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81.
We examined the effects of high salt intake on blood pressure and vascular 22Na uptake in Dahl salt-sensitive (DS) rats. At 6 weeks of age, one group of 6 DS rats was placed on a low (0.4%) salt diet and the second group of 6 DS rats was placed on a high (8.0%) salt diet for a period of 4 weeks. Blood pressure recordings were made weekly. At 10 weeks of age, the animals were sacrificed and aortic 22Na uptake was measured. Total and amiloride sensitive (Na(+)-H+ antiport) components of 22Na uptake were measured from which was calculated the amiloride insensitive component. Na+, K(+)-pumps were inhibited for these vascular 22Na uptake experiments with ouabain to prevent Na+ efflux. DS rats on the high salt diet demonstrated significantly (P less than 0.01) higher blood pressure when compared to DS rats on a low salt diet. Similarly, DS rats on a high salt diet demonstrated significantly (P less than 0.05) higher total, amiloride sensitive and amiloride insensitive vascular 22Na uptake as compared to DS rats on low salt diet. The parallel increase in vascular 22Na uptake and blood pressure suggests a possible, key role of Na+ influx in the mechanism of salt induced hypertension of DS rats. 相似文献
82.
Khadija EL. Mouaden D.S. Chauhan M.A. Quraishi Lahcen Bazzi 《Sustainable Chemistry and Pharmacy》2020
A facile single-step synthesis was performed to cross-link chitosan with thiocarbohydrazide to yield thiocarbohydrazide-chitosan (TC-Cht) which was for the first time evaluated as an inhibitor for corrosion of stainless steel in 3.5% NaCl solution. A comprehensive electrochemical analysis employing electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), and cyclic voltammetry (CV) was undertaken and showed that the TC-Cht acts by adsorption on the steel surface and exhibits mixed type behavior with predominantly cathodic nature. The adsorption of TC-Cht molecules on the surface of stainless steel followed the Langmuir isotherm. The TC-Cht showed a high inhibition efficiency of >94% at 500 mg L?1 concentration. Surface investigation using SEM and EDX supported the inhibitor adsorption on the steel surface. 相似文献
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Ariane Sampson Daniel S. F. Figueiredo Huw G. Jeremiah Dauro D. Oliveira Laize R. P. Freitas Michele Chahoud Rodrigo V. Soares Martyn T. Cobourne 《The Angle orthodontist》2021,91(3):363
ObjectivesTo investigate the relationship between the use of social networking sites (SNSs) on patient perceptions, acceptance, and expectations of treatment using temporary anchorage devices (TADs) and to compare differences between patients from the United Kingdom and Brazil.Materials and MethodsCross-sectional questionnaires were administered to 39 participants at orthodontic practices in the United Kingdom and Brazil about patients'' use of SNSs, exposure to TADs on SNSs, and thoughts on extractions, jaw surgery, or TADs as treatment options.ResultsUK patients prefer for clinicians to have SNS profiles (P = .022). Most UK and Brazilian patients want to see their clinician''s work online (76.7%) and use SNSs to get information about treatment options (76.6%). There was a statistically significant difference in Brazilian patients'' acceptance of TADs as a treatment option compared with UK patients, particularly if it meant avoiding extractions (P = .002), avoiding jaw surgery (P = .004), or reducing treatment time (P = .010). Knowledge of TADs was greater in Brazilian patients (P < .001).ConclusionsPatients use SNSs to obtain information about treatments and prefer clinicians to have social media accounts. Patients exposed to TADs on SNSs are more likely to accept them as an orthodontic treatment option. UK patients have less knowledge of TADs and are therefore less sure to consider TADs as an option. Brazilian patients are more confident in considering the use of TADs. Clinicians should consider increasing their social media presence to accommodate patients'' expectations and acceptance of TADs. 相似文献
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Uchechukwu K Sampson Marc A Pfeffer John J V McMurray Yuliya Lokhnygina Harvey D White Scott D Solomon 《European heart journal》2007,28(6):685-691
AIMS: We sought to determine risk models for predicting early and late stroke in a large cohort of high-risk post-myocardial infarction (MI) patients. METHODS AND RESULTS: We prospectively analysed data from 14 703 patients in the VALIANT trial with acute MI complicated by heart failure, left ventricular (LV) systolic dysfunction, or both. Patients were randomized 0.5-10 days after acute MI to valsartan, captopril, or their combination. We evaluated risk factors for early (<45 days) and late (>45 days) stroke by using multivariable Cox proportional hazards regression analyses with stepwise variable selection techniques applied to 92 pre-specified potential predictor variables. After randomization, 463 (3.2%) patients had fatal (n = 124) or non-fatal (n = 339) strokes, with 134 strokes occurring in the first 45 days. The strokes were classified as ischaemic (348), haemorrhagic (40), or of indeterminate cause (75). Estimated glomerular filtration rate and heart rate when in sinus rhythm were the most powerful predictors of early stroke (<45 days after MI), whereas diastolic blood pressure (DBP) >90 mmHg, prior stroke, and atrial fibrillation (AF) were the most powerful predictors of stroke overall. Ejection fraction and sex were not predictive of stroke in this cohort. CONCLUSION: Among high-risk patients presenting with MI but without initial neurological symptoms, the risk of stroke 6 weeks thereafter is 0.94% (95% CI 0.78-1.09). Of the most powerful baseline predictors of stroke, DBP and AF are amenable to therapeutic interventions and thus merit special attention in these patients. 相似文献
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Bodo B. Beck Jennifer B. Phillips Malte P. Bartram Jeremy Wegner Michaela Thoenes Andrea Pannes Josephina Sampson Raoul Heller Heike Göbel Friederike Koerber Antje Neugebauer Andrea Hedergott Gudrun Nürnberg Peter Nürnberg Holger Thiele Janine Altmüller Mohammad R. Toliat Simon Staubach Kym M. Boycott Enza Maria Valente Andreas R. Janecke Tobias Eisenberger Carsten Bergmann Lars Tebbe Yang Wang Yundong Wu Andrew M. Fry Monte Westerfield Uwe Wolfrum Hanno J. Bolz 《Human mutation》2014,35(10):1153-1162
We describe a consanguineous Iraqi family with Leber congenital amaurosis (LCA), Joubert syndrome (JBTS), and polycystic kidney disease (PKD). Targeted next‐generation sequencing for excluding mutations in known LCA and JBTS genes, homozygosity mapping, and whole‐exome sequencing identified a homozygous missense variant, c.317G>C (p.Arg106Pro), in POC1B, a gene essential for ciliogenesis, basal body, and centrosome integrity. In silico modeling suggested a requirement of p.Arg106 for the formation of the third WD40 repeat and a protein interaction interface. In human and mouse retina, POC1B localized to the basal body and centriole adjacent to the connecting cilium of photoreceptors and in synapses of the outer plexiform layer. Knockdown of Poc1b in zebrafish caused cystic kidneys and retinal degeneration with shortened and reduced photoreceptor connecting cilia, compatible with the human syndromic ciliopathy. A recent study describes homozygosity for p.Arg106ProPOC1B in a family with nonsyndromic cone‐rod dystrophy. The phenotype associated with homozygous p.Arg106ProPOC1B may thus be highly variable, analogous to homozygous p.Leu710Ser in WDR19 causing either isolated retinitis pigmentosa or Jeune syndrome. Our study indicates that POC1B is required for retinal integrity, and we propose POC1B mutations as a probable cause for JBTS with severe PKD. 相似文献
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