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排序方式: 共有1001条查询结果,搜索用时 15 毫秒
91.
Secondary neoplastic infiltration of the myocardium diagnosed by two-dimensional echocardiography in seven cases with anatomic confirmation 总被引:1,自引:0,他引:1
C Lestuzzi S Biasi G L Nicolosi D Lodeville D Pavan R Collazzo A Guindani D Zanuttini 《Journal of the American College of Cardiology》1987,9(2):439-445
In seven patients with different types of neoplasm, secondary myocardial infiltration was diagnosed in vivo by two-dimensional echocardiography and confirmed by direct inspection. In all patients, clinical and electrocardiographic findings were suggestive but nonspecific for myocardial involvement. Two patients had cardiac tamponade and three had pericardial effusion. In three patients, the echocardiographic diagnosis made it possible to plan specific therapy. Clinical, electrocardiographic and echocardiographic aspects are discussed. A two-dimensional echocardiographic examination should be performed in all patients when cardiac metastatic involvement is suspected from clinical electrocardiographic findings, because the in vivo diagnosis of such a condition may have important therapeutic implications for such patients. 相似文献
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JJ Korelitz ; AE Williams ; MP Busch ; TF Zuck ; HE Ownby ; LJ Matijas ; DJ Wright 《Transfusion》1994,34(10):870-876
BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a “random process,” as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect. 相似文献
95.
Total radical trapping antioxidant potential (TRAP) and exercise 总被引:1,自引:0,他引:1
Sharpe PC; Duly EB; MacAuley D; McCrum EE; Mulholland C; Stott G; Boreham CA; Kennedy G; Evans AE; Trinick TR 《QJM : monthly journal of the Association of Physicians》1996,89(3):223-228
The relationship between physical activity, physical fitness and total
radical trapping antioxidant potential (TRAP) was examined in the Northern
Ireland Health and Activity Survey. This was a cross-sectional population
study (n = 1600) using a two-stage probability sample of the population.
TRAP was calculated using the sum of the individual serum antioxidant
concentrations (urate, protein thiols, ascorbate, alpha tocopherol and
bilirubin) multiplied by their respective stoichiometric values. Physical
fitness was determined by estimation of VO2max by extrapolation from
submaximal oxygen uptake, and physical activity was recorded by
computer-assisted interview. Mean serum TRAP concentrations were
significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared
to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female
smokers had significantly lower TRAP values than non-smokers (males p <
0.0001, females p = 0.02). In females, there was a positive relationship of
TRAP with age (p < 0.001) and body mass index (p < 0.001) but a
negative relationship with physical fitness (p < 0.05). The known
beneficial effects of exercise and activity do not appear to be directly
mediated through increased antioxidant status.
相似文献
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98.
Tei指数与主动脉瓣狭窄患者心功能不全症状的关系 总被引:3,自引:0,他引:3
目的探讨主动脉瓣狭窄患者Tei指数与临床心功能不全症状的关系。方法对92例主动脉瓣狭窄患者[男53例,女39例,平均年龄(66±9)岁],进行超声心动图检查。根据患者是否具有临床心功能不全症状将其分为两组,A组为无症状或症状轻微组(NYHAⅠ/Ⅱ,63例),B组为症状严重组(NYHAⅢ/Ⅳ,29例)。结果两组之间反映主动脉瓣狭窄程度的指标(主动脉瓣面积、跨主动脉瓣峰值速度和压差)差异无显著性意义。B组患者左室心肌质量和左室心肌质量指数均高于A组,分别为(311±83)g对(277±70)g(P=0.044),及(181±45)g/m2对(156±39)g/m2(P=0.008)。反映左室收缩功能的指标射血分数以及反映左室舒张功能的指标E波减速时间、E/A值两组之间差异无显著性意义。B组患者的Tei指数值明显高于A组(0.64±0.26对0.40±0.08,P<0.001)。A组中Tei指数≥0.45者占22.2%,而B组中该比例高达79.3%(P<0.001)。结论主动脉瓣狭窄伴严重心功能不全症状者Tei指数明显高于无症状或仅具有轻微症状者。Tei指数≥0.45在识别症状明显的主动脉瓣狭窄患者方面优于其他常用的超声心动图指标,对主动脉瓣狭窄临床治疗决策具有重要价值。 相似文献
99.
De Conti F Piovesana P Nicolosi G Lafisca N Mantovani E Viena P Pantaleoni A 《Echocardiography (Mount Kisco, N.Y.)》1997,14(4):387-392
Systolic anterior motion of the mitral valve (MV) with dynamic left ventricular (LV) outflow tract obstruction is a well known phenomenon in hypertrophic cardiomyopathy, or other forms of hyper-dynamic LV function associated with hypovolemic states, or LV hypertrophy. We report three patients with MV prolapse in the absence of the above predisposing factors, who developed an LV outflow dynamic gradient during acute transient myocardial ischemia. An interaction between structural abnormalities of the mitral apparatus and ischemia-dependent LV shape deformity most likely accounted for the outflow gradient. 相似文献
100.
Anton R. Edmund Swetha Kambalapally Thomas A. WilsonRobert J. Nicolosi 《Toxicology in vitro》2011,25(1):185-190
Although, nanometer-scale semi-conductor quantum dots (QDs) have attracted widespread interest in medical diagnosis and treatment, many can have intrinsic toxicities, especially those composed of CdSe, associated with their elemental composition. Using our self-assembling nanoemulsion (SANE) formulations which we have previously reported to be composed of non-toxic components, i.e., such as vegetable oil, surfactant and water, we hypothesized that their appropriate utilization would reduce the toxicity of QDs by encapsulating the CdSe QDs in our (SANE) system using a modified phase-inversion temperature (PIT) method. SANE encapsulation of the QDs did not alter their emission wavelength of 600 nm which remained unchanged during the encapsulation process. In contrast, zeta potential of encapsulated QDs was reduced from −30 to −6.59 mV, which we have previously reported to be associated with beneficial properties (increased bioavailability and efficacy) for SANE-encapsulated bioactives such as pharmaceuticals. Relative to the untreated controls, the viability of HeLa cells exposed for 48 h to un-encapsulated CdSe QDs at a concentration of 115 μg/mL was 22.7 ± 1.7% (p < 0.05). In contrast, the percentage of viable HeLa cells following exposure to SANE-encapsulated CdSe QDs at the same concentration was 91.6 ± 3.5% (p < 0.05) or a 307% increase in the number of viable cells (p < 0.05). When the dose of CdSe QDs was increased to 230 μg/mL, the percentage of viable HeLa cells after exposure to the un-encapsulated CdSe QDs was 16.1 ± 1.3% compared to controls (p < 0.05). In contrast, at the same increased concentration (230 μg/mL) of un-encapsulated CdSe QDs, the percentage of viable HeLa cells following exposure to SANE-encapsulated CdSe QDs was 87.9 ± 3.3% relative to controls (p < 0.05) or a 448% increase in the number of viable cells (p < 0.05). Exposure of HeLa cells to a nanoblank, (nanoemulsion without QDs), showed no significant effect on cell viability (97.2 ± 2.5%) compared to control cell culture. In conclusion, application of our SANE technology for encapsulating QDs increased cell viability of cells exposed to CdSe QDs while maintaining the original emission wavelength and therefore may be applied to reduce QD toxicity. 相似文献