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排序方式: 共有1231条查询结果,搜索用时 46 毫秒
61.
Catherine B. Stroud Jessica Fitts 《Journal of clinical child and adolescent psychology》2017,46(6):868-879
Research suggests that rumination places adolescents at risk for psychopathology. However, little is known about the association between parenting and rumination. Moreover, relevant theoretical models suggest that parents contribute to the development of rumination both explicitly through their suggestions about how to cope and implicitly through the context of the mother–adolescent relationship. However, prior work has not examined implicit and explicit factors within the same investigation, precluding exploration of their unique and interactive effects. To address these gaps, the present study examined links between mother–adolescent relationship quality, maternal coping suggestions, and adolescent rumination. Participants were early adolescent girls (M age = 12.41 years) and their primary female caregivers. Findings suggested that maternal disengagement suggestions and mother–adolescent relationship quality were each uniquely associated with adolescent rumination. Moreover, the effect of maternal disengagement suggestions depended on the level of maternal engagement suggestions and mother–adolescent relationship quality. Follow-up analyses revealed that these findings were specific to the maladaptive ruminative brooding component of rumination. Future directions for research were elaborated. 相似文献
62.
Lucas H Sampaio Mariane MA Stefani Regiane M Oliveira Ana LM Sousa Greg C Ireton Steven G Reed Malcolm S Duthie 《BMC infectious diseases》2011,11(1):26
Background
Leprosy is a chronic infectious disease caused by Mycobacterium leprae that can manifest a wide variety of immunological and clinical outcomes ranging from potent humoral responses among borderline lepromatous (BL) and lepromatous (LL) patients to strong cellular responses among tuberculoid (TT) and borderline tuberculoid (BT) patients. Until recently, relatively little has been known about the immune responses to individual proteins of M. leprae recognized during leprosy. 相似文献63.
Veins have historically been discussed in qualitative, relative terms: “more compliant” than arteries, subject to “lower pressures”. The structural and compositional differences between arteries and veins are directly related to the different functions of these vessels. Veins are often used as grafts to reroute flow from atherosclerotic arteries, and venous elasticity plays a role in the development of conditions such as varicose veins and valvular insufficiency. It is therefore of clinical interest to determine the elastomechanical properties of veins. In the current study, both tensile and vibration testing are used to obtain elastic moduli of bovine veins. Representative stress–strain data are shown, and the mechanical and failure properties reported. Nonlinear and viscoelastic behavior is observed, though most properties show little strain rate dependence. These data suggest parameters for constitutive modeling of veins and may inform the design and testing of prosthetic venous valves as well as vein grafts. 相似文献
64.
C G Hatjis J P Greelish A D Kofinas A Stroud K Hashimoto J C Rose 《American journal of obstetrics and gynecology》1989,161(4):1015-1019
There is a reduction in intravascular volume in patients with preeclampsia. Since the secretion of atrial natriuretic factor by human atrial myocytes is stimulated by increased intraatrial pressure or atrial distention, we sought to determine whether circulating maternal plasma atrial natriuretic factor concentrations were lower in patients with preeclampsia compared to normal pregnant women. The level of alpha-human atrial natriuretic factor was measured by a specific radioimmunoassay. Maternal venous concentrations of a alpha-human atrial natriuretic factor were higher in patients with severe preeclampsia (116.12 +/- 13.37 pg/ml) than in normal pregnant women (80.30 +/- 4.02 pg/ml). Umbilical artery alpha-human atrial natriuretic factor concentrations were higher in fetuses born to patients with severe preeclampsia (197.68 +/- 29.10 pg/ml) than normal control subjects (118.00 +/- 12.52 pg/ml). Umbilical artery alpha-human atrial natriuretic factor concentrations were higher than umbilical or maternal venous concentrations. In cases of severe preeclampsia, despite the presumed volume changes, maternal atrial natriuretic factor concentrations are higher than in normal pregnant women. The fetus appears to produce its own atrial natriuretic factor. Umbilical artery atrial natriuretic factor concentrations in fetuses born to preeclamptic mothers are higher than those seen in normal control subjects. 相似文献
65.
Sleeping position and sudden infant death syndrome (SIDS): effect of an intervention programme to avoid prone sleeping 总被引:4,自引:0,他引:4
T Markestad B Skadberg E Hordvik I Morild LM Irgens 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(4):375-378
The proportion of prone sleeping among sudden infant death syndrome (SIDS) victims and infants in general, and the rate of SIDS were prospectively studied in the county of Hordaland, Norway, three years before (1987–89) and three years after (1990–92) a campaign to discourage prone sleeping. Before the campaign, 64% of random reference infants were put prone versus 8% after (p < 0.0001). Concurrently, the rate of SIDS decreased from 3.5 to 1.6 per 1000 live births (63 infants before and 30 after the campaign, p = 0.0002). Prone sleeping was not considered a statistically significant risk factor for SIDS before (OR 2.0,95% CI 0.8–4.5), but was highly significant (OR 11.3,95% CI 3.6–36.5) after the campaign. Prone sleeping is an important risk factor for SIDS, but the association may be missed in epidemiological studies if prone is the predominant sleeping position. Behaviour with regard to sleeping position may be changed rapidly by means of a simple campaign. 相似文献
66.
Acute rejection in the elderly recipient: Influence of age in the outcome of kidney transplantation 总被引:7,自引:0,他引:7
Palomar R Ruiz JC Zubimendi JA Cotorruelo JG de Francisco AL Rodrigo E Sanz S Fernández-Fresnedo G Arias M 《International urology and nephrology》2002,33(1):145-148
Since the immune response in older recipientsis weaker they should be less likely to rejecta transplanted organ and should need lessaggressive immunosuppressive treatment. Our aimwas to record the incidence and severity ofepisodes of acute rejection (AR), estimate theinfluence of these events on graft survival ofelderly recipients (60) and to comparethese with that in younger ones.We performed 363 kidney transplants between1/94 and 12/98, and recorded clinical andimmunological data, incidence-severity of ARand cause of graft loss. Patients were dividedinto two groups, according to the age attransplantation: A (<60, n = 281/77.4%) and B( 60, n = 82/22.6%). The percentage ofaging recipients and mean age of donors andrecipients increased throughout the period.Although the incidence of ATN was higher in theolder group (29% vs.19%, p < 0.0001) thenumber of graft biopsies was equal in bothgroups. The incidence of AR was similar, 33.4%vs. 26.8%, pNS. The number of AR episodes perpatient was 0.44 and 0.41 respectively. Theseverity of AR was: Banff grade I: A (40.3%)/B (45.7%) pNS; grade II: A (44.1%)/B(48.57) pNS; grade III: A (15.5%)/B (5.7%)pNS. Younger recipients presented a higherlevel of panel-reactive antibodies (PRA) (4.3%vs. 2.07%, p = 0.01). One-year patient survivalwas 96%/91% (p<0.05) and graft survivalwas 81%/78% (pNS) respectively.The age of recipient does not seem to haveinfluenced the incidence-severity of AR or thegraft survival. Thus immunosuppression shouldbe individualised for each patient and shouldnot depend on the age at transplantation. 相似文献
67.
Structure of tRNA pseudouridine synthase TruB and its RNA complex: RNA recognition through a combination of rigid docking and induced fit 下载免费PDF全文
68.
Wang LM Zhang Q Zhu W He C Lu CL Ding DF Chen ZY 《第二军医大学学报》2005,26(11):1299-1299
Glial cell line-derived neurotrophic factor (GDNF) plays a critical role in neurodevelopment and survival of midbrain dopaminergic and spinal motor neurons in vitro and in vivo. The biological actions of GDNF are mediated by a two-receptor complex consisting of a glycosylphosphatidylinositol-linked cell surface molecule, the GDNF family receptor alpha 1 (GFR alpha 1), and receptor protein tyrosine kinase Ret. Although structural analysis of GDNF has been extensively examined, less is known about the structural basis of GFR alpha 1 function. In this study, based on evolutionary trace method and relative solvent accessibility prediction of residues, a set of trace residues that are solvent-accessible was selected for site-directed mutagenesis. A series of GFR alpha 1 mutations was made, and PC12 cell lines stably expressing different GFR alpha 1 mutants were generated. According to the survival and differentiation responses of these stable PC12 cells upon GDNF stimulation and the GDNF- GFR alpha 1-Ret interaction assay, residues 152NN153, Arg259, and 316SNS318 in the GFR alpha 1 central region were found to be critical for GFR alpha 1 binding to GDNF and eliciting downstream signal transduction. The single mutation R259A in the GFR alpha 1 molecule simultaneously lost its binding ability to GDNF and Ret. However N152A/N153A or S316A/N317A/ S318A mutation in the GFR alpha 1 molecule still retained the ability to bind with Ret. These findings suggest that distinct structural elements in GFR alpha 1 may be involved in binding to GDNF and Ret. 相似文献
69.
CJT De Amorim e Silva A Mackenzie LM Hallowell SE Stewart MR Ditchfield 《Journal of Medical Imaging and Radiation Oncology》2006,50(4):319-323
The aim of this study was to evaluate the effectiveness of a practice magnetic resonance unit, in preparing children to undergo magnetic resonance procedures without general anaesthesia (GA) or sedation. The records of children who attended the practice MRI between February 2002 and April 2004 were retrospectively reviewed. Each record was assessed as to whether the child had passed or failed the practice MRI intervention. Those children who were considered to have passed and were proceeded to a clinical non‐GA MRI had the report of the clinical scan reviewed. If the scan had been reported as non‐diagnostic because of movement artefact it was classified as a failed scan, otherwise it was considered a pass. One hundred and thirty‐four children undertook a practice MRI (age range 4.1–16.1 years, median age 7.7 years, 47% boys) and 120/134 (90%) passed the practice session. In all, 117/120 (98%) subsequently had a clinical non‐GA MRI and 110/117 (94%) passed (median age 7.8 years, 47% boys). Preparation is a safe and effective method to reduce the need for sedation and GA in children undergoing a clinical MRI scan. It provides a positive medical experience for children, parents and staff, and results in cost savings for the hospital. 相似文献
70.