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41.
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   
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目的 探索黄芩素调控核苷酸结合寡聚化结构域样受体蛋白 3 ( nucleotide-binding oligomerization domain-like receptor protein 3, NLRP3) / 半胱氨酸天冬氨酸蛋白酶 1 ( cysteine aspartate protease 1, Caspase1) 通路对牙周炎大鼠牙槽骨吸收的影响。 方法 将 40 只牙周炎大鼠随机分为模型组、 黄芩素组、 激活剂 组、 黄芩素 + 激活剂组, 另取 10 只正常作为对照组。 检测大鼠釉牙骨质界到牙槽嵴顶 (CEJ-AC) 的距离、 血清中白细胞介素-6 (IL-6)、 转化生长因子-β (TGF-β) 含量以及牙周组织病理变化、 IL-6、 TGF-β 阳性 表达和 NLRP3、 Caspase-1 蛋白表达。 结果 模型组大鼠 CEJ-AC、 NLRP3、 Caspase-1、 IL-6、 TGF-β 水平及 阳性表达水平以及蛋白表达水平均升高 (P< 0. 05); 经黄芩素干预后, 各项指标均降低 (P< 0. 05); 引入 激活剂明显削弱了黄芩素对牙周炎大鼠的抗炎作用。 结论 黄芩素通过抑制 NLRP3 / Caspase-1 通路减轻炎性反应, 控制牙槽骨吸收。  相似文献   
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目的:探讨原发灶不明骨髓转移癌的病例特点、治疗情况及预后。方法:对纳入的25例患者进行回顾性分析其各自的临床特点、治疗过程以及生存情况。结果:25例患者中位总生存期为6个月。初诊时是否伴有血液学症状、病理类型、治疗方式以及接受治疗时间对患者生存有显著差异。治疗方式、家庭支持强度是影响预后的独立因素。结论:原发灶不明骨髓转移癌是临床少见的疾病,给予积极的综合治疗,加强社会家庭的支持强度可能会改善其预后。  相似文献   
46.
ObjectiveTo investigate the association between type 1 diabetes mellitus (T1D) and type 2 diabetes mellitus (T2D) with risk of sudden cardiac arrest (SCA).MethodsIn a prospective community-based study of SCA from February 1, 2002, through November 30, 2019, we ascertained 2771 cases age 18 years of age or older and matched them to 8313 controls based on geography, age, sex, and race/ethnicity. We used logistic regression to evaluate the independent association between diabetes, T1D, T2D, and SCA.ResultsPatients had a mean age of 64.5±15.9 years, were 33.3% female and 23.9% non-White race. Overall, 36.7% (n=1016) of cases and 23.8% (n=1981) of controls had diabetes. Among individuals with diabetes, the proportion of T1D was 6.5% (n=66) among cases and 2.0% among controls (n=40). Diabetes was associated with 1.5-times higher odds of SCA. Compared with those without diabetes, the odds ratio and 95% CI for SCA was 4.36 (95% CI, 2.81 to 6.75; P<.001) in T1D and 1.45 (95% CI, 1.30 to 1.63; P<.001) in T2D after multivariable adjustment. Among those with diabetes, the odds of having SCA were 2.41 times higher in T1D than in T2D (95% CI, 1.53 to 3.80; P<.001). Cases of SCA with T1D were more likely to have an unwitnessed arrest, less likely to receive resuscitation, and less likely to survive compared with those with T2D.ConclusionType 1 diabetes was more strongly associated with SCA compared with T2D and had less favorable outcomes following resuscitation. Diabetes type could influence the approach to risk stratification and prevention of SCA.  相似文献   
47.
目的    应用锥形束CT(cone beam CT,CBCT)测量种植区牙槽骨质量并结合Lekholm和Zarb分类法对骨质量分类方法进行改良,以期为提高牙槽骨质量分类的准确性提供指导。方法    选择2015年10月至2017年10月在呼和浩特市口腔医院种植科进行种植修复的196例患者术前CBCT影像资料,应用 Invivo5诊断设计软件测量306个种植位点的牙槽骨皮质骨厚度和松质骨密度(皮质骨与松质骨的CT值差值),以Lekholm和Zarb分类法为基础结合测量数据对骨质量进行改良后的量化分类。结果    牙槽骨皮质骨厚度为0.18 ~ 2.89 mm,中位数为0.92 mm。皮质骨与松质骨的CT值差值为88.5 ~ 667.8 HU,应用百分位数法找到33.3%和66.6%对应的数值分别为297.8 HU和356.1 HU。依据此数据结合Lekholm和Zarb分类法将196例患者的306个种植位点骨质量分为4类,其中Ⅰ类骨种植位点46个(占15.0%),Ⅱ类骨104个(占34.0%),Ⅲ类骨114个(占37.3%),Ⅳ类骨42个(占13.7%)。结论    结合Lekholm和Zarb分类法,应用CBCT测量种植区牙槽骨质量并进行分类方法的改良,可为临床医生术前评估牙槽骨质量提供一定参考。  相似文献   
48.
《Injury》2023,54(2):318-328
PurposeThis study intended to determine the properties of induced membranes after various periods of polymethyl methacrylate (PMMA) retention and the effect of different retention intervals on subsequent defect repair.MethodsModel of a critical bone defect in rabbits was prepared to obtain the induced membrane. For varying intervals of spacer insertion (2, 4, 6, 8, 12, 16, and 20 weeks postoperatively), angiogenesis, osteogenesis, and MSC-related properties were analyzed by immunohistochemistry and western-blot. Furthermore, 2, 4, 6, and 8 weeks after PMMA insertion, bone grafting was performed. Characteristics of defect repair were analyzed by X-ray and micro-CT analysis.ResultsThe induced membrane displayed angiogenesis, osteogenesis, and MSC-related properties from the 2- to 20-week intervals. Quantitation of protein expression (RUNX2, ALP, VEGF, TGF-beta, OCT4, and STRO1) revealed that selected proteins gradually rose to a high level at 4–8 weeks postoperatively and then decreased to a low level over a long time period. Following bone grafting, the most new bone formation was in the group when grafting was performed at 4 weeks, followed by the groups at 2 and 6 weeks, with the least in the group at 8 weeks.ConclusionThe induced membrane displays angiogenesis, osteogenesis, and MSC-related properties from the 2- to 20-week intervals. These were increased to a peak level at 4–8 weeks postoperatively and then gradually decreased. The optimal timing for bone grafting at the second stage in the presented model was 4 weeks after PMMA insertion.  相似文献   
49.
《Vaccine》2022,40(24):3320-3329
BackgroundCurrently, booster dose is needed after 2 doses of non-live COVID-19 vaccine. With limited resources and shortage of COVID-19 vaccines, intradermal(ID) administration might be a potential dose-sparing strategy.ObjectiveTo determine immunologic response and reactogenicity of ID ChAdOx1 nCoV-19 vaccine (AZD1222,Oxford/AstraZeneca) as a booster dose after completion of 2-dose CoronaVac(SV) in healthy adult.MethodsThis is a prospective cohort study of adult aged 18–59 years who received 2-dose SV at 14–35 days apart for more than 2 months. Participants received ID AZD1222 at fractional low dose(1×1010 viral particles,0.1 ml). Antibody responses were evaluated by surrogate virus neutralization test(sVNT) against delta variant and wild type, and anti-spike-receptor-binding-domain immunoglobulin G(anti-S-RBD IgG) at prior, day14, 28, 90, and 180 post booster. Solicited reactogenicity was collected for 7 days post-booster. Primary endpoint was the differences of sVNT against delta strain ≥ 80% inhibition at day14 and 90 compared with the parallel cohort study of 0.5-ml intramuscular(IM) route.ResultsFrom August2021, 100 adults with median age of 46 years(IQR 41–52) participated. Prior to booster, geometric mean(GM) of sVNT against delta strain was 22.4% inhibition(95 %CI 18.7–26.9) and of anti-S-RBD IgG was 109.3 BAU/ml(95.4–125.1). Post ID booster, GMs of sVNT against delta strain were 95.5% inhibition (95%CI 94.2–96.8) at day14, 73.1% inhibition (66.7–80.2) at day90, and 22.7% inhibition (14.9–34.6) at day180. The differences of proportion of participants achieving sVNT against delta strain ≥ 80% inhibition in ID recipients versus IM were + 4.2% (95 %CI -2.0to10.5) at day14, and ?37.3%(-54.2to-20.3) at day90. Anti-S-RBD IgG GMs were 2037.1 BAU/ml (95%CI 1770.9–2343.2) at day14 and 744.6 BAU/ml(650.1–852.9) at day90, respectively. Geometric mean ratios(GMRs) of anti-S-RBD IgG were 0.99(0.83–1.20) at day14, and 0.82(0.66–1.02) at day90. Only 18% reported feverish, compared with 37% of IM (p = 0.003). Common reactogenicity was erythema at injection site(53%) while 7% reported blister.ConclusionLow-dose ID AZD1222 booster enhanced lower neutralizing antibodies at 3 months compared with IM route. Less systemic reactogenicity occurred, but higher local reactogenicity.  相似文献   
50.
Optimizing the environment of complex bone healing and improving treatment of catastrophic bone fractures and segmental bone defects remains an unmet clinical need both human and equine veterinary medical orthopaedics. The objective of this study was to determine whether scAAV‐equine‐BMP‐2 transduced cells would induce osteogenesis in equine bone marrow derived mesenchymal stem cells (BMDMSCs) in vitro, and if these cells could be cryopreserved in an effort to osteogenically prime them as an “off‐the‐shelf” gene therapeutic approach for fracture repair. Our study found that transgene expression is altered by cell expansion, as would be expected by a transduction resulting in episomal transgene expression, and that osteoinductive levels could still be achieved 5 days after recovery, and protein expression would continue up to 14 days after transduction. This is the first evidence that cryopreservation of genetically modified BMDMSCs would not alter the osteoinductive potential or clinical use of allogeneic donor cells in cases of equine fracture repair. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1310–1317, 2019.  相似文献   
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