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971.
972.
Objectives: As of 11 Feb 2020, a total of 1,716 medical staff infected with laboratory-confirmed the severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) in China had been reported. The predominant cause of the infection among medical staff remains unclear. We sought to explore the epidemiological, clinical characteristics and prognosis of infected medical staff.Methods: Medical staff who infected with SARS-Cov-2 and admitted to Union Hospital, Wuhan between 16 Jan to 25 Feb, 2020 were included in this single-centered, retrospective study. Data were compared by occupation and analyzed with the Kaplan-Meier and Cox regression methods.Results: A total of 101 medical staff (32 males and 69 females; median age: 33) were included in this study and 74.3% were nurses. A small proportion of the cohort had contact with specimens (3%) as well as patients infected with SARS-Cov-2 in fever clinics (15%) and isolation wards (3%). 80% of medical staff showed abnormal IL-6 levels and 33% had lymphocytopenia. Chest CT mainly manifested as bilateral (62%), septal/subpleural (77%) and groundglass opacities (48%). The major differences between doctors and nurses manifested in laboratory indicators. As of the last observed date, no patient was transferred to intensive care unit or died. Fever (HR=0.57; 95% CI 0.36-0.90) and IL-6 levels greater than 2.9 pg/ml (HR=0.50; 95% CI 0.30-0.86) were unfavorable factors for discharge.Conclusions: Our findings suggested that the infection of medical staff mainly occurred at the early stages of SARS-CoV-2 epidemic in Wuhan, and only a small proportion of infection had an exact mode. Meanwhile, medical staff infected with COVID-19 have relatively milder symptoms and favorable clinical course than ordinary patients, which may be partly due to their medical expertise, younger age and less underlying diseases. The potential risk factors of fever and IL-6 levels greater than 2.9 pg/ml could help to identify medical staff with poor prognosis at an early stage.  相似文献   
973.
Vγ9Vδ2 T cells are promising candidates for cellular tumor immunotherapy. Due to their HLA-independent mode of action, allogeneic Vγ9Vδ2 T cells can be considered for clinical application. To apply allogeneic Vγ9Vδ2 T cells in adoptive immunotherapy, the methodology used to obtain adequate cell numbers with optimal effector function in vitro needs to be optimized, and clinical safety and efficacy also need to be proven. Therefore, we developed a novel formula to improve the expansion of peripheral γδ T cells from healthy donors. Then, we used a humanized mouse model to validate the therapeutic efficacy of expanded γδ T cells in vivo; furthermore, the expanded γδ T cells were adoptively transferred into late-stage liver and lung cancer patients. We found that the expanded cells possessed significantly improved immune effector functions, including proliferation, differentiation, and cancer cell killing, both in vitro and in the humanized mouse model. Furthermore, a phase I clinical trial in 132 late-stage cancer patients with a total of 414 cell infusions unequivocally validated the clinical safety of allogeneic Vγ9Vδ2 T cells. Among these 132 patients, 8 liver cancer patients and 10 lung cancer patients who received ≥5 cell infusions showed greatly prolonged survival, which preliminarily verified the efficacy of allogeneic Vγ9Vδ2 T-cell therapy. Our clinical studies underscore the safety and efficacy of allogeneic Vγ9Vδ2 T-cell immunotherapy, which will inspire further clinical investigations and eventually benefit cancer patients.  相似文献   
974.
975.
976.
Objectives:To compare the image quality of low-dose CT urography (LD-CTU) using deep learning image reconstruction (DLIR) with conventional CTU (C-CTU) using adaptive statistical iterative reconstruction (ASIR-V).Methods:This was a prospective, single-institutional study using the excretory phase CTU images for analysis. Patients were assigned to the LD-DLIR group (100kV and automatic mA modulation for noise index (NI) of 23) and C-ASIR-V group (100kV and NI of 10) according to the scan protocols in the excretory phase. Two radiologists independently assessed the overall image quality, artifacts, noise and sharpness of urinary tracts. Additionally, the mean CT attenuation, signal-to-noise ratio (SNR) and contrast-to-noise (CNR) in the urinary tracts were evaluated.Results:26 patients each were included in the LD-DLIR group (10 males and 16 females; mean age: 57.23 years, range: 33–76 years) and C-ASIR-V group (14 males and 12 females; mean age: 60 years, range: 33–77 years). LD-DLIR group used a significantly lower effective radiation dose compared with the C-ASIR-V group (2.01 ± 0.44 mSv vs 6.9 ± 1.46 mSv, p < 0.001). LD-DLIR group showed good overall image quality with average score >4 and was similar to that of the C-ASIR-V group. Both groups had adequate and similar attenuation value, SNR and CNR in most segments of urinary tracts.Conclusion:It is feasibility to provide comparable image quality while reducing 71% radiation dose in low-dose CTU with a deep learning image reconstruction algorithm compared to the conventional CTU with ASIR-V.Advances in knowledge:(1) CT urography with deep learning reconstruction algorithm can reduce the radiation dose by 71% while still maintaining image quality.  相似文献   
977.
Objectives:Transcatheter arterial embolisation (TAE) is widely used to treat gastrointestinal bleeding. This paper reports the safety and efficacy of TAE for bleeding following endoscopic resection, including endoscopic mucosal resection and endoscopic submucosal dissection.Methods:Fifteen consecutive patients (13 males, two females; mean age 62.2 years) from two tertiary medical centres who underwent TAE for gastroduodenal bleeding after endoscopic resection from November 2001 to December 2020 were included. Patient demographics, clinical presentations, angiographic findings, and TAE details were retrospectively reviewed.Results:Immediate bleeding during endoscopic resection was noted in four patients. Delayed bleeding 1–30 days after endoscopic resection in nine patients presented with haematochezia (n = 4), haematemesis (n = 6) and melaena (n = 1). Endoscopic haemostasis was attempted in 11 patients (73.3%) but failed due to continued bleeding despite haemostasis (n = 6), failure to secure endoscopic field (n = 3) and unstable vital signs (n = 2). Eleven patients had positive angiographic findings for bleeding, and all bleeding arteries were embolised except one owing to failed superselection of the bleeder. In the other four patients with negative angiographic findings, the left gastric artery with/without the right gastric artery or the accessory left gastric artery was empirically embolised using gelatin sponge particles. Both technical and clinical success rates were 93.3% (14/15). No procedure-related complications occurred during follow-up.Conclusions:TAE is safe and effective in the treatment of immediate and delayed bleeding after endoscopic resection procedures.Advances in knowledge:This is the first and largest 20-year bicentric study published in English on this topic. Empirical TAE for angiographically negative bleeding sites was also effective without significant complications.  相似文献   
978.
979.
Objective:This study investigated the usefulness of quantitative parameters [longitudinal relaxation (T1), transverse relaxation (T2), and proton density (PD)] obtained with synthetic magnetic resonance imaging (MRI) in assessing the progression of temporomandibular joint (TMJ) disorders.Methods:For individual TMJ disorder diagnoses, the presence of disc displacement in MRI and the osseous change in cone-beam CT were investigated. Joints were classified into three stages: (1) silent stage, no disc displacement or osseous change; (2) incipient stage, presence of disc displacement and absence of osseous change; and (3) progressed stage, both disc displacement and osseous change. In synthetic MRI, the T1, T2, and PD values of the condyle bone marrow were measured simultaneously. The median T1, T2, and PD values were analyzed according to disc displacement, osseous changes, and joint stage.Results:Significant differences were observed in the T1 and PD values of joints with disc displacement or condylar osseous change compared to normal joints. The T1 and PD values also differed between the silent and progressed stages. The PD value differed between the silent and incipient groups, while the T2 value did not differ significantly among the three groups.Conclusion:The PD and T1 values of condylar bone marrow obtained from synthetic MRI can be used as sensitive indicators of TMJ disorder progression. The PD value of the bone marrow showed potential as a useful biomarker for recognizing the initial stages of TMJ disorders. Synthetic MRI is useful for the simultaneous acquisition of effective MRI parameters for evaluating TMJ disorders.  相似文献   
980.
International Journal of Legal Medicine - Age estimation based on the analysis of DNA methylation patterns has become a focus of forensic research within the past few years. However, there is...  相似文献   
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