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1.
Mitch Ricketts James Shanteau Breeanna McSpadden Kristen M. Fernandez-Medina 《Social science & medicine (1982)》2010
After 14 years of rising death rates due to unintentional injuries in the U.S., it is time to ask how safety messages can be redesigned to have a greater impact on risky behavior. To this end, many researchers have called for a new, narrative approach to prevention messages—based on persuasive stories about people who have suffered injuries and illnesses in the past. Still, there is scant evidence that story-based communications are more effective than equivalent non-narrative messages at changing actual (rather than self-reported) safety and health behavior. Our research examined the impact of injury stories on actual safety behavior in a controlled experimental setting at a US university. Teams of participants assembled a product (a child's swing) using written instructions. The instructions contained safety messages targeting assembly mistakes that have been linked to serious injuries in children who play on swings. Participant teams were randomly assigned to three conditions: assembly instructions containing story-based safety messages, instructions with concrete (but non-anecdotal) safety messages, and instructions with traditional abstract safety messages. After adjustment for covariates, story-based messages resulted in a 19 percent improvement in safety behavior, compared with non-narrative communications. Importantly, injury stories did not create undue fear of the message object, demonstrating that brief anecdotes about accident victims can convince people to take reasonable precautions without creating unwarranted alarm about risks. 相似文献
2.
Background
Taxometric methods were used to discern the latent structure of cannabis dependence. Such methods help determine if a construct is categorical or dimensional. Taxometric analyses (MAXEIG and MAMBAC) were conducted on data from 1,474 cannabis-using respondents to the 2001–2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Respondents answered questions assessing DSM-IV criteria for cannabis dependence. 相似文献3.
P. E. Lønning M. Dowsett A. Jones D. Ekse S. Jacobs F. McNeil D. C. Johannessen T. J. Powles 《Breast cancer research and treatment》1992,23(1-2):57-62
Summary The clinical and biochemical effects of combined treatment with the two aromatase inhibitors aminoglutethimide and 4-hydroxyandrostenedione were evaluated in 10 patients suffering from advanced breast cancer. All patients had become resistant to treatment with one of the drugs before having combined treatment. Seven patients progressing on 4-hydroxyandrostenedione who had aminoglutethimide added to their treatment and achieved a further suppression of plasma oestradiol by a mean of 40.0% (p<0.05). Plasma oestrone was suppressed by a mean of 40.6% (p<0.025) and plasma oestrone sulphate was suppressed by a mean of 63.6% (p<0.025). Two of the patients, neither of whom had responded to 4-hydroxyandrostenedione alone, experienced objective tumour regression when aminoglutethimide was given in concert. Three patients progressing on aminoglutethimide who had 4-hydroxyandrostenedione added showed no further suppression of their plasma oestrogen levels, and no tumour regression was observed. These findings suggest a dose-response relationship between plasma oestrogen suppression at low postmenopausal levels and objective tumour response in breast cancer. 相似文献
4.
F. A. MacNeill S. Jacobs M. Dowsett P. E. Lonning T. J. Powles 《Cancer chemotherapy and pharmacology》1995,36(3):249-254
This study investigated the influence of the aromatase inhibitor 4-hydroxyandrostenedione (4OHA, formestane), given orally, on peripheral aromatase activity and plasma oestradiol (E
2) levels in post-menopausal women with advanced breast cancer. The aim was to establish whether an optimal dose could be identified that had a pharmacological effectiveness comparable with that of parenteral 4OHA. A total of 13 post-menopausal women were studied before treatment and after a minimum of 4 weeks on treatment with one or more of the following doses: 125 mg once daily (od), 125 mg b.i.d. (bd) and 250 mg od. In all, seven aromatase studied were performed at 125 mg od; four, at 125 mg bd; and ten, at 250 mg od. Three patients were studied at all doses. E2 was measured concurrently and was available at all dose increments for seven patients. Given at doses of 125 mg od, 125 mg bd and 250 mg od, treatment with formestane inhibited in vivo aromatisation by 62.3%±9.5%, 70.0%±5.1% and 57.3%±5.3%, respectively (mean±SEM). Corresponding values for plasma E2 suppression were 30.7%±6.5%, 43.4%±4.5% and 42.9%±6.7%, respectively. Thus, apart from a somewhat better suppression of plasma E2 levels by the two higher doses as compared with 125 mg od, no significant difference in the degree of aromatase inhibition or plasma E2 suppression was observed. The suppression of E2 by oral 4OHA at 125 mg bd or 250 mg od approaches that achieved by the recommended parenteral schedule of 250 mg fortnightly, but inhibition of aromatase at this dose was substantially inferior. The findings are consistent with a hypothesis that 4OHA given orally may cause substantial plasma oestrogen suppression during part of the day, but neither the od nor the bd regimens investigated in the present study were capable of producing optimal aromatase inhibition. 相似文献
5.
William E Mitch 《Journal of renal nutrition》2007,17(1):66-69
Patients with chronic kidney disease (CKD), including those who are treated with hemodialysis, frequently develop hypoalbuminemia and a decrease in body weight. These abnormalities are usually attributed to malnutrition, but true malnutrition (ie, a disorder due to an abnormal diet) is rarely the mechanism causing decreased protein stores. Hypoalbuminemia is closely related to evidence of inflammation, and a decrease in muscle mass is caused by activation of muscle protein breakdown. In uremic rodents and patients, the initial step in the loss of muscle protein is activation of caspase-3, which cleaves the complex structure of muscle to provide substrates for the ubiquitin-proteasome pathway (UPP). The activity of caspase-3 can be detected by the presence of a characteristic 14-kDa actin fragment in the insoluble fraction of a muscle biopsy specimen. Abnormalities in cell signaling activate caspase-3 and the UPP; a key abnormality is decreased activity in the phosphatidylinositol-3-kinase/Akt pathway, leading to activation of caspase-3 and a specific E3 ubiquitin conjugating enzyme, atrogin-1/MAFbx. Inflammatory cytokines also represent a potential cell signaling abnormality that activates muscle protein breakdown, possibly because cytokines activate the E3 ubiquigin conjugating enzyme, MuRF1. An understanding of these pathways could help the clinician to identify therapeutic targets for preventing loss of muscle protein. 相似文献
6.
7.
New Latex Bead Agglutination Assay for Differential Diagnosis of Cattle Infected with Mycobacterium bovis and Mycobacterium avium subsp. paratuberculosis
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Hye Cheong Koo Yong Ho Park Jongsam Ahn W. Ray Waters Mary Jo Hamilton George Barrington Abdelaziz A. Mosaad Mitch V. Palmer Sang Shin William C. Davis 《Clinical and Vaccine Immunology : CVI》2004,11(6):1070-1074
Extensive studies have shown that the current assays used to identify cattle infected with Mycobacterium bovis or Mycobacterium avium subsp. paratuberculosis are not sufficiently sensitive and specific to detect all infected animals, especially animals recently infected with the pathogens. In the present report we show that these limitations might be overcome with a latex bead agglutination assay (LBAA). With the specific immunodominant epitope (ESAT6-p) of M. bovis, we developed an LBAA and enzyme immunoassay (EIA) for that purpose and compared them with the “gold standard” culture method and skin test for their efficacy in detecting bovine tuberculosis. When sera from control healthy cows (n = 10), M. avium subsp. paratuberculosis-positive cattle (naturally infected, n = 16; experimentally infected, n = 8), and M. bovis-positive cattle (naturally infected, n = 49;experimentally infected, n = 20) were applied to an EIA and an LBAA developed with ESAT6-p, the two tests showed similar sensitivity (97.1% by EIA, 95.7% by LBAA), high specificity (94.2% by EIA, 100% by LBAA), and a positive correlation (kappa value, 0.85; correlation rate, 93.2%; correlation coefficient, 0.64). Receiver operating characteristic analysis of EIA results and comparison with the culture method determined a suitable cutoff value at 0.469, with an area under the curve of 0.991 (95% confidence interval, 0.977 to 1.0). As LBAA didn't show any positive reactions with sera from uninfected control cows or M. avium subsp. paratuberculosis-infected cattle, which were confirmed to be free of M. bovis by culture or PCR, LBAA using the ESAT6-p can be a rapid and useful M. bovis diagnostic assay. The data suggest that rapid, sensitive, and specific assays can be developed with peptides containing immunodominant epitopes present in proteins uniquely expressed in M. bovis or M. avium subsp. paratuberculosis for differential diagnosis of cattle infected with M. bovis or M. avium subsp. paratuberculosis. 相似文献
8.
Michael Bilous Mitch Dowsett Wedad Hanna Jorma Isola Annette Lebeau Aberlardo Moreno Frédérique Penault-Llorca Josef Rüschoff Gorana Tomasic Marc van de Vijver 《Modern pathology》2003,16(2):173-182
Knowledge of HER2 status is a prerequisite when considering a patient's eligibility for Herceptin (trastuzumab) therapy. Accurate assessment of HER2 status is essential to ensure that all patients who may benefit from Herceptin are correctly identified. There are several assays available to determine HER2 status: the most common in routine clinical practice are immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Various factors can affect the results achieved with these assays, including the assay antibody/probe, the methodology and the experience of personnel. Many countries have implemented national testing guidelines in an attempt to standardize testing procedures and make results more accurate. These guidelines vary in the level of detail and the number of recommendations. This review looks at areas of consensus between the different national testing guidelines and highlights where errors may arise during the testing procedure. The key point underlined by this review is that whatever method is used to test for HER2 status, the technology must be validated first, and there must be regular internal and external quality control and quality assurance procedures. 相似文献
9.
The effect of a keto acid-amino acid supplement to a restricted diet on the progression of chronic renal failure 总被引:4,自引:0,他引:4
W E Mitch M Walser T I Steinman S Hill S Zeger K Tungsanga 《The New England journal of medicine》1984,311(10):623-629
We treated 24 patients who had chronic renal failure with a low-phosphorus diet containing 20 to 30 g of mixed-quality protein, supplemented by amino acids and their keto analogues. Seventeen patients had well-defined rates of progression before treatment, as assessed by serial determinations of serum creatinine levels. By extrapolating these rates of progression, we found that 10 of the 17 (59 per cent) had a clinically important slower rise in creatinine levels during long-term treatment (average, 20 months) than predicted; none had a faster rise than predicted. Seven of the 17 patients began treatment before creatinine reached the level of 8 mg per deciliter; in six of the seven, followed for an average of 22 months, creatinine has remained at or below the level at the start of treatment. Nutrition, as assessed by body weight, nitrogen balance, serum albumin, and serum transferrin, has been well maintained. This regimen slowed or arrested the rise in creatinine levels and thus must have slowed or halted the progression of renal insufficiency in a majority of cases, especially when treatment was initiated before creatinine had reached the level of 8 mg per deciliter. The mechanism underlying this effect remains to be determined. 相似文献
10.
Jane S Chen Mitch Matoga Brian W Pence Kimberly A Powers Courtney N Maierhofer Edward Jere Cecilia Massa Shiraz Khan Sarah E Rutstein Sam Phiri Mina C Hosseinipour Myron S Cohen Irving F Hoffman William C Miller Kathryn E Lancaster 《Journal of the International AIDS Society》2021,24(4)
IntroductionHIV diagnosis is the necessary first step towards HIV care initiation, yet many persons living with HIV (PLWH) remain undiagnosed. Employing multiple HIV testing strategies in tandem could increase HIV detection and promote linkage to care. We aimed to assess an intervention to improve HIV detection within socio‐sexual networks of PLWH in two sexually transmitted infections (STI) clinics in Lilongwe, Malawi.MethodsWe conducted a randomized controlled trial to evaluate an intervention combining acute HIV infection (AHI) screening, contract partner notification and social contact referral versus the Malawian standard of care: serial rapid serological HIV tests and passive partner referral. Enrolment occurred between 2015 and 2019. HIV‐seropositive persons (two positive rapid tests) were randomized to the trial arms and HIV‐seronegative (one negative rapid test) and ‐serodiscordant (one positive test followed by a negative confirmatory test) persons were screened for AHI with HIV RNA testing. Those found to have AHI were offered enrolment into the intervention arm. Our primary outcome of interest was the number of new HIV diagnoses made per index participant within participants’ sexual and social networks. We also calculated total persons, sexual partners and PLWH (including those previously diagnosed) referred per index participant.ResultsA total of 1230 HIV‐seropositive persons were randomized to the control arm, and 561 to the intervention arm. Another 12,713 HIV‐seronegative or ‐serodiscordant persons underwent AHI screening, resulting in 136 AHI cases, of whom 94 enrolled into the intervention arm. The intervention increased the number of new HIV diagnoses made per index participant versus the control (ratio: 1.9; 95% confidence interval (CI): 1.2 to 3.1). The intervention also increased the numbers of persons (ratio: 2.5; 95% CI: 2.0 to 3.2), sexual partners (ratio: 1.7; 95% CI: 1.4 to 2.0) and PLWH (ratio: 2.3; 95% CI: 1.7 to 3.2) referred per index participant.ConclusionsCombining three distinct HIV testing and referral strategies increased the detection of previously undiagnosed HIV infections within the socio‐sexual networks of PLWH seeking STI care. Combination HIV detection strategies that leverage AHI screening and socio‐sexual contact networks offer a novel and efficacious approach to increasing HIV status awareness. 相似文献