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1.
Endoscopic nasobiliary drainage (ENBD) is a well established mode of biliary decompression. Although ENBD is certainly an uncomfortable procedure with the potential risk of spontaneous dislocation or removal of the drainage catheter by disoriented patients, it has several advantages over endoscopic biliary drainage (EBD) using an indwelling stent. The current indications for ENBD are: (i) temporary drainage to treat obstructive jaundice and cholangitis caused by malignant or benign biliary stricture; (ii) urgent drainage to treat suppurative cholangitis primarily caused by common bile duct stones; (iii) temporary drainage after stone removal in patients with suspected incomplete clearance and/or with cholangitis; and (iv) biliary leaks that occur primarily after surgery, as well as other indications. Different types of nasobiliary catheters are currently available that have been designed with various diameters, shapes, and materials. However, the current catheters are not considered by most endoscopists to be sufficient. Further improvements are needed to achieve better drainage and better maneuverability.  相似文献   
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OBJECTIVE: To assess alterations in brain metabolites of patients with Pelizaeus-Merzbacher disease (PMD) with the proteolipid protein gene 1 (PLP1) duplications using quantitative proton MRS. METHODS: Five unrelated male Japanese patients with PMD with PLP1 duplications were analyzed using automated proton brain examination with the point resolved spectroscopy technique (repetition and echo time of 5,000 and 30 msec). Localized spectra in the posterior portion of the centrum semiovale were acquired, and absolute metabolite concentrations were calculated using the LCModel. RESULTS: Absolute concentrations of N-acetylaspartate (NAA), creatine (Cr), and myoinositol (MI) were increased by 16% (p < 0.01), 43% (p < 0.001), and 31% (p < 0.01) in patients with PMD as compared with age-matched controls. There was no statistical difference in choline concentration. CONCLUSION: The increased concentration of NAA, which could not be detected by previous relative quantitation methods, suggests two possibilities: axonal involvement secondary to dysmyelination, or increased cell population of oligodendrocyte progenitors. Elevated Cr and MI concentrations may reflect the reactive astrocytic gliosis. Our study thus emphasizes the importance of absolute quantitation of metabolites to investigate the disease mechanism of the dysmyelinating disorders of the CNS.  相似文献   
3.
Aggregation and secretion of washed platelets from stroke-prone spontaneously hypertensive rats(SHRSP) were greatly reduced by the development of hypertension in comparison with age-matched normotensive WKY platelets. In an attempt to clarify the mechanism of the defective functions, Ca2+ transport in platelets from SHRSP and WKY were studied. Changes of cytoplasmic free Ca2+ concentration ([Ca2+]i) were examined by using Quin 2. [Ca2+]i increase in response to thrombin(0.028 - 0.11 U/ml) was significantly delayed in SHRSP platelets compared with that of age-matched WKY platelets. The time(sec) to peak in [Ca2+]i was about two times longer in SHRSP platelets than in WKY platelets. [Ca2+]i levels at resting state were significantly lower in SHRSP platelets while there was no difference in maximal [Ca2+]i level in response to thrombin (0.031 - 0.125 U/ml) between the two strains. In addition thrombin-induced 45Ca2+ uptake was significantly delayed in SHRSP platelets. This delay of [Ca2+]i increase following thrombin stimulation might be associated with the hypofunctions of SHRSP platelets.  相似文献   
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We report 51- and 43-year-old Japanese female patients with systemic lupus erythematosus (SLE) associated with subarachnoid hemorrhage (SAH) due to rupture of intracranial saccular aneurysms. We also review the literature of Japanese SLE patients with SAH. SAH in Japanese SLE patients is more frequent than in patients from Western countries, has different features from the general population, and can occur regardless of SLE disease activity. Clinicians must pay attention to SAH in all SLE patients.  相似文献   
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Big mitogen-activated protein kinase 1 (BMK1), also known as extracellular signal-regulated kinase 5 (ERK5), is a newly identified member of the mitogen-activated protein (MAP) kinase family. Recently, several studies have suggested that BMK1 plays an important role in the pathogenesis of cardiovascular disease. To clarify the pathophysiological significance of BMK1 in the process of vascular remodeling, we explored the molecular mechanisms of BMK1 activation in vascular smooth muscle cells (VSMCs). From the results of co-immunoprecipitation and immunoblotting analyses, it was found that platelet-derived growth factor (PDGF), a known potent mitogen, activated BMK1 and triggered the Gab1-SHP-2 interaction in rat aortic smooth muscle cells (RASMCs). The abrogation of SHP-2 phosphatase activity by transfection of the SHP-2-C/S mutant suppressed PDGF-stimulated BMK1 activation. Infection with an adenoviral vector expressing dominant-negative MEK5alpha, which can suppress PDGF-stimulated BMK1 activation to the control level, inhibited PDGF-induced RASMC migration. Moreover, we observed an increase of BMK1 activation in injured mouse femoral arteries. From these findings, it is suggested that BMK1 activation leads to VSMC migration induced by PDGF via Gab1-SHP-2 interaction, and that BMK1-mediated VSMC migration may play a role in the pathogenesis of vascular remodeling.  相似文献   
9.
OBJECTIVES: To determine the value of the loss of expression of E-cadherin and cadherin associated molecules as useful markers for both prognosis and chemosensitivity in bladder cancer patients who have undergone radical cystectomy. PATIENTS AND METHODS: In 55 paraffin embedded specimens of radical cystectomy at our hospital from 1982 to 2000, the expression of E-cadherin, alpha-, beta- and gamma-catenin was examined by immunohistochemical staining. To evaluate the prognostic significance of these molecules, Kaplan-Meier survival curves were constructed and a statistical analysis was calculated by a log-rank test. A multivariate test (tumor stage, tumor grade, lymph node metastasis, configuration, the expression of E-cadherin, alpha-, beta- and gamma-catenin) was performed to detect prognostic markers. RESULTS: Normal expression was found in 33 cases (60.0%) for E-cadherin, 29 (52.7%) for alpha-catenin, 31 cases (56.4%) for beta-catenin, and 31 cases (56.4%) for gamma-catenin. The expression patterns for E-cadherin, alpha-, beta- and gamma-catenin were significantly correlated with each other (P < 0.01). Survival analysis showed a significant difference between normal and aberrant expression in each staining. A multivariate analysis revealed that the expression of alpha- catenin was an independent prognostic factor (P = 0.0191). In 23 patients that received adjuvant chemotherapy, there was a significant difference in survival between the normal and aberrant expression of alpha-catenin, but not other molecules. CONCLUSION: Alpha-catenin may not only be a good prognostic marker, but also one of key molecules that determine the chemosensitivities in patients with invasive bladder cancer.  相似文献   
10.
A 33-year-old man with a left testicular tumor was referred to Shinshu University Hospital for advanced therapy. Radiographic imaging revealed multiple metastases in the retroperitoneal lymph nodes (RPLN) and bilateral lungs, as well as tumor thrombus that extended from the left renal vein to the inferior vena cava (IVC) adjacent to the right atrium. After orchidectomy, a diagnosis of embryonal carcinoma was made with a clinical stage of T1N2M1bS3, which has a poor prognosis, based on the International Germ Cell Cancer Collaborative Group consensus. After eight courses of chemotherapy, the patient's tumor markers normalized and the lung metastases disappeared, but the RPLN and tumor thrombus remained. Retroperitoneal lymph node dissection and thrombectomy were performed using a veno-venous bypass (VVB). The pathological examination of the thrombus revealed a mature teratoma. The patient has been disease-free since surgery.  相似文献   
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