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排序方式: 共有643条查询结果,搜索用时 31 毫秒
1.
MMPs及其调控因子与滋养层细胞的侵袭 总被引:5,自引:2,他引:5
滋养层细胞的侵袭行为受严格的时空调控 ,细胞外基质降解是滋养层细胞侵袭过程的关键步骤 ,也是成功妊娠建立的必要条件。基质金属蛋白酶 ( MMPs)是参与细胞外基质降解的关键酶 ,因此也是滋养层细胞侵袭行为调控的关键因子 ,滋养层细胞的自分泌和子宫的旁分泌因子如 :激素、细胞因子、生长因子、基质蛋白等可调节 MMPs活性 ,进而参与滋养层细胞侵袭过程 相似文献
2.
This follow-up study was undertaken in an effort to ascertain the morbidity in the survivors of infants ≤2000 g birthweight cared for in the two Rockhampton intensive care nurseries.
The records of all infants ≤2000 g delivered in or transferred to Rockhampton during the 11 year period 1979 through 1989 inclusive were extracted. Efforts were made to contact and examine all of these children. Those found to be disabled were assessed as being mildly, moderately or severely affected.
Of the 482 infants of birthweight ≤2000 g treated in the period under review, 393 survived to be discharged from hospital. Eight were known to have died subsequently. Of the remaining 385 children, 288 (74.8%) were able to be contacted and their health status determined. A total of 36 infants were found to have significant disabilities. Twenty-four were mildly affected, five moderately and seven severely affected. Severe disability in infants of ≤1000 g was 16% (3/19).
The incidence of disability was established in 74.8% of the surviving population, It was not dissimilar to the incidence of disability in similar birthweight groups in some Australian tertiary centres for the years under study. It is emphasized that the follow-up was incomplete and recognized that the survival rates and incidence of disability in survivors has improved in tertiary centres since the time frame of this study. 相似文献
Methodology:
The records of all infants ≤2000 g delivered in or transferred to Rockhampton during the 11 year period 1979 through 1989 inclusive were extracted. Efforts were made to contact and examine all of these children. Those found to be disabled were assessed as being mildly, moderately or severely affected.
Results:
Of the 482 infants of birthweight ≤2000 g treated in the period under review, 393 survived to be discharged from hospital. Eight were known to have died subsequently. Of the remaining 385 children, 288 (74.8%) were able to be contacted and their health status determined. A total of 36 infants were found to have significant disabilities. Twenty-four were mildly affected, five moderately and seven severely affected. Severe disability in infants of ≤1000 g was 16% (3/19).
Conclusions:
The incidence of disability was established in 74.8% of the surviving population, It was not dissimilar to the incidence of disability in similar birthweight groups in some Australian tertiary centres for the years under study. It is emphasized that the follow-up was incomplete and recognized that the survival rates and incidence of disability in survivors has improved in tertiary centres since the time frame of this study. 相似文献
3.
杭白菊开花习性及花期调控研究 总被引:6,自引:0,他引:6
以杭白菊的两个栽培类型大白菊和小白菊为试验材料,从形态特征及生长发育习性等方面进行比较,并进行了植物生长调节剂对杭白菊的开花习性及产量和品质影响试验。发现两个栽培类型在花的大小及产量方面差异显著,赤霉素可提早开花,减轻低温对花质量的影响 相似文献
4.
5.
The endothelial layer represents a continuous physical barrier that controls coagulation and allows selective passage of soluble molecules and circulating cells across the vessel wall into the tissue. The functional activity of the endothelial cells may be influenced by their interaction with components of the complement system. In this review we shall discuss the complex interplay that can be established between the endothelium and complement proteins or activation products. Endothelial cells may also secrete several complement components which contribute to the circulating pool. This process can be regulated by cytokines and other pro-inflammatory stimuli. In addition, complement activation products stimulate endothelial cells to acquire a pro-inflammatory and pro-coagulant status. Expression of regulatory molecules on the cell surface provides protection against an undesired attack by complement activation products. Unrestricted complement activation under pathological conditions may lead to structural and functional changes of the endothelium resulting in vascular disease. 相似文献
6.
目的 加强人才队伍建设,推动科学检验工作。方法 分析省级食品药品检验机构人才队伍的现状,介绍陕西省食品药品检验所通过选才、育才、聚才等一系列举措,加强人才队伍建设的具体实践。结果与结论 通过加快推进事业单位人事制度改革,进一步健全培养机制,强化培养措施,为科学检验提供有力的人才支撑。 相似文献
7.
8.
《Autoimmunity》2013,46(1):64-75
The actin cytoskeleton plays a crucial role in a variety of important cellular processes required for normal immune function, including locomotion, intercellular interactions, endocytosis, cytokinesis, signal transduction, and maintenance of cell morphology. Recent studies have uncovered not only many of the components and mechanisms that regulate the cortical actin cytoskeleton but have also revealed significant immunopathological consequences associated with genetic alteration of actin cytoskeletal regulatory genes. These advances have provided new insights into the role of cortical actin cytoskeletal regulation in a number of immune cell functions and have identified cytoskeletal regulatory proteins critical for normal immune system activity and susceptibility to autoimmunity. 相似文献
9.
背景:骨不连是骨折晚期常见的临床问题,数十年来,在各种新式内外固定材料、普及的显微外科技术、创新的植骨材料,尤其是分子生物学技术的全面帮助下,骨不连的治疗取得了突破性进展。
目的:总结骨不连治疗的研究进展,为以后更好地治疗骨不连提供技术理论和方法选择。
方法:由第一作者运用计算机检索系统检索1990年1月至2013年5月发表的有关骨不连原因及治疗方法的文献,以“fracture nonunion,treatment,progress”或“骨不连,治疗方法,进展”为检索词。同一领域则选择近期发表或者发表在权威杂志的文章。
结果与结论:排除重复性研究及时间跨度大的文献,从检索结果中共选择了48篇文章进一步分析。骨不连治疗手段主要有两种:非手术方式和手术方式,目前临床上以手术方式为主且高效。骨折愈合是多环节参与的复杂过程,一旦骨不连发生,应具体问题具体分析,根据患者的实际情况采取个体化治疗原则,重视软组织的保护,必要时联合运用多种手术及非手术方法,才能取得满意的疗效。 相似文献
目的:总结骨不连治疗的研究进展,为以后更好地治疗骨不连提供技术理论和方法选择。
方法:由第一作者运用计算机检索系统检索1990年1月至2013年5月发表的有关骨不连原因及治疗方法的文献,以“fracture nonunion,treatment,progress”或“骨不连,治疗方法,进展”为检索词。同一领域则选择近期发表或者发表在权威杂志的文章。
结果与结论:排除重复性研究及时间跨度大的文献,从检索结果中共选择了48篇文章进一步分析。骨不连治疗手段主要有两种:非手术方式和手术方式,目前临床上以手术方式为主且高效。骨折愈合是多环节参与的复杂过程,一旦骨不连发生,应具体问题具体分析,根据患者的实际情况采取个体化治疗原则,重视软组织的保护,必要时联合运用多种手术及非手术方法,才能取得满意的疗效。 相似文献
10.
Background:Osteosarcoma represents the most common malignant bone tumor with high metastatic potential and inferior prognosis. RNA methylation (N6-methyladenosine [m6A]) is a prevalent RNA modification that epigenetically influences numerous biological processes including tumorigenesis. This study aims to determine that m6A regulators are significant biomarkers for osteosarcoma, and establish a prognostic model to predict the survival of patients.Methods:In this study, we comprehensively analyzed the underlying associations between m6A regulators’ mRNA expressions and metastasis as well as prognosis of osteosarcoma patients in the Cancer Genome Atlas. Multivariate Cox-regression analysis was used to screen regulators that were significantly associated with overall survival of osteosarcoma patients. Least absolute shrinkage and selection operator (LASSO) Cox-regression analysis was used for constructing m6A regulator-based osteosarcoma prognostic signature.Results:Some of the regulators exhibited aberrant mRNA levels between osteosarcoma samples with and without metastasis. Multivariate Cox-regression analysis identified several regulators with potential prognostic significance. A risk score formula consisted of methyltransferase-like 3, YTH domains of Homo sapiens, and fat mass and obesity-associated protein was obtained through which patients could be prognostically stratified independently of potential confounding factors. The signature was also significantly associated with the metastatic potential of osteosarcoma. All the analyses could be well reproduced in another independent osteosarcoma cohort from the Gene Expression Omnibus.Conclusions:In conclusion, this study first revealed potential roles of m6A regulators in osteosarcoma metastasis and prognosis, which should be helpful for its clinical decision-making. 相似文献