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Ultra-triathlons are defined as triathlons longer than the traditional Ironman distance and became more popular in the last two decades; however, scarce scientific evidence of these events are available. Therefore, we aimed to investigate the trends of performance, pacing, nationality, sex differences, and rate of non-finishers in ultra-triathlons. Data from 1985 to 2018 were collected including Double Iron, Triple Iron, Quintuple Iron, and Deca Iron ultra-triathlons. Different pacing patterns by event and sex were observed (P < .05); athletes spent less %time in swimming and cycling, and more %time in running as the distance of event was longer; women spent more %time in cycling and less% time in running in Double and Triple. Performance analysis showed a negative trend over time for men and women since 1985. Switzerland, France, and Germany were the fastest nations in ultra-triathlons. The frequency of North Americans competing in Europe was very low (<5%), whereas Europeans often competed in North America (~25%). The rate of non-finishers between sexes was similar in all races with the exception of Deca Iron ultra-triathlon, which was much greater (~20%) for women. Non-finishers had slower race times in swimming and cycling splits than finishers. In conclusion, ultra-triathletes should redistribute their energy among swimming, cycling, and running depending on their sex and distance of race. Performance in ultra-triathlons has been decreasing in men and women over the years, but sex difference in performance remained. Europeans were the fastest ultra-triathletes and compete in Europe and North America. Additionally, non-finishers were slower swimmers and cyclists than finishers.  相似文献   

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The overhead throwing motion generates enormous force in the elbow. Repetitive near failure loads lead to chronic adaptive changes and occasionally acute injury. The physician caring for the thrower must understand the complex anatomy and function of the elbow joint, along with the biomechanics of throwing, to accurately diagnose and treat elbow pathology. Evaluation of elbow pain in the throwing athlete must begin with a thorough and detailed throwing history including duration of symptoms, location of pain, timing during the phases of throwing motion, and associated symptoms. Physical examination should include inspection, range of motion, palpation, and specific tests to better define the pathology. A detailed history and physical examination will allow the astute clinician to obtain the proper diagnosis and start the appropriate operative or nonoperative treatment often without reliance on ancillary testing. Treatment and rehabilitation of these injuries must be tailored to the pathology present and focused towards a return to the athlete’s activity.  相似文献   

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Cellulose triacetate (CTA) films are useful dosimeters for radiation processing with γ rays and electron beams, and are usually analyzed by u.v. spectrophotometry. The radiation sensitivity of CTA film material increases linearly with both temperature (around room temperature) and relative humidity (between 20 and 80% r.h.) when irradiated at lower dose rates typical for 60Co γ-ray irradiation (< 100 kGy h−1). On the other hand, the response depends neither on temperature up to 45°C nor on relative humidity of the surrounding atmosphere during irradiation at high dose rates above 1 MGy h−1, which are typical for electron irradiation. In fact, the extent of temperature dependence and humidity of response are markedly influenced by dose rate. There are also appreciable influences of temperature and relative humidity changes during the post-irradiation storage, but in this case there is no difference of storage effect for different dose levels. The thickness of CTA film influences the dose-rate dependence in the range between 10 kGy h−1 and 1 MGy h−1, but not the dependence on temperature during irradiation. Other environmental influences on the sensitivity were also examined, for the purpose of evaluating systematic uncertainties due to these effects in practical dosimetry.  相似文献   

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"People or places: what should be the target?" was the provocative title of a keynote session at the fifth Australian National Physical Activity Conference held in Melbourne in 2005. This paper will argue that in fact there need not be major conflict between these views, and that couching recent debate about physical activity promotion as a polarised choice between these presents a false dichotomy. To illustrate this, the paper will consider several problems with singular approaches to understanding and promoting physical activity, and will then describe emerging empirical evidence on the nexus between people and places. To balance an increasing emphasis in the scientific literature on physical environmental determinants of physical activity, the role of intrapersonal and social factors will also be revisited. It is concluded that growing evidence supporting the multiple domains of influence on physical activity justifies calls for multi-disciplinary and multi-sectoral partnerships and approaches to the promotion of active lifestyles.  相似文献   

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Purpose

There is increasing emphasis on publication quality and internationalization of author groups in orthopaedic literature. The purpose of this review was to evaluate the type of studies and the level of evidence (LOE) published in knee surgery, sports traumatology, arthroscopy (KSSTA) from 1995 to 2015. The secondary aim was to analyze trends in authorship characteristics in KSSTA.

Methods

Two reviewers reviewed the table of contents of KSSTA and identified original papers from 1995, 2000, 2005, 2010, and 2015. The reviewers graded LOE from Levels I to IV using guidelines from the University of Oxford’s Centre for Evidence-Based Medicine. For each article, the total number of authors and country of author group were also analyzed.

Results

A total of 880 papers were analyzed. The proportions in LOE have stayed consistent throughout the study period (n.s.). There has been a significant increase in the number of published articles and the number of Level I and II studies (P?<?0.01). Therapeutic articles were the most common type. The mean number of authors per KSSTA article significantly increased from 3.9 to 5.7 over the 20-year period (P?<?0.01). The number of represented countries increased yearly and academic institutions from 40 different nationalities published articles in the Journal. Of the examined years, the percent of articles with international collaboration was 17.6%.

Conclusion

The proportion of LOE I and II articles published in KSSTA remains consistently high. Therapeutic studies are the most frequently published articles. There is an increase in international groups publishing in KSSTA.

Level of evidence

IV.
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Test shots at cloth and at human skin from autopsy material were performed with 7.62 mm Tokarev (TT), 9 mm Makarov (PM) and 9 × 19 mm Glock 19 pistols, using common ammunition.The largest central material defects, with fibre deformation in cotton, the largest burn holes in polyester, and also many fibre defects caused by the perforation of powder, were produced in shots from the TT at all distances. Tears in the cloth were longest in the case of the TT at 1 cm and were present at 3 cm, whereas the shots from the PM and the Glock 19 did not leave tears. There were small tears of the edges of the skin defect from shots fired from the TT at 1 and 3 cm. On cloth-soot deposits at 3 and 5 cm, the radial structures of soot resembled a cobweb (the TT), and radial branching structures (the PM) of soot were seen. Some shots from the PM left four shafts of rays of soot and formed the bullet wipe with four narrow and four wide sections, indicating the form of rifling. In the soot deposit from the Glock 19 with hexagonal rifling, hexagonal or polygonal or petal-like areas were visible. On skin, the soot zones were less distinct. The Glock 19 (at 3 and 5 cm) left a lot of gunpowder particles densely around the cloth and skin defect. The least powder left on the cloth and skin was by the PM.On histological tissue sections, in shots from the TT, a lot of soot and gunpowder residue particles in the epidermis and in both layers of the dermis, and intraepithelial tears and recesses containing soot, were seen. The PM left fine soot and only a few gunpowder particles in the epidermis and in the papillary layer of the dermis. The Glock 19 produced the least soot and a lot of gunpowder particles. The soot and most of the gunpowder particles were present on the tissue sections, which originated from the central area around the skin defect and were detected in the epidermis and in both layers of the dermis. Some tears and recesses in the epidermis were also seen. The further the distance from the centre of skin defect to the periphery, the depth of the penetration of the powder into the skin decreased.  相似文献   

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The VX2 tumor is a leporine anaplastic squamous cell carcinoma characterized by rapid growth, hypervascularity, and facile propagation in the skeletal muscle. Since its introduction over 70 years ago, it has been used to model a variety of malignancies, and is commonly employed by interventional radiologists in preclinical investigations of hepatocellular carcinoma. However, despite the widespread and lasting popularity of the model, there are few technical resources detailing its use. Herein, we present a comprehensive pictorial outline of the technical methodology for development, growth, propagation, and angiographic utilization of the rabbit VX2 liver tumor model.The rabbit VX2 tumor model has played a longstanding role in experimental oncology. Developed in 1930–1940 by Rous et al. (1, 2), the VX2 tumor is a virus-induced anaplastic squamous cell carcinoma characterized by hypervascularity, rapid growth, and easy propagation in the skeletal muscle (3, 4). Since its introduction, the tumor has been used to model cancers of the head and neck (5), kidney (6), brain (7), lung (8), urinary bladder (9), uterus (10), liver (11, 12), bone (13), and pancreas (14). The high growth rate and the relatively large size of rabbit vasculature render the model particularly well suited for use by interventional radiologists, and in recent years the model has been employed in numerous studies pertaining to the imaging and locoregional treatment of hepatocellular carcinoma (1519). However, despite the widespread and lasting popularity of the model, there are few, if any, comprehensive technical resources detailing its use, leaving many key procedural details to be conveyed anecdotally. Lack of a technical guide may also represent a barrier to entry of interventional radiologists into translational research. With that in mind, this review is intended to provide a complete pictorial overview of the development, growth, propagation, and angiographic utilization of the rabbit VX2 tumor model based on the experience of a single operator in order to serve as a reference for novice and experienced investigators alike.  相似文献   

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The purpose of this study was to evaluate whether the size, location, or number of fibroids affects therapeutic efficacy or complications of uterine artery embolization (UAE). Patients with symptomatic uterine fibroids (n = 101) were treated by selective bilateral UAE using 500- to 710-μm polyvinyl alcohol (PVA) particles. Baseline measures of clinical symptoms, sonography, and MRI taken before the procedure were compared to those taken 1, 3, 6, and 12 months later. Complications and outcomes were analyzed for associations with fibroid size, location, and number. Reductions in mean fibroid volume were similar in patients with single (66.6 ± 21.5%) and multiple (67.4 ± 25.0%) fibroids (p-value = 0.83). Menstrual improvement occurred in patients with single (93.3%) and multiple (72.2%) fibroids (p = 0.18). Changes in submucosal and other fibroids were not significantly different between the two groups (p’s > 0.56). Linear regression analysis between primary fibroid volume as independent variable and percentage reduction of fibroid volume after 1 year yielded an R2 of 0.083 and the model coefficient was not statistically significant (p = 0.072). Multivariate regression models revealed no statistically or clinically significant coefficients or odds ratios for three independent variables (primary fibroid size, total number, and fibroid location) and all outcome variables (percent reduction of uterus and fibroid volumes in 1 year, improvement of clinical symptoms [menstrual, bulk related, and urinary] in 1 year, and complications after UAE). In conclusion, neither the success rate nor the probability of complications was affected by the primary fibroid size, location, or total number of fibroids.  相似文献   

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Central or neurogenic diabetes insipidus (CDI) is due to deficient synthesis or secretion of antidiuretic hormone (ADH), also known as arginine vasopressin peptide (AVP). It is clinically characterised by polydipsia and polyuria (urine output >?30 mL/kg/day) of dilute urine (<?250 mOsm/L). It is the result of a defect in one of more sites involving the hypothalamic osmoreceptors, supraoptic or paraventricular nuclei of the hypothalamus, median eminence of the hypothalamus, infundibulum or the posterior pituitary gland. A focused MRI pituitary gland or sella protocol is essential. There are several neuroimaging correlates and causes of CDI, illustrated in this review. The most common causes are benign or malignant neoplasms of the hypothalamic-pituitary axis (25%), surgery (20%), head trauma (16%) or familial causes (10%). No cause is identified in up to 30% of cases. Knowledge of the anatomy and physiology of the hypothalamo-neurohypophyseal axis is crucial when evaluating a patient with CDI. Establishing the aetiology of CDI with MRI in combination with clinical and biochemical assessment facilitates appropriate targeted treatment. The aim of the pictorial review is to illustrate the wide variety of causes of CDI on neuroimaging, highlight the optimal MRI protocol and to revise the detailed neuroanatomy and neurophysiology required to interpret these studies.  相似文献   

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Endovascular coil occlusion of fusiform intracranial aneurysms without sacrifice of the parent artery can be technically challenging. Bridging of wide aneurysm necks with stents is common practice for side-wall aneurysms but is less frequently used for bifurcation aneurysms. We describe the technical aspects of the successful coil occlusion of a fusiform aneurysm of the upper basilar trunk, with preservation of the parent vessel. The procedure comprised the following steps: (a) stenting of the left V1- and proximal V2 segments; (b) simultaneous deployment of two Neuroform stents from both P1 segments down to the basilar artery (kissing stents) (c) using a TriSpan device to hold (d) three-dimensional electrolytically detachable coils in place and (e) filling the aneurysmal lumen mainly with fibered electrolytically detachable coils; and finally (f) cutting the extracorporeal part of both microguidewires below the skin level in both groins, leaving the microguidewires as they were used for the deployment of the stents in place, thus reaching from both P2 segments down to the basilar artery and further proximally.  相似文献   

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PURPOSE: The purpose of this study was to determine distinguishing features of three diseases that are distributed along the lymphatics. METHOD: CT scans of 40 patients with lymphangitic carcinomatosis, 41 with sarcoidosis, and 44 with malignant lymphoma were retrospectively reviewed. We evaluated the degree of involvement of the interlobular septa, bronchovascular structures, subpleural interstitium, and other CT findings. RESULTS: The number of thickened interlobular septa and the extent of involvement of the subpleural interstitium in lymphangitic carcinomatosis were higher than those in sarcoidosis and malignant lymphoma (p<0.0001). Nodules of >1 cm in diameter were more often seen in malignant lymphoma (41.0%) than in the other two diseases (p < 0.001). Bilateral distribution was more common in sarcoidosis (100%) than in the others (p<0.001). CONCLUSION: The major difference among lymphangitic carcinomatosis, sarcoidosis, and malignant lymphoma is the greater involvement of the interlobular septa and subpleural interstitium in lymphangitic carcinomatosis than in either sarcoidosis or malignant lymphoma.  相似文献   

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