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41.
42.
GJ Levy ; G Selset ; D McQuiston ; SJ Nance ; G Garratty ; LE Smith ; D Goldfinger 《Transfusion》1988,28(3):265-267
Several published reports have documented the variable survival of Yt(a+) red cells (RBC) in patients with anti-Yt(a) as measured by 51Chromium (Cr)-labeled RBC survival studies. Similar studies with anti-Yt(b) have not been reported. A 51Cr-labeled RBC survival study was performed using Yt(b+) RBCs and a monocyte monolayer assay in a young hemodialysis patient who required chronic transfusion therapy and who had developed anti-Yt(b). The survival of the transfused RBCs was 100 and 93 percent at 1 and 24 hours, respectively, with a half life of 21 days at termination of the study (normal, 28 to 32 days). These results showed no evidence of rapid destruction of the Yt(b+) RBCs, indicating that this patient could be transfused safely with blood from Yt(b+) donors. Long-term survival of the 51Cr-labeled Yt(b+) RBCs was shortened moderately, however, a finding that correlated with a slightly abnormal monocyte monolayer assay test. 相似文献
43.
两种麻醉方法对单双肺通气期间能量代谢和呼吸氧价及应激反应的影响 总被引:1,自引:0,他引:1
目的:观察胸段硬膜外复合全静脉麻醉和全静脉麻醉对单、双肺通气能量代谢、呼吸氧价和应激反应的影响,比较两者的差异。方法:选择2004-07/2005-01徐州医学院附属医院心胸外科择期行食管癌根治术且需要单肺通气的患者40例,按随机数字表法分为硬膜外复合全静脉麻醉组(n=20)和全静脉麻醉组(n=20),经患者同意并签字后进入试验。分别在单肺通气和双肺通气时进行氧耗量、二氧化碳排出量、能量代谢和呼吸商测定,同时测量肾上腺素、去甲肾上腺素、皮质醇和血糖水平。结果:40例患者全部进入结果分析,无脱落。①在单、双肺通气时硬膜外复合全静脉麻醉组的氧耗量、二氧化碳排出量、能量代谢均高于全静脉麻醉组(P<0.05);两组患者单肺通气时段氧耗量、二氧化碳排出量、能量代谢低于双肺通气时段,但差异无显著性意义(P>0.05)。②在单、双肺通气时硬膜外复合全静脉麻醉组的肾上腺素、去甲肾上腺素、皮质醇和血糖水平均低于全静脉麻醉组(P<0.05);单、双肺通气相比,两组患者肾上腺素、去甲肾上腺素变化差异无显著性意义(P>0.05)。结论:与全静脉麻醉相比,胸段硬膜外阻滞复合全静脉麻醉能够增加胸科手术的氧耗量、能量代谢,减轻应激反应。单、双肺通气期间没有明显差异。 相似文献
44.
目的:采用定量分析方法比较体育与非体育专业大学生静态平衡能力,分析运动及性别对大学生静态平衡功能的影响。方法:于2007-01/03选取首都体育学院在校大学生共78名为受试对象,其中体育(武术)专业学生40名,非体育(康复)专业学生38名。所有选取对象了解试验目的,并同意参与本实验。采用意大利PosturalEqua平静分析系统,对实验对象分别在睁眼60s、闭眼60s两种状态下测试其静态平衡的各项指标,包括压力中心,线形图总长度,最大摆幅,线形图面积,LFS指数,压力分布,稳定性图及隆伯格值。结果:78名为受试对象均进入结果分析。①两专业学生压力中心X轴短于Y轴、压力分布前(%)高于后(%)(P<0.01)。②在闭眼状态下,体育专业男大学生在指标LFS指数和额状面上大于非体育专业(P<0.05)。③非体育业大学生在睁眼状态下,Y值女性小于男性,额状面值女性大于男性。男、女生睁闭眼差值进行比较时,女性在线形图总长度、额状面和LFT指数均大于男性(P<0.01),而线形图面积小于男性(P<0.05)。④体育专业大学生在睁眼状态下,指标参数Y值女性小于男性,额状面值女性大于男性;闭眼状态下,指标参数Y值女性小于男性,额状面值和LFS值女性大于男性。男、女生睁闭眼差值比较,女性在线形图总长度、额状面和LFT指数均大于男性(P<0.05,P<0.01),而线形图面积小于男性(P<0.05)。结论:①运动训练对大学生静态平衡影响不大,但对男性大学生的某些平衡指标却有显著影响。②性别对大学生的静态平衡均产生影响,表现为男性平衡的微控制能力优于女性。 相似文献
45.
Donor screening for antibody to hepatitis B core antigen and hepatitis B virus infection in transfusion recipients 总被引:10,自引:0,他引:10
JW Mosley ; CE Stevens ; RD Aach ; FB Hollinger ; LT Mimms ; LR Solomon ; LH Barbosa ; GJ Nemo 《Transfusion》1995,35(1):5-12
BACKGROUND: Testing for antibody to hepatitis B core antigen (anti-HBc) as a surrogate for hepatitis C viremia is no longer needed for blood donor screening. Currently, the important question is how much its use supplements hepatitis B surface antigen (HBsAg) donor screening in preventing transfusion-transmitted hepatitis B virus (HBV) infection. STUDY DESIGN AND METHODS: In a study conducted in the 1970s, 64 blood donors were associated with 15 cases of HBV (1.0%) in 1533 transfusion recipients. Sera from 61 donors at donation and 29 follow-up visits were available for present-day assays for HBsAg, HBV DNA, anti-HBc, and antibody to HBsAg (anti-HBs). RESULTS: HBsAg was found in four previously negative blood donors; HBV DNA was limited to three of these four. Anti-HBc was detected in six HBsAg-negative donors. Two other donors were negative in all assays at donation, but positive for anti- HBc and anti-HBs 2 to 4 months later. The remaining donors were negative for all HBV markers, which left five recipient cases unexplained. No HBV transmission was observed when anti-HBs sample-to- negative control values were > or = 10. CONCLUSION: Some 33 to 50 percent of cases of hepatitis B that could be transmitted by transfusion of blood from HBsAg-negative donors are prevented by anti- HBc screening. Anti-HBc-positive donors unequivocally positive for anti- HBs should be considered noninfectious for HBV and should be allowed to donate. Anti-HBc screening of paid plasmapheresis donors, supplemented by anti-HBs testing, would reduce the amount of HBV to be processed by virus inactivation and increase the content of anti-HBs in plasma pools. 相似文献
46.
目的:探索膝关节前交叉韧带重建术的各个关键技术环节,为提高前交叉韧带修复的临床效果提供理论和实践依据。方法:通过分析与总结与前交叉韧带重建相关的文献资料,包括其手术方式、移植物的选择、骨道定位、髁间窝成形、移植物预张与张力、移植物固定等,同时结合作者的工作经验旨在进一步提高前交叉韧带重建技术。结果:①手术方式选择:膝关节镜下生物材料移植重建前交叉韧带取得比以往优良的临床效果,已得到广泛认可。多数采用单束重建,部分学者正在尝试双束重建以改善移植物生物力学性能。②移植材料的选择:包括自体和同种异体材料,其中自体骨-髌腱-骨与腘绳肌腱最为常用。骨-髌腱-骨由于两端带有骨块,固定牢靠,允许早期重返运动场,颇受年轻运动员青睐。腘绳肌腱取材切口小,术后很少出现膝前痛,但其稳定性不如骨-髌腱-骨,且术后相对容易出现骨隧道扩大。异体移植物在体内结合、重塑速度较自体移植慢,但若经过严格的供体筛选、合理的组织取材、消毒和保存,而不减弱移植物强度,仍可取得与自体移植相当的效果。③骨道位置:正确的骨道定位非常重要,骨道位置太靠前会造成髁间窝撞击和伸直受限。研究表明,术中采用骨性标志定位法要比采用软组织标志定位法准确,术中摄片有助于骨道位置的正确定位。④髁间窝成形术:髁间窝成形的目的是为了便于更清楚的观察髁间窝后侧,同时也是为了避免髁间窝撞击综合征的发生,由于髁间窝过度成形会增加关节出血、疼痛、肿胀以及骨赘生长,所以一般不主张广泛的髁间窝成形,除非术中确有必要时才进行。⑤移植物预张与张力:移植物初始张力不够会导致膝关节持续松弛,而张力过高会限制关节活动并加速关节退变。目前对于最佳的初始张力尚无确切说法。⑥固定:现在已经研制出许多不同类型的固定材料。对于骨-髌腱-骨而言,界面挤压螺钉单切口重建前交叉韧带时,股骨侧靠近关节腔侧固定,胫骨侧远离关节腔侧固定,双切口技术时胫骨侧靠近关节腔侧固定,股骨侧远离关节腔侧固定。股骨侧固定完毕后,膝关节取何角度对胫骨侧进行固定尚存争议。膝关节稍屈曲状态下固定不容易发生松弛,但正常的膝关节在前后方向上是允许有一定松弛度的。有些学者认为在膝关节完全伸直状态下固定可以避免屈曲挛缩畸形的发生并允许前后方向有轻度松弛。而有些学者认为在膝关节稍微屈曲状态下固定会更紧。结论:要真正做到解剖、生物力学、生理功能全方位重建,前交叉韧带重建技术,仍需不断完善,分子生物学、基因工程和组织工程技术的发展以及计算机辅助机器人手术的开展会使前交叉韧带重建技术日臻完善。 相似文献
47.
目的:建立血虚和免疫抑制动物模型,观察鸡胚胎低温提取物对其红细胞造血以及免疫器官质量的影响。方法:实验于2001-04/2002-09在新乡医学院药物研究室完成。①实验材料:健康昆明种小鼠50只,雌雄各半。鸡胚胎素[中国发明专利公开(公告)号:CN1748713],符合研究者申报专利时提出的质量检验标准。②鸡胚胎素对血虚模型小鼠红细胞数值及血红蛋白含量的影响:取20只小鼠,随机排列表法分为鸡胚胎素组、模型对照组,10只/组,建立失血性血虚动物模型。失血后24h当红细胞数<3.2×1012L-1、血红蛋白含量<84g/L,且小鼠外观出现皮色苍白、食欲不振等现象时,代表造模成功。次日,鸡胚胎素组给予鸡胚胎素5g/(kg·d)灌胃,模型对照组给予生理盐水20mL/(kg·d)灌胃,连续14d。分别于失血前、失血后24h、末次给鸡胚胎素后2h尾部采血测定两组红细胞数量及血红蛋白含量的变化。③鸡胚胎素对免疫抑制模型小鼠免疫器官质量的影响:取30只小鼠,随机排列表法分为鸡胚胎素组、模型对照组、正常对照组,10只/组。鸡胚胎素组给予鸡胚胎素5g/(kg·d)灌胃,模型对照组和正常对照组均灌服等量生理盐水,连续14d。在第11天上午鸡胚胎素灌胃2h后,鸡胚胎素组、模型对照组腹腔注射环磷酰胺60mg/(kg·d),连续4d,复制免疫抑制动物模型。末次给予环磷酰胺2h后颈椎脱位法处死小鼠,计算胸腺、脾脏质量指数。结果:50只小鼠均进入结果分析。①失血前及失血后24h鸡胚胎素组与模型对照组的红细胞数值、血红蛋白含量基本相似(P>0.05)。末次给鸡胚胎素后2h与模型对照组比较,鸡胚胎素组红细胞数值、血红蛋白含量均明显升高(t=3.39,P<0.01;t=2.52,P<0.05)。②末次给环磷酰胺2h后与模型对照组比较,鸡胚胎素组、正常对照组的胸腺质量指数和脾脏质量指数均明显升高(t=6.62,P<0.01;t=2.47,P<0.05)。结论:鸡胚胎素灌胃对血虚小鼠具有较好的促红细胞造血功能,同时对环磷酰胺造成的免疫器官质量下降具有明显的增重作用。 相似文献
48.
JW Mosley ; W Huang ; DO Stram ; MJ Nowicki ; FB Hollinger ; RD Aach ; CE Stevens ; LH Barbosa ; GJ Nemo 《Transfusion》1996,36(9):776-781
BACKGROUND: Hepatitis virus(es) that are neither hepatitis B (HBV) nor hepatitis C (HCV) (non-B, non-C [NBNC]) may be transmitted by transfusion. The present study assessed donor values for alanine aminotransferase (ALT) and antibody to hepatitis B core antigen (anti- HBc) for their association with HCV and NBNC hepatitis outcomes among allogeneic blood recipients. STUDY DESIGN AND METHODS: Data on blood donors and recipients enrolled in the Transfusion- Transmitted Viruses Study in four United States cities from 1974 through 1980 were supplemented by anti-HBc testing of donors and anti-HCV evaluation of recipients. Two statistical approaches estimated the value of these indirect tests in detecting donors associated with HCV seroconversion and NBNC hepatitis in recipients. RESULTS: For HCV cases, donor ALT alone (at > or = 60 IU/L) had a sensitivity and a specificity of 30 and 96 percent, respectively, and anti-HBc alone (at > or = 60% inhibition) had a sensitivity and specificity of 53 and 86 percent, respectively. The two markers combined had a sensitivity and a specificity of 69 and 83 percent. For NBNC hepatitis cases, each measure had low sensitivity (20%) that was not improved by using both (28%) [corrected]. CONCLUSION: The indirect tests proved to be equal in sensitivity to the first-generation anti-HCV tests. The positive predictive power of these indirect tests in the 1980s was sufficient to affect HCV incidence in studies during that period. Improved anti-HCV assays, however, replaced the need for indirect tests. The sensitivity of indirect tests for NBNC hepatitis contributed little. 相似文献
49.
BACKGROUND:
Diagnosing pulmonary tuberculosis (PTB) is challenging in patients who are unable to spontaneously expectorate. Published evidence suggests that induced sputum (IS) is the least invasive and most cost-effective method of diagnosis, and should be used before fibre-optic bronchoscopy (FOB).METHODS:
The medical records of 337 adults treated for PTB in northern Alberta between 1997 and 2007 were reviewed to determine whether local practice patterns reflect the evidence. Microbiological data were collected from the Provincial Laboratory for Public Health. Demographic information was collected from the patients’ charts.RESULTS:
A total of 8.5% (26 of 307) of PTB patients had IS collected, whereas 35.8% (110 of 307) underwent FOB. Among FOB patients, 56.4% (62 of 110) had no sputum sent before the procedure and 29% (18 of 62) of these patients were smear positive. Only five patients referred for FOB had IS sent previously. There were no demographic factors predictive of IS use, whereas being an inpatient at a teaching facility or having a nodule or mass on chest x-ray was predictive of FOB referral. Because so few IS samples were available, not all patients had spontaneously expectorated sputum, IS and FOB tests performed; thus, the calculated yields were not comparable with one another.CONCLUSIONS:
Despite published evidence recommending IS collection before FOB referral in suspected PTB patients, clinicians in our health region appeared to prefer early FOB over IS by a large margin. This practice pattern is less cost effective and exposes patients and health care workers to greater risk. Further research is needed to identify the reasons for the underuse of sputum induction. 相似文献50.
Aamir Z. Khan Gareth Morris-Stiff Masatoshi Makuuchi 《Journal of Hepato-Biliary-Pancreatic Surgery》2009,16(2):137-144
Background and aims Neoadjuvant chemotherapy is increasingly being used to enlarge the cohort of patients who can be offered hepatic resection
for malignancy. However, the impact of these agents on the liver parenchyma itself, and their effects on clinical outcomes
following hepatic resection remain unclear. This review identifies patterns of regimen-specific chemotherapy-induced hepatic
injury and assesses their impact on outcomes following hepatic resection for colorectal liver metastases (CLM).
Methods An electronic search was performed using the MEDLINE (US Library of Congress) database from 1966 to May 2007 to identify relevant
articles related to chemotherapy-induced hepatic injury and subsequent outcome following hepatic resection.
Results The use of the combination of 5-flourouracil and leucovorin is linked to the development of hepatic steatosis, and translates
into increased postoperative infection rates. A form of non-alcoholic steatohepatitis (NASH) related to chemotherapy and otherwise
known as chemotherapy-associated steatohepatitis (CASH) is closely linked to irinotecan-based therapy and is associated with
inferior outcomes following hepatic surgery mainly due to hepatic insufficiency and poor regeneration. Data on sinusoidal
obstruction syndrome (SOS) following treatment with oxaliplatin are less convincing, but there appears to be an increased
risk for intra-operative bleeding and decreased hepatic reserve associated with the presence of SOS. Intra-arterial floxuridine
therapy damages the extrahepatic biliary tree in addition to causing parenchymal liver damage, and has been shown to be associated
with increased morbidity after hepatic resection.
Conclusion Agent-specific patterns of damage are now being recognized with increasing use of neoadjuvant chemotherapy prior to surgery.
The potential benefits and risks of these should be considered on an individual patient basis prior to hepatic resection. 相似文献