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61.
K A Steingold L Laufer R J Chetkowski J D DeFazio D W Matt D R Meldrum H L Judd 《The Journal of clinical endocrinology and metabolism》1985,61(4):627-632
A randomized prospective double blind study was performed to assess the ability of a transdermal therapeutic system (TTS) delivering estradiol (E2) to suppress hot flashes (HFs) in symptomatic postmenopausal women. Patients were given placebo or E2 in four doses for a 20-day period, and serum gonadotropin and estrogen levels and the occurrences of HFs were measured. Administration of placebo had no measurable effect on either estrogen or gonadotropin levels or the occurrence of HFs. A dose-response relationship was found between the rate of E2 administered and the circulating level of E2, with 25, 50, 100, and 200 micrograms/24 h dosages raising the mean E2 concentrations from mean baseline levels of 5-8 pg/ml to 18, 38, 73, and 100 pg/ml, respectively. Estrone levels also increased with TTS application, but to a lesser extent than did E2 levels. Dose-response reductions of FSH and LH with increasing amounts of E2 administration occurred, but gonadotropin levels were not lowered in any of the patients into the ranges found in premenopausal women. TTS application significantly suppressed the occurrence of HFs at the 50 micrograms/24 h dosage and higher. A significant negative correlation (r = 0.6045; P less than 0.001) between E2 levels and the rates of occurrence of HFs was found during hormone administration. Based on this regression, 50% and 100% reductions of HFs should occur at 61 and 122 pg/ml E2. These data indicate that the transdermal delivery of E2 with these systems significantly reduced the occurrence of HFs and allowed definition of the therapeutic range of hormone replacement in terms of lost ovarian function, as reflected by circulating E2 levels. 相似文献
62.
Bray Emily E. Zheng Zihan Tolbert M. Katherine McCoy Brianah M. Kaeberlein Matt Kerr Kathleen F. 《Age (Dordrecht, Netherlands)》2022,44(3):1779-1790
GeroScience - A variety of diets have been studied for possible anti-aging effects. In particular, studies of intermittent fasting and time-restricted feeding in laboratory rodents have found... 相似文献
63.
Determining the optimal approach to identifying individuals with chronic obstructive pulmonary disease: The DOC study
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![点击此处可从《Journal of evaluation in clinical practice》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Sarah J. Ronaldson MSc BSc Lisa Dyson MSc BA Laura Clark MSc BSc Catherine E. Hewitt PhD MSc BSc David J. Torgerson PhD MSc Brendan G. Cooper PhD MSc BSc Matt Kearney MPH MB ChB William Laughey MBChB MSc Raghu Raghunath PhD MD Lisa Steele BSc Rebecca Rhodes BMED Sci Joy Adamson PhD MSc BSc 《Journal of evaluation in clinical practice》2018,24(3):487-495
64.
Dennis J. Rebergen Sunil B. Nagaraj Eric S. Rosenthal Matt T. Bianchi Michel J. A. M. van Putten M. Brandon Westover 《Journal of clinical monitoring and computing》2018,32(1):53-61
We developed a simple and fully automated method for detecting artifacts in the R-R interval (RRI) time series of the ECG that is tailored to the intensive care unit (ICU) setting. From ECG recordings of 50 adult ICU-subjects we selected 60 epochs with valid R-peak detections and 60 epochs containing artifacts leading to missed or false positive R-peak detections. Next, we calculated the absolute value of the difference between two adjacent RRIs (adRRI), and obtained the empirical probability distributions of adRRI values for valid R-peaks and artifacts. From these, we calculated an optimal threshold for separating adRRI values arising from artifact versus non-artefactual data. We compared the performance of our method with the methods of Berntson and Clifford on the same data. We identified 257,458 R-peak detections, of which 235,644 (91.5%) were true detections and 21,814 (8.5%) arose from artifacts. Our method showed superior performance for detecting artifacts with sensitivity 100%, specificity 99%, precision 99%, positive likelihood ratio of 100 and negative likelihood ratio <0.001 compared to Berntson’s and Clifford’s method with a sensitivity, specificity, precision and positive and negative likelihood ratio of 99%, 78%, 82%, 4.5, 0.013 for Berntson’s method and 55%, 98%, 96%, 27.5, 0.460 for Clifford’s method, respectively. A novel algorithm using a patient-independent threshold derived from the distribution of adRRI values in ICU ECG data identifies artifacts accurately, and outperforms two other methods in common use. Furthermore, the threshold was calculated based on real data from critically ill patients and the algorithm is easy to implement. 相似文献
65.
66.
Jon J. Ford Matt C. Richards Luke D. Surkitt Alexander Y.P. Chan Sarah L. Slater Nicholas F. Taylor Andrew J. Hahne 《Archives of physical medicine and rehabilitation》2018,99(12):2504-2512.e12
Objective
To identify predictors for back pain, leg pain, and activity limitation in patients with early persistent low back disorders (LBDs).Design
Prospective inception cohort study.Setting
Primary care private physiotherapy clinics in Melbourne, Australia.Participants
Individuals (N=300) aged 18-65 years with low back and/or referred leg pain of ≥6 weeks and ≤6 months duration.Interventions
Not applicable.Main Outcome Measures
Numeric rating scales for back pain and leg pain as well as the Oswestry Disability Scale.Results
Prognostic factors included sociodemographics, treatment related factors, subjective/physical examination, subgrouping factors, and standardized questionnaires. Univariate analysis followed by generalized estimating equations were used to develop a multivariate prognostic model for back pain, leg pain, and activity limitation. Fifty-eight prognostic factors progressed to the multivariate stage where 15 showed significant (P<.05) associations with at least 1 of the 3 outcomes. There were 5 indicators of positive outcome (2 types of LBD subgroups, paresthesia below waist, walking as an easing factor, and low transversus abdominis tone) and 10 indicators of negative outcome (both parents born overseas, deep leg symptoms, longer sick leave duration, high multifidus tone, clinically determined inflammation, higher back and leg pain severity, lower lifting capacity, lower work capacity, and higher pain drawing percentage coverage). The preliminary model identifying predictors of LBDs explained up to 37% of the variance in outcome.Conclusions
This study evaluated a comprehensive range of prognostic factors reflective of both the biomedical and psychosocial domains of LBDs. The preliminary multivariate model requires further validation before being considered for clinical use. 相似文献67.
68.
The Tougher the Better: An Economic Analysis of Increased Payment Thresholds on the Performance of General Practices
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We investigate whether and how a change in performance‐related payment motivated General Practitioners (GPs) in Scotland. We evaluate the effect of increases in the performance thresholds required for maximum payment under the Quality and Outcomes Framework in April 2006. A difference‐in‐differences estimator with fixed effects was employed to examine the number of patients treated under clinical indicators whose payment schedules were revised and to compare these with the figures for those indicators whose schedules remained unchanged. The results suggest that the increase in the maximum performance thresholds increased GPs' performance by 1.77% on average. Low‐performing GPs improved significantly more (13.22%) than their high‐performing counterparts (0.24%). Changes to maximum performance thresholds are differentially effective in incentivising GPs and could be used further to raise GPs' performance across all indicators. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
69.
Synthesis of two potent glucocorticoid receptor agonists labeled with carbon‐14 and stable isotopes
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![点击此处可从《Journal of labelled compounds & radiopharmaceuticals》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Bachir Latli Jonathan T. Reeves Zhulin Tan Matt Hrapchak Jinhua J. Song Carl B. Busacca Chris H. Senanayake 《Journal of labelled compounds & radiopharmaceuticals》2015,58(11-12):445-452
Two potent glucocorticoid receptor agonists were prepared labeled with carbon‐14 and with stable isotopes to perform drug metabolism, pharmacokinetics, and bioanalytical studies. Carbon‐14 labeled (1) was obtained from an enantiopure alkyne (5) via a Sonogashira coupling to a previously reported 5‐amino‐4‐iodo‐[2‐14C]pyrimidine [14C]‐(6), followed by a base‐mediated cyclization (1) in 72% overall radiochemical yield. Carbon‐14 labeled (2) was prepared in five steps employing a key benzoic acid intermediate [14C]‐(13), which was synthesized in one pot from enolization of trifluoromethylketone (12), followed by bromine–magnesium exchange and then electrophile trapping reaction with [14C]‐carbon dioxide. A chiral auxiliary (S)‐1‐(4‐methoxyphenyl)ethylamine was then coupled to this acid to give [14C]‐(15). Propargylation and separation of diastereoisomers by crystallizations gave the desired diastereomer [14C]‐(17) in 34% yield. Sonogashira coupling to iodopyridine (10) followed by cyclization to the azaindole [14C]‐(18) and finally removal of the chiral auxiliary gave [14C]‐(2) in 7% overall yield. For stable isotope syntheses, [13C6]‐(1) was obtained in three steps using [13C4]‐(6) and trimethylsilylacetylene‐[13C2] in 26% yield, while [2H5]‐(2) was obtained by first preparing the iodopyridine [2H5]‐(10) in five steps. Then, Sonogashira coupling to chiral alkyne (24) and cyclization gave [2H5]‐(2) in 42% overall yield. 相似文献
70.
Thomas Mason William Whittaker Andrew Jones Matt Sutton 《Addiction (Abingdon, England)》2021,116(11):3082-3093