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31.
Recent studies have suggested that aldosterone plays a role in the pathogenesis of renal injury. In this study, we investigated whether local angiotensin II (Ang II) activity contributes to the progression of renal injury in aldosterone/salt-induced hypertensive rats. Uninephrectomized rats were treated with 1% NaCl in a drinking solution and one of the following combinations for 6 weeks: vehicle (2% ethanol, s.c.; n=9), aldosterone (0.75 mug/h, s.c.; n=8), aldosterone+Ang II type 1 receptor blocker olmesartan (10 mg/kg/day, p.o.; n=8), or aldosterone+olmesartan (100 mg/kg/day, p.o.; n=9). Aldosterone/salt-treated hypertensive rats exhibited severe proteinuria and renal injury characterized by glomerular sclerosis and tubulointerstitial fibrosis. Aldosterone/salt-induced renal injury was associated with augmented expression of angiotensin converting enzyme and Ang II levels in the renal cortex and medullary tissues. Renal cortical and medullary mRNA expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) as well as the collagen contents were increased in aldosterone/salt-treated hypertensive rats. Treatment with olmesartan (10 or 100 mg/kg/day) had no effect on blood pressure but attenuated proteinuria in a dose-dependent manner. Olmesartan at 10 mg/kg/day tended to decrease renal cortical and medullary Ang II levels, TGF-beta and CTGF expression, and collagen contents; however, these changes were not significant. On the other hand, an ultrahigh dose of olmesartan (100 mg/kg/day) significantly decreased these values and ameliorated renal injury. These data suggest that augmented local Ang II activity contributes, at least partially, to the progression of aldosterone/salt-dependent renal injury.  相似文献   
32.
Introduction: One of the causes of pain during insertion of the colonoscope is stretching of the mesenterium by loop formation. The degree of pain differs according to the type of loop formation. Our aims were to study the accuracy of the colonoscopist’s assessment of the presence and type of loop formation and to study the degree of pain in relation to the type of loop by administering the visual analog scale (VAS). Methods: Two hundred and fifty‐seven consecutive patients were enrolled. All procedures were performed by two experienced colonoscopists who were blind to magnetic endoscope imaging view. After the colonoscopy, the colonoscopist was asked to assess the presence and type of loop formation. The degree of pain was assessed using the VAS. Results: The accuracy of estimating N loop, alpha loop, absence of loop formation and U loop was each over 70%. The accuracy of estimating gamma and splenic loop was significantly lower than the accuracy of estimating U loop. Colonoscopy was significantly more painful in women than in men. The degree of pain was significantly higher upon formation of reverse alpha loop and gamma and splenic loop than upon formation of N loop and U loop. Conclusions: Upon formation of reverse alpha loop or gamma and splenic loop, patients experienced more pain and it was difficult for the endoscopists to assess these loops. As women had severe pain compared with men, the use of a pediatric colonoscope or higher dosage of sedation in women should be considered.  相似文献   
33.
Objective: We assessed the current role of preoperative and intraoperative autologous blood donation in pediatric open-heart surgery. Methods: Group 1 consisted of 51 patients between 5 and 10 years old who underwent preoperative autologous blood donation. Group 2 consisted of 50 age-matched patients without preoperative donation as controls. Intraoperative donation was conducted in both groups prior to cardiopulmonary bypass. We evaluated perioperative blood cell count, blood loss, and the need for homologous blood products. Results: No serious complications occurred in preoperative or intraoperative donation. Total preoperative donation storage was 17.5±3.4 mL/kg. Intraoperative donation was 21.7 ±6.1 mL/kg in Group 1 and 12.8±4.0 mL/kg in Group 2 (p<0.001). On admission, serum hemoglobin was lower in Group 1 (12.2±1.0 g/dL versus 13.6±1.6 g/dL, p<0.001) but returned postoperatively to the preoperative value. It hovered at a depressed level in Group 2 (12.2±1.4 versus 10.2±1.1 g/dL, p<0.001). The homologous blood requirement was significantly less in Group 1 than in Group 2 (0% versus 10%, p<0.05). Postoperative platelet counts showed similar curves, and blood loss was not statistically significantly different between groups. Conclusion: Preoperative and intraoperative donations are safe and continue to contribute uniquely to blood conservation, providing important options in comprehensive blood conservation programs in current pediatric open-heart surgery.  相似文献   
34.
Some chordomas have a very poor prognosis because of their aggressive growth nature, but the efficacy of repeat operations for these cases has not been well documented. This report concerns 3 patients with aggressive chordoma of the clivus, who underwent operations 6 to 12 times over a period of 8 to 17 years because of symptomatic regrowth. Overall mean interval between repeat operations was 18 months with a range from 5 to 57 months and survival times were 9 to19 years after the first surgery. Main symptoms before each operation were diplopia and visual disturbance. Repeat palliative operations by intentional extradural debulking of the tumour to decompress offending neural structures, as well as maximal removal of the tumour, using appropriate skull base approaches, can mitigate progressive symptoms, and may result in better quality and some prolongation of life, although our patients gradually deteriorated neurologically throughout the clinical course.  相似文献   
35.
A 52-year-old woman who had had 6 months of chemotherapy using mitomycin C and cisplatin for cervical cancer presented with hemolytic uremic syndrome. Conventional plasmapheresis using whole-plasma fraction was ineffective. However, plasmapheresis using the cryosupernatant fraction dramatically improved symptoms of hemolytic anemia and thrombocytopenia in this case. The activity of factor VIII in the cryosupernatant fraction of plasma as a replacement fluid decreased after removal of cryoprecipitate, indicating effective removal of von Willebrand factor. The pathogenesis of her hemolytic uremic syndrome may have been associated with von Willebrand factor multimers contained in the cryoprecipitate of plasma. Similar use of the cryosupernatant fraction of plasma could not be found in other reports of cases of hemolytic uremic syndrome. Plasmapheresis using the cryosupernatant fraction of plasma may improve refractory hemolytic uremic syndrome.  相似文献   
36.
A rare case of solitary bronchial papilloma was reported. A 57-year-old male was admitted to our hospital because of an abnormal shadow on chest X-ray film which was discovered on regular health check up. Bronchoscopic examination revealed a polypoid tumor which obstructed the left B4 bronchus. Serum concentration of CEA was elevated up to 14 ng/ml by Z-GEL method. Left upper lobectomy was performed. On macroscopic examination of the excised specimen, the tumor arose in B4 bronchus and was yellowish white in color and was cauliflower-like in shape sized 3.5 X 1.5 cm. Histopathologically, the tumor consisted of papillary proliferation of stratified squamous epithelium with ciliated columnar epithelial covering. Findings suggestive of inflammation or malignancy were not observed.  相似文献   
37.
Summary In an effort to achieve a simple and less invasive method for the treatment of chronic subdural haematoma, replacement of the haematoma with oxygen by percutaneous subdural tapping was employed in 36 patients. This study was conducted on 23 haematomas in 20 patients, whose computed tomography (CT) scans immediately following the treatment were available for evaluation, with particular regard to distinguishing between their findings and those seen with tension pneumocephalus. The CT features werde divided into two patterns according to the location of oxygen; a convexity type (19 haematomas) and an interhemispheric type (4 haematomas). Analysis of the CT appearances revealed the oxygen was exclusively confined to the haematoma cavity, distinguishing it from the findings in tension pneumocephalus. This observation indicates the safety of replacement of the haematoma with oxygen when combined with our percutaneuous subdural tapping technique which prevents lesions of the inner haematoma membrane.  相似文献   
38.
Effects of TPE on prevention of hepatic failure after massive hepatectomy were studied experimentally using dogs. A 70% or 85% hepatectomy (Hx) was performed two weeks after TPE. All of the 70%Hx groups with(+)/without(-) TPE were alive for over two weeks after hepatectomy. While all of the 85%Hx group without TPE died, eight of ten in the 85%Hx group with TPE survived. Without TPE, total bilirubin levels in sera were elevated markedly in the 85%Hx group and moderately in the 70%Hx group after hepatectomy. The levels of escaped enzymes in sera, such as GOT or GPT, were also elevated remarkably in the TPE(-) groups. Although the levels of these enzymes were also high in the 85%Hx.TPE(+) group, these values were as same as those of 70%Hx.TPE(-) group. In the 85%Hx.TPE(-) group, critical diminution of functional hepatic cell mass and severe portal hypertension occurred after hepatectomy and coagulopathy and death followed to these phenomena. TPE might prevent the onset of these critical phenomena, and diminish the damage caused by massive hepatectomy. These results suggest that TPE is useful for prevention of postoperative hepatic failure so that we could perform massive hepatectomy safely, and extend the operative indication.  相似文献   
39.
The effects of platelet-derived growth factor (PDGF) on phospholipase D (PLD) activity and deoxyribonucleic acid (DNA) synthesis in rat C6 glioma cells have been investigated. Pretreatment of serum-starved C6 cells with PDGF results in enhanced choline production and the phosphatidylethanol (PEt) formation in the presence of ethanol, indicating the activation of PLD acting on phosphatidylcholine (PC). The dose-response curve for choline generation and DNA synthesis were comparable. In addition, the effects of PDGF on both PEt formation and [3H]thymidine incorporation into acid-precipitable material was blocked by the potent protein kinase C (PKC) inhibitor 1-(5-isoquinolinesulphonyl)-2-methylpiperazine (H-7) but not by N-(2-guanidinoethyl)-5-isoquinolinesulphonamide (HA1004), a relatively weak inhibitor of PKC, suggesting that PDGF plays an important role as a positive regulator of glioma cell growth via a PLD-mediated mitogenic signal transduction cascades, which depends largely on the activation of PKC.  相似文献   
40.
N Ogura  Y Baba  I Sakai  K Taneichi  H Shibaki 《Ryūmachi》1992,32(5):508-14; discussion 512-3
We report a 28-year-old woman with systemic lupus erythematosus (SLE) who showed tubulo-interstitial nephritis (TIN) without any glomerular changes. In 1990, she was admitted to our hospital, complaining of anorexia, vomiting and persistent high fever. Laboratory findings showed proteinuria, pancytopenia, hypocomplementemia and positive for antinuclear antibody, anti-DNA antibody, anti-Sm antibody, anti-SSA antibody and anti-SSB antibody. We made a diagnosis of SLE. Furthermore, distal renal tubular acidosis and asteatosis cutis were revealed. The diagnosis of Sj?gren's syndrome was not made. We treated with high-dose prednisolone (60mg/day) and achieved improvement of symptoms and laboratory data. Open renal biopsy showed TIN without any glomerular changes. Predominant TIN is very rare in SLE. We discussed its pathogenesis and relation to the renal lesions of Sj?gren's syndrome.  相似文献   
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