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1.
Materials (Basel) ; 15(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36363271

RESUMO

Multifunctional physical properties are usually a consequence of a rich electronic-structural interplay. To advance our understanding in this direction, we reinvestigate the structural properties of the LaPdSb and CePdSb intermetallic compounds using single-crystal neutron and X-ray diffraction. We establish that both compounds can be described by the non-centrosymmetric space group P63mc, where the Pd/Sb planes are puckered and show ionic order rather than ionic disorder as was previously proposed. In particular, at 300 K, the (h, k, 10)-layer contains diffuse scattering features consistent with the Pd/Sb puckered layers. The experimental results are further rationalized within the framework of DFT and DFT+ embedded DMFT methods, which confirm that a puckered structure is energetically more favorable. We also find strong correspondence between puckering strength and band topology. Namely, strong puckering removes the bands and, consequently, the Fermi surface pockets at the M point. In addition, the Pd-d band character is reduced with puckering strength. Thus, these calculations provide further insights into the microscopic origin of the puckering, especially the correspondence between the band's character, Fermi surfaces, and the strength of the puckering.

2.
BJR Case Rep ; 8(1): 20210172, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35136649

RESUMO

In this report, we present a 57-year-old female with a history of mild alcoholic liver disease during a medical check-up. Abdominal computed tomography and magnetic resonance imaging showed a multicystic mass with a solid enhancing mural nodule in the right lobe of the liver. Subsequently, laparoscopic right liver lobectomy was performed and pathological findings revealed intraductal papillary neoplasm of the bile duct (IPNB) with an associated invasive carcinoma. IPNB is a relatively rare disease that should be considered in the differential diagnosis of hepatic cystic tumours. Our case report highlights the importance of capturing image findings of the IPNB as this disease has a high potential for malignancy.

3.
J Phys Condens Matter ; 29(47): 475502, 2017 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-28891807

RESUMO

Electronic structures of ferromagnetic heavy fermion Yb compounds of YbPdSi, YbPdGe, and YbPtGe are studied by photoelectron spectroscopy around the Yb 4d-4f resonance, resonant x-ray emission spectroscopy at the Yb L 3 absorption edge, and density functional theory combined with dynamical mean field theory calculations. These compounds all have a temperature-independent intermediate Yb valence with large [Formula: see text] and small [Formula: see text] components. The magnitude of the Yb valence is evaluated to be YbPtGe [Formula: see text] YbPdGe [Formula: see text] YbPdSi, suggesting that YbPtGe is the closest to the quantum critical point among the three Yb compounds. Our results support the scenario of the coexistence of heavy fermion behavior and ferromagnetic ordering which is described by a magnetically-ordered Kondo lattice where the magnitude of the Kondo effect and the RKKY interaction are comparable.

4.
J Phys Condens Matter ; 27(32): 325601, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26214206

RESUMO

YbPtGe and YbPdGe exhibit ferromagnetic ordering below Tc = 5.4 and 11.4 K with enhanced electronic specific heat coefficients of γ = 209 and 150 mJ K(-2) mol, respectively. In order to shed light on the origin of the coexistence of a ferromagnetic state and heavy-fermion behavior, we studied the powder neutron diffraction of YbPtGe and YbPdGe at low temperatures. Weak reflections due to magnetic ordering have been resolved. The data were analyzed using the Rietveld method together with group theory analysis. It has been found that YbPtGe exhibits a non-collinear ferromagnetic structure, with a spontaneous moment along the c-axis and a weak antiferromagnetic component along the a-axis. The presence of this antiferromagnetic component explains the origin of the observed metamagnetic-like behavior. In the case of YbPdGe, magnetization measurements confirmed the ferromagnetic moment along the b-axis and revealed a metamagnetic transition at 0.2 T for a field parallel to the c-axis. The neutron diffraction results indicate that the magnetic structure of YbPdGe is also of a non-collinear type, with ferromagnetic moments parallel to the b-axis and weak antiferromagnetic components along the c-axis, which is consistent with the magnetization data. A comparison of the results for YbPtGe and YbPdGe has been made. It is suggested that both the Kondo screening effect of ferromagnetic moments and the fluctuation of antiferromagnetic components can contribute to the enhanced mass in the ferromagnetic state.

5.
BMC Med Imaging ; 10: 2, 2010 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-20074342

RESUMO

BACKGROUND: The rupture of gastric varices is associated with high mortality rate. Balloon-occluded retrograde transvenous obliteration (B-RTO), a minimally invasive procedure that was introduced in the mid-1990s, has been widely accepted in Japan. Several reports have indicated that B-RTO yields satisfactory results; however, few reports have discussed the recurrence of gastric varices after this therapy. The purpose of this study is to retrospectively evaluate the technical aspects of B-RTO and the recurrence of gastric varices after treatment with this procedure. METHODS: B-RTO was performed in 47 patients with gastric varices, who were at a risk of variceal ruptures and who may or may not have had a history of variceal bleeding. We injected a sclerosing agent into the gastric varices for 30-60 minutes. To evaluate the therapeutic efficacy of the technique, we obtained contrast-enhanced computed tomography (CT) scans 5 days after B-RTO. As a general rule, if the gastric varices did not appear thrombosed, we repeated the procedure 7 days after the first procedure. RESULTS: B-RTO was a technical success in 37 patients. It was performed once in 26 patients, twice in 6 patients, thrice in 2 patients, and 4 times in 3 patients. Contrast-enhanced CT scans obtained after B-RTO showed thrombosed gastrorenal shunts in 29 patients and patent gastrorenal shunts in 8 patients. The gastric varices recurred in 2 patients who had patent gastrorenal shunts. The overall cumulative relapse-free rate of gastric varices was 90% at 5 years after B-RTO. CONCLUSIONS: B-RTO is an effective treatment modality for gastric varices. Moreover, obliteration of the gastrorenal shunt as well as the gastric varices appears to be important for the treatment of gastric varices.


Assuntos
Varizes Esofágicas e Gástricas/diagnóstico por imagem , Varizes Esofágicas e Gástricas/prevenção & controle , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemorragia Gastrointestinal/prevenção & controle , Derivação Portossistêmica Cirúrgica , Idoso , Oclusão com Balão , Varizes Esofágicas e Gástricas/complicações , Feminino , Hemorragia Gastrointestinal/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevenção Secundária , Estatística como Assunto , Tomografia Computadorizada por Raios X , Resultado do Tratamento
6.
Gan To Kagaku Ryoho ; 35(10): 1691-5, 2008 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-18931570

RESUMO

Ten patients with advanced gallbladder cancer were treated by arterial infusion chemotherapy. Seven patients had unresected tumors, and three had liver metastasis after resection of primary tumor. The infusion catheter-port system was implanted via the femoral artery. 5-fluorouracil, mitomycin C and epirubicin were administered using implantable port. The response rate was 50% and the median survival time was 192 days. In one patient with good PR, a primary tumor was resected, and he survived for 2 years 7 months without recurrence. No severe side effect was found. Systemic chemotherapy using gemcitabine is well accepted, however arterial infusion chemotherapy will be one of the options when systemic chemotherapy is fails.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Vesícula Biliar/tratamento farmacológico , Neoplasias da Vesícula Biliar/patologia , Infusões Intra-Arteriais , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Idoso , Idoso de 80 Anos ou mais , Angiografia , Feminino , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Taxa de Sobrevida , Tomografia Computadorizada por Raios X
7.
Radiat Med ; 24(1): 80-3, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16715667

RESUMO

PURPOSE: For implantation of a catheter-port system for hepatic arterial infusion chemotherapy, catheterization via the femoral artery is occasionally difficult. The purpose of this study was to determine the usefulness of a J-type long sheath, which facilitates difficult trans-femoral catheterization. MATERIALS AND METHODS: We applied this technique to 15 patients for difficult trans-femoral catheterization for catheter-port system placement. RESULTS: We successfully implanted a catheter-port system in all patients using this technique without significant complications. CONCLUSION: We emphasize that our new technique using a J-type long sheath seems to be a reasonable option when trans-femoral catheterization is difficult.


Assuntos
Cateteres de Demora , Artéria Hepática , Infusões Intra-Arteriais/instrumentação , Neoplasias Hepáticas/tratamento farmacológico , Humanos , Radiografia Intervencionista
8.
Gan To Kagaku Ryoho ; 32(7): 1051-3, 2005 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-16044972

RESUMO

A 73-year-old woman with liver metastasis underwent implantation of an infusion catheter-port system for hepatic arterial infusion chemotherapy. She developed multiple infarctions caused by disseminated intravascular coagulation (DIC) due to liver metastases. The hypercoagulability syndrome associated with cancer (known as Trousseau's syndrome) is considered a cause of cerebral infarction. Among the complications of the implantation of an infusion catheter-port system, Trousseau's syndrome may be one of the causes.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Infarto Cerebral/etiologia , Coagulação Intravascular Disseminada/complicações , Bombas de Infusão Implantáveis/efeitos adversos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/tratamento farmacológico , Idoso , Neoplasias Colorretais/patologia , Feminino , Fluoruracila/administração & dosagem , Artéria Hepática , Humanos , Infusões Intra-Arteriais , Leucovorina/administração & dosagem , Neoplasias Hepáticas/secundário
9.
Circ J ; 67(11): 913-7, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14578596

RESUMO

Dipyridamole thallium-201 single-photon emission computed tomography (SPECT) has not been extensively evaluated for risk stratification and the medium- to long-term prognostic value in elderly cardiac patients who are unable to exercise. The present study group comprised 210 consecutive patients aged at least 70 years with known or suspected coronary artery disease (CAD). The SPECT findings were classified as a reversible, fixed, or combined (reversible and fixed) defect. Of the 210 patients, 201 (77+/-5 years, 85 male) were successfully followed for 49+/-26 months. Thirteen (7%) patients had cardiac events: cardiac death (n=10), non-fatal myocardial infarction (n=1), or coronary artery bypass grafting (n=2). Cardiac events occurred in 3 of 112 patients with normal SPECT and in 10 of 89 patients with an abnormal scan (0.7% /year vs 2.8% /year, p=0.01). Stepwise Cox regression analysis revealed that the significant predictors of cardiac events were combined defects (relative risk 7.3) and the number of defect areas (relative risk 4.4). The predictive value of dipyridamole thallium-201 SPECT is maintained over 4 years in mixed populations of elderly CAD patients who are unable to exercise.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Dipiridamol , Coração/diagnóstico por imagem , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único/normas , Idoso , Idoso de 80 Anos ou mais , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Feminino , Humanos , Masculino , Análise Multivariada , Valor Preditivo dos Testes , Prognóstico , Radiografia , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Análise de Sobrevida , Tomografia Computadorizada de Emissão de Fóton Único/métodos
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