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31.
32.
Biosynthesis of griseolic acids, competitive inhibitors of cyclic nucleotide phosphodiesterase, was investigated with the culture of a producing strain of Streptomyces griseoaurantiacus. 13C-Labeled and 15N-labeled compounds were added into the culture, and 13C-enriched and 15N-enriched griseolic acid A was isolated from the culture medium and analyzed by 13C NMR and 15N NMR spectroscopy. The compounds added to growth medium were [2-13C]acetate, [1,2-13C]acetate, [1,4-13C]succinate, [1-13C]glucose, [6-13C]glucose, [2-13C]ribose, and [1-13C, 15N]glycine. The results suggest that adenosine, which is formed from amino acids and sugars contributes the adenine and ribose moieties to griseolic acid A. The data also suggest that a dicarboxylic acid from the Krebs tricarboxylic acid cycle contributes to the dicarboxylic part of the compound.  相似文献   
33.
In vivo administration of chloroquine to rats caused an increase in the pH of hepatocyte lysosomes within 1 hr after administration with a return to baseline pH values by 3 hr; continued administration of chloroquine for up to 12 days was unaccompanied by any further changes in hepatocyte lysosomal pH. We interpret these data as evidence against a major role for an increase in the pH of hepatocyte lysosomes in CAC-induced phospholipidosis.  相似文献   
34.
A 58-year-old woman was admitted due to an abnormal shadow on chest X-ray, without any symptoms. Chest computed tomography showed a round mass in the anterior segment of the right upper lobe. Segmentectomy was performed and histopathological examination revealed a primary neurogenic tumor of Schwann cell origin. Immunohistochemical staining demonstrated the presence of S-100 protein in the tumor cells. We present a case of intrapulmonary schwannoma and review 62 cases of primary schwannoma of the lung.  相似文献   
35.
PURPOSE: To evaluate the treatment results of low-dose-rate (LDR) and high-dose-rate (HDR) interstitial brachytherapy (ISBT) for T3 mobile tongue cancer. MATERIAL AND METHODS: Between 1974 and 1992, 61 patients with T3 mobile tongue cancer were treated with LDR ISBT using (192)Ir hairpins with or without single pins. In addition, between 1991 and 1999, 14 patients were treated with HDR ISBT. For nine patients treated with ISBT alone, the total dose was 59-94 Gy (median 72 Gy) within one week in LDR ISBT and 60 Gy/10 fractions/5 days in HDR ISBT. For 66 patients treated with a combination therapy of external beam radiotherapy (EBRT) and ISBT, the total dose was 12.5-60 Gy (median 30 Gy) of EBRT and 50-112 Gy (median 68 Gy) within 1 week in LDR ISBT or 32-60 Gy (median 48 Gy)/8-10 fractions/5-7 days in HDR ISBT. RESULTS: The 2- and 3-year local control rates of all patients were both 68%. The 2- and 3-year local control rates of patients treated with LDR ISBT were both 67%, and those with HDR ISBT were both 71%. The local control rate of patients treated with HDR ISBT was similar to those with LDR ISBT. CONCLUSIONS: ISBT for T3 mobile tongue cancer is effective and acceptable. The treatment result of HDR ISBT is almost similar to that of LDR ISBT for T3 mobile tongue cancer.  相似文献   
36.
We assessed the relations of visual hallucinations (VH) to cardiovascular autonomic dysfunction in patients with Parkinson's disease (PD). The subjects were 37 patients without VH (VH(-)) and 31 with VH (VH(+)). Autonomic function was evaluated on the basis of cardiac 123-radioiodinated metaiodobenzylguanidine (123I-MIBG) uptake and hemodynamic testing with Valsalva maneuver. Systolic blood pressure (SBP) and plasma norepinephrine concentrations (NE) were measured by tilt-table testing. 123I-MIBG uptake was lower in VH(+) than VH(-). Hemodynamic studies showed that VH(-) had only cardiac sympathetic and parasympathetic dysfunction, while VH(+) additionally had reduced vasomotor sympathetic functions. The fall in SBP during tilt-table testing was greater in VH(+) than VH(-). NE and its difference in the supine and upright positions were decreased in VH(+). We conclude that cardiac and vasomotor sympathetic dysfunction is more severe in VH(+) than in VH(-). Severe dysfunction in PD with VH is probably attributed to Lewy-body lesions or neuronal loss in sympathetic ganglia, the central autonomic system, or both.  相似文献   
37.
We previously reported the hyperosmolarity response (a decrease of the ocular standing potential by hyperosmolarity) as a new clinical test of the retinal pigment epithelium (RPE) activity. In the present study a hypertonic solution (Fructmanit, 1.4 × 103 m0sm/1) was intravenously injected for 20 min in proportion to a subject's total blood volume (TBV). At the injection speed of 5, 10, and 15% of the subjects' TBV per hour the mean amplitude of the hyperosmolarity response in normal subjects was 19.7, 30.1 and 36.4% respectively. The amplitude of the hyperosmolarity response depends on the logarithm of the dose of the hypertonic solution within the range of the dose tested.We previously found that hyperosmolarity suppresses the light rise. The present study investigated this suppressive effect in a quantitative manner. The light rise (a full-field illumination of 1.2 × 103 cdl/m2) was dose-dependently suppressed by Fructmanit. The mean of the light rise to dark trough ratio in normal subjects was 1.81 with no osmotic stress, and 1.64, 1.41 and 1.29 respectively at the injection speeds of 5, 10, and 15%. The suppression of the light rise by hyperosmolarity is compatible with the view that the hyperosmolarity response and the light rise share the basal membrane of the RPE as the main site of their generation.  相似文献   
38.
A 51-year-old woman, with progressive gait disturbance and dysarthria, had been diagnosed as Menzel-type spinocerebellar degeneration. Later, she developed dystonic posture of upper limbs and bulging eyes. She was diagnosed as Machado-Joseph disease from neurological findings, which consisted of cerebellar signs, pyramidal tract signs and extrapyramidal tract signs and peripheral neuropathy. She died suddenly of unknown origin. Her illness lasted about 13 years. Neuropathological findings showed moderate neuronal loss with gliosis in the subthalamic nucleus, globus pallidus, substantia nigra, dentate nucleus, oculomotor and hypoglossal nucleus and anterior horn. Positron emission tomography (PET) using 15O steady state inhalation technique revealed reduction of cerebral blood flow and cerebral metabolic rate of oxygen in not only cerebellum but also cerebral cortex. These findings are different from typical PET findings of spinocerebellar degeneration.  相似文献   
39.
This report describes an experimental model of chronic tonsillar herniation and its effects on the spinal cord. In ten rats, a small piece of chemically induced mammary cancer was transplanted to the supraoccipital bone. In all cases, the transplanted cancers grew into the posterior fossa, destroying the supraoccipital bone and compressing the cerebellum extradurally. In six of the ten rats, tonsillar herniation was observed at 8–14 weeks after transplantation. Transdural infiltration of the tumor cells was not apparent in any animal. In those rats with tonsillar herniation (n=6), the spinal cord from the C5 to the T8 segments showed enlargement of the central canal without exception. Histological examination revealed the following changes: stretching and thinning of the ependymal cells; swelling of the astrocytic processes; and extracellular edema, predominantly in the dorsal gray matter, but also in the ventral inner portion of the dorsal column. In the control group (n=4) and those rats without tonsillar herniation (n=4), such histological changes of the spinal cord were not observed. Although the lesions can not be regarded as representing mature syringomyelia, they most likely constitute an earlier evolutionary stage.  相似文献   
40.
Recent progress in molecular biology suggests a certain relationship between penile cancer and human papilloma virus infection. However, the treatment for penile cancer has not been established since each institute has experienced only a small number of patients. We analyzed the result of our treatment for 14 penile cancer patients during past twenty years. Ten of the 14 patients were initially treated for the primary lesion with a combination of peplomycin (PEP) or bleomycin (BLM) and radiation therapy. Of these, 9 were found not to have residual viable cancer cells in their primary lesions. No local recurrence was found in all 7 patients in whom the penis was preserved. This result suggests that combination of PEP (BLM) and radiation preserves the penis without increasing the risk of local recurrence. Penile cancer-related death did not occur in patients without lymph node metastasis. However, this cancer death did occur in 4 out of 7 patients with lymph node metastasis, suggesting that metastasis is one of the important prognostic factors. PEP (BLM) and radiation therapy with or without regional lymph node dissection did not improve the prognosis of patients with advanced penile carcinoma, such as with pN2, pN3 or distant metastasis. More effective management may be necessary for these patients.  相似文献   
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