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61.

Background  

The recent increase in childhood obesity is expected to add significantly to the prevalence of chronic diseases. We used multivariate multilevel analysis to examine associations between parks/green space and childhood overweight/obesity across communities in Calgary, Canada, a city characterized by intensified urban sprawl and high car use.  相似文献   
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Purpose

Pilot trials inform the design and conduct of larger scale trials. Using the Consolidated Standards of Reporting Trials (CONSORT) pilot extension guidelines, we assessed reporting quality in five high-impact anesthesia journals and explored factors associated with reporting quality.

Methods

The five highest-impact anesthesia journals were screened for randomized-controlled trials published as pilot or feasibility trials between 2006 and 2016. A pair of reviewers independently screened citations, extracted data, and assessed reporting quality using the CONSORT pilot trial extension checklists for abstracts and full texts. We reported the percentage adherence for each item, along with the median [interquartile range (IQR)] or mean (standard deviation [SD]) for all items. The factors considered to influence reporting were: 1) trial registration, 2) industry funding, 3) trial identification as a pilot or feasibility in the title or abstract, 4) primary objective as “feasibility”, and 5) the specific journal. The association was estimated using generalized estimating equations and reported as incidence rate ratios with 99% confidence intervals.

Results

Of 364 citations, 58 articles were eligible. The median [IQR] number of CONSORT abstract items reported was 5 [4-7], and the mean (SD) number of full text items reported was 13 (5). Significantly poor reporting was associated with “not registering the trial” (both abstracts and full texts), “trial not identified as a pilot” (abstracts), and “using clinical hypothesis as the primary objective” (full texts).

Conclusion

The reporting quality of pilot trials published in leading anesthesia journals is poor. Journal editorial boards can encourage improved reporting by supporting adherence to the CONSORT extension for pilot trials.
  相似文献   
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The use of prednisolone and prednisone is prohibited by the World Anti‐Doping Agency (WADA) due to their performance‐enhancing effect. The purpose of the present work was to explore the possibility of identification and detection of various metabolites of prednisolone by liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) in excretion study samples. Ten metabolites of prednisolone could be identified namely prednisone (11‐oxo metabolite) [M‐1], 6‐β‐OH‐prednisolone [M‐2], 20‐β‐OH‐prednisolone [M‐3], 20‐α‐OH‐prednisolone [M‐4], 20‐α‐OH‐prednisone [M‐5], 20‐β‐OH‐prednisone [M‐6], 2 tetrahydro epimers of 20‐β‐OH‐prednisolone [M‐7], 2 tetrahydro epimers of 20‐α‐OH‐prednisolone [M‐8], 2 tetrahydro epimers of 20‐β‐OH‐prednisone [M‐9], and 2 tetrahydro epimers of 20‐α–OH‐prednisone [M‐10]. Prednisolone was administered in 10‐, 20‐, and 40‐mg dosage to healthy volunteers to study detection of various metabolites. The parent, M‐1, M‐2, and M‐3 could be detected up to 72 h while rest of the metabolites were detectable up to 24 h after drug administration. The detection of newer metabolites of the drug can further be used for confirmatory purposes. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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The aim of the present study was to formulate and evaluate pharmaceutically equivalent injectable aqueous suspension for parenteral depot of methyl prednisolone acetate. Various aqueous suspensions were prepared by rapid stirring and colloid milling method. The prepared aqueous suspensions were subjected to particle size determination, sedimentation study, in vitro release studies (pH dependent dissolution study), and stability studies. The optimized formulation consisted of 4% w/w of methyl prednisolone acetate, 2.91% w/w of PEG-3350, 0.19% w/v of injection grade Tween-80, 0.68% w/w of monobasic sodium phosphate, 0.15% w/w of di-basic sodium phosphate, 0.91% w/v of benzyl alcohol, 0.32% w/w sodium meta bisulphate. The f2 value was calculated for innovator (DepoMedrol®, Batch No. MPH-0254) and optimized formulation at pH 6.8 and pH 7.4 phosphate buffers. The f2 values of 62.94 and 54.37 were obtained at pH 6.8 and pH 7.4 phosphate buffers respectively. The particle size ranged 23-27 μm at D value of 0.9 for both test and innovator product.  相似文献   
66.

Objective:

The use of performance enhancing substances is banned in sports by the World Anti-Doping Agency (WADA). Though most prohibited substances can be detected by GC/MS, inclusion of corticosteroids and designer drugs has made it essential to detect these critical doping agents on LC/MS/MS due to their better separation and detection.

Materials and Methods:

A common extraction procedure for the isolation of acidic, basic and neutral drugs from urine samples was developed. A total of 28 doping drugs were analyzed on API 3200 Triple quadrupole mass spectrometer using C18 column in atmospheric pressure electrospray ionization. The mobile phase composition was a mixture of 1% formic acid and acetonitrile with gradient time period.

Results:

The method developed was very sensitive for detection of 28 doping agents. The linearity was performed for each drug and the total recovery percentage ranged from 57 to 114. Limit of detection is found to be 0.5 ng/ml for carboxy finasteride and 1-5 ng/ml for other drugs. The method was successfully used to detect positive urine samples of 3-OH-stanozolol, methyl phenidate, mesocarb, clomiphene metabolite and carboxy finasteride.

Conclusion:

The method developed based on controlled pH extraction method and HPLC-mass spectrometry analysis allowed better identification and confirmation of glucocorticosteroids and a few other drugs in different categories. The validated method has been used successfully for testing of 1000 In-competition samples. The method helped in detection of chemically and pharmacologically different banned drugs in urine in a single short run at a minimum required performance limit set by WADA.  相似文献   
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Rewired ERK-JNK signaling pathways in melanoma   总被引:3,自引:0,他引:3  
  相似文献   
70.
BACKGROUND: Uncertainties continue to exist concerning the outcomes and management of small (T1a/b N0 M0) invasive breast cancers. METHODS: A central pathology review was performed of 638 such lesions from National Surgical Adjuvant Breast and Bowel Project (NSABP) clinical trial B-21. RESULTS: Univariate analysis revealed a high risk for ipsilateral breast tumor recurrence with tumors exhibiting a ductal carcinoma in situ component or poor nuclear grade. The converse (protective effect) was found with tumors arising in radial scars, those of tubular histologic type, and those with moderate/marked tumor stroma. The correlations were generally similar for disease-free survival. However, only nuclear grade was found to be independently significant for both of these outcomes. Only lymphatic tumor extension was univariately and multivariately significant for overall survival. CONCLUSIONS: The long-term results of follow-up (median, 11.2 years) from the current trial continue to support the need for local breast irradiation and adjuvant therapy in the management of patients with these small cancers.  相似文献   
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