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991.
Essential hypertension is associated with reduced endothelium-dependent vasodilation, mainly due to reduced nitric oxide and an increase in vasoconstrictors such as endothelin-1 and angiotensin II. Endothelial dysfunction has been shown to be associated with an increased incidence of cardiovascular events and to have prognostic significance. The reduction of blood pressure per se is insufficient for improving endothelial function, and antihypertensive drugs show contrasting effects in terms of improvement or restoration of endothelial function. 相似文献
992.
993.
Internalization of sst2, sst3, and sst5 receptors: effects of somatostatin agonists and antagonists. 总被引:4,自引:0,他引:4
Renzo Cescato Stefan Schulz Beatrice Waser Véronique Eltschinger Jean E Rivier Hans-Jürgen Wester Michael Culler Mihaela Ginj Qisheng Liu Agnes Schonbrunn Jean Claude Reubi 《Journal of nuclear medicine》2006,47(3):502-511
The uptake of radiolabeled somatostatin analogs by tumor cells through receptor-mediated internalization is a critical process for the in vivo targeting of tumoral somatostatin receptors. In the present study, the somatostatin receptor internalization induced by a variety of somatostatin analogs was measured with new immunocytochemical methods that allow characterization of trafficking of the somatostatin receptor subtype 2 (sst2), somatostatin receptor subtype 3 (sst3), and somatostatin receptor subtype 5 (sst5) in vitro at the protein level. METHODS: Human embryonic kidney 293 (HEK293) cells expressing the sst2, sst3, or the sst5 were used in a morphologic immunocytochemical internalization assay using specific sst2, sst3 and sst5 antibodies to qualitatively and quantitatively determine the capability of somatostatin agonists or antagonists to induce somatostatin receptor internalization. In addition, the internalization properties of a selection of these agonists have been compared and quantified in sst2-expressing CHO-K1 cells using an ELISA. RESULTS: Agonists with a high sst2-binding affinity were able to induce sst2 internalization in the HEK293 and CHO-K1 cell lines. New sst2 agonists, such as Y-DOTA-TATE, Y-DOTA-NOC, Lu-DOTA-BOC-ATE (where DOTA is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid; TATE is [Tyr3, Thr8]-octreotide; NOC is [1-NaI3]-octreotide; and BOC-ATE is [BzThi3, Thr8]-octreotide), iodinated sugar-containing octreotide analogs, or BIM-23244 were considerably more potent in internalizing sst2 than was DTPA-octreotide (where DTPA is diethylenetriaminepentaacetic acid). Similarly, compounds with high sst3 affinity such as KE108 were able to induce sst3 internalization. In sst2- or sst3-expressing cell lines, agonist-induced receptor internalization was efficiently abolished by sst2- or sst3-selective antagonists, respectively. Antagonists alone had no effect on sst2 or sst3 internalization. We also showed that somatostatin-28 and somatostatin-14 can induce sst5 internalization. Unexpectedly, however, potent sst5 agonists such as KE108, BIM-23244, and L-817,818 were not able to induce sst5 internalization under the same conditions. CONCLUSION: Using sensitive and reproducible immunocytochemical methods, the ability of various somatostatin analogs to induce sst2, sst3, and sst5 internalization has been qualitatively and quantitatively determined. Whereas all agonists triggered sst2 and sst3 internalization, sst5 internalization was induced by natural somatostatin peptides but not by synthetic high-affinity sst5 agonists. Such assays will be of considerable help for the future characterization of ligands foreseen for nuclear medicine applications. 相似文献
994.
Catarina Eira Jordi Miquel José Vingada Jordi Torres 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(2):119-122
Gongylonema neoplasticum was identified in the oesophagus of 14 wild rabbits (Oryctolagus cuniculus) from Portugal. This is the first record of Gongylonema neoplasticum in a naturally infected lagomorph species in Europe. This paper presents the most relevant measurements of adult worms and
some of their surface features seen by scanning electron microscopy. Epidemiological aspects of G. neoplasticum such as geographical distribution, host spectrum and biological features are discussed. 相似文献
995.
Intravenous immunoglobulin (Ig IV) has been used for many years in the treatment of primary antibody deficiencies. We performed a retrospective study of the clinical features and outcome of agammaglobulinemia children who received prolonged Ig IV infusions. PATIENTS AND METHODS: Ten children, 9 male et 1 female, with agammaglobulinemia diagnosis were studied for the clinical manifestations before and during the Ig IV replacement therapy. Serum Ig levels were quantified by nephelometry. Circulating B ant T cells were counted by immunofluorescence labeling by monoclonal antibodies. T-cell functions were assessed by using mitogen and antigen -induced T-cell proliferation assays in vitro. Patients clinical status was evaluated respectively, before initiation and at every moment (when patients had an infection) of the replacement therapy. RESULTS: Ig IV therapy was performed for 866 cumulated months, median 108 months. The median Ig IV doses administered to the 10 patients was 500 mg/kg/month. Residual serum IgG mean level was 3,9 g/L. All patients had 99 bacterial infections/year before Ig IV, mainly respiratory tract infections (48,5%), and 4 patients had bronchiectasis before Ig replacement therapy. The number of infection/year fall to 25 during IgIV replacement, and the infection/patient/year rate decreases significantly. One patient developed an Echovirus 27 meningoencephalitis during this treatment. CONCLUSION: Ig IV therapy with residual IgG mean level of 3,9 g/l reduced significantly the rate of bacterial infections. The use of specific antibiotherapy and respiratory kinesitherapy led to a lower rate of respiratory tract infections, and the stabilisation of the bronchiectasis. However this intravenous replacement therapy does not protect against viral meningoencephalitis. 相似文献
996.
通过比较国产MAR AsAb试剂盒与进口IBT AsAb试剂盒 ,验证国产MAR AsAb试剂盒的真实性和可靠性。以进口IBT AsAb试剂盒为对照 ,对 42 0例不育症患者精液标本进行检测 ,比较抗精子抗体检出情况。发现 :国产MAR AsAb试剂盒与进口IBT AsAb试剂盒 ,阳性率分别为 8.8%和 8.3 % ,经配对 χ2 检验无显著差异 (P >0 .0 5 )。国产MAR AsAb试剂盒灵敏度为 94.6% ,特异度为 1 0 0 %。同一份精液标本重复检测 1 0次 ,变异系数CV =2 .5 9%。提示 :国产MAR AsAb试剂盒灵敏度高、特异性好、重复性高 ,符合临床诊断的要求。 相似文献
997.
This study aimed to identify risk factors for type 2 diabetes (T2D) in Korea, a rapidly changing country. Data of 5,132 adults aged 20-85 were used from the 2001 Korean Health and Nutrition Examination Survey. Multiple logistic regression was carried out to identify risk factors for T2D. Three models were specified: (i) socioeconomic and demographic factors (model 1: age, gender, education, poverty income ratio, employment), (ii) behavioral risk factors and covariates (model 2: obesity, physical activity, smoking, alcohol drinking, dietary quality, family history of T2D, co-morbidity) and (iii) socioeconomic, demographic, and behavioral factors (model 3). The prevalence of T2D was 7.4%. Less education (OR 1.41, 95% CI 1.08-1.84), age (OR 2.19, 95% CI 1.56-3.08 in 40-59 yrs, OR 4.05, 95% CI 2.76-5.95 in 60 yrs + comparing to 20-39 yrs) and abdominal obesity (OR 2.24, 95% CI 1.79-2.82) were risk factors for T2D even after controlling for other factors simultaneously. There was a significant association of T2D with ever smoking (OR 1.34, 95% CI 1.06-1.67). The relationship of age with T2D was modified by gender in model 1 and the relationship of smoking with T2D was modified by obesity in model 2. Less educated, older, obese or ever smokers were more likely to have T2D. Gender mediated the relationship of age, and obesity mediated the relationship of smoking, with T2D. Intervention programs for T2D in Korea should take the interactions among risk factors into account. 相似文献
998.
999.
1000.
Alfredo Avellaneda Fernández álvaro Pérez Martín Maravillas Izquierdo Martínez Mar Arruti Bustillo Francisco Javier Barbado Hernández Javier de la Cruz Labrado Rafael Díaz-Delgado Pe?as Eduardo Gutiérrez Rivas Cecilia Palacín Delgado José Ramón Ramón Giménez Javier Rivera Redondo 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2009,41(10):e1-e5