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991.
OBJECTIVE: To evaluate the relative clinical superiority of increasing the dose of fluticasone propionate versus the addition of salmeterol to low-dose fluticasone propionate for long-term asthma control. DATA SOURCES: Literature was identified by a MEDLINE search (1966-October 2002). Key search terms included asthma, inhalation, corticosteroid, beta-adrenergic agonist, and combination drug therapy. DATA SYNTHESIS: Current guidelines for long-term control of asthma include treatment with either inhaled corticosteroids (medium dose) or inhaled corticosteroids (low to medium dose) in combination with a long-acting bronchodilator. Previous studies evaluating salmeterol or formoterol combination therapy with beclomethasone or budesonide have generally produced superior results compared with increasing the dose of the inhaled corticosteroid. Four recent controlled clinical trials have compared the clinical utility of fluticasone propionate monotherapy versus salmeterol/low-dose fluticasone propionate for long-term asthma control in patients with moderate to severe persistent asthma. Based on spirometry data, rescue albuterol use, and symptom scores, the addition of salmeterol to low-dose fluticasone propionate was superior to increasing the dose of fluticasone propionate. CONCLUSIONS: Based on improvements in forced expiratory volume in 1 second, peak expiratory flow, and symptom control, the addition of salmeterol to low-dose fluticasone propionate provides better control of asthma than increasing the dose of fluticasone propionate. 相似文献
992.
993.
Morris R. Dixon Chair ; Nancy Eckert Thomas Hathaway Mary Lieb Kim Sanchez Jean Stanley Philip Schiff Development Work Group ; Aaron Liberman Timothy Rotarius Facilitators 《Transfusion》2005,45(S4):241S-247S
This special edition of TRANSFUSION is dedicated to those colleagues in the transfusion medicine and cellular therapy field who have wondered about what the future holds for their chosen professions. Each of the six peer-reviewed Think Tank articles included in this special edition focuses on an administrative issue that is critical to the survivability and enhancement of the industry. Each issue is examined from two perspectives: Where are we now? And where are we heading? 相似文献
994.
Nikolaidis LA Trumble D Hentosz T Doverspike A Huerbin R Mathier MA Shen YT Shannon RP 《European journal of heart failure》2004,6(4):409-419
To investigate the metabolic cost of catecholamine use in heart failure, we administered intravenous dobutamine or norepinephrine to dogs with moderate and severe LV dysfunction until LV contractile function was restored to normal levels. Both drugs were associated with significant increases in myocardial O(2) consumption, increased coronary blood flow requirements and decreased myocardial mechanical efficiency. These mechanisms may contribute to the deleterious effects of catecholamines in heart failure. 相似文献
995.
Rachdi L Balcazar N Osorio-Duque F Elghazi L Weiss A Gould A Chang-Chen KJ Gambello MJ Bernal-Mizrachi E 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(27):9250-9255
Regulation of pancreatic beta cell mass and function is a major determinant for the development of diabetes. Growth factors and nutrients are important regulators of beta cell mass and function. The signaling pathways by which these growth signals modulate these processes have not been completely elucidated. Tsc2 is an attractive candidate to modulate these processes, because it is a converging point for growth factor and nutrient signals. In these experiments, we generated mice with conditional deletion of Tsc2 in beta cells (betaTsc2(-/-)). These mice exhibited decreased glucose levels and hyperinsulinemia in the fasting and fed state. Improved glucose tolerance in these mice was observed as early as 4 weeks of age and was still present in 52-week-old mice. Deletion of Tsc2 in beta cells induced expansion of beta cell mass by increased proliferation and cell size. Rapamycin treatment reversed the metabolic changes in betaTsc2(-/-) mice by induction of insulin resistance and reduction of beta cell mass. The reduction of beta cell mass in betaTsc2(-/-) mice by inhibition of the mTOR/Raptor (TORC1) complex with rapamycin treatment suggests that TORC1 mediates proliferative and growth signals induced by deletion of Tsc2 in beta cells. These studies uncover a critical role for the Tsc2/mTOR pathway in regulation of beta cell mass and carbohydrate metabolism in vivo. 相似文献
996.
Growth differentiation factor-9 induces Smad2 activation and inhibin B production in cultured human granulosa-luteal cells 总被引:16,自引:0,他引:16
Kaivo-Oja N Bondestam J Kämäräinen M Koskimies J Vitt U Cranfield M Vuojolainen K Kallio JP Olkkonen VM Hayashi M Moustakas A Groome NP ten Dijke P Hsueh AJ Ritvos O 《The Journal of clinical endocrinology and metabolism》2003,88(2):755-762
The TGF beta family member growth differentiation factor-9 (GDF-9) is an oocyte-derived factor that is essential for mammalian ovarian folliculogenesis. GDF-9 mRNAs have been shown to be expressed in the human ovarian follicle from the primary follicle stage onward, and recombinant GDF-9 has been shown to promote human ovarian follicle growth in vitro. In this study with primary cultures of human granulosa-luteal (hGL) cells, we investigated whether recombinant GDF-9 activates components of the Smad signaling pathways known to be differentially activated by TGF beta and the bone morphogenetic proteins (BMPs). As with TGF beta, GDF-9 treatment caused the phosphorylation of endogenous 53-kDa proteins detected in Western blots with antiphospho-Smad2 antibodies (alpha PS2). However, unlike BMP-2, GDF-9 did not activate the phosphorylation of antiphospho-Smad1 antibody (alphaPS1)-immunoreactive proteins in hGL cells. Infection of hGL cells with an adenovirus expressing Smad2 (Ad-Smad2) confirmed that GDF-9 activates specifically phosphorylation of the Smad2 protein. Infection of hGL cells with Ad-Smad7, which expresses the inhibitory Smad7 protein, suppressed the levels of both GDF-9-induced endogenous and adenoviral alpha PS2-reactive proteins. Furthermore, GDF-9 increased the steady state levels of inhibin beta(B)-subunit mRNAs in hGL cells and strongly stimulated the secretion of dimeric inhibin B. Again, Ad-Smad7 blocked GDF-9-stimulated inhibin B production in a concentration-dependent manner. We identify here for the first time distinct molecular components of the GDF-9 signaling pathway in the human ovary. Our data suggest that GDF-9 mediates its effect through the pathway commonly activated by TGF beta and activin, but not that activated by many BMPs. The results are also consistent with the suggestion that in addition to endocrine control of inhibin production by gonadotropins, a local paracrine control of inhibin production is likely to occur via oocyte-derived factors in the human ovary. 相似文献
997.
998.
999.
Jonathan T. Unkart Matthew A. Allison Michael H. Criqui Mary M. McDermott Alexis C. Wood Aaron R. Folsom Donald Lloyd-Jones Laura J. Rasmussen-Torvik Norrina Allen Gregory Burke Moyses Szklo Mary Cushman Robyn L. McClelland Christina L. Wassel 《American journal of preventive medicine》2019,56(2):262-270
1000.
Hanadi Hamadi Emma Apatu Chung‐Ping Albert Loh Hyett Farah Kirk Walker Aaron Spaulding 《The International journal of health planning and management》2019,34(1):e354-e368
The shift from a fee‐for‐service payment to a value‐based payment scheme, sparked by the Patient Protection and Affordable Care Act, introduced pay‐for‐performance programs such Hospital Value Based Purchasing. Previous inquiry has not considered how local community factors may affect hospital system performance. This study investigated the association between local health performance and minority population in a hospital referral region (HRR). The primary objective was to ascertain whether community diversity levels are significantly associated to local health performance guided by the ecological model. Secondary data analysis collected from the 2016 American Hospital Association, Area Health Resource File, Commonwealth Fund Scorecard on Local Health System Performance, and the Dartmouth Atlas HRR dataset was used. Our primary findings show that the more diverse a HRR is, the more likely it is to be associated with lower ranking for access and affordability prevention and treatment avoidable hospital use and cost as well as healthy lives. Total performance score was significantly related to a better health ranking on prevention and treatment, hospital use, and cost, as well as healthy lives. This research supports the assertion that communities, particularly minorities in those communities, affect local health care performance in a variety of ways. 相似文献