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排序方式: 共有427条查询结果,搜索用时 937 毫秒
41.
Takenoshita S; Hagiwara K; Gemma A; Nagashima M; Ryberg D; Lindstedt BA; Bennett WP; Haugen A; Harris CC 《Carcinogenesis》1997,18(7):1427-1429
The transforming growth factor-beta type II receptor (RII) is commonly
mutated in colon and gastric cancers with microsatellite instability (MI).
We utilized our series of lung cancers with MI and rare alleles of the
H-ras1 gene to determine the association between MI and RII mutations and
searched the entire RII coding region in 33 lung cancers with MI by
polymerase chain reaction-single-strand conformation polymorphism analysis.
We found no mutations, and these data support other recent evidence that
RII mutations rarely occur except in colon and gastric tumors with MI.
相似文献
42.
43.
Occurrence and treatment of Mycoplasma genitalium in patients visiting STD clinics in Sweden 总被引:6,自引:0,他引:6
Johannisson G Enström Y Löwhagen GB Nagy V Ryberg K Seeberg S Welinder-Olsson C 《International journal of STD & AIDS》2000,11(5):324-326
Two hundred and thirty-three men and 85 women visiting STD clinics in western Sweden between April 1997 and March 1998 were examined for Mycoplasma genitalium and Chlamydia trachomatis. The bacteria were identified by the polymerase chain reaction (PCR) technique. Three women (3.5%) and 18 men (7%) were positive for M. genitalium. Seventeen (14%) of the 115 men with urethritis were infected but only one of the men was without urethritis. After treatment with tetracyclines for 10 days, one woman and 8 of the 13 men still harboured M. genitalium. M. genitalium-infected men did not have more life-time partners than other men visiting STD clinics. More men positive for M. genitalium gave a history of previous urethritis but the difference was not significant. 相似文献
44.
B Ryberg Y Tielemans J Axelson E Carlsson R H?kanson H Mattson F Sundler G Willems 《Gastroenterology》1990,99(4):935-942
The enterochromaffinlike cells in the rat stomach are rich in histamine and are thought to be under the influence of gastrin. The effect of sustained endogenous and exogenous hypergastrinemia on the activity and proliferation rate of the enterochromaffinlike cells was studied by determining the histidine decarboxylase activity and histamine concentration and by combining histamine immunocytochemistry and autoradiography after in vivo labeling with [3H]thymidine. The proliferation rate of the stem cells in the oxyntic mucosal progenitor zone was also studied. Exogenous hypergastrinemia was induced by infusion of rat gastrin-17 (60 nmol.kg-1.day-1). Endogenous hypergastrinemia was induced by inhibition of gastric acid secretion with omeprazole (80 mumol.kg-1.day-1) or ranitidine (1200 mumol.kg-1.day-1). The effect of omeprazole was also studied in antrectomized rats. In intact rats, all treatments resulted in elevated plasma gastrin levels and were accompanied by an increase in the histidine decarboxylase activity and the histamine content of the oxyntic mucosa. This resulted in an increase in the enterochromaffinlike cell proliferation rate, leading to enterochromaffinlike cell hyperplasia. The number of labeled stem cells was increased, but this effect was not as pronounced as in the enterochromaffinlike cells. In antrectomized rats, the inhibition of acid secretion by omeprazole did not result in elevated plasma gastrin or in an increase in the activity or number of enterochromaffinlike cells, indicating that omeprazole per se had no effect on these cells. These data support the view that gastrin stimulates the proliferation rate of both enterochromaffinlike cells and stem cells. Gastrin also stimulates the activity of the enterochromaffinlike cells. 相似文献
45.
Davies M Lavalle-González F Storms F Gomis R;AT.LANTUS Study Group 《Diabetes, obesity & metabolism》2008,10(5):387-399
Objective: For many patients with type 2 diabetes, oral antidiabetic agents (OADs) do not provide optimal glycaemic control, necessitating insulin therapy. Fear of hypoglycaemia is a major barrier to initiating insulin therapy. The AT.LANTUS study investigated optimal methods to initiate and maintain insulin glargine (LANTUS®, glargine, Sanofi-aventis, Paris, France) therapy using two treatment algorithms. This subgroup analysis investigated the initiation of once-daily glargine therapy in patients suboptimally controlled on multiple OADs. Research Design and Methods: This study was a 24-week, multinational (59 countries), multicenter (611), randomized study. Algorithm 1 was a clinic-driven titration and algorithm 2 was a patient-driven titration. Titration was based on target fasting blood glucose ≤100 mg/dl (≤5.5 mmol/l). Algorithms were compared for incidence of severe hypoglycaemia [requiring assistance and blood glucose <50 mg/dl (<2.8 mmol/l)] and baseline to end-point change in haemoglobin A1c (HbA1c). Results: Of the 4961 patients enrolled in the study, 865 were included in this subgroup analysis: 340 received glargine plus 1 OAD and 525 received glargine plus >1 OAD. Incidence of severe hypoglycaemia was <1%. HbA1c decreased significantly between baseline and end-point for patients receiving glargine plus 1 OAD (−1.4%, p < 0.001; algorithm 1 −1.3% vs. algorithm 2 −1.5%; p = 0.03) and glargine plus >1 OAD (−1.7%, p < 0.001; algorithm 1 −1.5% vs. algorithm 2 −1.8%; p = 0.001). Conclusions: This study shows that initiation of once-daily glargine with OADs results in significant reduction of HbA1c with a low risk of hypoglycaemia. The greater reduction in HbA1c was seen in patients randomized to the patient-driven algorithm (algorithm 2) on 1 or >1 OAD. 相似文献
46.
47.
Eosinophil functions can be modulated by several cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin- 3 (IL-3), and IL-5. We have investigated the modulatory role of these cytokines on the interaction of human eosinophils with opsonized particles (serum-treated zymosan [STZ]). Addition of STZ to eosinophils isolated from the peripheral blood of normal human donors resulted in an interaction of the STZ particles with only 15% to 25% of the cells. Treatment of the eosinophils with GM-CSF, IL-3, or IL-5 strongly enhanced both the rate of particle binding and the percentage of eosinophils binding STZ. The effect of the cytokines is most likely mediated by a change in affinity of the complement receptor type 3 (CR3) on the eosinophils for the complement fragment iC3b on the STZ particles. This is indicated by the observation that (1) the effect of the cytokines on STZ binding was prevented by a monoclonal antibody against the iC3b-binding site on CR3 and (2) the enhanced binding was already apparent before upregulation of CR3 on the cell surface was observed. In a previous study, similar results were obtained with platelet-activating factor (PAF)-primed eosinophils. Because we found that the cytokines strongly enhanced the STZ-induced PAF synthesis, we investigated the role of both released PAF and cell-associated PAF in the priming phenomenon by the cytokines. Cytokine priming appeared to be largely independent of the synthesis of PAF. 相似文献
48.
Correlation between inhibition of gastric acid secretion, plasma gastrin, and oxyntic mucosal histidine decarboxylase activity in the rat 总被引:1,自引:0,他引:1
B Ryberg H Mattsson H Larsson E Carlsson 《Scandinavian journal of gastroenterology》1989,24(3):287-292
Female rats were treated for 1 week with ranitidine (125-1700 mumol/kg.day, given subcutaneously by means of osmotic minipumps), the proton pump inhibitor omeprazole (10-400 mumol/kg.day orally), or vehicle. Acid secretion, plasma gastrin levels, and oxyntic mucosal histidine decarboxylase (HDC) activity were determined. Both compounds dose-dependently inhibited maximally stimulated gastric acid secretion and caused a parallel increase in plasma gastrin levels. There was very good correlation between plasma gastrin levels and HDC activity for both compounds, although higher oxyntic mucosal HDC activity was found during ranitidine treatment. The higher HDC activity in the ranitidine-treated rats indicated the presence of a histamine H2-receptor on the ECL cells. It is concluded that, regardless of what kind of antisecretory agent is used, a dose-dependent inhibition of gastric acid secretion results in a parallel increase in plasma levels of gastrin, and as a consequence the HDC activity in the rat oxyntic mucosa is increased. 相似文献
49.
Deprivation of dietary nucleotides decreases protein synthesis in the liver and small intestine in rats 总被引:1,自引:0,他引:1
AT Lopez-Navarro MA Ortega J Peragon JD Bueno A Gil A Sanchez-Pozo 《Gastroenterology》1996,110(6):1760-1769
BACKGROUND & AIMS: Dietary nucleotides are reported to influence the growth and functioning of the liver and small intestine. The aim of this study was to examine the mechanism by which nucleotides exert their effects in these tissues by assessing protein synthesis activity and related parameters in the presence or absence of dietary nucleotides. METHODS: Rats were fed a purified diet with or without nucleotides for 10 days. Fractional protein synthesis rate, RNA and DNA concentrations, polysome size distribution, and number of ribosomes were assessed. RESULTS: Fractional protein synthesis rates of the liver and small intestine were lower in the nucleotide-deprived group than in the control group. In the liver, RNA concentration was also lower in the nucleotide-deprived group, but values in the small intestine were similar in the two groups. In the liver, deprivation of nucleotides resulted in a reduction in the number of ribosomes and in polysome breakdown. Protein and DNA concentrations did not vary in the liver; however, the concentration of DNA was lower in the small intestine of the nucleotide-deprived group than in the control group. CONCLUSIONS: Dietary nucleotides can modulate protein synthesis in the liver and small intestine as a result of tissue-specific nucleic acid changes. (Gastroenterology 1996 Jun;110(6):1760-9) 相似文献
50.