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1.
RSC Adv ; 14(24): 17032-17040, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38808236

RESUMO

Nanopore technology, re-fueled by two-dimensional (2D) materials such as graphene and MoS2, controls mass transport by allowing certain species while denying others at the nanoscale and has a wide application range in DNA sequencing, nano-power generation, and others. With their low transmembrane transport resistance and high permeability stemming from their ultrathin nature, crystalline 2D materials do not possess nanoscale holes naturally, thus requiring additional fabrication to create nanopores. Herein, we demonstrate that nanopores exist in amorphous monolayer carbon (AMC) grown at low temperatures. The size and density of nanopores can be tuned by the growth temperature, which was experimentally verified by atomic images and further corroborated by kinetic Monte Carlo simulation. Furthermore, AMC films with varied degrees of disorder (DOD) exhibit tunable transmembrane ionic conductance over two orders of magnitude when serving as nanopore membranes. This work demonstrates the DOD-tuned property in amorphous monolayer carbon and provides a new candidate for modern membrane science and technology.

2.
Neurol Med Chir (Tokyo) ; 31(13): 887-91, 1991 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-1726248

RESUMO

Recurrence of hypertensive intracerebral hemorrhage confirmed by computed tomography scan has rarely been reported. The authors have experienced nine cases of recurrent hemorrhage among 494 cases of hypertensive intracerebral hemorrhage. Recurrence rate was 1.8%. There were eight males and one female with an average age of 60.5 years. Six cases had their first and second attacks in ganglionic regions. Among them, three cases had the second attack in the ipsilateral side, and the other three cases had the second attack in the contralateral side. Two cases had the first attack in the thalamic and the second in the cerebellar regions. One case had the first attack in the pontine and the second in the putaminal regions. Intervals between the first and second attacks were within 6 months for ipsilateral ganglionic attacks and over 4 years for contralateral ganglionic attacks. In all cases systemic blood pressure was normalized or well controlled by antihypertensive agents after the first attack. The mechanism of rebleeding has not been clarified.


Assuntos
Hemorragia Cerebral/epidemiologia , Hipertensão/epidemiologia , Atividades Cotidianas , Fatores Etários , Idoso , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/fisiopatologia , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores Sexuais , Fatores de Tempo , Tomografia Computadorizada por Raios X
3.
No Shinkei Geka ; 19(8): 755-9, 1991 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-1896121

RESUMO

A 57-year-old male was admitted with pulsatile tinnitus and hearing disturbance of the right ear and right peripheral facial palsy. Otological examination revealed a pulsatile red mass in his right ear and right conductive hearing disturbance. CT and MRI showed the mass lesion at his right middle fossa near the geniculate ganglion. Right external carotid angiogram disclosed a tumor stain fed by the middle meningeal artery. The tumor was removed via a combination of subtemporal and transmastoidal approaches. Histologically, this tumor was diagnosed as angiomatous meningioma partly with meningotheliomatous meningioma. Meningioma in this region is very rare. We discussed its clinical and radiological characteristics in comparison with chemodectoma and facial neurinoma at the geniculate ganglion.


Assuntos
Neoplasias dos Nervos Cranianos/cirurgia , Gânglio Geniculado , Meningioma/cirurgia , Angiografia , Neoplasias dos Nervos Cranianos/diagnóstico , Diagnóstico Diferencial , Paralisia Facial/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Meningioma/diagnóstico , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
4.
Jpn J Clin Oncol ; 18(1): 81-4, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2832638

RESUMO

An 18-year-old male patient who had suffered from polyuria, nocturia and easy fatigability since childhood is described. A germ cell tumor in the suprahypophyseal region was diagnosed at the age of 13 years, and was treated by cranial irradiation. Growth retardation and other signs of hypophyseal deficiency successively occurred, and human growth hormone was administered for two years and five months from the age of 16 years until acute lymphoblastic leukemia developed. Adriamycin, vincristine and prednisolone therapy induced complete remission, but the patient died of disseminated intravascular coagulation two months later. The relationship between the occurrence of leukemia and administration of growth hormone is discussed.


Assuntos
Transtornos do Crescimento/etiologia , Hormônio do Crescimento/efeitos adversos , Leucemia Linfoide/etiologia , Radioterapia/efeitos adversos , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/radioterapia , Doxorrubicina/administração & dosagem , Transtornos do Crescimento/tratamento farmacológico , Humanos , Leucemia Linfoide/tratamento farmacológico , Masculino , Neoplasias Embrionárias de Células Germinativas/radioterapia , Prednisolona/administração & dosagem , Vincristina/administração & dosagem
5.
Gan To Kagaku Ryoho ; 12(7): 1423-31, 1985 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-2990350

RESUMO

A total of 71 cases with primary brain tumors (44 cases) and metastatic brain tumors (30 cases) were entered into our clinical studies with MCNU and radiation therapy or MCNU alone. With regard to tumor reduction on CT scan, the response rates obtained for MCNU and radiation were 21.7% for malignant gliomas and 50.0% for metastatic brain tumors. With regard to improvement of neurological signs, the response rates obtained for MCNU and radiation were 62.9% for malignant gliomas and 71.4% for metastatic brain tumors. The response rates for MCNU were 5.8% for malignant gliomas and 46.1% for metastatic brain tumors. In the improvement of performance status, the response rates for MCNU and radiation were 51.8% for malignant gliomas and 64.2% for metastatic brain tumors. The response rates for MCNU were 46.1% for malignant gliomas and 30.7% for metastatic brain tumors. A minimal degree of hematological toxicity occurred but this gradually disappeared. These results suggested that MCNU has relatively effective antitumor activity against metastatic brain tumors and an enhanced effect with radiation against malignant gliomas.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Compostos de Nitrosoureia/uso terapêutico , Antineoplásicos/efeitos adversos , Astrocitoma/tratamento farmacológico , Astrocitoma/radioterapia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Ensaios Clínicos como Assunto , Esquema de Medicação , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Glioma/tratamento farmacológico , Glioma/radioterapia , Humanos , Leucopenia/induzido quimicamente , Compostos de Nitrosoureia/efeitos adversos , Dosagem Radioterapêutica
6.
No Shinkei Geka ; 9(10): 1207-11, 1981 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-7290325

RESUMO

In this paper a case of acute spontaneous subdural hematoma is reported with a review of fifteen cases in the literature. A 48-year-old left handed man suffered from severe headache on a motor cycle but he arrived at his brother's office immediately after. Three hours later he was found unconscious and soon he was brought to our hospital. On admission he was semicomatose with left hemiparesis. There was no evidences of head injury and the x-rays were normal. CT scan disclosed a high density mass in the left temporal extra-axial region with a remarkable shift of midline structures. His bleeding and clotting time were normal. Emergent left craniotomy was performed and a subdural clot without a membrane was evacuated. Neither cortical lacerations nor vascular malformations were seen on the cortical surface. But two spurting cortical arteries with a lateral pin-hole were seen and coagulated. Postoperative angiograms also revealed no vascular anomalies. He discharged one month later and he is now free from any neurological deficits. In the review several characteristic points of acute spontaneous subdural hematoma were discussed.


Assuntos
Hematoma Subdural/cirurgia , Doença Aguda , Hematoma Subdural/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
7.
No To Shinkei ; 31(9): 947-53, 1979 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-508444

RESUMO

Two cases of sphenoethmoidal meningoencephalocele are reported. Patients are a 1 year 7 month old boy and a 3 year old boy. Although sphenoethmoidal meningoencephalocele is reasonably classified as a type of basal meningoencephalocele, the authors could not find out any reports on cases designated as such. The reason must be in difficulty to differentiate the sphenoethmoidal type from the transsphenoidal type. Authors could differentiate them using CT scan. Two other cases were found in cases reported as transsphenoidal type. Further, it is assumed that these four cases including our two cases were accompanied with agenesis of corpus callosum and median cleft lip and palate. Despite the fact that the respective anomalies are rare, they are completely the same, which signifies the possibility that 1) sphenoethmoidal meningoencephalocele, 2) agenesis of corpus callosum and 3) median cleft lip and palate are a single unit of congenital anomalies. It probably should be considered that the cause for these malformations were present even before the formation of the lips which takes place earliest, that is, sixth week of gestation.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Agenesia do Corpo Caloso , Fenda Labial/complicações , Fissura Palatina/complicações , Encefalocele/complicações , Meningocele/complicações , Pré-Escolar , Encefalocele/diagnóstico por imagem , Seio Etmoidal , Humanos , Lactente , Masculino , Meningocele/diagnóstico por imagem , Radiografia , Seio Esfenoidal
11.
No Shinkei Geka ; 4(5): 451-7, 1976 May.
Artigo em Japonês | MEDLINE | ID: mdl-132617

RESUMO

Recent advances in microneurosurgery have markedly improved the result of surgical treatment of aneurysm and arteriovenous malformation in the posterior cranial fossa. However, more precise study on hemodynamics of the vertebro-basilar system may be necessary for further progress in treatment of the vascular lesions. From this point of view, the authors studied the basilar arterial flow of the dog by means of an electromagnetic flow-meter and the flow probe which was specially devised by the authors. (1) The ratio of absolute value of the mean basilar flow to the total brain weight was calculated, and the flow rate was expressed in ml/100 g brain/min. Mean value was 7.1 ml/100 g brain/min under normocapnea. (2) The effect of occlusion of the common carotid, of the external carotid, of the intracranial internal carotid, and of the extracranial internal carotid on the basilar flow was less remarkable in this order. (3) Under normocapnea, occlusion of the unilateral common carotid artery produced 115% increase in the basilar arterial flow. Bilateral common carotid occlusion resulted in 312% increase of the flow, demonstrating a remarkable ability of compensation of the basilar artery through the circle of Willis and leptomeningeal anastomoses. Under hypercapnea, unilateral common carotid occlusion was followed by 81% increase in the basillar flow. Occlusion of both common carotids caused 230% increase in the basilar flow. Percent increase in the basilar flow after unilateral or bilateral common carotid occlusion under normocapnea was significantly larger than under hypercapnea (p less than 0.05 and p less than 0.01 respectively). It may be supposed that under normacapnea the increased basilar flow following bilateral common carotid occlusion may compensate the decrease in total cerebral blood flow due to carotid occlusion. However, the compensatory rise in the basilar flow under hypercapnea may be not enough to supply the dilated vascular bed in the carotid and basilar territories. There might be even a risk of deficiency of blood supply in the territory of the basilar artery, if the vascular resistance in the carotid area could become less than that in the basilar. The significance of CO2 inhalation therapy for ischemic cerebral lesion was discussed. (4) After the both common carotid arteries were occluded, the basilar aretry was clamped temporarily. Following release of basilar occlusion, reactive hyperemia was observed in the basilar flow. Magnitude and duration of the reactive hyperemia increased progressively depending on duration of the basilar occlusion to some extent. The phenomenon may be best explained by a progressive accumulation of vasodilating metabolities in the ischemic area. (5) Unilateral vertebral occlusion caused 37% decrease in the basilar flow. Bilateral vertebral occlusion resulted in reverse of the basilar flow, averaging 61% of the original value in flow rate. (6) Occlusion of the unilateral subclavian artery produced "subclavian steal phenomenon"...


Assuntos
Arteriopatias Oclusivas/fisiopatologia , Artéria Basilar/fisiopatologia , Animais , Artéria Basilar/fisiologia , Dióxido de Carbono/sangue , Doenças das Artérias Carótidas/fisiopatologia , Circulação Colateral , Cães , Fenômenos Eletromagnéticos , Hiperemia/fisiopatologia , Ataque Isquêmico Transitório/fisiopatologia , Pressão Parcial , Fluxo Sanguíneo Regional , Reologia , Síndrome do Roubo Subclávio/fisiopatologia , Artéria Vertebral
12.
No Shinkei Geka ; 4(2): 175-81, 1976 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-943724

RESUMO

Spontaneous regression or disappearance of cerebral arteriovenous malformation (AVM) had been rarely reported in the literatures. Regression after carotid ligation or radiation therapy are not spontaneous one, because these treatments may have some influences on morphological changes of AVM by CBF dynamic change or by some radiobiological effects on AVM. The reported case is 57 aged male. He had an episode of sudden onset of left hemiparesis 7 years ago and was treated conservatively at a private doctor. Afterward he enjoyed his life, for 4 years, he consulted our clinic on account of left hemiconvulsion. Right CAG revealed right parietal AVM (3.5 X 4.0 X 5.O) with dilated feeding and draining vessels. Patient denyed operation at that time, but again consulted our clinic on account of severe left hemiconvulsion. Right CAG was performed again, but right parietal AVM was almost not visualized and feeding and draining vessels were diminished in diameter. Inspite of repeated 4 vessel angiographies AVM was remarkably regressed, and also no angiospastic vessels and intracerebral hematoma were absent in these angiographies. Though spontaneous regression of cerebral AVM is rare course, we report the importance of morphological follow up, when cerebral AVM is nondefinitively treated.


Assuntos
Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Radiografia
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