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61.
Paul D Howard Andrea N Dolan Anthony N Falco Brett M Holland Caitlin F Wilkinson Anna M Zink 《Journal of Manual and Manipulative Therapy》2013,21(4):213-221
AbstractThe purpose of this study was to test the hypothesis that positional distraction provides immediate relief of unilateral leg pain suspected to be caused by lumbar-nerve root irritation. Thirty subjects with true neurological signs were randomly assigned to a treatment group or control group. The treatment group received positional distraction for five minutes and the control group lay in side-lying for the same amount of time. Pain intensity, pain location, and SLR test height data was taken pre- and post-test. Statistical analysis was completed with the Wilcoxin-signed rank test for the data of pain intensity and with the paired sample t-test for the SLR height. The treatment group was found to have significantly less pain, more centralization of pain, and an increase in SLR test height (p-values of 0.001, 0.006, and 0.005 respectively). The control group showed no significant change (p-values of 0.506, 0.480, 0.884). 相似文献
62.
Brett A. Colson Inna N. Rybakova Ewa Prochniewicz Richard L. Moss David D. Thomas 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(50):20437-20442
We have determined the effects of myosin binding protein-C (MyBP-C) and its domains on the microsecond rotational dynamics of actin, detected by time-resolved phosphorescence anisotropy (TPA). MyBP-C is a multidomain modulator of striated muscle contraction, interacting with myosin, titin, and possibly actin. Cardiac and slow skeletal MyBP-C are known substrates for protein kinase-A (PKA), and phosphorylation of the cardiac isoform alters contractile properties and myofilament structure. To determine the effects of MyBP-C on actin structural dynamics, we labeled actin at C374 with a phosphorescent dye and performed TPA experiments. The interaction of all three MyBP-C isoforms with actin increased the final anisotropy of the TPA decay, indicating restriction of the amplitude of actin torsional flexibility by 15–20° at saturation of the TPA effect. PKA phosphorylation of slow skeletal and cardiac MyBP-C relieved the restriction of torsional amplitude but also decreased the rate of torsional motion. In the case of fast skeletal MyBP-C, its effect on actin dynamics was unchanged by phosphorylation. The isolated C-terminal half of cardiac MyBP-C (C5–C10) had effects similar to those of the full-length protein, and it bound actin more tightly than the N-terminal half (C0–C4), which had smaller effects on actin dynamics that were independent of PKA phosphorylation. We propose that these MyBP-C-induced changes in actin dynamics play a role in the functional effects of MyBP-C on the actin–myosin interaction. 相似文献
63.
Daniel R. Burnett Lauren M. Huyett Howard C. Zisser Francis J. Doyle III Brett D. Mensh 《Diabetes》2014,63(7):2498-2505
The paramount goal in the treatment of type 1 diabetes is the maintenance of normoglycemia. Continuous glucose monitoring (CGM) technologies enable frequent sensing of glucose to inform exogenous insulin delivery timing and dosages. The most commonly available CGMs are limited by the physiology of the subcutaneous space in which they reside. The very same advantages of this minimally invasive approach are disadvantages with respect to speed. Because subcutaneous blood flow is sensitive to local fluctuations (e.g., temperature, mechanical pressure), subcutaneous sensing can be slow and variable. We propose the use of a more central, physiologically stable body space for CGM: the intraperitoneal space. We compared the temporal response characteristics of simultaneously placed subcutaneous and intraperitoneal sensors during intravenous glucose tolerance tests in eight swine. Using compartmental modeling based on simultaneous intravenous sensing, blood draws, and intraarterial sensing, we found that intraperitoneal kinetics were more than twice as fast as subcutaneous kinetics (mean time constant of 5.6 min for intraperitoneal vs. 12.4 min for subcutaneous). Combined with the known faster kinetics of intraperitoneal insulin delivery over subcutaneous delivery, our findings suggest that artificial pancreas technologies may be optimized by sensing glucose and delivering insulin in the intraperitoneal space. 相似文献
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Daniel G. Morris Brett F. Truitt Angela Kong Norma Leyva 《Pharmaceutical development and technology》2013,18(5):451-460
The purpose of this study was to investigate the impact of processing, API loading, and formulation composition on the content uniformity of low-dose tablets made using direct compression (DC) and roller compaction (RC) methods at 1?kg scale. Blends of 1:1 microcrystalline cellulose/lactose or 1:1 microcrystalline cellulose/dicalcium phosphate anhydrous with active pharmaceutical ingredient (API) at loadings of 0.2, 1 and 5% were processed either by DC or RC. A statistical analysis showed that DC produced comparable content uniformity results to RC. Microcrystalline cellulose/lactose formulations had improved average potency compared to microcrystalline cellulose/dicalcium phosphate anhydrous formulations for both DC and RC. The impact of segregation in the DC blends and adhesion to equipment surfaces was assessed to aid in understanding potency trends. DC may be as suitable as RC for low-dose regime (e.g. <?1?mg) when manufacturing clinical supplies at small scale provided the API has a suitable particle size and potency loss to equipment is negligible. 相似文献
68.
Jason M. Mehal Robert C. Holman Danny A. Brass Jesse D. Blanton Brett W. Petersen 《The American journal of tropical medicine and hygiene》2014,90(2):263-264
The purpose of the study was to evaluate changes in the knowledge of bat rabies and human exposure among United States cavers during the last decade. A survey was distributed among cavers who attended the National Speleological Society convention in 2000 and those who attended in 2010. In 2000 and 2010, 392 and 108 cavers, respectively, responded to the questionnaire. Eighty-five per cent of respondents in 2000 indicated a bat bite as a risk for rabies compared with all respondents in 2010 (P < 0.0001 controlling for age). The proportion of respondents indicating that they were advised to receive rabies pre-exposure prophylaxis (PreEP) because of caving increased (17% and 29%; P = 0.03 controlling for age). Among these, PreEP was received by 56% and 45%. Although recognition of the risk of rabies exposure from bats is important, the proportion of cavers acting on current recommendations regarding PreEP does not appear to have improved in the past decade. 相似文献
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70.
Brett Schrewe Daniel D. Pratt William H. McKellin 《Advances in health sciences education : theory and practice》2016,21(2):475-499
Emergent discourses of social responsibility and accountability have in part fuelled the expansion of distributed medical education (DME). In addition to its potential for redressing physician maldistribution, DME has conferred multiple unexpected educational benefits. In several countries, its recent rise has occurred around the boundaries of traditional medical education practices. Canada has been no exception, with DME proliferating against a backdrop of its longstanding central node, the clinical teaching unit (CTU). The CTU first appeared just over 50 years ago with its position in Canadian health care largely taken-for-granted. Given the increasing prominence of DME, however, it is timely to reconsider what the place of tertiary centre-based practices such as the CTU might be in shifting medical education systems. From a genealogical perspective, it becomes clear that the CTU did not just “happen”. Rather, its creation was made possible by multiple interrelated cultural, social, and political changes in Canadian society that, while subtle, are powerfully influential. Making them visible offers a better opportunity to harmonize the benefits of longstanding entities such as the CTU with novel practices such as DME. In so doing, the medical education field may sidestep the pitfalls of investing significant resources that may only produce superficial changes while unwittingly obstructing deeper transformations and improvements. Although this work is refracted through a Canadian prism, reconceptualizing the overall design of medical education systems to take advantage of both tradition and innovation is a persistent challenge across the international spectrum, resistant to tests of time and constraints of context. 相似文献