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61.
Grossman D Fernandez L Hopkins K Amastae J Garcia SG Potter JE 《Obstetrics and gynecology》2008,112(3):572-578
OBJECTIVE: To estimate how well a convenience sample of women from the general population could self-screen for contraindications to combined oral contraceptives using a medical checklist. METHODS: Women 18-49 years old (N=1,271) were recruited at two shopping malls and a flea market in El Paso, Texas, and asked first whether they thought birth control pills were medically safe for them. They then used a checklist to determine the presence of level 3 or 4 contraindications to combined oral contraceptives according to the World Health Organization Medical Eligibility Criteria. The women then were interviewed by a blinded nurse practitioner, who also measured blood pressure. RESULTS: The sensitivity of the unaided self-screen to detect true contraindications was 56.2% (95% confidence interval [CI] 51.7-60.6%), and specificity was 57.6% (95% CI 54.0-61.1%). The sensitivity of the checklist to detect true contraindications was 83.2% (95% CI 79.5-86.3%), and specificity was 88.8% (95% CI 86.3-90.9%). Using the checklist, 6.6% (95% CI 5.2-8.0%) of women incorrectly thought they were eligible for use when, in fact, they were contraindicated, largely because of unrecognized hypertension. Seven percent (95% CI 5.4-8.2%) of women incorrectly thought they were contraindicated when they truly were not, primarily because of misclassification of migraine headaches. In regression analysis, younger women, more educated women, and Spanish speakers were significantly more likely to correctly self-screen (P<.05). CONCLUSION: Self-screening for contraindications to oral contraceptives using a medical checklist is relatively accurate. Unaided screening is inaccurate and reflects common misperceptions about the safety of oral contraceptives. Over-the-counter provision of this method likely would be safe, especially for younger women and if independent blood pressure screening were encouraged. 相似文献
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Five strains of virus were recovered from nasal washings and feces. Four strains were of human origin, the fifth strain came from a monkey sacrificed at the height of the disease. Of the four human strains the first was isolated from the feces of a 14 year old child 7 days after the onset of illness. The second strain was from the nasal washings of a 6½ year old child, 5 days after the onset of illness. The third and fourth strains were recovered from the same patient, a 2½ year old child, 9 days after the onset of illness. One of these strains was obtained from nasopharyngeal washings and the other from the feces. The single monkey strain was isolated from the upper intestinal segment and appears to be the only instance of its isolation from this source in the literature. We believe that the detection of the virus in the nasal washings of two additional patients during convalescence lends further support to the belief that the virus of poliomyelitis is spread by human contact. Furthermore, the recovery of the virus from the gastro-intestinal tract with as great or greater frequency as from the upper respiratory tract, need not, it appears to us, alter our concept of the mode of entrance of the virus into the body, namely, by way of the upper respiratory tract. If the presence of the virus is conceded, then a consideration of the physiologic passage of nasal and oral secretions into the gastro-intestinal tract by reflex swallowing would serve to explain adequately the presence of the virus in those organs. It might even be further predicated that since the gastro-intestinal tract functions as a temporary reservoir for secretions from the upper respiratory tract, the gut should, after a time, contain the virus in higher concentration than any single sample of secretion obtained from the upper respiratory tract by nasal washing. It appears to us that failures to detect the virus in the gastro-intestinal tract are perhaps more indicative of inadequate procedures for its detection than of its absence. The recovery of the virus from the feces 7 and 9 days after the onset of illness takes on added significance. It indicates first, that the virus withstands the gastric acidity which under normal physiological conditions tends to keep gastric contents relatively free of bacteria. It further suggests that improper disposal of feces from patients with poliomyelitis may have serious public health consequences, particularly in smaller communities where inadequate sewage disposal may result in contamination of surrounding beaches or even local water systems. 相似文献
65.
Michael Grossman 《Health economics》2016,25(1):3-7
The year 2015 is the 50th anniversary of the publication of ‘A Theory of the Allocation of Time,’ by Gary S. Becker in the 1965 volume of The Economic Journal. To mark that occasion, this editorial focuses on the importance of that paper in the history and evolution of the field of health economics. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
66.
Min Chen Daniel T. Ohm Jeffrey S. Phillips Corey T. McMillan Noah Capp Claire Peterson Emily Xie David A. Wolk John Q. Trojanowski Edward B. Lee James Gee Murray Grossman David J. Irwin 《The Journal of neuroscience》2022,42(18):3868
Network analyses inform complex systems such as human brain connectivity, but this approach is seldom applied to gold-standard histopathology. Here, we use two complimentary computational approaches to model microscopic progression of the main subtypes of tauopathy versus TDP-43 proteinopathy in the human brain. Digital histopathology measures were obtained in up to 13 gray matter (GM) and adjacent white matter (WM) cortical brain regions sampled from 53 tauopathy and 66 TDP-43 proteinopathy autopsy patients. First, we constructed a weighted non-directed graph for each group, where nodes are defined as GM and WM regions sampled and edges in the graph are weighted using the group-level Pearson''s correlation coefficient for each pairwise node comparison. Additionally, we performed mediation analyses to test mediation effects of WM pathology between anterior frontotemporal and posterior parietal GM nodes. We find greater correlation (i.e., edges) between GM and WM node pairs in tauopathies compared with TDP-43 proteinopathies. Moreover, WM pathology strongly correlated with a graph metric of pathology spread (i.e., node-strength) in tauopathies (r = 0.60, p < 0.03) but not in TDP-43 proteinopathies (r = 0.03, p = 0.9). Finally, we found mediation effects for WM pathology on the association between anterior and posterior GM pathology in FTLD-Tau but not in FTLD-TDP. These data suggest distinct tau and TDP-43 proteinopathies may have divergent patterns of cellular propagation in GM and WM. More specifically, axonal spread may be more influential in FTLD-Tau progression. Network analyses of digital histopathological measurements can inform models of disease progression of cellular degeneration in the human brain.SIGNIFICANCE STATEMENT In this study, we uniquely perform two complimentary computational approaches to model and contrast microscopic disease progression between common frontotemporal lobar degeneration (FTLD) proteinopathy subtypes with similar clinical syndromes during life. Our models suggest white matter (WM) pathology influences cortical spread of disease in tauopathies that is less evident in TDP-43 proteinopathies. These data support the hypothesis that there are neuropathologic signatures of cellular degeneration within neurocognitive networks for specific protienopathies. These distinctive patterns of cellular pathology can guide future efforts to develop tissue-sensitive imaging and biological markers with diagnostic and prognostic utility for FTLD. Moreover, our novel computational approach can be used in future work to model various neurodegenerative disorders with mixed proteinopathy within the human brain connectome. 相似文献
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Pressure and volume overload results in concentric and eccentric hypertrophy of cardiac ventricular chambers with, respectively, parallel and series replication of sarcomeres. These divergent patterns of hypertrophy were related 40 years ago to disparate wall stresses in both conditions, with systolic wall stress eliciting parallel replication of sarcomeres and diastolic wall stress, series replication. These observations are relevant to clinical practice, as they relate to the excessive hypertrophy and contractile dysfunction regularly observed in patients with aortic stenosis. Stress-sensing mechanisms in cardiomyocytes and activation of cardiomyocyte death by elevated wall stress continue to intrigue cardiovascular scientists. 相似文献
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Guidelines for the conduct of clinical trials for spinal cord injury as developed by the ICCP panel: clinical trial design 总被引:1,自引:0,他引:1
Lammertse D Tuszynski MH Steeves JD Curt A Fawcett JW Rask C Ditunno JF Fehlings MG Guest JD Ellaway PH Kleitman N Blight AR Dobkin BH Grossman R Katoh H Privat A Kalichman M;International Campaign for Cures of Spinal Cord Injury Paralysis 《Spinal cord》2007,45(3):232-242
The International Campaign for Cures of Spinal Cord Injury Paralysis established a panel tasked with reviewing the methodology for clinical trials for spinal cord injury (SCI), and making recommendations on the conduct of future trials. This is the fourth of four papers. Here, we examine the phases of a clinical trial program, the elements, types, and protocols for valid clinical trial design. The most rigorous and valid SCI clinical trial would be a prospective double-blind randomized control trial utilizing appropriate placebo control subjects. However, in specific situations, it is recognized that other trial procedures may have to be considered. We review the strengths and limitations of the various types of clinical trials with specific reference to SCI. It is imperative that the design and conduct of SCI clinical trials should meet appropriate standards of scientific inquiry to insure that meaningful conclusions about efficacy and safety can be achieved and that the interests of trial subjects are protected. We propose these clinical trials guidelines for use by the SCI clinical research community. 相似文献