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排序方式: 共有651条查询结果,搜索用时 15 毫秒
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Verreault J Maisonneuve F Dietz R Sonne C Letcher RJ 《Environmental toxicology and chemistry / SETAC》2009,28(1):162-172
A captive study was performed with Greenland sledge dogs (Canis familiaris) fed a naturally organohalogen-contaminated diet (Greenland minke whale [Balaenoptera acutorostrata] blubber; exposed group) or a control diet (pork fat; control group). The catalytic activity of major xenobiotic-metabolizing phase I and II hepatic microsomal enzymes was assessed. Relative to control dogs, ethoxyresorufin-O-deethylase (EROD) activity in exposed dogs was twofold higher (p = 0.001). Testosterone hydroxylation yielded 6beta- and 16beta-hydroxy (OH) testosterone and androstenedione, with higher rates of production (23-27%; p < or = 0.03) in the exposed individuals. In the exposed dogs, epoxide hydrolase (EH) activity was 31% higher (p = 0.02) relative to the control dogs, whereas uridine diphosphoglucuronosyl transferase (UDPGT) activity was not different (p = 0.62). When the exposed and control dogs were combined, the summed (sigma) plasma concentrations of OH-polychlorinated biphenyl (PCB) congeners were predicted by plasma sigmaPCB concentrations and EROD activity (p < or = 0.04), whereas testosterone hydroxylase, EH, and UDPGT activities were not significant predictors of these concentrations. Consistent results were found for individual OH-PCB congeners and their theoretical precursor PCBs (e.g., 4-OH-CB-187 and CB-183, and 4-OH-CB-146 and CB-146) and for EROD activity. No association was found between sigmaOH-polybrominated diphenyl ether (PBDE) and sigmaPBDE plasma concentrations, or between potential precursor-metabolite pairs, and the enzyme activities. The present results suggest that liver microsomal EROD activity and plasma PCB concentrations have a greater (e.g., relative to EH activity) predictive power for the occurrence of plasma OH-PCB residues in sledge dogs. These results also suggest that plasma OH-PBDEs likely are not products of cytochrome P450-mediated transformation but, rather, are accumulated via the diet. 相似文献
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SB Cho SJ Lee S Cho SH Oh WS Chung JM Kang YK Kim DH Kim 《Journal of the European Academy of Dermatology and Venereology》2010,24(8):921-925
Background Non‐ablative 1550‐nm erbium‐doped fractional photothermolysis systems (FPS) and 10 600‐nm carbon dioxide fractional laser systems (CO2 FS) have been effectively used to treat scars. Objective We compared the efficacy and safety of single‐session treatments of FPS and CO2 FS for acne scars through a randomized, split‐face, evaluator‐blinded study. Methods Eight patients with acne scars were enrolled in this study. Half of each subject’s face was treated with FPS and the other half was treated with CO2 FS. We used a quartile grading scale for evaluations. Results At 3 months after the treatment, the mean grade of improvement based on clinical assessment was 2.0 ± 0.5 for FPS and 2.5 ± 0.8 for CO2 FS. On each side treated by FPS and CO2 FS, the mean duration of post‐therapy crusting and scaling was 2.3 and 7.4 days respectively and that of post‐therapy erythema was 7.5 and 11.5 days respectively. The mean VAS pain score was 3.9 ± 2.0 with the FPS and 7.0 ± 2.0 with the CO2 FS. Conclusion We demonstrated the efficacy and safety of single‐session acne scar treatment using FPS and CO2 FS in East Asian patients. We believe that our study could be used as an essential reference when choosing laser modalities for scar treatment. 相似文献
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Successful intracytoplasmic sperm injection with spermatozoa from a patient with dysplasia of the fibrous sheath and chronic respiratory disease 总被引:5,自引:4,他引:1
The present report describes a successful intracytoplasmic sperm injection
(ICSI) procedure performed with immotile spermatozoa from a young man with
a combination of dysplasia of the fibrous sheath and dynein deficiency, a
recently described variant of the immotile cilia syndrome. This methodology
provides the only suitable solution for these patients in whom all other
assisted fertilization technologies have previously failed, and opens the
possibilities for treatment of male infertility due to severe, irreversible
sperm defects such as the one reported here.
相似文献
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Helle S. Sonne Per D. Christensen Berit Muan J?rgen Assentoft Trond Haider Bent ?. Kristensen 《The International Journal of Cardiac Imaging》1995,11(1):47-53
A clinical study has been performed to investigate the influence of different administration procedures on the degree of contrast enhancement of the left ventricle. The administration variables assessed included Albunex® injection rate, arm position, flushing rate and flushing fluid. Twenty-four healthy male volunteers were included. Compared to an injection rate of 1 ml/sec an injection rate of Albunex® of 2 ml/sec caused an earlier appearance of contrast in the right ventricle (1 heart beat), whereas transpulmonary passage was not influenced. Horizontal arm position caused a delay in time to peak intensity of 2 to 3 heart beats in both systole and diastole as compared to elevated arm position. Injection rate of 1 ml/sec compared to 2 ml/sec caused a higher peak intensity and mean area under the curve and a longer mean time to peak intensity and transit time. Differences varied from 6 to 230 grey level units out of mean values of 2500. All the observed differences were small and thus probably of no clinical importance.The present study indicates that improvements in the pressure stability characteristics of the albumin microspheres in Albunex® have been achieved. This implies that a simple administration procedure can be used. It is recommended that the contrast agent, after resuspension, is injected through a three-way stop cock cannula, followed by 10 ml of saline for flushing. The cannulas or syringes used should be no smaller than 20 G. The injection rate should be 1–2 ml/sec, depending on the diameter of the cannula. By using this procedure, a reliable transpulmonary passage and left ventricular opacification may be obtained. 相似文献