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41.
The effects of an intracoronary administration of iomeprol, a new nonionic tri-iodinated water-soluble contrast medium, on coronary circulation were compared to those of iopamidol and those of nitroglycerin in 6 chronically instrumented conscious dogs. A pair of 10 MHz piezoelectric crystals and an electromagnetic flow probe were placed on the left circumflex coronary artery (LCCA) to measure the epicardial coronary diameter (CD) and coronary blood flow (CBF). Polyethylene tubing for drug administration was inserted into the LCCA proximal to the sonomicrometers. Iomeprol at the dose of 1 ml and 3 ml/min for 1 min significantly increased CD by 0.6±0.1% and 1.4±0.3%, respectively and CBF by 44.5±9% and 70±10%, respectively. Iopamidol at the same rates also significantly increased CD by 0.8±0.1% and 1.5±0.3% and CBF by 50±11% and 82±14%, respectively. There was no statistically significant difference between iomeprol-and iopamidol-induced increases in CD and CBF. However, the duration of the increase in CD was significantly shorter (p<0.05) after iomeprol than after iopamidol. Nitroglycerin (10 μg/kg) significantly increased CD by 4.5±1% and CBF by 105±10%. The increases in CD and CBF in response to iopamidol and iomeprol were significantly smaller (p<0.01) than to nitroglycerin. We conclude that vasodilating effects of iomeprol and iopamidol on the large epicardial coronary artery and coronary blood flow are comparable in conscious dogs and significantly lower than after nitroglycerin in the doses used by us. This study was supported by a grant from the EI-ZA1 Pharmaceutical Co., Tokyo, Japan.  相似文献   
42.
Magnetic resonance imaging (MRI) has greatly facilitated morphologic evaluation of spinal cord lesions. Eleven cases representative of inflammatory, demyelinating, neoplastic and vascular diseases, are presented which illustrate and summarize important abnormal features in spinal cord imaging, particularly MR findings. Recently, specialised techniques such as MR angiography, fat-inhibiting methods, dynamic MRI and functional imaging have been developed. These methods have facilitated not only lesion diagnosis but also qualitative assessment, and are being used to analyze pathophysiology. Comprehensive diagnoses based on such modalities may be important in determining indications for surgery or defining the extent of surgery or the intensity of other treatments.  相似文献   
43.
A case of active prosthetic valve infective endocarditis (PVE) due toCandida glabrata was successfully treated by the systemic administration of fluconazole. A 66-year-old Japanese man with infective endocarditis of unknown etiology underwent aortic and mitral valve replacement to treat severe aortic and mitral regurgitation associated with multiple organ failure. Postsurgical cultures of arterial blood were repeatedly positive forC. glabrata, and therefore fluconazole was administered either intravenously or orally at a dose of 400 mg/day for 46 days. During that time the signs of inflammation including fever such as an elevated white blood cell count and the presence of C-reactive protein (CRP) all improved while the blood cultures became negative. Fluconazole is thus considered to be effective in treating PVE caused byC. glabrata. When administering this treatment, it is also important to monitor the patient's renal and liver function.  相似文献   
44.
The ovarian and pituitary functions of 64 operable breast cancer patients undergoing adjuvant therapy with cytotoxic chemotherapy and/or tamoxifen were investigated. The post menopausal patients, divided into 3 treatment groups, one with tamoxifen alone, one with tamoxifen and chemotherapy and the other with chemotherapy alone had serum estradiol 17-β (E2) and progesterone levels lower than the evaluable limits. Although there was no significant difference in the level of estrone sulfate (E1-S) between these three groups, the level of lutainizing hormone (LH) and follicle stimulating hormone (FSH) in the patients treated with tamoxifen alone and tamoxifen and chemotherapy were significantly lower than those treated with chemotherapy alone. The decrease in gonadotropin levels induced by tamoxifen treatment was reversible as it appeared after the initiation of tamoxifen and recovered after its cessation. In the premenopausal patients, a group treated with tamoxifen and chemotherapy had significantly higher E1-S, E2 and progesterone levels and significantly lower gonadotropin levels than a group treated with chemotherapy alone or one treated with a cyclophosphamide regimen. These increases in the levels of estrogen and progesterone were also reversible, and induced by tamoxifen. Thus, adjuvant endocrinochemotherapy causes profound alteration in the hypothalamo-pituitary-ovarian axis and therefore, monitoring a variety of hormonal levels is thought to be necessary for assessing the consequences of adjuvant therapy in breast cancer patients, especially in premenopausal patients using tamoxifen.  相似文献   
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46.
Recent DNA studies performed by several groups have detected mutations of the gene encoding fibroblast growth factor receptor 3 (FGFR3) in patients with achondroplasia-group disorders, including achondroplasia (ACH), hypochondroplasia (HCH), and thanatophoric dysplasia (TD). For this study, we analyzed theFGFR3 gene in 31 Japanese patients with typical ACH, four with HCH, three with a condition intermediate between ACH and HCH (ACH/HCH-intermediate), and one with TD. Of the 31 typical ACH patients, 29 showed a G1138 to A transition and the other two a G1138 to C transversion, both resulting in a common Gly380Arg substitution in the transmembrane domain of FGFR3. The one TD and the four HCH patients did not display any mutations in the transmembrane domain of FGFR3. Of the three ACH/HCH-intermediate cases, one patient showed the Gly380Arg substitution and one did not, and further analysis of the second patient revealed the presence of Asn540Lys substitution. The first patient was, therefore, genotypically diagnosed as ACH and the second as HCH. Peripheral blood leukocyte DNA analysis in the remaining ACH/HCH-intermediate patient indicated an unequal ratio of mutant to normal PCR products, possibly representing a somatic mosaic for the Gly380Arg mutation. Analysis of the common FGFR3 mutation thus appears to help in the molecular diagnosis of patients with achondroplasia-group disorders.  相似文献   
47.
Purpose: To evaluate the efficacy of transcatheter oily chemoembolization (TOCE) for hepatoceliular carcinoma (HCC) on the basis of microscopic and macroscopic findings postembolization. Methods: HCCs ranging in size from 0.5 to 13 cm (mean 3.6 cm) were obtained from partial hepatectomies of 100 consecutive patients who had undergone TOCE between 20 and 246 days (mean 59.5 days) prior to surgery. The efficacy of TOCE was assessed on the basis of the necrotic to live cell ratio of the tumors. The microscopic pattern of tumor growth was grouped into expanding type (complete capsule formation) and replacing type (incomplete or no capsule). There were five types of macroscopic groupings: single nodule, single nodule with extranodular growth (SNE), contiguous and noncontiguous multinodular, and massive growth type. Results: Among 79 cases with the expanding type, 29 (37%) had 100% HCC necrosis, but none with 100% necrosis were in the replacing type. By macroscopic grouping, the efficacy of TOCE decreased from the single nodule type (50% of patients had 100% necrosis) to the SNE type (21%), and the other types (9%).  相似文献   
48.
Summary BS compounds, a series of new dihydropyridines, successfully overcame multidrug resistance in P388/ADR cells in vitro. These agents synergistically potentiated the cytotoxicity of Adriamycin to P388/ADR cells at a concentration of 1–2 M, whereas they showed hardly any synergistic effect in the parental cell line (P388/S) at the same concentration. They inhibited the active drug efflux in P388/ADR cells as well as the binding of [G-3H]-vinblastine to membrane vesicles from P388/ADR, which was increased in resistant P388 cells as compared with parental cells. Besides, unlike the activity of clinically used calcium antagonists, the calcium antagonistic activity associated with BS compounds was very weak: their arterial relaxation activity was <21% of that of verapamil. These data suggest that BS compounds specifically overcome multidrug resistance without the serious hypotensive side effects that accompany the use of verapamil orother calcium antagonists.  相似文献   
49.
The purpose of this study was to compare the MR characteristics of renal cell carcinomas against histologic findings and to assess the correlations among signal intensity, tumor enhancement, and pathologic findings. Fifty-four patients (56 lesions) were examined by MR imaging and then underwent partial or radical nephrectomy. The pathologic diagnosis of all lesions was renal cell carcinoma. All MR examinations were performed as dynamic studies using the same 1.5-T scanner. MR characteristics were compared against pathologic findings after resection, and the correlations among signal intensity, tumor enhancement, and pathologic findings were then assessed. A significant correlation was observed between tumor grade and tumor enhancement, with G3 lesions tending to show little enhancement. Regardless of the histologic classification, G3 tumors were found to contain highly heterotypic cancer cells and very few vessels by histopathologic examination. No significant correlations were noted between the other MR characteristics and pathologic findings. Renal cell carcinomas showing little enhancement tend to be highly malignant lesions based on the pathologic findings. Special consideration is required for these tumors with regard to the selection of surgical intervention and follow-up observation.  相似文献   
50.
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