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41.
The purpose of this study is to measure soluble CD14 (sCD14) levels in sera from newborn with sepsis, to compare it with other markers, and to study its evolution in Gram-negative and Gram-positive sepsis. Forty normal newborns were included (26 were full term and 14 were preterm infants), 20 babies had a positive blood culture (11 Gram-positive and 9 Gram-negative) and 16 cases were suspected of having sepsis based on clinical and laboratory findings, but a negative blood culture. Interleukin-6 (IL-6), sCD14, and tumour necrosis factor-α (TNFα) were measured by enzyme immunoassay, and fibronectin (FN) and C-reactive protein (CRP) by radial immunodiffusion. Neonates with a positive blood culture had increased levels of sCD14(3.20 ± 1.26μgml-1, p < 0.001), CRP(69 ± 46 μgml-1, p < 0.001)and IL-6 (134 ± 150 pg ml-1, p < 0.001), and decreased values of FN (12.3 ± 6.6 mg ml-1, p < 0.001). TNFα levels were also high (160 ± 37 pg ml-1), but this increase was not statistically significant. Newborn infants suspected of having sepsis but a negative blood culture had similar but milder abnormalities. Soluble CD 14 levels correlated with CRP values; however, there was no correlation between sCD 14, TNFα and IL-6. Neonates with sepsis by Gram-positive bacteria had lower sCD14 levels than patients with Gram-negative sepsis (2.63 ± 1.2 versus 4.04 ± 1.0μgml-1, p < 0.05). In conclusion, the sCD14 level is increased in newborn infants with sepsis, and this is higher in infections by Gram-negative bacteria, suggesting a different contribution of monocyte and macrophage cells. In contrast, IL-6, TNFα, CRP and FN values are similar in infections by Gram-positive and Gram-negative bacteria.  相似文献   
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We examined the effect of dietary supplementation with L-arginine on breath condensate VEGF, exhaled nitric oxide (NO), plasma erythropoietin, symptoms of acute mountain sickness, and respiratory related sensations at 4,342 m through the course of 24 h in seven healthy male subjects. Serum L-arginine levels increased in treated subjects at time 0, 8, and 24 h compared with placebo, indicating the effectiveness of our treatment. L-arginine had no significant effect on overall Lake Louise scores compared with placebo. However, there was a significant increase in headache within the L-arginine treatment group at 12 h compared with time 0, a change not seen in the placebo condition between these two time points. There was a trend (p = 0.087) toward greater exhaled NO and significant increases in breath condensate VEGF with L-arginine treatment, but no L-arginine effect on serum EPO. These results suggest that L-arginine supplementation increases HIF-1 stabilization in the lung, possibly through a NO-dependent pathway. In total, our observations indicate that L-arginine supplementation is not beneficial in the prophylactic treatment of AMS.  相似文献   
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Infidelity is a common issue with which distressed couples and their therapists grapple. However, there are no data on the efficacy of commonly used therapies to treat couples in which there has been an affair. In the present exploratory study, the authors examined the therapy outcomes of a sample of infidelity couples (n=19) who had participated in a randomized clinical trial of marital therapy (N=134). Results show that infidelity couples began treatment more distressed than noninfidelity couples; however, evidence suggests that couples who had an affair and who revealed this affair prior to or during therapy showed greater improvement in satisfaction than noninfidelity couples. Implications for therapy with infidelity couples are discussed.  相似文献   
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BACKGROUND: The amount of dietary fat required for optimal bioavailability of carotenoids in plant matrices is not clearly defined. OBJECTIVE: The objective was to quantify the appearance of carotenoids in plasma chylomicrons after subjects ingested fresh vegetable salads with fat-free, reduced-fat, or full-fat salad dressings. DESIGN: The subjects (n = 7) each consumed 3 salads consisting of equivalent amounts of spinach, romaine lettuce, cherry tomatoes, and carrots with salad dressings containing 0, 6, or 28 g canola oil. The salads were consumed in random order separated by washout periods of > or =2 wk. Blood samples were collected hourly from 0 to 12 h. Chylomicrons were isolated by ultracentrifugation, and carotenoid absorption was analyzed by HPLC with coulometric array detection. RESULTS: After ingestion of the salads with fat-free salad dressing, the appearance of alpha-carotene, beta-carotene, and lycopene in chylomicrons was negligible. After ingestion of the salads with reduced-fat salad dressing, the appearance of the carotenoids in plasma chylomicrons increased relative to that after ingestion of the salads with fat-free salad dressing (P < 0.04). Similarly, the appearance of the carotenoids in plasma chylomicrons was higher after the ingestion of salads with full-fat than with reduced-fat salad dressing (P < 0.02). CONCLUSIONS: High-sensitivity HPLC with coulometric array detection enabled us to quantify the intestinal absorption of carotenoids ingested from a single vegetable salad. Essentially no absorption of carotenoids was observed when salads with fat-free salad dressing were consumed. A substantially greater absorption of carotenoids was observed when salads were consumed with full-fat than with reduced-fat salad dressing.  相似文献   
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Quantification of tumour response to radiotherapy   总被引:4,自引:0,他引:4  
In 1979, the World Health Organization (WHO) established criteria based on tumour volume change for classifying response to therapy as (i) progressive disease (PD), (ii) partial recovery (PR), and (iii) no change (NC). Typically, the tumour volume is reported from diameter measurements, using the calliper method. Alternatively, the Cavalieri method provides unbiased volume estimates of any structure without assumptions about its shape. In this study, we applied the Cavalieri method in combination with point counting to investigate the changes in tumour volume in four patients with high grade glioma, using 3D MRI. In particular, the volume of tumour within the enhancement boundary, the enhancing abnormality (EA), was estimated from T(1) weighted images, and the volume of the non-enhancing abnormality, (NEA) enhancing abnormality, was estimated from T(2) relaxation time and magnetic transfer ratio tissue characterization maps. We compared changes in tumour volume estimated by the Cavalieri method with those obtained using the calliper method. Absolute tumour volume differed significantly between the two methods. Analysis of relative change in tumour volume, based on the WHO criteria, provided a different classification using the calliper and Cavalieri methods. The benefit of the Cavalieri method over the calliper method in the estimation of tumour volume is justified by the following factors. First, Cavalieri volume estimates are mathematically unbiased. Second, the Cavalieri method is highly efficient under an appropriate sampling density (i.e. EA volume estimates can be obtained with a coefficient of error no higher than 5% in 2-3 min). Third, the source of variation of the volume estimates due to disagreements between observers, and within observer, is much greater in the positioning of the calliper diameters than in the identification of the tumour boundaries when applying the Cavalieri method. Additionally, the error prediction formula, available to estimate the coefficient of error of Cavalieri volume estimates from the data, allows us to establish more precise classification criteria against which to identify potentially clinical significant changes in tumour volume.  相似文献   
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