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11.
We have developed an implant heating system (IHS) for interstitial hyperthermia of brain tumors. IHS consists of three compartments: ferromagnetic implant with low Curie point, induction coil and generator to produce high frequency magnetic field. The device works as follows: It is heated up to a Curie temperature (Tc) by Eddy current under the magnetic field. Heat generated in the implant is conducted to the tumor tissue into which it has been implanted. To evaluate the effect of this hyperthermia, a brain tumor model was produced by innoculation of VX2 tumor cells and treated either by hyperthermia with IHS alone, chemotherapy with ACNU alone, or with a combination of both. The longest survival was obtained by the combined treatment, and significant prolongation of survival was found in the single treatment groups. In the Phase I clinical trial, one or several implants (1.8 mm X 15 mm, Tc = 68 degrees C) made of Fe-Pt alloy were placed in the tumor by CT guided stereotactic procedure, or manually during craniotomy. Hyperthermia of above 42 degrees C for 30 to 60 minutes twice a week was brought about in ten cases of malignant brain tumor. CT evaluation was made in nine cases treated for more than ten times in this way. Five out of the nine cases responded to this hyperthermia with irradiation. In conclusion, a safe, repeated and longterm treatment was possible without significant side effects. The hyperthermia with IHS may also be applicable to benign intracranial tumors and neoplasms in other part of body as well.  相似文献   
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Abstract. Paraformaldehyde-fixed platelets from normal donors were used for detection of antibody to platelet by in vitro sensitization (indirect method) utilizing rabbit anti-human IgG heavy chain specific antibody-coated polyacrylamide gels (Immunobeads). The sensitized platelets formed rosettes with Immunobeads and the positive rosette count was over 30%, while control showed less than 8% when normal sera were used. This method was also applicable for detecting antibody-sensitized platelets in vivo (direct method) in patients with autoimmune thrombocytopenia. This method is simple, rapid and reproducible for clinical use. Direct and indirect immunofluorescent antibody tests and a blocking test with anti-human serum also supported the results of Immunobead rosetting technique.  相似文献   
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Morning blood pressure is reported to be more closely related to hypertensive organ damages such as left ventricular mass index, microalbuminuria and silent cerebral infarcts, than blood pressure at other times of the day. Morning blood pressure may play an important role in the pathogenesis of hypertensive target organ damage. Increased sympathetic nerve activity is reported to be one of the mechanisms of morning hypertension; however, there are no available data that show whether strict home blood pressure control, especially in the morning period, can reduce target organ damage. The Japan Morning Surge-1 (JMS-1) study includes hypertensive outpatients with elevated morning systolic blood pressure (>or=135 mmHg) as assessed by self-measured blood pressure monitoring at home. All enrolled patients are under stable antihypertensive medication status. Exclusion criteria are arrhythmia, chronic inflammatory disease, and taking alpha-blockers or beta-blockers. The target number of patients to be enrolled in the JMS-1 study is 600, and the aim is to evaluate differences in the markers of hypertensive target organ damage, such as brain natriuretic peptide and the urinary albumin excretion/creatinine ratio. All of the patients are randomized to an experimental group or a control group, with randomization to be carried out by telephone interviews with the patients' physicians. In the experimental group, patients begin taking additional antihypertensive medication just before going to bed. This consists of doxazosin 1 mg/day, which then is increased to 2 mg/day and 4 mg/day, with a beta-blocker added after a 1-month interval until the morning systolic blood pressure is controlled to less than 135 mmHg. Patients in the control group continue the treatment they are receiving at the enrollment for 6 months. Blood pressure levels, adverse effects, and hypertensive target organ damage before and after the study are evaluated. In the JMS-1 study, we will evaluate whether strict morning blood pressure control by sympathetic nervous system blockade using an alpha-blocker, doxazosin, and with the addition of a beta-blocker if needed, can reduce hypertensive target organ damage.  相似文献   
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We reported a case of X-linked lymphoproliferative syndrome (XLP) with multiple nodular lesions in the brain and lungs. A 21-year-old man was admitted because of one month history of low grade fever, headache, nausea, and amnesia. He developed agammaglobulinemia following Epstein-Barr virus infection at 3-year-old, and thereafter was administered 7.5g of immunoglobulin every 3 weeks with a diagnosis of XLP. Physical examination was unremarkable on admission. Neurological examination revealed disorientation of time, and bilateral gaze-evoked nystagmus. Neuropsychological tests demonstrated impairment of recent memory and calculation. Pleocytosis (83/microl) and increase of protein (1269 mg/dl) and IgG (141 mg/dl) in the CSF were observed. Brain MRI showed multiple nodular lesions with high intense signal on T2-weighted images and Gd-DTPA enhancement on T1-weighted images. Chest CT showed multiple nodular lesions in the bilateral lungs. The needle lung biopsy was performed, which showed infiltration of lymphocytes around the vessels. An immunohistochemical study showed that the infiltrating cells were mainly CD8 positive T lymphocytes. B lymphocyte and plasma cells were not seen. The histological findings excluded intravascular malignant lymphoma and lymphomatoid granulomatosis. Therefore we diagnosed lymphoid vasculitis. The patient developed pancytopenia caused by hemophagocytic syndrome 48 days after admission and was treated with 1 g of methylprednisolone per day for 3 days and a tapered dose of steroid (500 mg to 125 mg of methylprednisolone and 60 mg to 10mg of predonisolone) for 21 days, which resulted in the improvement of clinical features (hemophagocytic syndrome and central nervous system symptoms) and the abnormal CSF findings. The multple nodular lesions in the brain and the lungs shrank 1 month after treatment and disappeared 11 months later. There are few reports concerning lymphoid vasculitis with XLP, and no effective treatment has been described. Our case suggests that steroid therapy may be useful for the treatment of lymphoid vasculitis in XLP.  相似文献   
17.
Abstract Several lines of evidence implicate protein kinase C (PKC) in the development of basal cell and squamous cell carcinomas, tumors which originate from epidermal keratinocytes. To examine PKC in a model relevant to human skin, we exposed normal human epidermal keratinocytes (NHEK) in serum-free media to a variety of PKC agonists and antagonists. NHEK PKC activity increased up to 10-fold within the 1st hour of exposure to tetradecanoyl phorbol acetate (TPA), and gradually returned to control values within 72 h. TPA-induced PKC activity was enhanced by pretreatment of cultures with protein and RNA synthesis inhibitors. TPA-induced growth arrest and differentiation was antagonized by staurosporine. Down-regulation by bryostatin pretreatment blocked TPA-stimulated differentiation. Our overall conclusion is that activation of PKC in cultured human keratinocytes is required for differentiation. These results are crucial to the analysis of compounds suspected of promoting or inhibiting epidermal tumors.  相似文献   
18.
A 56-year-old man was admitted to our hospital with right chest pain. Chest X-ray, CT scan and MRI revealed a chest wall tumor and enlarged mediastinal lymph nodes. Percutaneous lung biopsy was performed, and the pathological diagnosis of pleomorphic rhabdomyosarcoma was obtained. The only significant abnormal laboratory finding was elevation of serum NSE (24.5 ng/ml). Although chemotherapy (VAC-ADM) and radiation therapy were performed, the patient died about 7 months after admission. To our knowledge, only 17 cases of chest wall rhabdomyosarcoma have been reported in Japan.  相似文献   
19.
Clinical features of 16 patients with mild systemic lupus erythematosus (SLE) were compared with those of 21 control patients with moderate or severe disease. Age at the time of diagnosis of SLE was higher in mild disease group. The incidence of the coexistence of Sj?gren's syndrome (SS) at the time of diagnosis of SLE was higher in patients who later developed mild disease. Anti-Sm antibody and decreased levels of C3, C4, and CH50 occurred less frequently in patients with mild disease. SLE patients with the coexistence of SS at the time of diagnosis of SLE may represent a subset with a benign prognosis.  相似文献   
20.
The purpose of this study was to determine the relationship between segmental hyperintensity of the liver on T1-weighted images and segmental cholestasis in patients with obstructive jaundice. T1-weighted and T2-weighted MR images were obtained of 73 patients with obstructive jaundice caused by various diseases. Fat-suppressed T1-weighted images were also obtained of 10 patients. Eleven patients with segmental intra-hepatic bile duct dilatation (cholestasis) showed segmental hyperintensity on T1-weighted images and/or fat-suppressed T1-weighted images and no signal intensity difference on T2-weighted images. Sixty-two patients with widespread intrahepatic bile duct dilatation showed no intensity difference on T1-weighted and T2-weighted images (P < .01). Segmental hyperintensity on T1-weighted images was correlated with intrahepatic cholestasis.  相似文献   
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