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71.
72.
Postbiopsy renal transplant arteriovenous fistulas: color Doppler US characteristics 总被引:3,自引:0,他引:3
Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US. 相似文献
73.
Aimée E van Dijk Manon van Eijsden Karien Stronks Reinoud JBJ Gemke Tanja GM Vrijkotte 《BMC public health》2010,10(1):251
Background
Recent evidence, both animal and human, suggests that modifiable factors during fetal and infant development predispose for cardiovascular disease in adult life and that they may become possible future targets for prevention. One of these factors is maternal psychosocial stress, but so far, few prospective studies have been able to investigate the longer-term effects of stress in detail, i.e. effects in childhood. Therefore, our general aim is to study whether prenatal maternal psychosocial stress is associated with an adverse cardio-metabolic risk profile in the child at age five. 相似文献74.
75.
Front D; Ioselevsky G; Frenkel A; Even-Sapir E; Israel O; Kolodny GM; Feinsud M 《Radiology》1987,164(1):93-96
A single photon emission computed tomographic method was designed for the measurement of radiopharmaceutical uptake in brain tumors. Results of phantom studies showed a correlation coefficient of .99 when measured volume was compared with actual volume. The correlation coefficient for measured radioactivity concentration compared with the actual concentration was .97. In 13 meningiomas the correlation between in vivo SPECT measurements of uptake and in vitro measurements in samples of the same tumors removed surgically was .84; when two tumors that contained regions of necrosis and fibrosis were excluded it was .93. This method can be used for in vivo quantitative assessment of pharmacokinetics of labeled drug uptake in human brain tumors. 相似文献
76.
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78.
Canthaxanthin induces apoptosis in human cancer cell lines 总被引:3,自引:1,他引:2
Palozza P; Maggiano N; Calviello G; Lanza P; Piccioni E; Ranelletti FO; Bartoli GM 《Carcinogenesis》1998,19(2):373-376
To investigate the possibility that canthaxanthin inhibits cancer cell
growth by inducing apoptosis, human WiDr colon adenocarcinoma and SK- MEL-2
melanoma cells were treated with two different doses of the carotenoid for
48 h. Canthaxanthin was incorporated and/or associated to cells. The
treatment with the carotenoid caused growth inhibition in both cell types.
Concomitantly, apoptosis was induced. Increasing time of exposure and
carotenoid concentration, this effect was more pronounced. At 48 h, the
percentages of apoptotic cells were 13 and 15, using 1 microM
canthaxanthin, and 18 and 20, using 10 microM canthaxanthin in WiDr and
SK-MEL-2 cells, respectively. This study represents the first demonstration
that canthaxanthin is able to induce apoptosis in tumour cells.
相似文献
79.
Efficacy of Different β-Lactams against an Extended-Spectrum β-Lactamase-Producing Klebsiella pneumoniae Strain in the Rat Intra-Abdominal Abscess Model 总被引:1,自引:0,他引:1
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Louis B. Rice Joseph D. C. Yao Karin Klimm George M. Eliopoulos Robert C. Moellering Jr. 《Antimicrobial agents and chemotherapy》1991,35(6):1243-1244
Although standard-inoculum MICs were within the susceptible range for all compounds, cefoperazone, cefotaxime, and cefpirome were significantly less effective than imipenem or the combination of cefoperazone and sulbactam in the treatment of rat intra-abdominal abscesses due to an extended-spectrum beta-lactamase-producing strain of Klebsiella pneumoniae. 相似文献
80.
G M Eliopoulos E Reiszner M J Ferraro R C Moellering 《The Journal of antimicrobial chemotherapy》1987,20(5):671-675
The comparative in-vitro activity of A-56268 (TE-031), a new semisynthetic macrolide antibiotic, was assessed against approximately 400 bacterial isolates. The new drug demonstrated excellent activity against penicillin-susceptible streptococci (MIC90s less than or equal to 0.06 mg/l) and methicillin-susceptible staphylococci (MIC90 = 0.25 mg/l). Among other Gram-positive organisms tested, a significant number were resistant to A-56268 as well as to erythromycin and clindamycin. A-56268 was at least as active as erythromycin against Pasteurella multocida and Campylobacter jejuni, but was more active than erythromycin against Legionella spp. (MIC90 less than or equal to 0.06 mg/l), Bacteroides fragilis (MIC90 = 4 mg/l) and Bact. melaninogenicus (MIC90 less than or equal to 0.125 mg/l). Activity of A-56268 was pH dependent (more active at pH 7 than at pH 6) and was moderately affected by inoculum size. The drug was bactericidal against two strains of Streptococcus pyogenes tested, but exerted a bacteriostatic effect against Staphylococcus aureus and Str. faecalis. 相似文献