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1.
Haemoglobin (Hb) abnormalities in chronic obstructive pulmonary disease (COPD) are not well characterised. The present authors investigated the prevalence and association of abnormal Hb with clinical outcomes. Analysis of a prospective cohort of stable COPD outpatients (n = 683) in a USA Veterans Administration pulmonary clinic was undertaken. Patients were classified as anaemic (Hb <13 g.dL(-1)), polycythemic (Hb > or =17 g.dL(-1) and > or =15 g.dL(-1) for males and females, respectively) or normal. Demographic characteristics and physiological/functional outcomes were compared between groups. Regression models adjusting for confounders examined the independent association of anaemia with clinical outcomes. Anaemia was present in 116 (17%) patients and polycythemia in 40 (6%). While the only values that differed between polycythemic and nonpolycythemic patients were mean body mass index and Hb, anaemic patients showed a significantly higher modified Medical Research Council dyspnoea scale score (2.8 versus 2.6), lower 6-min walk distance (265 versus 325 m) and shorter median survival (49 versus 74 months) than nonanaemic patients. In regression models, anaemia independently predicted dyspnoea and reduced exercise capacity. Anaemia in chronic obstructive pulmonary disease was an independent risk factor for reduced functional capacity. Polycythemia prevalence was low and had no association with worsened outcomes. Further work is required to evaluate the effect of anaemia correction on outcomes in chronic obstructive pulmonary disease.  相似文献   
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PURPOSE: To examine relationships among childhood adversity, attachment style (one's core beliefs regarding the self and others), and the following risk behaviors and contexts among young men who have sex with men (YMSM): homelessness, daily substance use, participation in sex work, involvement in the criminal justice system, and being out of school or work. METHODS: Using a targeted sampling approach, we recruited 569 YMSM aged 17-28 years from natural venues in New York City including bars, clubs, parks, and bus stations. Youth completed a structured interview assessing lifetime and current risk and protective contexts and behavior. Data were analyzed using univariate and multivariate statistical methods, including hierarchical logistic regression. RESULTS: After controlling for demographic characteristics and childhood adversity, YMSM with a fearful attachment style were more likely to have been homeless (OR 2.93, 95% CI 1.65-5.18), to have participated in sex work (OR 2.35, 95% CI 1.44-3.85), to use substances daily (OR 2.79, 95% CI 1.29-6.03), to have been involved in the criminal justice system (OR 2.04, 95% CI 1.38-3.01), and to be out of school/work (OR 2.47, 95% CI 1.47-4.15). Three subgroups were particularly vulnerable: YMSM who identified as heterosexual, or bisexual, and/or transgender. CONCLUSIONS: A fearful attachment style contributes to some YMSM remaining outside of the protective systems of family, school, and work, and is associated with risky contexts where they are less likely to encounter prosocial peers and adults. Further, it is associated with risk behavior. Although gay-identified youth are generally found to have poor outcomes when compared with the general population of adolescents, in the present report, YMSM who identified as heterosexual were at particular risk. Attachment theory can guide interventions by informing how individuals experience relationships and manage developmental transitions.  相似文献   
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Multiple hormones controlling energy homeostasis regulate the expression of neuropeptide Y (NPY) and agouti-related peptide (AgRP) in the arcuate nucleus of the hypothalamus. Nevertheless, inactivation of the genes encoding NPY and/or AgRP has no impact on food intake in mice. Here we demonstrate that induced selective ablation of AgRP-expressing neurons in adult mice results in acute reduction of feeding, demonstrating direct evidence for a critical role of these neurons in the regulation of energy homeostasis.  相似文献   
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Primary tumor growth and metastasis depend on angiogenesis, which is determined by the balance between proangiogenic and antiangiogenic molecules. Interferon (IFN)-α and -β inhibit angiogenesis through downregulation of interleukin-8, matrix metalloproteinase-9, and basic fibroblast growth factor. To provide evidence for the causal role of IFN-α/β in the induction of neoplasms, their angiogenesis, and hence, progressive growth, we carried out experiments using 129S6 IFN-α/β receptor −/− mice back-crossed to BALB/c nude mice. Subcutaneous angiogenesis was determined following implantation of gelfoam sponges containing 0.4% agarose and several proangiogenic molecules. Tumorigenicity and production of lung metastasis were determined subsequent to subcutaneous and intravenous injections, respectively, of highly metastatic A375SM human melanoma cells. Carcinogenesis was induced by chronic exposure of mice to UVB radiation (5 kJ/m2, 3 times/week). Angiogenesis, tumorigenicity, and production of metastasis, as well as development of autochthonous skin tumors, were all accelerated in IFN-α/β receptor −/− mice as compared to control mice. Collectively, the data show that inability to respond to endogenous IFN-α/β (through a mutation in the IFN-α/β receptor) leads to increased susceptibility to carcinogenesis, enhanced angiogenesis, tumorigenicity, and metastasis. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Advances in Health Sciences Education - Spaced education is a learning strategy to improve knowledge acquisition and retention. To date, no robust evidence exists to support the utility of spaced...  相似文献   
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Identifying novel mechanisms, which are at the core of breast cancer biology, is of critical importance. Such mechanisms may explain response to treatment, reveal novel targets or drive detection assays.To uncover such novel mechanisms, we used survival analysis on gene expression datasets encompassing 1363 patients. By iterating over the compendia of genes, we screened for their significance as prognosis biomarkers and identified SUMO-specific protease 5 (SENP5) to significantly stratify patients into two survival groups across five unrelated tested datasets. According to these findings, low expression of SENP5 is associated with good prognosis among breast cancer patients.Following these findings, we analyzed SENP5 silencing and show it is followed by inhibition of anchorage-independence growth, proliferation, migration and invasion in breast cancer cell lines. We further show that these changes are conducted via regulation of TGFβRI levels. These data relate to recent reports about the SUMOylation of TGFβRI. Following TGFβRI changes in expression, we show that one of its target genes, MMP9, which plays a key role in degrading the extracellular matrix and contributes to TGFβ-induced invasion, is dramatically down regulated upon SENP5 silencing.This is the first report represents SENP5-TGFβ-MMP9 cascade and its mechanistic involvement in breast cancer.  相似文献   
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Objective: To evaluate a Dutch online speech-in-noise screening test (in Dutch: “Kinderhoortest”) in normal-hearing school-age children. Sub-aims were to study test–retest reliability, and the effects of presentation type and age on test results. Design: An observational cross-sectional study at school. Speech reception thresholds (SRTs) were obtained through the online test in a training condition, and two test conditions: on a desktop computer and smartphone. The order of the test conditions was counterbalanced. Study sample: Ninety-four children participated (5–12 years), of which 75 children were normal-hearing (≤25?dB HL at 0.5?kHz,?≤20?dB HL at 1–4?kHz). Results: There was a significant effect for test order for the two test conditions (first or second test), but not for presentation type (desktop computer or smartphone) (repeated measures analyses, F(1,75)?=?12.48, p?F(1,75)?=?0.01, p?=?0.982). SRT significantly improved by age year (first test: 0.25?dB SNR, 95% CI: –0.43 to –0.08, p?=?0.004. Second test: 0.29?dB SNR, 95% CI: –0.46 to –0.11; p?=?0.002). Conclusions: The online test shows potential for routine-hearing screening of school-age children, and can be presented on either a desktop computer or smartphone. The test should be evaluated further in order to establish sensitivity and specificity for hearing loss in children.  相似文献   
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We report for the first time on a case of infertile advance-age patient with large intramural fibroid, who conceived following a course of Ulipristal. The patient underwent two fresh fertility preserving IVF cycles, with cryopreservation of 9?day-3 embryos, followed by a 12?weeks course of Ulipristal (5?mg per day) and a subsequent frozen-thawed embryo transfer with her own previously cryopreserved embryos. We, therefore, believe that Ulipristal is a valuable addition to treatment armamentarium of advance-age infertile patient with prominent intramural fibroid.  相似文献   
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