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1.

Objectives

The aim of this study was to compare the effect of 10 min vs. 20 min passive rest post warm-up on performance in a 100 m freestyle time-trial.

Design

Randomized crossover.

Methods

Eleven competitive male swimmers performed two experimental trials on different days, consisting of 100 m freestyle time-trials following 10 min or 20 min passive rest after a standard 1200 m warm-up. Performance (time-trial), biomechanical (stroke length, stroke frequency, stroke index, propelling efficiency), physiological (blood lactate concentrations, heart rate, core and tympanic temperature), and psychophysiological (perceived effort) variables were assessed during both trials.

Results

Time-trial performance was faster after 10 min as opposed to 20 min passive rest (58.41 ± 1.99 s vs. 59.06 ± 1.86, p < 0.01). This was supported by strong effect sizes (d = 0.99) and the qualitative indication of “likely” positive effects. Heart rate before the time-trial was also higher after 10 min passive rest (89 ± 12 bpm vs. 82 ± 13 bpm; p < 0.01). Furthermore, net core temperature and oxygen uptake values before the time-trial were substantially lower after 20 min passive rest.

Conclusions

These data suggest that the 10 min post warm-up passive rest enhances 100 m freestyle performance when compared to a 20 min period. An improvement that appears to be mediated by the combined effects of a shorter post warm-up period on core temperature, heart rate and oxygen uptake.  相似文献   

2.

Purpose

To report our results of computed tomography-guided interstitial high-dose-rate (HDR) brachytherapy (BRT) in the treatment of patients with recurrent inoperable glioblastoma multiforme (GBM).

Patients and methods

Between 1995 and 2014, 135 patients were treated with interstitial HDR BRT for inoperable recurrent GBM located within previously irradiated volumes. Patient’s median age was 57.1 years (14–82 years). All patients were pretreated with surgery, postoperative external beam radiation therapy (EBRT) and systemic chemotherapy (ChT). The median recurrent tumor volume was 42?cm3 (2–207?cm3). The prescribed HDR dose was median 40?Gy (30–50?Gy) delivered in twice-daily fractions of 5.0?Gy over consecutive days. No repeat surgery or ChT was administered in conjunction with BRT. Survival from BRT, progression-free survival (PFS), toxicity as well as the impact of several prognostic factors were evaluated.

Results

At a median follow-up of 9.2 months, the median overall survival following BRT and the median PFS were 9.2 and 4.6 months, respectively. Of the prognostic variables evaluated in univariate analysis, extent of surgery at initial diagnosis, tumor volume at recurrence, as well as time from EBRT to BRT reached statistical significance, retained also in multivariate analysis. Eight patients (5.9%) developed treatment-associated complications including intracerebral bleeding in 4 patients (2.9%), symptomatic focal radionecrosis in 3 patients (2.2%), and severe convulsion in 1 patient (0.7%).

Conclusions

For patients with recurrent GBM, interstitial HDR BRT is an effective re-irradiation method for even larger tumors providing palliation without excessive toxicity.
  相似文献   

3.

Background

Assessment of bones, especially with respect to the question of species, individualization, gender and exposure time is an essential component of routine forensic work and involves recent as well as historical objects. Morphological and morphometric investigations allow at least a reasonable answer to these aspects; however, the identification of bones and skeletal findings often founders on a lack of knowledge of a presumed identity or methodological limitations. Findings can substantially contribute to an assessment of the historical context.

Objective

Based on the planned excavation of a Messerschmitt Bf 109, which according to contemporary witnesses crashed in 1945, the possibilities and limitations of forensic osteological expertise are illustrated.

Material and methods

The recovery of the aircraft wreck from earth contaminated by aviation fuel was carried by representatives of the German War Graves Commission (?Volksbund Deutsche Kriegsgräberfürsorge e. V.“). Subsequently, a forensic osteological assessment of skeletal fragments and evaluation of accompanying objects were carried out. Furthermore, chemical toxicological investigations of biological materials, accompanying objects and the surrounding environment as well as DNA analytical investigations on selected bones were carried out.

Results

The investigations showed these were parts of a young male skeleton with deformation of the ribs as well as fractures of the spine and extremities. The cause of death was consistent with a high speed trauma (aircraft crash) without recognizable heat damage. A complete DNA profile of a male person could be achieved, despite the skeletal parts being saturated with aviation fuel.

Conclusion

Despite many indications (e.g. identification tag, aircraft type, accompanying findings and DNA profile) and presumed identity, an identification could not be achieved due to a lack of reference materials. Noteworthy was the complete DNA profile despite, or perhaps because of, fuel-saturated bones.
  相似文献   

4.

Background

In order to evaluate the ability of traffic participants to drive, standardized and objective measurement methods are needed. In recent analyses it was shown that pupil function is a significant indicator of being under the influence of substances acting on the central nervous system.

Objective

The aim of this study was to answer the question whether it is possible to detect if a person is under the influence of drugs or medication based on pupil function.

Material and methods

In total 121 subjects were exposed to different light stimuli and an infrared pupillographic investigation of the eyes was carried out. The study cohort consisted of 41 healthy test subjects and 80 subjects under the influence of drugs or medication. Several neural network models with different network architectures were trained in a learning group, further analyzed in a verification sample and most importantly tested in an independent test sample. Specificity, sensitivity, negative and positive predictive values as well as the percentage of correctly predicted subjects were analyzed. A 95?% confidence interval (CI) was included for all performance measurements.

Results

A neural network model was found which performed with a specificity of 91?% (95% CI, 78–98?%), sensitivity 90?% (95% CI, 81–96?%), negative predictive value 85?% (95% CI, 72–94?%), positive predictive value 94?% (95% CI, 86–98?%) and a correct prediction was made for 90?% (95% CI, 83–95?%) of the subjects.

Conclusion

The results of this study clearly show that infrared pupillography provides excellent discrimination between healthy subjects and persons under the influence of drugs or medication in this specific setting.
  相似文献   

5.
6.
PurposeTo evaluate the impact of environmental and socioeconomic factors on outpatient cancellations and “no-show visits” (NSVs) in radiology.Materials and MethodsWe conducted a retrospective analysis by collecting environmental factor data related to outpatient radiology visits occurring between 2000 and 2015 at our multihospital academic institution. Appointment attendance records were joined with daily weather observations from the National Oceanic and Atmospheric Administration and estimated median income from the US Census American Community Survey. A multivariate logistic regression model was built to examine relationships between NSV rate and median income, commute distance, maximum daily temperature, and daily snowfall.ResultsThere were 270,574 (8.0%) cancellations and 87,407 (2.6%) NSVs among 3,379,947 scheduled outpatient radiology appointments and 575,206 unique patients from 2000 to 2015. Overall cancellation rates decreased from 14% to 8%, and NSV rates decreased from 6% to 1% as median income increased from $20,000 to $120,000 per year. In a multivariate model, the odds of NSV decreased 10.7% per $10,000 increase in median income (95% confidence interval [CI]: 10.3%-11.1%) and 2.0% per 10°F increase in maximum daily temperature (95% CI: 1.3%-1.6%). The odds of NSV increased 1.4% per 10-mile increase in commute distance (95% CI: 1.3%-1.6%) and 4.5% per 1-inch increase in daily snowfall (95% CI: 3.6%-5.3%). Commute distance was more strongly associated with NSV for those in the two lower tertiles of income than the highest tertile (P < .001).ConclusionEnvironmental factors are strongly associated with patients’ attendance at scheduled outpatient radiology examinations. Modeling of appointment failure risk based on environmental features can help increase the attendance of outpatient radiology appointments.  相似文献   

7.

Introduction

As part of the foundation of the German Hodgkin Study Group (GHSG) in 1978, a central radiotherapy (RT) reference centre was established to evaluate and to improve the quality of treatment. During the study generations, the quality assurance programs (QAP) were continued and adapted to the demands of each study. The purpose of this article is to demonstrate the results of the fifth study generation and to compare them to the previous findings.

Methods

With the start of the fourth GHSG study generation (HD10–12), a central prospective review of all diagnostic images was established to create an individual treatment plan for each early stage study patient. The quality of involved field RT was retrospectively evaluated by an expert panel of radiation oncologists. In the fifth study generation (HD13–15), the retrospective review of radiotherapy performed was refined and the results were compared with the findings of the fourth generation.

Results

The expert panel analyzed the RT planning and application of 1037 (28?%) patients (HD13 n = 465, HD14 n = 572). Simulation films were available in 85?% of cases and verification films in 87?%. RT was assessed as major violation in 46?% (HD13 = 38?%, HD14 = 52?%), minor violation in 9?% (HD13 = 9?%, HD14 = 9?%) and according to the protocol in 45?% (HD13 = 52?%, HD14 = 38?%).

Conclusion

The value for QAP of RT within the GHSG trials is well known. Still there were several protocol violations. In the future, the QAP program has to be adapted to the requirements of “modern RT” in malignant lymphoma.
  相似文献   

8.

Purpose

Technological advances in recent years have allowed the easy and accurate assessment of knee motion during athletic activities. Subsequently, thousands of studies have been published that greatly improved our understanding of the aetiology, surgical reconstruction techniques and prevention of anterior cruciate ligament (ACL) injuries. The purpose of this review is to summarize the evidence from biomechanical studies on ACL-related research.

Methods

High-impact articles that enhanced understanding of ACL injury aetiology, rehabilitation, prevention and adaptations after reconstruction were selected.

Results

The importance of restoring internal tibial rotation after ACL reconstruction has emerged in several studies. Criteria-based, individualized rehabilitation protocols have replaced the traditional time-based protocols. Excessive knee valgus, poor trunk control, excessive quadriceps forces and leg asymmetries have been identified as potential high risk biomechanical factors for ACL tear. Injury prevention programmes have emerged as low cost and effective means of preventing ACL injuries, particularly in female athletes.

Conclusion

As a result of biomechanical research, clinicians have a better understanding of ACL injury aetiology, prevention and rehabilitation. Athletes exhibiting neuromuscular deficits predisposing them to ACL injury can be identified and enrolled into prevention programmes. Clinicians should assess ACL-reconstructed patients for excessive internal tibial rotation that may lead to poor outcomes.

Level of evidence

III.  相似文献   

9.

Clinical issue

Autoimmune disorders of the central nervous system (CNS) are common but are also a heterogeneous group of diseases. The most common form is multiple sclerosis (MS), others are clinically isolated syndrome (CIS), acute demyelinating encephalomyelitis (ADEM) and neuromyelitis optica spectrum disorders (NMOSD). Paraneoplastic syndromes are rare and tumor-associated, they are not induced by direct invasion of tumor tissue but by tumor-associated autoantibodies mostly against specific CNS proteins, e.?g. limbic encephalitis and paraneoplastic cerebellar ataxia or degeneration.

Diagnostics, standard radiological methods, performance and achievements

The correct diagnosis of autoimmune and paraneoplastic syndromes can still be challenging. In addition to the patient history, clinical examination and blood as well as cerebrospinal fluid (CSF) tests, magnetic resonance imaging (MRI) is gaining importance in the diagnostics. It is important not only in primary diagnostics but also in follow-up and therapy monitoring, especially in MS with specific therapies to detect therapy complications, such as progressive multifocal leukoencephalopathy as early as possible. In paraneoplastic syndromes MRI can also be an important component in the diagnostics but can also initially be negative and typical signal changes become visible only in follow-up scans.

Practical recommendations

In paraneoplastic syndromes the correct diagnosis is based on laboratory tests for specific autoantibodies in serum and CSF.

Treatment

The treatment of autoimmune and paraneoplastic disorders of the CNS ranges from steroids and immunosuppressive agents to plasmapheresis, depending on the specific disorder.
  相似文献   

10.
In recent years the purely morphological magnetic resonance imaging (MRI) has been increasingly flanked by so-called functional imaging methods, such as diffusion-weighted imaging (DWI), to obtain additional information about tissue or pathological processes. This review article presents two MR techniques that can detect physiological processes in the human body. In contrast to all other functional MR imaging techniques, which are based on hydrogen protons, the first technique presented (X-nuclei imaging) uses the spin of other nuclei for imaging and consequently allows a completely different insight into the human body. In this article X?nuclei imaging is focused on sodium (23Na) MRI because it currently represents the main focus of research in this field due to the favorable MR properties of sodium. The second MR technique presented is the relatively novel chemical exchange saturation transfer (CEST) imaging that can detect exchange processes between protons in metabolites and protons in free water. The first part of this article introduces the basic technical principles, problems, advantages and disadvantages of these two MR techniques, whereas the second part highlights the potential clinical applications. Examples illustrate several potential applications in neuroimaging (e.?g. stroke and tumors), musculoskeletal imaging (e.?g. osteoarthritis and degenerative processes) and abdominal imaging (e.?g. kidneys and hypertension). Both techniques inherently contain an incredible potential for future imaging but are still on the threshold of clinical use and are currently under evaluation in many university centers.  相似文献   

11.
12.

Purpose

Although several anatomical landmarks have been proposed to obtain adequate femoral component alignment in total knee arthroplasty (TKA), there is still no consensus regarding the best way to correctly position the prosthetic component on the horizontal plane. A previous computed tomography (CT)-based study has demonstrated anatomical transepicondylar axis (aTEA) to be externally rotated relative to surgical transepicondylar axis (sTEA) of approximately 4.5°. In this study, it is described a new methodological approach to femoral component rotational positioning through the use of previously reported CT scan information and navigation.

Methods

Eight consecutive patients scheduled for navigated TKA were selected. Rotational placement of the femoral component was performed using navigation system. The femoral component was implanted setting 4.5° of internal rotation relative to the aTEA. Within 1 week from surgery, all patients underwent a CT scan, and the posterior condylar angle (PCA) was measured. A PCA of 0.0°, meaning component placement parallel to sTEA, was set as femoral rotational alignment target. Clinical evaluation was performed at a mean 14.3 months of follow-up with KOOS questionnaire.

Results

The mean PCA measured on post-operative CT images was 0.4° (SD 1.3°), meaning that the femoral component was averagely implanted with 0.4° of internal rotation relative to the sTEA. Seven out of eight cases (87.5 %) resulted to have within 1° deviation from the rotational alignment target. All patients but one reported good clinical results.

Conclusions

Relevant finding of the present study was that the use of navigation and aTEA as a reference demonstrated to be accurate to set up femoral component rotational positioning on the horizontal plane in TKA. Further study should be performed to confirm this conclusion.

Level of evidence

III.  相似文献   

13.

Purpose

To evaluate local control and survival after image-guided ablation of adrenal gland metastases.

Materials and Methods

Image-guided ablations of adrenal metastases measuring < 5 cm performed at 2 academic medical centers between July 2002 and June 2016 were analyzed. There were 51 procedures performed on 46 tumors (mean diameter 2.8 cm ± 1.1; range, 0.7–4.9 cm) in 38 patients (mean age 66 y; range, 41–80 y) with renal cell carcinoma (n = 17 patients; 45%), non–small cell lung cancer (n = 10 patients; 26%), and other primary malignancies (n = 11 patients; 29%). Treatment modalities included cryoablation (n = 30 procedures; 59%), radiofrequency ablation (n = 12 procedures; 24%) and microwave ablation (n = 9 procedures; 18%). Technical success, primary and secondary efficacy, local progression rate, local progression-free survival, and overall survival were assessed. Mean follow-up was 37 months (range, 2–128 months). Statistical analysis was performed with univariate Cox hazards regression and Kaplan-Meier analyses.

Results

Technical success, primary efficacy, and secondary efficacy were 96%, 72%, and 76%. Local progression rate during all follow-up was 25%. Local tumor progression-free survival at 1, 3, and 5 years was 82%, 69%, and 55%. Overall survival at 1, 3, and 5 years was 82%, 44%, and 34%. In 16 patients with isolated adrenal metastasis, median disease-free survival was 8 months; 4 patients had no evidence of disease during follow-up. Lung cancer was associated with decreased survival (hazard ratio 4.41, P = .002).

Conclusions

Image-guided ablation can achieve local control for adrenal metastases < 5 cm.  相似文献   

14.
This single-center prospective trial evaluated the safety and efficacy of percutaneous sclerotherapy for liver hemangiomas in 5 patients (1 man, 4 women; mean age 41.2 y) between 2016 and 2017. All patients were symptomatic (4 abdominal pain; 1 early satiety) and refused surgery. A single session of sclerotherapy with 20 cc mixture of 45 IU. Bleomycin in 10 cc distilled water and 10 cc Lipiodol (Ultra Fluide, Guerbet, France) was performed in all patients, achieving a 45.6%–71.1% lesion volume reduction and a 12.9%–41% reduction in the largest diameter of the lesion. Symptoms subsided in all patients during the 5-month follow-up period. Adverse events included a self-limited intraperitoneal hemorrhage in 1 patient.  相似文献   

15.

Background

The increasing proportion of elderly people in populations means that an increasing number of drivers with reduced executive functions due to age-related reasons have to be expected. Thus, an important question is how elderly drivers compensate for deficits in executive functioning and how these drivers can be identified.

Objective

This article is based on the hierarchical model of Michon and focuses on the analyses of characteristic behavior, attitudes and personality traits of elderly drivers who try to enhance their driving abilities based on individual compensation and coping strategies, compared to drivers who do not.

Material and methods

A sample of 42 drivers conducted driving exercises, as well as psychometric tests and a semi-structured interview, in order to obtain as broad a database as possible.

Results

The results of this study provide evidence that age per se is not a good predictor for fitness to drive.

Conclusion

The best predictor for the use of compensation strategies is the ability of elderly drivers to perceive and identify subjective mental stress and limitations of driving skills.
  相似文献   

16.
Laparoscopic sleeve gastrectomy is one of the most common bariatric procedures worldwide. It has recently gained in popularity because of a low complication rate, satisfactory resolution of comorbidities, and excellent weight loss outcome. This article reviews the surgical technique, expected postsurgical imaging appearance, and imaging findings of common complications after laparoscopic sleeve gastrectomy. Understanding of the surgical technique of laparoscopic sleeve gastrectomy and of the normal postsurgical anatomy allows accurate interpretation of imaging findings in cases of insufficient weight loss, weight regain, and postsurgical complications.  相似文献   

17.

Introduction

Astrocytomas are neoplasms that originate from glial cells. Anaplastic astrocytoma is classified as WHO III, with 27?% of the individuals with grade III astrocytoma living for at least 5 years even after treatment (radiation and chemotherapy). Photofrin II has been demonstrated to serve as a specific and selective radiosensitizing agent in both in vitro and in vivo tumor models.

Material and methods

This case report presents a woman suffering from an inoperable astrocytoma WHO III since 2004. The patient was treated with radiation therapy and Photofrin II as a radiosensitiser. The patient underwent irradiation with 40?+?20 Gy boost. The patient was given a single intravenous dose of 1 mg/kg Photofrin II 24 h prior to the initiation of radiation therapy.

Results

The patient is still alive without any significant side effect with a follow up of 106 months. MRI shows no evidence of disease.

Conclusion

The follow-up results are encouraging regarding the application of Photofrin II as an effective radiosensitizing agent in the treatment of inoperable WHO III astrocytoma.  相似文献   

18.
Mechanical thrombectomy with stent retrievers in acute stroke has emerged as the technique with the highest recanalization rate of therapeutic procedures available so far. Recently it was demonstrated that compared to intravenous rTPA alone, mechanical thrombectomy improves outcomes of patients with acute occlusions of intracranial arteries of the anterior circulation in several randomized clinical trials. In this article we will give an overview of the steps required for the thrombectomy procedure.  相似文献   

19.

Objective

This systematic review aimed to summarize research that assessed the associations between 20 m shuttle run test (20mSRT) performance and indicators of physiological, psychosocial and cognitive health among school-aged children and youth.

Design

Systematic review.

Methods

Five online databases were used to identify peer-reviewed studies published from 1980 to 2016. Studies were included if they matched these criteria: population (children and youth with a mean age of 5–17 years and/or in Grades 1–12), intervention/exposure (performance on the 20mSRT), and outcomes (health indicators: adiposity, cardiometabolic biomarkers, cognition, mental health, psychosocial health, self-esteem and physical self-perception, quality of life and wellbeing, bone health, musculoskeletal fitness, motor skill development, and injuries and/or harm). Narrative syntheses were applied to describe the results. A lack of homogeneity precluded a meta-analysis approach.

Results

Overall, 142 studies that determined an association between 20mSRT performance and a health indicator were identified, representing 319,311 children and youth from 32 countries. 20mSRT performance was favourably associated with indicators of adiposity, and some indicators of cardiometabolic, cognitive, and psychosocial health in boys and girls. Fewer studies examined the relationship between 20mSRT performance and measures of quality of life/wellbeing, mental health and motor skill development, and associations were generally inconsistent. The quality of the evidence ranged from very low to moderate across health indicators.

Conclusion and Implications

These findings support the use of the 20mSRT as a holistic indicator of population health in children and youth.  相似文献   

20.
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