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排序方式: 共有803条查询结果,搜索用时 203 毫秒
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Kuba K Zhang L Imai Y Arab S Chen M Maekawa Y Leschnik M Leibbrandt A Markovic M Makovic M Schwaighofer J Beetz N Musialek R Neely GG Komnenovic V Kolm U Metzler B Ricci R Hara H Meixner A Nghiem M Chen X Dawood F Wong KM Sarao R Cukerman E Kimura A Hein L Thalhammer J Liu PP Penninger JM 《Circulation research》2007,101(4):e32-e42
Apelin constitutes a novel endogenous peptide system suggested to be involved in a broad range of physiological functions, including cardiovascular function, heart development, control of fluid homeostasis, and obesity. Apelin is also a catalytic substrate for angiotensin-converting enzyme 2, the key severe acute respiratory syndrome receptor. The in vivo physiological role of Apelin is still elusive. Here we report the generation of Apelin gene-targeted mice. Apelin mutant mice are viable and fertile, appear healthy, and exhibit normal body weight, water and food intake, heart rates, and heart morphology. Intriguingly, aged Apelin knockout mice developed progressive impairment of cardiac contractility associated with systolic dysfunction in the absence of histological abnormalities. We also report that pressure overload induces upregulation of Apelin expression in the heart. Importantly, in pressure overload-induced heart failure, loss of Apelin did not significantly affect the hypertrophy response, but Apelin mutant mice developed progressive heart failure. Global gene expression arrays and hierarchical clustering of differentially expressed genes in hearts of banded Apelin(-/y) and Apelin(+/y) mice showed concerted upregulation of genes involved in extracellular matrix remodeling and muscle contraction. These genetic data show that the endogenous peptide Apelin is crucial to maintain cardiac contractility in pressure overload and aging. 相似文献
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Antioxidant vitamins preserve superoxide dismutase activities in gentamicin-induced nephrotoxicity 总被引:1,自引:0,他引:1
Kadkhodaee M Khastar H Arab HA Ghaznavi R Zahmatkesh M Mahdavi-Mazdeh M 《Transplantation proceedings》2007,39(4):864-865
OBJECTIVE: The clinical use of gentamicin (G) is limited due to its known nephrotoxic actions. Generation of reactive oxygen species has been proposed as a causative factor of cell death in G-induced acute renal failure (ARF). Previous studies using superoxide dismutase (SOD) mimetics have indirectly suggested a role for the superoxide ion in G-induced ARF. In this study, we directly measured the enzyme activities using in situ isolated kidneys seeking to investigate the effects of antioxidant therapy on preservation of endogenous antioxidant levels in ARF. METHODS: Thirty-five male Sprague-Dawley rats were randomly assigned to 5 groups: control, Tyrode-perfused; G, gentamicin (200 mg/L) added to the perfusate; G + vitamin E (Vit E; 100 mg/100 g BW, IM); G + vitamin C (Vit C) added to the drinking water for 3 days (200 mg/L) and to the perfusate (100 mg/L); G + Vit E + Vit C. SOD activities were determined in renal tissues based on NAPDH oxidation at 340 nm by spectrophotometry. RESULTS: SOD activity was significantly reduced in the G group compared with the controls (P<.05). Administration of Vit E alone or in combination with Vit C significantly preserved enzyme activity levels compared with the G group (P<.05). CONCLUSION: Antioxidant vitamins have a role in preservation of renal endogenous antioxidant activities, namely SOD, in G-induced nephrotoxicity. 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