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991.
992.
OBJECTIVE: This study was performed to examine the role of the endothelial constitutive NO synthase (ecNOS) gene in patients with abdominal aortic aneurysm (AAA). METHODS: We determined the distributions of polymorphism in intron 4 of the ecNOS (ecNOS4) gene, amplified by polymerase chain reaction, and compared the allele frequencies between subjects with abdominal aortic aneurysms (AAAs) and healthy individuals. PATIENTS: Fifty-eight patients with AAAs and 410 race-matched healthy controls were studied. RESULTS: Two alleles of the ecNOS4 gene, containing 4 (a-allele) and 5 (b-allele) repeats, were identified. We found that the a-allele frequency of this gene was significantly higher in the surgical than in the non-surgical group. CONCLUSION: The results of this study suggest that the a-allele of the ecNOS4 gene is indicative of the need for surgery for AAA. Analysis of the alleles of the ecNOS4 gene polymorphism could provide useful information concerning the clinical course of AAA progression.  相似文献   
993.
The asialoglycoprotein receptor (ASGPR) is abundantly expressed on the sinusoidal surfaces of hepatocytes. We aimed to clarify the clinical significance of the regional distribution of ASGPRs in the human liver, especially in chronic viral hepatitis. Eighteen volunteers, 34 patients with chronic hepatitis, and 33 patients with cirrhosis (11/Child-Pugh A, 11/Child-Pugh B, 11/Child-Pugh C) were studied using a newly developed, conventional technetium-99m-diethylenetriaminepentaacetic acid-galactosyl human serum albumin ((99m)Tc-GSA), single photon emission computed tomography (SPECT) method. Using Cantlie's line as a guide, ASGPR dynamics were analyzed separately in the right and left lobes, as well as in the whole liver, using novel indices (the liver uptake ratio [LUR] and the liver uptake density [LUD], which reflect the amount and density of ASGPRs in the liver, respectively). Mean LUR and LUD values for the whole liver and the right and left lobes decreased with increasing progression of chronic viral hepatitis. The LUR for the whole liver correlated well with parameters measuring the hepatic functional reserve and the platelet count. The right LUR correlated particularly well with conventional liver function tests, and comparison of the right LUD with histologic findings showed that it was a good indicator of periportal and/or bridging necrosis and fibrosis. In conclusion, our (99m)Tc-GSA SPECT method was clinically useful in evaluating regional hepatic function and the progression of chronic viral hepatitis using dynamic changes in ASGPRs.  相似文献   
994.
Serum total T4 (T4), total T3 (T3), free T4 (FT4), free T3 (FT3), and T4-binding globulin concentrations and T3 resin uptake values were measured in 17 women with thyrotoxicosis due to painless thyroiditis (PT) and compared with the same parameters in 17 women with thyrotoxicosis due to Graves' disease (GD) with similar serum T4 levels. The mean serum T3 resin uptake value and T3, FT4, and FT3 concentrations in the PT patients were significantly lower than those in the GD patients. The mean serum T4-binding globulin concentration [20.2 +/- 4.2 (+/- SD) microgram/mL] in patients with PT did not differ significantly from those in patients with GD (18.0 +/- 2.6 micrograms/mL) and normal euthyroid women (21.9 +/- 4.0 micrograms/mL). The serum T3 to T4 (nanogram per microgram) ratio was higher than 20 in 14 GD patients, but lower than 20 in all patients with PT, whereas the individual serum FT3 to FT4 ratio values considerably overlapped in the 2 groups. In patients with PT, FT4 correlated well with T4 at various times during the clinical course. These findings indicate that the elevation in serum FT4 in patients with PT is mostly due to the increase in circulating T4 levels, whereas GD patients also have some diminution in T4 binding. The serum T3 to T4 ratio, but not the FT3 to FT4 ratio, may be helpful for differentiation between the two diseases.  相似文献   
995.
996.
997.
We reported five cases of listeriosis (sepsis and meningitis) in the elderly in our hospital during the last 4 years, where no cases of listeriosis had been found. These 5 cases had diabetes mellitus, lung cancer, chronic respiratory failure, gastric ulcer and aplastic anemia respectively as their underlying diseases. At the onset of listeriosis, 3 cases received corticosteroid and 3 cases received H2-blocker. 2 patients were cured and 3 patients died. Three autopsy cases had meningitis or meningoencephalitis and 2 cases of these autopsy cases had granulomatous changes in these spleens. In serotypes of Listeria monocytogenes (L. monocytogenes), 4 cases were 4b and 1 cases was 1b. All 5 strains were resistant to 3rd generation cephems. Wide uses of 3rd generation cephems and H2-blocker may be one of the reasons for the recent increase of listeriosis. Ingestion of contaminated food is the pathogenetic mechanism for initiating L. monocytogenes infections. And following the change of eating habits and the increase of imported foods, food-born listeriosis may increase. We suppose the increase of L. monocytogenes infections and must give attention to L. monocytogenes infections.  相似文献   
998.
999.
The importance of the cell cycle in proliferating cells is well known, but little is known about the role of cell cycle regulatory proteins in cardiac myocytes, which are fully differentiated cells. The present study determined, in vitro, the effect of angiotensin II (Ang II) treatment of neonatal rat cardiac myocytes on protein levels of cyclins and retinoblastoma gene product (pRb) phosphorylation. The role of G1 cyclin/cdk in Ang II-induced cardiac myocyte hypertrophy by overexpressing cdk inhibitor p21Cip1/Waf1 or p16INK4a was also examined using recombinant adenoviral vectors encoding these genes. Western blot analysis revealed that Ang II stimulated cyclin D1, D2, D3 and A protein levels in cardiac myocytes. Moreover, Ang II phosphorylated pRb on serine 780, which is known to occur in mitotic cells during cell cycle progression. Cultured cardiac myocytes treated with Ang II and infected with either control or recombinant adenovirus indicated that expression of p21 and p16 inhibited Ang II-induced cardiac myocyte hypertrophy, [3H]leucine incorporation into total cellular proteins, and skeletal alpha-actin (SK-A) and atrial natriuretic peptide (ANP) mRNA accumulation. Control virus had no effects on these parameters. These results suggest that G1 cyclins play an important role in cardiac myocyte hypertrophy stimulated by Ang II.  相似文献   
1000.
The purpose of this study was to provide further insight into the mechanism of bilirubin diglucuronide excretion through the hepatocyte canalicular membrane by investigating the uptake of (3H)bilirubin diglucuronide by purified canalicular membrane vesicles of rat liver. The uptake was analyzed by a rapid filtration technique. The difference between vesicle-associated (3H)bilirubin diglucuronide at 37 degrees C and at 0 degree C during the initial 1 min was regarded as uptake. Twenty second uptake was saturated by increasing the (3H)bilirubin diglucuronide concentration at a vesicle-inside-directed 100 mmol/L KCl gradient (Km = 75 mumol/L, Vmax = 320 pmol/mg protein.20 sec at 37 degrees C). No sodium dependency was observed. When canalicular membrane vesicles were preincubated with nonlabeled bilirubin diglucuronide, the uptake increased 1.3-fold (transstimulation). Vesicle-inside-positive potential induced by valinomycin and potassium caused a 1.4-fold increase in the uptake. When Cl- was replaced by equivalent ion concentrations of SO4(2-), HCO3-, NO3- and SCN-, the uptake was 78%, 244%, 68% and 50%, respectively, and specific stimulation by HCO3- was observed (Km = 75 mumol/L, Vmax = 700 pmol/mg protein.20 sec at a vesicle-inside-directed 100 mmol/L KHCO3 gradient at 37 degrees C). The uptake was inhibited in a dose-dependent manner by the addition of 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid. The uptake was ATP independent. From these results, it was concluded that bilirubin diglucuronide transport through the canalicular membrane is carrier mediated, electrogenic and stimulated by HCO3-.  相似文献   
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