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81.
游泳训练大鼠血浆生物活性肽含量的变化及意义 总被引:5,自引:0,他引:5
目的研究运动性心肌肥大形成中血浆生物活性肽的含量及意义.方法wistar大鼠分为运动训练组和对照组,NPY、CGRP、ET和ANP用放射免疫方法测定,血压和心率用八道生理记录仪记录.结果(1)运动组大鼠游泳训练8周后,心脏系数比对照组增加36.8%(P<0.05),而收缩压、舒张压、平均动脉压和心率与对照组无差异(P>0.05);(2)运动组心肌肥大大鼠血浆NPY均比照组降低88%(P<0.01);(3)运动组心肌肥大大鼠血浆CGRP比对照组升高31%(P<0.01);(4)运动组血浆ET和ANP浓度与对照组无差异.结论运动性心肌肥大形成中血浆的CGRP、NPY含量变化不同,提示CGRP和NPY对运动性心肌肥大的形成可能有重要作用. 相似文献
82.
观察脑梗死(CI)患者神经肽Y(NPY)、神经降压素(NT)、胃动素(MTL)、降钙素基因
相关肽(CGRP)浓度变化及其临床意义。方法选择C162例,用放免法检测血浆NPY、NT、MTL与CGRP浓度。结果NPY、NT与MTL浓度显著高于对照组(P<0.0001);于发病后24h内显著升高,7d内达高峰,8~15d开始下降,15d后仍在较高水平。NPY浓度重型与大灶组显著高于轻型(P<0.05)与小灶组(P<0.01);发病积分≥6分组显著高于<6分组(P<0.05);高血压组显著高于正常血压组(P<0.05)。NT与MTL浓度重型组显著高于中(P<0.05)、轻型组(P<0.01);高血糖组显著高于正常血糖组(P<O.01)。CGRP浓度显著低于对照组(P<0.0001),发病24h内即显著降低,2~7d进一步降低,8~15d开始升高,15d后逐渐升至正常水平。重型与大灶组显著高于轻型(P<0.0001)、中型(P<0.01)与小灶组(P<0.01);伴发病积分≥6分组显著低于<6分组(P<0.05)。结论CI患者NPY、NT、MTL、CGRP浓度变化以7d内最显著,15d后逐渐恢复正常水平;四种浓度监测可作为判断CI患者病情严重程度、病灶大小及伴发病的实验室指标。 相似文献
83.
目的研究降钙素基因相关肽(CGRP)、神经肽Y(NPY)与先心病肺高压的关系,分析两者是否具有相关性.方法采用放射免疫法测定80例先天性心脏病(13例非肺高压,67例肺高压)血清NPY、CGRP的浓度,比较两组间不同采血部位及手术前后水平变化.结果血浆NPY及CGRP浓度非肺高压组与轻、中、重度肺高压组均存在显著性差异;手术前后轻、中度肺高压组存在显著性差异,而重度肺高压组差异不明显;NPY与CGRP存在负相关关系.结论NPY及CGRP在先天性心脏病肺动脉高压的发生机制中有重要的作用,NPY/CGRP比值可作为估测肺动脉压力和判断先心病预后的重要指标. 相似文献
84.
目的 建立准确测定姜黄属4种中药材挥发油中莪术醇含量。方法 以高效毛细管柱序升温气相色谱法测定莪术醇的含量。结果 本法能准确测定莪术醇的含量,回收率为101.4%,RSD为0.4%,还测定了4种姜黄属药物(温郁金、姜黄,桂莪术,蓬莪术)中莪术醇的含量,发现4种药材中莪中醇的含量差异显著。结论 为姜黄属药材质量的分析控制提供可行的含量测定方法。 相似文献
85.
目的:鉴别益母草中是否含阿魏酸,方法:采用薄层色谱法和高效液相色谱法鉴别不同提取溶煤制备的样品,结果:从益母草中能检出阿魏酸。结论:益母草中可能含游离的阿魏酸,以5%Na2CO3溶液替代药典中的甲醇提取,方法简化,稳定性高,重现性好。 相似文献
86.
中国北方汉族、维吾尔族、哈萨克族DYS19基因座的遗传多态性 总被引:4,自引:0,他引:4
目的;研究DYS19基因座在中国北方汉族、维吾尔族、哈萨克族群体中的遗传多态性及其法医学应用。方法:应用聚合酶链反应后变性聚丙烯酰胺凝胶电泳分离扩增产物结合银染显带的方法,对101例北方汉族、56例维吾尔族、30例哈萨克族无关男性个体的DYS19基因座进行检测。结果:DYS19基因座在3个群体中共检出5种等位基因,基因频率分布范围分别为0.069-0.594,0.071-0.500,0.100-0.667;个人识别机率分别为0.600,0.675,0.491。χ^2检验表明等位基因分布具有明显的人群差异。家系调查符合单体父系遗传方式。结论:DYS19基因座个人识别机率高,属较高鉴别能力的遗传标记系统,且具有明显的人群分布差异,在法医学及人类遗传学研究中具有重要的应用价值。 相似文献
87.
Carlos Solano Lourdes Vázquez Estela Giménez Rafael de la Cámara Eliseo Albert Montserrat Rovira Ildefonso Espigado Carmen M. Calvo Javier López-Jiménez María Suárez-Lledó Anabella Chinea Albert Esquirol Ariadna Pérez Aránzazu Bermúdez Raquel Saldaña Inmaculada Heras Ana J. González-Huerta Tamara Torrado Guiomar Bautista Montserrat Batlle Santiago Jiménez Carlos Vallejo Pere Barba María Á. Cuesta José L. Piñana David Navarro 《American journal of transplantation》2021,21(1):258-271
The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research. 相似文献
88.
William A. Werbel Sunjae Bae Sile Yu Fawaz Al Ammary Dorry L. Segev Christine M. Durand 《American journal of transplantation》2021,21(2):717-726
Kidney transplant (KT) outcomes for HIV-infected (HIV+) persons are excellent, yet acute rejection (AR) is common and optimal immunosuppressive regimens remain unclear. Early steroid withdrawal (ESW) is associated with AR in other populations, but its utilization and impact are unknown in HIV+ KT. Using SRTR, we identified 1225 HIV+ KT recipients between January 1, 2000, and December 31, 2017, without AR, graft failure, or mortality during KT admission, and compared those with ESW with those with steroid continuation (SC). We quantified associations between ESW and AR using multivariable logistic regression and interval-censored survival analysis, as well as with graft failure and mortality using Cox regression, adjusting for donor, recipient, and immunologic factors. ESW utilization was 20.4%, with more zero HLA mismatch (8% vs 4%), living donors (26% vs 20%), and lymphodepleting induction (64% vs 46%) compared to the SC group. ESW utilization varied widely across 129 centers, with less use at high- versus moderate-volume centers (6% vs 21%, P < .001). AR was more common with ESW by 1 year (18.4% vs 12.3%; aOR: 1.081.612.41, P = .04) and over the study period (aHR: 1.021.391.90, P = .03), without difference in death-censored graft failure (aHR 0.600.911.36, P = .33) or mortality (aHR: 0.751.151.77, P = .45). To reduce AR after HIV+ KT, tailoring of ESW utilization is reasonable. 相似文献
89.
Cathy Logan Ily Yumul Javier Cepeda Victor Pretorius Eric Adler Saima Aslam Natasha K. Martin 《American journal of transplantation》2021,21(2):657-668
Outcomes following hepatitis C virus (HCV)-viremic heart transplantation into HCV-negative recipients with HCV treatment are good. We assessed cost-effectiveness between cohorts of transplant recipients willing and unwilling to receive HCV-viremic hearts. Markov model simulated long-term outcomes among HCV-negative patients on the transplant waitlist. We compared costs (2018 USD) and health outcomes (quality-adjusted life-years, QALYs) between cohorts willing to accept any heart and those willing to accept only HCV-negative hearts. We assumed 4.9% HCV-viremic donor prevalence. Patients receiving HCV-viremic hearts were treated, assuming $39 600/treatment with 95% cure. Incremental cost-effectiveness ratios (ICERs) were compared to a $100 000/QALY gained willingness-to-pay threshold. Sensitivity analyses included stratification by blood type or region and potential negative consequences of receipt of HCV-viremic hearts. Compared to accepting only HCV-negative hearts, accepting any heart gained 0.14 life-years and 0.11 QALYs, while increasing costs by $9418/patient. Accepting any heart was cost effective (ICER $85 602/QALY gained). Results were robust to all transplant regions and blood types, except type AB. Accepting any heart remained cost effective provided posttransplant mortality and costs among those receiving HCV-viremic hearts were not >7% higher compared to HCV-negative hearts. Willingness to accept HCV-viremic hearts for transplantation into HCV-negative recipients is cost effective and improves clinical outcomes. 相似文献
90.
Jignesh K. Patel Guillaume Coutance Alexandre Loupy Deanna Dilibero Michele Hamilton Michelle Kittleson Evan Kransdorf Babak Azarbal Osamu Seguchi Xiaohai Zhang David Chang Dael Geft Lawrence Czer Shaida Varnous Jon A. Kobashigawa 《American journal of transplantation》2021,21(7):2479-2488
Allosensitization represents a major barrier to heart transplantation (HTx). We assessed the efficacy and safety of complement inhibition at transplant in highly sensitized heart transplant recipients. We performed a single-center, single-arm, open-label trial (NCT02013037). Patients with panel reactive antibodies (PRA) ≥70% and pre–formed donor-specific antibodies (DSA) were eligible. In addition to standard of care, patients received nine infusions of eculizumab during the first 2 months posttransplant. The primary composite endpoint was antibody-mediated rejection (AMR) ≥pAMR2 and/or left ventricular dysfunction during the first year. Secondary endpoints included hemodynamic compromise, allograft rejection, and patient survival. Twenty patients were included. Median cPRA and mean fluorescence intensity of immunodominant DSA were 95% (90%–97%) and 6250 (5000–10 000), respectively. Retrospective B cell and T cell flow crossmatches were positive in 14 and 11 patients, respectively. The primary endpoint occurred in four patients (20%). Survival at 1 year was 90% with no deaths resulting from AMR. In a prespecified analysis comparing treated patients to matched control patients, we observed a dramatic reduction in the risk of biopsy-proven AMR in patients treated with eculizumab (HR = 0.36, 95% CI = 0.14–0.95, p = .032). Our findings support the prophylactic use of complement inhibition for heart transplantation at high immunological risk. ClinincalTrials.gov, NCT02013037. 相似文献