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541.
纳米细菌研究   总被引:2,自引:0,他引:2  
纳米细菌(nanobacteria,Nb)是近年来才被发现的超微细菌.纳米细菌体积极其微小,其最小直径仅50 nm,大大低于理论上细菌体积的下限.因此纳米细菌在被发现的初期,其存在的真实性就受到许多学者的质疑,并且由此引发了一场关于微生物最小体积的争论.随着研究的不断深入,纳米细菌的生物学特性不断地被揭示,纳米细菌已经成为当前研究的一个热点问题.在医学界,纳米细菌被认为与肾结石、胆囊结石、动脉粥样硬化等病理性钙化疾病的发生有关系.本文在复习大量文献的基础上,针对纳米细菌的生物学特性以及纳米细菌与人类疾病等方面作一简单的回顾与总结.  相似文献   
542.
The athlete burnout syndrome: possible early signs   总被引:1,自引:0,他引:1  
Burnout has been identified as a concern in elite sport. The aim of the current study was to examine relationships among proposed early signs and the athlete burnout syndrome. Quantitative methods (i.e., questionnaire) were used to identify the level of burnout and perceptions of proposed early signs among New Zealand male semi- and fully-professional Rugby Union players (n = 199) aged 19 to 33 years (M = 25.19, SD = 2.98). Results indicated significant associations among proposed early signs and athlete burnout. Perceptions of adequate social support, competence and perceptions of control were negatively correlated with key characteristics of burnout. Perceived rugby and money hassles were positively correlated with key characteristics of burnout. This research provides support for the proposed early signs of burnout. Further research is needed to confirm these findings and investigate the nature of the relationship between these early signs and the burnout syndrome.  相似文献   
543.
544.
Budd-Chiari syndrome: CT observations   总被引:4,自引:0,他引:4  
Vogelzang  RL; Anschuetz  SL; Gore  RM 《Radiology》1987,163(2):329-333
The authors describe four patients with Budd-Chiari syndrome in whom contrast material-enhanced computed tomographic (CT) scans demonstrated low-density venous thrombosis in three sites not, to our knowledge, previously described with this modality. Thrombosis was seen in the portal circulation, the hepatic veins, and the intrahepatic inferior vena cava. It is known that concomitant portal vein thrombosis may be seen in 20% of patients with Budd-Chiari syndrome. Three of the four patients in the current study had this finding, one with extensive thrombosis of portal, mesenteric, and splenic veins and the other two with portal vein branch involvement. In one patient hepatic vein thrombosis was demonstrated with CT, and in three inferior vena cava clot was demonstrated. All four patients had the distinctive hepatic parenchymal contrast enhancement pattern seen in this condition, which the authors think may be at least partially caused by associated portal thrombosis. The presence of portal venous thrombosis should prompt the observer to consider the diagnosis of Budd-Chiari syndrome. Detection of hepatic vein clot confirms the diagnosis and may be seen in this condition in association with inferior vena cava thrombus.  相似文献   
545.
Preliminary investigations were conducted into the potential of magnetic resonance (MR) images for tissue classification of the breast on the basis of relative signal intensity. Multispectral techniques originally developed by the National Aeronautics and Space Administration for satellite image analysis were used in sequence selection, image data correction, image standardization, and image interpretation. Numerous sequence combinations with varying repetition times (TR) and echo times (TE) were considered, and a triplet was selected consisting of long TR/long TE, short TR/short TE, and an opposed phase sequence with intermediate TR and TE. Correction to remove system-imposed intensity inhomogeneities was required for all images. Image standardization based on fat and pectoral muscle signals was necessary for intercase comparisons. Multispectral images obtained based on this analysis suggest the feasibility of intensity-based image classification.  相似文献   
546.
Twenty-four patients with acute sigmoid diverticulitis and associated pelvic fluid collections seen on computed tomographic scans underwent percutaneous catheter drainage as an adjunct to surgical therapy. Fourteen of the 24 underwent a single-stage surgical procedure within 10 days of drainage. Five patients required two-stage surgical procedures because localized inflammatory changes precluded a primary resection despite the absence of a residual abscess at surgery. Two of the three remaining patients initially had no surgery, but they had recrudescences of their symptoms that required surgical drainage within 8 months. One patient in whom surgical resection was deferred remained asymptomatic 10 months after percutaneous drainage. A retrospective review of 87 patients undergoing surgery for diverticulitis suggested that the percentage of two-stage surgical procedures has decreased in the last 5-10 years, but there remains a substantial number of patients who might benefit from percutaneous catheter drainage of diverticular abscess of the sigmoid colon.  相似文献   
547.
用压电晶体传感器测定微量安乃近   总被引:1,自引:0,他引:1  
利用安乃近与碘反应,所产生的压电晶体频移与安乃近浓度成正比,可以测定低至2×10-7mol/L浓度的安乃近。频移与安乃近浓度符合关系式C(mol/L)=6.85×10-9△F(Hz)。常见的无机物及氨基酸等不干扰测定。  相似文献   
548.
Henoch Schönlein Purpura (HSP) is usually mild and self‐limiting, but it may be accompanied by severe complications such as bullous lesions. We describe the use of systemic prednisone in two patients with bullous lesions in HSP. The first patient presented with progressive bullous lesions distributed on the limbs that evolved into painful ulcers and necrosis. These were further complicated by a secondary skin infection. He then received 1 mg/kg/day prednisone after 9 days. Patient 2, a 10‐year‐old boy, presented with HSP and bullous lesions and received intravenous prednisone 1 mg/kg/day within 48 h after appearance of the bullous lesions. He recovered rapidly without any complications. Conclusion: To reduce the severity of HSP related bullous lesions and their sequelae, we would propose starting prednisone (1 mg/kg/day) as soon as the bullae appear. In addition to prednisone, analgesics and specialist skin care for bullae should be started.  相似文献   
549.
Aim: Urinary incontinence associated with dementia can result in medical comorbidities. We aimed to determine the prevalence of urinary incontinence and to identify the etiology and factors associated with urinary incontinence in dementia patients. Methods: Patients with an Mini‐Mental State Examination (MMSE) score of more than 10, attending the memory clinic were recruited. Basic demographic data, types and duration of dementia, use of cholinesterase inhibitor and other drugs with anticholinergic effects, carer stress and presence of urinary incontinence in the previous 6 months were recorded. Urodynamic studies were carried out in those patients with urinary incontinence. Results: One hundred and forty‐four subjects with a mean age of 78 years (standard deviation 6.8) were included. Forty‐eight (33.3%) had urinary incontinence. There was no statistically significant difference between continent and incontinent groups regarding age, MMSE, duration of dementia, use of cholinesterase inhibitor and of drugs with anticholinergic effects. Presence of nocturia of more than twice per night (odds ratio [OR] 4, 95% confidence interval [CI] 1.7, 9.2), use of walking aids (OR 2.6, 95% CI 1.1, 5.9) and male sex (OR 1.36, 95% CI 1.1, 5.2) were independent predictors of urinary incontinence. Urodynamic studies showed that 21 subjects had detrusor overactivity, 13 had bladder outlet obstruction, two with low compliance bladder, two with small bladder capacity, four with detrusor hyperactivity and impaired contractility. Conclusion: Urinary incontinence commonly occurs in dementia subjects. Poor mobility and presence of nocturia increase the risk of urinary incontinence. Correction of the possible reversible factors may help to reduce the prevalence of urinary incontinence in patients with dementia and reduce carer stress.  相似文献   
550.
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