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51.
人工关节置换术是矫正关节畸形、解除关节疼痛、重建关节功能的主要手段。多年来 ,人工全髋、全膝皆以聚乙烯为关节形成表面 ,随着人工关节置换的广泛开展 ,聚乙烯磨损问题越来越引起人们的关注。聚乙烯磨损及其产生的碎屑和磨损颗粒所引发的生物学反应及导致的骨吸收、骨溶解 ,是造成假体松动、人工关节翻修的主要原因[1,2 ] 。与人工髋关节的球洞几何形态相比 ,人工膝关节的几何形态要不吻合的多 ,胫骨假体表面常承受较大的接触应力 ,较易产生磨损[2 ,3 ] ,理论上关节形成表面越吻合 ,聚乙烯磨损越少 ,不同的胫股关节吻合性 ,对假体磨损产… 相似文献
52.
Ingunn M. Stefansson Maria Raeder Elisabeth Wik Monica Mannelqvist Kanthida Kusonmano G?ril Knutsvik Ingfrid Haldorsen Jone Trovik Anne M. ?yan Karl-H. Kalland Anne Cathrine Staff Helga B. Salvesen Lars A. Akslen 《Oncotarget》2015,6(12):10634-10645
Background
Angiogenesis is a hallmark of cancer. The aim of this study was to explore whether microvessel proliferation is associated with gene expression profiles or copy number alterations in endometrial cancer.Methods
A prospective series of endometrial carcinomas was studied for angiogenesis markers, gene expression profiles, and gene copy number data. For validation, an independent series of endometrial carcinomas as well as an external cohort of endometrial cancer patients were examined by gene expression microarrays.Results
Increased microvessel proliferation (MVP) was associated with aggressive tumor features and reduced survival, and a 32-gene expression signature was found to separate tumors with high versus low MVP. An increased 32-gene signature score was confirmed to associate with high-grade tumor features and reduced survival by independent cohorts. Copy number studies revealed that amplification of the 6p21 region was significantly associated with MVP, a high 32-gene score, as well as reduced survival.Conclusion
Increased MVP was significantly associated with aggressive endometrial cancer and reduced survival. Integrated analyses demonstrated significant associations between increased vascular proliferation, amplification of the 6p21 region, VEGF-A mRNA expression, and the 32-gene angiogenesis signature. Our findings indicate amplification of 6p21 as a possible driver of tumor vascular proliferation in endometrial cancer. 相似文献53.
54.
Nicolay Stien Helene Pedersen Vegard A. Vereide Atle H. Saeterbakken Espen Hermans Jarle Kalland Brad J. Schoenfeld Vidar Andersen 《Journal of Sports Science and Medicine》2021,20(3):438
This study examined the effects of two or four weekly campus board training sessions among highly accomplished lead climbers. Sixteen advanced-to-elite climbers were randomly allocated to two (TG2), or four weekly campus board training sessions (TG4), or a control group (CG). All groups continued their normal climbing routines. Pre- and post-intervention measures included bouldering performance, maximal isometric pull-up strength using a shallow rung and a large hold (jug), and maximal reach and moves to failure. Rate of force development (RFD; absolute and 100ms) was calculated in the rung condition. TG4 improved maximal force in the jug condition (effect size (ES) = 0.40, p = 0.043), and absolute RFD more than CG (ES = 2.92, p = 0.025), whereas TG2 improved bouldering performance (ES = 2.59, p = 0.016) and maximal moves to failure on the campus board more than CG (ES = 1.65, p = 0.008). No differences between the training groups were found (p = 0.107–1.000). When merging the training groups, the training improved strength in the rung condition (ES = 0.87, p = 0.002), bouldering performance (ES = 2.37, p = 0.006), maximal reach (ES = 1.66, p = 0.006) and moves to failure (ES = 1.43, p = 0.040) more than CG. In conclusion, a five-week campus board training-block is sufficient for improving climbing-specific attributes among advanced-to-elite climbers. Sessions should be divided over four days to improve RFD or divided over two days to improve bouldering performance, compared to regular climbing training.Key points
- Five weeks of volume equated campus board training may similarly improve finger strength, maximal reach and number of campus moves to failure regardless of training frequency.
- Four weekly sessions may be more effective than two weekly sessions for improving rate of force development in an isometric pull-up using a climbing-specific hold
- Two weekly sessions could be more effective than four weekly sessions for improving bouldering performance when volume is equated.
55.
Mauland KK Trovik J Wik E Raeder MB Njølstad TS Stefansson IM Oyan AM Kalland KH Bjørge T Akslen LA Salvesen HB 《British journal of cancer》2011,104(6):921-926
Background:
Endometrial cancer incidence is increasing in industrialised countries. High body mass index (BMI, kg m−2) is associated with higher risk for disease. We wanted to investigate if BMI is related to clinico-pathological characteristics, hormone receptor status in primary tumour, and disease outcome in endometrial cancer.Patients and methods:
In total, 1129 women primarily treated for endometrial carcinoma at Haukeland University Hospital during 1981–2009 were studied. Body mass index was available for 949 patients and related to comprehensive clinical and histopathological data, hormone receptor status in tumour, treatment, and follow-up.Results:
High BMI was significantly associated with low International Federation of Gynaecology and Obstetrics (FIGO) stage, endometrioid histology, low/intermediate grade, and high level of progesterone receptor (PR) mRNA by qPCR (n=150; P=0.02) and protein expression by immunohistochemistry (n=433; P=0.003). In contrast, oestrogen receptor (ERα) status was not associated with BMI. Overweight/obese women had significantly better disease-specific survival (DSS) than normal/underweight women in univariate analysis (P=0.035). In multivariate analysis of DSS adjusting for age, FIGO stage, histological subtype, and grade, BMI showed no independent prognostic impact.Conclusion:
High BMI was significantly associated with markers of non-aggressive disease and positive PR status in a large population-based study of endometrial carcinoma. Women with high BMI had significantly better prognosis in univariate analysis of DSS, an effect that disappeared in multivariate analysis adjusting for established prognostic markers. The role of PR in endometrial carcinogenesis needs to be further studied. 相似文献56.
KH Nyqvist GC Anderson N Bergman A Cattaneo N Charpak R Davanzo U Ewald S Ludington‐Hoe S Mendoza C Pallás‐Allonso JG Peláez J Sizun A‐M Widström 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(6):812-819
Since Kangaroo Mother Care (KMC) was developed in Colombia in the 1970s, two trends in clinical application emerged. In low income settings, the original KMC model is implemented. This consists of continuous (24 h/day, 7 days/week) and prolonged mother/parent–infant skin‐to‐skin contact; early discharge with the infant in the kangaroo position; (ideally) exclusive breastfeeding; and, adequate follow‐up. In affluent settings, intermittent KMC with sessions of one or a few hours skin‐to‐skin contact for a limited period is common. As a result of the increasing evidence of the benefits of KMC for both infants and families in all intensive care settings, KMC in a high‐tech environment was chosen as the topic for the first European Conference on KMC, and the clinical implementation of the KMC model in all types of settings was discussed at the 7th International Workshop on KMC. Kangaroo Mother Care protocols in high‐tech Neonatal Intensive Care Units (NICU) should specify criteria for initiation, kangaroo position, transfer to/from KMC, transport in kangaroo position, kangaroo nutrition, parents’ role, modification of the NICU environment, performance of care in KMC, and KMC in case of infant instability. Conclusion: Implementation of the original KMC method, with continuous skin‐to‐skin contact whenever possible, is recommended for application in high‐tech environments, although scientific evaluation should continue. 相似文献
57.
58.
RM Bologa DM Levine TS Parker JS Cheigh D Serur KH Stenzel AL Rubin 《American journal of kidney diseases》1998,32(1):107-114
Low serum albumin and low serum cholesterol levels are among the most consistent predictors of mortality in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Hypoalbuminemia is often interpreted as a marker of poor nutrition, but serum albumin and cholesterol levels can also be low as part of a cytokine-mediated acute-phase reaction to acute or chronic inflammation. Here we report the results from a 900-day prospective study designed to determine whether tumor necrosis factor-alfa (TNF-alpha) and interleukin-6 (IL-6) predict serum albumin and cholesterol levels and mortality in a group of 90 ambulatory, adult hemodialysis patients with no acute infection, hospitalization or surgery, and no known acquired immunodeficiency syndrome (AIDS), malignancy, or liver disease. Measurable levels of TNF-alpha and/or IL-6 were found in 89 of 90 patients. Significant relationships were found between TNF-alpha and IL-6 and the degree of hypoalbuminemia and dyslipoproteinemia. IL-6 was the strongest predictor of mortality in univariate and multivariate analysis, followed by age, albumin level, and body mass index (BMI). Although the cause of hypercytokinemia was not addressed in this study, the data support the view that hypoalbuminemia and hypocholesterolemia are negative acute-phase responses to inflammatory stimuli. These results suggest that efforts to identify the nature of the stimuli for cytokine production and to lower cytokine levels in hemodialysis patients might be effective in improving the survival of patients undergoing hemodialysis. 相似文献
59.
Robertson RT; Gallardo KA; Claytor KJ; Ha DH; Ku KH; Yu BP; Lauterborn JC; Wiley RG; Yu J; Gall CM; Leslie FM 《Cerebral cortex (New York, N.Y. : 1991)》1998,8(2):142-155
The role of basal forebrain-derived cholinergic afferents in the
development of neocortex was studied in postnatal rats. Newborn rat pups
received intraventricular injections of 192 IgG-saporin. Following survival
periods ranging from 2 days to 6 months, the brains were processed to
document the cholinergic lesion and to examine morphological consequences.
Immunocytochemistry for choline acetyltransferase (ChAT) and in situ
hybridization for ChAT mRNA demonstrate a loss of approximately 75% of the
cholinergic neurons in the medial septum and nucleus of the diagonal band
of Broca in the basal forebrain. In situ hybridization for glutamic acid
decarboxylase mRNA reveals no loss of basal forebrain GABAergic neurons.
Acetylcholinesterase histochemistry demonstrates a marked reduction of the
cholinergic axons in neocortex. Cholinergic axons are reduced throughout
the cortical layers; this reduction is more marked in medial than in
lateral cortical areas. The thickness of neocortex is reduced by
approximately 10%. Retrograde labeling of layer V cortico-collicular
pyramidal cells reveals a reduction in cell body size and also a reduction
in numbers of branches of apical dendrites. Spine densities on apical
dendrites are reduced by approximately 20-25% in 192 IgG- saporin-treated
cases; no change was detected in number of spines on basal dendrites. These
results indicate a developmental or maintenance role for cholinergic
afferents to cerebral cortical neurons.
相似文献
60.
Andrew KC Lam Ken KH Cheng Rex K Lam Christina FC Lau SY Yau 《Clinical & experimental optometry》1996,79(4):167-172
Myopic crescent, refractive error and axial length were previously investigated in Hong Kong Chinese subjects. The myopic crescent was found to correlate with axial length and myopic refraction. In this study, three groups of Hong Kong Chinese with different degrees of myopia were assessed for optic disc ovalness, refractive error and axial length. The axial length was significantly correlated with the degree of myopia, indicating that the myopia was axial in nature. The regression line shows that 0.44 mm of axial elongation would give about one dioptre of increase in myopia. The elliptical ratio of the optic disc was defined as the maximal disc diameter divided by the minimal disc diameter. All three groups showed an oval disc with vertical axis greater and an increased ovalness for the high myopic group with an elliptical ratio from 1.11 in low myopia to 1.29 in high myopia. There is a small amount (about four degrees) of temporal rotation of this vertical oval orientation, which is independent of the amount of myopia. This result shows an association between axial elongation of the globe and optic disc ovalness, in addition to the previously described temporal myopic crescent. Therefore, in myopic subjects, a vertically oval disc may be associated with a myopic refraction rather than glaucoma. 相似文献