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71.
This study examined the criterion validity of self-reported running-related injuries (RRI) by novice runners. Fifty-eight participants (41 females; age 46 ± 11 yrs) of the “Start-to-Run” program provided self-reports on their RRIs using an online questionnaire. Subsequently, they attended injury consultations with sports medicine physicians who provided physician-reports (blinded for the self-reports) as a reference standard. Self-reports and physician-reports included information on injury location (i.e., hip/groin, upper leg, knee, lower leg, and ankle/foot) and injury type (i.e., muscle-tendon unit, joint, ligament, or bone). Sensitivity, specificity, and positive predictive values were 100% for all five injury locations. For injury type, sensitivity was low (66% for muscle-tendon unit, 50% for ligament, and 40% for bone) and lowest for joint injuries (17%). In conclusion, the validity of self-reported RRIs by novice runners is good for injury locations but not for injury types. In particular for joint injuries, the validity of novice runners’ self-reports is low.

Abbreviations: RRI: Running Related Injury; SMC: Sports Medicine Centre; MTU: Muscle Tendon Unit; PPV: Positive Predictive Value  相似文献   

72.

Objectives

To determine the proportion of participants of a running program for novice runners that discontinued running and investigate the main reasons to discontinue and characteristics associated with discontinuation.

Design

Prospective cohort study.

Methods

The study included 774 participants of Start to Run, a 6-week running program for novice runners. Before the start of the program, participants filled-in a baseline questionnaire to collect information on demographics, physical activity and perceived health. The 26-weeks follow-up questionnaire was used to obtain information on the continuation of running (yes/no) and main reasons for discontinuation. To determine predictors for discontinuation of running, multivariable logistic regression was performed.

Results

Within 26 weeks after the start of the 6-week running program, 29.5% of the novice runners (n = 225) had stopped running. The main reason for discontinuation was a running-related injury (n = 108, 48%). Being female (OR 1.74; 95% CI 1.13–2.68), being unsure about the continuation of running after the program (OR 2.06; 95% CI 1.31–3.24) and (almost) no alcohol use (OR 1.62; 95%CI 1.11–2.37) were associated with a higher chance of discontinuation of running. Previous running experience less than one year previously (OR 0.46; 95% CI 0.26–0.83) and a higher score on the RAND-36 subscale physical functioning (OR 0.98; 95% CI 0.96–0.99) were associated with a lower chance of discontinuation.

Conclusions

In this group of novice runners, almost one-third stopped running within six months. A running-related injury was the main reason to stop running. Women with a low perceived physical functioning and without running experience were prone to discontinue running.  相似文献   
73.

Objectives

To investigate the prognosis and possible prognostic factors of running-related injuries (RRIs) in novice runners.

Design

Prospective cohort study.

Methods

Participants of Start to Run, a 6-weeks course for novice runners in The Netherlands, were asked to participate in this study. Before the start of the course a baseline questionnaire, on demographics, physical activity and perceived health, was sent to runners willing to participate. The 26- or 52-weeks follow-up questionnaires assessed information on RRIs and their duration. Only participants that sustained a RRI during follow-up were included in the analyses. An injury duration of 10 weeks or shorter was regarded as a relatively good prognosis, while an injury duration of more than 10 weeks was defined as a poor prognosis. To determine the associations between baseline characteristics and injury prognosis and between injury location and injury prognosis, multivariable logistic regression analyses were performed.

Results

347 participants (48.8%) sustained an RRI during follow-up. The RRIs had an overall median duration of eight weeks (range: 1–52 weeks). Participants with a previous RRI were more likely to have a poor prognosis (OR 2.31; 95%CI 1.12–4.79), while a calf injury showed a trend towards an association with a relatively good prognosis (OR 0.49; 95%CI 0.22–1.11).

Conclusions

The duration of RRIs in novice runners is relatively long, with only calf injuries being associated with a good prognosis. This emphasizes the need of injury prevention measures in novice runners and adequate support during and after an RRI, especially in runners with a previous injury.  相似文献   
74.
Although social support is used to determine transplant eligibility, the relationship between social support, medication adherence, and survival among transplant recipients remains unclear. We estimated the relationship between social support and post-transplant medication adherence and outcomes using 10 electronic databases from inception to January 2016. Study quality was assessed and all review stages were conducted independently by 2 reviewers. Systematic review and meta-analysis were conducted. Thirty-two studies (9102 participants) met inclusion criteria: 21 assessed medication adherence (5197 participants), and 13 assessed clinical outcomes (3905 participants). Among high quality studies, neither social support nor marital status was predictive of medication adherence or post-transplant outcomes. Social support was not associated with medication adherence. It was associated with superior post-transplant outcomes, but the relationship was not significant among high quality studies. Compared to unmarried recipients, married recipients were more likely to adhere to medication post-transplant, but this relationship was not significant among high quality studies. Marital status was not significantly associated with transplant success. Social support is weakly and inconsistently associated with post-transplant adherence and outcomes. Larger prospective studies using consistent and validated measures are needed to justify the use of inadequate social support as a contraindication to transplantation.  相似文献   
75.
There is limited understanding about the frequency of military sexual assault (MSA) in transgender veterans, characteristics associated with MSA, or subsequent mental and behavioral health problems. To address this gap, we used an online national survey of 221 transgender veterans to identify prevalence of MSA and to assess its association with demographic characteristics, past history of sexual victimization, and stigma‐related factors. We also evaluated the association between MSA and several mental and behavioral health problems. Overall, 17.2% of transgender veterans experienced MSA, but rates differed significantly between transgender women (15.2%) and transgender men (30.0%). Using adjusted regression models, MSA was associated with adult sexual assault prior to military service, odds ratio (OR) = 4.05, 95% CI [1.62, 10.08], and distal minority stress during military service, OR = 2.98, 95% CI [1.28, 6.91]. With respect to health outcomes, MSA was associated with past‐month posttraumatic stress disorder (PTSD) symptom severity, B = 10.18, 95% CI [3.45, 16.91]; current depression symptom severity, B = 3.71, 95% CI [1.11, 6.30]; and past‐year drug use, OR = 3.17, 95% CI [1.36, 7.40]. Results highlight the vulnerability of transgender veterans to MSA, and the need for military prevention programs that acknowledge transgender individuals’ heightened risk. Furthermore, clinicians should consider clinical screening for PTSD, depression, and drug use in transgender veterans who have a history of MSA.  相似文献   
76.
Dermal collagen displays a random-like structure that has a major role in strength and function of the human integument. It is hypothesised that collagen bundles align in a parallel fashion in the direction of mechanical tension during scarring, which may explain the problematic scar formation that occurs specifically at joints. Scar tissue and normal skin were biopsied from joints and control areas and evaluated by the Fourier analysis. Collagen orientation was represented by an index ranging from 0 (perfectly random) to 1 (perfectly parallel). Collagen bundle packing signifies the average distance between the centres of collagen bundles. No differences were shown in collagen morphology of scar tissue and normal skin between joints and control areas. Normal skin had a significantly lower collagen orientation index than scar tissue (0.26 versus 0.44, P<0.001). The bundle packing of scar tissue differed significantly from normal skin (18.1 microm versus 23.7 microm, P<0.001). Collagen appeared less parallel orientated in deep dermis compared to superficial dermis especially for normal skin (0.27 versus 0.33, P=0.06). Normal skin had a less parallel organisation in sections that were cut parallel compared to those that were cut perpendicular to the epidermis (0.24 versus 0.30, P=0.02). Collagen orientation of scar tissue is more parallel compared to normal skin. Morphology differs with respect to superficial and deep dermal layers and parallel and perpendicular planes, but appears not to respond to mechanical tension.  相似文献   
77.
In this study, the short component of the 23Na T2 (T2f) and the 23Na and 2H quadrupolar interactions (νQ) were measured in bone‐cartilage samples of osteoarthritic (OA) and osteoporotic (OP) patients. 23Na νQ was found to increase in osteoarthritic articular cartilage relative to controls. Similar results were found in bovine cartilage following proteoglycan (PG) depletion, a condition that prevails in osteoarthritis. 23Na νQ and 1/T2f for articular cartilage obtained from osteoporotic patients were significantly larger than for control and osteoarthritic cartilage. Decalcification of both human and bovine articular cartilage resulted in an increase of 23Na νQ and 1/T2f, showing the same trend as the osteoporotic samples. Differences in the ratio of the intensity of the large 2H splitting to that of the small one in the calcified zone were also observed. In osteoporosis, this ratio was twice as large as that obtained for both control and osteoarthritic samples. The 2H and 23Na results can be interpreted as due to sodium ions and water molecules filling the void created by the calcium depletion and to calcium ions being located in close association with the collagen fibers. To the best of our knowledge, this is the first study reporting differences of NMR parameters in cartilage of osteoporotic patients. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
78.
Following severe injury, not just the skin but also the subcutis may be destroyed. Consequently, the developing scar can become adherent to underlying structures. Reconstruction of the subcutis can be achieved by autologous fat grafting. Our aim was to evaluate the long‐term scar outcome after single‐treatment autologous fat grafting using a comprehensive scar evaluation protocol. Scar assessment was performed preoperatively in 40 patients. A 12‐month follow‐up assessment was performed in 36 patients, using the Cutometer, the Patient and Observer Scar Assessment Scale, and DSM II ColorMeter. The Cutometer parameters elasticity and maximal extension improved with 28 and 22% (both p < 0.001), respectively. Nearly all scores of the scar assessment scale decreased significantly, which corresponds to improved scar quality. In addition, the mean melanin score was ameliorated over time. Thus, we demonstrated the sustainable effectiveness of single‐treatment autologous fat grafting in adherent scars, indicated by improved pliability, and overall scar quality.  相似文献   
79.
In the last two decades, regenerative medicine has shown the potential for “bench‐to‐bedside” translational research in specific clinical settings. Progress made in cell and stem cell biology, material sciences and tissue engineering enabled researchers to develop cutting‐edge technology which has lead to the creation of nonmodular tissue constructs such as skin, bladders, vessels and upper airways. In all cases, autologous cells were seeded on either artificial or natural supporting scaffolds. However, such constructs were implanted without the reconstruction of the vascular supply, and the nutrients and oxygen were supplied by diffusion from adjacent tissues. Engineering of modular organs (namely, organs organized in functioning units referred to as modules and requiring the reconstruction of the vascular supply) is more complex and challenging. Models of functioning hearts and livers have been engineered using “natural tissue” scaffolds and efforts are underway to produce kidneys, pancreata and small intestine. Creation of custom‐made bioengineered organs, where the cellular component is exquisitely autologous and have an internal vascular network, will theoretically overcome the two major hurdles in transplantation, namely the shortage of organs and the toxicity deriving from lifelong immunosuppression. This review describes recent advances in the engineering of several key tissues and organs.  相似文献   
80.
Seventy-seven consecutive postinfarction patients who had either predischarge angina pectoris or congestive heart failure, or who were older than 70 years of age, underwent right atrial (RA) pacing before hospital discharge. In 60% of these patients, ischemic changes developed during RA pacing; this high yield of positive response indicates advanced coronary arterial disease. During a mean follow-up of 15 months, these patients had a high mortality rate (18%) and a reinfarction rate of 9%. RA pacing separated this a priori high-risk group into lower- and higher-risk subsets. Of the 46 patients with a positive RA pacing response, 6 had reinfarction, while none of the 31 patients with a negative RA pacing response had reinfarction (p = 0.04); 10 of the 14 cardiac deaths were among the patients who had positive RA pacing responses at discharge (p = not significant). Thus, of the 20 major cardiac events, 16 occurred among those with positive RA pacing responses (p less than 0.05). Predischarge clinical symptoms, however, were not good predictors of subsequent major cardiac events. We conclude that RA pacing can be safely performed even in high-risk and elderly patients and a positive response can identify those who have a poorer prognosis. Therefore, for postinfarction patients who, according to the prevailing criteria, are excluded from treadmill testing, we advocate the use of RA pacing.  相似文献   
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