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21.
A case is reported of Wilms' tumor associated with multiple pulmonary metastases histologically showing maturation of the tumor cells at 9 years after the resection of the primary tumor and intensive therapy. A huge tumor of a 22-month-old patient's right kidney was resected. The tumor was diagnosed as Wilms' tumor of mesenchymal type (stage 1), which consisted of predominantly immature mesenchymal tissue including rhabdomyoblasts, smooth muscle and fibrous tissue, and few blastemal and epithelial components. Intensive preoperative and postoperative chemotherapy with actinomycin D and vincristine and postoperative irradiation therapy totaling 16 Gy were carried out. The patient was regularly followed up uneventfully until 9 years after the surgery. On routine chest x ray at the age of 10 years 11 months, multiple pulmonary nodules were found. The excised nodules from the bilateral lungs disclosed similar histology, exclusively composed of dense collagen bundles and fibrocytes intermingled with mature striated muscle bundles. No immature tumor components were detected. The possible effect of intensive therapy in this maturation was stressed, although spontaneous benign differentiation of tumor cells cannot be excluded.  相似文献   
22.
Blood pressure and heart rate changes were recorded on supine or prone head-up tilt and on carotid artery occlusion in normal and streptozotocin diabetic rats (65 mg/kg). In general supine tilt induced a larger blood pressure fall, slower blood pressure recovery from the fall and larger heart rate fall than prone tilt, both in normal and diabetic rats. Heart rate recovery from the fall was slightly larger in prone than in supine tilt in normal rats. The blood pressure fall and heart rate fall accompanying the tilt were statistically larger in diabetic than in normal rats. Furthermore, blood pressure recovery from the fall was statistically more rapid and larger in normal than in diabetic rats. The exaggerated blood pressure fall with the tilt of diabetic rats might correspond to postural hypotension. Blood pressure rise and heart rate rise with carotid artery occlusion were smaller in diabetic than in normal rats. Blood pressure changes with cervical sympathetic or vagus stimulation were almost the same in normal and diabetic rats. However, in diabetic rats such cervical autonomic nerve stimulation produced larger heart rate changes than in normal rats.  相似文献   
23.
To differentiate focal nodular hyperplasia (FNH) from other hepatic tumors, especially hepatocellular carcinoma, we evaluated the hemodynamics of histologically proved FNH in three patients, two by arterial angio-CT and one by microangiography of the resected specimen. These studies demonstrated the centrifugal blood supply of FNH (early filling of central tumor vessels radiating to periphery, and lobulated tumor stains with central low density area in the late phase), which could not be demonstrated by dynamic CT or hepatic angiography. Arterial angio-CT is useful as a further study, when differential diagnosis of FNH is uncertain by other imaging techniques.  相似文献   
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25.
A 6-year-old boy was successfully operated on for double outlet ventricle, common atrioventricular canal with severe valvular regurgitation, right atrial Isomerism, L-loop ventricles, total anomalous pulmonary venous connection, and pulmonary stenosis with hypoplastic left pulmonary artery. The Interventricular rerouting from the left ventricle to the ascending aorta was performed with a spiral patch, the lnteratrlal switching was performed by a Mustard patch, the common atrioventricular orifice was partitioned and valve repair was performed, and an 18-mm valved conduit was inserted between the right ventricle and the pulmonary artery. Although the patient had a small residual ventricular septal defect and pulmonary stenosls, the patient Is alive and well.  相似文献   
26.
The effects of 12 essential oils, popularly used as antifungal treatments in aromatherapy, on growth of Candida albicans were investigated. Mycelial growth of C. albicans, which is known to give the fungus the capacity to invade mucosal tissues, was inhibited in the medium containing 100 micro g/ml of the oils: lemongrass (Cymbopogon citratus), thyme (Thymus vulgaris), patchouli (Pogostemon cablin) and cedarwood (Cedrus atlantica). Not only lemongrass oil but also citral, a major component of lemongrass oil (80%), in the range of 25 and 200 micro g/ml inhibited the mycelial growth but allowed yeast-form growth. More than 200 micro g/ml of citral clearly inhibited both mycelial and yeast-form growth of C. albicans. These results provide experimental evidence suggesting the potential value of lemongrass oil for the treatment of oral or vaginal candidiasis.  相似文献   
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28.
The diagnosis and choice of treatment for dermatophytoses are usually based on the result of microscopic observation of hyphal elements and culture. However, false negative cultures have sometimes been encountered and appropriate timing of discontinuation of treatment has not been formulated. In this study, we attempted the identification and viability assessment of dermatophytes based on the quantitative measurement of dermatophyte actin (ACT) mRNA. An internal fragment of the ACT, 725 to 762 bp, was isolated by PCR from the genomic DNA of dermatophytes and sequenced. ACT intron-based primers were dermatophyte species-specific and primer pairs crossing the intron were dermatophyte genus-specific. The LightCycler (LC) instrument, employing the two-step RT-PCR/fluorescent hybridization system, was used to quantify the actin mRNA (ACT) of dermatophytes. A 669 bp ACT cDNA fragment was used as a quantification standard. Several mg of samples were collected from skin scales or nail plates before and after the treatment using oral terbinafine. The results indicated that quantification of ACT mRNA correlated with the results of culture and KOH examination and that copy numbers of dermatophyte ACT mRNA per mg sample decreased with progression of the therapy. This method comprises a sensitive (1 fg), specific, rapid (< 4 h) and quantitative assessment of the viability and identification of dermatophytes in skin tissue.  相似文献   
29.
We have studied the effect of intrathecal administration of N-methyl-D- aspartate (NMDA) receptor antagonists on the minimum alveolar anaesthetic concentration (MAC) of isoflurane in rats. In Wistar rats fitted with indwelling intrathecal catheters, we determined the MAC of isoflurane after administration of a competitive NMDA receptor antagonist, APV (0.01, 0.1, 1.0, 10, 30 micrograms), a non-competitive NMDA receptor antagonist, MK801 (0.1, 1.0, 10, 30 micrograms). NMDA (0.01, 0.1, 1.0, 10, 30 micrograms) and saline. APV at all doses except 0.01 micrograms decreased MAC by 17.1-32% (P < 0.001 and P < 0.0001). Although MK801 at 10 and 30 micrograms reduced MAC by 24.3-31.7% (P < 0.001 and P < 0.0001), lower doses did not affect MAC. Intrathecal administration of NMDA reversed these decreases in MAC, but not to control values with APV 10 and 30 micrograms and MK801 30 micrograms. We suspect that NMDA and NMDA receptor antagonists play important roles in the spinal cord in determining the MAC of isoflurane.   相似文献   
30.
A 66-year-old woman time of 10 days. One month after radicalmastectomy, there was local recurrence, followed by multiplepulmonary metastases, and the patient died of respiratory failure5 months after surgery. The gray-white-colored tumor measured13x12x;10 cm, and its border was well defined. The tumor wascomposed of diffusely growing round or polygonal cells withvesicular nuclei, prominent nucleoli, and ample cytoplasm containingeosinophilic inclusions. Lymph node involvement was widespread.Both vimentin and keratin were clearly demonstrated by immunohistochemicalstaining. Ultrastructural studies revealed that the MRT cellscontained cytoplasmic whorls of intermediate filaments.  相似文献   
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