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Neoadjuvant programmed cell death protein 1 (PD-1) blockade exhibits promising efficacy in patients with mismatch repair deficient (dMMR) colorectal cancer (CRC). However, discrepancies between radiological and histological findings have been reported in the PICC phase II trial (NCT 03926338). Therefore, we strived to discern radiological features associated with pathological complete response (pCR) based on computed tomography (CT) images. Data were obtained from the PICC trial that included 36 tumors from 34 locally advanced dMMR CRC patients, who received neoadjuvant PD-1 blockade for 3 months. Among the 36 tumors, 28 (77.8%) tumors achieved pCR. There were no statistically significant differences in tumor longitudinal diameter, the percentage change in tumor longitudinal diameter from baseline, primary tumor sidedness, clinical stage, extramural venous invasion status, intratumoral calcification, peritumoral fat infiltration, intestinal fistula and tumor necrosis between the pCR and non-pCR tumors. Otherwise, tumors with pCR had smaller posttreatment tumor maximum thickness (median: 10 mm vs 13 mm, P = .004) and higher percentage decrease in tumor maximum thickness from baseline (52.9% vs 21.6%, P = .005) compared to non-pCR tumors. Additionally, a higher proportion of the absence of vascular sign (P = .003, odds ratio [OR] = 25.870 [95% CI, 1.357-493.110]), nodular sign (P < .001, OR = 189.000 [95% CI, 10.464-3413.803]) and extramural enhancement sign (P = .003, OR = 21.667 [2.848-164.830]) was observed in tumors with pCR. In conclusion, these CT-defined radiological features may have the potential to serve as valuable tools for clinicians in identifying patients who have achieved pCR after neoadjuvant PD-1 blockade, particularly in individuals who are willing to adopt a watch-and-wait strategy.  相似文献   
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癫痫发作后状态(PIS)是指癫痫发作停止到恢复至发病前水平的异常状态,包括认知、运动、感觉、自主神经和精神行为等异常,症状多样,严重程度不一,持续数秒至数天不等,对患者的健康和生活质量产生很大影响。然而,目前国内外相关的研究较少,临床医生对此缺乏正确认识,容易误诊误治。本文将从PIS的定义、病理生理机制、临床表现、诊断和鉴别诊断、临床意义以及干预策略等进行综述,以提高临床医生的认识,并为今后临床研究提供参考。  相似文献   
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Noninvasive imaging of cardiac fibrosis is important for early diagnosis and intervention in chronic heart diseases. Here, we investigated whether noninvasive, contrast agent-free MRI T2-mapping can quantify myocardial fibrosis in preclinical models of aging and pressure overload. Myocardial fibrosis and remodeling were analyzed in two animal models: (i) aging (15-month-old male CF-1 mice vs. young 6- to 8-week-old mice), and (ii) pressure overload (PO; by transverse aortic constriction in 4- to 5-month-old male C57BL/6 mice vs. sham-operated for 14 days). In vivo T2-mapping was performed by acquiring data during the isovolumic and early diastolic phases, with a modified respiratory and ECG-triggered multiecho TurboRARE sequence on a 7-T MRI. Cine MRI provided cardiac morphology and function. A quantitative segmentation method was developed to analyze the in vivo T2-maps of hearts at midventricle, apex, and basal regions. The cardiac fibrosis area was analyzed ex vivo by picro sirius red (PSR) staining. Both aged and pressure-overloaded hearts developed significant myocardial contractile dysfunction, cardiac hypertrophy, and interstitial fibrosis. The aged mice had two phenotypes, fibrotic and mild-fibrotic. Notably, the aged fibrotic subgroup and the PO mice showed a marked decrease in T2 relaxation times (25.3 ± 0.6 in aged vs. 29.9 ± 0.7 ms in young mice, p = 0.002; and 24.3 ± 1.7 in PO vs. 28.7 ± 0.7 ms in shams, p = 0.05). However, no significant difference in T2 was detected between the aged mild-fibrotic subgroup and the young mice. Accordingly, an inverse correlation between myocardial fibrosis percentage (FP) and T2 relaxation time was derived (R2 = 0.98): T2 (ms) = 30.45 – 1.05 × FP. Thus, these results demonstrate a statistical agreement between T2-map–quantified fibrosis and PSR staining in two different clinically relevant animal models. In conclusion, T2-mapping MRI is a promising noninvasive contrast agent-free quantitative technique to characterize myocardial fibrosis.  相似文献   
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ObjectiveThe overnight rostral fluid shift from the lower limbs is one of the causes of obstructive sleep apnea (OSA). Compression stockings (CS) prevent lower limb fluid retention and have been reported to decrease nighttime fluid shift. The aim of this study is to evaluate the effect of CS on fluid shift and the severity of OSA.MethodsA systematic literature search was performed in the PubMed, EMBASE and Cochrane Library databases. The data were analyzed using Comprehensive Meta-Analysis software (Version 3; Biostat, Englewood, NJ). Studies evaluating the effect of CS on the overnight fluid shift and OSA severity were included in the analysis.ResultsA total of 4 studies were included in this meta-analysis. The pooled analysis showed that the apnea-hypopnea index (AHI) of the overall study group was significantly lower after using CS (SMD, -1.08; 95% CI, -1.49 to -0.67). Decreases in the AHI were also observed in the normal fluid status (SMD, -1.05; 95% CI, -1.73 to -0.37) and fluid overload status (SMD, -1.17; 95% CI, -1.76 to -0.58) populations. The overall study group had significant decreases in overnight changes in neck circumference (SMD, -1.05; 95% CI, -2.06 to -0.03) and leg fluid volume (SMD, -1.14; 95% CI, -1.88 to -0.41) after using CS. However, no significant differences in overnight changes in neck circumference and leg fluid volume were observed in normal fluid status patients.ConclusionCS may help decrease overnight fluid shift and could be a treatment option for OSA.  相似文献   
58.
Bone mineral density (BMD) is a highly heritable predictor of osteoporotic fracture. GWAS have identified hundreds of loci influencing BMD, but few have been functionally analyzed. In this study, we show that SNPs within a BMD locus on chromosome 14q32.32 alter splicing and expression of PAR-1a/microtubule affinity regulating kinase 3 (MARK3), a conserved serine/threonine kinase known to regulate bioenergetics, cell division, and polarity. Mice lacking Mark3 either globally or selectively in osteoblasts have increased bone mass at maturity. RNA profiling from Mark3-deficient osteoblasts suggested changes in the expression of components of the Notch signaling pathway. Mark3-deficient osteoblasts exhibited greater matrix mineralization compared with controls that was accompanied by reduced Jag1/Hes1 expression and diminished downstream JNK signaling. Overexpression of Jag1 in Mark3-deficient osteoblasts both in vitro and in vivo normalized mineralization capacity and bone mass, respectively. Together, these findings reveal a mechanism whereby genetically regulated alterations in Mark3 expression perturb cell signaling in osteoblasts to influence bone mass.  相似文献   
59.
Cervical cancer is a global health challenge in women. Neoadjuvant chemotherapy (NACT) is a recent prospect for alternative cervical cancer treatments. This study investigated the efficacy of NACT against resectable cervical cancer based on the medium and long-term survival of patients with the disease. We searched through PubMed, Web of Science, EBSCO and Cochrane Library for relevant reports published by June 2020. The primary outcomes were 3-year and 5-year progression-free survival (PFS) and overall survival (OS) of patients with resectable cervical cancer. Overall, 22 publications encompassing 5627 patients fulfilled the inclusion criteria. We found NACT not to affect both 3-year PFS and OS as well as 5-year PFS of patients with resectable cervical cancer. However, NACT significantly improves the 5-year OS of patients with resectable cervical cancer (HR = 0.83, 95% CI: 0.73–0.94, p = 0.013). Subgroup analysis (RCTs, non-RCTs, NACT + surgery + AT vs. surgery + AT, NACT + surgery + AT vs. CCRT/RT/CRT) further revealed NACT had no significant effect on 5-year PFS of patients with resectable cervical cancer, converse to the 5-year OS subgroup analysis, which validated the beneficial effect of NACT in patients with resectable cervical cancer. In addition, the effect of NACT was most significant in the non-RCTs subgroup (p = 0.012). NACT may improve the long-term prognosis of patients with resectable cervical cancer. However, further large-scale multicenter studies are needed to validate this finding.  相似文献   
60.
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