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排序方式: 共有7412条查询结果,搜索用时 15 毫秒
81.
Chow B. J. W Beanlands R. S Lee A 《世界核心医学期刊文摘》2006,2(5):51-51
目的:本研究旨在比较踏车运动(TEX)与潘生丁负荷对心肌摄取及潴留13N-氨的影响。背景:负荷诱发心肌灌注缺损的大小和严重程度具有重要的临床意义。由于心肌对氨的摄取和潴留似乎与心肌血流灌注、心肌存活和代谢有关,因此运动负荷将比潘生丁负荷诱发出更大范围的心肌灌注缺损。方法:26例患者接受TEX和潘生丁负荷13N-氨正电子发射断层扫描(PET)检查。用17节段模型及5分评分法对图像进行分析。计算负荷状态总评分(SSS)、静息状态总评分(SRS)和差值总评分(SDS)。根据异常灌注阈值的70%定量测定左室(LV)缺损的大小。结果:与潘生丁负荷相… 相似文献
82.
Edward Chow Alison Ling Lori Davis Tony Panzarella Cyril Danjoux 《Radiotherapy and oncology》2005,75(1):64-69
BACKGROUND AND PURPOSE: To examine the incidence of pain flare following external beam radiotherapy and to determine what constitutes a meaningful change in pain scores in the treatment of bone metastases. PATIENTS AND METHODS: Patients with bone metastases treated with external beam radiotherapy were asked to score their pain on a scale of 0-10 before the treatment (baseline), daily during the treatment and for 10 days after completion of external beam radiation. Pain flare was defined as a two-point increase from baseline pain in the pain scale of 0-10 with no decrease in analgesic intake or a 25% increase in analgesic intake employing daily oral morphine equivalent with no decrease in pain score. To distinguish pain flare from progression of pain, we required the pain score and analgesic intake to return back to baseline levels after the increase/flare. They were also asked to indicate if their pain changed during that time compared to pre-treatment level. The change in pain score was compared with patient perception. RESULTS: Eighty-eight patients were evaluated in this study. There were 49 male and 39 female patients with the median age of 70 years. Twelve of 88 patients (14%) had pain flare on day 1. The overall incidence of pain flare during the study period ranged from 2 to 16%. A total of 797 pain scorings were obtained. Patients perceived an improvement in pain when their self-reported pain score decreased by at least two points. CONCLUSIONS: Our study confirms the occurrence of pain flare following the external beam radiotherapy in the treatment of bone metastases. Further studies are required to predict who are at risk for flare. Appropriate measures can be taken to alleviate the pain flare. The finding in the meaningful change in pain scores supports the investigator-defined partial response used in some clinical trials. 相似文献
83.
Resveratrol inhibits rhabdomyosarcoma cell proliferation. 总被引:2,自引:0,他引:2
A W Chow G Murillo C Yu R B van Breemen A W Boddie J M Pezzuto T K Das Gupta R G Mehta 《European journal of cancer prevention》2005,14(4):351-356
Rhabdomysarcoma is the most common soft tissue tumour in children under the age of 15. Although the introduction of multimodal treatment programmes, including chemotherapy, radiation therapy and excision have increased the overall survival, the chemotherapeutic agents currently used for the treatment of rhabdomyosarcoma exhibit considerable toxicity. The aim of this study was to investigate the effects and possible mechanism(s) of action of resveratrol on human embryonal rhabdomyosarcoma (RD) cells. Resveratrol is a natural polyphenolic compound produced in a number of edible plants and has received considerable attention as a potential chemopreventive and/or chemotherapeutic agent against various types of cancers. In the present study, resveratrol was shown to inhibit cell proliferation of RD cells in a dose-dependent manner with an IC50 of 48.1 micromol/l and induce an arrest in the S/G2 phase of the cell cycle. As evident from immunocytochemical data, resveratrol treatment increased the size of the RD cells. Furthermore, resveratrol treatment resulted in a significant downregulation of cyclin B expression as demonstrated by western blot analyses. In conclusion, the present study shows that resveratrol exerts a strong inhibition of rhabdomyosarcoma cell proliferation in part by arresting cells in S/G2 phase of the cell cycle. These findings warrant further investigation to establish potential use of resveratrol as a relatively non-toxic chemotherapeutic agent for the treatment of rhabdomyosarcoma. 相似文献
84.
Tim Du Kelly B. Choi Anada Silva George R. Golding Linda Pelude Romeo Hizon Ghada N. Al-Rawahi James Brooks Blanda Chow Jun C. Collet Jeannette L. Comeau Ian Davis Gerald A. Evans Charles Frenette Guanghong Han Jennie Johnstone Pamela Kibsey Kevin C. Katz Joanne M. Langley Bonita E. Lee Yves Longtin Dominik Mertz Jessica Minion Michelle Science Jocelyn A. Srigley Paula Stagg Kathryn N. Suh Nisha Thampi Alice Wong Susy S. Hota 《Emerging infectious diseases》2022,28(6):1128
We investigated epidemiologic and molecular characteristics of healthcare-associated (HA) and community-associated (CA) Clostridioides difficile infection (CDI) among adult patients in Canadian Nosocomial Infection Surveillance Program hospitals during 2015–2019. The study encompassed 18,455 CDI cases, 13,735 (74.4%) HA and 4,720 (25.6%) CA. During 2015–2019, HA CDI rates decreased by 23.8%, whereas CA decreased by 18.8%. HA CDI was significantly associated with increased 30-day all-cause mortality as compared with CA CDI (p<0.01). Of 2,506 isolates analyzed, the most common ribotypes (RTs) were RT027, RT106, RT014, and RT020. RT027 was more often associated with CDI-attributable death than was non-RT027, regardless of acquisition type. Overall resistance C. difficile rates were similar for all drugs tested except moxifloxacin. Adult HA and CA CDI rates have declined, coinciding with changes in prevalence of RT027 and RT106. Infection prevention and control and continued national surveillance are integral to clarifying CDI epidemiology, investigation, and control. 相似文献
85.
Zhang Y Li XL Lai WP Chen B Chow HK Wu CF Wang NL Yao XS Wong MS 《Journal of ethnopharmacology》2007,109(1):165-169
The present study was designed to investigate whether Erythrina variegata L. (EV), which belongs to the leguminous family, exerted any beneficial effects on bone in ovariectomized rats. Daily oral administration of the EV extract at 300 and 600 mg/kg for 14 weeks to rats prevented the OVX-induced increase in the serum OCN, ALP, and urinary DPD levels. Histomorphometric analysis of the proximal end of the tibia showed that the EV extract prevented the estrogen deficiency-induced decrease in trabecular thickness and trabecular area, as well as restoring the increase in trabecular separation in a dose-dependent manner. Moreover, the EV extract improved the energy absorption and stiffness of the mid-shaft of the rat femur. Thus, the present study clearly demonstrated that EV could suppress the high rate of bone turnover induced by estrogen deficiency, inhibit bone loss and improve the biomechanical properties of bone in the OVX rats. 相似文献
86.
AIMS: To compare the recurrence rates after anterior colporrhaphy for cystocele using three different surgical techniques: standard plicating, purse-string, and rolling anterior colporrhaphy. METHODS: A retrospective chart review of women undergoing anterior colporrhaphy for cystocele with or without concomitant operations between 1988 and 2000 was conducted. Women were assessed by vaginal examination pre- and postoperatively at 6 weeks and over 2 years. Grades of cystocele were assessed by Baden-Walker halfway grading system. chi(2) tests and ANOVAs were performed for categorical and continuous variables, respectively. Cox regressions were used to calculate recurrent rates. RESULTS: Among the studied 363 women, 296, 33, and 34 underwent standard plicating, purse-string and rolling techniques, respectively. There was no significant difference in age, parity, menopausal status, or mean length of follow-up among the three groups. The purse-string group revealed a significantly higher risk of recurrence than the standard plicating group (hazard ratio: 2.67; 95% CI: 1.05-6.08). The severity of cystocele was another key role of determining the prognosis for recurrences (grades 3 & 4 relative to grade 1, hazard ratio: 3.35; 95% CI: 1.34-8.38). CONCLUSION: Our study showed that standard plicating and rolling technique provided similar anatomic cure rates. However, the purse-string technique was less effective in restoring vaginal anatomy than standard plicating anterior colporrhaphy. 相似文献
87.
protection by vitamin E against endothelial cell injury by linoleic acid hydroperoxides 总被引:1,自引:0,他引:1
Exposure to 90 μM albumin-bound linoleic acid (18:2) for 24 hours significantly increased the rate of albumin transfer across cultured endothelial monolayers. Linoleic acid hydroperoxides (18:2-OOH) further accelerated the rate of albumin transfer over that of 18:2. Cells exposed to 18:2-OOH but not 18:2 caused a marked release of lactate dehydrogenase (LDH) into the media. Prior cellular incubation with media containing 25 μM vitamin E for 24 hours protected endothelial cells from injury by 18:2 and 18:2-OOH, as evidenced by a decreased rate of albumin transfer across the endothelium as well as reduced release of LDH into the media. These results suggest that vitamin E may provide protection against endothelial cell injury resulting from expusure to fatty acid hydroperoxides 相似文献
88.
89.
The cathepsin B inhibitor, benzyloxycarbonyl-phenylalanine-alanine-chloromethylketone (z-FA-CMK) was found to be toxic and readily induced cell death in the human T cell line, Jurkat, whereas two other analogs benzyloxycarbonyl-phenylalanine-alanine-fluoromethylketone (z-FA-FMK) and benzyloxycarbonyl-phenylalanine-alanine-diazomethylketone (z-FA-DMK) were not toxic. The toxicity of z-FA-CMK requires not only the CMK group, but also the presence of alanine in the P1 position and the benzyloxycarbonyl group at the N-terminal. Dose–response studies showed that lower concentrations of z-FA-CMK induced apoptosis in Jurkat T cells whereas higher concentrations induced necrosis. In z-FA-CMK-induced apoptosis, both initiator caspases (-8 and -9) and effector caspases (-3, -6 and -7) were processed to their respective subunits in Jurkat T cells. However, only the pro-form of the initiator caspases were reduced in z-FA-CMK-induced necrosis and no respective subunits were apparent. The caspase inihibitor benzyloxycarbonyl-valine-alanine-aspartic acid-(O-methyl)-fluoromehylketone (z-VAD-FMK) inhibits apoptosis and caspase processing in Jurkat T cells treated with low concentration of z-FA-CMK but has no effect on z-FA-CMK-induced necrosis and the loss of initiator caspases. This suggests that the loss of initiator caspases in Jurkat T cells during z-FA-CMK-induced necrosis is not a caspase-dependent process. Taken together, we have demonstrated that z-FA-CMK is toxic to Jurkat T cells and induces apoptosis at low concentrations, while at higher concentrations the cells die of necrosis. 相似文献
90.
Wing Shan Chow Winson Ka‐Lun Chan King Ming Chan 《Journal of applied toxicology : JAT》2013,33(7):670-678
Organochlorine pesticides and brominated flame retardants, such as tetrabromobisphenol A and polybrominated diphenyl ethers, pose an environmental hazard owing to their persistence, low solubility and estrogenic effects, and concerns have been raised regarding their effects on aquatic biota. In the present study, zebrafish embryos and larvae were used as a model to investigate the sublethal and lethal effects of three different organochlorine pesticides, namely methoxychlor, endosulfan and heptachlor, as well as the flame retardant tetrabromobisphenol A, and its precursor compound bisphenol A. Preliminary data for chemical exposure tests were obtained by determining the 96 h median effective concentration EC50 (hatching rate) and 96 h median lethal concentration LC50. Quantitative polymerase chain reaction was used to investigate the gene expression levels of the biomarker vitellogenin (vtg1) after 96 h exposures to 10, 25, 50 and 75% of the 96 h EC50 value for embryos and 96 h LC50 value for larvae. The use of vtg1 mRNA induction in zebrafish embryos and larvae was found to be a sensitive biomarker of exposure to these organic compounds, and was helpful in elucidating their adverse effects and setting water quality guidelines. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献