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91.
92.
Comparative studies of pancreatic enzymes carbohydrate antigen 19-9 (CA 19-9) and carcinoembryonic antigen (CEA) were performed in various pancreatic disease. In acute pancreatitis as well as during acute exacerbation of chronic pancreatitis, all pancreatic enzymes were abnormally high. In chronic pancreatitis, they did not have any diagnostic sensitivity for pancreatic insufficiency. In pancreatic carcinoma, serum elastase levels may have a diagnostic value compared with other pancreatic enzymes. In studies of CEA and CA 19-9, both tumor markers were within normal range in benign pancreatitis but 27.7% of CEA and 30.7% of CA 19-9 in acute pancreatitis were above normal. In pancreatic carcinoma, although most of these patients had advanced disease, both tumor markers were extremely high and 61% for CEA and 71% for CA 19-9 were above normal. In patients with resected pancreatic carcinoma, serum CEA was slightly higher than normal CA 19-9 was much higher than normal. The sensitivity of CEA and CA 19-9 in this group were 33 and 77.7%, respectively. The results indicate that the CA 19-9 assay is a useful adjunct in the diagnosis of pancreatic carcinoma, possibly in the resectable stage especially combined measurement of serum elastase and CEA.  相似文献   
93.

Background

Glomerular hypertension aggravates glomerular sclerosis by inducing growth factors, e.g., transforming growth factor-β (TGF-β) to mesangial matrix expansion. Smads are intracellular proteins that transmit signals from TGF-β to nucleus, and Smads are also negatively regulated by inhibitory Smads (I-Smads), Smad6 and Smad7. However, little is known about the role of I-Smads in glomerular hypertension. We studied I-Smad expression in cultured mesangial cells subjected to mechanical stretch as an in vitro model of glomerular hypertension.

Methods

Rat mesangial cells were cultured under cyclic mechanical stretch conditions using the Flexercell Strain Unit. Phosphorylated Smad1 and Smad2 were determined by Western blots. The expression of Smad6 and Smad7 mRNAs was determined by Northern blots. Stretch-mediated I-Smad mRNAs of cells pre-treated with MAPK-ERK kinase inhibitor, U0126, were also determined. Localization of phospho-Smad1, Smad6 and Smad7 proteins in the glomerulus of Dahl salt-sensitive rats was determined by immunohistochemistry.

Results

Stretch stress increased phospho-Smad1 levels, and significantly decreased Smad6 mRNA to 32?% of control, and increased Smad7 mRNA to 136?% of control. U0126 significantly attenuated stretch-mediated decreases in Smad6 mRNA, but had no effect on stretch-mediated increases in Smad7 mRNA. Phospho-Smad1, Smad6 and Smad7 proteins were localized in podocytes and mesangial cells of Dahl rats.

Conclusion

Mechanical stretch increases phospho-Smad1 levels and down-regulates Smad6 mRNA expression in mesangial cells. Stretch-mediated down-regulation of Smad6 is partially involved in ERK1/2 activation. These results indicate that glomerular hypertension might augment Smad1 signaling with concomitant attenuation of Smad6-mediated negative feedback.  相似文献   
94.
BACKGROUND: Carbon dioxide is an important vasodilator of cerebral blood vessels. Cerebral vasodilation mediated by adenosine triphosphate (ATP)-sensitive K+ channels has not been demonstrated in precapillary microvessel levels. Therefore, the current study was designed to examine whether ATP-sensitive K+ channels play a role in vasodilation induced by mild hypercapnia in precapillary arterioles of the rat cerebral cortex. METHODS: Brain slices from rat cerebral cortex were prepared and superfused with artificial cerebrospinal fluid, including normal (Pco2 = 40 mmHg; pH = 7.4), hypercapnic (Pco2 = 50 mmHg; pH = 7.3), and hypercapnic normal pH (Pco2 = 50 mmHg; pH = 7.4) solutions. The ID of a cerebral parenchymal arteriole (5-9.5 microm) was monitored using computerized videomicroscopy. RESULTS: During contraction to prostaglandin F2alpha (5 x 10(-7) m), hypercapnia, but not hypercapnia under normal pH, induced marked vasodilation, which was completely abolished by the selective ATP-sensitive K+ channel antagonist glibenclamide (5 x 10(-6) m). However, the selective Ca2+-dependent K+ channel antagonist iberiotoxin (10(-7) m) as well as the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (10(-4) m) did not alter vasodilation. A selective ATP-sensitive K+ channel opener, levcromakalim (3 x 10(-8) to 3 x 10(-7) m), induced vasodilation, whereas this vasodilation was abolished by glibenclamide. CONCLUSION: These results suggest that in parenchymal microvessels of the rat cerebral cortex, decreased pH corresponding with hypercapnia, but not hypercapnia itself, contributes to cerebral vasodilation produced by carbon dioxide and that ATP-sensitive K+ channels play a major role in vasodilator responses produced by mild hypercapnia.  相似文献   
95.
Background: Carbon dioxide is an important vasodilator of cerebral blood vessels. Cerebral vasodilation mediated by adenosine triphosphate (ATP)-sensitive K+ channels has not been demonstrated in precapillary microvessel levels. Therefore, the current study was designed to examine whether ATP-sensitive K+ channels play a role in vasodilation induced by mild hypercapnia in precapillary arterioles of the rat cerebral cortex.

Methods: Brain slices from rat cerebral cortex were prepared and superfused with artificial cerebrospinal fluid, including normal (Pco2 = 40 mmHg; pH = 7.4), hypercapnic (Pco2 = 50 mmHg; pH = 7.3), and hypercapnic normal pH (Pco2 = 50 mmHg; pH = 7.4) solutions. The ID of a cerebral parenchymal arteriole (5-9.5 [mu]m) was monitored using computerized videomicroscopy.

Results: During contraction to prostaglandin F2[alpha] (5 x 10-7 m), hypercapnia, but not hypercapnia under normal pH, induced marked vasodilation, which was completely abolished by the selective ATP-sensitive K+ channel antagonist glibenclamide (5 x 10-6 m). However, the selective Ca2+-dependent K+ channel antagonist iberiotoxin (10-7 m) as well as the nitric oxide synthase inhibitor NG-nitro-l-arginine methyl ester (10-4 m) did not alter vasodilation. A selective ATP-sensitive K+ channel opener, levcromakalim (3 x 10-8 to 3 x 10-7 m), induced vasodilation, whereas this vasodilation was abolished by glibenclamide.  相似文献   

96.
Purpose: The purpose of this paper is to describe the ultrasonographic findings of the patent processus vaginalis (PPV) in neonates.Methods: The patency of the processus vaginalis was examined by ultrasonography in 117 neonates. The ultrasonographic findings, with increment and decrement of the intraabdominal pressure, were categorized into 6 types as follows: type I, the intraabdominal organ is observed; type II, cystic PPV; type III, the PPV is widened with abdominal pressure increment, the length is ≥20 mm; type IV, the PPV contains moving fluid without PPV widening; type V, the PPV is widened with abdominal pressure increment, the length is less than 20 mm; type VI, others. The authors we regarded types I to IV as PPV with inguinal hernia.Results: Twenty-two of 40 neonates with a birth weight under 2,500 g had PPV, including 8 with type I. Twenty of 37 premature neonates 22 to 37 gestational weeks had PPV, including 8 with type I. Eighty-one percent (13 of 16) of PPV in low-birth-weight neonates and 91% (10 of 11) in premature neonates closed spontaneously. The median ages at the time of spontaneous regression of PPV were 242 days in low birth weight neonates and 262 days in premature neonates.Conclusions: Most premature or low-birth-weight neonates with PPV regress spontaneously. The inguinal hernia in neonates (especially in premature or low-birth-weight neonates) should be observed until at least 9 months of age without attempting hernia repair.  相似文献   
97.
A 29-year-old woman with symptoms suggestive of trigeminal neuralgia is presented. Because of her age, an intracranial tumor was suspected, but images of a brain computerized tomography scan revealed nothing in particular. A magnetic resonance imaging was scheduled 2 weeks later. However, as the pain increased and occurred more frequently, the patient returned to the hospital 2 days later. After a stellate ganglion block with transient nausea and dizziness, the pain was noticeably relieved. Using magnetic resonance scanning, a tumor in the cerebellopontine angle was discovered, and at surgical resection was diagnosed as an epidermoid tumor. Stellate ganglion block may provide pain relief to some patients who are suspected to have symptomatic trigeminal neuralgia.  相似文献   
98.
Living donor liver transplantation (LDLT) for patients with portal vein thrombosis (PVT) involves technical difficulty. The aim of this research was to analyze their preoperative diagnosis of PVT, operative procedures, and postoperative courses of patients with preoperative PVT. Thirty-nine patients of 404 adult patients (9.7%) undergoing LDLT in our hospital from 1996 June to 2004 December had PVT at their transplantation. Twenty-nine patients had intractable ascites, 21 had gastrointestinal bleeding, and 18 had encephalopathy. The thrombus was located in the portal trunk in 23, in the portal trunk and superior mesenteric vein (SMV) in 7, and developed into the SMV and the splenic vein in 8. The occlusive grade was partial in 29, and complete in 10 patients. The thrombus was removed by a simple technique, and eversion and/or incision technique, or total removal of the portal vein (PV). The PV was reconstructed with the thrombectomized native PV, with an interposed vein graft, or porto-caval hemitransposition. Advanced PVT had a significant impact on blood loss and hospital mortality. Three out of 10 patients with residual PVT required radiological and/or surgical intervention after transplantation. In conclusion, thorough planning is essential for a successful LDLT outcome for patients with preexisting PVT.  相似文献   
99.

Background

Although many risk factors are reported about graft rejection after heart transplantation (HTx), the effect of HLA mismatch (MM) still remains unknown, especially in the Japanese population. The aim of the present study was to investigate the influence of HLA MM on graft rejection among HTx recipients in Japan.

Methods

We retrospectively investigated the association of the number of HLA MM including class I (A, B) and class II (DR) (for each locus MM: 0 to 2, total MM: 0 to 6) and the incidence of moderate to severe acute cellular rejection (ACR) confirmed by endomyocardial biopsy (International Society for Heart and Lung Transplantation grade ≥ 3A/2R) within 1 year after HTx.

Results

Between 2007 and 2014, we had 49 HTx cases in our institute. After excluding those with insufficient data and positive donor-specific antigen, finally 35 patients were enrolled. Moderate to severe ACR was observed in 16 (45.7%) patients. The number of HLA-DR MM was significantly associated with the development of ACR (ACR+: 1.50 ± 0.63, ACR?: 1.11 ± 0.46, P = .029). From univariate analysis, DR MM = 2 was the only independent risk factor for ACR episodes (P = .017). The frequency of ACR within 1 year was significantly higher in those with DR MM = 2 (DR MM = 0 to 1: 0.3 ± 0.47, DR MM = 2: 1.17 ± 1.34 times, P = .007).

Conclusions

The number of HLA-DR MMs was associated with the development and recurrence of ACR episodes among HTx recipients within 1 year after transplantation in Japanese population.  相似文献   
100.
Background and aims  Bleeding from the hepatic vein is closely related to central venous pressure (CVP). To evaluate the effect of low central venous pressure during a hepatectomy, the infrahepatic inferior vena cava (IVC) was half clamped. Patients and methods  Between 2006 and 2007, 20 patients undergoing major hepatectomy with the IVC half clamping (half-clamping group) were compared with 58 patients undergoing hepatectomy without IVC half clamping between 2003 and 2005 (control group). The types of liver resection, amount of blood loss during the hepatectomy, volume of blood transfusion, length of hospital stay, and complications were compared between the two groups. Results  In the half-clamping group, blood loss was decreased in comparison to the control group (p = 0.041) and the suprahepatic CVP was low (2.4 ± 1.8 mmHg; p = 0.0002). The diameter at the root of the right hepatic vein was reduced in comparison to before clamping (5.8 ± 1.6 mm; p < 0.001). There were no complications of half clamping on any hemodynamic and blood electrolytic parameters. Conclusion  Using the half clamping technique of the IVC, intra-operative CVP was maintained below 3 mmHg without any side effects, and the low CVP significantly reduced the bleeding from hepatic veins during a major hepatectomy.  相似文献   
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