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Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are commonly encountered in nontrauma surgical patients. Depending on the etiology of the patient's surgical illness (ruptured abdominal aortic aneurysm, acute pancreatitis, burns, etc.), both the incidence and mortality of IAH/ACS may be quite high. Recent advances in both the diagnosis and resuscitation of these surgical patients have resulted in significantly improved survival over that seen in years past. Intra-abdominal pressure measurements should be performed in any surgical patient who demonstrates risk factors for IAH/ACS.  相似文献   
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Muscle tissue composition accounting for the relative content of muscle fibers and intramuscular adipose and loose fibrous tissues can be efficiently analyzed and quantified using images from spiral computed tomography (S-CT) technology and the associated distribution of Hounsfield unit (HU) values. Muscle density distribution, especially when including the whole muscle volume, provides remarkable information on the muscle condition. Different physiological and pathological scenarios can be depicted using the muscle characterization technique based on the HU values and the definition of appropriate intervals and the association of such intervals to different colors. Using this method atrophy, degeneration, and restoration in denervated muscle undergoing electrical stimulation treatments can be clearly displayed and monitored. Moreover, finite element methods are employed to calculate Young's modulus on the patella bone and to analyze correlation between muscle contraction and bone strength changes. The reliability of this tool though depends on S-CT assessment and calibration. To assess imaging quality and the use of HU values to display muscle composition, different S-CT devices are compared using a Quasar body scanner. Density distributions and volumes of various calibration elements such as lung, polyethylene, water equivalent, and trabecular and dense bone are measured with different scanning protocols and at different points of time. The results show that every scanned element undergoes HU variations, which are greater for materials at the extremes of the HU scale, such as dense bone and lung inhale. Moreover, S-CT scanning with low tube voltages (80 KV) produces inaccurate HU values especially in bones. In conclusion, 3-D modeling techniques based on S-CT scanning is a powerful follow-up tool that may provide structural information at the millimeter scale, and thus may drive choice and timing to validate rehabilitation protocols.  相似文献   
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BACKGROUND: Heart failure is common in diabetes and ischaemic heart disease is the most likely link. Still, it has been suggested that the relation extends beyond such disease. METHODS: 7060 subjects with two or more visits in the Reykjavík Study were followed--during 30 years from 1967. All underwent oral glucose tolerance tests. Disease status was defined according to the glycaemic level and presence of heart failure. The incidence and predictive factors for these diseases were determined. FINDINGS: Age and sex standardized incidence of heart failure was 5.3/1000/year, of diabetes 4.6/1000/year and abnormal glucose regulation 12.6/1000/year. Body mass index (BMI) and fasting glucose predicted the development of these conditions (p<0.001). Increasing fasting glucose by 1 mmol/l increased the risk for heart failure by 14% (p=0.04) after adjusting for IHD, BMI and other risk factors for CVD. There was a strong association between diabetes and heart failure, OR 3.0 (2.3-4.0), and abnormal glucose regulation and heart failure, OR 1.8 (1.5-2.3). Diabetes and heart failure were, however, not independent predictors of each other. INTERPRETATION: There was an independent relationship between increases in fasting glucose and development of heart failure. BMI was a strong predictor of heart failure. Although fasting glucose and BMI were significant risk factors for glucose disturbances and heart failure the conditions themselves did not independently predict each other.  相似文献   
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Defective glycosylation and immune complex (IC) formation may be of primary importance in immunoglobulin A nephropathy (IgAN) pathogenesis. The aim of this study was to determine whether defective IgA1 glycosylation might support renal deposition of IgA and disease activity. IgA was isolated from the serum of 44 IgAN patients and 46 controls and glycosylation analysed by ELISA using glycan‐specific lectins. IgA was measured by immunodiffusion and immune complexes by ELISA. IgA subclasses in IC deposits in kidney glomeruli were identified by immunohistochemical methods. A significant increase in N‐acetylgalactosamine (GalNAc) in terminal position (p = 0.02) observed in some of the IgAN patients, became more pronounced when sialic acid was removed from IgA1, indicating enhanced expression of α‐2,6‐sialyltransferase in patients compared with controls (p < 0.0001). Patients with defective galactosylation had lower serum IgA than other IgAN patients (p = 0.003). IgAN patients with both IgA1 and IgA2 glomerular deposits (21.7%) had increased GalNAc in terminal position (p = 0.003). Taken together, our results show that increased IgA glycosylation in IgAN associates with low levels of IgA, concomitant IgA1 and IgA2 glomerular deposits and poor clinical outcome.  相似文献   
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PURPOSE: Although eye drops are the most common form of ocular drugs, they have several limitations. Drug absorption into the eye is, in general, less than 5%, addition of preservatives is often necessary, and many drugs cannot be formulated as eye drops. Formulating ocular drugs as powder may solve these problems. The aim of this study was to investigate ocular irritation in rabbits following powder administration. METHODS: Timolol maleate (TM) powder was administered to pigmented lop rabbits. Both pure TM powder and freeze-dried with PVP-polymer (2.4% of mass) were tested in 1.0- and 0.1-mg doses. Additionally, 4 rabbits received 0.1 mg of the pure powder 3 times a day for 8 d. Redness of the bulbar conjunctiva and the amount of discharge was rated from photographs (0-3 points, randomized and masked evaluation). The 8-d experiment additionally included examination with a slit lamp and examination of hematoxylin-eosin stained sections of eyes with light microscopy. RESULTS: No serious or irreversible signs of irritation were noted. Doses of 1.0 mg were more irritating than 0.1-mg doses. There was no detectable difference in irritation between pure or freeze-dried powder. Slit-lamp examination, surface photographs and histology showed a negligible difference between drug and control eyes following the 8-d experiment. CONCLUSIONS: The results suggest that 0.1 mg of timolol powder does not irritate the eye and that testing topical timolol powder in humans is feasible.  相似文献   
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OBJECTIVE: We estimated the prevalence, incidence and risk factors of left ventricular hypertrophy (LVH) in a prospective cohort study of 26 489 participants. MATERIAL AND METHODS: The LVH was defined as Minnesota Code 310 on electrocardiogram (ECG). Everyone with this code at first visit was defined as a prevalence case and those who developed it between subsequent visits were incidence cases. The comparison cohort were all other participants in the Reykjavik Study stages I-V. RESULTS: A total of 297 men and 49 women were found to have LVH of 3.2% and 0.5%, respectively. The incidence was 25 per 1000 per year amongst men and six per 1000 per year amongst women. Prevalence in both genders increased with increasing age. Risk factors at the time of diagnosis were systolic blood pressure [odds ratio (OR) per mmHg 1.02; 95% confidence interval (CI): 1.01-1.03], age (OR per year 1.04; 95% CI: 1.02-1.05), silent myocardial infarction (MI) (OR 3.18; 95% CI: 1.39-7.27) and ST-T changes (OR 3.06; 95% CI: 2.14-4.38) amongst men and systolic blood pressure and age for women with similar odds ratio. Predictive factors for acquiring LVH were systolic blood pressure [incidence ratio (IR) 1.01; 95% CI: 1.01-1.02] and angina with ECG changes (IR 2.33; 95% CI: 1.08-5.02) amongst men and systolic blood pressure amongst women (IR 1.03; 95% CI: 1.01-1.04). The risk for coronary mortality was significantly increased amongst women with hypertrophy [hazard ratio (HR) 3.07; 95% CI: 1.5-6.31] and their total survival was poorer with increasing time from diagnosis of LVH (HR 2.17; 95% CI: 1.36-3.48). CONCLUSIONS: We conclude that the presence of LVH and its appearance is associated with age and increased blood pressure amongst both genders. Women with LVH have poorer survival than other women and they are at threefold risk of dying of ischaemic heart disease.  相似文献   
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