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61.
《Brain & development》2019,41(8):671-677
ObjectiveWe sought to develop and validate a novel scoring system for the prediction of severe intraventricular hemorrhage (SIVH) in very low birth weight infants (VLBWI).MethodsThis retrospective cohort multicenter study included 615 VLBWI born between 24 and 32 weeks gestational age (GA). Multivariable logistic regression analyses were used to determine which factors evaluated within the first 5 days of life were associated with SIVH and the weights of these variables. The accuracy of the predictive scoring system was prospectively tested in the same units.ResultsThe final SIVH scoring system included the following variables: antenatal steroid therapy, GA, birth weight (BW), 1-min Apgar score, mechanical ventilation and hypotension. The SIVH scores used to divide the subjects into three tiers (low-risk (<5), moderate-risk (5–8) and high-risk (>8)) were developed based on these variables. Of infants with a score below 5, 1.2% (4/339) developed SIVH. Of those with a score above 8, 42.5% (17/40) developed SIVH. The scores were successfully verified in 99 VLBWI.ConclusionsThese findings suggest that among infants with a score >8, the incidence of SIVH is significantly higher. This scoring system can be used to predict the incidence of SIVH during the first 5 days after birth and may contribute to the early intervention in and prevention of SIVH. 相似文献
62.
Mark I. Evans Robert D. Eden David W. Britt Barry S. Schifrin 《The journal of maternal-fetal & neonatal medicine》2019,32(15):2561-2569
Background: Even key opinion leaders now concede that electronic fetal monitoring (EFM) cannot reliably identify fetal acidemia which many vouch as the only labor mediated pathophysiologic precursor for cerebral palsy (CP). We have developed the “Fetal Reserve Index” – an algorithm combining five dynamic components of EFM (1. Rate, 2. Variability, 3. Accelerations, 4. Decelerations, and 5. Excessive uterine activity) considered individually that are combined with the presence of: 6. maternal, 7. obstetrical, and 8. fetal risk factors.Objective: Here, we compare this 8-point fetal reserve index (FRI) against the performance of ACOG monograph criteria and ACOG Category systems for predicting risk for both CP and the need for emergency operative delivery (EOD). We then studied how varied management for screen positives (Red zone-defined below) impacts the outcome of such cases.Study design: Four hundred twenty term patients were studied: all entered labor with normal EFMs and no apparent cause of harm except events of labor and delivery. Sixty subsequently developed CP, and 360 were apparently normal controls. An FRI, normal on all eight parameters scored 100%, 4 of the 8 was 50%, etc. We divided cases into Green zone >50%, Yellow 50–26%, and Red ≤25%. An FRI in the Red zone was considered a positive screen. We then compared performance metrics for the three evaluation schemes and differences between controls that reached Red against those controls whose worst scores were Green/Yellow.Results: For detection of injury during labor, the FRI performed much better than the ACOG Category criteria (sensitivity 28%), and Category III (45%) (p?.001). All CP cases reached Red zone and were Red for a minimum of 2 hours (mean?=?5.35 hours). Twenty-four% of controls reached Red, but were only Red for average of 1?hr. The incidence of low Apgar’s, pH, FRI, and Lowest FRI increased progressively from Green/Yellow controls to red controls to CP cases. Irrespective, CP cases met ACOG Monograph criteria for labor injury less than 50% of the time. Only half of CP babies had umbilical artery pH values <7.00, and less than 50% showed Category III patterns. The earlier in labor the Red zone was reached, the more likely for a baby to develop CP or the mother to require an EOD regardless of fetal outcome. Successful intrauterine resuscitations (IR) diminished time spent in the Red zone and the need for EODs.Conclusions: FRI shows better discrimination for adverse fetal outcome and EOD than traditional EFM interpretation. The Category system is a very poor, subjective screening method as the vast majority of CP babies never reach the “action point” result of Category III. While reaching the Red zone does not ordain a bad outcome, how it is managed, does. Compared to CP cases, Red controls were delivered faster, had higher FRIs, and often had prompt management including IR maneuvers, which improved the FRI and lowered the risk of EODs even for cases with normal outcomes. With further study and validation, the quantitative FRI approach may replace the current, very subjective interpretation with a quantitative “lab test” approach. 相似文献
63.
64.
【摘要】 血浆肾上腺髓质素(ADM)是一种具有多种生物学活性的内源性肽,以自分泌、旁分泌和内分泌的方式发挥功能和作用,包括舒张血管、降低血压、扩张支气管平滑肌细胞、改善微循环、稳定血管内皮功能、调节肺动脉压、调节炎症及免疫功能、参与多种激素的分泌和调节等作用,因最初在肾上腺嗜铬细胞瘤组织中发现而得名。后来发现其在多种器官、组织均有表达,包括心、脑、肾、肿瘤组织等,尤其在内皮细胞、血管平滑肌细胞等表达含量较高,在人体肺组织中也广泛存在。目前许多研究已发现肾上腺髓质素可能参与某些肺部疾病的病理生理过程,包括社区获得性肺炎、支气管哮喘、慢性阻塞性肺部疾病、肺动脉高压、肺部肿瘤等疾病。本文就肾上腺髓质素在呼吸系统相关性疾病方面的研究进展作一综述。 相似文献
65.
66.
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
67.
68.
目的对比达芬奇机器人与传统腹腔镜在治疗小儿先天性胆总管囊肿的优劣势。方法回顾性收集2018年3月至2019年9月郑州大学第一附属医院诊断为胆总管囊肿的103例患儿的临床资料,其中行达芬奇机器人手术的21例患儿作为机器人组,行传统腹腔镜治疗的82例患儿为腹腔镜组,所有手术均由同一团队完成。其中,机器人组患儿的年龄为(3.85±0.79)岁,范围为1~11岁;Todani分型为胆总管囊性扩张型(Ⅰ型)17例,其他分型4例;囊肿最大径为(36.76±10.13)mm,范围为16~79 mm。腹腔镜组患儿的年龄为(3.71±0.67)岁,范围为3个月至12岁;Todani分型为Ⅰ型70例,其他分型12例;囊肿最大径为(35.98±8.25)mm,范围为10~82 mm。分析两组在一般资料及术前情况、术中及术后等方面的差异。结果①机器人组与腹腔镜组患儿在年龄、性别、体重、临床表现、Todani分型、囊肿最大径、术前C反应蛋白(C-reactive protein,CRP)值、术后并发症发生率、术后疼痛评分方面差异无统计学意义(P>0.05);②机器人组的术中失血量、术后第一天及第三天腹腔引流液量、术后CRP值、术后禁食时间、术后出院时间均小于腹腔镜组,差异具有统计学意义(P<0.05)。结论达芬奇机器人在治疗小儿先天性胆总管囊肿方面较传统腹腔镜具有术中出血量少、组织损伤小、恢复快、愈合好等优点,具有可行性、安全性、有效性等优点。不足之处为手术总时间较长、费用较高。随着技术的进步及手术医生经验的积累,机器人治疗小儿先天性胆总管囊肿将会发挥更大的优势。 相似文献
69.
《Journal of vascular and interventional radiology : JVIR》2022,33(3):324-332.e2
PurposeTo show that a deep learning (DL)–based, automated model for Lipiodol (Guerbet Pharmaceuticals, Paris, France) segmentation on cone-beam computed tomography (CT) after conventional transarterial chemoembolization performs closer to the “ground truth segmentation” than a conventional thresholding-based model.Materials and MethodsThis post hoc analysis included 36 patients with a diagnosis of hepatocellular carcinoma or other solid liver tumors who underwent conventional transarterial chemoembolization with an intraprocedural cone-beam CT. Semiautomatic segmentation of Lipiodol was obtained. Subsequently, a convolutional U-net model was used to output a binary mask that predicted Lipiodol deposition. A threshold value of signal intensity on cone-beam CT was used to obtain a Lipiodol mask for comparison. The dice similarity coefficient (DSC), mean squared error (MSE), center of mass (CM), and fractional volume ratios for both masks were obtained by comparing them to the ground truth (radiologist-segmented Lipiodol deposits) to obtain accuracy metrics for the 2 masks. These results were used to compare the model versus the threshold technique.ResultsFor all metrics, the U-net outperformed the threshold technique: DSC (0.65 ± 0.17 vs 0.45 ± 0.22, P < .001) and MSE (125.53 ± 107.36 vs 185.98 ± 93.82, P = .005). The difference between the CM predicted and the actual CM was 15.31 mm ± 14.63 versus 31.34 mm ± 30.24 (P < .001), with lesser distance indicating higher accuracy. The fraction of volume present ([predicted Lipiodol volume]/[ground truth Lipiodol volume]) was 1.22 ± 0.84 versus 2.58 ± 3.52 (P = .048) for the current model’s prediction and threshold technique, respectively.ConclusionsThis study showed that a DL framework could detect Lipiodol in cone-beam CT imaging and was capable of outperforming the conventionally used thresholding technique over several metrics. Further optimization will allow for more accurate, quantitative predictions of Lipiodol depositions intraprocedurally. 相似文献
70.
尽管嵌合抗原受体(CAR)T细胞治疗在血液系统恶性肿瘤患者中取得了显著的临床疗效,但需要进一步优化。脂质纳米粒(LNP)-信使核糖核酸(mRNA)递送系统作为一种非病毒性基因载体运用于CAR-T细胞治疗研究中,一方面通过LNP将密封蛋白-6 mRNA靶向递送至抗原提呈细胞,从而实现抗原提呈细胞辅助性增强密封蛋白-6靶向的CAR-T细胞的功能,以进一步诱导对实体瘤的清除;另一方面,通过LNP将成纤维细胞激活蛋白(FAP)CARmRNA靶向递送至T细胞,实现体内FAP靶向的CAR-T细胞的制备,以通过阻断心脏纤维化过程达到治疗急性心肌损伤的目的。在CAR-T细胞研究和治疗中,LNP-mRNA递送系统具有不与细胞基因组整合、价格便宜、毒副作用小及可修饰等优点,亦存在蛋白瞬时表达导致调控细胞功能的持久性不足及制备等方面的技术局限性。本文综述了LNP-mRNA递送系统及其在CAR-T细胞治疗中的应用研究。 相似文献