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71.
Christina Gjestvang Trine Stensrud Gran Paulsen Lene A. H. Haakstad 《Journal of Sports Science and Medicine》2021,20(1):35
No prospective studies have investigated if repeated testing of physical performance and body composition are associated with exercise attendance or patterns in fitness club members. This study aimed to investigate if repeated physical testing was associated with exercise attendance and patterns in gym members and to report prospective data on use of the fitness club`s facilities and products. Untrained new members were recruited and divided into a test group (n = 125) and as controls (n = 125). All participants answered a survey including exercise involvement, at onset, and after 3, 6, and 12 months follow-up. The test group also measured body composition, maximal oxygen uptake, and maximal muscle strength (onset, and after 3 and 12 months). In total 73.6% answered all surveys, and in the test group, 44.8% completed all physical tests. Regular exercise attendance was defined as ≥2 sessions/week. Repeated testing showed no association with long-term regular exercise attendance (test group: 19.6%, controls: 19.8%; p = 0.638). At 3 months, a lower proportion in the test group reported engagement in resistance exercise (35.3% and 60.2%; p = 0.003) and had lower exercise frequency (2.0 and 2.6 days/week; p = 0.008) than controls. The test group had higher participation in group exercise classes (28.0% and 13.6%; p = 0.040). Exercise frequency decreased from onset to 12 months (from 2.6 to 2.2 days/week; p = 0.025) At 3, 6, and 12 months, 51.8%, 37.6%, and 37.4% reported regular exercise attendance, and 16.9% at all follow-ups. At all time-points, most common workout mode was individual resistance exercise (43.8% to 46.3%). Few attended group exercise classes (7.5% to 13.8%) or used a personal trainer (22.5% to 27.5%). Repeated physical testing did not improve exercise attendance, and we found no changes in members` use of the fitness club`s facilities and products. Only 16.9% reported regular exercise attendance throughout the first year of membership.Key points
- To the authors knowledge this is the first study investigating if repeated physical testing was associated with exercise attendance and patterns in fitness club members.
- The results showed that repeated testing of physical performance and body composition was not associated with exercise attendance.
- With only 17% exercising two days or more per week during the first year of membership, our results indicate that there is a need to develop strategies to improve exercise attendance among new recreational exercisers.
72.
Signe Engkjær Christensen Peter H. Nissen† Peter Vestergaard Lene Heickendorff† Lars Rejnmark Kim Brixen‡ Leif Mosekilde 《Clinical endocrinology》2009,71(6):798-807
Objectives Bone metabolism is only superficially described in familiar hypocalciuric hypercalcaemia (FHH). We describe and compare biochemical and osteodensitometric variables in FHH and primary hyperparathyroidism (PHPT) and assess whether they can improve the diagnostic discrimination between the groups. Design Cross‐sectional. Patients Sixty‐six FHH patients with known calcium‐sensing receptor (CASR) gene mutations and 147 PHPT patients. Measurements We determined calcium, creatinine, phosphate, magnesium, parathyroid hormone (PTH), 25OHD, 1,25(OH)2D and alkaline phosphatase (AP) in plasma, NTx/creatinine ratio in urine and calculated the calcium/creatinine clearance ratio (CCCR). We performed dual energy X‐ray absorptiometry at the lumbar spine, hip, forearm and whole body. Results When compared with normal controls, the FHH patients had increased levels of PTH and AP with normal U‐NTx and regional Z‐scores. Increased phenotypic expression of CASR mutations in terms of hypercalcaemia was associated with higher lumbar spine bone mineral density, but not with bone markers. FHH were younger and leaner than the PHPT patients. They had comparable plasma Ca2+ and 25OHD, but lower levels of PTH, 1,25(OH)2D, AP and U‐NTx. They had higher Z‐scores in the hip and in the forearm. We achieved the best discrimination between groups by multiplying CCCR with AP, 1,25(OH)2D and PTH, but the difference between the area under the curves by receiver operating characteristic analysis remained insignificant. Conclusion Familiar hypocalciuric hypercalcaemia is associated with increased PTH and AP compared to normal controls, but not with bone loss irrespective of the severity of the CASR mutations. A multiplicative model including CCCR, AP, 1,25(OH)2D and PTH insignificantly improved the power of the CCCR to differentiate between FHH and PHPT. However, we still recommend CASR gene analysis in patients with a CCCR <0·020. 相似文献
73.
74.
Using biorelevant dissolution to obtain IVIVC of solid dosage forms containing a poorly-soluble model compound 总被引:1,自引:0,他引:1
Bena-Marie Lue Flemming Seier Nielsen Thomas Magnussen Hanne Mette Schou Kim Kristensen Lene Orup Jacobsen Anette Müllertz 《European journal of pharmaceutics and biopharmaceutics》2008,69(2):648-657
The usefulness of selected biorelevant dissolution media (BDM) to predict in vivo drug absorption was studied. Dissolution profiles of solid formulations of a poorly soluble model compound were compared in BDM simulating fasted and two levels of fed state. A non-physiologically relevant medium containing the cationic surfactant, cetrimide, was also investigated. All the media studied were capable of differentiating between the formulations employed, with formulation A consistently ranking high and formulations C and D ranking low. An in vivo dog study was carried out and an attempt was made to obtain a level A correlation between the plasma absorption curves and in vitro dissolution curves, using non-linear regression software. The in vitro-in vivo correlation (IVIVC) models developed indicated that fed state media (BDM 3) containing high levels of both bile salts (BS) and lipolysis products (LP) were best able to predict in vivo pharmacokinetic parameters (Cmax and AUC) with prediction errors lower than 10%. Overall, design and use of appropriate media for in vitro dissolution is extremely important. This study demonstrates the potential of physiologically relevant media containing both BS and LP for use in formulation and early drug development. 相似文献
75.
76.
Metallothionein I and II (MT-I+II) are antioxidant and tissue protective factors. We have previously shown that MT-I+II prevent oxidative stress and apoptotic cell death and are of therapeutic value in brain inflammation. However, MT-I+II are expressed in glia and it remains to be elucidated if MT-I+II can affect neurons directly. It is likely that MT isoforms could be beneficial also during neurodegenerative disorders. In this study, we have examined if MT-II affects survival and neurite extension of dopaminergic and hippocampal neurons. We show for the first time that MT-II treatment can significantly stimulate neurite extension from both dopaminergic and hippocampal neurons. Moreover, MT-II treatment significantly increases survival of dopaminergic neurons exposed to 6-hydroxydopamine (6-OHDA) and protects significantly hippocampal neurons from amyloid beta-peptide-induced neurotoxicity. Accordingly, treatment with MT-II may be of therapeutic value in neurodegenerative disorders. 相似文献
77.
Schou S Holmstrup P Jørgensen T Skovgaard LT Stoltze K Hjørting-Hansen E Wenzel A 《Clinical oral implants research》2003,14(4):412-422
The aim of the present investigation was to assess the effect of four implant surface preparation methods used in the surgical treatment of experimental peri-implantitis with autogenous bone graft and expanded polytetrafluoroethylene (ePTFE) membrane. The methods were air-powder abrasive unit+citric acid, air-powder abrasive unit, gauze soaked in saline+citric acid, and gauze soaked alternately in chlorhexidine and saline. A total of 64 implants with a titanium plasma-sprayed (TPS) surface was placed in eight cynomolgus monkeys (Macaca fascicularis). After a 3-month period with plaque control, experimental peri-implantitis was induced. A bone loss of 4-6 mm was established after 9-17 months and plaque control was re-implemented. The peri-implantitis defects were surgically exposed, granulation tissue was removed, and each implant surface was prepared by one of the above-mentioned procedures. The defects were then filled with autogenous bone graft particles and covered by an ePTFE membrane. The animals were sacrificed after 6 months. Evaluation by clinical parameters, radiography including quantitative digital subtraction radiography, histology, and stereology did not reveal significant differences between the methods. Almost total bone regeneration and considerable re-osseointegration were obtained irrespective of the method applied. A mean bone-to-implant contact of 39-46% was observed within the defects. Therefore, the present study of implants with a TPS surface in cynomolgus monkeys indicates that the simplest method involving gauze soaked alternately in chlorhexidine and saline should be the preferred implant surface preparation method in the surgical treatment of peri-implantitis involving autogenous bone graft and ePTFE membrane. 相似文献
78.
Svaneborg N Kristensen SD Hansen LM Büllow I Husted SE Schmidt EB 《Thrombosis research》2002,105(4):311-316
Antiplatelet therapy with acetylsalicylic acid (ASA) is commonly used to reduce the risk of cardio- and cerebrovascular events. Fish consumption has been inversely related to coronary disease, which has been partly attributed to an inhibitory effect of n-3 polyunsaturated fatty acids (n-3 PUFA) on platelet production of tromboxane A2. In this study, we investigated the acute and short-time effect of supplementation with n-3 PUFA and intravenous ASA on platelet function, platelet fatty acid composition and plasma lipids. Eighteen healthy men were randomly allocated to a daily intake of 10 g n-3 PUFA or placebo. After this supplement (14 h and 14 days), blood was sampled before and after intravenous injection of 100 mg ASA. n-3 PUFA given for 14 days caused a minor inhibition of platelet reactivity but negligible compared to 100 mg ASA. No additive effect of n-3 PUFA and ASA could be demonstrated. 相似文献
79.
80.
Our knowledge of the regulation of cerebral blood flow (CBF) in ectothermic vertebrates is still very limited. In endothermic vertebrates several peptides have been shown to affect CBF through nitric oxide (NO) dependent mechanisms. Using epi-illumination microscopy in rainbow trout in vivo, we have examined the effects of topically administered oxytocin, arginine vasopressin, substance P and bradykinin on the CBF (measured as erythrocyte velocity in venules on the optic lobes). Of these peptides, only oxytocin induced a dose dependent increase in CBF velocity. Blood pressure remained unchanged and the effect was suppressed by the NOS inhibitor, N(omega)-nitro-L-arginine. This indicates that oxytocin causes NO mediated vasodilation in rainbow trout brain. 相似文献