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排序方式: 共有257条查询结果,搜索用时 46 毫秒
1.
Douglas M. Simon John P. Cello Jorge Valenzuela Richard Levy Gordon Dickerson Richard Goodgame Michael Brown Kip Lyche W.Jeffrey Fessel James Grendell C.Mel Wilcox Nezam Afdhal Ronald Fogel Vonda Reeves-Darby John Stern Owen Smith Frank Graziano Douglas Pleakow Timothy Flanigan Timothy Schubert Mark Loveless Larry Eron Paul Basuk Maurizio Bonacini Jan Orenstein 《Gastroenterology》1995,108(6):1753-1760
Diarrhea is a significant problem in patients with acquired immunodeficiency syndrome (AIDS). The aim of this study was to determine octreotide effectiveness in refractory AIDS-associated diarrhea. In a 3-week protocol, 129 patients with a stool weight of >500 g/day despite standard antidiarrheal therapy were randomized to receive octreotide or placebo (3:2 ratio). Octreotide dose was increased 100 μg weekly to a maximum of 300 μg three times a day based on weekly 72-hour stool collections. Subsequently, patients received open-label octreotide at doses of up to 500 μg three times a day. A 30% decrease in stool weight defined response. After 3 weeks, 48% of octreotide- and 39% of placebo-treated patients had responded (P = 0.43). At 300 μg three times a day, 50% of octreotide- and 30.1% of placebo-treated patients responded (P = 0.12). At a baseline stool weight of 1000–2000 g/day, 57% of octreotide- and 25% of placebo-treated patients responded (P = 0.06). Response rates based on CD4 counts, diarrhea duration, body weight, human immunodeficiency virus risk factor, and presence or absence of pathogens showed no benefit of octreotide. Adverse events were more frequent in the octreotide-treated group. In the doses studied, octreotide was not more effective than placebo in patients with refractory AIDS-associated diarrhea. This lack of effectiveness may be attributable to inadequate sample size, doses, and duration of study treatment. 相似文献
2.
Kensaku Kawamoto Cary J Martin Kip Williams Ming-Chieh Tu Charlton G Park Cheri Hunter Catherine J Staes Bruce E Bray Vikrant G Deshmukh Reid A Holbrook Scott J Morris Matthew B Fedderson Amy Sletta James Turnbull Sean J Mulvihill Gordon L Crabtree David E Entwistle Quinn L McKenna Michael B Strong Robert C Pendleton Vivian S Lee 《J Am Med Inform Assoc》2015,22(1):223-235
Objective To develop expeditiously a pragmatic, modular, and extensible software framework for understanding and improving healthcare value (costs relative to outcomes).Materials and methods In 2012, a multidisciplinary team was assembled by the leadership of the University of Utah Health Sciences Center and charged with rapidly developing a pragmatic and actionable analytics framework for understanding and enhancing healthcare value. Based on an analysis of relevant prior work, a value analytics framework known as Value Driven Outcomes (VDO) was developed using an agile methodology. Evaluation consisted of measurement against project objectives, including implementation timeliness, system performance, completeness, accuracy, extensibility, adoption, satisfaction, and the ability to support value improvement.Results A modular, extensible framework was developed to allocate clinical care costs to individual patient encounters. For example, labor costs in a hospital unit are allocated to patients based on the hours they spent in the unit; actual medication acquisition costs are allocated to patients based on utilization; and radiology costs are allocated based on the minutes required for study performance. Relevant process and outcome measures are also available. A visualization layer facilitates the identification of value improvement opportunities, such as high-volume, high-cost case types with high variability in costs across providers. Initial implementation was completed within 6 months, and all project objectives were fulfilled. The framework has been improved iteratively and is now a foundational tool for delivering high-value care.Conclusions The framework described can be expeditiously implemented to provide a pragmatic, modular, and extensible approach to understanding and improving healthcare value. 相似文献
3.
BACKGROUND & AIMS: We report a novel approach to study biliary water, bile acid, and HCO(3)(-) transport: the microperfusion of intrahepatic bile duct units (IBDUs) isolated from normal rat liver. METHODS: To study water transport, IBDUs were perfused in vitro with a membrane-impermeant fluorescent volume marker, fluorescein sulfonate; net water movement (J(v)) and osmotic water permeability (P(f)) were then calculated. To study solute transport, IBDUs were perfused with taurocholic acid (TCA) and bile acid uptake was calculated from the concentrations of TCA in the perfused and collected solutions. To study ion transport, IBDUs were perfused with the cell-impermeant pH-sensitive dye BCECF dextran; luminal pH was determined from fluorescence excitation ratios. RESULTS: When inward (secretory) or outward (absorptive) osmotic gradients were established across IBDUs, water movement was observed from bath to lumen (i.e., secretion) and from lumen to bath (i.e., absorption). The perfused IBDUs absorbed TCA in a saturable, sodium-dependent manner; in addition, TCA absorption was blocked in a dose-dependent fashion by S0960, a specific inhibitor of the Na(+)/bile acid cotransporter. Addition of forskolin to HCO(3)(-)-containing (but not HCO(3)(-)-free) bath buffer resulted in lumen alkalinization reflecting HCO(3)(-) transport into the lumen of perfused IBDUs. CONCLUSIONS: The results provide direct functional evidence that intrahepatic bile ducts both secrete and absorb water in response to osmotic gradients, actively absorb bile acid, and transport HCO(3)(-). 相似文献
4.
Ryoji Yanai Lama Mulki Eiichi Hasegawa Kimio Takeuchi Harry Sweigard Jun Suzuki Philipp Gaissert Demetrios G. Vavvas Koh-Hei Sonoda Michael Rothe Wolf-Hagen Schunck Joan W. Miller Kip M. Connor 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(26):9603-9608
Ocular neovascularization, including age-related macular degeneration (AMD), is a primary cause of blindness in individuals of industrialized countries. With a projected increase in the prevalence of these blinding neovascular diseases, there is an urgent need for new pharmacological interventions for their treatment or prevention. Increasing evidence has implicated eicosanoid-like metabolites of long-chain polyunsaturated fatty acids (LCPUFAs) in the regulation of neovascular disease. In particular, metabolites generated by the cytochrome P450 (CYP)–epoxygenase pathway have been shown to be potent modulators of angiogenesis, making this pathway a reasonable previously unidentified target for intervention in neovascular ocular disease. Here we show that dietary supplementation with ω-3 LCPUFAs promotes regression of choroidal neovessels in a well-characterized mouse model of neovascular AMD. Leukocyte recruitment and adhesion molecule expression in choroidal neovascular lesions were down-regulated in mice fed ω-3 LCPUFAs. The serum of these mice showed increased levels of anti-inflammatory eicosanoids derived from eicosapentaenoic acid and docosahexaenoic acid. 17,18-epoxyeicosatetraenoic acid and 19,20-epoxydocosapentaenoic acid, the major CYP-generated metabolites of these primary ω-3 LCPUFAs, were identified as key lipid mediators of disease resolution. We conclude that CYP-derived bioactive lipid metabolites from ω-3 LCPUFAs are potent inhibitors of intraocular neovascular disease and show promising therapeutic potential for resolution of neovascular AMD.Angiogenesis plays a central role in many diseases, including age-related macular degeneration (AMD), a leading cause of blindness. Advanced AMD exists in two forms, “atrophic” and “neovascular,” which are defined by the absence or presence of choroidal neovascularization (CNV), respectively (1). Neovascular AMD is characterized by the formation of abnormal blood vessels that grow from the choroidal vasculature, through breaks in Bruch’s membrane, toward the outer retina (1). These vessels generally are immature in nature and leak fluid below or within the retina (2). Although growth factors are thought to play an important role in the late stage of neovascular AMD progression, they likely do not contribute to the underlying cause of the disease. The current standard of care for individuals with neovascular AMD is based on the targeting of VEGF, which promotes both angiogenesis and vascular permeability (3). However, although VEGF-targeted therapy attenuates angiogenesis and vascular permeability, it does not lead to complete vascular regression or disease resolution (3).The ω-3 and ω-6 long-chain polyunsaturated fatty acids (LCPUFAs) are two classes of dietary lipids that are essential fatty acids and have opposing physiological effects. The ω-6 LCPUFA, arachidonic acid (AA), and its cytochrome P450 (CYP)-generated metabolites (epoxyeicosatrienoic acids, EETs) recently have attracted much attention as a result of increasing evidence that they play a role in cancer as well as in cardiovascular disease (4–9). EETs are part of the VEGF-activated signaling cascade leading to angiogenesis (10) and promote tumor growth and metastasis (11). The major dietary ω-3 LCPUFAs are docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), which are highly enriched in the central nervous system including the retina (12). The ω-3 LCPUFAs have antithrombotic, antiangiogenic, and anti-inflammatory properties, and they compete with ω-6 LCPUFAs as substrates for synthesis of downstream metabolites by CYP enzymes, cyclooxygenases (COX), and lipoxygenases (LOX) (6, 13–15). Moreover, dietary enrichment with ω-3 LCPUFAs has been shown to protect against pathological angiogenesis-associated cancer and retinopathy (2, 16–19). Of the three main pathways (COX, LOX, and CYP) involved in eicosanoid biosynthesis, the lipid mediators derived from the CYP branch are the most susceptible to changes in dietary fatty acid composition (20–23). The ω-3 double bond that distinguishes DHA and EPA from their ω-6 counterparts provides a preferred epoxidation site for specific CYP family members (20, 22). In fact, most CYP isoforms can metabolize EPA and DHA with significantly higher catalytic efficiency than AA, making them uniquely susceptible to variations in the availability of these lipids (19–22). CYP epoxygenases target the ω-3 double bond, resulting in an accumulation of 17,18-epoxyeicosatetraenoic acid (17,18-EEQ) derived from EPA and 19,20-epoxydocosapentaenoic acid (19,20-EDP) from DHA (20, 22). Very recently, it was recognized that19,20-EDP inhibits angiogenesis, tumor growth, and metastasis (24). Thus, it appears that the CYP–epoxygenase pathway has the capacity to produce proangiogenic metabolites from ω-6 LCPUFAs (10, 11) and antiangiogenic metabolites from ω-3 LCPUFAs (24). This unique feature of the CYP enzymes may provide a previously unidentified mechanistic link between the ω-6/ω-3 ratio of dietary LCPUFAs and pathological angiogenesis; however, their roles in ocular angiogenesis have been largely unexplored to date.We now show that dietary enrichment with ω-3 LCPUFAs suppresses CNV, vascular leakage, and immune cell recruitment to the lesion site in a mouse model of laser-induced CNV. We characterized the CYP-dependent pathway by which dietary ω-3 LCPUFAs promote resolution of choroidal neovessels in this model and identified CYP-generated metabolites 17,18-EEQ and 19,20-EDP as mediators of disease resolution. Furthermore, we show that expression of adhesion molecules at the CNV site was down-regulated in association with inhibition of leukocyte recruitment in mice receiving ω-3 LCPUFAs. 相似文献
5.
Cooper LT Mather PJ Alexis JD Pauly DF Torre-Amione G Wittstein IS Dec GW Zucker M Narula J Kip K McNamara DM;IMAC Investigators 《Journal of cardiac failure》2012,18(1):28-33
BackgroundWhether myocardial recovery occurs more frequently in peripartum cardiomyopathy (PPCM) than in recent onset cardiomyopathies in men and nonperipartum women has not been prospectively evaluated. This was examined through an analysis of outcomes in the Intervention in Myocarditis and Acute Cardiomyopathy 2 (IMAC2) registry.Methods and ResultsIMAC2 enrolled 373 subjects with recent onset nonischemic dilated cardiomyopathy. Left ventricular ejection fraction (LVEF) was assessed at entry and 6 months, and subjects followed for up to 4 years. Myocardial recovery was compared between men (group 1), nonperipartum women (group 2) and subjects with PPCM (group 3). The cohort included 230 subjects in group 1, 104 in group 2, and 39 in group 3. The mean LVEF at baseline in groups 1, 2, and 3 was 0.23 ± 0.08, 0.24 ± 0.08, and 0.27 ± 0.07 (P = .04), and at 6 months was 0.39 ± 0.12, 0.42 ± 0.11, and 0.45 ± 0.14 (P = .007). Subjects in group 3 had a much greater likelihood of achieving an LVEF >0.50 at 6 months than groups 1 or 2 (19 %, 34%, and 48% respectively, P = .002).ConclusionsProspective evaluation confirms myocardial recovery is greatest in women with PPCM, poorest in men, and intermediate in nonperipartum women. On contemporary therapy, nearly half of women with PPCM normalize cardiac function by 6 months. 相似文献
6.
Ahlke Kip Stefan Priebe Heinz Holling Nexhmedin Morina 《Clinical psychology & psychotherapy》2020,27(4):489-503
Millions of refugees around the globe suffer from posttraumatic stress disorder (PTSD) and/or depression. We conducted a meta‐analysis of randomized controlled trials (RCTs) to determine the efficacy of psychological interventions for PTSD and/or depression in refugees. The meta‐analysis was registered on the PROSPERO database (CRD42017071384). A search using the Medline, PsycINFO, and PILOTS databases was conducted in January 2019, resulting in 17 RCTs, of which 14 were conducted with adult refugees (1,108 participants) and 3 with young refugees (<18 years; 151 participants). Further inclusion criteria were at least 10 participants completing an active psychological intervention for PTSD, depression, or both and less than 50% of participants receiving concurrent psychotropic drugs. Random effects models showed that active interventions for adult PTSD yielded a medium to large aggregated effect size (g = 0.77; 95% confidence interval [CI] [0.26, 1.28]) at posttreatment when compared with passive and active control conditions. Active interventions for adult depression also produced large controlled effect sizes at posttreatment (g = 0.82; 95% CI [0.24, 1.40]). The effects appeared to persist over the average follow‐up period of 6 months. The findings suggest that psychological interventions can effectively reduce symptoms of both PTSD and depression in adult refugees. However, the considerable heterogeneity between studies indicates that the efficacy may vary significantly. Future studies should aim to explore the substantial heterogeneity in effect sizes between studies with adult refugees. Additionally, more trials with young refugees suffering from PTSD or depression are needed to determine treatment efficacy for this population. 相似文献
7.
8.
Kevin C. Stieger James R. Eles Kip A. Ludwig Takashi D. Y. Kozai 《Journal of neuroscience research》2020,98(10):2072-2095
Electrical stimulation has been critical in the development of an understanding of brain function and disease. Despite its widespread use and obvious clinical potential, the mechanisms governing stimulation in the cortex remain largely unexplored in the context of pulse parameters. Modeling studies have suggested that modulation of stimulation pulse waveform may be able to control the probability of neuronal activation to selectively stimulate either cell bodies or passing fibers depending on the leading polarity. Thus, asymmetric waveforms with equal charge per phase (i.e., increasing the leading phase duration and proportionately decreasing the amplitude) may be able to activate a more spatially localized or distributed population of neurons if the leading phase is cathodic or anodic, respectively. Here, we use two-photon and mesoscale calcium imaging of GCaMP6s expressed in excitatory pyramidal neurons of male mice to investigate the role of pulse polarity and waveform asymmetry on the spatiotemporal properties of direct neuronal activation with 10-Hz electrical stimulation. We demonstrate that increasing cathodic asymmetry effectively reduces neuronal activation and results in a more spatially localized subpopulation of activated neurons without sacrificing the density of activated neurons around the electrode. Conversely, increasing anodic asymmetry increases the spatial spread of activation and highly resembles spatiotemporal calcium activity induced by conventional symmetric cathodic stimulation. These results suggest that stimulation polarity and asymmetry can be used to modulate the spatiotemporal dynamics of neuronal activity thus increasing the effective parameter space of electrical stimulation to restore sensation and study circuit dynamics. 相似文献
9.
10.