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1.
Nano Lett ; 19(10): 7119-7123, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31429575

RESUMO

An interface of molecule and metal has attracted much attention in the research field of nanoelectronics because of their high degree of design freedom. Here, we demonstrate an efficient spin-to-charge current conversion at the metal surface covered by a single layer of molecules. Spin currents are injected into an interface between metal (Cu) and lead(II) phthalocyanine by means of the spin pumping method. An observed voltage signal is caused by the inverse Edelstein effect, i.e., spin-to-charge current conversion at the interface. The conversion coefficient, inverse Edelstein length, is estimated to be 0.40 ± 0.06 nm, comparable with the largest Rashba spin splitting of interfaces with heavy metals. Interestingly, the Edelstein length strongly depends on the thickness of the molecule and takes a maximum value when a single layer of molecules is formed on the Cu surface. Comparative analysis between scanning probe microscopy and first-principles calculations reveal that the formation of interface state with Rashba spin splitting causes the inverse Edelstein effect, whose magnitude is sensitive to the adsorption configuration of the molecules.

2.
Phys Rev Lett ; 119(13): 137204, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-29341677

RESUMO

The current-nonlinear Hall effect or second harmonic Hall voltage is widely used as one of the methods for estimating charge-spin conversion efficiency, which is attributed to the magnetization oscillation by spin-orbit torque (SOT). Here, we argue the second harmonic Hall voltage under a large in-plane magnetic field with an in-plane magnetization configuration in magnetic-nonmagnetic topological insulator (TI) heterostructures, Cr_{x}(Bi_{1-y}Sb_{y})_{2-x}Te_{3}/(Bi_{1-y}Sb_{y})_{2}Te_{3}, where it is clearly shown that the large second harmonic voltage is governed not by SOT but mainly by asymmetric magnon scattering without macroscopic magnetization oscillation. Thus, this method does not allow an accurate estimation of charge-spin conversion efficiency in TI. Instead, the SOT contribution is exemplified by current pulse induced nonvolatile magnetization switching, which is realized with a current density of 2.5×10^{10} A m^{-2}, showing its potential as a spintronic material.

3.
Nat Mater ; 10(3): 194-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21336264

RESUMO

The spin transfer torque is essential for electrical magnetization switching. When a magnetic domain wall is driven by an electric current through an adiabatic spin torque, the theory predicts a threshold current even for a perfect wire without any extrinsic pinning. The experimental confirmation of this 'intrinsic pinning', however, has long been missing. Here, we give evidence that this intrinsic pinning determines the threshold, and thus that the adiabatic spin torque dominates the domain wall motion in a perpendicularly magnetized Co/Ni nanowire. The intrinsic nature manifests itself both in the field-independent threshold current and in the presence of its minimum on tuning the wire width. The demonstrated domain wall motion purely due to the adiabatic spin torque will serve to achieve robust operation and low energy consumption in spintronic devices.

4.
Nat Commun ; 11(1): 256, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937762

RESUMO

Magnetic skyrmions, topological solitons characterized by a two-dimensional swirling spin texture, have recently attracted attention as stable particle-like objects. In a three-dimensional system, a skyrmion can extend in the third dimension forming a robust and flexible string structure, whose unique topology and symmetry are anticipated to host nontrivial functional responses. Here we experimentally demonstrate the coherent propagation of spin excitations along skyrmion strings for the chiral-lattice magnet Cu2OSeO3. We find that this propagation is directionally non-reciprocal and the degree of non-reciprocity, as well as group velocity and decay length, are strongly dependent on the character of the excitation modes. These spin excitations can propagate over a distance exceeding 50 µm, demonstrating the excellent long-range ordered nature of the skyrmion-string structure. Our combined experimental and theoretical analyses offer a comprehensive account of the propagation dynamics of skyrmion-string excitations and suggest the possibility of unidirectional information transfer along such topologically protected strings.

5.
Phytochemistry ; 53(2): 311-6, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10680189

RESUMO

To examine the metabolism of proanthocyanidins in banana fruit, (-)-epigallocatechin was treated with the homogenate of the fruit flesh to yield (-)-gallocatechin and an oxidation product, 1-(3,4,5-trihydroxyphenyl)-3-(2,4,6-trihydroxyphenyl)-2-hydroxy-1-propan one. The latter product is a stable form of a key intermediate in the oxidative metabolism of flavan-3-ols, and is also related to the biogenesis of A-type proanthocyanidins. In addition, treatment of the reaction mixture with o-phenylenediamine afforded monomeric and dimeric phenazine derivatives generated by condensation with the o-quinone form of the oxidation product.


Assuntos
Catequina/análogos & derivados , Flavonoides/metabolismo , Frutas/metabolismo , Biotransformação , Flavonoides/química , Estrutura Molecular , Oxirredução , Estereoisomerismo
6.
Clin Neuropathol ; 21(6): 248-51, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12489672

RESUMO

The patient was a 6 year-old girl with a progressive loss of visual acuity. Magnetic resonance imaging showed a suprasellar mass lesion with enhanced gadolinium which was resected. Histopathological study showed a remarkable granulomatous reaction, but a diagnosis was difficult. However, immunohistochemical study showed a few cells that were positive for placental alkaline phosphatase and it was diagnosed as germinoma. Intracranial germinoma with a remarkable granulomatous reaction is rare. However, when germinoma is suspected clinically, an immunohistochemical study is able to identify germinoma even if granulomatous disease is diagnosed histopathologically.


Assuntos
Neoplasias Encefálicas/diagnóstico , Germinoma/diagnóstico , Granuloma/diagnóstico , Fosfatase Alcalina , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Criança , Cisplatino/uso terapêutico , Diagnóstico Diferencial , Etoposídeo/uso terapêutico , Feminino , Proteínas Ligadas por GPI , Germinoma/metabolismo , Germinoma/patologia , Germinoma/radioterapia , Germinoma/cirurgia , Granuloma/metabolismo , Granuloma/patologia , Granuloma/radioterapia , Granuloma/cirurgia , Humanos , Imuno-Histoquímica , Isoenzimas/metabolismo , Imageamento por Ressonância Magnética
7.
J Vet Med Sci ; 56(3): 613-6, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7948408

RESUMO

The effect of sevoflurane-oxygen anesthesia at surgical depth on clinically important features was evaluated in spontaneously breathing cattle given atropine-guaifenesin-thiopental. The mean end-tidal sevoflurane concentrations ranged from 1.4 to 2.0% for 75 min maintenance. Recovery from anesthesia was extremely rapid and smooth. Heart rate increased and arterial pressure was higher during anesthesia, but respiratory rate did not change significantly. Arrhythmia was not observed. Minute ventilation was low due to decreased tidal volume during anesthesia, and changes in blood gases and pH showed mild respiratory acidosis. There were no marked changes in hematologic or serum biochemical values for 7 days postanesthesia. These findings suggest that sevoflurane is an effective inhalant anesthetic showing rapid recovery from anesthesia.


Assuntos
Anestesia Geral/veterinária , Anestésicos , Atropina/administração & dosagem , Éteres , Guaifenesina/administração & dosagem , Éteres Metílicos , Tiopental/administração & dosagem , Anestesia Geral/métodos , Animais , Atropina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Bovinos , Eletrólitos/sangue , Enzimas/sangue , Contagem de Eritrócitos/efeitos dos fármacos , Éteres/farmacologia , Feminino , Guaifenesina/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Hemoglobinas/análise , Contagem de Leucócitos/efeitos dos fármacos , Pré-Medicação , Respiração/efeitos dos fármacos , Sevoflurano , Tiopental/farmacologia , Volume de Ventilação Pulmonar/efeitos dos fármacos , Fatores de Tempo
8.
Rinsho Shinkeigaku ; 35(9): 991-5, 1995 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-8565350

RESUMO

PURPOSE OF THE STUDY: To clarify the clinical effects and the influence of high-dose therapy of gamma-globulin for inflammatory demyelinating peripheral neuropathy, we have investigated changes of serum IgG subclass distribution of the patients with these diseases by this therapy. SUBJECTS AND METHODS: gamma-Globulin (20g/day) was intravenously administrated for 5 days in 4 cases of CIDP, 2 cases of Fisher syndrome and 1 case of Guillain-Barré syndrome. The IgG subclass was measured by sandwich ELISA method four times, namely before the treatment, immediately after, and 2 and 4 weeks after the treatment. RESULTS: Marked symptomatical improvement was observed in all cases. Serum levels of all IgG subclasses were highest just after the therapy, and all subclasses recovered to the pretherapeutic levels in 4 weeks. Attitude of changes in all IgG subclasses of all cases was fairly similar each other. CONCLUSION: These results suggest that high-dose therapy of gamma-globulin is an effective therapy for inflammatory demyelinating peripheral neuropathy with little influences on IgG production and metabolism of IgG.


Assuntos
Doenças Desmielinizantes/terapia , Imunoglobulina G/classificação , Imunoglobulinas Intravenosas/administração & dosagem , Neurite (Inflamação)/terapia , Doenças do Sistema Nervoso Periférico/terapia , Adulto , Idoso , Doenças Desmielinizantes/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Neurite (Inflamação)/imunologia , Doenças do Sistema Nervoso Periférico/imunologia
9.
No To Shinkei ; 41(12): 1245-50, 1989 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-2627543

RESUMO

We reported a case of multiple intracranial tuberculoma associated with miliary tuberculosis and reviewed the cases reported as intracranial tuberculoma in the past 11 years. A 41-year-old diabetic man was admitted to our hospital for the treatment of miliary tuberculosis and respiratory insufficiency. On admissIon, he had no neurological deficits except mild consciousness disturbance due to respiratory failure. He developed headache and mental confusion three weeks after the beginning of antituberculous therapy with isoniazid, streptomycin, rifampicin, and ethambutol. Neurological examination revealed that he had progressive right hemiparesis and was in a confusional state. Enhanced CT showed multiple intracranial nodular lesions. During 6 weeks, he had progressive neurological manifestations in spite of his initial antituberculous treatment. He responded well, however, to the chemotherapy with combination of isoniazid, kanamycin, pyrazinamide and ethionamide that were sensitive to tuberculous bacilli separated from his sputum. He became minimally right-hemiparetic by 6 weeks after the change of antituberculous medication. Serial enhanced CT scan proved to be of great value in the diagnosis and follow-up study of intracranial tuberculoma. From 1978 to 1988, there were 72 reported cases of intracranial tuberculoma in Japan; 37 were male, 32 were female and 3 were uncertain because of no detailed document. The age of onset was distributed from 6 month to 81 years in age and 2 peaks were seen in the second decade and fifth to seventh decade. Thirty-three (48%) out of 69 cases had multiple intracranial lesions. A few reports commented that neurological complications tended to appear even if they were under antituberculous therapy.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Encefalopatias/etiologia , Tuberculoma/etiologia , Tuberculose Miliar/complicações , Tuberculose Pulmonar/complicações , Adulto , Antituberculosos/uso terapêutico , Encefalopatias/diagnóstico por imagem , Encefalopatias/tratamento farmacológico , Quimioterapia Combinada , Humanos , Masculino , Tomografia Computadorizada por Raios X , Tuberculoma/diagnóstico por imagem , Tuberculoma/tratamento farmacológico , Tuberculose Miliar/tratamento farmacológico
10.
Masui ; 47(10): 1217-20, 1998 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-9834594

RESUMO

We investigated the effects of the presence or absence of N2O in propofol anesthesia using a laryngeal mask on the incidence of postoperative sore throat. In the N2O-combined anesthesia group (n = 25), score 0 (no sore throat) was observed in 11 patients; score 1 (slight pain and discomfort that improved on the next day of operation) in 9; and score 2 (persistent pain on the next day) in 5. In the non-N2O-combined anesthesia group (n = 25), score 0 was observed in 21 patients, score 1 in 3; and score 2 in 1, showing a significantly lower incidence of sore throat and milder sore throat than in the N2O-combined anesthesia group. These results suggest that propofol anesthesia using a laryngeal mask not combined with N2O reduces the incidence of postoperative sore throat.


Assuntos
Ar , Anestesia por Inalação , Anestésicos Intravenosos , Máscaras Laríngeas/efeitos adversos , Oxigênio , Faringite/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Propofol , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nitroso/efeitos adversos
11.
Kyobu Geka ; 42(10): 818-21, 1989 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-2796071

RESUMO

A total of ten patients have undergone sequential bypass grafting of the internal mammary artery (IMA) to the coronary arteries at Osaka Medical College. Operative procedures included left IMA bypass to the left anterior descending (LAD) artery and its major diagonal branch in six patients; to the obtuse marginal branch and diagonal branch in three patients; and to the first and the second diagonal branches in one patient. The right internal mammary artery was concomitantly utilized in 4 patients and saphenous vein graft was also utilized in 6 patients. Postoperative angiographic studies were performed in nine patients within 6 months after operation and in all 18 sites of IMA anastomoses, the IMA sequential grafts were patent. Since sequential IMA-coronary bypass technique means the increase of arterial graft, we believe that this technique should be used for multivessel coronary revascularization especially in younger patients.


Assuntos
Anastomose de Artéria Torácica Interna-Coronária/métodos , Adulto , Humanos , Masculino , Pessoa de Meia-Idade
12.
Kyobu Geka ; 50(9): 793-5, 1997 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-9259144

RESUMO

A 70-year-old woman who had a left atrial thrombus without mitral valve disease was reported. On admission her electrocardiogram showed atrial fibrillation, but there was no cardiac murmur. Transthoracic echocardiogram revealed a dilated left atrium and an intact mitral valve, but did not detect any thrombus. Transesophageal echocardiogram, however, demonstrated the thrombus attaching to the left atrial appendage. Removal of the thrombus and maze procedure were performed at the same time. Although a pacemaker (DDDR mode) was required postoperatively, she spends uneventful daily life at two years after the surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias/terapia , Terapia Trombolítica , Trombose/terapia , Idoso , Fibrilação Atrial/cirurgia , Feminino , Fibrinolíticos/administração & dosagem , Átrios do Coração , Doenças das Valvas Cardíacas , Humanos , Valva Mitral , Ticlopidina/administração & dosagem
13.
Gan To Kagaku Ryoho ; 22(11): 1647-51, 1995 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-7574784

RESUMO

Solid tumor treatment was given in our animal laboratory to determine the mechanism of tumor disappearance by direct electric current, and clinical trials were done on 9 far advanced recurrent rectal cancers. Solid tumors of Yoshida sarcoma in Donryu rat were treated by 1 mA of constant direct current for 1 hour a day, for 4 days. The tumors disappeared in 13/16 within 21 days. Positive results of DNA Nick-end labeling and ladder patterns in the gel electrophoresis of DNA were observed in the regressing tumor specimen. It is considered that apoptosis is the one of the mechanisms of a disappearing tumor. As for the clinical trial concern, in 9 cases of rectal cancer, one CR and 5 PR were seen.


Assuntos
Terapia por Estimulação Elétrica , Recidiva Local de Neoplasia/terapia , Neoplasias Retais/terapia , Sarcoma de Yoshida/terapia , Idoso , Animais , Apoptose , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ratos , Sarcoma de Yoshida/patologia
14.
Nihon Shokakibyo Gakkai Zasshi ; 93(5): 312-21, 1996 May.
Artigo em Japonês | MEDLINE | ID: mdl-8642768

RESUMO

We studied ten cases with abdominal pain after eating raw firefly squid, Watasenia scintillans, Hotaruika. Characteristic clinical features were abdominal pain, nausea, vomiting, diarrhea, creeping eruption and ileus with ascites. In ten patients, there were all cases with abdominal pain, nine with nausea and vomiting, four with diarrhea, one with creeping eruption, six with ileus. Laboratory examination revealed eosinophilia on peripheral blood in ten cases and high serum IgE value in nine cases. The infection rate of type X lavae of the suborder spirurina in Watasenia scintillans is almost 3%, so we measured the antibody to type X larvae of the suborder spirurina in nine patients by indirect fluorescent antibody method and the antibody titer was positive in seven cases. Most patients recovered in several days from first visit. But one patient was diagnosed peritonitis and operated with partial ileectomy. Pathological finding of resected specimen showed an erosion in the mucosal layer and an inflammation with marked eosinophilia in the submucosal layer. These results suggest that abdominal complaints after eating Watasenia scintillans are due to type X larvae of the suborder spirurina.


Assuntos
Abdome Agudo/etiologia , Decapodiformes/parasitologia , Doenças Transmitidas por Alimentos/parasitologia , Frutos do Mar/parasitologia , Infecções por Spirurida , Spirurina , Adulto , Animais , Feminino , Doenças Transmitidas por Alimentos/complicações , Humanos , Masculino , Pessoa de Meia-Idade
15.
Rinsho Hoshasen ; 34(5): 525-31, 1989 May.
Artigo em Japonês | MEDLINE | ID: mdl-2746951

RESUMO

131 colorectal cancers, less than 3 cm in diameter, experienced at Juntendo University Hospital in Oct. 1977 through Dec. 1988 were studied with respect to their radiological and macroscopic features. Macroscopic features of the cancers were classified into type a (a lesion with a long stalk), type b (a subpedunculated or sessile lesion), type c (a plaque-like lesion) and type d (a lesion with a depression). Type a is early cancer. An early cancer of type b was mostly demonstrated as a lobular pattern of tumor surface, and an advanced cancer as a nodular pattern. Type c less than 1 cm in diameter was seen a sm cancer. A sm cancer of type d was mostly demonstrated as a faint barium fleck of the depression, an advanced cancer as a mild barium fleck. By deformed colonic wall in profile view, an early cancer was mostly demonstrated as a thorn shape deformity, sm or pm cancer as an arch shaped deformity and a cancer with deeper cancerous invasion than pm as a trapezoid deformity.


Assuntos
Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/patologia , Humanos , Invasividade Neoplásica , Estadiamento de Neoplasias , Radiografia
18.
Gan No Rinsho ; 34(4): 427-30, 1988 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-3357258

RESUMO

From April, 1982 to March, 1987, we have performed 36,566 gastrofiberscopic examinations and have detected 793 gastric cancers among 7,618 biopsies. Of these 55 cancerous lesion (6.9%) diagnosed as benign at the time of endoscopic examinations were analyzed and the following results were noted. 1. Most such lesions were small in size and superficial in nature. 2. The gross appearances of the cancers were mainly IIc, IIc + III or IIa. 3. The lesions were most frequently located on the gastric angulus or the side with a lesser curvature. 4. Histologically, well differentiated adenocarcinomas were relatively frequent. 5. False-negative cases determined by endoscopic examination were not infrequent in cases of lesions involving an ulcer, or showed redness, erosion or a polyp.


Assuntos
Gastroscopia , Neoplasias Gástricas/patologia , Estômago/patologia , Diagnóstico Diferencial , Reações Falso-Negativas , Gastrite/patologia , Humanos , Pólipos/patologia , Úlcera Gástrica/patologia
19.
ASAIO Trans ; 36(3): M199-202, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2123633

RESUMO

Targeting chemotherapy to the metastatic lesions of the lymph nodes after surgical removal of the main tumor, a drug delivery system using ultrafine particles of activated charcoal was developed and examined for its ability to adsorb mitomycin C (MMC) and to transport MMC to the lymph system. Satisfactory results were obtained. In animal experiments, serial sampling of thoracic duct lymph by cannulation and serial samplings of peripheral vein blood after injection of MMC-charcoal solution into the subserosal space of the intestinal wall were made to study the pharmacodynamics of the lymph-blood system through analysis of MMC regression curves. Clearance (K) and half-life (t1/2) are calculated from the formula; C(t) = C(t0) X e-kt, and compared with that of MMC-saline. Activated charcoal has a proven ability to transport MMC to the lymphatic system. With activated charcoal, MMC is retained for much longer in the lymph nodes than with saline. Congestion of the lymph system was produced by ligation of the thoracic duct in CH-40, with 25% prolongation of t1/2. In conclusion, these drug delivery systems are suitable for targeting chemotherapy at lymph node metastases, and it is proven that 1500 AA Mitsubishi ultrafine charcoal is a good carrier of drug and a slow drug-release material in the lymphatics. Minimal side effects are expected because of the constant low concentrations in the general circulation.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Metástase Linfática/fisiopatologia , Mitomicinas/administração & dosagem , Animais , Carvão Vegetal , Neoplasias Colorretais/metabolismo , Cães , Linfa/química , Mitomicina , Mitomicinas/farmacocinética , Tamanho da Partícula , Veículos Farmacêuticos
20.
Shigaku ; 78(3): 593-8, 1990 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-2134806

RESUMO

The term "esthetics" has recently been also used in the dental field, and a field called esthetic dentistry is increasingly being noted. The number of not only adult but also pediatric patients who visit for treatment aiming at esthetic recovery is being increased. Inpedodontics, composite resin of the coronal color is generally used in the restoration of deciduous incisors. However, the method using metal crowns for the deciduous teeth is used for the deciduous molars at present. We applied a composite resin jacket crown to the deciduous molar in a way similar to that of esthetic crown restoration for the anterior teeth. The surgical procedure before crown preparation varied slightly according to the presence or absence of pulpal treatment of vital teeth and with non-vital teeth, but the application was performed as follows: 1) Desensitization of pulp, pulpal treatment and core construction. 2) Preparation of crown. 3) Selection, trial set and occlusal equilibration of a metal crown for the deciduous tooth. 4) Precision impression with a silicone impression material. 5) Removal of the metal crown for the deciduous tooth from the impression material. 6) Making of an under-cut to the abutment tooth on the buccal lingual side. 7) Filling of the impression with chemical polymerization resin. 8) Application of pressure in the oral cavity. 9) Adjustment of edge and crown forms. Thus, the preparation method for the composite resin jacket crown was relatively simple. Since this surgery, the patient has been followed up for 1 year and 6 months, and no specifically troublesome points have been observed clinically. The patient and her parents are satisfied with the results.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Resinas Compostas , Coroas , Dente Molar , Dente Decíduo , Criança , Pré-Escolar , Estética Dentária , Feminino , Humanos
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