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1.
V Aerra M Kuduvalli AN Moloto AK Srinivasan AD Grayson BM Fabri AY Oo 《Journal of cardiothoracic surgery》2006,1(1):6-5
Background
Atrial fibrillation can occur in up to 40% of patients undergoing coronary surgery. 相似文献2.
Paul Wexberg MD BM Richard Pacher MD Suzanne Rdler MD Katharina Kiss MD Gilbert Beran MD Michael Grimm MD Gerald Maurer MD Dietmar Glogar MD FESC 《The Journal of heart and lung transplantation》2002,21(12):583-1263
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation. 相似文献
3.
Streptolysin O enhances keratinocyte migration and proliferation and promotes skin organ culture wound healing in vitro 总被引:1,自引:0,他引:1
Marjana Tomic-Canic PhD ; Stephen W. Mamber PhD ; Olivera Stojadinovic MD ; Brian Lee MSc ; Nadezda Radoja PhD ; John McMichael PhD 《Wound repair and regeneration》2007,15(1):71-79
ML-05, a modified form of the hemolytic and cytotoxic bacterial toxin, streptolysin O, is currently being investigated as a treatment for collagen-related disorders such as scleroderma and fibrosis. Furthermore, ML-05 may be effective in promoting wound healing and alleviating the formation of hypertrophic scars and keloids. To investigate the effects of ML-05 on wound-healing processes, in vitro wound-healing scratch assays (using human primary epidermal keratinocytes and dermal fibroblasts) and a human skin organ culture wound model were utilized. ML-05 markedly enhanced keratinocyte migration and proliferation in wound scratch assays. ML-05 did not affect either proliferation or migration of dermal fibroblasts, indicating that ML-05's effects on cell migration/proliferation may be keratinocyte-specific. ML-05 was tested in a dose-dependent manner in a skin organ culture wound model using two different application methods: Through the culture media (dermal exposure) or direct topical treatment of the wound surface. ML-05 was found to accelerate wound healing as measured by reepithelialization, particularly after topical application. Therefore, ML-05 may have potential as a wound-healing agent that promotes reepithelialization through stimulation of keratinocyte migration and proliferation. 相似文献
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A randomized controlled trial of sedation in the critically ill 总被引:2,自引:0,他引:2
LYNN PARKINSON RSCN JULIE HUGHES RSCN REA GILL MSc IMOGEN BILLINGHAM BM FRCA JANE RATCLIFFE MB ChB FRCP & IMTI CHOONARA MD MRCP 《Paediatric anaesthesia》1997,7(5):405-510
A randomized controlled trial comparing: a) a combination of oral chloral hydrate and promethazine to b) a continuous intravenous midazolam infusion, for maintenance sedation in critically ill children, was carried out. The level of sedation was assessed four hourly using a specifically devized sedation scale. Forty-four children entered the study of whom two were subsequently excluded. The number of satisfactory assessments (desired and actual levels of sedation equal) was significantly greater in the chloral hydrate and promethazine group (Chi-squared P <0.01; confidence intervals of the difference 0.06 to 0.20). The number of assessments at level 5 on the sedation scale (patient restless/distressed) was significantly greater in the midazolam group (Chi-squared P <0.05). The total number of satisfactory assessments in the two groups were only 61 and 48% respectively, suggesting that sedation can be considerably improved. Chloral hydrate and promethazine are more effective than midazolam as maintenance sedation in critically ill children. It is possible to prospectively study the efficacy of sedative drugs in critically ill children. 相似文献
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The computerized database system described was initially developed in 1986 to facilitate analysis of retrospective head and neck cancer data from the Royal Adelaide Hospital Department of Otolaryngology. This has now been expanded to become an on-going patient information management system. It is based on the dBase-III-Plus database package and is implemented on an IBM XT compatible computer. The system was designed to be used by staff without specialist computer skills and is therefore largely “menu-driven.” The main functions include patient record creation, update, and retrieval, and the production of reports including graphical presentations. There is also a powerful but easy to use query facility. The system has already provided much useful epidemiological material but is now beginning to fulfill an even more important role in patient follow-up and in assisting evaluation of alternative treatment protocols. 相似文献
10.
Genome multiplication is a typical feature of trophoblast giant cell (TGC) development in many species. Elevated nuclear DNA contents can be achieved by modified cell cycles with a complete lack of mitosis (endoreduplication) or with incomplete mitoses. The aim of this study is to characterize genome multiplication in the alpaca TGC. Placental tissues of gestation days 150, 264 and 347 (near term) and term placentae were processed for light microscopy and for transmission electron microscopy. Each TGC showed many nuclear profiles. Observation of serial sections revealed that TGCs are truly multinucleate with several highly lobulated nuclei. Feulgen staining showed that TGC nuclei have a higher DNA content than nuclei of other trophoblast cells. The number of argyrophilic nucleolar organizer regions (AgNORs) in nuclear profiles of TGC was between 15 and 100, while other trophoblast cells showed 1 or 2 AgNORs. Large multipolar mitotic figures with maximal diameters of 80 mum were observed in the alpaca placentas on gestation days 264 and 347. No cytokinesis was seen in TGC. The results show that the mode of genome multiplication in the alpaca TGC is mitotic polyploidization. Subsequent acytokinetic mitoses may lead to an accumulation of chromosomes and centrioles in TGC. With increasing ploidy levels, the shape of these polyploidizing mitoses becomes more irregular. The restitution of nuclei after these complex multipolar mitoses is likely to result in the irregular nuclear shape in TGC. 相似文献