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131.
132.
Very high-pressure orogenic garnet peridotites   总被引:3,自引:0,他引:3  
Mantle-derived garnet peridotites are a minor component in many very high-pressure metamorphic terranes that formed during continental subduction and collision. Some of these mantle rocks contain trace amounts of zircon and micrometer-sized inclusions. The constituent minerals exhibit pre- and postsubduction microstructures, including polymorphic transformation and mineral exsolution. Experimental, mineralogical, petrochemical, and geochronological characterizations using novel techniques with high spatial, temporal, and energy resolutions are resulting in unexpected discoveries of new phases, providing better constraints on deep mantle processes.  相似文献   
133.
Qi X  Li L  Yang G  Liu J  Li K  Tang Y  Liou H  Boden G 《Clinical endocrinology》2007,66(4):593-597
BACKGROUND: Obestatin is a novel hormone that is encoded by the Ghrelin gene and produced in the gut. Ghrelin is profoundly orexogenic and adipogenic, increasing food intake and body weight. This new ghrelin-associated peptide behaves as a physiological opponent of ghrelin in rodent animals, but its pathophysiological role in humans remains unknown OBJECTIVE: In this study we investigate whether plasma obestatin level is different in patients with impaired glucose regulation (IGR) and type 2 diabetes mellitus (T2DM). PATIENTS AND MEASUREMENTS: Forty-seven patients with T2DMu, 30 subjects with IGR, and 38 sex- and age-matched normal controls participated in the study. Plasma obestatin levels were measured with a radioimmunoassay. The relationship between plasma obestatin levels and anthropometric and metabolic parameters was also analysed. RESULTS: Plasma obestatin levels were lower in patients with T2DM and IGR than in controls (37.5 +/- 9.2 ng/l and 39.2 +/- 9.7 ng/l vs. 43.8 +/- 8.0 ng/l, P = 0.002 and P = 0.039, respectively). Decreasing concentrations of obestatin were independently and significantly associated with IGR and T2DM. Multiple logistic regression analysis revealed obestatin to be independently associated with IGR and T2DM. In a multiple linear regression analysis, only waist-to-hip ratio and homeostasis model assessment of insulin resistance (HOMA-IR) were independently associated with plasma obestatin level. CONCLUSION: Our results suggest that obestatin may play a role in appetite regulation in patients with IGR and T2DM.  相似文献   
134.
Background:  The interleukin 17A ( IL17A ) gene, located on chromosome 6p and linked to asthma phenotype, is a highly potential candidate gene conferring asthma susceptibility. The purpose of this study was to investigate the genetic association between single nucleotide polymorphisms (SNPs) of IL17A and asthma in Taiwanese children.
Methods:  We selected and performed genotyping on nine SNPs that encompass the genomic region of IL17A in Taiwanese children with or without asthma. A total of 1939 subjects containing 1027 subjects in testing group and 931 subjects in validation group were recruited in this study.
Results:  After Bonferroni correction, SNP rs8193036 was found to have a weak association ( P  = 0.0074 × 9 = 0.066) in genotype frequency test. This association was confirmed by validation group. Logistic regression adjusted allergy comorbidity and gender showed a slightly weaker association.
Conclusions:  The results indicated an independent role of IL17A promoter polymorphism rs8193036 in the association with pediatric asthma in Taiwanese population.  相似文献   
135.
The pro-inflammatory cytokine interleukin-1 beta has been implicated in the pathogenesis of major depressive disorder and in cognitive function decline in the elderly. This study tests the hypothesis that a biallelic functional polymorphism in the promoter region of the interleukin-1 beta gene (IL1B −511C/T) affects vulnerability to geriatric depression and its manifestations, including age of onset, depression severity, and cognitive function. We genotyped the IL1B −511C/T polymorphism in 125 elderly inpatients diagnosed with major depression and 282 normal elderly controls. The depressed patients were evaluated at baseline after admission using the Hamilton Rating Scale for Depression (HAM-D) for depression severity and the Mini-Mental Status Examination (MMSE) for cognitive function; depression age of onset was evaluated by interview and medical records. We found no association between IL1B −511C/T genotypes and geriatric depression susceptibility (P = 0.213), depression severity (HAM-D scores; P = 0.766) or cognitive function (MMSE scores; P = 0.827); however, compared with depressed subjects carrying the −511C allele, depressed subjects who were −511T homozygotes showed a significantly later depression age of onset of 7 years (P = 0.021). Our findings suggest that the IL1B −511C/T polymorphism may be related to age at manifestation among individuals vulnerable to depression, but they do not affect the basic vulnerability to or severity of depression in elderly Chinese adults. Further study is warranted to confirm this finding and to assess its generalization to other ethnic groups.  相似文献   
136.
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An analysis of the concept of organizational commitment   总被引:1,自引:0,他引:1  
Liou SR 《Nursing forum》2008,43(3):116-125
TOPIC.   Building organizational commitment.
PURPOSE.   This paper aims to analyze the concept of organizational commitment, including its attributes, antecedents, outcomes, and measurements.
SOURCES OF INFORMATION.   CINAHL, MEDLINE, Psychology and Behavioral Sciences Collection, Sociological Collection, and PubMed.
CONCLUSION.   By understanding the concept of organizational commitment, administrators and nurses can become more aware of their levels of commitment, bridge gaps in communication, and eventually provide higher-quality care to clients.  相似文献   
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140.
Status epilepticus results in preferential neuronal cell loss in the hippocampus. We evaluated the hypothesis that the repertoire of intracellular events in the vulnerable hippocampal CA3 subfield after induction of experimental temporal lobe status epilepticus entails upregulation of nitric oxide synthase II (NOS II), followed by the release of mitochondrial cytochrome c that triggers the cytosolic caspase-3 cascade, leading to apoptotic cell death. In Sprague-Dawley rats, significant and temporally correlated upregulation of NOS II (3-24h), but not NOS I or II expression, enhanced cytosolic translocation of cytochrome c (days 1 and 3), augmented activated caspase-3 in cytosol (days 1, 3 and 7) and DNA fragmentation (days 1, 3 and 7) was detected bilaterally in the hippocampal CA3 subfield after elicitation of sustained seizure activity by microinjection of kainic acid into the unilateral CA3 subfield. Application bilaterally into the hippocampal CA3 subfield of a selective NOS II inhibitor, S-methylisothiourea, significantly blunted these apoptotic events; a selective NOS I inhibitor, N(omega)-propyl-l-arginine or a potent NOS III inhibitor, N(5)-(1-iminoethyl)-l-ornithine was ineffective. We conclude that upregulation of NOS II contributes to apoptotic cell death in the hippocampal CA3 subfield via a cytochrome c/caspase-3 signaling cascade following the induction of experimental temporal lobe status epilepticus.  相似文献   
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