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Prevalence of 22q11.2 deletions in 311 Dutch patients with schizophrenia   总被引:1,自引:0,他引:1  
The objectives of this study were 1) to examine whether the prevalence of 22q11.2 deletion syndrome (22q11DS) in schizophrenia patients with the Deficit syndrome is higher than the reported approximately 2% for the population of schizophrenia patients as a whole, and 2) to estimate the overall prevalence of 22q11DS among schizophrenia patients by combining all available studies. Our sample, enriched for patients with the Deficit syndrome, had 88% power to detect an estimated prevalence of 5% of 22q11.2 deletions. No 22q11.2 deletions were detected in 311 schizophrenia patients, 146 of whom met criteria for the Deficit syndrome. Our literature research revealed that in eight studies sixteen deletions were identified in 2133 patients with schizophrenia. This corresponds to a prevalence of 0.75% (95%CI: 0.5%-1.2%). In conclusion: The prevalence of 22q11.2DS in schizophrenia patients with the Deficit syndrome is not higher than in the population of schizophrenia patients as a whole. The prevalence of 22q11.2DS in schizophrenia patients is lower than the frequently reported prevalence of 2% or more.  相似文献   
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Isolated systolic hypertension is common in the elderly, but decreasing systolic blood pressure (SBP) without lowering diastolic blood pressure (DBP) remains a therapeutic challenge. Although stress management training, in particular eliciting the relaxation response, reduces essential hypertension its efficacy in treating isolated systolic hypertension has not been evaluated. We conducted a double-blind, randomized trial comparing 8 weeks of stress management, specifically relaxation response training (61 patients), versus lifestyle modification (control, 61 patients). Inclusion criteria were >or=55 years, SBP 140-159 mm Hg, DBP <90 mm Hg, and at least two antihypertensive medications. The primary outcome measure was change in SBP after 8 weeks. Patients who achieved SBP <140 mm Hg and >or=5 mm Hg reduction in SBP were eligible for 8 additional weeks of training with supervised medication elimination. SBP decreased 9.4 (standard deviation [SD] 11.4) and 8.8 (SD 13.0) mm Hg in relaxation response and control groups, respectively (both ps <0.0001) without group difference (p=0.75). DBP decreased 1.5 (SD 6.2) and 2.4 (SD 6.9) mm Hg (p=0.05 and 0.01, respectively) without group difference (p=0.48). Forty-four (44) in the relaxation response group and 36 in the control group were eligible for supervised antihypertensive medication elimination. After controlling for differences in characteristics at the start of medication elimination, patients in the relaxation response group were more likely to successfully eliminate an antihypertensive medication (odds ratio 4.3, 95% confidence interval 1.2-15.9, p=0.03). Although both groups had similar reductions in SBP, significantly more participants in the relaxation response group eliminated an antihypertensive medication while maintaining adequate blood pressure control.  相似文献   
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Background

Transitions often occur suddenly and can be traumatic to both patients with advanced disease and their families. The purpose of this study was to explore the transition experience of older rural persons with advanced cancer and their families from the perspective of palliative home care patients, bereaved family caregivers, and health care professionals. The specific aims were to: (1) describe the experience of significant transitions experienced by older rural persons who were receiving palliative home care and their families and (2) develop a substantive theory of transitions in this population.

Methods

Using a grounded theory approach, 27 open-ended individual audio-taped interviews were conducted with six older rural persons with advanced cancer and 10 bereaved family caregivers. Four focus group interviews were conducted with 12 palliative care health care professionals. All interviews were transcribed verbatim, coded, and analyzed using Charmaz's constructivist grounded theory approach.

Results

Within a rural context of isolation, lack of information and limited accessibility to services, and values of individuality and community connectedness, older rural palliative patients and their families experienced multiple complex transitions in environment, roles/relationships, activities of daily living, and physical and mental health. Transitions disrupted the lives of palliative patients and their caregivers, resulting in distress and uncertainty. Rural palliative patients and their families adapted to transitions through the processes of "Navigating Unknown Waters". This tentative theory includes processes of coming to terms with their situation, connecting, and redefining normal. Timely communication, provision of information and support networks facilitated the processes.

Conclusion

The emerging theory provides a foundation for future research. Significant transitions identified in this study may serve as a focus for improving delivery of palliative and end of life care in rural areas. Improved understanding of the transitions experienced by advanced cancer palliative care patients and their families, as well as the psychological processes involved in adapting to the transitions, will help health care providers address the unique needs of this vulnerable population.  相似文献   
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Genomic disorders contribute significantly to genetic disease and, as detection methods improve, greater numbers are being defined. Paralogous low copy repeats (LCRs) mediate many of the chromosomal rearrangements that underlie these disorders, predisposing chromosomes to recombination errors. Deletions of proximal 22q11.2 comprise the most frequently occurring microdeletion syndrome, DiGeorge/Velocardiofacial syndrome (DGS/VCFS), in which most breakpoints have been localized to a 3 Mb region containing four large LCRs. Immediately distal to this region, there are another four related but smaller LCRs that have not been characterized extensively. We used paralog-specific primers and long-range PCR to clone, sequence, and examine the distal deletion breakpoints from two patients with de novo deletions mapping to these distal LCRs. Our results present definitive evidence of the direct involvement of LCRs in 22q11 deletions and map both breakpoints to the BCRL module, common to most 22q11 LCRs, suggesting a potential region for LCR-mediated rearrangement both in the distal LCRs and in the DGS interval. These are the first reported cases of distal 22q11 deletions in which breakpoints have been characterized at the nucleotide level within LCRs, confirming that distal 22q11 LCRs can and do mediate rearrangements leading to genomic disorders.  相似文献   
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