Kazuhide Niiyama

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We reported a 31 year-old man with repeated episodes of migraine at a frequency of about once a week on and after January, 2000. In January 2001, scintillating scotoma and pulsating headache appeared followed by left hemianopsia. His platelet count decreased to 80,000/microliter and high intensity areas were observed in the right occipital lobe and(More)
The nature of the carcinogen present in bracken fern has not yet been elucidated. Very recently, we succeeded in isolating ptaquiloside, a novel norsesquiterpene glucoside of the illudane type, from bracken. Ptaquiloside was shown to be a carcinogenic principle of bracken fern. It induces mammary cancer and multiple ileal tumors in high incidences when(More)
Acute bracken fern toxicity in a calf was reproduced with ptaquiloside, a norsesquiterpene glucoside, isolated from the boiling water extract of bracken fern. Ptaquiloside was dissolved in 500 ml of saline and administered by drench at increasing dosages for six days out of every seven for the following periods: 400 mg/day for 24 days, 800 mg/day for 14(More)
A 57-year-old male with primary intracranial malignant melanoma who survived 9 years and 6 months is reported. He underwent surgical removal of the tumour three times during the decade 1978 to 1988, and received chemo-immuno-radiotherapy during that time. Acute tumour growth, suggesting tumour dissemination, was seen in the CT scans after the third removal(More)
Isolation of the carcinogen in the boiling water extract of bracken fern was conducted by following the active principle with a carcinogenicity bioassay. Fractionation of the bracken extract was carried out using adsorption on resin (Amberlite XAD-2 and TOYOPEARL HW-40 (c] and organic solvent extraction. A diet containing each of the fractions was given to(More)
The effect of dopamine during barbiturate therapy was investigated in 29 cats including 5 sham-operated cats. According to Kiersey's classification of electro-encephalographic patterns, physiological variables, cerebral metabolic rates for oxygen and glucose, cerebral blood flow (CBF), and intracranial pressure (ICP), etc. were evaluated in each(More)
A 52-year-old female presented with localized but severe cerebral vasospasm induced by recurrent aneurysmal subarachnoid hemorrhage. The middle cerebral artery (MCA) aneurysm was clipped and the subarachnoid hematoma evacuated 1 day after recurrent hemorrhage. The cerebral vasospasm, localized in a region near the MCA aneurysm, was reduced by papaverine and(More)
Patients with large metastatic brain tumors are considered to have poor prognosis. We report a case of a patient with more than 33 months survival after complete resection of a huge temporal tumor which had metastasized from a lung cancer. A 57-year-old woman presented left hemiparesis and disturbance of consciousness. Magnetic resonance images revealed a(More)
We present a case of slowly progressive gait ataxia with a 16-year history in an 87-year-old woman. In 1994 she became aware of a slight unsteadiness while walking and cortical cerebellar atrophy was diagnosed. She had no familial history of neurological disorders. In 2007, idiopathic thrombocytopenic purpura (ITP) was diagnosed. The symptoms gradually(More)
We described a dissecting aneurysm of the vertebral artery (VA), which was associated with neurofibromatosis type 1 (NF1). A 41-year-old man was referred to our hospital because of abrupt, severe headache. A CT scan revealed diffuse subarachnoid hemorrhage (SAH) predominantly in the prepontine cistern. The angiograms showed a string sign in the left VA,(More)