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11.
The present study was designed to investigate the presynaptic alpha 2-adrenoceptor function to inhibit norepinephrine (NE) release in blood vessels of reduced renal mass salt hypertensive rats (Na-loaded HT). Isolated perfused mesenteric vasculatures were prepared from Na-loaded HT and normotensive control rats (NT-control), and the NE release and vascular responsiveness were examined. Periarterial nerve stimulation caused a significantly greater release of NE and pressor responses in Na-loaded HT than in NT-control. Yohimbine, a potent alpha 2-adrenoceptor antagonist, demonstrated the facilitatory effects on NE release during nerve stimulation. The effects were significantly attenuated in Na-loaded HT compared with NT-control. These results demonstrate that vascular sympathetic nervous activity might be enhanced in Na-loaded HT. Furthermore, the increased NE release from vascular adrenergic neurons in Na-loaded HT could partially depend on impaired presynaptic alpha 2-adrenoceptor-mediated modulation, which might contribute to the pathogenesis and maintenance of this form of salt-dependent hypertension.  相似文献   
12.
One of the most problematic aspects of surgery for hepatocellular carcinoma (HCC) is the frequent development of multiple tumors. Determination of the origin of multiple tumors, i.e., multifocal or metastatic, is important for predicting the clinical course of the disease after surgery. In order to clarify the origin of multiple tumors of HCC genetically, we examined patterns of loss of heterozygosity (LOH) on chromosome 16 for DNA isolated from 43 HCCs resected from 19 patients by analysis of restriction fragment length polymorphism. The cases were classified macro- and microscopically into 3 groups: multifocal origin; metastatic origin; and undetermined. Classification based on morphological features was shown to be well correlated with patterns of LOH in multiple tumors of HCC. Different patterns of LOH on chromosome 16 were detected in 8 of 11 patients with tumors of morphologically multifocal origin, whereas they were detected in none of 5 patients with tumors of morphologically metastatic origin. Among five patients with tumors of morphologically undetermined origin, a difference of LOH pattern among the tumors was detected in two, whereas in the other three, the pattern was identical between the tumors. A different pattern of LOH among HCCs arising in situ showed that they were composed of different clones, strongly suggesting their independent clonal origin and multifocal development. These results show that not only appropriate morphological observation but also examination of the LOH pattern on a particular chromosome is useful in diagnosis of multifocal HCC.  相似文献   
13.
BACKGROUND: We have developed velocity-flow urodynamics using Doppler sonography based on the hypothesis that microbubbles formed in the urethra are responsible for Doppler signals. In order to confirm this hypothesis derived from Bernoulli's principle, we investigated the simultaneous detection of cavitation noise and Doppler signals in an experimental system. METHODS: An experimental circuit was built in which a stenosis was created using a glass or silicon tube with tap water used as the sample fluid. Doppler signals, pressure before and after the stenosis, flow rate, flow velocity and cavitation noise were measured. Direct detection of cavitation with a high-speed charged-coupled device (CCD) camera was conducted in the glass tube. The relationship between cross-sectional area and flow velocity in terms of the detection of Doppler signals was analyzed in the silicon tube study. RESULTS: In the glass tube study, a high-speed CCD camera clearly detected masses of microbubbles associated with cavitation. The range of flow rates creating cavitation completely corresponded with those producing Doppler signals detected by ultrasonography. A similar correlation was observed in the silicon tube study, which showed that a low flow velocity of 41.5 cm/sec through a stenosis with a cross-sectional area of 20 mm(2) created Doppler signals at a flow rate of 8.3 mL/sec. CONCLUSION: The results of the present study confirmed that microbubbles created in flowing urine are responsible for Doppler signals. Measurement of velocity-flow urodynamics has great potential to become a non-invasive and reliable alternative to conventional pressure- flow urodynamic studies.  相似文献   
14.
AIM: We administered the herbal medicine Dai-Kenchu-To (DKT) to children with severe chronic constipation or with severe constipation after surgery for anorectal malformations. We then objectively assessed the effect of DKT on anorectal function by manometric study in addition to using a clinical scoring system. PATIENTS AND METHODS: Ten children with severe chronic constipation and 5 children with severe constipation after surgery for anorectal malformations were assessed. These 15 children received 0.3 g/kg/day of DKT for periods ranging from 3 months to 1 year. We objectively assessed their bowel function, sphincter function and rectal reservoir function by anorectal manometry and clinical scoring. RESULTS: In 10 children with severe chronic constipation, the clinical score after administration of DKT (7.2 +/- 0.8) improved significantly compared with that before administration of DKT (4.6 +/- 2.9) (p < 0.02). The threshold sensation volume and the maximum tolerable volume after administration of DKT significantly (p < 0.05; p < 0.01) decreased (128 +/- 63 ml vs. 69 +/- 18 ml; 229 +/- 99 ml vs. 144 +/- 47 ml), and rectal compliance after administration of DKT also significantly (p < 0.05) decreased (12.4 +/- 10.9 ml/cmH(2)O vs. 4.7 +/- 3.9 ml/cmH(2)O). CONCLUSION: The present study demonstrated that DKT had a favorable clinical effect on severe constipation in children, and anorectal manometry showed an improvement in their rectal reservoir functions. It appears that the results were secondary to DKT-stimulated peristalsis of the intestine, which promoted regular bowel habits.  相似文献   
15.
Phenytoin is a highly effective anticonvulsant agent that is widely administrated to prevent some kinds of patients with brain tumor. But it has been said that phenytoin may have some immunosuppresive potential for hosts. In this study, we evaluated the effects of phenytoin upon cellular immunity such as NK, CTL and LAK activity in murine models. Fresh splenocytes were taken out from mice (CBA/J, C 3 H/HeN, C 57 BL/6) into which phenytoin had been injected intraperitoneally at a daily dose of 1,000 micrograms for 28 days. The serum concentration of phenytoin in the experimental models was 10-20 micrograms/ml. The cytotoxic activities were estimated by a 4-hr 51Cr release assay. The mitogen-stimulated lymphocyte function was evaluated by 3H-thymidine incorporation into DNA. The NK activity was estimated by cytotoxicity of splenocytes of CBA/J mice against NK-sensitive YAC-1 cells. The cytotoxic T-lymphocyte (CTL) activity was estimated by cytotoxicity of splenocytes of C 57 BL/6 mice which were stimulated in vitro for 5 days by splenocytes of C 3H/HeN treated with mitomycin C, against RSV-M glioma cells. Lymphokine-activated killer (LAK) activity was estimated by cytotoxicity of LAK cells, which were induced from splenocytes of C 3 H/HeN mice by human recombinant interleukin-2 (rIL-2), against syngeneic RSV glioma and allogeneic 203 glioma cells. 3H-thymidine incorporation of splenocytes of C 57 BL/6 mice was reduced significantly (p less than 0.01) in phenytoin-treated mice. The cytotoxicity of splenocytes of non-treated CBA/J mice against YAC-1 cells was 75%, but that of phenytoin-treated CBL/J mice was a few %.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
16.
A Ueyoshi  Y Kiura  K Ota  T Tsuda  E Shimizu 《Ryūmachi》1991,31(3):267-274
Rheumatoid arthritis (RA) occurred frequently in women. Exogenous estrogen has been reported to alleviate the symptoms of patients with RA. But the implications of sex hormones and immunological abnormalities in RA remain to be elucidated. Therefore, we measured sex hormones (LH, FSH, estradiol, testosterone and prolactin), bone metabolic markers (midregion and carboxy terminal mainly recognized PTH1-84, intact PTH1-84, bone GLA protein and alkaline phosphatase), bone mineral, in lumbal bone with quantitative tomography (QCT) and with of cortex with microdensitometry in 52 females with RA and 46 females with osteoarthritis (OA) as a control group. Sex hormones and bone metabolic markers were analyzed as independent variables of serum LH, FSH and estradiol levels, using one way analysis, in patients with RA and OA. The more increased serum FSH and LH levels were, the more decreased serum estradiol levels were in both RA and OA groups, when they were considered as independent variables. These results indicate that the secretory function of pituitary and ovary axis hormones are normally enacted in RA. On the other hand, when the sex hormones of the patients under 53 years of age were studied in both groups, serum FSH adn LH showed significantly higher levels, while serum estradiol levels revealed decreased tendency in RA, compared with these in RA. Thus the pituitary ovary secretory function in patients with RA was suggested to be disturbed in early stage of age, indicating that the sex hormones would be partly implicated in calcium and bone metabolism in patients with RA.  相似文献   
17.
A 68-year-old woman had pulmonary aspergilloma in the right upper lobe with old cavitary pulmonary tuberculosis. Despite intravenous fluconazole there was no change in the size of the fungus ball. Endobronchial instillation of fluconazole also failed. Subsequently percutaneous instillation of fluconazole was attempted with localized drainage. The fungus ball decreased in size after 8 weeks. Although slight hemoptysis and subcutaneous emphysema occurred in this case, these condition required no treatment. This method of treatment appears to be useful for inoperable cases of pulmonary aspergilloma.  相似文献   
18.
A continuous cell line, named SMC R86 F1, was established from a surgically resected primary thyroid lesion. The cell grew as an adhering monolayer with a doubling time of about 25 hours in modified Eagle's medium supplemented with fetal bovine serum. When the cells were transplanted into athymic nude mice, tumors developed at the site of inoculation. The cells not only showed epithelial origin upon light and electron microscopic examination but also possessed a biosynthetic marker human thyroglobulin (hTg). In order to examine the iodide trapping ability of the xenografts, radioiodine at doses of 3.7 MBq was injected into the peritoneum of 131I treated nude mice bearing xenografts at about 4 weeks after the cell inoculation. Judging from the results of scintigraphic, autoradiographic and biodistribution studies, viable tissue of the xenografts in the treated mice had the ability to trap radioiodine. Histological sections of the xenografts resected from the treated mice consisted of follicle-like and trabecular growing structures, and immunohistochemically the cytoplasm of the tissues was hTg positive. The cells possessed the ability to trap radioactive iodine in vitro under the control of TSH. In addition, the expression of iodinated 19S Tg in the cell cytoplasms in the monolayer cultures was revealed by immunoblotting and autoradiographic assays. These observations provide strong evidence that the SMC R86 F1 cell line possesses well-differentiated properties of the malignant thyroid follicular epithelial cells.  相似文献   
19.
Summary A case of a solid parotid tumour in a 16-year-old boy is presented. Histologically, the tumour demonstrated some peculiar findings. An acinar pattern was predominant although every component seen in the normal salivary gland was present, namely, serous and mucous gland acini, ducts, myoepithelial cells, adipose and lymphoid tissue. Large eosinophilic granules were abundant in the large acinar cell cytoplasm. Immunohistochemically, the tumour demonstrated the proteins which are present in the normal parotid gland, for example, amylase, lactoferrin and lysozyme. Electron microscopic features were quite similar to those of normal parotid tissue except for accumulation of a large number of cytoplasmic granules in the acinar cells. There has been no previous report of a tumour with the same features as seen in this case. Our pathological diagnosis is hamartoma, although the possibility of hyperplasia or neoplasia can not be excluded.  相似文献   
20.
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