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1.
目的 考察注射用丹参多酚酸(SAFI)对脑缺血大鼠急性期用药的可行性,明确大鼠脑缺血再灌注后脑血流的变化及其与远期运动功能恢复之间的相关性。方法 将Wistar大鼠随机分为假手术组、模型组及SAFI (21 mg·kg-1)组。SAFI组根据不同给药时机又分为3个亚组,分别是再灌后立即给药组(SAFI 0周)、再灌后1周给药组(SAFI 1周)、再灌后2周给药组(SAFI 2周),每组每天给药1次,连续ip 7 d,为保持一致性,其余时间均ip生理盐水,假手术组及模型组分别ip等量生理盐水。采用线栓法构建大鼠脑缺血再灌注模型,假手术组仅分离血管。通过观测大鼠一般状态、评估大鼠神经功能和脑梗死体积百分比考察SAFI急性期给药的药效作用;利用激光多普勒技术检测大鼠局部脑血流量(rCBF);通过转棒实验和步态实验分析大鼠的运动能力;通过Pearson相关性分析方法评估不同时间点的脑血流变化与远期运动功能恢复之间的相关性。结果 与模型组比较,SAFI 0周组大鼠的神经功能评分显著降低(P<0.01),脑梗死体积百分比显著降低(P<0.01),rCBF显著提升(P<0.05、0.01),死亡率明显下降;与模型组比较,SAFI 0周组大鼠在转棒仪上跌落潜伏期显著增加(P<0.05、0.01),SAFI 0周组大鼠在步态仪上运动速度显著增加(P<0.01),四肢的摆动时间、站立时间和步态周期显著下降(P<0.05、0.01),四肢(除左后肢外)的步幅显著增加(P<0.05、0.01)。与SAFI 1、2周组比较,SAFI 0周组脑梗死体积百分比显著降低(P<0.01),死亡率降低,rCBF显著升高(P<0.05、0.01),明显促进了神经行为学功能及运动功能的恢复。Pearson相关性分析结果表明脑缺血再灌注损伤后早期的脑血流恢复与远期运动功能呈线性相关。结论 SAFI在缺血急性期给药具有一定的可行性;脑缺血后梗死周边区域血流恢复对远期运动功能的恢复至关重要。  相似文献   
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目的采用CT双气相配准技术对无症状吸烟者的肺小气道病变进行定量分析,并探讨其与肺功能的相关性。资料与方法前瞻性收集延安大学附属医院2019年9月—2020年10月正常健康体检不吸烟者34例、低吸烟指数者28例和高吸烟指数者33例,行呼、吸双相CT扫描,将原始数据导入数字肺定量分析软件进行配准并小气道分析,得出CT定量指标:正常肺组织(Normal%)、小气道病变(fSAD%)、肺气肿(Emph%)、吸气相小于-950 Hu体素百分比(IN-950%)、吸气相平均肺密度(MLD-IN)、呼气相小于-856 Hu体素百分比(EX-856%)、呼气相平均肺密度(MLD-EX)。3组间CT定量指标和肺功能指标呼气峰流速(PEF)、1 s末用力呼气容积实测值占预计值百分比(FEV1%)、FEV1占用力肺活量的百分比(FEV1/FVC)的差异采用单因素方差分析或非参数检验,并分析CT定量指标与肺功能的相关性。结果3组间CT定量指标IN-950%、MLDIN差异无统计学意义(Z=2.106、1.367,P>0.05),Normal%(F=46.506,P=0.000)、fSAD%(F=57.126,P=0.000)、Emph%(Z=53.140,P=0.000)、MLD-EX(Z=14.902,P=0.000)、EX-856%(Z=15.902,P=0.000)比较,差异有统计学意义。3组间肺功能指标PEF(F=14.376,P=0.001)、FEV1%(Z=7.559,P=0.023)、FEV1/FVC(Z=25.856,P=0.000)差异有统计学意义。3组fSAD%指标吸烟指数由低到高分别为10.39%、13.67%、25.71%,Emph%指标分别为3.65%、4.67%、10.55%。随着吸烟指数增加,Normal%、MLD-EX、PEF、FEV1%、FEV1/FVC逐渐下降,fSAD%、Emph%、EX-856%逐渐上升。吸烟者CT定量指标Normal%、fSAD%、Emph%、MLD-EX、EX-856%与肺功能PEF和FEV1/FVC均有相关性(P<0.05)。fSAD%与肺功能指标FEV1/FVC的相关性最高(r=-0.576,P=0.000),其次是Emph%(r=-0.565,P=0.000)。结论基于双气相配准定量CT能测量无症状吸烟者的肺内小气道病变,fSAD%、Emph%能更敏感地发现无症状吸烟者的肺功能改变。  相似文献   
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We read with interest the commentary by Skeldon and Dijk about our article “Weekly, seasonal and chronotype-dependent variation of dim light melatonin onset.” The discussion points raised by Skeldon and Dijk are currently among the most hotly debated in human circadian science. What external factors determine human phase of entrainment? How great is the contribution of natural versus artificial light and sun time versus social time? Our intra-individual data add to the still limited evidence from field studies in this matter. In their commentary, Skeldon and Dijk formulate two either-or hypotheses, postulating that humans entrain either solely to the natural light-dark cycle (sun time referenced by midday) (H1) or solely to the light selected by local clock time and social constraints (H2). Neither hypothesis accounts for the effect of season on human light exposure. We interpreted our findings along more complex lines, speculating that the 1-h earlier melatonin rise in summer found in our sample is likely the combined result of daylight saving time (DST)-induced behavioral advances and a stronger natural zeitgeber in summer (light exposure determined by social and seasonal factors, Horiginal). Here, we show how the criticism by Skeldon and Dijk is based on two sentences quoted out of context (misrepresenting our hypothesis as H1) and that their hypothesis H2 leaves out important seasonal components in light exposure.  相似文献   
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目的 探讨延长基础试验时间对神经介导性晕厥(neurally mediated syncope,NMS)患者直立倾斜试验(head-up tilt test, HUTT)阳性率的影响。方法 连续选取2019年4—10月在大连医科大学附属第一医院门诊及住院考虑神经介导性晕厥患者82例,交替顺序分为30 min基础试验组和45 min基础试验组。比较两组患者的试验结果阳性率、阳性反应分型、晕厥或晕厥前兆发作时间等。结果 30 min基础试验组阳性反应23例(56.1%),45 min基础试验组阳性反应24例(58.5%),两组阳性率无明显差异。基础试验阶段呈阳性反应9例,均为45 min基础试验组患者。其余73例(89%)需药物激发进行阳性结果诊断。总阳性反应类型在两组间无明显差异,以血管抑制型多见。药物激发后发生阳性反应时间在两组间差异有统计学意义[(4.96±3.2)min vs (7.93±3.1)min,P<0.01],30 min基础试验组多发生在含药5 min之内,45 min基础试验组阳性反应时间多发生在5 min之后。45 min基础试验组较30 min基础试验组阳性病例检查总时间明显延长[(52.93±3.1)min vs (34.67±1.3)min,P<0.05]。结论 45 min基础时程HUTT较30 min基础时程HUTT可增加10%的无药物激发阳性反应者,但诊断NMS整体阳性率并未提高。45 min基础试验组患者行药物激发阳性反应时间推迟,总检查时间明显延长。大多数NMS患者可以通过30 min基础时程HUTT获得确定诊断。  相似文献   
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王亚飞  洪名云 《安徽医学》2022,43(5):539-544
目的 探讨卵泡期长效长方案中扳机日血清孕酮水平对胚胎质量、妊娠结局的影响,探索导致扳机日血清孕酮水平升高的影响因素。方法 对安徽医科大学附属妇幼保健院生殖医学中心511例行卵泡期长效长方案降调节促排卵方案助孕周期资料进行回顾性分析,以扳机日血清孕酮1.5 ng/mL为界值分为A组(孕酮 ≥ 1.5 ng/mL)与B组(孕酮<1.5 ng/mL),比较A、B组获卵数及胚胎质量的差异;再将511例周期资料中所有新鲜胚胎移植周期根据孕酮水平分为A1组(孕酮 ≥ 1.5 ng/mL)与B1组(孕酮<1.5 ng/mL),比较两组妊娠结局差异;使用二元logistic回归分析探讨影响扳机日血清孕酮升高的相关因素,应用受试者工作特征(ROC)曲线分析危险因素的预测价值。结果 A、B组间正常受精率、优质胚胎率差异无统计学意义(P>0.05);A组的获卵数(14.11±5.47)枚、成熟卵子数(11.77±4.79)枚、正常卵子受精数[(9.35±4.70)个]高于B组获卵数(9.46±4.31)枚、成熟卵子数(7.81±3.94)枚、正常卵子受精数[(6.28±3.44)个],差异有统计学意义(P<0.05)。A1组胚胎着床率(21.21%)、临床妊娠率(31.25%)均低于B1组胚胎着床率(42.00%)、临床妊娠率(57.89%),差异有统计学意义(P<0.05)。身体质量指数(OR=0.873,95%CI:0.808~0.942)和获卵数(OR=1.226,95%CI:1.169~1.286)均是扳机日血清孕酮升高的影响因素(P<0.05)。ROC曲线分析显示,身体质量指数可用于诊断扳机日血清孕酮水平升高,其曲线下面积为0.606(95%CI:0.557~0.656),约登指数最大值所对应的身体质量指数值为21.38 kg/m2,该值的敏感度为58.9%,特异度为58.5%。结论 扳机日血清孕酮升高会降低着床率及临床妊娠率,但不影响胚胎质量。身体质量指数和获卵数是扳机日血清孕酮水平升高的影响因素。  相似文献   
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IntroductionSeptic arthritis is a serious orthopaedic emergency that must be diagnosed and managed early to prevent devastating complications. The current gold standard for diagnosing septic arthritis is synovial fluid culture, but results are delayed by 48–72 h, and the sensitivity of the test is very low. Differentiating Septic from non-septic arthritis is vital to prevent unnecessary use of antibiotics and prevent complications. Serum Procalcitonin (PCT) is a useful marker in differentiating septic from non-septic arthritis but there are very few studies that have studied the role of synovial PCT for the same.AimTo determine the role of serum and synovial PCT in differentiating acute Septic from non-septic arthritis.Materials and methodsProspective clinical study in which 60 patients presenting with acute inflammatory arthritis (<2 weeks duration) were enrolled from May 2018 to May 2020. Serum and synovial fluid samples were drawn at presentation and routine blood investigations, synovial fluid culture sensitivity, and Procalcitonin levels were measured. Patients were divided into 3 groups, with group-1 having confirmed pyogenic, group-2 having presumed pyogenic, and group-3 having non –pyogenic patients, respectively. All data was tabulated and statistically analysed using appropriate tests.ResultsMean serum PCT values in groups 1, 2 and 3 were 1.06 ± 1.11, 0.85 ± 0.74, and 0.11 ± 0.24, respectively. Patients in the Pyogenic group (group1 and group 2) had significantly higher mean serum PCT as compared to group3 (p < 0.0001). Group 1 had higher serum PCT as compared to group 2, but the difference was not significant (p = 0.58). Mean synovial PCT in group 1, 2 and 3 were 2.42 ± 1.98, 1.89 ± 1.18, and 0.22 ± 0.40, respectively. Patients in the Pyogenic group (Group1 and Group2) had significantly higher mean synovial PCT as compared to Group 3 (p < 0.0001). Group 1 had higher mean synovial PCT as compared to group 2, but the difference was not significant (p = 0.54). The area under the ROC curve of the serum levels of PCT was 0.0.895, and the area under the ROC curve of the synovial fluid levels of PCT was 0.914, which was higher than the serum PCT level.ConclusionSerum and synovial Procalcitonin may be used as a diagnostic marker in differentiating septic from inflammatory arthritis and can help in reducing unnecessary use of antibiotics and early diagnosis and management of septic arthritis, thereby preventing complications.  相似文献   
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Quantitative susceptibility mapping (QSM) has the potential for being a biomarker for various diseases because of its ability to measure tissue susceptibility related to iron deposition, myelin, and hemorrhage from the phase signal of a T2*-weighted MRI. Despite its promise as a quantitative marker, QSM is faced with many challenges, including its dependence on preprocessing of the raw phase data, the relatively weak tissue signal, and the inherently ill posed relationship between the magnetic dipole and measured phase. The goal of this study was to evaluate the effects of background field removal and dipole inversion algorithms on noise characteristics, image uniformity, and structural contrast for cerebral microbleed (CMB) quantification at both 3T and 7T. We selected four widely used background phase removal and five dipole field inversion algorithms for QSM and applied them to volunteers and patients with CMBs, who were scanned at two different field strengths, with ground truth QSM reference calculated using multiple orientation scans. 7T MRI provided QSM images with lower noise than did 3T MRI. QSIP and VSHARP + iLSQR achieved the highest white matter homogeneity and vein contrast, with QSIP also providing the highest CMB contrast. Compared with ground truth COSMOS QSM images, overall good correlations between susceptibility values of dipole inversion algorithms and the COSMOS reference were observed in basal ganglia regions, with VSHARP + iLSQR achieving the susceptibility values most similar to COSMOS across all regions. This study can provide guidance for selecting the most appropriate QSM processing pipeline based on the application of interest and scanner field strength.  相似文献   
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