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排序方式: 共有606条查询结果,搜索用时 15 毫秒
91.
Van Dyck P Vanhoenacker FM Gielen JL Dossche L Van Gestel J Wouters K Parizel PM 《Skeletal radiology》2011,40(6):701-707
Purpose
To determine the ability of 3.0T magnetic resonance (MR) imaging to identify partial tears of the anterior cruciate ligament (ACL) and to allow distinction of complete from partial ACL tears. 相似文献92.
93.
Vascular endothelial growth factor A (VEGF-A) stimulates angiogenesis, but is also pro-inflammatory and plays an important role in the development of neurological disease, where it can have both attenuating and exacerbating effects. VEGF-B, a related molecule, is highly expressed in the central nervous system and seems to be important in neurological injury. A few studies have indicated that VEGF-A may play a role in the pathogenesis of multiple sclerosis (MS), but the role of VEGF-B has not been studied. We have studied the expression of VEGF-A, -B and their receptors by mRNA in situ hybridization, immunohistochemistry and real-time PCR in spinal cord from LEW rats with experimental autoimmune encephalomyelitis (EAE) and in cerebrospinal fluid (CSF) and blood samples from MS patients. Whereas VEGF-A is downregulated in glia in EAE, the infiltrating inflammatory cells are positive for VEGF-A. Expression of VEGF-B and the VEGF receptors is unaltered. In addition, the levels of VEGF-A mRNA in mononuclear cells [corrected] in CSF are lower in MS patients compared with controls. These results demonstrate a complex regulation of VEGF-A during neuroinflammation and suggest that VEGF-B is not involved in the pathogenesis of MS. 相似文献
94.
Quicker onset and shorter elimination time favours (+/-) articaine as a short-acting local anaesthetic for regional anaesthesia in day-case settings, e.g. arthroscopy (shoulder, knee), hand and foot surgery, and dentistry, because patients treated with articaine will be 'drug free' more quickly than those who receive other local anaesthetics. Articaine diffuses better through soft tissue and bone than other local anaesthetics. The concentration of articaine in the alveolus of a tooth in the upper jaw after extraction was about 100 times higher than that in systemic circulation. Articaine is metabolised via hydrolysis into articainic acid, 75% of which in turn is excreted as such and 25% in the glucuronidated form by the kidneys. The half-lives of elimination (t1/2alpha and t1/2beta) of articaine are 0.6 and 2.5 hours, whereas the apparent half-life of the metabolite articainic acid is 2.5 hours. Intrinsic half-lives of articainic acid are: t1/2alpha 12 minutes, and t1/2beta 64 minutes (1 hour). In dentistry, articaine is the drug of choice in the vast majority of literature. In other regional anaesthesia techniques (intravenous regional anaesthesia, epidural, spinal and plexus blocks) there are not enough data to prove that (+/-) articaine is safer and more effective than the short-acting local anaesthetics lidocaine, (+/-) prilocaine or (+/-) mepivacaine. 相似文献
95.
Wendy C. Shields Elise C. Perry Sarah L. Szanton Margaret R. Andrews Rebecca L. Stepnitz Eileen M. McDonald Andrea C. Gielen 《Geriatric nursing (New York, N.Y.)》2013
This study aimed to describe the prevalence of preventive safety measures in homes with older, urban-dwelling adults; determine the relationship between sociodemographic variables and injury prevention measures; and describe older adults’ knowledge of safety topics. Teams conducted interviews and home observations in 603 homes to confirm preventive safety measures. Households with older adults were rarely observed to have recommended smoke alarm (34%) or carbon monoxide coverage (22%). Water temperature was safe in 64% of homes. Among households headed by someone other than the older adult, odds of having a working smoke alarm on every floor were much lower than in older adult–headed households (95% confidence interval: 0.04-0.35). Few older adults interviewed about safety knowledge correctly answered several items related to fire and carbon monoxide. Effort is needed to improve knowledge and promote the lifesaving benefits of injury countermeasures so that older adults can be adequately protected. 相似文献
96.
Dreesen J Drüsedau M Smeets H de Die-Smulders C Coonen E Dumoulin J Gielen M Evers J Herbergs J Geraedts J 《Molecular human reproduction》2008,14(10):573-579
The aim of this study was to validate the overall preimplantation genetic diagnosis (PGD)-PCR procedure and to determine the diagnostic value. Genotyped embryos not selected for embryo transfer (ET) and unsuitable for cryopreservation after PGD were used for confirmatory analysis. The PGD genotyped blastomeres and corresponding embryos were compared, and morphology was scored on Day 4 post fertilization. To establish the validity of the PGD-PCR procedure and the diagnostic value, misdiagnosis rate, false-negative rate and negative predictive value were calculated. Moreover, comparison on the validity was made for the biopsy of one or two blastomeres. For the total embryo group (n = 422), a misdiagnosis rate of 7.1% and a false-negative rate of 3.1% were found. The negative predictive value was 96.1%. Poor morphology Day 4 embryos (Class 1) were over-represented in the embryo group in which the blastomere genotype was not confirmed by the whole embryo genotype. The misdiagnosis rate of Class 1 embryos was 12.5% and the false-negative rate 17.1%. Exclusion of these embryos resulted in a misdiagnosis rate of 6.1%, a false-negative rate of 0.5% and a negative predictive value of 99.3%. The two blastomere biopsies revealed a significant higher positive predictive value, lowering the misdiagnosis rate, whereas the negative predictive value remained the same. In conclusion, the PGD-PCR procedure is a valid diagnostic method to select unaffected embryos for ET. The misdiagnosis and false-negative rates decrease by rejecting Class 1 embryos for ET. The biopsy of a second blastomere improves the positive predictive value, lowering the misdiagnosis rate. 相似文献
97.
BACKGROUND: Numerous studies have demonstrated an association between characteristics of the school environment and the likelihood of school violence. However, little is known about the relative importance of various characteristics of the school environment or their differential impact on multiple violence outcomes. METHODS: Primarily African‐American students (n = 27) from Baltimore City high schools participated in concept mapping sessions, which produced interpretable maps of the school environment's contribution to school violence. Participants generated statements about their school environment's influence on school violence and, with the assistance of quantitative methods, grouped these statements according to their similarity. Participants provided information about the importance of each of these statements for the initiation, cessation, and severity of the violence that occurs at school. RESULTS: More than half of the 132 statements generated by students were rated as school environment characteristics highly important for the initiation, cessation, and/or severity of school violence. Participants identified students' own actions, expectations for disruptive behavior, and the environment outside the school as the characteristics most important for the initiation and increased severity of violence that occurs in school. Participants had a more difficult time identifying school environment characteristics important for the cessation of school violence. CONCLUSION: This study provides support from students for the role of the school environment in school violence prevention, particularly in preventing the initiation and reducing the severity of school violence. Schools can utilize the information presented in this article to begin discussions with students and staff about prioritizing school environment changes to reduce school violence. 相似文献
98.
Dieteren CE Gielen SC Nijtmans LG Smeitink JA Swarts HG Brock R Willems PH Koopman WJ 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(21):8657-8662
Intracellular chemical reactions generally constitute reaction-diffusion systems located inside nanostructured compartments like the cytosol, nucleus, endoplasmic reticulum, Golgi, and mitochondrion. Understanding the properties of such systems requires quantitative information about solute diffusion. Here we present a novel approach that allows determination of the solvent-dependent solute diffusion constant (D(solvent)) inside cell compartments with an experimentally quantifiable nanostructure. In essence, our method consists of the matching of synthetic fluorescence recovery after photobleaching (FRAP) curves, generated by a mathematical model with a realistic nanostructure, and experimental FRAP data. As a proof of principle, we assessed D(solvent) of a monomeric fluorescent protein (AcGFP1) and its tandem fusion (AcGFP1(2)) in the mitochondrial matrix of HEK293 cells. Our results demonstrate that diffusion of both proteins is substantially slowed by barriers in the mitochondrial matrix (cristae), suggesting that cells can control the dynamics of biochemical reactions in this compartment by modifying its nanostructure. 相似文献
99.
The Fostering African American Improvement in Total Health! (FAITH!) Nutrition Education Program is a theory-based, multicomponent health intervention developed and operated in partnership with an East Baltimore church. The program aims to improve eating habits, as well as knowledge and beliefs about healthy eating, among African American adults in order to prevent diseases related to dietary choices. This article addresses the development, design, and formative research that informed the FAITH! program. The main program components are also discussed. Program design used a framework for strategic intervention planning (PRECEDE-PROCEED), and health education theories informed the evaluation process. Formative research was conducted to incorporate the needs and assets of the priority population. The main program components are culturally tailored educational materials, lectures and discussions on diet and related diseases, video presentations on healthy eating, healthy cooking demonstrations/food samples, evaluation, and a church-run healthy food pantry. 相似文献
100.
Clemens?SeidelEmail authorView authors OrcID profile André?O.?von Bueren Sabrina?Bojko Marion?Hoffmann Torsten?Pietsch Gerrit?H.?Gielen Monika?Warmuth-Metz Brigitte?Bison Rolf?D.?Kortmann Christof?M.?Kramm 《Strahlentherapie und Onkologie》2018,194(3):215-224