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991.
PURPOSE: The SRD5A2 gene codes the steroid 5-reductase type II, a critical mediator of androgen action, and the V89L and A49T polymorphisms of this gene may be associated with a distinct enzyme activity. We explored the association among these polymorphisms and the risk of prostate cancer or benign prostatic hyperplasia (BPH) in a Japanese population. MATERIALS AND METHODS: This study included 302 patients with prostate cancer, 228 with BPH and 243 male controls. V89L and A49T polymorphisms were analyzed by the polymerase chain reaction restriction fragment length polymorphism method. Genotypes were evaluated by electrophoresis on agarose gel. RESULTS: For the V89L polymorphism there were no significant differences in genotype frequencies in patients with prostate cancer and controls (p = 0.071) or in patients with BPH and male controls (p = 0.219). However, males with the VV or VL genotype were at significantly increased risk for prostate cancer compared with those with the LL genotype (adjusted OR 1.69, 95% CI 1.07 to 2.65, p = 0.024). The risk of BPH in males with the VV or VL genotype was not significantly elevated in comparison with those with the LL genotype (adjusted OR 1.37, 95% CI 0.85 to 2.20, p = 0.194). The V89L variant was not associated with the grade or stage of prostate cancer, or with patient age. For the A49T polymorphism all subjects had the AA genotype. CONCLUSIONS: The V allele of the V89L polymorphism in the SRD5A2 gene may dominantly increase the risk of prostate cancer.  相似文献   
992.
Diffusion-weighted MR imaging was performed in 5 control subjects and 8 patients with Alzheimer's disease(AD). The mean values of fractional anisotropy(FA) were calculated in the genu and splenium of the corpus callosum, and anterior and posterior cerebral white matter. The FA value of the posterior white matter in patients with AD was significantly lower than that of controls. Fractional anisotropy may be useful in the diagnosis of AD.  相似文献   
993.
BACKGROUND: Intracranial MR venography is useful for the diagnosis of dural sinus thrombosis and the preoperative assessment of sinus patency encased by tumors. Recently, contrast-enhanced MR venography has been applied for suspected dural sinus occlusion in a shorter time. However, it has some disadvantage for the evaluation of hypervascularized enhancing thrombus mimicking flow in chronic sinus thrombosis. So far, we have evaluated optimal imaging technique and slice orientation and have shown that sagittal three-dimensional (3D) -phase contrast (PC) imaging is the most suitable for the non-contrast intracranial MR venography. PURPOSE:To assess the optimal presaturation pulse (SAT) and velocity encoding (VENC) for the non-contrast intracranial 3D-PC MR venography. METHODS AND MATERIALS: Firstly, we performed phantom experiment to assess the best SAT thickness using arterial presaturation. Second, MR imaging was performed in 7 healthy volunteers to measure the dural sinus flow velocity using a 1.5 T MR. Third, 3D-PC MR venography was performed with a VENC settings at 10, 15, 20 and 30 cm/sec for healthy volunteers. All data were displayed as maximum intensity projection images and three neuroradiologists assessed the visibility of the dural sinuses and the cortical vein. RESULTS: The mean flow velocity of the dural sinuses was 6.3 cm/sec. The thickness of the best SAT was 100 mm. In the assessment of the visibility of the 3D-PC images, dural sinuses were adequately visualized at a VENC of 15 cm/sec. CONCLUSIONS: Non-contrast intracranial 3D-PC MR venography was optimized at 100mm thickness of SAT and a VENC of 15 cm/sec.  相似文献   
994.
The INNOVA 2000, an all-digital cardiovascular X-ray system with flat panel detector, is equipped with a monitoring function that makes it possible to track a patient's absorbed dose by displaying the real-time presumed absorbed dose. We verified this dose monitoring system and evaluated how it is affected by various parameters. We also compared the INNOVA 2000 to a conventional machine, the Advantx LC. The average absorbed dose of the INNOVA 2000 was 1,066 mGy, while that of the Advantx LC was calculated to be 2,028 mGy. Dose reduction with the INNOVA 2000 was 76% at Low mode and 52% even at Normal mode. The INNOVA provides an advantage in lowering absorbed dose, even considering that it has a rectangular image intensifier (I.I.) versus the Advantx LC's round I.I. This comparison was made by cine and digital angiography.  相似文献   
995.
Okada S  Shikata K  Matsuda M  Ogawa D  Usui H  Kido Y  Nagase R  Wada J  Shikata Y  Makino H 《Diabetes》2003,52(10):2586-2593
Diabetic nephropathy is a leading cause of end-stage renal failure. Several mechanisms, including activation of protein kinase C, advanced glycation end products, and overexpression of transforming growth factor (TGF)-beta, are believed to be involved in the pathogenesis of diabetic nephropathy. However, the significance of inflammatory processes in the pathogenesis of diabetic microvascular complications is poorly understood. Accumulation of macrophages and overexpression of leukocyte adhesion molecules and chemokines are prominent in diabetic human kidney tissues. We previously demonstrated that intercellular adhesion molecule (ICAM)-1 mediates macrophage infiltration into the diabetic kidney. In the present study, to investigate the role of ICAM-1 in diabetic nephropathy, we induced diabetes in ICAM-1-deficient (ICAM-1(-/-)) mice and ICAM-1(+/+) mice with streptozotocin and examined the renal pathology over a period of 6 months. The infiltration of macrophages was markedly suppressed in diabetic ICAM-1(-/-) mice compared with that of ICAM-1(+/+) mice. Urinary albumin excretion, glomerular hypertrophy, and mesangial matrix expansion were significantly lower in diabetic ICAM-1(-/-) mice than in diabetic ICAM-1(+/+) mice. Moreover, expressions of TGF-beta and type IV collagen in glomeruli were also suppressed in diabetic ICAM-1(-/-) mice. These results suggest that ICAM-1 is critically involved in the pathogenesis of diabetic nephropathy.  相似文献   
996.
A 29-year-old male with bladder cancer was referred to our hospital. Histological examination of transurethral biopsy showed transitional cell carcinoma with invasion into prostate (T4aN0M0, grade 3). Nerve-sparing radical cystectomy with ileal neobladder reconstruction was performed after 3 courses of neoadjuvant chemotherapy with Methotrexate, Epirubicin and Cisplatin. Continence and erectile function were preserved and no recurrence has been observed for 18 months after the operation. This is the sixth case of an invasive bladder cancer in Japanese patients under 30 years old.  相似文献   
997.
We report two cases of XX male with chief complaints of infertility. Physical examination of both patients aged 42 and 29 demonstrated normal male habitus except for small testes. Semen analyses demonstrated no spermatozoa. Endocrinological examinations showed hypergonadotrophic hypogonadism. Vesiculograms demonstrated normal seminal tracts. Histological examination of their testes did not reveal germ cells; one case lacked seminiferous tubules and there was hyalinization in the seminiferous tubule in another case. Chromosomal analyses of peripheral blood demonstrated 46,XX. The sex-determining region Y gene was positive and DAZ (deleted in azoospermia) gene was negative in both cases.  相似文献   
998.
We experienced a post-radiation therapy patient who had a narrow trachea, and presented with unexpected difficulty for intubation. His trachea was narrowest at 2 cm below the glottis. The fiberscope barely could pass the narrowest part of the trachea. We speculate that the radiation therapy induced his tracheal constriction. Careful attention is necessary when examining the post-radiation therapy patients. Multiple cervical radiographs are necessary in such a case.  相似文献   
999.
We present 2 cases of Scimitar syndrome with lung sequestration, 1 of which is infant case and the other is adult. A 3-month-old baby was transferred to our hospital because of severe heart failure. Cardiac ultrasonography and angiography revealed atrial septal defect and lung sequestration. Because of critical condition, she underwent emergency operation. After the operation of abnormal lung resection, her general condition improved. We emphasize that the prognosis is influenced by operation timing. A 20-year-old female was admitted for atrial septal defect. We diagnosed Scimitar syndrome and lung sequestration as the result of close examinations. We carried out definitive operations of the closure of atrial septal defect, the correction of partially anomalous pulmonary venous return and the resection of malformed lung. This adult case is popular one of Scimitar syndrome.  相似文献   
1000.
We experienced a rare case of left ventricular aneurysm (LVA) and ventricular septal perforation (VSP) with normal coronary arteries, and had a good outcome by undergoing Dor procedure and direct closure of VSP individually. A 68-year-old female was printed out cardiac systolic murmur. Echocardiogram revealed LVA and VSP, but coronary arteriogram showed no significant stenosis. The apex was incised longitudinally, lateral and parallel to the interventricular groove. VSP was directly closed by 2 pieces of 3-0 polypropylene suture with felt strip. Purse-string stitch with 3-0 polyester suture around the transitional zone between fibrotic tissue and viable tissue was secured to firm fibrous tissue. The residual orifice was closed with an elliptical composite patch of equine pericardial patch and polyester velour with 3-0 polypropylene suture. We considered based on the operative finding that myocardial infarction (MI) led to LVA and VSP. Coronary thrombosis rather than coronary spasm may have provoked MI because spasm provocative test was negative.  相似文献   
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