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41.
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S Gananadha TDB Yan J Zhao P Clingan D Glenn DL Morris 《Journal of Medical Imaging and Radiation Oncology》2005,49(5):396-399
Hepatic artery infusion (HAI) chemotherapy is associated with higher response rates compared to systemic chemotherapy in those patients with unresectable liver malignancies. Operative hepatic artery catheter (HAC) insertion has significant morbidity and mortality, especially in patients with high‐volume disease, some of whom may not respond to HAI chemotherapy. We report our experience in 45 patients with high‐volume liver disease who were initially treated with HAI chemotherapy via a radiologically placed temporary HAC to try to select the responders who then went on to have an operative HAC. In these 45 patients who had 62 radiologically placed HAC, we found very few major complications, and certainly no complications such as cholecystitis, vascular or malperfusion problems. 相似文献
43.
Vincent J. Major Simon A. Jones Narges Razavian Ashley Bagheri Felicia Mendoza Jay Stadelman Leora I. Horwitz Jonathan Austrian Yindalon Aphinyanaphongs 《Applied clinical informatics》2022,13(3):632
Background We previously developed and validated a predictive model to help clinicians identify hospitalized adults with coronavirus disease 2019 (COVID-19) who may be ready for discharge given their low risk of adverse events. Whether this algorithm can prompt more timely discharge for stable patients in practice is unknown. Objectives The aim of the study is to estimate the effect of displaying risk scores on length of stay (LOS). Methods We integrated model output into the electronic health record (EHR) at four hospitals in one health system by displaying a green/orange/red score indicating low/moderate/high-risk in a patient list column and a larger COVID-19 summary report visible for each patient. Display of the score was pseudo-randomized 1:1 into intervention and control arms using a patient identifier passed to the model execution code. Intervention effect was assessed by comparing LOS between intervention and control groups. Adverse safety outcomes of death, hospice, and re-presentation were tested separately and as a composite indicator. We tracked adoption and sustained use through daily counts of score displays. Results Enrolling 1,010 patients from May 15, 2020 to December 7, 2020, the trial found no detectable difference in LOS. The intervention had no impact on safety indicators of death, hospice or re-presentation after discharge. The scores were displayed consistently throughout the study period but the study lacks a causally linked process measure of provider actions based on the score. Secondary analysis revealed complex dynamics in LOS temporally, by primary symptom, and hospital location. Conclusion An AI-based COVID-19 risk score displayed passively to clinicians during routine care of hospitalized adults with COVID-19 was safe but had no detectable impact on LOS. Health technology challenges such as insufficient adoption, nonuniform use, and provider trust compounded with temporal factors of the COVID-19 pandemic may have contributed to the null result. Trial registration ClinicalTrials.gov identifier: . NCT04570488相似文献
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Kevin E. Fisher Lizmery S. Ferguson Amy M. Coffey Brian Y. Merritt Jonathan L. Curry Andrea N. Marcogliese Angela M. Major Kala Y. Kamdar Dolores H. Lopez-Terrada Choladda V. Curry 《Haematologica》2022,107(8):1880
Programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) are immunomodulatory molecules over-expressed in lymphomas and are promising immunotherapy targets for hematologic malignancies. However, studies of PD-1/PD-L1 overexpression and their clinical significance in aggressive pediatric non-Hodgkin lymphomas (NHL) are limited. We assessed PD-1/PD-L1 overexpression using immunohistochemistry in 68 aggressive pediatric NHL: ALK-positive anaplastic large cell lymphoma (ALK+ ALCL, n=8), Burkitt lymphoma (BL, n=27), and large B-cell lymphoma (LBCL) de novo LBCL, n=22 and diffuse LBCL arising as monomorphic post-transplant lymphoproliferative disorder [PTLD-DLBCL], n=11. In LBCL, correlations between PD-L1 overexpression and Epstein-Barr virus (EBV) status, cell of origin, stage, nodal status, overall survival (OS), and event-free survival (EFS) were examined. The genetic mechanisms of PD-L1 overexpression were investigated using targeted next-generation sequencing (NGS) and cytogenetic data. All ALK+ ALCL samples, 50.0% of de novo LBCL (11/22), 72.7% of PTLD-DLBCL (8/11), and no BL overexpressed PD-L1. Overexpressed PD-L1 correlated with EBV positivity (P=0.033) in LBCL and lower EFS in de novo LBCL (P=0.017). NGS of select LBCL revealed distinct somatic mutations and an ultra-hypermutated PTLD-DLBCL. Most cases with 9p24.1 copy gains overexpressed PD-L1 although some cases had no discernible genetic drivers of PD-L1 overexpression. Overexpressed PD-L1 is common in pediatric LBCL, associated with EBV positivity and 9p24.1 gains, and may have prognostic significance in de novo LBCL. Furthermore, diverse molecular mechanisms for PD-L1 overexpression in aggressive pediatric NHL can occur. Thus, additional studies exploring the therapeutic and prognostic significance and molecular mechanisms of PD-L1 overexpression in aggressive pediatric NHL are warranted. 相似文献
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Eun-Jeung Kang Ofer Prager Svetlana Lublinsky Ana I Oliveira-Ferreira Clemens Reiffurth Sebastian Major Dominik N Müller Alon Friedman Jens P Dreier 《Journal of cerebral blood flow and metabolism》2023,43(2):210
Spreading depolarization (SD) occurs in a plethora of clinical conditions including migraine aura, delayed ischemia after subarachnoid hemorrhage and malignant hemispheric stroke. It describes waves of near-breakdown of ion homeostasis, particularly Na+ homeostasis in brain gray matter. SD induces tone alterations in resistance vessels, causing either hyperperfusion in healthy tissue; or hypoperfusion (inverse hemodynamic response = spreading ischemia) in tissue at risk. Observations from mice with genetic dysfunction of the ATP1A2-encoded α2-isoform of Na+/K+-ATPase (α2NaKA) suggest a mechanistic link between (1) SD, (2) vascular dysfunction, and (3) salt-sensitive hypertension via α2NaKA. Thus, α2NaKA-dysfunctional mice are more susceptible to SD and show a shift toward more inverse hemodynamic responses. α2NaKA-dysfunctional patients suffer from familial hemiplegic migraine type 2, a Mendelian model disease of SD. α2NaKA-dysfunctional mice are also a genetic model of salt-sensitive hypertension. To determine whether SD thresholds and hemodynamic responses are also altered in other genetic models of salt-sensitive hypertension, we examined these variables in stroke-prone spontaneously hypertensive rats (SHRsp). Compared with Wistar Kyoto control rats, we found in SHRsp that electrical SD threshold was significantly reduced, propagation speed was increased, and inverse hemodynamic responses were prolonged. These results may have relevance to both migraine with aura and stroke. 相似文献
47.
目的:观察家兔腓肠肌失神经支配后肌纤维在退行性变与修复性再生过程中超微结构的变化,探讨失神经支配骨骼肌修复性再生障碍的机制。方法:实验于2005-04/2006-04在南方医科大学中心实验室完成。选择成年新西兰大白兔20只,切断一侧胫神经腓肠肌肌支,术后1,4,8,12,16周分别采用耳缘静脉注射空气处死4只。取实验侧和对照侧腓肠肌内侧头肌组织少许,用于制备超薄切片标本,透射电镜观察各时间点兔失神经腓肠肌肌纤维形态。结果:纳入动物20只,均进入结果分析。①正常家兔腓肠肌肌原纤维排列整齐,肌小节和Z线清晰,线粒体均匀分布在肌原纤维之间,排列规则,细胞核位于质膜周边,未见溶酶体。②失神经支配1周,肌原纤维排列基本整齐,线粒体增多,无明显肿胀。③失神经支配4周,线粒体明显增多肿胀,部分线粒体空泡样变,溶酶体增多,Z线模糊,肌原纤维间隙增大。④失神经支配8周,肌纤维明显萎缩退行性变,大部分肌原纤维消失,残留的肌原纤维变得模糊,间隙增大,肌小结丧失正常的结构,胞浆内含有大量空泡变性的细胞器,可发现畸形核,染色质浓缩、边集,肌细胞膜极度皱缩。镜下发现较多的位于基膜下活化的肌卫星细胞,细胞内含有发达的粗面内质网和丰富的胞浆。一些肌卫星细胞直接与肌纤维融合。同时在间质中可发现一些形态上很象成纤维细胞的细胞,不过这些细胞含有大量的粗面内质网,胞浆内有颗粒和微丝,少量的圆形的线粒体。在退行性变的肌纤维基膜下也可发现肌管样结构的再生肌细胞,在这些肌管内一些肌丝在一起聚集成束,没有组装成肌原纤维,没有正常的肌小结结构。在它们周围有细小的空肌管样结构,可能是以往再生的肌细胞退行性变后的残余体。在间质中可发现一些细小的肌纤维。⑤失神经支配12周,大部分肌纤维萎缩退行性变,但是仍可发现没有萎缩的肌纤维,这些肌纤维细胞核位于周边,有良好的收缩系统,纤维排列规则,Z线清晰,有完整的肌膜。⑥失神经支配16周,肌卫星细胞的数量明显减少,并可发现大量细小的肌纤维,多分布在较大的肌纤维附近,肌膜完整平滑,无皱褶。可发现核位于中央的肌纤维,胞浆内肌原纤维结构清楚,但是肌原纤维的排列远不如核位于周边的肌纤维整齐,说明其收缩系统发育不良。结论:失神经支配后肌细胞退行性变和修复性再生同时存在,再生的肌细胞不能,化发育为成熟的肌纤维,进而发生退行性变。长时间失神经支配,肌卫星细胞的耗竭是失神经支配骨骼肌晚期的主要超微结构变化。 相似文献
48.
Major Carl H. Jonas M. C. 《The Psychiatric quarterly》1963,18(4):626-641
Conclusions Homosexuality is no disease entity. It is rather a manifestation of poor personality integration and from the etiological standpoint should be considered in a similar category to excessive masturbation and chronic alcoholism. Homosexuality becomes desirable or necessary as an outlet for libidinous drives in certain individuals, largely because of a combination of adverse psychogenic and environmental forces. These forces have multitudinous ramifications and interrelationships which vary in any individual case. 相似文献
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