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81.
Degeneration of the stria vascularis (SV) is amongst the major causes of cisplatin (CDDP)-induced hearing impairment. The pathways of apoptosis occurring in the SV due to CDDP were examined using a mouse experimental model. Temporal bones of adult C57BL/6 mice were collected on days 3, 7 and 14 after the local application of CDDP. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay and immunostaining for apoptosis-related proteins or reactive radical species were employed for analysis. Local application of CDDP caused apoptotic cell death of marginal cells 3 days after CDDP treatment. Immunohistochemical analyses demonstrated activation of caspase-3 and -9, but not -8, and redistribution of cytochrome c in affected marginal cells, indicating a caspase-dependent, mitochondrion-mediated apoptotic pathway in marginal cells. Temporary expression of hydroxynonenal, nitrotyrosine and inducible nitric oxide synthase in the SV was observed at the induction of apoptosis in marginal cells. CDDP toxicity generates reactive radical species in the SV, which causes mitochondrial membrane permeabilization leading to apoptosis of marginal cells.  相似文献   
82.
The authors describe the clinical features of Creutzfeldt-Jakob disease (CJD) with the causative point mutation at codon 180. The symptoms never started with visual or cerebellar involvement. The patients showed slower progression of the disease compared with sporadic CJD. They never showed periodic sharp and wave complexes in EEG. MRI demonstrated remarkable high-intensity areas with swelling in the cerebral cortex except for the medial occipital and cerebellar cortices. These characteristic MRI findings are an important clue for an accurate premortem diagnosis.  相似文献   
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84.
Epithelioid hemangioendothelioma is an extremely rare, difficult-to-diagnose vascular tumor mainly originating from the lung or liver. Primary tumors in the head and neck are very rare. A 40-year-old man admitted for right throat pain had been found in biopsy elsewhere to have squamous cell carcinoma. Based on a diagnosis of mesopharyngeal cancer, he underwent radical surgery, reporting cough, sputum, and hemosputum postoperatively. Epithelioid hemangioendothelioma was first diagnosed histopathologically from a biopsy of scalp tumors. Lung specimens at open biopsy 4 years earlier showed the same histological features indicating he had had epithelioid hemangioendothelioma lesion since that time. We assumed this epithelioid hemangioendothelioma had originated in the lung and metastasized to the right tonsil. These tumors are typically progressive and aggressive, and this patient had a poor prognosis. We discuss tumor features and review them clinically and histologically.  相似文献   
85.
The adult retina is organized into three cellular layers--an outer photoreceptor, a middle interneuron and an inner retinal ganglion cell (RGC) layer. Although the retinal pigment epithelium (RPE) and Müller cells are important in the establishment and maintenance of this organization, the signals involved are unknown. Here we show that Sonic hedgehog signaling from RGCs is required for the normal laminar organization in the vertebrate retina.  相似文献   
86.
87.
Familial occurrence of inclusion body myositis is extremely rare, and only a few cases in Western countries have been reported. In these reports, a strong association of this disease with DR3 (DRB1*0301/0302) and the efficacy of immunosuppressants suggested that an immune pathomechanism is involved in the disease. We, for the first time, report two Japanese sisters who suffered myopathy clinicopathologically similar to inclusion body myositis. One sister received corticosteroid and azathioprine and the therapy relieved dysphagia. Both of our patients had DR15(2)/4 (DRB1*1502/0405), suggesting a distinct genetic association with the disease in the Japanese population.  相似文献   
88.
Eighty-one adult patients with bronchial asthma who suffered from an unstable peak expiratory flow rate (PEFR) and asthmatic attacks that developed at irregular intervals in spite of inhaling beclometasone dipropionate (CAS 5534-09-8, BDP) in excess of 400 micrograms/day were treated with pranlukast (CAS 103177-37-3, Onon) 450 mg/day for 1 to 2 years and the clinical effects of its long-term administration were studied. The patients were divided into 3 groups: Group I with drug effect seen on peak expiratory flow rate (PEFR) in a short-term; Group II showing long term PEFR improvement; and Group III with no sustained improvement in PEFR. Those in the first two groups continued oral medication for 2 years, while those of the third group withdrew from medication after one year and their clinical course was observed. The evaluation parameters were: PEFR, frequency of beta 2-stimulant inhalation, number of night time visits to health service facilities, quantity of inhalation steroids used, amount of oral steroids used at fixed intervals, peripheral eosinophil count, serum eosinophil cationic protein (ECP) concentration and FEV1.0. In Group I, the frequency of beta 2-stimulant inhalation, number of night time visits to health service facilities, quantity of inhalation steroids used, and the amount of oral steroids used at fixed intervals were reduced; and after two years, the frequency of beta 2-stimulant inhalation and quantity of inhalation steroids used were further reduced. In Group II, reductions were seen in the peripheral eosinophil count and serum ECP level. The asthmatic severity shifted from step 3 to 2 in 12 patients and from step 4 to 3 in 4 patients in Group I; and from step 3 to 2 in 3 patients in Group II. In Group III, an increase in the number of night time visits to health service facilities after the medication was interrupted and a rise in the serum ECP concentration were recognized.  相似文献   
89.
A 53-year-old male was scheduled for repairs of cerebrospinal fluid (CSF) rhinorrhea and pneumocephalus under general anesthesia. He had undergone a neck clipping for a ruptured anterior communicating aneurysm 13 days before. As he had a difficult airway, Trachlight was used for successful tracheal intubation. To avoid tension pneumocephalus, an intubating laryngeal mask (ILM) was inserted with rapid sequence induction without positive pressure ventilation. A 7.0 mm ID straight silicone reinforced tube was then inserted through the ILM using a fiberscope. A fiberscope guided tracheal intubation via the ILM is recommended for patients with CSF rhinorrhea and pneumocephalus especially when the trachea is difficult to intubate under direct laryngoscopy.  相似文献   
90.
Time-dependent changes in lung fields after chest irradiation were analyzed using multidetector-row CT. Routine scans at 3-mm raw thickness and 8-mm recon thickness and precision scans at 0.5-mm raw thickness and 0.5-mm recon thickness were compared with respect to the number of each finding and the time-dependent changes in the rate of each finding. Among the findings visualized by these scans, ground-glass opacity (GGO) showed the highest overall appearance rate. Precision scans exceeded routine scans in the rates of all findings except GGO and confluent shadows, and the two types of scans showed the greatest difference in the rate of GGO. Since we found that GGO tended to be overestimated on routine scans, we confirmed it by a phantom experiment. Precision scans were similar or superior to routine scans in the rates of findings except 3 months after irradiation. We consider that the concomitant use of precision scans is useful in that it allows more accurate evaluation of various post-irradiation changes in lung fields including GGO, in which the lesion is in a reversible stage.  相似文献   
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