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91.
92.
Bradyarrhythmia requiring permanent pacing after heart transplantation remains a common problem. Sinus node dysfunction is the most common indication, and late onset of atrioventricular (AV) block has rarely been reported. We report the case of a patient who developed advanced AV block at 41 months after transplantation. Right bundle branch block with progressive increase of QRS complex duration was noted in serial electrocardiograms. At the time of late AV block development, the patient did not have acute rejection and coronary angiogram was normal. The mechanism of late onset of AV block is unclear, but it may be caused by progressive conduction. 相似文献
93.
Background
Reports on childhood cancer survivors estimated cumulative probability of developing secondary neoplasms vary from 3,3% to 25% at 25 years from diagnosis, and the risk of developing another cancer to several times greater than in the general population. 相似文献94.
胰岛素瘤的超声诊断:与其他诊断方法比较 总被引:1,自引:0,他引:1
目的:探讨超声等方法对胰岛素瘤的定位诊断价值。材料和方法:对42例经过手术和病理证实的胰岛素瘤患者术前定位诊断的各种方法进行回顾性分析,并与其他诊断方法对比分析其各自的定位符合率。结果:定位诊断符合率分别为B超31%(13/42)、EUS55.6%(5/9)、IOUS100%(10/10)、超声引导下PTPC100%(3/3)、CT59.5%(25/42)、MRI50%(6/12)、选择性DSA27.3%(3/11)及ASVS90%(9/10)。彩超(CDUS)对胰岛素瘤良、恶性有鉴别作用。结论:遵循循序渐进原则,先后选用B超(含CDUS)、EUS、CT等已可解决80%以上的定位诊断,然后再做MRI及ASVS;对仍未作出定位者,只要定性诊断明确即有手术探查指征,因为IOUS能提供可靠的定位信息。 相似文献
95.
Chong-Sheng Chen Youssef Jounaidi David J Waxman 《Drug metabolism and disposition》2005,33(9):1261-1267
The anticancer prodrug ifosfamide (IFA) contains a chiral phosphorous atom and is administered in the clinic as a racemic mixture of R-IFA and S-IFA. Hepatic cytochrome P450 (P450) enzymes exhibit enantioselective preferences in the metabolism of R-IFA and S-IFA; however, the impact of this selectivity on P450-dependent anticancer activity is not known. Presently, the metabolism and cytotoxicity of R-IFA and S-IFA were determined in 9L gliosarcoma and Chinese hamster ovary tumor cells expressing an IFA-activating P450 enzyme and by in vitro steady-state kinetic analysis using cDNA-expressed P450 enzymes. Tumor cells expressing P450 enzyme CYP3A4 were the most sensitive to R-IFA cytotoxicity, whereas tumor cells expressing CYP2B1 or CYP2B6 were most sensitive to cyclophosphamide (CPA), an isomer of IFA. Correspondingly, CYP3A4-expressing cells and cDNA-expressed CYP3A4 metabolized R-IFA to yield the active, 4-hydroxylated metabolite at a 2- to 3-fold higher rate than they metabolized S-IFA or CPA. CYP2B cells and cDNA-expressed CYP2B enzymes metabolized CPA almost exclusively by 4-hydroxylation, whereas R-IFA and S-IFA were substantially converted to inactive, N-dechloroethylated metabolites. Further investigation revealed that CYP3A1, a rat enzyme, exhibited superior kinetic properties compared with the human enzyme CYP3A4, with R-IFA and S-IFA both metabolized with high catalytic efficiency by 4-hydroxylation and with a K(m) value of 200 microM, approximately 5-fold lower than CYP3A4. Based on these kinetic parameters and metabolic profiles, R-IFA is expected to exert greater anticancer activity than S-IFA or CPA against tumors that express CYP3A enzymes, whereas tumors expressing CYP2B enzymes may be more sensitive to CPA treatment. 相似文献
96.
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98.
Birgitta Malmberg Göran Kecklund Björn Karlson Roger Persson Per Flisberg Palle Ørbaek 《BMC health services research》2010,10(1):239
Background
It is well known that physicians' night-call duty may cause impaired performance and adverse effects on subjective health, but there is limited knowledge about effects on sleep duration and recovery time. In recent years occupational stress and impaired well-being among anaesthesiologists have been frequently reported for in the scientific literature. Given their main focus on handling patients with life-threatening conditions, when on call, one might expect sleep and recovery to be negatively affected by work, especially in this specialist group. The aim of the present study was to examine whether a 16-hour night-call schedule allowed for sufficient recovery in anaesthesiologists compared with other physician specialists handling less life-threatening conditions, when on call. 相似文献99.
David Berrigan Linda W Pickle Jennifer Dill 《International journal of health geographics》2010,9(1):20
Background
Past studies of associations between measures of the built environment, particularly street connectivity, and active transportation (AT) or leisure walking/bicycling have largely failed to account for spatial autocorrelation of connectivity variables and have seldom examined both the propensity for AT and its duration in a coherent fashion. Such efforts could improve our understanding of the spatial and behavioral aspects of AT. We analyzed spatially identified data from Los Angeles and San Diego Counties collected as part of the 2001 California Health Interview Survey. 相似文献100.
Sebastiana Z. Kalula G. H. Swingler A. A. Sayer M. Badri M. Ferreira 《The journal of nutrition, health & aging》2010,14(4):319-323