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51.
For most experimental and therapeutic applications of gene transfer, regulation of the timing and level of gene expression is preferable to constitutive gene expression. Among the systems that have been developed for pharmacologically controlled gene expression in mammalian cells, the bacterial tetracycline (tet)-responsive system has the advantage that it is dependent on a drug (tet) that is both highly specific and non-toxic. The tet-responsive system has been previously used to modulate expression of cell cycle regulatory proteins in cultured cells, reporter genes in plants and transgenic mice and reporter genes directly injected into the heart. Here we show that orally or parenterally administered tet regulates expression of tet-responsive plasmids injected directly into mouse skeletal muscle. Reporter gene expression was suppressed by two orders of magnitude in the presence of tet, and that suppression was reversed when tet was withdrawn. These data show that skeletal muscle offers an accessible and well characterized target tissue for tet-controlled expression of genesin vivo, suggesting applications to developmental studies and gene therapy.  相似文献   
52.
A prospective, randomized trial is described in which the usefulness of two tests in the control of anticoagulant therapy is compared. Fifty-two patients were controlled by the one-stage prothrombin time and 55 by the activated partial thromboplastin time. There was no significant difference in the incidence of bleeding between the two groups. When bleeding did occur, it was more often reflected by prolongation of the prothrombin time than of the activated partial thromboplastin time. The prothrombin time was found to have some practical advantages over the activated partial thromboplastin time.  相似文献   
53.
Prerequisites for translating intervention research findings into practice are maintenance of results, generalization of effects and consistency of implementation. This report presents 12 months follow-up information on a randomized 2x2 factorial trial evaluating the incremental effects of adding (1) telephone follow-up or (2) a community resources utilization component to a basic touchscreen computer-assisted dietary goal-setting intervention for 320 type 2 diabetes patients. All conditions evidenced significant improvement from baseline to the 12 months follow-up across behavioral, biological and psychosocial measures. There were few consistent differences between conditions, but results were robust across interventionists and clinics. The telephone follow-up component appeared to enhance long-term results on some measures. When considered along with earlier results from a randomized trial that included a control condition without goal setting, it is concluded that this basic goal-setting intervention can be consistently implemented by a variety of interventionists and produce lasting improvements.  相似文献   
54.
This study examined risk and protective factors that differentiate low-income, abused African American women (N = 200) who attempted suicide from those who had never made a suicide attempt. Results from multivariate analyses revealed that numerous and/or severe negative life events, a history of child maltreatment, high levels of psychological distress and depression, hopelessness about the future, and alcohol and drug problems were factors associated with attempter status. Protective factors associated with nonattempter status included hopefulness, self-efficacy, coping skills, social support, and effectiveness in obtaining material resources. Culturally competent intervention approaches for abused women should target increasing their protective factors and reducing their risk factors to decrease the likelihood that these women engage in suicidal behavior.  相似文献   
55.
This study examined the physiological response (skin conductance and heart rate [HR]) of youth exposed to a mildly phobic stimulus (video of a large dog) and its relation to child- and parent-reported anxiety symptoms and cognitive bias in a community-recruited sample of youth (n = 49). The results of this study indicated that HR and skin-conductance response were associated with youth report but not parent report of their child's symptoms of anxiety disorders and that HR response was more strongly associated with anxiety symptoms than skin-conductance response. Physiological response was uniquely associated with youth-reported symptoms of anxiety rather than youth-reported depression. Finally, HR response interacted with cognitive bias in predicting childhood anxiety disorder symptoms in a manner consistent with theories of the etiology of anxiety disorders.  相似文献   
56.
Out-of-hours organisations are responsible for the care of patients 70% of the time, and their GPs act as gatekeepers to secondary care services. This observational study identifies the variations in GPs' out-of-hours referral rates to secondary care and factors that could explain these variations. One hundred and forty-nine GPs who worked in one UK general practice out-of-hours cooperative which served 19 practices with 167 000 registered patients. Data on patients who accessed the out-of-hours service over 3 years (2001-2004) were examined. Factors thought to be predictors of variation in referral rates were investigated using logistic regression analysis. There was a fivefold difference in referral rates between the lowest and highest referring quartiles of GPs (OR [odds ratio] = 4.56, CI [confidence interval] = 3.86 to 5.38). The sex (female) of the clinician, the time of the consultation (11 pm to 7 am), and the place of the consultation (home visit) accounted for some, but not all, of the increased referral rates. A doctor working out-of-hours disproportionately influences the fate of the patient, the number of hospital admissions, and extra costs to the health service. There is a need for follow-up studies to investigate the factors associated with referral behaviour, and how the variation relates to patient factors and the resources available. These findings could be used when planning the staffing of out-of-hours services to optimise appropriate care and minimise patients' exposure to unnecessary intrusive and expensive hospital care.  相似文献   
57.
Mode of delivery and risk of developing allergic disease   总被引:3,自引:0,他引:3  
The aim of this study was to quantify the relationship between mode of delivery and subsequent incidence of allergic disease. The analysis is based on data derived from a birth cohort of 24,690 children who contributed data to the West Midlands General Practice Research Database. We found no convincing evidence to suggest that babies born by caesarean, forceps, or breech delivery had an increased risk of developing allergic disease.  相似文献   
58.
We have developed small-volume (50 or 250 μl)-format branched-DNA assays for human immunodeficiency virus type 1 (HIV-1) RNA for use with specimens in which the volume is limited and/or a high viral load is anticipated. These formats exhibited good correlation with the standard 1-ml format; high specificity, reproducibility, and linearity; and no significant difference in the quantification of HIV-1 subtypes.  相似文献   
59.
Polymorphonuclear leukocytes (PMNs; commonly known as neutrophils) play essential roles in innate immunity and inflammation. Although there are standardized methods for the isolation of human neutrophils, they are time consuming and demand considerable technical expertise, making them unfeasible for many clinical applications. Here, we describe a simple and time-efficient technique for the isolation of human neutrophils, which adapts a readily available commercial cell preparation tube (CPT) currently in use for isolation of peripheral blood mononuclear cells (PBMC) and plasma and is now adapted to also yield neutrophils. The total time required for neutrophil isolation was less than 1 hr. Neutrophils isolated by this method were highly purified (> or =97%) as assessed by surface expression of the neutrophil specific marker, CD66b. Neutrophils isolated by this method were functional as demonstrated by their ability to secrete interleukin-1 receptor antagonist (IL-1RA). Neutrophils isolated using this new technique secreted significant amounts of soluble IL-1RA (929.3+/-197 pg/10(6)cells/mL) in response to lipopolysaccharide (LPS). Use of this adapted CPT method allows simultaneous isolation of functional human neutrophils as well as PBMC and plasma. Adoption of this new method will allow the conduct of different neutrophil assays at any clinical site without requiring trained laboratory personnel or a large staff time commitment.  相似文献   
60.
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