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1.
Nat Mater ; 14(7): 675-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25985459

RESUMO

In some materials the competition between superconductivity and magnetism brings about a variety of unique phenomena such as the coexistence of superconductivity and magnetism in heavy-fermion superconductors or spin-triplet supercurrent in ferromagnetic Josephson junctions. Recent observations of spin-charge separation in a lateral spin valve with a superconductor evidence that these remarkable properties are applicable to spintronics, although there are still few works exploring this possibility. Here, we report the experimental observation of the quasiparticle-mediated spin Hall effect in a superconductor, NbN. This compound exhibits the inverse spin Hall (ISH) effect even below the superconducting transition temperature. Surprisingly, the ISH signal increases by more than 2,000 times compared with that in the normal state with a decrease of the injected spin current. The effect disappears when the distance between the voltage probes becomes larger than the charge imbalance length, corroborating that the huge ISH signals measured are mediated by quasiparticles.

2.
Placenta ; 32(5): 367-72, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21435716

RESUMO

Preeclampsia is frequently accompanied by fetal growth restriction (FGR). Preeclampsia increases oxygen free radical production, and the resulting oxidative stress impairs placental blood flow. To determine whether placental oxidative stress is associated with FGR in preeclamptic women, we evaluated placental oxidative DNA damage and its repair in 13 preeclamptic women with FGR, 10 preeclamptic women without FGR, and 11 healthy pregnant women without complications. We measured maternal and umbilical serum derivatives of reactive oxygen metabolites (d-ROMs), as a marker of oxygen free radicals, and pulsatility index (PI) of uterine and umbilical arteries, and performed an immunohistochemical analysis to measure the proportion of nuclei in the placental trophoblast that stained positive for 8-hydroxy-2'-deoxyguanosin (8-OHdG), an indicator of oxidative DNA damage, and redox factor-1 (ref-1), indicative of the repair function towards oxidative DNA damage. D-ROMs were increased in the maternal blood of both preeclamptic groups (with FGR, 687.3 ± 50.4 CARR U, p < 0.01; without FGR, 750.4 ± 87.2 CARR U, p < 0.001) compared with controls (504.7 ± 25.0 CARR U). In contrast, d-ROM levels in the umbilical artery were elevated in preeclamptic women with FGR (134.9 ± 13.3 CARR U, p < 0.01), but not in preeclamptic women without FGR (44.0 ± 7.3 CARR U) compared with controls (38.2 ± 5.0 CARR U). Mean PI for uterine arteries was significantly increased in both preeclamptic groups, and the PI in preeclamptic women with FGR was significantly greater than that in women without FGR (0.94 ± 0.07 vs. 1.31 ± 0.07, p < 0.001). The PI for umbilical arteries was significantly increased in preeclamptic women with FGR (0.90 ± 0.05vs. 1.19 ± 0.07, p < 0.001), but not in preeclamptic women without FGR. The proportion of nuclei positive for 8-OHdG was higher in both groups of preeclamptic women than in the control group, but was higher in preeclamptic women with FGR (0.21 ± 0.05 vs. 0.87 ± 0.01, p < 0.001). The proportion of nuclei positive for ref-1 was higher in preeclamptic women without FGR (0.54 ± 0.06, p < 0.001) than in the control group, whereas the proportion did not differ significantly between normal and preeclamptic women with FGR. Our findings indicate that increased oxidative stress and disrupted compensatory reaction against placental oxidative DNA damage may be associated with FGR in preeclamptic women.


Assuntos
Dano ao DNA , Retardo do Crescimento Fetal/metabolismo , Estresse Oxidativo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Estudos de Casos e Controles , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Feminino , Sangue Fetal/metabolismo , Radicais Livres/sangue , Humanos , Oxigênio/sangue , Gravidez
3.
Nihon Koshu Eisei Zasshi ; 45(2): 151-63, 1998 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-9611995

RESUMO

So-called "negative health behaviors" (e.g. smoking, excessive eating/drinking), which are related to morbidity and mortality, are generally well known to the public. However there are many who undertake negative health behaviors despite knowing of their negative health effects. Using a mail survey of subjects aged 25 to 54, we examined reasons and justifications for engaging in negative health behaviors and their related factors from the lay person's perspective. Concerning the reasons for negative health behaviors, we hypothesized seven concepts (work priority, group harmony priority, the contribution to relaxation, tools for communication, prior orientation focused on the present, individualistic priority, and appearance), and devised multiple questions for each concept. The results are as follows. 1. Compared to females, males tended to support of the five concepts about the internalized norms concerned with negative health behaviors (e.g. the tendency of each individual to approve or disapprove of the reasons for negative health behaviors). In females, the younger generation and those that were married expressed more support than the older and the unmarried. There were differences in males according to occupation. 2. Concerning which reference groups had the largest influence on the social norms concerned with negative health behaviors (e.g. the perceptions as to what degree a group regards the reasons about negative health behaviors as desirable), most perceived that the "office" and "friends" groups would be more supportive of reasons for negative health behaviors than the "family" groups. 3. The health behaviors, which correlated with the internalized norms or the social norms concerned with negative health behaviors, were eating breakfast, smoking, and drinking (frequency and amount). In particular, drinking behavior was influenced most by the internalized norms and the social norms.


Assuntos
Atitude Frente a Saúde , Comportamentos Relacionados com a Saúde , Conformidade Social , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Microsurgery ; 15(10): 726-32, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7885220

RESUMO

In order to understand the mechanisms involved in the hypertrophy of vascularized bone grafts, a series of animal experiments were carried out and 32 clinical cases were studied. A defect in the tibial shaft was created in puppies and the ipsilateral fibula was transferred into the medullary cavity of the tibia with the anterior tibial artery and vein. The same procedure was performed on a control group but without vessel supply. Radiologically, in the vascularized group mild hypertrophy in the fibula was seen at 2 weeks, became marked by 4 weeks, but in no case did the thickening (hypertrophy) of the graft ever exceed the diameter of the recipient tibia. The control group did not show hypertrophy but fracture callus formed in the recipient tibia at both ends of the graft. On histological evaluation no reactive bone formation was evident in the control group but some reactive bone formation was seen in the vascularized group just beneath the periosteum. There was no change in the periosteum itself. In the clinical cases 47% of patients showed hypertrophy. Hypertrophy was noted mainly in the fibulae but rarely in other bones such as ilium or rib. The important factors were age and good vascularity of the grafted bone. During the period of study, weight-bearing was eliminated, so that the effects of mechanical force did not explain hypertrophy. We conclude from these studies that true hypertrophy is an essentially different process from reactive callus which forms normally in response to fracture healing. Vascularized bone grafts show remarkable hypertrophy of the grafted bone, but the exact mechanism is ill defined.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Transplante Ósseo/efeitos adversos , Fíbula/transplante , Hiperostose/etiologia , Adolescente , Adulto , Animais , Transplante Ósseo/diagnóstico por imagem , Transplante Ósseo/patologia , Criança , Cães , Fêmur/cirurgia , Fíbula/patologia , Humanos , Úmero/cirurgia , Hiperostose/diagnóstico por imagem , Hiperostose/patologia , Masculino , Osteomielite/cirurgia , Pseudoartrose/congênito , Pseudoartrose/cirurgia , Radiografia , Tíbia/cirurgia
7.
Microsurgery ; 4(1): 17-22, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6633240

RESUMO

Vascularized grafting with segments of fibula was performed in four men with aseptic necrosis of the femoral head. The patients were restricted to relatively young individuals in whom the necrosis seemed to be confined to two-thirds or less of the femoral head and in whom the outer shell of the femoral head appeared relatively well preserved. The operative technique is described, and the interim results from follow-up ranging from one year, two months to three years, eight months are reported. Three of the four hips became asymptomatic after surgery with x-ray films showing no progression of the necrosis or deformity. In one hip, however, mild pain, bony absorption, and some progression of the deformity persisted. Although the final results in these four cases remain to be seen, vascularized fibular grafting will find a place in the treatment of early avascular necrosis of the femoral head.


Assuntos
Necrose da Cabeça do Fêmur/cirurgia , Fíbula/transplante , Adulto , Cabeça do Fêmur/irrigação sanguínea , Cabeça do Fêmur/diagnóstico por imagem , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Fíbula/irrigação sanguínea , Seguimentos , Humanos , Masculino , Métodos , Pessoa de Meia-Idade , Radiografia
8.
Clin Orthop Relat Res ; (165): 164-7, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-7075054

RESUMO

The work of two Australian surgeons using the same techniques for anterior lumbar interbody fusion operations in 150 patients has been analyzed by an independent observer (A.F.). Used as a primary procedure in 84 cases, only four patients failed to return to work. Time off work varied between 3.3 to 11.8 months, depending on the patients' occupations. Used as a salvage procedure in 38 cases, only five patients failed to return to work. Time off work varied between 24 and 5.6 months depending on the patients' occupations. In 28 cases, supplementary operations were performed following interbody fusions. Even in this difficult group only nine patients failed to return to work.


Assuntos
Vértebras Lombares/cirurgia , Fusão Vertebral , Adulto , Feminino , Humanos , Disco Intervertebral/cirurgia , Masculino , Pessoa de Meia-Idade , Doenças da Coluna Vertebral/cirurgia , Fusão Vertebral/efeitos adversos
10.
Br J Plast Surg ; 30(4): 269-72, 1977 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-338070

RESUMO

Ninety-two anastomoses of arteries 0.5 mm in diameter have been performed in rats with an 85-90 per cent patency rate in the second postoperative week. The factors of prime importance in the achievement of high patency rates have been atraumatic handing and meticulous suturing technique. At 1 hour and at 8 to 10 days the patency rates were not statistically different whether 20 per cent magnesium sulphate heparin or normal saline were used. Similar results were obtained with 40 repairs of divided veins averaging 0.4 mm in diameter. These results suggest strongly that clinical microvascular surgery in vessels approximately 0.5 mm in diameter, especially in children, should given results comparable to 1 mm vessel surgery.


Assuntos
Microcirurgia/métodos , Técnicas de Sutura , Procedimentos Cirúrgicos Vasculares/métodos , Animais , Ratos
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