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51.
Nobuyasu Awano Nene Oyama Keiko Akiyama Minoru Inomata Naoyuki Kuse Mari Tone Kohei Takada Yutaka Muto Kazushi Fujimoto Yu Akagi Momoko Mawatari Akihiro Ueda Junko Kawakami Junko Komatsu Takehiro Izumo 《Internal medicine (Tokyo, Japan)》2020,59(21):2693
Objective Coronavirus disease 2019 (COVID-19) is spreading around the world. The aim of this study was to assess the degree of anxiety, depression, resilience, and other psychiatric symptoms among healthcare workers in Japan during the COVID-19 pandemic. Methods This survey involved medical healthcare workers at the Japanese Red Cross Medical Center (Tokyo, Japan) between April 22 and May 15, 2020. The degree of symptoms of anxiety, depression, and resilience was assessed using the Japanese versions of the 7-item Generalized Anxiety Disorder Scale (GAD-7), Center for Epidemiologic Studies Depression Scale (CES-D), and 10-item Connor-Davidson Resilience Scale. Furthermore, we added original questionnaires comprising three factors: (i) anxiety and fear of infection and death; (ii) isolation and unreasonable treatment; and (iii) motivation and escape behavior at work. Results In total, 848 healthcare workers participated in this survey: 104 doctors, 461 nurses, 184 other co-medical staff, and 99 office workers. Among all participants, 85 (10.0%) developed moderate-to-severe anxiety disorder, and 237 (27.9%) developed depression. Problems with anxiety and fear of infection and death, isolation and unreasonable treatment, and motivation and escape from work were higher in the depression group than in the non-depression group (total CES-D score ≥ 16 points). Being a nurse and high total GAD-7 scores were risk factors of depression. Older workers and those with higher resilience were less likely to develop depression than others. Conclusion During the COVID-19 epidemic, many healthcare workers suffered from psychiatric symptoms. Psychological support and interventions for protecting the mental health of them are needed. 相似文献
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54.
Ying-Bo Lu Shinji Kanehashi Kazushi Minegishi Shu-Ping Wang Jin Cheng Kenji Ogino Shijun Li 《RSC advances》2021,11(53):33431
Triphenylamine derivates have been utilized as building blocks in hole-transporting materials. Herein, we describe the synthesis of three octyl-derived conjugated triphenylamine macrocycles with different sizes, and a 4-(2-ethylhexyloxy)-substituted cyclic triphenylamine hexamer using a palladium-catalyzed C–N coupling reaction. These conjugated triphenylamine macrocycles not only have interesting structures, but also are capable of complexing with C60, C70 and PC61BM. Their binding stoichiometries with fullerenes were all determined to be 1 : 1 by an emission titration method. The association constants of these complexes were measured to be in the range of 0.115–1.53 × 105 M−1 depending on the cavity size of the triphenylamine macrocycles and the volume of the fullerenes. The space-charge-limited current properties of the complexes were further investigated using the fabricated ITO/PEDOT:PSS/active layer/Au devices.Cyclic triphenylamine (TPA) oligomers synthesized by C–N coupling were found to be capable of complexing with fullerenes, and the applications in optoelectronic devices were investigated by using the fabricated ITO/PEDOT:PSS/active layer/Au devices. 相似文献
55.
Optical properties of semiconductor quantum dots (QDs) can be tuned by doping with transition metal ions. In this study, water-soluble CdSe/ZnS:Mn/ZnS QDs with the core/shell/shell structure were synthesized through a hydrothermal method, in which the surface of the CdSe core was coated with a ZnS:Mn shell and ZnS capping shell. Herein, the CdSe core QDs were prepared first and then doped with Mn2+; therefore, the QD size and doping level could be controlled independently and interference from the self-purifying effect could be avoided. When CdSe cores with diameters less than 1.9 nm were used, Mn-related photoluminescence (PL) was observed as the main PL band, whereas the band-edge PL was mainly observed when larger CdSe cores were used. Furthermore, using ZnS:Cu as the doping shell layer, CdSe/ZnS:Cu/ZnS and ZnSe/ZnS:Cu/ZnS nanoparticles were successfully synthesized, and Cu-related PL was clearly observed. These results indicate that the core/shell/shell QD structure with doping in the shell layer is a versatile method for synthesizing doped QDs.The core/shell/shell QD structure with doping in the shell layer is a versatile method for synthesizing doped QDs. 相似文献
56.
D'Onofrio M Barbi E Dietrich CF Kitano M Numata K Sofuni A Principe F Gallotti A Zamboni GA Mucelli RP 《European journal of radiology》2012,81(4):630-638
Aim
To describe the typical CEUS pattern of pancreatic lesions and to evaluate the diagnostic accuracy of Contrast-enhanced ultrasound (CEUS) in their characterization.Materials and methods
All US and CEUS examinations of focal pancreatic masses performed in six centers during a period of five years were reviewed. Inclusion criteria were: focal pancreatic mass pathologically proved, visible at ultrasound (US) and studied with CEUS. All lesions were then evaluated for size, aspect and enhancement pattern. Sensitivity, specificity, positive and negative predictive values with 95% CIs were calculated to define diagnostic accuracy of CEUS in respect to pathology. Diagnostic confidence of US and CEUS, discerning between benign and malignant lesions, were represented by using ROC (receiver operating characteristics) curves. Agreement was evaluated by means of k statistics.Results
1439 pancreatic lesions were included. At CEUS the lesions were divided into solid (89%) and cystic (12%) masses and classified into six and eight categories, respectively. Among the solid lesions, adenocarcinomas were characterized with an accuracy of 87.8%. Among the cystic lesions, cystic tumors were diagnosed with an accuracy of 97.1%. ROC curve area increased from 0.637 for US to 0.877 for CEUS (p < 0.0001). Inter-observer agreement was slightly higher for solid (k = 0.78) than cystic (k = 0.62) lesions. In none of the centers side effects were reported.Conclusion
CEUS is accurate in the characterization of pancreatic lesions. CEUS should be considered as a complementary imaging method for pancreatic lesions characterization. 相似文献57.
Merits and Demerits of Operative Procedure to the Trachea in Patients with Differentiated Thyroid Cancer 总被引:3,自引:1,他引:3
Nakao K Kurozumi K Fukushima S Nakahara M Tsujimoto M Nishida T 《World journal of surgery》2001,25(6):723-727
Local radical thyroidectomy, including cervical lymph node dissection and combined circumferential resection of the trachea,
has been performed over the past 20 years in 31 patients with differentiated cancer invading the trachea. The 5- and 10-year
survival rates for these patients were 77.4% and 66.7%, respectively. In 19 of the 31 (61%) cases the recurrent nerve was
resected because of direct cancer invasion. Bilateral recurrent nerve palsy occurred in 12 patients, 3 of whom were managed
postoperatively using a T-shaped tube for preservation of the larynx. Hoarseness remained in 21 patients. In two patients
with recurrent cancer invasion of the larynx, partial laryngectomy and hemilaryngectomy were performed, and reconstruction
was done using ear cartilage without postoperative dyspnea or dysphagia. Parathyroid function is an important factor in regard
to the quality of life of patients. In 22 patients at least one of the parathyroids was preserved. Postoperative calcium administration
was necessary in 14 patients. Our long-term observations indicate that local radical thyroidectomy with combined resection
of the trachea can serve as a useful treatment for advanced differentiated cancer invading the airway. 相似文献
58.
Shigeru Saito Shinji Tanaka Yoshitaka Hiroe Yusuke Miyashita Saeko Takahashi Kazushi Tanaka Shutaro Satake 《Catheterization and cardiovascular interventions》2003,59(1):26-33
Transradial coronary intervention (TRI) can be performed in elective patients with low incidence of access site complications. However, the feasibility of primary stent implantation by TRI is still not clear in patients with acute myocardial infarction (AMI). We prospectively randomized 149 patients out of 213 patients with AMI within 12 hr from onset into two groups: 77 patients treated by TRI (TRI group) and 72 patients by transfemoral coronary intervention (TFI; TFI group). We compared the incidences of major adverse cardiac events (MACE; repeat MI, target lesion revascularization, and cardiac death) during the initial hospitalization and 9-month follow-up periods in both groups. There were one patient who crossed over to the opposite arm, and two patients with severe bleeding complications in the TFI group. Background characteristics of patients were similar between the two groups. The success rate of reperfusion and the incidence of in-hospital MACE were similar in both groups (96.1% and 5.2% vs. 97.1% and 8.3% in TRI and TFI groups, respectively). In selected patients with AMI, primary stent implantation by TRI is feasible as compared to TFI. 相似文献
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