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This study aims to gain insight in the motivational process of the Job Demands-Resources (JD-R) model by examining whether daily fluctuations in colleague support (i.e., a typical job resource) predict day-levels of job performance through self-efficacy and work engagement. Forty-four flight attendants filled in a questionnaire and a diary booklet before and after consecutive flights to three intercontinental destinations. Results of multilevel analyses revealed that colleague support had unique positive effects on self-efficacy and work engagement. Self-efficacy did not mediate the relationship between support and engagement, but work engagement mediated the relationship between self-efficacy and (in-role and extra-role) performance. In addition, colleague support had an indirect effect on in-role performance through work engagement. These findings shed light on the motivational process as outlined in the JD-R model, and suggest that colleague support is an important job resource for flight attendants helping them reach their work-related goals.  相似文献   
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OBJECTIVE

This study investigated the association between arterial stiffness and plasma adiponectin in patients with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Participants were normotensive patients with type 1 diabetes who were up to age 40 years. Subjects on statins with macrovascular disease or overt nephropathy were excluded. Large artery stiffness was assessed by measurement of carotid-femoral pulse wave velocity (PWV), whereas plasma adiponectin was measured by radioimmunoassay.

RESULTS

Data from 80 patients (age 27.1 ± 6.1 years, BMI 24.2 ± 3.1 kg/m2, HbA1c 7.5 ± 1.6%, 39 men, adiponectin 13.9 ± 6.7 μg/mL, and PWV 5.6 ± 0.9 m/s) were analyzed. Log adiponectin inversely correlated with age-adjusted PWV (r = −0.291, P = 0.009) and waist circumference (r = −0.427, P < 0.001). In a fully adjusted model, age, expiration/inspiration index, and log adiponectin were independently associated with PWV, explaining 39.6% of its variance.

CONCLUSIONS

Arterial stiffness is inversely related to adiponectin concentration in young patients with type 1 diabetes without major complications.Arterial stiffness, an independent predictor of total and cardiovascular mortality, can be assessed noninvasively by measurement of pulse wave velocity (PWV) (1), which is increased at early stages of type 1 diabetes (2,3). Plasma adiponectin, an adipocytokine with insulin-sensitizing, antiatherogenic, and anti-inflammatory properties (4), is high in patients with type 1 diabetes (5,6). Although adiponectin is inversely related to arterial stiffness in subjects with essential hypertension (7,8), no adiponectin-PWV relationship has been shown in children/adolescents with type 1 diabetes (9). This study investigated the association between adiponectin and PWV in young adults with type 1 diabetes.  相似文献   
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BACKGROUND: Familial hypercholesterolemia (FH) is a genetic disorder characterized by high low-density lipoprotein-cholesterol (LDL-C) concentrations, which frequently gives rise to premature coronary artery disease. The clinical expression of FH is highly variable, even in patients carrying the same LDL receptor (LDLR) gene mutation. This variability may be due to environmental and other genetic factors. METHODS: We investigated paraoxonase 2 (PON 2) Ser311Cys, lipoprotein lipase (LPL) Asn291Ser, plasminogen activator inhibitor-1 (PAI-1) T11053G, beta-fibrinogen (FGB) -455 G>A and nitric oxide synthase gene (NOS) -922 A>G polymorphisms in 84 patients with FH. The effect of polymorphisms as independent factors of high lipid values was evaluated. RESULTS: The PON 2 Cys311 allele was correlated with high total cholesterol and LDL-C and apolipoprotein B levels, while LPL Asn291, PAI-1 T11053, FGB -455 G and NOS -922 A alleles were correlated with high apolipoprotein B levels. CONCLUSIONS: These results suggest that apolipoprotein B levels in FH heterozygotes may be affected by several different genetic variants.  相似文献   
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Amifostine is a phosphorylated aminothiol that not only protects hematopoietic progenitor cells from chemotherapy and radiotherapy, but also stimulates normal hematopoiesis. The effect of amifostine on the in vitro growth of hematopoietic progenitors derived from B-cell chronic lymphocytic leukemia(B-CLL) was investigated. The colony-forming units (CFU)-granulocyte macrophage (CFU-GM), the burst-forming units-erythroid (BFU-E) and the CFU-granulocyte erythroid macrophage megakaryocytes (CFU-GEMM) increased 38, 20 and 100%, respectively, after the incubation with amifostine. There was no statistical difference in the in vitro progenitor growth of patients grouped according to their disease stage, bone marrow lymphocytic infiltration or therapy. Our data indicate that apart from cytoprotection the parallel use of amifostine and chemotherapy in patients with B-CLL could enhance bone marrow recovery.  相似文献   
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Purpose

To analyze the impact on patient outcome of ventilator-associated events (VAEs) as defined by the Centers for Disease Control and Prevention (CDC) in 2008, 2013, and the correlation with ventilator-associated pneumonia (VAP) or tracheobronchitis (VAT).

Methods

This was a prospective, observational, multicenter, international study conducted at 13 intensive care units (ICUs); thirty consecutive adults mechanically ventilated for ≥?48 h per site were eligible, with daily follow-up being recorded in a collaborative web database; VAEs were assessed using the 2013 CDC classification and its 2015 update.

Results

A total of 2856 ventilator days in 244 patients were analyzed, identifying 33 VAP and 51 VAT episodes; 30-day ICU mortality was significantly higher (42.8 vs. 19.6%, p?<?0.007) in patients with VAP than in those with VAT. According to the 2013 CDC definitions, 117 VAEs were identified: 113 (96%) were infection-related ventilator-associated complication-plus (IVAC-plus), while possible ventilator-associated pneumonia (PVAP) was found in 64 (56.6%) of them. VAE increased the number of ventilator days and prolonged ICU and hospital LOS (by 5, 11, and 12 days, respectively), with a trend towards increased 30-day mortality (43 vs 28%, p?=?0.06). Most episodes (26, 55%) classified as IVAC-plus without PVAP criteria were due to atelectasis. PVAP significantly increased (p?<?0.05) ventilator days as well as ICU and hospital LOS (by 10.5, 14, and 13 days, respectively). Only 24 (72.7%) of VAP and 15 (29.4%) of VAT episodes met IVAC-plus criteria.

Conclusions

Respiratory infections (mainly VAT) were the most common complication. VAE algorithms only identified events with surrogates of severe oxygenation deterioration. As a consequence, IVAC definitions missed one fourth of the episodes of VAP and three fourths of the episodes of VAT. Identifying VAT (often missed by IVAC-plus criteria) is important, as VAP and VAT have different impacts on mortality.
  相似文献   
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Blood pressure (BP) in patients with sickle cell disease (SCD) has been reported to be lower than in persons in the general population. Data on arterial stiffness, which is an important risk factor for the progression of BP, are inconclusive for this patient population. Forty‐five adult patients with SCD and 40 controls matched for sex, age, and body mass index were studied. Brachial systolic BP (SBP) and diastolic BP (DBP) were significantly lower in the patient group (SBP 115.1±13.8 mm Hg vs 121.9±11.3 mm Hg and DBP 68.5±8.0 mm Hg vs 80.6±9.1 mm Hg, P<.05, respectively). Augmentation index (AIx), however, was significantly higher in SCD patients compared with healthy controls (24.9±9.6 for patients vs 12.4±10.8 for controls, P<.001), while carotid femoral pulse wave velocity was comparable between the two groups. The study shows that mechanisms other than arterial elasticity are involved in the low BP phenotype of patients with SCD.  相似文献   
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