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991.
Standards of care pertain to crafting and implementing patient-centered treatment interventions. Standards of care must take into consideration the patient's gender, ethnicity, medical and dental history, insurance coverage (or socioeconomic level, if a private patient), and the timeliness of the targeted scientific evidence. This resolves into a process by which clinical decision-making about the optimal patient-centered treatment relies on the best available research evidence, and all other necessary inputs and factors to provide the best possible treatment. Standards of care must be evidence-based, and not merely based on the evidence - the dichotomy being critical in contemporary health services research and practice. Evidence-based standards of care must rest on the best available evidence that emerges from a concerted hypothesis-driven process of research synthesis and meta-analysis. Health information technology needs to become an every-day reality in health services research and practice to ensure evidence-based standards of care. Current trends indicate that user-friendly methodologies, for the dissemination of evidence-based standards of care, must be developed, tested and distributed. They should include approaches for the quantification and analysis of the textual content of systematic reviews and of their summaries in the form of critical reviews and lay-language summaries. 相似文献
992.
993.
Discovering amino acid (AA) patterns on protein binding sites has recently become popular. We propose a method to discover the association relationship among
AAs on binding sites. Such knowledge of binding sites is very helpful in predicting protein-protein interactions. In this paper, we focus on protein complexes
which have protein-protein recognition. The association rule mining technique is used to discover geographically adjacent amino acids on a binding site of a
protein complex. When mining, instead of treating all AAs of binding sites as a transaction, we geographically partition AAs of binding sites in a protein complex.
AAs in a partition are treated as a transaction. For the partition process, AAs on a binding site are projected from three-dimensional to two-dimensional. And then,
assisted with a circular grid, AAs on the binding site are placed into grid cells. A circular grid has ten rings: a central ring, the second ring with 6 sectors, the third
ring with 12 sectors, and later rings are added to four sectors in order. As for the radius of each ring, we examined the complexes and found that 10Å is a suitable
range, which can be set by the user. After placing these recognition complexes on the circular grid, we obtain mining records (i.e. transactions) from each sector. A
sector is regarded as a record. Finally, we use the association rule to mine these records for frequent AA patterns. If the support of an AA pattern is larger than the
predetermined minimum support (i.e. threshold), it is called a frequent pattern. With these discovered patterns, we offer the biologists a novel point of view, which
will improve the prediction accuracy of protein-protein recognition. In our experiments, we produced the AA patterns by data mining. As a result, we found that
arginine (arg) most frequently appears on the binding sites of two proteins in the recognition protein complexes, while cysteine (cys) appears the fewest. In
addition, if we discriminate the shape of binding sites between concave and convex further, we discover that patterns {arg, glu, asp} and {arg, ser, asp} on the
concave shape of binding sites in a protein more frequently (i.e. higher probability) make contact with {lys} or {arg} on the convex shape of binding sites in
another protein. Thus, we can confidently achieve a rate of at least 78%. On the other hand {val, gly, lys} on the convex surface of binding sites in proteins is more
frequently in contact with {asp} on the concave site of another protein, and the confidence achieved is over 81%. Applying data mining in biology can reveal
more facts that may otherwise be ignored or not easily discovered by the naked eye. Furthermore, we can discover more relationships among AAs on binding sites
by appropriately rotating these residues on binding sites from a three-dimension to two-dimension perspective. We designed a circular grid to deposit the data,
which total to 463 records consisting of AAs. Then we used the association rules to mine these records for discovering relationships. The proposed method in this
paper provides an insight into the characteristics of binding sites for recognition complexes. 相似文献
994.
贵州万山汞矿区自然土壤汞污染特征 总被引:2,自引:1,他引:1
为阐明万山汞矿区自然土壤汞的污染情况,以汞矿开采冶炼区为起点,沿敖寨河和下溪河等间距(4 kin)分层采集0~30 cm厚度的河滩土、灌木土和林地土,测定了其汞含量,分析了自然土壤汞的空间分布特征.结果表明,矿区同种植被覆盖类型的土壤总汞的含量变化范围较大,河滩土为0.16~389 mg·kg-1、灌木土为0.09~312 mg·kg-1、林地土为0.05~299 mg·kg-1,空间分布特征表现为随距污染源距离的增加而降低;同一采样区内河滩土、灌木土、林地土中土壤总汞的含量依次降低,同一采样点的垂向剖面上总汞含量一般从表层向下依次降低. 相似文献
995.
996.
Goertzen MM Driessnack MK Janz DM Weber LP 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2011,154(4):420-426
Research at the Key Lake uranium mill (Saskatchewan, Canada) suggests effluent discharged from the mill affects energy stores of resident fish, but the mechanisms by which energy homeostasis is affected and the subsequent effects on swimming performance are unknown. In the present study larvae were collected from laboratory raised adult fathead minnow (Pimephales promelas) exposed to 5% diluted uranium mill effluent or control (dechlorinated municipal) water, and reared in the same treatments to 60 days post hatch (dph). Critical swimming speed (Ucrit) was significantly lower in effluent exposed 60 dph fish compared to control fish. Fish used in tests were considered fatigued and compared to fish without swim testing (non-fatigued). There were no differences in whole body glycogen or triglyceride concentrations between effluent exposed versus control fish. However, fatigued fish from both treatments had significantly lower triglycerides, but not glycogen, compared to non-fatigued fish from the same treatment. Whole body β–hydroxyacyl coenzymeA dehydrogenase activity was similar in fish from both treatments, but citrate synthase activity was significantly lower in effluent exposed fish. Our results suggest uranium mill effluent exposure in the laboratory affects aerobic energy metabolism and swimming performance in juvenile fathead minnow, which could affect wild fish survivability. 相似文献
997.
998.
Nguyen HM Baudet M Cuiné S Adriano JM Barthe D Billon E Bruley C Beisson F Peltier G Ferro M Li-Beisson Y 《Proteomics》2011,11(21):4266-4273
Oil bodies are sites of energy and carbon storage in many organisms including microalgae. As a step toward deciphering oil accumulation mechanisms in algae, we used proteomics to analyze purified oil bodies from the model microalga Chlamydomonas reinhardtii grown under nitrogen deprivation. Among the 248 proteins (≥ 2 peptides) identified by LC-MS/MS, 33 were putatively involved in the metabolism of lipids (mostly acyl-lipids and sterols). Compared with a recently reported Chlamydomonas oil body proteome, 19 new proteins of lipid metabolism were identified, spanning the key steps of the triacylglycerol synthesis pathway and including a glycerol-3-phosphate acyltransferase (GPAT), a lysophosphatidic acid acyltransferase (LPAT) and a putative phospholipid:diacylglycerol acyltransferase (PDAT). In addition, proteins putatively involved in deacylation/reacylation, sterol synthesis, lipid signaling and lipid trafficking were found to be associated with the oil body fraction. This data set thus provides evidence that Chlamydomonas oil bodies are not only storage compartments but also are dynamic structures likely to be involved in processes such as oil synthesis, degradation and lipid homeostasis. The proteins identified here should provide useful targets for genetic studies aiming at increasing our understanding of triacyglycerol synthesis and the role of oil bodies in microalgal cell functions. 相似文献
999.
For almost three decades, open cut coal mines have been expanding deeper into the densely settled agricultural landscape of the Hunter Valley, New South Wales. The mines have become increasingly profitable for Australian and multinational companies, and Newcastle, the capital of the Hunter region, is now the world's largest black coal exporting port. Despite the significant new wealth that mining has brought, those residing in proximity to mines and coal-fired power stations in the Hunter Valley have long struggled against the deleterious effects on health, rural livelihoods and environment. In recent years, opposition has widened to a more activist environmentalism that links the coal economy to climate change, global warming and other cumulative health and environmental effects. The organisational scale of the opposition has correspondingly widened to interconnect local residents, Green political parties and transnational organisations such as Greenpeace and the World Wildlife Fund. Using the Anvil Hill open cut mine proposal as an example, this paper examines the shifting grounds of environmental knowledge and oppositional practices by coal-affected residents of the Hunter Valley. 相似文献
1000.
Ciaran O'Faircheallaigh 《Ethnic and racial studies》2013,36(11):1789-1807
This article documents the agency of indigenous women in negotiations surrounding major resource projects on indigenous lands. The dominant view in the academic and activist literature is that indigenous women are excluded from negotiations, which helps explain their failure to share in project benefits. The author's experience as a negotiator for indigenous communities in Australia and his research in Canada reveals a different picture, indicating that indigenous women often play a central role in negotiations. The article seeks to explain the inconsistency between the findings reported here and much of the literature, in terms of a broader tendency in the latter to downplay the agency of women in relation to mining; and its failure to adequately recognize the multiple and complex ways in which indigenous women can influence negotiations, and the role of specific cultural, institutional and political contexts in shaping women's participation. 相似文献