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991.
Fiona E Shaw John Bond David A Richardson Pamela Dawson I Nicholas Steen Ian G McKeith Rose Anne Kenny 《BMJ (Clinical research ed.)》2003,326(7380):73
ObjectiveTo determine the effectiveness of multifactorial intervention after a fall in older patients with cognitive impairment and dementia attending the accident and emergency department.DesignRandomised controlled trial.Participants274 cognitively impaired older people (aged 65 or over) presenting to the accident and emergency department after a fall: 130 were randomised to assessment and intervention and 144 were randomised to assessment followed by conventional care (control group).SettingTwo accident and emergency departments, Newcastle upon Tyne.ResultsIntention to treat analysis showed no significant difference between intervention and control groups in proportion of patients who fell during 1 year''s follow up (74% (96/130) and 80% (115/144), relative risk ratio 0.92, 95% confidence interval 0.81 to 1.05). No significant differences were found between groups for secondary outcome measures.ConclusionsMultifactorial intervention was not effective in preventing falls in older people with cognitive impairment and dementia presenting to the accident and emergency department after a fall.
What is already known on this topic
Multifactorial intervention prevents falls in cognitively normal older people living in the community and in those who present to the accident and emergency department after a fallFall prevention strategies have not been tested by controlled trials in patients with cognitive impairment and dementia who fallWhat this study adds
No benefit was shown from multifactorial assessment and intervention after a fall in patients with cognitive impairment and dementia presenting to the accident and emergency departmentThe intervention was less effective in these patients than in cognitively normal older people 相似文献992.
THE NORTH ISLAND HECTOR'S DOLPHIN IS VULNERABLE TO EXTINCTION 总被引:1,自引:1,他引:0
Stephen Dawson Franz Pichler Elisabeth Slooten Kirsty Russell C. Scott Baker 《Marine Mammal Science》2001,17(2):366-371
993.
The Arabidopsis MALE STERILITY1 (MS1) gene is a transcriptional regulator of male gametogenesis, with homology to the PHD-finger family of transcription factors 总被引:25,自引:0,他引:25
994.
U.K. Pun J.S. Rowarth M.F. Barnes J.A. Heyes R.N. Rowe C.O. Dawson 《Plant Growth Regulation》2001,34(3):267-272
The effects of acetaldehyde concentration (0, 0.025, 0.05, 0.1, 0.2,0.3, 0.4 or 0.5%) in solution on the vase life and ethylene productionoftwo carnation (Dianthus caryophyllus L.) cultivarscontrasting in vase life (Sandrosa (long lasting) and Yellow Candy (shortlasting)) were studied. In Sandrosa, acetaldehyde solution (0.05%)increased the vase life by 3 days in the absence, or by 2 days in the presence,of exogenous ethylene; the increase in vase life was associated with a delay inthe ethylene climacteric peak. In Yellow Candy, acetaldehyde (0.05%)increased vase life by 3 days, in an ethylene free environment. In the presenceof exogenous ethylene there was no increase in vase life of Yellow Candy.Acetaldehyde failed to inhibit ethylene production in either of the cultivars.It is suggested that acetaldehyde is not involved in the inhibition of ethylenebiosynthesis or sensitivity to ethylene in these two carnation cultivars. 相似文献
995.
996.
Parasites have the potential to decrease reproductive output of hosts by competing for nutrients or forcing hosts to invest in immune function. Conversely, reproductive output may affect parasite loads if hosts allocate resources to reproduction such that allocation to immune function is compromised. Both hypotheses implicitly have a temporal component, so we sampled parasites both before and after egg laying to examine the relationship between reproductive output (indexed using a combined measure of clutch size, egg volume, and initiation date) and blood parasite loads of American kestrels (Falco sparverius). Parasite loads measured prior to egg laying had no adverse effects on subsequent reproductive output. Females that previously had large reproductive outputs subsequently had lower parasite intensities than those whose outputs were smaller, suggesting that females were capable of allocating energy to both forming clutches and reducing parasite loads. Because male kestrels provide most of their mate's energetic needs before, during, and after egg laying, mate choice by females may have consequences for their parasite loads. Females choosing high-quality mates may not only have increased reproductive output, but may also obtain sufficient resources from their mates to enable them to reduce their parasite burdens. Males whose mates had large reproductive outputs were more likely to subsequently be parasitized and have more intense infections. For individual males sampled both before and after egg laying, those whose mates had larger reproductive outputs were also more likely to become parasitized, or remain parasitized, between sampling periods. Increased parasite loads of males may be one mechanism by which the costs of reproduction are paid. 相似文献
997.
We investigated the effect of competition from grass roots (as controlled by herbicide application) on the depth distribution of white roots in cherry trees, grown with varying rates and frequency of application of N in an agroforestry system. Statistical summaries of distribution, namely mean and skewness, produced a concise and interpretable analysis of the data.There was a large increase in tree root numbers in the surface horizons after the herbicide had reduced grass root competition. Where the surrounding grass had not been reduced by herbicide, the average depth of tree roots increased with time, contrasting with a marked shift in the mode of distribution of root numbers to shallow depths when grass competition was removed. These findings are important in the understanding of plant root competition and for prescribing best practise for tree establishment in agroforestry systems. 相似文献
998.
Diversity and Specificity of Frankia Strains in Nodules of Sympatric Myrica gale, Alnus incana, and Shepherdia canadensis Determined by rrs Gene Polymorphism 总被引:3,自引:0,他引:3 下载免费PDF全文
Valerie Huguet Janet Mccray Batzli Jeff F. Zimpfer Philippe Normand Jeffrey O. Dawson Maria P. Fernandez 《Applied microbiology》2001,67(5):2116-2122
The identity of Frankia strains from nodules of Myrica gale, Alnus incana subsp. rugosa, and Shepherdia canadensis was determined for a natural stand on a lake shore sand dune in Wisconsin, where the three actinorhizal plant species were growing in close proximity, and from two additional stands with M. gale as the sole actinorhizal component. Unisolated strains were compared by their 16S ribosomal DNA (rDNA) restriction patterns using a direct PCR amplification protocol on nodules. Phylogenetic relationships among nodular Frankia strains were analyzed by comparing complete 16S rDNA sequences of study and reference strains. Where the three actinorhizal species occurred together, each host species was nodulated by a different phylogenetic group of Frankia strains. M. gale strains from all three sites belonged to an Alnus-Casuarina group, closely related to Frankia alni representative strains, and were low in diversity for a host genus considered promiscuous with respect to Frankia microsymbiont genotype. Frankia strains from A. incana nodules were also within the Alnus-Casuarina cluster, distinct from Frankia strains of M. gale nodules at the mixed actinorhizal site but not from Frankia strains from two M. gale nodules at a second site in Wisconsin. Frankia strains from nodules of S. canadensis belonged to a divergent subset of a cluster of Elaeagnaceae-infective strains and exhibited a high degree of diversity. The three closely related local Frankia populations in Myrica nodules could be distinguished from one another using our approach. In addition to geographic separation and host selectivity for Frankia microsymbionts, edaphic factors such as soil moisture and organic matter content, which varied among locales, may account for differences in Frankia populations found in Myrica nodules. 相似文献
999.
Transgene-mediated and elicitor-induced perturbation of metabolic channeling at the entry point into the phenylpropanoid pathway 总被引:12,自引:0,他引:12 下载免费PDF全文
3H-l-Phenylalanine is incorporated into a range of phenylpropanoid compounds when fed to tobacco cell cultures. A significant proportion of (3)H-trans-cinnamic acid formed from (3)H-l-phenylalanine did not equilibrate with exogenous trans-cinnamic acid and therefore may be rapidly channeled through the cinnamate 4-hydroxylase (C4H) reaction to 4-coumaric acid. Such compartmentalization of trans-cinnamic acid was not observed after elicitation or in cell cultures constitutively expressing a bean phenylalanine ammonia-lyase (PAL) transgene. Channeling between PAL and C4H was confirmed in vitro in isolated microsomes from tobacco stems or cell suspension cultures. This channeling was strongly reduced in microsomes from stems or cell cultures of transgenic PAL-overexpressing plants or after elicitation of wild-type cell cultures. Protein gel blot analysis showed that tobacco PAL1 and bean PAL were localized in both soluble and microsomal fractions, whereas tobacco PAL2 was found only in the soluble fraction. We propose that metabolic channeling of trans-cinnamic acid requires the close association of specific forms of PAL with C4H on microsomal membranes. 相似文献
1000.
Jennifer E. Dawson Iris Nira Smith William Martin Krishnendu Khan Feixiong Cheng Charis Eng 《Protein science : a publication of the Protein Society》2022,31(5)
The Phosphatase and TENsin homolog deleted on chromosome 10 (PTEN) is a chief regulator of a variety of cellular processes including cell proliferation, migration, growth, and death. It is also a major tumor suppressor gene that is frequently mutated or lost under cancerous conditions. PTEN encodes a dual‐specificity (lipid and protein) phosphatase that negatively regulates the PI3K/AKT/mTOR signaling pathway where the PIP2‐binding domain (PBD) regulates the lipid phosphatase function. Unfortunately, despite two decades of research, a full‐length structure of PTEN remains elusive, leaving open questions regarding PTEN''s disordered regions that mediate protein stability, post‐translational modifications, protein–protein interactions, while also hindering the design of small molecules that can regulate PTEN''s function. Here, we utilized a combination of crosslinking mass spectrometry, in silico predicted structural modeling (including AlphaFold2), molecular docking, molecular dynamics simulations, and residue interaction network modeling to obtain structural details and molecular insight into the behavior of the PBD of PTEN. Our study shows that the PBD exists in multiple conformations which suggests its ability to regulate PTEN''s variety of functions. Studying how these specific conformational substates contribute to PTEN function is imperative to defining its function in disease pathogenesis, and to delineate ways to modulate its tumor suppressor activity. 相似文献