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1.
The aim was to give a systematic presentation of physiologic and pathologic calcifications and ossifications in the face and
neck with a special emphasis on clinical relevance. In a sometimes subacute setting one should recognize specific calcifications
which often lead to important diagnoses such as fungal sinusitis or sclerosing labyrinthitis. In a more chronic situation
intraocular calcifications in small children are pathognomonic for retinoblastoma. Juxtatumoral sclerosis of the laryngeal
cartilage in laryngopharyngeal carcinoma is usually caused by tumor infiltration of the cartilage resulting in a higher tumor
stage and, this way, has a major impact on the therapeutical strategy. Calcified lymph nodes are mainly unspecific but can
be the result of tuberculosis or metastases of thyroid cancer. Cross-sectional imaging methods, most of all computed tomography,
are ideally suited to reveal head and neck calcifications and ossifications, especially those which are clinically relevant. 相似文献
2.
This article discusses the imaging manifestations of infectious and inflammatory conditions of the head and neck. Special attention is paid to the sites, routes of spread, and complications of neck infections. Because the clinical signs and symptoms and the complications of these conditions are often determined by the precise anatomic site involved, anatomic considerations are stressed. Familiarity with the fascial layers, spaces of the neck, and the contents of each space is helpful for this discussion. The fascial layers of the neck are important barriers to infection, and once infection is established, the fascial layers play a part in directing its spread. 相似文献
3.
目的:分离纯化幽门螺杆菌分泌和重组表达的细胞空泡毒素抗原( VacA)蛋白,并评价其致细胞空泡效应及致细胞凋亡效应。方法分别从幽门螺杆菌ATCC26695菌株培养上清和重组表达VacA蛋白的pQE30-VacA-E.coliM15基因工程菌中分离纯化VacA蛋白,经酸化后,以不同终浓度(5,10 ng/ml)分别与人胃腺癌AGS细胞共孵24 h,观察致空泡效应,并通过流式细胞术检测细胞凋亡。结果成功分离纯化出幽门螺杆菌分泌和重组表达的VacA蛋白;幽门螺杆菌分泌的VacA蛋白能显著引起AGS细胞的空泡样改变及凋亡(P<0.01),而重组表达的VacA蛋白致细胞空泡样改变及凋亡不显著( P>0.05)。结论幽门螺杆菌分泌的VacA蛋白有良好的空泡毒性及致凋亡效应,而重组表达的VacA蛋白无致空泡及凋亡效应,幽门螺杆菌分泌的VacA蛋白可用于VacA作用机制的研究。 相似文献
4.
化学武器公约( CWC)和生物武器公约( BWC)是为禁止生产、发展、储存和使用化学武器和生物武器而制定的国际公约。近年来,科学技术快速发展,知识交叉渗透,学科之间出现整合和融合,促进了科技进步和经济发展。其中化学和生物学融合在有力促进制药、健康卫生、绿色化学和环境保护等产业进步的同时,也对化学和生物武器公约的履约产生了重要的影响。该文综述了与化学武器和生物武器公约相关的化学和生物学融合进展,并分析其对公约履约的影响。 相似文献
5.
This study evaluated if the ventilatory response to exercise is impaired by the cramp position of rowing. Maximal oxygen uptake (VO2max), maximal expiratory volume (VEmax), and maximal heart rate (HRmax) during rowing and running were compared in 55 males (age, mean +/- SD, 21 +/- 3 years; height 176 +/- 5 cm; body mass 72 +/- 6 kg) and 18 females (age 20 +/- 2 years; height 164 +/- 5 cm; body mass 61 +/- 4 kg). VEmax was larger during rowing than during running (males, 157 +/- 16 vs. 147 +/- 13 L min(-1); 114 +/- 9 vs. 105 +/- 11 L min(-1), P<0.01). Also VO2max was larger during rowing than during running (males, 4.5 +/- 0.5 vs. 4.3 +/- 0.4 L min(-1); females, 3.3 +/- 0.4 vs. 3.2 +/- 0.4 L min(-1), P<0.01). However, HRmax was lower during rowing than during running (males, 194 +/- 8 vs. 198 +/- 11 beats min(-1); females, 192 +/- 6 vs. 196 +/- 8 beats min(-1), P<0.05). VEmax was correlated to body mass and fat-free mass, as was VO2max. Thus, the oxygen pulse (VO2max/HRmax) was larger during rowing than during running, while the ventilatory equivalent for oxygen (VEmax/VO2max) was similar. We showed that bending the body during rowing does not seem to impair ventilation either in males or in females. The results indicate that VEmax and VO2max relate to body size and fat-free mass for both females and males. The findings indicate that the involvement of more muscles, the entrainment, and the body position during rowing facilitates ventilation and venous return and lowers maximal heart rate. 相似文献
6.
Thirty-six patients with calcification or ossification at or around the coracoclavicular and coracoacromial regions were analyzed with regard to type, location, and configuration of the deposits and related clinical history. Calcification or ossification in the coracoclavicular region resulted largely from trauma (36%) or renal failure (28%). Trauma patients may develop punctate calcification or ossification but do not develop the tumoral type of calcification. About 5% of the renal failure patients had coracoclavicular ligament calcifications, one-half of which were of the tumoral type. Renal failure patients may have punctate or tumoral calcifications but do not develop ossification. 相似文献
7.
8.
在真核生物基因表达的转录后调节中,RNA结合蛋白( RBP)起着关键作用,很多RBP的异常与人类疾病的发生密切相关。自2000年的RNA免疫沉淀和芯片分析方法( RNA immunoprecipitation with differential display or microarray analysis , RIP-ChIP)出现以来,人们开始就RBP与RNA相互作用进行了系统而广泛的研究。经过改良和发展,基于体内实时紫外交联免疫沉淀法( ultraviolet crosslinking and immunoprecipitation , CLIP )、交联免疫沉淀cDNA文库高通量测序法( high-throughput sequencing of CLIP cDNA library , HITS-CLIP)、光催化核糖核苷增强交联和免疫沉淀法( photoactivatable-ribonucleoside-enhanced crosslinking and immunprecipitation , PAR-CLIP)以及提高个别核苷酸分辨率交联和免疫共沉淀法( individual nucleotide resolution CLIP , iCLIP)等RIP-ChIP衍生方法相继产生,使用这些方法,可以解析RBP的RNA识别特异性,而且通过与高通量测序技术结合,可以实现转录组尺度的RBP的靶序列的鉴定,分辨率也得到极大提高。该文就RNA与蛋白的相互作用的基本原理及其研究进展、相关技术存在的问题以及发展趋势进行简要综述。 相似文献
9.
Older prisoners are the fastest growing group of prisoners in many countries. The purpose of this study is to explore the phenomenon of detention of persons suffering from dementia. Medline searches were conducted for relevant articles, chapters and books published until August 2016. Search terms included dementia, elderly, prison and criminal. Publications found through this indexed search were reviewed for further relevant references. As results, there is a lack of data about elderly with dementia in prisons. Given the rise in the average age, it is reasonable to hypothesize that the number of older prisoners is growing. Moreover, some elderly are imprisoned with a concomitant cognitive impairment or psychiatric disorder while others will develop such diseases once incarcerated. At the present time, legal and social systems seem unprepared to handle the phenomenon of dementia in prison. As proposal, health assessments for older first time offenders should become a practice inside the correctional facilities and include an evaluation for specific health issues, such as psychiatric comorbidity and cognitive impairment. 相似文献
10.
In patients with renal failure, iodinated contrast agents may cause acute deterioration of the renal function and gadolinium-based contrast agents (GBCAs) may cause nephrogenic systemic fibrosis (NSF). The administration of a contrast agent must thus be reviewed for each patient and evaluation of renal function is paramount even though its estimation using formulas derived from the creatinine level may fluctuate. For iodinated contrast agents, contrast induced nephropathy is reduced by hydratation, preferably intravenous, when the GFR is less than 60 ml/min. The risk for intravenous injections is less than the risk for arterial injections, and the GFR threshold may be reduced to 45 ml/min. For gadolinium-based contrast agents, patients at risk for NSF are those with end-stage renal disease and patients undergoing dialysis. In such cases, the injection of a gadolinium-based contrast agent is only considered after a risk-benefit analysis has been completed, an alternate linear or macrocyclic agent issued and the dose limited to 0,1 mmol Gd/kg. Recently, recommendations from US and European agencies have converged. Learning objectives: to be familiar with the risk factors of CIN with iodinated contrast agents; to be familiar with hydration procedures for patients at risk of CIN; to be familiar with the diagnostic criteria of NSF; to be familiar with the classification of GBCA with regards to the risk of NSF; to be familiar with the contraindications of the different groups of GBCA. 相似文献
11.
《Journal of Science and Medicine in Sport》2020,23(9):831-835
ObjectivesTo examine the longitudinal associations and differences between self-reported and device-assessed physical activity (PA) and sedentary behaviour (SB), using a multifaceted statistical approach.DesignLongitudinal measurement burst.MethodsIn total, 52 university students (78% female) aged 18–38 years (mean = 21.94 ± 4.57 years) participated. The study consisted of three blocks of six days of measurement, during which participants wore an accelerometer on their wrist for the entire block, and self-reported their PA over the 6 days at the end of each block.ResultsMeaningful latent differences between methods were observed for moderate PA and SB across all three assessment periods, such that participants underreported the time spent in each activity. Bland–Altman plots revealed a positive mean difference for vigorous PA, with over-reporting increasing as mean levels increased. Negative mean differences were observed for all other intensities. Underreporting of moderate PA increased as the mean level increased, whereas for light PA and SB, underreporting decreased at high levels. Repeated measures correlations revealed a meaningful association for vigorous PA only, suggesting that as self-reported minutes increase so too do device-measured minutes.ConclusionsWe found evidence of cross-sectional and longitudinal differences and weak associations between self-reported and device-assessed PA and SB. Future work is needed to enhance the quality of self-reported methods to assess PA and SB (e.g., face and content validity), and consider improvements to the processing of device-based data. 相似文献
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13.
Interventional and intraoperative MR: review and update of techniques and clinical experience 总被引:4,自引:0,他引:4
The concept of interventional magnetic resonance imaging (MRI) is based on the integration of diagnostic and therapeutic procedures, favored by the combination of the excellent morphological and functional imaging characteristics of MRI. The spectrum of MRI-assisted interventions ranges from biopsies and intraoperative guidance to thermal ablation modalities and vascular interventions. The most relevant recently published experimental and clinical results are discussed. In the future, interventional MRI is expected to play an important role in interventional radiology, minimal invasive therapy and guidance of surgical procedures. However, the associated high costs require a careful evaluation of its potentials in order to ensure cost-effective medical care. 相似文献
14.
缺血缺氧与线粒体DNA损伤 总被引:6,自引:1,他引:6
线粒体DNA(mtDNA)编码细胞色素氧化酶Ⅰ、Ⅱ、Ⅲ(COX-Ⅰ、COX-Ⅱ、COX-Ⅲ)及ATP酶亚单位6、8(ATPase6.8)等蛋白质及多肽,控制着氧化磷酸化和ATP合成。缺血缺氧时氧化磷酸化障碍,ATP合成减少,COX-Ⅰ-mRNA、NADH辅酶Q氧化还原酶-mRNA(NDmRNA)转录水平升高,基因上调。缺血缺氧引起线粒体DNA突变率升高,mtDNA^4977、mtDNA^7436、mtDNA^10423缺失,ATPase6-8亚单位基因突变。葡萄糖糖酵解酶、热休克蛋白(HSP)、磷酶甘油还原酶B(PGM-B)及基因疗法可提高机体对缺氧的耐受性和适应性。 相似文献
15.
Purpose: To estimate the pain and anxiety experienced by women in relation to mammography, and how radiographers can improve the situation for women attending for the X-ray examination.Methods: The study recruited 170 women aged between 40 and 69 years. Structured questionnaires were used: McGill Pain Questionnaire; State–Trait Anxiety Inventory (STAI), and Questionnaire for Predictor Variables.Results: During mammography, 66.5% of the women reported feeling pain, but most of them described the pain as mild or moderate. There is a correlation between anxiety and pain after mammography (P<0.01).Conclusions: Anxiety and pain in connection with mammography were real enough, but were not perceived as a great problem by most of the women in the study. 相似文献
16.
《The Physician and sportsmedicine》2013,41(1):142-157
AbstractOsteoporosis-related fractures represent a major health concern, particularly in elderly populations. Direct and indirect costs (amounting to nearly $17 billion in 2005), increased morbidity, and loss of independence place substantial burden on the health care system. Observational studies have shown that a physically active lifestyle is associated with a 30% to 50% decrease in vertebral or hip fractures, and a recent meta-analysis that determined the effects of exercise on fracture incidence further confirmed these results. However, because no randomized controlled exercise trials have selected fractures as a primary endpoint, causality between a sedentary lifestyle and fractures may be potentially confounded by participants' poor health status. With regard to fall reduction and bone strength as the main surrogates for fracture risk, many randomized controlled trials and corresponding meta-analyses have reported significant positive outcomes. Interestingly, no study that has assessed fall-related injuries has focused specifically on interventions that aimed to reduce fall impact. There is ongoing debate as to which factor, osteoporosis or falls, is more important for fracture prevention. This may be dependent on the region prone to fracture and the subjects' health status. In randomized controlled trials on exercise, the type, mode, and composition of exercise parameters are predictors of study outcome. Unfortunately, many exercise trials on fall prevention have not adequately described the exercise protocol used, which makes it difficult to determine which fall prevention protocol was most effective. A recent meta-analysis recommended Tai Chi and/or a mix of balance and resistance exercises for fall prevention. More sophisticated protocols are required to impact bone strength. Corresponding state-of-the-art protocols have focused on periodized high-impact/high-intensity resistance protocols performed at least twice per week. In the frail elderly, high-frequency/high-cycle number exercise programs with low-to-moderate strain intensity may also positively affect bone strength. 相似文献
17.
《Gait & posture》2019
BackgroundNumerous investigations have attempted to link the incidence and risk of non-contact anterior cruciate ligament injuries to specific intrinsic and extrinsic mechanisms. However, these are often measured in isolation.Research questionThis study utilizes a dynamical systems approach to investigate differences in coordination and coordination variability between segments and joints in anticipated and unanticipated sidestepping, a task linked to a high risk of non-contact anterior cruciate ligament injuries.MethodsFull body, three-dimensional kinematics and knee kinetic data were collected on 22 male collegiate soccer players during anticipated and unanticipated sidestepping tasks. A modified vector coding technique was used to quantify coordination and coordination variability of the trunk and pelvis segments and the hip and knee joints.ResultsSagittal and frontal plane trunk-pelvis coordination were more in-phase during unanticipated sidestepping. Sagittal plane hip-knee and hip (rotation)-knee (flexion/extension) coordination were more in-phase with the knee dominating the movement during unanticipated sidestepping (P < 0.05). Coordination variability was greater in unanticipated sidestepping for trunk (flexion)-pelvis (tilt), trunk (lateral flexion)-pelvis (obliquity), hip (flexion/extension)-knee (flexion/extension) and hip (rotation)-knee (flexion/extension) (P < 0.05). In unanticipated sidestepping where there is limited time to pre-plan the movement, multiple kinematic solutions and high coordinative variability is required to achieve the task.SignificanceOur results suggest that coordination becomes more in-phase and the variability of this coordination increases as a function of task complexity and reduced planning time as that which occurs in unanticipated sporting task scenarios. Consequently, injury prevention programs must incorporate perceptual components in order to optimise planning time and coordinate appropriate postural adjustments to reduce external knee joint loading and subsequent injury risk in sport. 相似文献
18.
Brealey SD King DG Hahn S Crowe M Williams P Rutter P Crane S 《Clinical radiology》2005,60(6):710-717
AIM: To assess selectively trained radiographers and consultant radiologists reporting plain radiographs for the Accident and Emergency Department (A&E) and general practitioners (GPs) within a typical hospital setting. METHODS: Two radiographers, a group of eight consultant radiologists, and a reference standard radiologist independently reported under controlled conditions a retrospectively selected, random, stratified sample of 400 A&E and 400 GP plain radiographs. An independent consultant radiologist judged whether the radiographer and radiologist reports agreed with the reference standard report. Clinicians then assessed whether radiographer and radiologist incorrect reports affected confidence in their diagnosis and treatment plans, and patient outcome. RESULTS: For A&E and GP plain radiographs, respectively, there was a 1% (95% confidence interval (CI) -2 to 5) and 4% (95% CI -1 to 8) difference in reporting accuracy between the two professional groups. For both A&E and GP cases there was an 8% difference in the clinicians' confidence in their diagnosis based on radiographer or radiologist incorrect reports. For A&E and GP cases, respectively, there was a 2% and 8% difference in the clinicians' confidence in their management plans based on radiographer or radiologist incorrect reports. For A&E and GP cases, respectively, there was a 1% and 11% difference in effect on patient outcome of radiographer or radiologist incorrect reports. CONCLUSION: There is the potential to extend the reporting role of selectively trained radiographers to include plain radiographs for all A&E and GP patients. Further research conducted during clinical practice at a number of sites is recommended. 相似文献
19.
Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality worldwide. COPD is defined
by irreversible airflow obstruction. It is a heterogeneous disease affecting the airways (i.e. chronic bronchitis, airway
collapse), the parenchyma (i.e. hyperinflation, air trapping and emphysematous destruction) as well as the vasculature (i.e.
hypoxic vasoconstriction, rarefication and pulmonary arterial hypertension) with different severity during the course of the
disease. These different aspects of COPD can be best addressed by imaging using a combination of morphological and functional
techniques. Three-dimensional high-resolution computed tomography (3D-HRCT) is the technique of choice for morphological imaging
of the lung parenchyma and airways. This morphological information is to be accomplished by functional information about perfusion,
regional lung mechanics, and ventilation mainly provided by MRI. The comprehensive diagnostic possibilities of CT complemented
by MRI will allow for a more sensitive detection, phenotype-driven characterization and dedicated therapy monitoring of COPD
as presented in this review. 相似文献
20.
Kawczyński A Nie H Jaskólska A Jaskólski A Arendt-Nielsen L Madeleine P 《Scandinavian journal of medicine & science in sports》2007,17(2):172-179
The aim of this study was to investigate changes in mechanomyographic (MMG) and the surface electromyographic (EMG) signals during and after fatiguing shoulder eccentric contractions in a group consisting of 12 males and 12 females. Exerted force, MMG, EMG, pain and rate of perceived exertion were assessed before, during and after repeated high-intensity eccentric exercises. Bouts of eccentric contractions caused a decrease in the exerted force for males (P<0.05) and an increase in the rate of perceived exertion and pain for both genders (P<0.05). During eccentric exercise, the root mean square (RMS) values of the MMG signal increased (P<0.05). The mean power frequency (MPF) values of the EMG signal decreased at the end of each eccentric bout for both genders (P<0.05); the decrease was higher for females compared with males (P<0.05). Immediately after eccentric exercise in static abduction of the upper limbs, the MMG RMS and MPF values increased (P<0.05). The present study showed that (1) neuromuscular changes associated with pain and changes in muscle stiffness and (2) changes in motor units strategy during fatigue development in shoulder muscle are reflected in the MMG and EMG signals. 相似文献