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11.
The association between stress and health has been well researched in the past; however, comparatively few mediators have been tested to understand the underlying mechanism. With increasing awareness on mental well‐being, this study evaluated the relationship between perceived stress and perceived health and examined mental well‐being as a mediator. Two‐hundred undergraduates aged 21 to 26 years completed the English Perceived Stress Scale, Health Status Questionnaire and Asian Mental Well‐Being Scale that assess perceived stress, perceived health and mental well‐being, respectively. Factor analysis and structural equation modelling on the Perceived Stress Scale replicated the reported two‐factor structure after excluding an insignificant item. Linear multiple regression analyses indicated that perceived stress was negatively associated with perceived health. Results showed that mental well‐being partially mediated the relationship between perceived stress and perceived health, although it is acknowledged that this association could be bidirectional. Findings from the present study suggest that future research could focus on reducing stress and improving mental well‐being to alleviate the effect of stress on health. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
12.
We investigated the prostate cancer detection rates upon transrectal ultrasound (TRUS)-guided biopsy in relation to digital rectal examination (DRE) and prostate-specific antigen (PSA), and risk factors of prostate cancer detection in the Chinese population. Data from all consecutive Chinese men who underwent first TRUS-guided prostate biopsy from year 2000 to 2013 was retrieved from our database. The prostate cancer detection rates with reference to DRE finding and PSA level of < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 were investigated. Multivariate logistic regression analyses were performed to investigate for potential risk factors of prostate cancer detection. A total of 2606 Chinese men were included. In patients with normal DRE, the cancer detection rates were 8.6%, 13.4%, 21.8%, 41.7% and 85.2% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. In patients with abnormal DRE, the cancer detection rates were 12.4%, 30.2%, 52.7%, 80.6% and 96.4% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. Older age, smaller prostate volume, larger number of biopsy cores, presence of abnormal DRE finding and higher PSA level were associated with increased risk of prostate cancer detection upon multivariate logistic regression analyses (P < 0.001). Chinese men appeared to have lower prostate cancer detection rates when compared to the Western population. Taking the different risk factors into account, an individualized approach to the decision of TRUS-guided biopsy can be adopted.  相似文献   
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Eosinophils stimulate fibroblast DNA synthesis   总被引:9,自引:0,他引:9  
Pincus  SH; Ramesh  KS; Wyler  DJ 《Blood》1987,70(2):572-574
Fibrosis complicates a number of chronic inflammatory diseases and occurs in some conditions following chronic hypereosinophilic syndromes. We assessed whether eosinophils might be a source of fibrogenic factors. Extracts of human and guinea pig cell populations enriched for eosinophils contained substances that stimulated tritiated thymidine incorporation by human fibroblasts. Supernatants derived from resting eosinophils and extracts prepared from eosinophil granules also contained fibrogenic factors. Our findings demonstrate a new potential role for eosinophils and suggest a causal relationship between tissue eosinophilia and scar formation in certain parasitic conditions.  相似文献   
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BackgroundRecruiting participants to clinical research studies is challenging, especially when conducted in safety net settings. We sought to compare the efficacy of different recruitment strategies in an NIH-funded study assessing treatment burden in patients with multiple chronic conditions (MCCs).MethodsTargeted mailing, in-person table-based recruitment (“tabling”) in the waiting room, and telephone calling were used to enroll subjects into one of two studies of treatment burden: a survey study to validate a brief measure of treatment burden for quality assessment (study 1) or a qualitative study to develop a treatment burden clinical communication tool (study 2).ResultsOver 50% of subjects in each study were African American or African immigrants. In study 1, the enrollment goal of 200 was reached within 4 months. Tabling enrolled 78.5% of patients, while the remainder (21.5%) were enrolled from phone calls to eligible patients identified through the electronic medical record (EMR). In study 2, 340 eligible patients were identified through the EMR, and 7 (2.1%) were successfully enrolled via mailed invitations and responses. Retention rates (66% in study 1 and 71% in study 2) were reasonable in all groups.ConclusionsStudy recruiting goals in our safety net population were rapidly reached using the tabling method, which had substantively higher enrollment rates than mailings or telephone calls based on EMR reports. Future trials could compare recruitment strategies across settings and clinical populations.  相似文献   
18.
Experiments performed in our laboratory, using electrical stimulation combined with microinjection of drugs in the dorsal midbrain central grey (CG) of the rat, evidenced that direct stimulation of GABA receptors with locally administered gamma-aminobutyric acid (GABA) or the GABAA receptor agonists 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol, isoguvacine and muscimol raised the aversive threshold, defined as the lowest electrical current intensity inducing flight or escape behaviour when applied to the dorsal CG. The GABAB receptor agonist baclofen was ineffective. Also, enhancement of endogenous GABA action through local injection of the benzodiazepines chlordiazepoxide and midazolam or of pentobarbital resulted in anti-aversive effects. Ro 15-1788 antagonized both chlordiazepoxide and midazolam, suggesting benzodiazepine receptor mediation. In contrast to pro-GABAergic drugs, microinjection of the GABA antagonists bicuculline and picrotoxin into the CG elicited flight behaviour, like the electrical stimulation. Similar experiments with drugs influencing serotonergic neurotransmission evidenced that intra-CG microinjection of serotonin (5-HT) or of the direct 5-HT receptor agonist 5-methoxy-N,N-dimethyltryptamine increased the aversive threshold. The anti-aversive effect of 5-HT was potentiated by the selective inhibitor of 5-HT neuronal uptake, zimelidine. Also, the latter drug increased the aversive threshold when given alone. The anti-aversive effect of 5-HT was antagonized by local pretreatment with either metergoline or ketanserin, the latter being a selective blocker of 5-HT2 receptors. In contrast to the GABA antagonists mentioned above, the 5-HT receptor blockers did not evoke aversive behaviour per se. Therefore, both GABAergic and serotonergic mechanisms are likely to play an inhibitory role in the dorsal CG integrating aversive behaviour.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
19.
Vesico-ureteric reflux: occurrence and long-term risks   总被引:1,自引:0,他引:1  
The prevalence of vesico-ureteric reflux in the general population is unknown, but it is increased in risk groups, such as children with symptomatic urinary tract infection, schoolgirls with asymptomatic bacteriuria, first-degree relatives of patients with reflux and children with prenatal dilatation of their upper urinary tract. Children and adults with pyelonephritic renal scarring are at risk of serious long-term complications, e.g. hypertension and renal failure. Modern paediatric care, with early detection and treatment of urinary tract infections and reflux during childhood and adolescence, may improve long-term prognosis. In the adult patient with established pyelonephritic renal scarring, careful control of hypertension may retard the rate of progression, and angiotensin converting enzyme inhibitors may have renal protective properties.  相似文献   
20.
Aim: Findings of hypoxia prior to death and involvement of a dysregulation of the serotonergic network in sudden infant death syndrome (SIDS) may indicate that brain‐derived neutrophic factor (BDNF) also is of importance with regard to sudden unexpected infant death. Based on this, the purpose of this study was to investigate the BDNF val66met polymorphism in SIDS cases, cases of infectious death and controls. Methods: The polymorphism was investigated in 163 SIDS cases, 34 cases of infectious death and 121 controls, using real‐time PCR and fluorescence melting curve analysis. Results: There were no differences in val66met genotype distribution between neither the SIDS cases nor the cases of infectious death and controls (p = 0.95 and p = 0.52, respectively). Conclusion: The study indicates that the val66met polymorphism is not important for sudden unexpected infant death. However, several other SNPs in the BDNF gene, as well as in other genes involved in this pathway, including G‐protein, have to be investigated to fully exclude any involvement of BDNF in SIDS.  相似文献   
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