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191.
The study provides a view of ideological meaning-making processes of 10 Israelis who lost a child examining the parents’ perspectives and written public documents. The texts and interviews were analyzed using Gadamer's hermeneutic philosophy. Findings indicate that bereaved parents construct conflicting ideologically oriented viewpoints: doubting and affirming the Zionist ideology; ascribing sense and senselessness to the loss; and joining the ethos but keeping personal meanings. Our conclusion is consistent with theorists who reject the notion that the human narrative should be coherently unified. We point to potential links between relational dialectics and meaning-making theory and outline implications for practice.  相似文献   
192.
Celiac disease is a common, familial autoimmune disease caused by exposure to gliadin in wheat, and related prolamins in barley and rye. The prevalence of the disease is approximately 1:133. Celiac disease can cause significant morbidity. The only treatment is a gluten-free diet. A genome-wide search of 405 microsatellite markers was performed on samples from 18 Bedouin families with a minimum of two cases of celiac disease. Non-parametric and parametric (including both dominant and recessive models of inheritance) linkage analyses were performed. The most significant genome-wide linkage evidence was at chromosome 3p26 with an HLod of 3.21, under the dominant model. The only other HLod or NPL greater than 2 was at 4q35, with an HLod of 2.15 under a dominant model. The region at 3p26, previously reported in two linkage analyses, harbors interleukin receptor genes, plausible candidates for celiac disease.  相似文献   
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Neutropenia, which may develop as a consequence of chemotherapy, increases the risk of bacterial infection. Similarly, increased risk of bacterial infection appears in disorders of phagocytic functions, such as the genetic disorder chronic granulomatous disease. To elucidate the organizing principles behind these distinct immunodeficiency conditions, we investigated the interaction between in vitro bacteria and human neutrophils by experiments and mathematical modeling. The model and the experiments showed that the in vitro bacterial dynamics exhibit bistability for a certain range of neutrophil concentration and function. Thus, there is a critical bacterial concentration above which infection develops, and below which neutrophils defeat the bacteria. Whereas with normal neutrophil concentration and function, an infection may develop when the initial bacterial concentration is very high, under neutropenic conditions or when there is neutrophil dysfunction, the critical bacterial concentration can be lower, within the clinically relevant range. We conclude that critical bacterial concentration has clinically relevant implications. The individual maximum bearable bacterial concentration depended on neutrophil concentration, phagocytic activity, and patient barrier integrity; thus, the resulting maximal bearable bacterial concentration may vary by orders of magnitude between patients. Understanding the interplay between neutrophils and bacteria may enhance the development of new therapeutic approaches to bacterial infections.  相似文献   
196.

Objective

We hypothesized that insulin resistance, measured by the homeostasis model assessment of insulin resistance (HOMA), is independently associated with prevalent and incident extra-coronary calcification (ECC).

Methods

We studied calcium scores of the aortic valve calcification (AVC), mitral valve calcification (MVC), thoracic aorta calcification (TAC) and aortic valve root calcification (AVR) in 6104 MESA participants not on diabetes medication who had baseline cardiac CT scans; 5312 had follow-up scans (mean 2.4 years). Relative-risk regression modeled prevalent and incident ECC adjusted for baseline demographics (model 1), and additionally for CVD risk factors (model 2).

Results

In model 1, prevalence and incidence risk-ratios for the highest versus lowest quartile of HOMA were 20–30% higher in all ECC locations (p-value for trend ≤0.05 for all but incident-AVC). In model 2, all associations were attenuated, primarily by adjustment for metabolic syndrome components.

Conclusions

HOMA has a positive and graded association with ECC, but not independently of cardiovascular risk factors—particularly metabolic syndrome components.  相似文献   
197.
Imatinib at a dose of 400 mg daily is considered frontline treatment in chronic phase chronic myeloid leukemia (CP-CML). We conducted a systematic review and meta-analysis of randomized controlled trials comparing frontline treatment with imatinib 400 mg daily versus higher doses (≥600 mg daily) in patients with CP-CML. The search yielded four trials, randomizing 1,673 patients. At 12 months, high dose compared with standard dose imatinib improved complete cytogenetic response (CCyR) (RR 1.17, 95% CI 1.08-1.26, four trials, I(2) = 33%) as well as major molecular response (MMolR) (RR 1.26, 95% CI 1.12-1.42, four trials, I(2) = 0%). There was no difference in all-cause mortality or disease progression at the end of follow up. Adverse events requiring discontinuation were more common in the high-dose arm (RR 1.98, 95% CI 1.20-3.26, three trials, I(2) = 0%), as were Grade III/IV neutropenia and thrombocytopenia: RR 1.56, 95% CI 1.15-2.12 and RR 1.86, 95% CI 1.28-2.70, respectively. There is currently insufficient evidence to support the routine use of higher doses of imatinib as frontline treatment for CP-CML. Extended follow up is needed to evaluate if the superior CCyR and MMolR with higher doses of imatinib will translate to long-term clinical benefit.  相似文献   
198.
Recent studies have demonstrated greater risks of cardiovascular events and mortality among persons who have lower 25-hydroxyvitamin D (25-OHD) and higher parathyroid hormone (PTH) levels. We sought to evaluate the association between markers of mineral metabolism and sudden cardiac death (SCD) among the 2312 participants from the Cardiovascular Health Study who were free of clinical cardiovascular disease at baseline. We estimated associations of baseline 25-OHD and PTH concentrations individually and in combination with SCD using Cox proportional hazards models after adjustment for demographics, cardiovascular risk factors, and kidney function. During a median follow-up of 14 years, there were 73 adjudicated SCD events. The annual incidence of SCD was greater among subjects who had lower 25-OHD concentrations, 2 events per 1000 for 25-OHD ≥20 ng/mL and 4 events per 1000 for 25-OHD <20 ng/mL. Similarly, SCD incidence was greater among subjects who had higher PTH concentrations, 2 events per 1000 for PTH <65 pg/mL and 4 events per 1000 for PTH ≥65 pg/mL. Multivariate adjustment attenuated associations of 25-OHD and PTH with SCD. Finally, 267 participants (11.7% of the cohort) had high PTH and low 25-OHD concentrations. This combination was associated with a >2-fold risk of SCD after adjustment (hazard ratio: 2.19 [95% CI: 1.17-4.10]; P=0.017) compared with participants with normal levels of PTH and 25-OHD. The combination of lower 25-OHD and higher PTH concentrations appears to be associated independently with SCD risk among older adults without cardiovascular disease.  相似文献   
199.
This study reports the effects of peripubertal GnRH receptor inactivation on development of psychophysiological motoric reactivity (PMR; sometimes also called emotional reactivity), plasma cortisol concentrations and the relationship between plasma cortisol and PMR in male and female sheep. The study formed part of a larger trial and utilised 46 same sex twins. One twin remained untreated (control) while the other received a subcutaneous GnRH agonist (GnRHa Goserelin-Acetate) implant every 4th week, beginning at 8 and 28 weeks of age, in males and females, respectively (different, due to sex specific age of puberty). PMR, a measure of an animals' response to social isolation, was measured over a two minute period at 8, 28 and 48 weeks of age, using a three axis accelerometer. During the test period vocalisation rate was recorded. Cortisol was assayed in blood samples collected on a single day when animals were 40 weeks of age. PMR and vocalisation rate were significantly higher in females than males at all ages tested. At 28 weeks of age (20 weeks treatment) PMR was increased in treated males to the level seen in control females, by 48 weeks of age treated males' PMR was significantly less than controls. In females, 20 weeks of GnRHa treatment (28-48 weeks of age) was not associated with differences in PMR. Cortisol concentrations were significantly higher in females than males but were not affected by treatment. Plasma cortisol concentrations were positively correlated with PMR; this relationship being driven by the treated animals in both sexes. The results demonstrate that PMR is sexually dimorphic and cortisol dependent in sheep from at least 8 weeks of age. Importantly, they also demonstrate that long-term treatment of males with a GnRH agonist results in changes in age-dependent development of PMR.  相似文献   
200.
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