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41.
OBJECTIVE: To determine the relative risk of severe intraventricular hemorrhage (IVH) between two very early indomethacin treatment strategies. STUDY DESIGN: Retrospective chart review of infants <29 weeks gestation and <1350 g who received either indomethacin prophylaxis or very early echocardiography with indomethacin treatment only if the ductus arteriosus was patent. RESULTS: A total of one hundred and two infants received prophylactic indomethacin (pINDO). Echochardiography was performed on 158 infants, of whom 117 received indomethacin. Infants receiving pINDO had lower gestational age, but similar birth weight, gender, race, antenatal steroid exposure, delivery mode, Apgar scores, and need for resuscitation as infants evaluated by echocardiography. Grades III to IV IVH was observed less frequently in infants who received pINDO (OR 0.27, 95% CI 0.10 to 0.77, p=0.014). Frequency of side effects and recurrent patent ductus arteriosus did not differ between treatment groups. CONCLUSION: pINDO reduces severe IVH when compared to an early echocardiography strategy.  相似文献   
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PURPOSE: Macrophage inhibitory cytokine-1 (MIC-1) is a divergent member of the tumor growth factor beta (TGF-beta) superfamily. Several observations suggest that it plays a role in colorectal carcinoma (CRC). In particular, MIC-1 is markedly up-regulated in colorectal cancers as well as in premalignant adenomas. This study examines the relationship of serum MIC-1 levels and genotypes to clinical and pathologic features of colonic neoplasia. Experimental Design: We confirmed the presence of MIC-1 in CRC tissue and the cell line CaCo-2. The normal range for serum MIC-1 levels was defined in 260 healthy blood donors, and the differences between normal subjects and 193 patients having adenomatous polyps or CRC were then determined. In a separate cohort of 224 patients, we evaluated the relationship of MIC-1 serum level and genotype to standard tumor parameters and outcome measures. RESULTS: MIC-1 was expressed in CRC tissue and the cancer cell line CaCo-2. There was a progressive increase in serum MIC-1 levels between normal individuals [mean (M) = 495 pg/ml, SD = 210), those with adenomatous polyps (M = 681 pg/ml, SD = 410), and those with CRC (M = 783 pg/ml, SD = 491)]. Serum MIC-1 level was correlated with the extent of disease so that the levels were higher in patients with higher Tumor-Node-Metastasis stage. There were significant differences in time to relapse and overall survival between subjects with different MIC-1 levels and genotypes. CONCLUSIONS: This study identifies a strong association between MIC-1 serum levels and neoplastic progression within the large bowel. We suggest that the measurement of serum MIC-1 levels and determination of MIC-1 genotype may have clinical use in the management of patients with CRC.  相似文献   
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Objective : To assess the skin irritant potential of a range of laboratory grown cyanobacterial species using skin-patch testing on human volunteers.
Methods : Cell suspensions and extracts of cyanobacterial cultures of Microcystis aeruginosa (non-toxic strain), Anabaena circinalis and Nodularia spumigena were applied to 64 volunteers in one trial, and Microcystis aeruginosa (toxic strain), Apanocapsa incerta and Cylindrospermopsis raciborskii were applied to 50 volunteers in a second trial. Six cell concentrations of each organism in the range from less than 5,000 to greater than 200,000 cells/ml were applied in random order using adhesive skin patches (Finn Chambers). In addition, the applications included two treatments of each cyanobacterial species, involving whole and lysed cells, and positive (sodium lauryl sulphate) and negative (culture media) controls. Patches were removed after 24 hours and assessment of erythema was made by a dermatologist blinded to the species, cell type and concentration.
Results : On average, between 20% and 24% of individuals with 95% confidence interval ±8% reacted across the concentration range tested for these cyanobacterial species. The reaction rates were lower (11% to 15%) among the subset of subjects not reacting to negative controls. The reaction was mostly mild, and in all cases was resolved without treatment. This was the case for both whole and lysed cells with little difference in reaction rates between these two treatments. There was also no dose-response across the concentration range for any of the cyanobacterial species tested.
Conclusion : A small proportion of healthy people (around 20%) may develop a skin reaction to cyanobacteria in the course of normal water recreation, but the reaction is mild and resolved without treatment.  相似文献   
46.
Rejection sensitivity is a cognitive-affective processing disposition that has been linked to interpersonal difficulties. In this regard, the neuropeptide hormone, oxytocin, is thought to underlie social cognitions and behaviors that promote social affiliation. A single nucleotide polymorphism (SNP) on the oxytocin receptor gene (OXTR), in which guanine (G) is substituted for adenine (A), has been associated with less support-seeking behaviors. In the current study, among 376 undergraduate students, it was shown that the relationship between rejection sensitivity and depressive symptoms was mediated by multiple group memberships. Furthermore, the relation between rejection sensitivity and group memberships was only evident among individuals possessing the A allele on the OXTR gene. These findings further support the psychosocial deficits characteristic of individuals possessing the OXTR polymorphism, which in turn is linked to poor mood.  相似文献   
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Patients born with congenital right ventricular outflow tract lesions are faced with invasive procedures to establish hemodynamic and physiological stability. Commonly, multiple subsequent surgical procedures are required due to deterioration of a previous repair. These procedures carry additive risks of mortality and morbidity. Less aggressive procedures with accompanying lower risk is ideal. Success in percutaneously placing a transcatheter valve has previously been reported; however, continued safety and efficacy of any technique needs continual assessment. We developed a model for preclinical evaluation of a percutaneous placement of a pulmonic transcatheter valve in adult sheep, including preoperative, surgical, and postoperative techniques for long-term evaluation. Adult sheep were assessed and determined to be acceptable for study enrollment. Perioperative antibiotics and analgesics were given prior to a left thoracotomy. A Medtronic, Hancock 1 valve conduit was inserted for reconstruction of the right ventricular outflow tract. The Hancock 1 valve conduit alone represented the control group and the test animals comprised the addition of a Melody? transcatheter pulmonary valve (TPV), within the Hancock 1 valve conduit. Fifteen adult sheep survived the surgical implant procedure with no perioperative mortality. There were four early postoperative deaths, three due to infection and one due to heart failure, secondary to intraoperative heart block. The remaining 11 animals remained healthy, gained weight, and survived to termination at 5 months. An initial definite-sized valve conduit was implanted, followed by inserting a single size TPV, which allowed a more accurate physiological assessment of any chosen valve. Our developed adult sheep model for percutaneous TPV implantation for right ventricular outflow tract lesions was successful for long-term assessment by utilizing our preoperative, surgical, and postoperative techniques.  相似文献   
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Current literature suggests that a large proportion of chest X-rays (CXRs) performed in emergency department (ED) patients with chest pain and suspected acute coronary syndrome (ACS) are unnecessary. The Canadian ACS Guidelines aim to guide clinicians in the appropriate use of CXR within this patient population. This study determined the prevalence of clinically significant CXR abnormalities and assessed the utility of the guidelines in a population of ED patients with chest pain and suspected ACS. Included in the study were participants over the age of 18 who presented to an Australian metropolitan ED, over a 1-year period, with a primary complaint of chest pain and who had a CXR and troponin level ordered in the ED (N?=?760). We retrospectively compared their radiographic findings with their recommendations for CXR according to the ACS Guidelines. We found that 12 % of the participants had a clinically significant chest X-ray. The guidelines had a sensitivity of 80 % (95 % CI 0.70–0.87) and specificity of 50 % (95 % CI 0.47–0.54). The positive predictive value was 18 % (95 % CI 0.15–0.22) with a 95 % negative predictive value (95 % CI 0.92–0.97). Had the ACS guidelines been applied to our patient population, the number of CXR performed would have been reduced by 47 %. This study suggests that the ACS Guidelines has the potential to reduce the numbers of unnecessary CXR performed in ED patients. However, this would come at the expense of missing a minority of significant CXR abnormalities.  相似文献   
50.
Journal of Muscle Research and Cell Motility - This study reports that in rat skeletal muscle the proteins specifically responsible for mitochondrial dynamics, mitofusin-2 (MFN2) and mitochondrial...  相似文献   
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