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排序方式: 共有9659条查询结果,搜索用时 15 毫秒
61.
Aaron Persinger Matthew Butawan Martina Faietti Ashley Pryke Kyley Rose Marie van der Merwe Richard J. Bloomer Melissa J. Puppa 《Nutrients》2021,13(5)
Time-restricted feeding (TRF) is becoming a popular way of eating in physically active populations, despite a lack of research on metabolic and performance outcomes as they relate to the timing of food consumption in relation to the time of exercise. The purpose of this study was to determine if the timing of feeding/fasting after exercise training differently affects muscle metabolic flexibility and response to an acute bout of exercise. Male C57BL/6 mice were randomized to one of three groups for 8 weeks. The control had ad libitum access to food before and after exercise training. TRF-immediate had immediate access to food for 6 h following exercise training and the TRF-delayed group had access to food 5-h post exercise for 6 h. The timing of fasting did not impact performance in a run to fatigue despite TRF groups having lower hindlimb muscle mass. TRF-delayed had lower levels of muscle HSL mRNA expression and lower levels of PGC-1α expression but displayed no changes in electron transport chain enzymes. These results suggest that in young populations consuming a healthy diet and exercising, the timing of fasting may not substantially impact metabolic flexibility and running performance. 相似文献
62.
Lindsay H. Dewa Caroline Crandell Elizabeth Choong Jack Jaques Alex Bottle Catherine Kilkenny Anna Lawrence-Jones Martina Di Simplicio Dasha Nicholls Paul Aylin 《The Journal of adolescent health》2021,68(4):666-675
PurposeExploring the impact of the COVID-19 pandemic on young people’s mental health is an increasing priority. Studies to date are largely surveys and lack meaningful involvement from service users in their design, planning, and delivery. The study aimed to examine the mental health status and coping strategies of young people during the first UK COVID-19 lockdown using coproduction methodology.MethodsThe mental health status of young people (aged 16–24) in April 2020 was established utilizing a sequential explanatory coproduced mixed methods design. Factors associated with poor mental health status, including coping strategies, were also examined using an online survey and semi-structured interviews.ResultsSince the lockdown, 30.3% had poor mental health, and 10.8% had self-harmed. Young people identifying as Black/Black-British ethnicity had the highest increased odds of experiencing poor mental health (odds ratio [OR] 3.688, 95% CI .54–25.40). Behavioral disengagement (OR 1.462, 95% CI 1.22–1.76), self-blame (OR 1.307 95% CI 1.10–1.55), and substance use (OR 1.211 95% CI 1.02–1.44) coping strategies, negative affect (OR 1.109, 95% CI 1.07–1.15), sleep problems (OR .915 95% CI .88–.95) and conscientiousness personality trait (OR .819 95% CI .69–.98) were significantly associated with poor mental health. Three qualitative themes were identified: (1) pre-existing/developed helpful coping strategies employed, (2) mental health difficulties worsened, and (3) mental health and nonmental health support needed during and after lockdown.ConclusionPoor mental health is associated with dysfunctional coping strategies. Innovative coping strategies can help other young people cope during and after lockdowns, with digital and school promotion and application. 相似文献
63.
64.
Di Rienzo Alessandro Colasanti Roberto Gladi Maurizio Dobran Mauro Della Costanza Martina Capece Mara Veccia Salvatore Iacoangeli Maurizio 《Neurosurgical review》2021,44(3):1523-1532
Neurosurgical Review - The optimal management of cranioplasty infections remains a matter of debate. Most authors have suggested that the infected bone/implant removal is mandatory, combined with... 相似文献
65.
Julia M. Grottenthaler Annette Konzelmann Anette Stiegler Clemens Hinterleitner Sarah M. Bott Thomas Klag Christoph R. Werner Martina Hinterleitner Alfred Königsrainer Anil Batra Nisar P. Malek Silvio Nadalin Christoph P. Berg 《Transplant international》2021,34(11):2257-2265
Alcohol abuse after liver transplantation can seriously impact graft and patient survival. However, to date, there is no defined standard procedure to identify patients consuming alcohol after liver transplantation. The aim of this study was to analyze the diagnostic value and clinical impact of routinely measured urinary ethyl glucuronide (uEtG) – a metabolite of ethanol – in patients after liver transplantation. Data of 362 consecutive patients after liver transplantation who visited the University Hospital of Tuebingen for outpatient follow-up were analyzed. Forty-eight patients (13%) displayed positive uEtG results. The uEtG positive group contained significantly more patients with pretransplant alcoholic liver disease. However, two thirds of the uEtG positive patients had no history of pretransplant alcoholic liver disease. Several clinical parameters were significantly associated with positive uEtG. In order to enable a more cost-effective application of uEtG in the future, a clinical risk score was developed (specificity 0.95). In conclusion, routine testing for uEtG reveals a considerable percentage of patients practicing alcohol intake after liver transplantation. Application of our proposed risk score could help focusing uEtG testing on patients at risk. 相似文献
66.
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68.
Thomas Wieland Klaus Liedel Sylvia Kaldenberg-Stasch Dagmar Meyer zu Heringdorf Martina Schmidt Karl H. Jakobs 《Naunyn-Schmiedeberg's archives of pharmacology》1995,351(4):329-336
Receptor-induced binding of the stable GTP analogue, guanosine 5-[-thio]triphosphate (GTP [S]), to guanine nucleotide-binding regulatory proteins (G proteins) was measured in various permeabilized cells. In myeloid differentiated human leukemia (HL-60) cells, permeabilized with either digitonin, streptolysin O or Staphylococcus aureus -toxin, binding of GTP [S] induced by three distinct chemoattractant receptors was observed. The extent of receptor-stimulated GTP [S] binding (maximally about 2-fold) was independent of the type of permeabilizing agent used. In human erythroleukemia cells permeabilized with digitonin, agonist activation of thrombin and neuropeptide Y receptors increased GTP [S] binding by 1.8- and 1.5-fold, respectively. Finally, in adherently grown human embryonic kidney cells permeabilized with digitonin, activation of the stably expressed human muscarinic m3 receptor increased GTP[S] binding by about 1.6-fold. In digitonin-permeabilized HL-60 cells, a quantitative analysis of formyl peptide receptors and interacting G proteins was performed. About 50,000 formyl peptide receptors per cell were detected. Agonist binding to these receptors was fully sensitive to regulation by guanine nucleotides and pertussis toxin. The number of high-affinity GTP [S] binding sites, most likely representing heterotrimeric G proteins, was calculated to be about 670,000 per cell. Stimulation of formyl peptide receptors led to the activation of about 130,000 of high-affinity GTP [S] binding sites, indicating a ratio of about three activated G proteins per one agonist-activated receptor.Overall, this study indicates that receptor-stimulated GTP [S] binding to G proteins in permeabilized cells is a sensitive and rapid method for analyzing receptor-G protein interactions, which can be applied to a variety of cultured cells and for various receptor systems. 相似文献
69.
Purpose. The effects of 2-hydroxypropyl--cyclodextrin (HP--CD) on the aqueous solubility and stability of two lipophilic bispilocarpine prodrugs were investigated at pH 7.4.
Methods. The solubility of prodrugs was studied by phase-solubility method (0–72.5 mM HP--CD). The stability of one of the prodrugs was investigated as a function of temperature (40°C–70°C) and HP--CD concentration (0–72.5 mM). The apparent rate constants (k
1, k
2) for degradation of prodrug in 1:1 and 1:2 inclusion complexes and apparent stability constants (K
1:1, K
l:2) were calculated by the curve-fitting method.
Results. The phase-solubility diagrams were classified as Ap-type and the apparent stability constants (K
l:l, K
l:2) for 1:1- and 1:2-inclusion complexes were calculated to be 143–815 M–l and 29–825 M–1, respectively. The stability of prodrug increased as a function of HP--CD concentration over the studied temperature range. The shelf-life (t
90%, calculated by the Arrhenius equation) of the prodrug in 72.5 mM HP--CD solution increased 5.1-fold and 6.1-fold at 25°C and 4°C, respectively.
Conclusions. The solubility of the prodrugs was shown to increase markedly in phase-solubility studies. The degradation rate of prodrug in stability studies was shown to be slower in the l:2-complex than in the l:l-complex and the relative amounts of complex species were found to be dependent on CD concentration. 相似文献
70.
Robert M. Mader Harald Zilg Otto Schlappack Günther G. Steger Martina Baur Bertold Greifenberg Uwe Heberle Christian Dittrich 《Cancer chemotherapy and pharmacology》1995,37(1-2):91-96
Improved quality of life has gained importance over shortly lasting remissions in yet incurable metastatic breast cancer. Fractionation of drug administration is one of the possible approaches to reduce the concentration-dependent toxicity of anthracyclines. We evaluated the pharmacokinetics of 4-O-tetrahydropyranyladriamycin (THP-ADM) under weekly administration in patients with advanced breast cancer (dose escalation, from 20 to 27 mg/m2 THP-ADM). The concentration-time curves of THP-ADM in plasma were best described by an open three-compartment model [half-life of the first disposition phase (t1/2), 3.15 min; terminal elimination half-life (t
1/2), 13.9 h] with a mean area under the curve (AUC) of 12.2 ng h ml–1mg–1m–2, resulting in a mean plasma clearance of 86.91 h–1m–2. Metabolism included the formation of Adriamycin (ADM), Adriamycinol (ADM-OH), 13-dihydro-4-O-tetrahydropyranyladriamycin (THP-OH), 7-deoxyadriamycinone (7H-ADn), and 7-deoxy-13-dihydroadrimycinone (7H-ADn-OH), with maximal plasma concentrations ranging from 2.8 to 5.5 ng/ml. The mean total amount of cytotoxic anthracyclines excreted into urine, mainly as the parent drug, was 5% of the delivered dose. ADM and ADM-OH, but not the parent drug, were observed in urine at up to 4 weeks after the last therapeutic cycle. There was a significant correlation between the leukocyte nadir under therapy and the AUC of ADM-OH (r=0.800,P<0.05). Since no shift in the plasma kinetics was observed from the first to the sixth cycle, the favorable ratio of the AUCs of THP-ADM and ADM after fractionation of THP-ADM suggests lower toxic side effects attributable to ADM. This hypothesis was confirmed in a clinical study, where no severe cardiotoxicity and only mild alopecia were observed in 19 patients. Thus, pharmacokinetics studies might be helpful in both individualization of therapy with THP-ADM and optimization of the administration schedule. 相似文献