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1.
目的:建立UPLC-MS/MS分析方法同时测定玳玳果黄酮降脂提取物效应组分新橙皮苷和柚皮苷在大鼠10种脏器组织中含量,分布规律及特征。方法:采用UPLC-MS/MS技术建立提取物效应组分新橙皮苷及柚皮苷在大鼠心、肝、脾、肺、肾、脑、胃、小肠、脂质、肌肉组织中的定量分析方法;大鼠给药后分别于0.33,0.67,1,4,8 h的5个时间点,分别摘取以上10种脏器组织,测定脏器组织及血液中效应组分的质量浓度,采用DAS(V 2.0)药动学软件对各样本的药物浓度-时间数据进行房室拟合,并计算不同组织效应组分的药-时曲线下面积(AUC)及平均滞留时间(MRT)。结果:所建立的UPLC-MS/MS定量分析方法具备良好的专属性、标准曲线及线性范围良好、方法准确度与精密度、定量下限均符合有关规定;玳玳果黄酮降脂提取物效应组分在血液中的分布符合一室模型,除肾脏及脑组织外,其余脏器中提取物效应组分的房室特征多为静脉注射的二室模型,柚皮苷在肾脏中的拟合结果为非静脉注射的二室模型,新橙皮苷在脑组织拟合结果为静脉注射的三室模型,给药后8 h各组织中效应组分新橙皮苷及柚皮苷AUC值大小顺序均为小肠 > 胃 > 肾 > 脂质 ≈ 脾脏 > 肺 > 肌肉 > 肝 > 心 > 脑,效应组分在各脏器中均无明显蓄积;效应组分在血液、肾脏、肝脏中的滞留时间较长,MRT均大于2 h,脂质最短,MRT不足1 h;各脏器中新橙皮苷的药-时曲线下面积约是柚皮苷的3倍,而心、肝、肾中则是3.5,2.1和3.4倍。结论:玳玳果黄酮降脂提取物效应组分在大鼠组织中分布迅速,达峰时间早于血液;效应组分在肠道内消除缓慢,给药8 h后在各脏器中的含量均显著下降且无特异的蓄积部位。研究结果揭示玳玳果黄酮降脂提取物效应组分在大鼠体内的分布特征及规律,为进一步理解玳玳果黄酮降脂提取物在体内的作用靶点及机制奠定了基础。 相似文献
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毛细胞白血病(HCL)是一种以脾大、全血细胞减少、骨髓组织增生等为临床表现的罕见慢性B淋巴细胞增殖性疾病。克拉屈滨作为其一线药物,对HCL的完全缓解率很高。本文报道了2017-09-04绍兴市人民医院收治的1例经典型HCL患者在克拉屈滨治疗期间,出现严重粒细胞缺乏伴高热,合并全身皮疹及间质性肺炎,经大剂量激素等治疗后好转的诊疗过程。并结合文献回顾了HCL的诊断及治疗方法,简述了克拉屈滨治疗HCL致间质性肺炎这一少见并发症的诊疗思路,以提高临床医师对该毒副作用的认识,为临床工作提供帮助。 相似文献
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A typical time series in functional magnetic resonance imaging (fMRI) exhibits autocorrelation, that is, the samples of the time series are dependent. In addition, temporal filtering, one of the crucial steps in preprocessing of functional magnetic resonance images, induces its own autocorrelation. While performing connectivity analysis in fMRI, the impact of the autocorrelation is largely ignored. Recently, autocorrelation has been addressed by variance correction approaches, which are sensitive to the sampling rate. In this article, we aim to investigate the impact of the sampling rate on the variance correction approaches. Toward this end, we first derived a generalized expression for the variance of the sample Pearson correlation coefficient (SPCC) in terms of the sampling rate and the filter cutoff frequency, in addition to the autocorrelation and cross‐covariance functions of the time series. Through simulations, we illustrated the importance of the variance correction for a fixed sampling rate. Using the real resting state fMRI data sets, we demonstrated that the data sets with higher sampling rates were more prone to false positives, in agreement with the existing empirical reports. We further demonstrated with single subject results that for the data sets with higher sampling rates, the variance correction strategy restored the integrity of true connectivity. 相似文献
5.
The cingulum, connecting the orbitofrontal cortex to the medial temporal lobe, involves in diverse cognition functions including attention, memory, and motivation. To investigate the relationship between the cingulum injury and cognitive impairment in patients with chronic mild traumatic brain injury, we evaluated the integrity between the anterior cingulum and the basal forebrain using diffusion tensor tractography in 73 patients with chronic mild traumatic brain injury(39 males, 34 females, age 43.29 ± 11.42 years) and40 healthy controls(22 males, 18 females, age 40.11 ± 16.81 years). The patients were divided into three subgroups based on the integrity between the anterior cingulum and the basal forebrain on diffusion tensor tractography: subgroup A(n = 19 patients)-both sides of the anterior cingulum were intact; subgroup B(n= 36 patients)-either side of the anterior cingulum was intact; and subgroup C(18 patients)-both sides of the anterior cingulum were discontinued. There were significant differences in total Memory Assessment Scale score between subgroups A and B and between subgroups A and C. There were no significant differences in diffusion tensor tractography parameters(fractional anisotropy, apparent diffusion coefficient, and fiber volume) between patients and controls. These findings suggest that the integrity between the anterior cingulum and the basal forebrain, but not diffusion tensor tractography parameter, can be used to predict the cognitive function of patients with chronic mild traumatic brain injury. This study was approved by Yeungnam University Hospital Institutional Review Board(approval No. YUMC-2014-01-425-010) on August 16, 2017. 相似文献
6.
Su Jeong Seong Jin Pyo Hong Bong-Jin Hahm Hong Jin Jeon Jee Hoon Sohn Jun Young Lee Maeng Je Cho 《Journal of Korean medical science》2015,30(11):1675-1681
While decreasing trend in gender differences in alcohol use disorders was reported in Western countries, the change in Asian countries is unknown. This study aims to explore the shifts in gender difference in alcohol abuse (AA) and dependence (AD) in Korea. We compared the data from two nation-wide community surveys to evaluate gender differences in lifetime AA and AD by Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Face-to-face interviews using the Composite International Diagnostic Interview (CIDI) were applied to all subjects in 2001 (n=6,220) and 2011 (n=6,022). Male-to-female ratio of odds was decreased from 6.41 (95% CI, 4.81-8.54) to 4.37 (95% CI, 3.35-5.71) for AA and from 3.75 (95% CI, 2.96-4.75) to 2.40 (95% CI, 1.80-3.19) for AD. Among those aged 18-29, gender gap even became statistically insignificant for AA (OR, 1.59; 95% CI, 0.97-2.63) and AD (OR, 1.18; 95% CI, 0.80-2.41) in 2011. Men generally showed decreased odds for AD (0.55; 95% CI, 0.45-0.67) and women aged 30-39 showed increased odds for AA (2.13; 95% CI 1.18-3.84) in 2011 compared to 2001. Decreased AD in men and increased AA in women seem to contribute to the decrease of gender gap. Increased risk for AA in young women suggests needs for interventions. 相似文献
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目的:通过逆行神经追踪法研究大鼠骶髂关节的传入神经通路。方法:30只雄性Sprague-Dawley大鼠随机分成非交感神经切除组(A组)和交感神经切除组(B组),每组15只,交感神经切除组切除左侧L1以下椎旁交感干。两组左侧骶髂关节注入30%的辣根过氧化物酶(HRP)20μl,72h后取出双侧的L1-S1背根神经节(DRG),TMB法染色后在光学显微镜下观察HRP阳性神经元细胞并计数。结果:两组左侧L1、L2背根神经节内HRP阳性神经元差异有显著性意义(P<0·05),B组HRP阳性神经元明显减少;左侧L3-S1背根神经节内HRP阳性神经元差异无显著性意义(P>0·05)。结论:L1-S1神经节含有支配同侧骶髂关节的传入神经元,同侧椎旁交感干可能是骶髂关节到L1-L2神经节重要的传入神经旁路,而不是到L3-L5神经节的传入旁路或重要的传入旁路。 相似文献
9.
胸腺内注射异基因抗原诱导鼠神经移植免疫耐受的实验研究 总被引:15,自引:0,他引:15
目的探讨小鼠胸腺内注射异基因抗原在同种异体异基因坐骨神经移植免疫耐受中的作用。方法自供体小鼠C57BL/6的脾细胞中提取MHC抗原注人受体鼠Balb/c小鼠胸腺内,于2周后移植供体鼠坐骨神经。48只Balb/c小鼠随机分为4组,A组(胸腺内注射组)、B组(自体神经移植组)、C组(冷冻异体神经移植组)、D组(异体神经移植加用免疫抑制剂组)。于3周后进行电生理学、组织学、免疫学检测。结果A组运动神经传导速度(38.23m/s)与D组(36.39m/s)相比无显著性差异(P〉0.05),组织学、电镜、免疫学(混合淋巴细胞培养及迟发性超敏反应)检测结果均证实B组分别优于A组、D组和C组。结论胸腺内注射异基因MHC抗原可诱导大鼠对异体坐骨神经移植的特异性免疫耐受。 相似文献
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