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171.
172.
Pathology in the urinary tract is one of the most frequent queries when children are referred for an ultrasound examination. Comprehensive ultrasound examinations can answer most clinical questions of the urogenital tract with minimal patient preparation and without the use of ionising radiation. Therefore, optimised imaging protocols should be available in all radiology departments where children are examined. This review suggests a preferred imaging protocol for urogenital imaging in children and gives an overview of the different structures of the urogenital tract, the normal age-related sonographic anatomy, and gives examples of the most commonly encountered diseases of the urogenital system in children.  相似文献   
173.
174.
胃癌手术患者2338例临床病理特征分析   总被引:2,自引:0,他引:2  
目的分析2 338例胃癌手术患者的临床病理特征。方法回顾性分析2 338例胃癌患者的临床资料。患者分为年龄≤40岁(A组)、41-65岁(B组)和>65岁(C组)三组,比较肿瘤部位、病理类型和临床分期。结果胃癌高发年龄41-65岁,男性比例高于女性。肿瘤多见于贲门胃底部(42.48%)。肿瘤以BormannⅡ型多见(75.44%),病理类型以腺癌为主(90.03%)。肿瘤分化程度以低分化为主(74.25%)。胃癌浸润深度以T3期主(64.6%)。淋巴结转移以N0、N1期为主(85.31%)。TNM分期以Ⅲ期为主(48.47%)。结论胃癌高发于41-65岁男性。胃癌病理分型以低分化腺癌最常见。确诊患者多为胃癌中晚期,胃癌早期诊断率有待提高。  相似文献   
175.
We report a case of hypoglossal nerve damage after shoulder hemiarthroplasty with the patient in «beach chair» position, performed with general anesthesia with orotracheal intubation, and without complications. An ultrasound-guided interscalene block was previously performed in an alert patient. After the intervention, the patient showed clinical symptomatology compatible with paralysis of the right hypoglossal nerve that completely disappeared after 4 weeks. Mechanisms such as hyperextension of the neck during intubation, endotracheal tube cuff pressure, excessive hyperextension, or head lateralization during surgery have been described as causes of this neurological damage. We discuss the causes, the associated factors and suggest preventive measures.  相似文献   
176.
A recently standardized ultrasound technique for measuring subcutaneous adipose tissue (SAT) was applied to normal-weight, overweight and obese persons. Eight measurement sites were used: upper abdomen, lower abdomen, erector spinae, distal triceps, brachioradialis, lateral thigh, front thigh and medial calf. Fat compression was avoided. Fat patterning in 38 participants (body mass index: 18.6–40.3 kgm?2; SAT thickness sums from eight sites: 12–245 mm) was evaluated using a software specifically designed for semi-automatic multiple thickness measurements in SAT (sound speed: 1450 m/s) that also quantifies embedded fibrous structures. With respect to ultrasound intra-observer results, the correlation coefficient ρ = 0.999 (p < 0.01), standard error of the estimate = 1.1 mm and 95% of measurements were within ±2.2 mm. For the normal-weight subgroup, the median measurement deviation was 0.43 mm (1.1% of mean thickness), and for the obese/overweight subgroup it was 0.89 mm (0.5%). The eight sites used here are suggested to represent inter-individual differences in SAT patterning. High measurement accuracy and reliability can be obtained in all groups, from lean to overweight and obese, provided that measurers are trained appropriately.  相似文献   
177.
Abstract

Objective. To compare hand US between systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) patients.

Methods. Hands (1st–5th metacarpophalangeal [MCP] and 1st–5th proximal interphalangeal [PIP] joints) and wrists (radiocarpal and distal radioulnar joints) of 62 “no rhupus” SLE and 60 RA patients were compared through US (linear probe, 6–18 MHz). The findings were compared to clinical, functional, serological outcomes, and disease activity indices.

Results. 2108 and 2040 joint recesses were evaluated in SLE and AR patients, respectively. Synovitis was found in 46.8% and 75% of wrists, 83.9% and 86.7% of MCPs and 58.1% and 70% of PIPs in the SLE and RA groups, respectively. More significant US findings were found in RA group. Greater values of synovitis (mm) in RA group were only found in the joint recesses of wrist (p < 0.001–0.002). In SLE group, US findings were associated with “puffy hands,” Health Assessment Questionnaire score and dynamometry. Twenty-two SLE patients (35.5%) had erosion in any of joints studied. SLE patient subgroup with US erosion was associated with hematological involvement and Jaccoud's arthropathy.

Conclusions. US of “no rhupus” SLE and RA patients is different, especially in wrists. In SLE patients the clinical variable most associated with US findings was “puffy hands.”  相似文献   
178.
179.
As ultrasound technology rapidly evolves and is used more frequently in every area of medical diagnosis and treatment, it may be overlooked as a potential vector in the transmission of a health care-associated infection. A survey on disinfection and hygiene practice in medical ultrasound was disseminated via the World Federation for Ultrasound in Medicine and Biology (WFUMB) to its six member federations and associated ultrasound societies globally. One thousand twenty-nine responses were obtained across a broad range of ultrasound practitioners. A total of 76% of respondents used transducer covers every time to scan open wounds and 71% when blood and bodily fluids were present or for an interventional procedure. Approved high-level disinfectants are not always used, even when blood comes into contact with the transducer or after endocavity scans. Alcohol-based wipes were used by many respondents to clean both external transducers and endocavity transducers. Open-ended responses indicated that a large caseload hindered the time required for cleaning and that access to clear guidelines would be beneficial. Global survey results indicate that some users do not comply with disinfection practice, and there is a gap in knowledge on basic infection prevention and control education within the ultrasound unit. As the infectious status of a patient is not often disclosed prior to an ultrasound examination, training in suitable protocols for the cleaning and disinfection of ultrasound equipment is imperative to mitigate the risk of potential infection.  相似文献   
180.
We aimed to reveal reasons for longitudinal variations of characteristic frequencies of electromyographic signals detected by surface longitudinal multi-electrodes. Since the terminal phases were reduced in bipolar recordings, wetested whether the frequency variations reflected the effects of the excitation origin and extinction as in monopolar recordings. A precise and fast convolution method to calculate the signals detected by a multielectrode was suggested. The contribution of different electrode poles was introduced in the impulse response. When a longitudinal multi-electrode with an even number of poles was positioned above the end-plate of asymmetrical fibres, the signal mainly reflected the processes of the excitation extinction. This increased the signal mean and median frequencies. Although the effects of origin and extinction of the excitation were significantly reduced in the spatially filtered signals, the frequency variations along the fibre reflected these intrinsic features of any skeletal muscle fibre of finite length.  相似文献   
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