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1.
目的探讨超声造影定量评估脓毒症相关急性肾损伤(S-AKI)大鼠肾血流灌注及其参数对大鼠炎症反应的监测价值。 方法选取健康SD大鼠32只,平均分为模型组和对照组,模型组采用盲肠结扎穿孔术制作脓毒症大鼠,对照组仅开腹游离盲肠末端,不结扎穿孔,直接还纳关闭腹腔。于术后12 h、24 h两个时间点每组取8只大鼠行超声造影检查,并选取感兴趣区绘制时间强度曲线进行定量分析,下腔静脉取血检测血清肌酐(Scr)、尿素(Urea)、白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)、白细胞介素10(IL-10),留取肾标本进行病理检查。采用独立样本t检验和非参数检验(Mann-Whitney U)统计不同时间点两组各指标的差异,采用Spearman相关分析超声造影定量参数[造影剂到达时间(AT)、达峰时间(TTP)、上升斜率(AS)、峰值强度(PI)、降半时间(DT/2)、下降斜率(DS)、曲线下面积(AUC)]与炎症因子的相关性。 结果(1)模型组肾功能指标Scr、Urea、炎症因子指标IL-6、TNF-α、IL-10于两个时间点均显著高于对照组,差异均具有统计学意义(P均<0.05)。(2)造影剂团注后2~4 s,肾血管快速增强,随后皮质、髓质依次显影,髓质、皮质依次消退。与对照组相比,模型组12 h肾皮质TTP增加[(10.47±1.25)s vs(8.30±1.53)s],DS、PI减小[(-0.13±0.02)dB/s vs(-0.17±0.04)dB/s;(23.90±1.36)dB vs(27.26±1.88)dB],髓质TTP、DT/2增加[(11.66±1.99)s vs(9.00±1.28)s;(62.49±4.56)s vs(52.15±7.70)s],DS减小[(-0.13±0.02)dB/s vs(-0.17±0.03)dB/s],差异均有统计学意义(t=-3.105、-3.121、4.102、-3.180、-3.268,-2.915,P=0.008、0.008、0.001、0.007、0.007、0.011),模型组24 h肾皮质AS、DS增加[(0.99±0.17)dB/s vs(0.61±0.19)dB/s;(-0.23±0.03)dB/s vs(-0.15±0.04)dB/s],DT/2、AUC减小[(42.41±3.03)s vs(61.07±6.52)s;(2477.89±113.37)dB·s vs(3024.93±253.81)dB·s],髓质AS、DS、AT增加[(1.00±0.27)dB/s vs(0.66±0.17)dB/s;(-0.23±0.06)dB/s vs(-0.15±0.04)dB/s;(4.30±0.34)s vs(3.77±0.29)s],DT/2、AUC减小[(42.73±7.02)s vs(59.64±9.23)s;(2335.75±189.77)dB·s vs(2689.72±285.45)dB·s],差异具有统计学意义(t=-4.262、5.138、7.344、5.566、-3.061、3.108、-3.349、4.124、2.921,P=0.001、<0.001、<0.001、<0.001、=0.008、=0.008、=0.005、=0.001、=0.011)。(3)肾皮质超声造影定量参数PI、AUC与血清IL-6、TNF-α、IL-10呈显著相关(r=-0.562、-0.398、-0.512;-0.540、-0.638、-0.430,P均<0.05)。(4)肾病理切片行过碘酸雪夫染色显示,模型组大鼠肾出现肾小管轮廓不清、扩张、刷状缘脱落、肾小管上皮细胞扁平化、脱落表现,24 h模型组部分肾小管管型形成;对照组大鼠病理表现正常。 结论超声造影可以实时动态观察大鼠肾血流灌注过程,定量评价血流灌注水平,初步监测机体的炎症反应状态。  相似文献   
2.
目的:分析三阴性乳腺癌样本中PD-1、PD-L1的表达水平及其与肿瘤浸润性淋巴细胞及临床病理指标的相关性,探讨其临床意义。方法:免疫组织化学法检测132例乳腺浸润性导管癌患者样本中PD-1、PD-L1、CD4及CD8的表达情况;苏木精-伊红染色后计数癌间质中肿瘤浸润性淋巴细胞个数;回顾性分析病理报告中各项临床病理指标并随访患者预后。分析PD-1、PD-L1在三阴组和非三阴组中表达的差异,以及其与各指标之间的相关性。结果:相较于非三阴组,三阴性乳腺癌中PD-1(P=0.034)及PD-L1(P=0.037)高表达;三阴性乳腺癌中PD-1的表达与肿瘤浸润性淋巴细胞个数(P=0.015)、CD4表达(P=0.001)、ki-67指数(P=0.012)、淋巴结转移(P=0.027)、脉管癌栓(P=0.009)呈正相关,与月经初潮时间(P=0.031)呈负相关;PD-L1的表达与肿瘤浸润性淋巴细胞个数(P=0.022)、CD4表达(P=0.004)、 CD8表达(P=0.037)、ki-67指数(P=0.013)、体质量指数(P=0.004)、乳腺手术史或外伤史(P=0.029)呈正相关。结论:PD-1及PD-L1在三阴性乳腺癌中的表达水平显著高于非三阴组,其表达与肿瘤浸润性淋巴细胞的数目及分型相关,并与多种临床病理指标具有明确的相关性,提示PD-1、PD-L1及肿瘤浸润性淋巴细胞可以作为三阴性乳腺癌的诊断及预后评估的重要指标。  相似文献   
3.
目的:运用新型光学生物测量仪IOL Master 700测量白内障超声乳化手术前后眼部生物学参数的变化,并探讨人工晶状体(IOL)屈光度数计算公式的选择。

方法:前瞻性研究。收集2021-01/06在苏州大学附属第一医院就诊的白内障患者52例57眼。术前和术后3mo使用IOL Master 700完成眼轴长度(AL)、前房深度(ACD)、角膜曲率(Km)的测量并分析。对不同IOL公式计算时预留的目标屈光值与术后3mo全自动验光仪实际屈光值结果进行比较并分析。

结果:手术前后测量的AL平均值分别为24.20±1.86、24.09±1.86mm,术后AL缩短了0.11mm; ACD值分别为3.08±0.44、4.55±0.36mm(P<0.001),术后ACD加深1.49mm; Km值分别为44.14±1.86、44.14±1.82D(P>0.05)。术前选用Barrett Universal Ⅱ公式所测结果的屈光误差最小,其次是Holladay Ⅱ及SRK/T公式,Holladay Ⅰ公式所测结果的误差最大(P<0.05)。

结论:白内障术后AL缩短以及ACD加深,度数测算时可考虑增加0.1mm的校正因子。IOL屈光度数计算公式中Barrett Universal Ⅱ公式预测性最佳,其次是Holladay Ⅱ及SRK/T公式。  相似文献   

4.
童彤  丁海文  沈爱宗  刘圣 《中国医院药学杂志》2022,42(17):1794-1797,1816
目的: 探究优化智能配药机器人调配技术参数对成品输液质量的影响。方法: 采用多因素正交试验优化配药机器人调配注射用头孢哌酮钠舒巴坦钠的溶媒体积、转针速度、推拉次数、抽拉角度、残留稀释、静置时间、二次配药参数,考察成品输液的不溶性微粒数;测定成品输液室温8 h内pH值、渗透压和不溶性微粒数;并对比机器调配与人工调配效率、手部意外刺伤发生率、药液残留量。结果: 注射用头孢哌酮钠舒巴坦钠最佳调配技术参数为溶解过程中溶媒体积10 mL、慢速转针、推拉5次、抽拉角度180°、残留稀释1次、静置时间10 s、选择二次配药,成品输液不溶性微粒数符合药典规定;室温8 h内成品输液性状、渗透压和pH值没有显著变化;配药机器人调配的药液残留量小于人工调配,无手部意外刺伤发生,一人同时操作2台机器的调配效率高于人工调配。结论: 通过正交试验优化配药机器人调配技术参数,能够提高调配的成品输液质量。  相似文献   
5.
BackgroundTo analyse and interpret gait patterns in pathological paediatric populations, accurate determination of the timing of specific gait events (e.g. initial contract – IC, or toe-off – TO) is essential. As currently used clinical identification methods are generally subjective, time-consuming, or limited to steps with force platform data, several techniques have been proposed based on processing of marker kinematics. However, until now, validation and standardization of these methods for use in diverse gait patterns remains lacking.Research questions1) What is the accuracy of available kinematics-based identification algorithms in determining the timing of IC and TO for diverse gait signatures? 2) Does automatic identification affect interpretation of spatio-temporal parameters?.Methods3D kinematic and kinetic data of 90 children were retrospectively analysed from a clinical gait database. Participants were classified into 3 gait categories: group A (toe-walkers), B (flat IC) and C (heel IC). Five kinematic algorithms (one modified) were implemented for two different foot marker configurations for both IC and TO and compared with clinical (visual and force-plate) identification using Bland-Altman analysis. The best-performing algorithm-marker configuration was used to compute spatio-temporal parameters (STP) of all gait trials. To establish whether the error associated with this configuration would affect clinical interpretation, the bias and limits of agreement were determined and compared against inter-trial variability established using visual identification.ResultsSagittal velocity of the heel (Group C) or toe marker configurations (Group A and B) was the most reliable indicator of IC, while the sagittal velocity of the hallux marker configuration performed best for TO. Biases for walking speed, stride time and stride length were within the respective inter-trial variability values.SignificanceAutomatic identification of gait events was dependent on algorithm-marker configuration, and best results were obtained when optimized towards specific gait patterns. Our data suggest that correct selection of automatic gait event detection approach will ensure that misinterpretation of STPs is avoided.  相似文献   
6.
In this prospective study, we investigated the impact of SARS-CoV-2 infection on semen parameters in a cohort of men who had recently recovered from COVID-19. A total of 24 men who had recently recovered from mild COVID-19 were included in the study. Their semen parameters were normal before COVID-19 according to the World Health Organization 2010 reference values. Semen samples were collected from these participants in the recovery phases of COVID-19. To determine the effect of SARS-CoV-2 infection on semen parameters, the patients' pre-COVID-19 and post-COVID-19 semen analyses were compared. The mean age of the participants was 34.7 ± 6.4 years. The median interval between the positive nasopharyngeal swab test and obtaining semen samples was 111.5 (158) days. There was no significant difference in semen parameters before and after COVID-19 in terms of semen volume (p = .56), sperm concentration (p = .06), and progressive motility (p = .14). Total motility (p = .01) and total motile sperm count (p = .02) decreased significantly after SARS-CoV-2 infection compared to the pre-infection values. This study demonstrated that sperm motility and total motile sperm count were the semen parameters which showed a significant reduction in cases with a history of mild COVID-19.  相似文献   
7.
The present study aimed to elucidate the clinicopathological significance and prognostic implications of tumor–stroma ratio (TSR) in colorectal cancers (CRCs). TSRs were investigated in 266 human CRC specimens. The correlations between TSR and clinicopathological characteristics and survival were evaluated. The hypoxia-inducible factor-1α (HIF-1α) immunohistochemical expression of tumor cells and microvessel density (MVD) of stroma were compared between stroma-low and stroma-high subgroups. Results: Stroma-low was found in 185 of 266 CRCs (69.5%). Stroma-low was significantly correlated with less frequent vascular and perineural invasion and distant metastasis than stroma-high. HIF-1α of tumor cells was more highly expressed in the stroma-high subgroup than in the stroma-low subgroup. In addition, MVD was significantly higher in the stroma-high subgroup compared to the stroma-low subgroup. The stroma-low rate was increased considerably in CRCs with a mucinous component and decreased in CRCs with a micropapillary component. There were significant correlations between stroma-low and better overall and recurrence-free survivals. Similar to the literature, we observed that stroma-low was significantly correlated with favorable tumor behaviors and better survival. The microscopic examination of TSR can be useful for predicting the prognosis of CRC patients.  相似文献   
8.
目的对近距离治疗计划的剂量参数在Oncentra治疗计划系统与MIM系统间产生的差异进行分析和研究。方法选取本院的43例妇科肿瘤患者近距离治疗计划,按照临床要求所有病例的靶区D90达到处方剂量。评估参数包括:靶区体积和D90,处方剂量总体积,靶区内的处方剂量体积以及危及器官包括:直肠,膀胱,小肠的D0.01cc,D1cc,D2cc。结果计划系统中的靶区体积和处方剂量值均明显小于MIM系统中相应的值(P<0.05),两系统显示出的处方体积相差不大。MIM系统中的靶区D90(676.74±54.82)cGy小于处方剂量,危及器官的受量则正好相反,即计划系统比MIM系统中相应的参数要小,其中直肠和膀胱的D0.01cc,D1cc,D2c,小肠的D0.01cc,D2cc的在两系统显示的值的差异均有统计学意义(P<0.05)。结论不同系统间传输相同的剂量和轮廓文件,DVH参数存在一定的差异,其主要原因是在不同系统对已勾画的各种器官轮廓计算体积存在算法上的不同。基于此,建议近距离计划在CT扫描时,尽量小的层厚可以消除或减少这种差异。  相似文献   
9.
Machined surface integrity characteristics, including surface stresses, physical-mechanical properties and metallographic structures, play important roles in the fatigue performance of machined components. This work aimed at investigating the effects of machined surface integrity on high-temperature low-cycle fatigue life. The process parameters were optimized to obtain required surface integrity and fatigue life of the turning superalloy Inconel 718. The relationships between low-cycle fatigue life and machined surface integrity characterization parameters were established based on the low-cycle fatigue tests at a high temperature (650 °C). The sensitivities of turning process parameters to high-temperature low-cycle fatigue life were analyzed, and the optimization parameters were proposed with the goal of antifatigue manufacturing. Experimental results indicated that the impact order of the characterization parameters of machined surface integrity on the high-temperature low-cycle fatigue life were the degree of work hardening RHV, the residual stress in the cutting speed direction S22, the fatigue stress concentration factor Kf, the degree of grain refinement RD and the residual stress in the feed direction S33. In the range of turning parameters of the experiments in this research, the cutting speeds could be 80~110 m/min, and the feed rate could be 0.10~0.12 mm/rev to achieve a longer high-temperature low-cycle fatigue life. The results can be used for guiding the fatigue-resistant manufacturing research of aeroengine superalloy turbine disks.  相似文献   
10.
王海莹  吕冰  李辉  王顺义 《中国骨伤》2021,34(11):1016-1019
目的:探讨脊柱-骨盆矢状位参数及关节突关节角度对退变性腰椎滑脱的影响及相关性研究。方法:以2016年7月至2019年9月确诊的120例L4-L5单节段退变性滑脱患者为观察对象(滑脱组),以性别和年龄相匹配的120例L4-L5节段退变性椎管狭窄患者为对照(对照组)。通过影像学资料测量如下参数:骨盆入射角(pelvic incidence,PI),骨盆倾斜角(pelvic tilt,PT),骶骨倾斜角(sacral slope,SS),腰椎前凸(lumbar lordosis,LL),胸椎后凸(thoracic kyphosis,TK),矢状面平衡(sagittal vertical axis,SVA),L4-L5头侧关节突关节角,尾侧关节突关节角及小关节不对称性。比较两组患者参数的差异并对有意义参数行Logistic回归分析。对退变性腰椎滑脱患者关节突关节方向与脊柱-骨盆参数进行相关性分析。结果:两组患者在PI、PT、LL、SVA、头侧关节突关节角、尾侧关节突关节角差异有统计学意义(P<0.05);Logistic回归分析发现PI、PT及头侧关节突关节角是腰椎滑脱程度的危险因素(P<0.05)。滑脱组头侧关节突关节矢状化与PI、PT呈现显著相关(P<0.05)。结论:高PI、PT及头侧关节突关节矢状化是腰椎滑脱的危险因素,并且关节突关节矢状化程度和大PI、PT密切相关。  相似文献   
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