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991.
目的探讨成年家兔延髓孤束核(NTS)神经元上N-甲基-D-天冬氨酸(NMDA)受体和非NMDA受体在急性缺氧引起的外周化学感受器兴奋性传导中的作用。方法通过显微注射技术向家兔NTS内注射NMDA受体拮抗剂2-氨基-5-磷酸戊酸(AP-5)和(或)非NMDA受体拮抗剂6.7-二硝基喹诺林-2.3-二酮(DNQX),观察其对急性缺氧时膈神经放电变化的影响。结果应用AP-5或DNQX对缺氧引起的呼吸增强均产生了抑制效应,两种受体拮抗剂之间有交互作用。结论哺乳动物NTS神经元上的NMDA受体和非NMDA受体在介导急性缺氧时外周化学感受性信号向中枢的传递中均发挥作用,NMDA受体尤为重要。两种受体有协同性作用。 相似文献
992.
p16INK4A and p15INK4B gene deletions in primary leukemias 总被引:4,自引:0,他引:4
Haidar MA; Cao XB; Manshouri T; Chan LL; Glassman A; Kantarjian HM; Keating MJ; Beran MS; Albitar M 《Blood》1995,86(1):311-315
The 9p21 locus has been deleted at a high frequency in a wide variety of tumors. Recently, two genes, p16INK4A and p15INK4B (also called MTS1 and MTS2), have been localized in close proximity at the 9p21 locus, encoding cyclin-dependent kinases 4/6 inhibitors of relative molecular mass 16 kD and 15 kD, respectively and also found to be deleted at a high frequency in tumor cell lines. We analyzed p16INK4A and p15INK4B genes in 178 cases of primary leukemias including 81 cases of chronic lymphocytic leukemia (CLL), seven of hairy cell leukemia (HCL), seven of chronic myelogenous leukemia (CML), 43 of acute myelogenous leukemia (AML), 27 of acute lymphoblastic leukemia (ALL), and 13 of myelodysplastic syndrome (MDS) by Southern blot analyses. The ALL cases showed a relatively high frequency of homozygous deletions (22%, 6 of 27) at the p16INK4A gene locus. Interestingly, of the six cases with p16INK4A homozygous deletions, only three showed homozygous deletions at the p15INK4B gene. In 81 CLL patients, we detected one homozygous and five heterozygous deletions at both the p16INK4A and p15INK4B genes and two heterozygous deletions at the p16INK4A gene alone. Deletion of these two genes in AML cases is relatively low (9%). We did not detect deletions in any of the MDS, HCL, and CML cases examined. Sequence analyses of p16INK4A gene of six CLL cases with heterozygous deletion at this locus showed a 27-bp deletion at the splice acceptor site of intron 1 in one case and changes in the coding sequence in three other cases. The data presented in this report showed that (1) p16INK4A and p15INK4B genes are preferentially deleted homozygously in ALL and heterozygously in CLL cases with frequent mutation in the second allele, and (2) p16INK4A gene appears to be more frequently deleted than p15INK4B gene. 相似文献
993.
目的:探讨射频导管消融在治疗“快—慢”型室上性心律失常中的作用。方法:用射频导管消融的方法治疗了4例“快—慢”型室上性心律失常病人。结果:1991年1月至1996年1月间,对241例次各种快速性心律失常进行了射频导管消融治疗。其中4例为“快—慢”型室上性心律失常,2例为反复发作性房室结折返性心动过速(AVNRT),终止时有长时间的心脏停搏并引起晕厥,原准备安装永久性心脏起搏器,AVNRT根治后,由其引起的症状不复存在,电生理检查窦房结功能正常,故未安装起搏器;另2例均已植入永久性心脏起搏器,1例频繁发作快速心室率心房颤动并经常引起急性心功能不全,1例反复发作AVNRT、心房扑动和心房颤动且有明显的症状,射频导管消融治疗后症状均消失,射频导管消融术对起搏器的功能无影响。3例平均随访31±2个月,1例随访2个月未见并发症和临床症状复发。结论:射频导管消融法治疗“快—慢”型室上性心律失常具有重要的临床价值。 相似文献
994.
脑型并殖吸虫病是颅内感染卫氏并殖吸虫或斯氏并殖吸虫引起的疾病 ,其对中枢神经系统损伤较大 ,早期诊断具有重要的临床意义。为探讨其早期影像学特点 ,作者回顾分析了 8例患者的CT和磁共振 (MRI)资料 ,报告如下。1 研究对象及方法8例患者中男 5例 ,女 3例 ,年龄 6~ 13岁 ,居住陕西省 (5例 )及河南省 (3例 )。 5例有食石蟹史。 2例经手术病理检查确诊 ,6例皮内试验及ELISA阳性。 3例有皮下游走性结节。 2例脑脊液嗜酸粒细胞增高。肺部均无症状和体征。主要表现为头痛、呕吐、癫痫发作、肢体无力或偏瘫。 8例经吡喹酮治疗后症状有不同… 相似文献
995.
996.
Jia‐Li Wang Kai‐Xin Wang Tian‐Lei Han Jin‐Mei Li Xu He Rui‐Xue Rong Zhi‐Ran Cao Xiao‐Liu Li Ke‐Rang Wang 《Chemical biology & drug design》2020,96(2):870-877
Camptothecin (CPT) and its analogues show potent antitumour activity. However, poor water solubility and severe side effects have restricted their applications in clinical practice. In this paper, a novel self‐assembly based on camptothecin and carbamoylmannose conjugates ( CPT‐Man ) was constructed. The self‐assembly increased the water solubility of camptothecin to 0.64 mg/ml and antitumour activity. Moreover, CPT‐Man could induce obvious cancer cell apoptosis. This work provides a new approach for exploring carbohydrate‐modified antitumour properties by self‐assembled CPT drugs. 相似文献
997.
[摘要]目的:对比高浓度氧疗与滴定氧疗对儿童哮喘急性发作患儿经皮二氧化碳分压(PtCO2)的影响。方法:选取因中度或重度哮喘发作就诊于我院的100例2~18岁哮喘病患儿为研究对象,随机分为高浓度氧疗组(HCOT组)或滴定氧疗组(TOT组),在0、20、40、60、90 min时测量PtCO2、哮喘评分,并对两组患儿住院率进行对比分析。结果:60 min时,HCOT组患儿PtCO2升高>4 mm Hg和PtCO2升高>6 mm Hg比例高于TOT组,HCOT组患儿PtCO2升高>4 mm Hg且PtCO2>38 mm Hg比例高于TOT组(P<0.05)。HCOT组PtCO2平均升高速率均高于TOT组,哮喘评分高于TOT组,90 min时HCOT组呼气高峰流量(PEFR)高于TOT组(P<0.05)。HCOT组住院率44.0%(22/50),高于TOT组的30.0%(15/50),但差异无统计学意义(P>0.05)。结论:儿童哮喘急性发作期高浓度氧疗可导致PtCO2水平明显升高,哮喘评分升高,入院率呈上升趋势。治疗儿童哮喘急性发作时,并不需要为所有患儿提供高浓度氧气治疗,采用滴定氧疗使血氧饱和度维持在92%以上,能同时避免低氧血症和高碳酸血症的发生。 相似文献
998.
严重急性呼吸综合征冠状病毒2(SARS-CoV-2)感染的疫情已经持续了近2个月,现处于疫情胶着的状态。因儿童SARSCoV-2感染症状不典型,慢性肾脏疾病(CKD)患儿是高危感染人群,儿童肾脏专科病房的管理在复工、返校压力下,面临疫情防控的新挑战,国家临床研究中心肾脏病房、重庆市医学会儿科专委会肾脏学组,为进一步做好肾脏专科病房的疫情防控工作,结合目前疫情和相关防控建议,推荐SARS-CoV-2疫情期间儿童肾脏病房感染防控思维导图,以供儿童肾脏专科病房参考。 相似文献
999.
Yanming Liu Yue Cao Xijun Liu Liangyin Wu Wencan Cai 《Journal of clinical laboratory analysis》2021,35(1):e23581
Background(a) To evaluate the clinical performance of endocrine analytes using the sigma metrics (σ) model. (b) To redesign quality control strategies for performance improvement.MethodsThe sigma values of the analytes were initially evaluated based on the allowable total error (TEa), bias, and coefficient of variation (CV) at QC materials level 1 and 2 in March 2018. And then, the normalized QC performance decision charts, personalized QC rules, quality goal index (QGI) analysis, and root causes analysis (RCA) were performed based on the sigma values of the analytes. Finally, the sigma values were re‐evaluated in September 2018 after a series of targeted corrective actions.ResultsBased on the initial sigma values, two analytes (FT3 and TSH) with σ > 6, only needed one QC rule (13S) with N2 and R500 for QC management. On the other hand, seven analytes (FT4, TT4, CROT, E2, PRL, TESTO, and INS) with σ < 4 at one QC material level or both needed multiple rules (13S/22S/R4S/41S/10X) with N6 and R10‐500 depending on different sigma values for QC management. Subsequently, detailed and comprehensive RCA and timely corrective actions were performed on all the analytes base on the QGI analysis. Compared with the initial sigma values, the re‐evaluated sigma metrics of all the analytes increased significantly.ConclusionsIt was demonstrated that the combination of sigma metrics, QGI analysis, and RCA provided a useful evaluation system for the analytical performance of endocrine analytes. 相似文献
1000.
Junfeng Zhang Jiajia Cao Hui Xu Guanping Dong Ke Huang Wei Wu Jingjing Ye Junfen Fu 《Journal of clinical laboratory analysis》2021,35(2)
BackgroundThe association between serum ferritin and nonalcoholic fatty liver disease (NAFLD) in children with obesity is not clear. This study was designed to investigate whether serum ferritin can be an independent predictor for NAFLD.MethodsAccording to the hepatic ultrasound results, a total of 347 children with obesity were enrolled in this study. Among them, 95 patients with NAFLD and 95 without NAFLD were matched for gender, age, blood pressure and body mass index, the odds ratios (OR) and 95% confidence intervals (CI) for the association of ferritin and the risk of NAFLD were analyzed.ResultsAfter propensity score matching, ferritin values of the patients with NAFLD were significantly higher than those without NAFLD group. Alanine aminotransferase and ferritin were strongly associated with NAFLD in multivariate stepwise logistic regression analysis. The medium and high levels of ferritin increased risk of NAFLD, and the adjusted ORs were 3.298 (95% CI:1.326‐8.204), 7.322 (95% CI:2.725‐19.574) across the ferritin concentration tertiles after adjustment for confounders. Ferritin was shown to be the best predictor for NAFLD with sensitivity and specificity of 60.0% and 77.9%, respectively, area under the curve was 0.733.ConclusionThe results show that serum ferritin can usefully be considered as a predictor of NAFLD in children with obesity. 相似文献