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91.
Objective. Oxygen-dependent changes in vascular diameters may be detrimental when the endothelium is dysfunctional. Design. Endothelial responsiveness was evaluated by brachial ultrasound and flow-mediated/nitroglycerin-mediated dilation (FMD/NMD). FMD/NMD was investigated in males with increased risk of cardiovascular disease (mean age 44±2 years, n =10) and matched controls without risk factors (44±2 years, n =10). FMD/NMD was assessed during normoxia (21% O2, 79% N2), while inhaling hypoxic gas (12.5% O2, FMDHyp/NMD), and 100% O2 supplementation (FMDO2/NMD). In a second study we addressed the effect of lipid lowering. Twenty persons with cardiovascular risk (mean age 50±2 years) were treated with atorvastatin (80 mg/day) and FMD/NMD was measured during normoxia, hypoxia and oxygen supplementation before, after 1 day and 3 months. Results. Oxygen supplementation evoked vasoconstriction, while FMDHyp/NMD was reduced compared to FMD/NMD. Atorvastatin significantly lowered total cholesterol, LDL cholesterol, and ADMA after 1 day of treatment, while triglycerides, ApoB and hsCRP were lowered after 3 months. Atorvastatin did not change FMD/NMD irrespective of oxygen tension. Conclusion. Irrespective of risk factors or atorvastatin, hypoxia reduced endothelial vasodilation while oxygen supplementation evoked vasoconstriction.  相似文献   
92.
Objective - The underlying mechanisms of the differences in sex distribution of patients with atrioventricular (AV) nodal re-entrant tachycardia and Wolff-Parkinson-White syndrome are poorly understood. The objective of this study was to determine potential gender differences in the electrophysiological properties of the normal AV conduction system that may be attributable to differences in sex distribution. Design - The AV conduction properties were studied in 96 patients (52 men and 44 women) who underwent electrophysiological testing, 32 patients with atrial tachycardia, 39 with idiopathic ventricular tachycardia and 25 with unexplained palpitations or syncope. Results - The AH (83 &#45 15 ms) and His-ventricular intervals in men (42 &#45 6 ms) were significantly longer than in women (78 &#45 14, 38 &#45 6 ms, p < 0.05, respectively), as was the PR interval (160 &#45 17 vs 152 &#45 13 ms, p = 0.02). The effective refractory period of AV node in men (349 &#45 75 ms) was longer than in women (297 &#45 45 ms, p = 0.03). However, no significant difference was observed between men and women with respect to the incidence of AV nodal dual pathway and the maximum AH interval achieved during premature stimulation or incremental pacing. The AV block cycle length was significantly longer in men (371 &#45 76 ms) than in women (330 &#45 52 ms, p = 0.02). A longer ventriculoatrial block cycle length was also found in men than in women although not at a significant level (436 &#45 107 vs 384 &#45 90 ms, p = 0.08). In addition, men (23%) were twice as likely to have ventriculoatrial dissociation during ventricular pacing as women were (11%, p = 0.2). Conclusion - The data show that gender-related differences in AV conduction properties may be responsible for the differences in sex distribution observed in patients with AV nodal re-entrant tachycardia and those with ventricular pre-excitation.  相似文献   
93.
Objective. The aim of the study was to evaluate the impact of an additional subcutaneous suture line on the incidence of postoperative (p.o.) infection at the vena saphena magna harvesting site (VSMHS) after coronary artery bypass grafting (CABG). Methods. Two hundred and forty three patients undergoing CABG were included. Patients in Group A (n?=?119) all operated by one physical assistant (PA) were prospectively randomised into Group A1 (n?=?59) receiving intracutaneous closure suture alone whereas 60 patients (Group A2) received an additional subcutaneous suture line. Group B (n?=?120), operated by surgical residents, served as control population. All patients were due to follow-up at six weeks p.o. Results. Subcutaneous suture did not impact the p.o. infection rate (A2 vs. A1; 4/60 vs. 2/59, n.s.). A significant lower p.o. infection rate was observed in Group A vs. Group B (6/119 (5%) vs. 15/120 (13%) p?<?0.05). Conclusion. Subcutaneous suture did not impact the p.o. infection rate at VSMHS. The infection rate observed in patients operated by an experienced PA was significantly lower than in patients operated by various surgical residents.  相似文献   
94.
Objective: An examination of the genetic background and phenotypic presentation of familial hypertrophic cardiomyopathy (FHC) with respect to specific mutations in the MYH7  相似文献   
95.
BackgroundEvidence of associations between neurocognitive function and cannabis use in schizophrenia is inconclusive. However, direct measures of cannabis intake and premorbid function are rarely explored in this context. We investigated the relation between cannabis use, determined by its presence in urine, and neurocognitive functioning in schizophrenia controlling for the potential bias of premorbid functioning.MethodsNaturalistic study of 364 patients with schizophrenia spectrum disorder from catchment areas in Oslo, Norway. Hierarchical multiple regression analyses were used to assess the relationship between cannabis in urine and measures of neurocognitive functioning, with adjustment for confounders, including premorbid functioning.ResultsCannabis was detected in the urine of 21 patients, who had significant dysfunction in several neurocognitive domains independent of a current diagnosis of cannabis abuse. However, level of premorbid functioning explained the associations for all measures.ConclusionDifferences in premorbid functioning may explain apparent differences in neurocognitive function between schizophrenia spectrum patients using cannabis or not. The findings suggest that illness-related traits present early in life can affect both later cannabis use and neurocognition, probably by complex mechanisms.  相似文献   
96.
Objectives Previous studies have suggested that urine albumin excretion (UAE) mirrors generalized vascular damage; however, it is unclear to which degree UAE mirrors small artery impairment. Design We enrolled 67 patients with uncomplicated essential hypertension (EH) during stable antihypertensive therapy. F-Rmin, ACR on three non-consecutive morning urine samples, pulse wave velocity (PWV), and 24-h ambulatory blood pressure (ABPM) were measured. Results ACR was low (0.39 and 0.30–0.60), but abnormal small artery structure defined as F-Rmin?>?mean?+?2 standard deviations of normotensive value (1.99?+?1?mmHg min/(ml/100?ml)) was present in 45% (n?=?30). The mean F-Rmin was 2.89?±?0.09?mmHg min/(ml/100?ml). ACR correlated significantly to PWV (r2?=?0.11; p?<?0.05) and pulse pressure (r2?=?0.15; p?<?0.001), but not F-Rmin and (r2?=?0.05, p?=?0.07). Conclusions Abnormal microvascular structure was present even in EH patients with low UAE. ACR correlated to arterial stiffness and not to small artery structure; therefore, UEA did not reflect microvascular damage in this population. ACR and F-Rmin thus reflect two distinct types of subclinical organ damage in hypertension.  相似文献   
97.
Ficolin-2 is a serum opsonin, which has been shown to be a pattern recognition molecule in the lectin complement activation pathway. Because innate immune mechanisms are involved in maintaining tissue homeostasis we hypothesized that Ficolin-2 also participate in the clearance of dying host cells. We found that Ficolin-2 binds to late apoptotic cells, as well as to apoptotic bodies and necrotic cells, but not to early apoptotic cells. We demonstrated that Ficolin-2 binds DNA in a calcium dependent manner and that DNA inhibits the binding to late apoptotic and necrotic cells, suggesting that DNA on permeable dying cells is a plausible ligand. Reconstituting serum deficient of Ficolin-2, C1q and mannose-binding lectin with Ficolin-2 augmented deposition of complement C4 on necrotic cells. Opsonization leads to an enhanced attachment/uptake of necrotic cells by macrophages. In conclusion dying host cells expose ligands with the capacity of binding Ficolin-2, which in turn leads to increased attachment and engulfment. Binding of Ficolin-2 to DNA points at nucleic acid exposed by permeable late apoptotic and necrotic cells as one of the ligands for Ficolin-2. Ficolin-2 may therefore be a scavenger molecule participating in the removal of host cells and maintenance of tissue homeostasis.  相似文献   
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Porcine reproductive and respiratory syndrome virus (PRRSV) is prevalent in Danish swine herds. In July 2019, PRRSV‐1 was detected in a PRRSV‐negative boar station and subsequently spread to more than 38 herds that had received semen from the boar station. Full genome sequencing revealed a sequence of 15.098 nucleotides. Phylogenetic analyses showed that the strain was a recombination between the Amervac strain (Unistrain PRRS vaccine; Hipra) and the 96V198 strain (Suvaxyn PRRS; Zoetis AH). The major parent was the 96V198 strain that spanned ORFs 1–2 and part of ORF 3 and the minor parent was the Amervac strain, which constituted the remaining part of the genome. The virus seems to be highly transmissible and has caused severe disease in infected herds despite a high level of genetic identity to the attenuated parent strains. The source of infection was presumable a neighbouring farm situated 5.8 km from the boar station.  相似文献   
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