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991.
The sodium intake modifies the renin-aldosterone and blood pressure changes associated with moderately low energy diets 总被引:1,自引:0,他引:1
B Fagerberg O K Andersson G Lindstedt J Waldenstr?m M Aurell 《Acta medica Scandinavica》1985,218(2):157-164
Thirty middle-aged, moderately obese men with untreated mild hypertension were allocated to two groups of 15 men each. Both groups were placed on energy-reduced diets (5.1 MJ/day) for 9-11 weeks which resulted in similar losses of body mass (8.5 kg). In group I the low energy diet was supplemented with sodium chloride leading to no change in urinary sodium excretion. During dieting there were significant reductions of plasma renin activity (PRA) and urinary excretion of noradrenaline and aldosterone. Heart rate but not mean arterial pressure (MAP) decreased significantly. Then followed a period of sodium restriction which resulted in a significant decrease in MAP and an increase in aldosterone excretion. In group II there was a reduction of sodium intake by about 80 mmol as judged from determinations of urinary sodium excretion. In this group the energy restriction was not accompanied by any changes in PRA or urinary excretion of aldosterone, whereas urinary noradrenaline excretion, heart rate and MAP decreased significantly. Urinary adrenaline excretion remained unchanged. It is concluded that the hypotensive response to moderate energy and sodium reduction cannot be explained by changes in the renin-aldosterone. system. 相似文献
992.
Effects of some peptides on isolated human penile erectile tissue and cavernous artery 总被引:3,自引:0,他引:3
Contractant and relaxant effects of four peptides known to occur in nerves innervating human penile vessels and erectile tissue, namely substance P (SP), vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY) and somatostatin, were studied in isolated preparations from the corpus cavernosum (CC), corpus spongiosum (CS) and cavernous artery (Acc). In addition, the actions of another peptide, arginine vasopressin (AVP), were investigated. In erectile tissue proper, SP induced concentration-dependent contractions. No effect of this peptide was observed in Acc segments. CC and CS preparations contracted by noradrenaline (NA) were relaxed by 30-40%; the effect in NA-contracted Acc preparations was inconsistent. AVP had a potent contractant effect in preparations from all the tissues studied, the effect being most conspicuous in CS strips. VIP was without contractant actions in any of the preparations. NA-contracted preparations were relaxed by VIP, and electrically induced contractions inhibited. The inhibitory effect was particularly marked in electrically stimulated CC and CS preparations. NPY had no effects; somatostatin contracted Acc segments, and in high concentrations CC and CS strips. It is concluded that among the peptides studied only VIP has effects compatible with a role as a neurotransmitter in penile erection. 相似文献
993.
Seasholtz TM Wessel J Rao F Rana BK Khandrika S Kennedy BP Lillie EO Ziegler MG Smith DW Schork NJ Brown JH O'Connor DT 《Hypertension》2006,47(5):937-947
The Rho/Rho kinase (ROCK) pathway is implicated in experimental hypertension. We, therefore, explored the role of ROCK2 genetic variation in human blood pressure (BP) regulation, exploiting the advantages of a human twin sample to probe heritability. The focus of this work is the common nonsynonymous variant at ROCK2: Thr431Asn. Cardiovascular and autonomic traits displayed substantial heritability (from approximately 33% to 71%; P<0.05). The Asn/Asn genotype (compared with Asn/Thr or Thr/Thr) was associated with greater resting systolic (P<0.001), diastolic (P<0.0001), and mean BP (P<0.0001); allelic variation at ROCK2 accounted for up to approximately 5% of BP variation (P<0.0001). Systemic vascular resistance was higher in Asn/Asn individuals (P=0.049), whereas cardiac output, large artery compliance, and vasoactive hormone secretion were not different. Coupling of the renin-angiotensin system to systemic resistance and BP was diminished in Asn/Asn homozygotes, suggesting genetic pleiotropy of Thr431Asn, confirmed by bivariate genetic analyses. The Asn/Asn genotype also predicted higher BP after environmental (cold) stress. The rise in heart rate after cold was less pronounced in Asn/Asn individuals, consistent with intact baroreceptor function, and baroreceptor slope was not influenced by genotype. Common genetic variation (Thr431Asn) at ROCK2 predicts increased BP, systemic vascular resistance (although not large artery compliance), and resistance in response to the endogenous renin-angiotensin system, indicating a resistance vessel-based effect on elevated BP. The results suggest that common variation in ROCK2 exerts systemic resistance-mediated changes in BP, documenting a novel mechanism for human circulatory control, and suggesting new possibilities for diagnostic profiling and treatment of subjects at risk of developing hypertension. 相似文献
994.
Canback B Andersson SG Kurland CG 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(9):6097-6102
Genes encoding the glycolytic enzymes of the facultative endocellular parasite Bartonella henselae have been analyzed phylogenetically within a very large cohort of homologues from bacteria and eukaryotes. We focus on this relative of Rickettsia prowazekii along with homologues from other alpha-proteobacteria to determine whether there have been systematic transfers of glycolytic genes from the presumed alpha-proteobacterial ancestor of the mitochondrion to the nucleus of the early eukaryote. The alpha-proteobacterial homologues representing the eight glycolytic enzymes studied here tend to cluster in well-supported nodes. Nevertheless, not one of these alpha-proteobacterial enzymes is related as a sister clade to the corresponding eukaryotic homologues. Nor is there a close phylogenetic relationship between glycolytic genes from Eucarya and any other bacterial phylum. In contrast, several of the reconstructions suggest that there may have been systematic transfer of sequences encoding glycolytic enzymes from cyanobacteria to some green plants. Otherwise, surprisingly little exchange between the bacterial and eukaryotic domains is observed. The descent of eukaryotic genes encoding enzymes of intermediary metabolism is reevaluated. 相似文献
995.
Vojvodich PF Hansen JB Andersson U Sävendahl L Hagelberg S 《The Journal of rheumatology》2007,34(12):2481-2485
OBJECTIVE: Anti-tumor necrosis factor (TNF) therapy is known to decrease disease activity of juvenile idiopathic arthritis (JIA), but its effect on longitudinal growth in relation to puberty is not clear. We studied longitudinal growth in response to etanercept treatment in prepubertal and pubertal patients with JIA. METHODS: Out of 52 children treated with etanercept, we studied 20 prepubertal and 11 early/midpubertal patients adherent to treatment for at least 1 year. We collected data on growth and glucocorticoid medication and calculated each patient's height standard deviation score (SDS) in relation to the mid-parental height, the change of this value (DeltahSDS) from 1 to 0 and 0 to 1 year of treatment, and the change between the DeltahSDS values to assess growth improvement. RESULTS: In the prepubertal group, the relative height SDS (mean +/- standard error of the mean) was 1.8 +/- 0.2, 2.1 +/- 0.3, and 1.9 +/- 0.3, and in the pubertal group 1.1 +/- 0.4, 1.3 +/- 0.3, and 1.1 +/- 0.3 at 1, 0, and +1 year of treatment, respectively. The DeltahSDS before etanercept was 0.3 +/- 0.1 in prepubertal and 0.2 +/- 0.2 in pubertal patients. Over the first year with etanercept, DeltahSDS was +0.2 +/- 0.1 in prepubertal (p = 0.001 vs before etanercept; paired Student t-test) and +0.2 +/- 0.1 in pubertal patients (p = 0.071). Nevertheless, most prepubertal (17/20) and pubertal (8/11) patients had improved growth (DeltahSDS) in response to etanercept treatment when analyzed individually. The need for intraarticular glucocorticoid injections was negatively correlated to the improved growth (p = 0.001). CONCLUSION: TNF inhibition with etanercept improved growth in a majority of patients with JIA. Our data demonstrate that growth improvement with etanercept was independent of the pubertal growth spurt. 相似文献
996.
A rapid and efficient immunization protocol for production of monoclonal antibodies reactive with autoantigens 总被引:8,自引:0,他引:8
A simple, time-saving and efficient immunization method suitable for the production of mouse monoclonal antibody secreting hybridomas is described. Draining lymph nodes isolated 9 days after a primary immunization were used as the source of antibody producing cells. No systemic spread of antibody producing cells or specific antibodies could be detected. The present protocol was employed to generate a panel of collagen type II reactive monoclonal antibodies. Most of the monoclonals so generated were found to be of the IgG class. 相似文献
997.
998.
Prevalence of type 1 Gaucher disease in the United States 总被引:1,自引:0,他引:1
Weinreb NJ Andersson HC Banikazemi M Barranger J Beutler E Charrow J Grabowski GA Hollak CE Kaplan P Mankin H Mistry PK Rosenbloom BE Vom Dahl S Zimran A 《Archives of internal medicine》2008,168(3):326-7; author reply 327-8
999.
OBJECTIVE: To investigate what factors are associated with physicians' decisions on whether or not to sickness certify the patient at a consultation. DESIGN: Questionnaire survey sent to physicians in general practice and their patients. SETTING: General practitioners in Orebro county, central Sweden. SUBJECTS: Sixty-five physicians with up to 10 patients each. MAIN OUTCOME MEASURE: Whether a sickness certificate was issued. RESULTS: Physicians with long experience in family medicine and those working part time issued more sickness certificates when all encounters with patients were considered. When only musculoskeletal problems were studied physicians with long experience or who were trained in social insurance medicine as undergraduates issued more sickness certificates. When only appointments for infections were studied, part-time physicians issued more sickness certificates. No impact of the physicians' sex on sickness certifying was found. CONCLUSIONS: Length of professional experience and physicians' working time appear to influence practices in sickness certifying. 相似文献
1000.
Li J Zhao J Hamer-Maansson JE Andersson T Fulmer R Illueca M Lundborg P 《Clinical therapeutics》2006,28(3):419-427
OBJECTIVE: The aim of this study was to assess the pharmacokinetic (PK) properties and tolerability of esomeprazole 20 and 40 mg after single and repeated oral doses in adolescents with symptoms of gastroesophageal reflux disease (GERD). RESULTS: The study included 15 boys and 13 girls (mean age, 14.3 years). Geometric mean AUC(0-infinity) values (overall drug exposure) were 1.58 and 5.57 micromol . h/L (0.027 and 0.083 pmol x h x L(-1)/kg) after single-dose administration of esomeprazole 20 and 40 mg, respectively, on day 1. Corresponding values with repeated doses (day 8) were 3.65 and 13.86 micromol x h/L (0.064 and 0.207 micromol x h x L(-1)/kg). Geometric mean Cmax values were 0.67 and 2.78 micromol/L (0.012 and 0.041 micromol/L x kg(-1)) with single-dose administration of esomeprazole 20 and 40 mg, respectively, and 1.45 and 5.13 micromol/L (0.026 and 0.075 micromol/L x kg(-1)), respectively, with repeated doses (day 8). These mean AUC(0-infinity) and CmaX values were >2-fold with the 40 mg dose compared with the 20-mg dose with single- and repeated-dose administration. The most common adverse event was headache (2 [7.1%] patients). CONCLUSIONS: The results of this study suggest that the PK parameters of esomeprazole were both dose- and time-dependent in these adolescents with GERD. Both doses of esomeprazole were well tolerated in this study population. 相似文献