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1.
OBJECTIVE: A joint study was undertaken by the Japanese Society of Renal Cancer to investigate the present status of partial nephrectomy in Japan and to speculate about what may be the indications for partial nephrectomy in patients with renal cell carcinoma. METHODS: Data were tabulated for 469 patients from participating medical institutions and various clinical factors were investigated with regard to disease progression (local recurrence and distant metastasis). RESULTS: Disease progression was observed in 21 patients (4.5%). No significant relation to disease progression was observed for sex, laterality, tumor histology, grade and tumor size. Although patients with solitary tumors displayed excellent prognosis irrespective of tumor diameter, patients with multiple tumors displayed a high likelihood of disease progression. Patients older than 77 years old and patients with imperative indication were found to have a poorer prognosis. CONCLUSION: In patients with solitary tumors, partial nephrectomy can be actively performed, even if the patient displays elective indications and the tumor is >4 cm in diameter. In patients displaying multiple tumors with imperative indications, the decision whether to perform partial nephrectomy should be made by the patients and their physicians after considering the impact on curability and the quality of life.  相似文献   
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Renal leiomyomas large enough to be clinically diagnosed are extremely rare. We review 30 cases of clinically diagnosed renal leiomyoma from the literature in Japan, including our 2 new cases. Case 1: In a 52-year-old man with no symptoms a renal mass was found accidentally on an ultrasonogram. CT scan showed a mass with a cystic area at the upper pole of the right kidney. Angiogram showed a hypovascular mass. Case 2: CT scan revealed a cystic mass and angiogram showed an avascular mass at the upper pole of the left kidney in a 19-year-old man having gross hematuria and left flank pain. Transperitoneal nephrectomy was done in both cases. Histologically each tumor was composed of monotonous proliferation of spindle shaped cells without atypia, which showed intense immunoreactivity for alpha-smooth muscle actin. The diagnosis of benign leiomyoma was made in each case. In a review of 30 cases, we found that renal leiomyomas occur most often in female (77%), between decades 2 and 5 of life (median: 46 years). On the angiogram it appears most often as an avascular or hypovascular mass. CT scan shows cystic or mixed solid/cystic or solid lesion, occasionally with calcification. Preoperative diagnosis is extremely difficult to be made. Histologically, fibroma, angiomyolipoma, congenital mesoblastic nephroma and leiomyosarcoma should be differentiated.  相似文献   
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Integrins are not involved in the process of human sperm-oolemmal fusion   总被引:3,自引:0,他引:3  
BACKGROUND: We investigated whether integrins are required forthe human sperm–oocyte binding and fusion processes. METHODS:The expression of several integrin subunits at the human oocyteplasma membrane was investigated using immunofluorescence microscopy,and the functional role of integrins expressed at the humanoocyte surface in sperm–oocyte interaction was studiedusing a zona-free human oocyte binding and fusion assay. A totalof 144 unfertilized oocytes were stained with anti-integrinantibodies and 147 zona-free unfertilized oocytes were inseminatedin the presence of various anti-integrin antibodies that wereexpressed in oocyte plasma membrane. RESULTS: The antibodiesof six integrin subunits (2, 3, 5, 6, V, M) and six integrinsubunits (1, 2, 3, 4, 5, 6) were bound to the surface of fixedunfertilized oocytes. In contrast, the presence of 1 and 4 subunitscould not be verified. The human sperm–oocyte bindingwas only partially inhibited by blocking antibodies of 2, 3,5, 6, V, M, 1, 2 and 3 with a maximum of 55% inhibition, butantibodies of 4, 5 and 6 showed no effect on sperm–oolemmalbinding. A similar reduction of the number of fused sperm wasobserved. However, the ratio of fused sperm to total sperm (boundand fused) was not impaired by all integrin antibodies, suggestingthat integrins had no role in the sperm–oolemmal fusionprocess. CONCLUSIONS: These results suggest that one of thebinding mechanisms can be inhibited by integrin antibodies butthat this mechanism does not play an essential role in the humansperm–oolemmal binding and fusion processes. The othermechanisms, insensitive to integrins, may involve both bindingand fusion processes in human oocytes.  相似文献   
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Spontaneous perforation of rectosigmoid colon is rare but usually results in severe peritonitis, with very high mortality. Two cases of spontaneous rectosigmoid perforations are reported here along with a brief literatures review.  相似文献   
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To search for the signaling events in colorectal carcinoma relevant to its tumorigenesis, we investigated the activity of mitogen-activated protein kinase (MAPK) in human colorectal carcinoma tissues and paired normal tissues. Of 64 cases examined, approximately 75% (48 cases) showed tumor-specific activation of MAPK by in situ kinase renaturation assay, as well as in vitro kinase assay with immunoprecipitated MAPK. In addition, tumor-specific activation of MAPK was associated with the activation of MAPK kinase in the cases we examined. However, no clear correlation of MAPK activation with lymph node involvement, metastatic rate, stage, histological classification, age or sex was observed. These results suggest that the MAPK pathway is involved in colorectal tumor development, but its activation alone is not sufficient for malignant conversion. In contrast to colorectal carcinoma, gastric carcinoma tissues showed a lower rate of MAPK activation, suggesting that the signaling pathway activated in colorectal carcinoma tissues may differ in part from that of gastric carcinoma.  相似文献   
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Effects of portal-systemic shunt following 90% partial hepatectomy in rats   总被引:5,自引:0,他引:5  
We studied the effects of portal-systemic shunt after massive hepatectomy. Male Wistar rats were divided into two groups: one group underwent laparotomy alone (C group) and in the other group a portal-systemic shunt was placed through laparotomy (S group). After 90% hepatectomy was performed, 3-day and 1-week survival rates and histopathology were examined, and hepatic hemodynamics during the early stage after hepatectomy were measured using dye-containing microspheres. The 3-day survival rate in the S group was significantly higher, and the 1-week survival rate was slightly higher, than those in C group. Sinusoidal dilation 7 days after hepatectomy in the S group was significantly milder than that in the C group. Fatty degeneration of hepatocytes in the S group was significantly milder than that in the C group. With respect to hepatic hemodynamics during the early stage after hepatectomy, the rate of shunt (26.3%) in the S group was significantly higher than that (9.5%) in the C group. Portal pressure, total hepatic blood flow, and total hepatic blood flow per gram of liver in the S group were significantly lower than those in the C group. These results suggest that approximately 26% shunt after 90% hepatectomy in rats increases the early survival rate and improves histological changes in surviving rats 7 days after resection.  相似文献   
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Neovascularization of the outer membrane plays a critical role in the development and enlargement of chronic subdural hematomas (CSHs) and vascular endothelial growth factor (VEGF) may promote their progression. However, the precise mechanisms remain to be determined. We focused on the signaling pathway upstream of VEGF, transforming growth factor β (TGF-β), and activin receptor-like kinase 1 (ALK-1) to identify the mechanisms underlying the neovascularization of the outer membrane of CSH. Retrospective comparative study was conducted on 15 consecutive patients diagnosed as CSH with burr-hole drainage. Dura and the outer membrane were collected. We immunohistochemically examined the expression of VEGF, integrin-α, TGF-β, and ALK-1 on the outer membrane and dura of CSH and compared our findings with control samples and the signal intensity of hematomas on computed tomography (CT) scans. VEGF and integrin-α expression was markedly up-regulated in both the dura and outer membrane of CSH, the expression of TGF-β and ALK-1 in the dura was slightly increased in the dura and markedly up-regulated in the outer membrane. There was no significant correlation between their expression and CT density. Here we first report the expression of TGF-β and ALK-1 in the outer membrane and dura mater of CSH. We suggest that the TGF-β–ALK-1 pathway and VEGF affect neovascularization and the progression of CSH.  相似文献   
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A 73-year-old woman was admitted with consciousness disturbance following a fever. Abdominal computed tomography revealed a large liver abscess with which the presence of Desulfovibrio desulfuricans and Escherichia coli was confirmed by thorough blood and abscess content culture. Empiric meropenem treatment was switched to cefoperazone/sulbactam, followed by ampicillin/sulbactam based on susceptibility testing. Desulfovibrio desulfuricans is a common bacterium that rarely causes liver abscess and may be overlooked during co-infection due to overgrowth of the accompanying bacteria. Clinicians should bear Desulfovibrio desulfuricans in mind and select the appropriate antibiotics according to susceptibility testing when anaerobic bacteria are detected in a liver abscess.  相似文献   
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