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排序方式: 共有4104条查询结果,搜索用时 15 毫秒
41.
Agustina Heredia-Martinez Guillermo Rosa-Diez Jorge R. Ferraris Anna-Karin Sohlenius-Sternbeck Carina Nihlen Annika Olsson Jon O. Lundberg Eddie Weitzberg Mattias Carlstrm Rafael T. Krmar 《Nutrients》2022,14(12)
Nitric oxide (NO) contributes to maintaining normal cardiovascular and renal function. This bioactive signalling molecule is generally formed enzymatically by NO synthase in the vascular endothelium. NO bioactivity can also be attributed to dietary intake of inorganic nitrate, which is abundant in our diet, especially in green leafy vegetables and beets. Ingested nitrate is reduced to nitrite by oral commensal bacteria and further to NO systemically. Previous studies have shown that dialysis, by means of removing nitrate and nitrite from the body, can reduce NO bioactivity. Hence, dietary intervention approaches aimed to boost the nitrate–nitrite–NO pathway may be of benefit in dialysis patients. The purpose of this study was to examine the kinetics of plasma nitrate and nitrite after a single intake of nitrate-rich concentrated beetroot juice (BJ) in adult hemodialysis (HD) patients and in age-matched healthy volunteers (HV). Eight HD patients and seven HV participated in this single center, randomized, single-blind, placebo-controlled, crossover study. Each participant received a sequential single administration of active BJ (70 mL, 400 mg nitrate) and placebo BJ (70 mL, 0 mg nitrate) in a random order separated by a washout period of seven days. For the kinetic analysis, blood samples were collected at different time-points before and up to 44 h after BJ intake. Compared with placebo, active BJ significantly increased plasma nitrate and nitrite levels both in HD patients and HV. The area under the curve and the maximal concentration of plasma nitrate, but not of nitrite, were significantly higher in HD patients as compared with HV. In both groups, active BJ ingestion did not affect blood pressure or plasma potassium levels. Both BJs were well tolerated in all participants with no adverse events reported. Our data provide useful information in planning dietary nitrate supplementation efficacy studies in patients with reduced NO bioactivity. 相似文献
42.
Tissue factor produced by the endocrine cells of the islets of Langerhans is associated with a negative outcome of clinical islet transplantation 总被引:15,自引:0,他引:15
Johansson H Lukinius A Moberg L Lundgren T Berne C Foss A Felldin M Källen R Salmela K Tibell A Tufveson G Ekdahl KN Elgue G Korsgren O Nilsson B 《Diabetes》2005,54(6):1755-1762
There are strong indications that only a small fraction of grafts successfully engraft in clinical islet transplantation. One explanation may be the instant blood-mediated inflammatory reaction (IBMIR) elicited by tissue factor, which is produced by the endocrine cells. In the present study, we show that islets intended for islet transplantation produce tissue factor in both the transmembrane and the alternatively spliced form and that the membrane-bound form is released as microparticles often associated with both insulin and glucagon granules. A low-molecular mass factor VIIa (FVIIa) inhibitor that indirectly blocks both forms of tissue factor was shown in vitro to be a promising drug to eliminate the IBMIR. Thrombin-antithrombin complex (TAT) and FVIIa-antithrombin complex (FVIIa-AT) were measured in nine patients who together received 20 infusions of isolated human islets. Both the TAT and FVIIa-AT complexes increased rapidly within 15-60 min after infusion. When the initial TAT and FVIIa-AT levels were plotted against the increase in C-peptide concentration after 7 days, patients with an initially strong IBMIR showed no significant increase in insulin synthesis after 7 days. In conclusion, tissue factor present in both the islets and the culture medium and elicits IBMIR, which affects the function of the transplanted islets. 相似文献
43.
Annika Deckert Christopher A. Waudby Tomasz Wlodarski Anne S. Wentink Xiaolin Wang John P. Kirkpatrick Jack F. S. Paton Carlo Camilloni Predrag Kukic Christopher M. Dobson Michele Vendruscolo Lisa D. Cabrita John Christodoulou 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(18):5012-5017
44.
The influence of steroids on protein synthesis in cervical and uterine tissue obtained from early and term pregnant women was studied by measuring the incorporation of labelled amino acids into total protein. It was found that oestradiol-17 beta and progesterone significantly reduced the incorporation of [3H]proline. Androstenedione and cortisol had no significant effect on the incorporation of [3H]proline even at high concentrations. The protein synthesis inhibitors puromycin and cycloheximide blocked the incorporation of [3H]proline to 80-85%. However, there was no further reduction in the incorporation in the presence of oestradiol. Oestradiol was found to reduce the incorporation of [14C]glycine but not that of [3H]serine. The results indicate that oestradiol and progesterone reduce protein synthesis in human cervical and uterine tissue and that this reduction, at least partially, involves collagen synthesis. Oestradiol and progesterone were equipotent under in vitro experimental conditions. The tissue concentration of progesterone in the pregnant uterus is, however, much higher than that of oestradiol. It seems therefore probable that progesterone rather than oestradiol restricts unopposed synthesis of proteins, presumably mainly collagen. 相似文献
45.
Data management and data analysis techniques in pharmacoepidemiological studies using a pre‐planned multi‐database approach: a systematic literature review 下载免费PDF全文
46.
47.
Andrew J. Vickers Emily A. Vertosick George Lewith Hugh MacPherson Nadine E. Foster Karen J. Sherman Dominik Irnich Claudia M. Witt Klaus Linde 《The journal of pain》2018,19(5):455-474
Despite wide use in clinical practice, acupuncture remains a controversial treatment for chronic pain. Our objective was to update an individual patient data meta-analysis to determine the effect size of acupuncture for 4 chronic pain conditions. We searched MEDLINE and the Cochrane Central Registry of Controlled Trials randomized trials published up until December 31, 2015. We included randomized trials of acupuncture needling versus either sham acupuncture or no acupuncture control for nonspecific musculoskeletal pain, osteoarthritis, chronic headache, or shoulder pain. Trials were only included if allocation concealment was unambiguously determined to be adequate. Raw data were obtained from study authors and entered into an individual patient data meta-analysis. The main outcome measures were pain and function. An additional 13 trials were identified, with data received for a total of 20,827 patients from 39 trials. Acupuncture was superior to sham as well as no acupuncture control for each pain condition (all P?<?.001) with differences between groups close to .5 SDs compared with no acupuncture control and close to .2 SDs compared with sham. We also found clear evidence that the effects of acupuncture persist over time with only a small decrease, approximately 15%, in treatment effect at 1 year. In secondary analyses, we found no obvious association between trial outcome and characteristics of acupuncture treatment, but effect sizes of acupuncture were associated with the type of control group, with smaller effects sizes for sham controlled trials that used a penetrating needle for sham, and for trials that had high intensity of intervention in the control arm. We conclude that acupuncture is effective for the treatment of chronic pain, with treatment effects persisting over time. Although factors in addition to the specific effects of needling at correct acupuncture point locations are important contributors to the treatment effect, decreases in pain after acupuncture cannot be explained solely in terms of placebo effects. Variations in the effect size of acupuncture in different trials are driven predominantly by differences in treatments received by the control group rather than by differences in the characteristics of acupuncture treatment.
Perspective
Acupuncture is effective for the treatment of chronic musculoskeletal, headache, and osteoarthritis pain. Treatment effects of acupuncture persist over time and cannot be explained solely in terms of placebo effects. Referral for a course of acupuncture treatment is a reasonable option for a patient with chronic pain. 相似文献48.
Purpose of Review
This article reviews the recent research and development of electronic health (eHealth) and, in particular, mobile health (mHealth) strategies to deliver behavioral treatment for migraine. Prospects for future development and research of mobile health in migraine are suggested.Recent Findings
Advances in digital technology and mobile technology have led to an era where electronic and mobile approaches are applied to several aspects of healthcare. Electronic behavioral interventions for migraine seem to be acceptable and feasible, but efficacy measures are uncertain. Clinical trials on mHealth-based classical behavioral therapies, such as relaxation, biofeedback, and cognitive behavioral therapy are missing in the literature. Within mHealth, headache diaries are the most researched and scientifically developed. Still, there is a gap between commercially available apps and scientifically validated and developed apps.Summary
Digital technology and mobile health has not yet lived out its potential in behavioral migraine therapy. Application of proper usability and functionality designs towards the right market, together with appraisal of medical and technological recommendations, may facilitate rapid development of eHealth and mHealth, while also establishing scientific evidence.49.
Objectives
To investigate how a virtual cultural simulation experience and guided reflection influenced physiotherapy students’ intrapersonal and interpersonal cultural empathy, and to explore students’ satisfaction with the learning experience.Design
Three research arms within a single cohort: 1) pre-test post-test investigation of intrapersonal cultural empathy; 2) quasi-experimental investigation of interpersonal cultural empathy; 3) post-test measurement of satisfaction.Setting
An Australian university.Participants
Bachelor and Master physiotherapy students, response rate 98% (162/165).Interventions
A self-directed online virtual simulation in which the student assumed the role of a patient who has been hospitalised in a developing country. Students were then guided to reflect on the experience via online questions.Main outcome measures
The primary measure was the Comprehensive State Empathy Scale (CSES) of intrapersonal cultural empathy. Secondary measures were the Theory of Planned Behaviour:Cultural Competence Questionnaire (TPB:CCQ) of interpersonal cultural empathy; and the Satisfaction with Cultural Simulation Experience Scale (SCSES).Results
Intrapersonal cultural empathy improved after the virtual simulation, shown in overall CSES scores [pre-test: 95 (81–109) vs post-test: 106 (89–117); median difference 11; P = <0.001]. For the TPB:CCQ, the post-simulation (‘intervention’) group demonstrated greater ‘Perceived Behavioural Control’ interpersonal empathy compared to the presimulation (‘control’) group [4.41 (0.54) vs 4.59 (0.53); mean difference = 0.19; 95% confidence interval = 0.01 to 0.36; P = 0.020]. Satisfaction with the experience was high (mean SCSES score = 40/56 (71%)).Conclusions
A virtual cultural simulation experience and guided reflection led to significant increases in students’ intrapersonal cultural empathy, with some influence on interpersonal cultural empathy. Students were highly satisfied with this learning experience. 相似文献50.
Yap Sing-Chien Anic Ante Breskovic Toni Haas Annika Bhagwandien Rohit E. Jurisic Zrinka Szili-Torok Tamas Luik Armin 《Journal of interventional cardiac electrophysiology》2022,64(3):565-565
Journal of Interventional Cardiac Electrophysiology - 相似文献