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排序方式: 共有964条查询结果,搜索用时 15 毫秒
41.
42.
Regional myocardial dysfunction: evaluation of patients with prior myocardial infarction with fast CT 总被引:1,自引:0,他引:1
Lipton MJ; Farmer DW; Killebrew EJ; Bouchard A; Dean PB; Ringertz HG; Higgins CB 《Radiology》1985,157(3):735-740
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics. 相似文献
43.
The hepatoprotective action of silymarin, the active principle extracted from the fruit of Silybum marianum (L.) Gaertn., in animals (dogs, rabbits, rats, mice) intoxicated with phalloidine is evident, both after protective and curative treatment. A dose of 15 mg/kg of silymarin protects every animal when given 60 min before the toxin. When injected 10 mim after phalloidine, a dose of 100 mg/kg of silymarin again provides total protection. However, as the time span between administration of the toxic substance and start of treatment increases, so the efficacy of silymarin decreases; after 30 min its curative effect is negligible. The histochemical and histoenzymological studies show that during intoxication of the mice by phalloidine, silymarin inhibits the effect of the toxic substance and regulates the functions of the hepatocyte, when given either 60 min before or 10 min after phalloidine. 相似文献
44.
R. C. Trost 《Psychopharmacology》1973,30(2):153-161
Independent groups of addicted rats were placed repeatedly in a conditioning procedure: pairings of non-rotatable activity wheels with periods of either 0–11 or 12–23 h of morphine deprivation. Controls consisted of a saline-injected group exposed to the same training stimuli and conditioning procedure, and a morphine addicted group not receiving such training. Subsequently, morphine-addicted animals were withdrawn until primary abstinence signs disappeared, and all groups were tested in unlocked wheels for differential activity resulting from reexposure to previous training environments.Experimental groups not only were found to exhibit significantly increased wheel turning over controls, but subjects having greater morphine deprivation during training were more resistant to extinction than a low deprivation group. Motivational interpretations and methodological artifacts in designs of this nature are discussed.A lengthy review of the literature encompassing the area of the present study, as well as a more thorough discussion of its theoretical aspects, were included in a Ph. D. thesis submitted to the Department of Psychology at the University of Denver, 1969, by the author. 相似文献
45.
Engikolai C. Krishnan Linda Trost Scott Aarons William R. Jewell 《The Journal of surgical research》1982,33(2):89-97
In recent years there has been an intense interest in understanding the mechanisms involved in immune modulation associated with dietary restriction. In this study we have investigated maturation of peripheral blood monocytes in morbidly obese patients using an in vitro culture system. At the end of the culture, the matured monocytes (macrophages) were quantitated. Though there was no detectable functional defect observed in the matured monocytes in vitro, there was a quantitative difference in maturation among the monocytes plated. The number of monocytes that matured into macrophages in obese patients was 3.29 ± 2.41 × 104 cells per milliliter of blood, as compared to 8.24 ± 3.14 × 104 per milliliter of blood in normal volunteers. This difference was found to be statistically significant at P < 0.001. These results indicate a possible development of an intrinsic defect among morbidly obese individuals. 相似文献
46.
PURPOSE: To evaluate the validity of a uniaxial accelerometer (MTI Actigraph) for measuring physical activity in people with acquired brain injury (ABI) using portable indirect calorimetry (Cosmed K4b(2)) as a criterion measure. METHODS: Fourteen people with ABI and related gait pattern impairment (age 32 +/- 8 yr) wore an MTI Actigraph that measured activity (counts.min(-1)) and a Cosmed K4b(2) that measured oxygen consumption (mL.kg(-1).min(-1)) during four activities: quiet sitting (QS) and comfortable paced (CP), brisk paced (BP), and fast paced (FP) walking. MET levels were predicted from Actigraph counts using a published equation and compared with Cosmed measures. Predicted METs for each of the 56 activity bouts (14 participants x 4 bouts) were classified (light, moderate, vigorous, or very vigorous intensity) and compared with Cosmed-based classifications. RESULTS: Repeated-measures ANOVA indicated that walking condition intensities were significantly different (P < 0.05) and the Actigraph detected the differences. Overall correlation between measured and predicted METs was positive, moderate, and significant (r = 0.74). Mean predicted METs were not significantly different from measured for CP and BP, but for FP walking, predicted METs were significantly less than measured (P < 0.05). The Actigraph correctly classified intensity for 76.8% of all activity bouts and 91.5% of light- and moderate-intensity bouts. CONCLUSIONS: Actigraph counts provide a valid index of activity across the intensities investigated in this study. For light to moderate activity, Actigraph-based estimates of METs are acceptable for group-level analysis and are a valid means of classifying activity intensity. The Actigraph significantly underestimated higher intensity activity, although, in practice, this limitation will have minimal impact on activity measurement of most community-dwelling people with ABI. 相似文献
47.
48.
Hepatocellular carcinoma with a skull metastasis is a rare clinical entity especially in Western countries. The authors of the present article report a case of solitary skull metastasis from hepatocellular carcinoma in a 75-year-old lady who had no prior history of the primary disease or liver dysfunction. The clinicopathological and radiological features are reviewed and discussed. 相似文献
49.
O'Brien MF Connolly SS Kelly DG O'Brien A Quinlan DM Mulvin DW 《Irish journal of medical science》2004,173(1):23-26
Background Patients with prostate cancer with a pre-operative prostate-specific antigen (PSA) τ;15ng/ml who undergo radical retropubic
prostatectomy (RRP) generally do not have a good outcome, yet may have organ-confined cancer and should be offered the option
of surgery.
Aim To assess the outcome of patients who underwent RRP with a pre-operative PSA ≥ 15ng/ml.
Methods Thirty-four patients, mean pre-operative PSA: 25.46ng/ml (15.03–76.6) and mean Gleason score: 6.4 (5–9) were assessed.
Results Two groups were identified. Group I: 41% (14/34) have no biochemical recurrence to mean follow up of 58 months (30–106).
Mean PSA: 18.8ng/ml (15.03–25.84). Mean Gleason score: 6.1 (5–7). Clinical stage: T1c in 80%. No patient had seminal vesicle
or lymph node involvement. Group II: 59% (20/34) have biochemical recurrence or died (3) from their disease to mean follow
up of 66 months (36–98). Mean PSA: 28.9ng/ml (15.28–76.6). Mean Gleason score: 6.7 (5–9). Clinical stage: T1c in 25%. Eleven
patients had seminal vesicle (8) involvement or positive lymph nodes (3) or both (2).
Conclusion RRP seems feasible in patients whose pre-operative PSA is between 15 and 25ng/ml with stage T1c, Gleason score ≤ 7 and negative
lymph node frozen section. 相似文献
50.
In myelodysplastic syndromes (MDS) a normal karyotype by cytogenetic analysis (CA) corresponds to a low cytogenetic risk for acute myeloid leukaemia (AML) evolution, a subset of patients however develops AML. We evaluated the use of interphase fluorescence in situ hybridisation (I-FISH) in 31 patients with evolution from primary MDS to AML and a normal CA at all stages of disease. Monosomy 7 was found in 4/31 cases, one patient had a terminal deletion 5q, each after AML evolution. The low frequency and unclear prognostic value of I-FISH anomalies in MDS related AML suggests that these alterations play a minor role for AML evolution. 相似文献