 268 eligible men 151 (56%) agreed to participate in this free trial. All men underwent biopsy using an 11-core multisite directed biopsy scheme. All biopsy cores were color coded for location specificity and examined by 1 pathologist. RESULTS: Cancer was identified in 24.5% (37 of 151) of the men biopsied. The median age of men with cancer was 62 years (range 43 to 74). Conventional systematic sextant biopsies, which accounted for 6 of the 11 cores, detected 73.0% (27 of 37) of the cancers and the alternate site biopsies identified the remaining 10. Gleason score was 6 in 25 men, 3 + 4 in 5, 4 + 3 in 4 and 8 or greater in 3 (median Gleason score 6). There were 14 men who had 1 core positive for cancer, 9 had 2 and 14 had more than 2 (median number of positive cores 2). Of the 14 men with 1 positive core 11 had a less than 3 mm focus of cancer and 8 had only a positive alternate site biopsy. There were 11 cases of abnormal results on digital rectal examination, 5 of which were cancer, and 31 cases of abnormal results on ultrasonography, 13 of which were cancer. Median biological variability in PSA was +/-15% (range 0.4% to 440.0%). CONCLUSIONS: We found a significant incidence of cancer (24.5%, 37 of 51) in men with serum PSA between 2.5 and 4.0 ng/ml. In our study 67.6% of the detected cancers were significant based on the biopsy data. If the PSA threshold is lowered the conventional systematic sextant technique may be preferable to an extended strategy.  相似文献   
44.
目的探讨下腔静脉滤器(ICVF)置入与下肢深静脉血栓形成(DVT)治疗后复发的关系。方法回顾性分析2002年1月至2009年3月我院的确诊为DVT且符合入选标准的261例患者的临床资料。按照随访结果将患者分为复发组和未复发组,分别对可能引起复发的相关因素,如年龄、性别、分型、是否放置ICVF等11项因素进行对比分析。结果多因素logistic回归法分析放置ICVF,未完成抗凝治疗,分型及未行压力循环袜治疗是下肢DVT治疗后复发的独立危险因素(P0.05),而其他7项因素与DVT复发无统计学意义(P0.05)。结论 ICVF置入是DVT治疗后复发的重要危险因素,使用压力循环袜治疗和规范的抗凝治疗对预防DVT治疗后复发有重要的临床意义。  相似文献   
45.
Background: To support safe and effective use of propofol in nonventilated children after major surgery, a model for propofol pharmacokinetics and pharmacodynamics is described.

Methods: After craniofacial surgery, 22 of the 44 evaluated infants (aged 3-17 months) in the pediatric intensive care unit received propofol (2-4 mg [middle dot] kg-1 [middle dot] h-1) during a median of 12.5 h, based on the COMFORT-Behavior score. COMFORT-Behavior scores and Bispectral Index values were recorded simultaneously. Population pharmacokinetic and pharmacodynamic modeling was performed using NONMEM V (GloboMax LLC, Hanover, MD).

Results: In the two-compartment model, body weight (median, 8.9 kg) was a significant covariate. Typical values were Cl = 0.70 [middle dot] (BW/8.9)0.61 l/min, Vc = 18.8 l, Q = 0.35 l/min, and Vss = 146 l. In infants who received no sedative, depth of sedation was a function of baseline, postanesthesia effect (Emax model), and circadian night rhythm. In agitated infants, depth of sedation was best described by baseline, postanesthesia effect, and propofol effect (Emax model). The propofol concentration at half maximum effect was 1.76 mg/l (coefficient of variation = 47%) for the COMFORT-Behavior scale and 3.71 mg/l (coefficient of variation = 145%) for the Bispectral Index.  相似文献   

46.
OBJECTIVE: To report the mid term results of a prospective cohort of iliac artery aneurysms (IAAs) treated with endovascular tubular stent-grafts. METHODS: All IAAs referred to the University Medical Center Groningen between June 1998 and June 2005 were evaluated for endovascular repair. Criteria for repair were a diameter of > or = 30 mm for anastomotic aneurysms and > or = 35 mm for true aneurysms. Preferentially, tubular grafts were used. Follow-up included both radiographs of the abdomen and duplex examination. RESULTS: In 35 patients, 40 IAAs were treated endovascularly with a tubular stent-graft. Elective repair was performed in 30 patients (86%) and emergent repair in five patients (14%). Aneurysms were false in 26 cases (65%) and true in 14 cases (35%). Local anesthesia was used in 74% of the cases. The stent-grafts that were used included the Excluder contralateral limb (n = 28, 70%), Passager (n = 9, 22.5%), Hemobahn (n = 2, 5%), and Wallgraft (n = 1, 2.5%). The mean operation time was 83 +/- 28 minutes (range, 50 to 150 minutes). Mean hospital stay was 3.3 +/- 2.3 days (range, 1 to 12 days). There was no 30-day mortality. Patients were followed up for a mean of 31.2 +/- 20.7 months (range, 3 to 83 months). Complications occurred in two patients during follow-up, including migration with a proximal type I endoleak in one, and occlusion of the stent-graft in the other. The internal iliac artery was intentionally sacrificed in 28 patients (70%), and this led to gluteal claudication in three patients. CONCLUSION: Endovascular repair of iliac artery aneurysms with flexible stent-grafts is a minimally invasive technique and is associated with low mortality and morbidity. Follow-up results up to 5 years suggest that the technique is durable. It should be regarded as a first choice treatment option for suitable aneurysms.  相似文献   
47.
大鼠注射重组腺病毒Ad-HGF后血清中抗腺病毒抗体的检测   总被引:2,自引:0,他引:2  
目的观察大鼠重复给与携带肝细胞生长因子基因的重组腺病毒(recombinant adenovirus carrying hepatocyte growth factor gene,Ad-HGF)后,血清中抗腺病毒抗体的出现时间及消失规律。方法大鼠给与不同剂量的Ad-HGF共14次,利用病毒中和反应(细胞病变效应及绿色荧光方法)观察血清中抗腺病毒抗体。结果手术及正常对照组和实验组动物给药7次前血清处理的细胞均出现明显细胞病变效应及强荧光。之后各剂量组动物血清均对腺病毒有不同程度的中和作用,停药后13周到14周抗体水平很低或已不存在。同时观察到动物性别及给药剂量大小无差异。结论大鼠肌注Ad-HGF7次后,动物血清中可检测到抗腺病毒抗体,停药后13周或14周抗体基本消失,此结果对Ad-HGF的实际应用具有指导意义。  相似文献   
48.
早期帕金森病99Tcm-TRODAT-1多巴胺转运蛋白SPECT脑显像   总被引:5,自引:0,他引:5       下载免费PDF全文
目的 应用99Tcm TRODAT 1进行多巴胺转运蛋白 (DAT)SPECT脑显像 ,探讨其在早期诊断帕金森病中的应用价值。方法 对Hoehn Yahr分级为Ⅰ级的 7例偏侧帕金森病患者和 7例年龄匹配的健康志愿者进行99Tcm TRODAT 1SPECT脑显像。应用计算机感兴趣区 (ROI)技术半定量计算纹状体 /小脑、尾核 /小脑和壳核 /小脑放射性计数比值 ,分别代表纹状体、尾核和壳核的DAT功能水平 ,对帕金森病患者纹状体及其组成部分的DAT功能与健康志愿者的相应区域DAT功能进行比较 ,并对帕金森病患者患侧肢体对侧和同侧纹状体、尾核和壳核的DAT功能分别进行比较。结果 早期帕金森病患者双侧纹状体DAT功能均低于健康志愿者 (1.5 5± 0 .16,1.46± 0 .14 ,1.80± 0 .0 4,P <0 .0 5 ,P <0 .0 1) ,并以患侧肢体对侧纹状体功能降低明显 (P <0 .0 1) ;与健康志愿者相比 ,双侧尾核DAT功能降低 (2 .2 0± 0 .0 5 ,1.88± 0 .3 8,1.62± 0 .2 2 ,P <0 .0 5 ,P <0 .0 0 1) ;与健康志愿者相比 ,双侧壳核DAT功能降低 (1.92± 0 .10 ,1.61± 0 .15 ,1.43± 0 .2 0 ,P <0 .0 1,P <0 .0 0 1) ,且以患侧肢体对侧壳核DAT功能降低明显 (P <0 .0 5 )。所有受检者在显像过程中及显像后均无不良反应发生。结论 99Tcm TRODAT 1SPECT脑显像有助于临床早期诊  相似文献   
49.
鹰嘴豆豆芽降血糖功效成分纯化研究   总被引:1,自引:0,他引:1  
目的研究分离纯化鹰嘴豆豆芽降血糖功效成分的工艺。方法采用聚酰胺-大孔树脂联用技术,考察了HPD100、HPD300、HPD450、HPD600、D101、D141、SA-3、FL-3等8种大孔树脂对鹰嘴豆豆芽降糖活性成分纯化的研究。结果聚酰胺与FL-3大孔树脂联用富集鹰嘴豆豆芽降糖活性成分效果最好,药材与聚酰胺比为5∶1,药材与大孔树脂比为3∶1,树脂径高比为1∶6,以4倍体积的40%乙醇洗除杂,再以70%乙醇洗脱,收集5倍体积洗脱液。富集物降糖活性成分纯度可达52%。结论聚酰胺与FL-3大孔树脂联用富集鹰嘴豆豆芽降血糖功效成分效果最佳,是理想的分离纯化介质。  相似文献   
50.
目的:从抗炎、镇痛、抗凝、活血化瘀4个方面进行前列爽颗粒治疗慢性前列腺炎的药效学研究,为其临床应用提供依据.方法:实验分模型组、前列回春胶囊组、前列爽颗粒1.13,2.25,4.50 g·kg-1组,采用二甲苯致小鼠耳廓肿胀法、醋酸致小鼠腹腔毛细血管通透性增高法、角叉菜胶致大鼠足跖肿胀法、小鼠醋酸扭体法建模,小鼠以剪尾法测定出血时间(BT),玻片法测定凝血时间(CT),ELISA法测凝血酶原时间(PT),BM-15A型显微镜观察小鼠耳廓毛细血管口径和毛细血管网交点数,来评价前列爽颗粒的抗炎、镇痛、抗凝、活血化瘀作用.结果:前列爽颗粒1.13,2.25,4.50 g·kg-1组能明显抑制二甲苯所致的小鼠耳廓肿胀(P<0.01),2.25,4.50 g·kg-1组降低醋酸致小鼠毛细血管通透性(P<0.01),0.79,1.58,3.15 g·kg-1组能抑制角叉菜胶所致的大鼠足跖肿胀(P<0.01),显著减少醋酸所致的小鼠扭体反应(P<0.01),2.25,4.50 g·kg-1组能延长PT,BT,CT(P <0.01),毛细血管口径和毛细血管网交点数明显增加(P<0.01).结论:前列爽颗粒具有抗炎、镇痛、抗凝、活血化瘀的作用.  相似文献   
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