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排序方式: 共有180条查询结果,搜索用时 15 毫秒
91.
92.
Agrawal N Frederick MJ Pickering CR Bettegowda C Chang K Li RJ Fakhry C Xie TX Zhang J Wang J Zhang N El-Naggar AK Jasser SA Weinstein JN Treviño L Drummond JA Muzny DM Wu Y Wood LD Hruban RH Westra WH Koch WM Califano JA Gibbs RA Sidransky D Vogelstein B Velculescu VE Papadopoulos N Wheeler DA Kinzler KW Myers JN 《Science (New York, N.Y.)》2011,333(6046):1154-1157
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. To explore the genetic origins of this cancer, we used whole-exome sequencing and gene copy number analyses to study 32 primary tumors. Tumors from patients with a history of tobacco use had more mutations than did tumors from patients who did not use tobacco, and tumors that were negative for human papillomavirus (HPV) had more mutations than did HPV-positive tumors. Six of the genes that were mutated in multiple tumors were assessed in up to 88 additional HNSCCs. In addition to previously described mutations in TP53, CDKN2A, PIK3CA, and HRAS, we identified mutations in FBXW7 and NOTCH1. Nearly 40% of the 28 mutations identified in NOTCH1 were predicted to truncate the gene product, suggesting that NOTCH1 may function as a tumor suppressor gene rather than an oncogene in this tumor type. 相似文献
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94.
Bettina Schelkle Elizabeth L Richards Donna Snellgrove Jo Cable 《Aquaculture Research》2016,47(9):2928-2936
Infectious diseases are a major welfare issue, economically costly and, from a conservation perspective, threaten susceptible fish populations. Parasite control in aquaculture is over reliant on a limited range of treatments which tend to be low in efficacy, toxic to hosts and have negative consequences on human health and the environment. Here, we tested 22 botanical treatments alongside five controls against Gyrodactylus turnbulli (Harris 1986), in vitro and in vivo, infecting guppies (Poecilia reticulata Peters 1859). Survival of detached parasites was significantly reduced by all treatments with cajuput oil, bay rum oil, bladderwrack, octanoic acid, pine tree oil and barberry killing worms instantly. In vivo, cajuput oil applied with emulsifier was as effective as a licensed livestock dewormer, Levamisole, which is not routinely prescribed for use in fish; hence, cajuput can be considered for further research to replace Levamisole in UK research laboratories as well as in ornamental aquaculture. 相似文献
95.
96.
Regenerating forest stands through natural seedlings is a commonly accepted silvicultural strategy in Germany. To plan for and increase natural regeneration within a given stand, foresters must be able to estimate whether the stand in its current state can produce sufficient saplings to replace the overstory. In this paper, we present two approaches to building a model that can estimate the probability of natural regeneration occurring, based on variables that are typically readily available from forest inventories. To estimate model parameters we used the large database of the third National Forest Inventory, which covers forest stands and sites across the whole of Germany, as well as weather and soil data. We examined how these variables impact the emergence of natural regeneration, ultimately fitting a model that can predict the occurrence of natural regeneration in 72% of cases. The influence of the variables on the predicted occurrence of natural regeneration was mixed, with most stand variables contributing only minor impact and most likely influencing natural regeneration via complex interactions. The exception was vertical structure (number of stand layers), which accounted for a large proportion of the goodness-of-fit of the model. An important finding was that forest ownership structure is a key variable for the prediction of the presence of regeneration. Data from this study support the assumption that some forest owners manage their stands in a way that fosters natural regeneration. 相似文献
97.
Heydens WF Healy CE Hotz KJ Kier LD Martens MA Wilson AG Farmer DR 《Journal of agricultural and food chemistry》2008,56(4):1517-1523
A broad array of in vitro and in vivo assays has consistently demonstrated that glyphosate and glyphosate-containing herbicide formulations (GCHF) are not genotoxic. Occasionally, however, related and contradictory data are reported, including findings of mouse liver and kidney DNA adducts and damage following intraperitoneal (ip) injection. Mode-of-action investigations were therefore undertaken to determine the significance of these contradictory data while concurrently comparing results from ip and oral exposures. Exposure by ip injection indeed produced marked hepatic and renal toxicity, but oral administration did not. The results suggest that ip injection of GCHF may induce secondary effects mediated by local toxicity rather than genotoxicity. Furthermore, these results continue to support the conclusion that glyphosate and GCHF are not genotoxic under exposure conditions that are relevant to animals and humans. 相似文献
98.
Sanjaya Gyawali Marinus L Otte Donna L. Jacob Jilal Abderrazek Ramesh Pal Singh Verma 《Journal of plant nutrition》2019,42(9):1036-1046
Multiple element analyses were carried out to investigate variation in element concentrations in barley grains of 336 genotypes. Of 13 elements analyzed, Ba ranged from 0.2 to 8.9?mg kg?1, Ca from 186.4 to 977.5?mg kg?1, Cu from 1.5 to 9.8?mg kg?1, K from 353.2 to 7721.5?mg kg?1, Mg from 1049.8 to 2024.2?mg kg?1, Mn from 8.1 to 22.9?mg kg?1, Na from 55.9 to 627.9?mg kg?1, P from 2272.9 to 5428.8?mg kg?1, S from 880.7 to 1898.0?mg kg?1, Si from 19.1 to 663.2?mg kg?1, and Sr from 0.35 to 2.62?mg kg?1 in the barley grain. The least square means showed high Zn, Fe, Mg, P, and S concentration in AM-64 and AM-228 genotypes. The principal component analysis of element concentration showed four PCs explained 64.3% total variance. Strong positive correlations (p?<?0.001) of Fe-Mn, Fe-S, S-Mn, Zn-P, Zn-Mg, Mg-P, Mg-Mn, and Ca-Sr were found. The identification barley genotypes that showed high elements concentration furnish valuable genetic resources for biofortification in future. 相似文献
99.
Noone TJ Millis DL Korvick DL Athanasiou K Cook JL Kuroki K Buonomo F 《American journal of veterinary research》2002,63(3):419-426
OBJECTIVE: To determine biomechanical and biochemical properties of the medial meniscus in a semi-stable stifle model and in clinical patients and to determine the effect of canine recombinant somatotropin hormone (STH) on those properties. ANIMALS: 22 healthy adult dogs and 12 dogs with meniscal damage secondary to cranial cruciate ligament (CCL) rupture. PROCEDURE: The CCL was transected in 15 dogs, and stifles were immediately stabilized. Implants releasing 4 mg of STH/d were placed in 7 dogs, and 8 received sham implants. Seven dogs were used as untreated controls. Force plate analysis was performed before surgery and 2, 5, and 10 weeks after surgery. After 10 weeks, dogs were euthanatized, and menisci from surgical and contralateral stifles were harvested. The torn caudal horn of the medial meniscus in dogs with CCL rupture comprised the clinical group. Creep indentation determined aggregate modulus (HA), Poisson's ratio (v), permeability (k), and percentage recovery (%R). Water content (%W), collagen content (C), sulfated glycosaminoglycan (sGAG) content, and collagen type-I (cI) and -II (cII) immunoreactivity were also determined. RESULTS: Surgical and clinical groups had lower HA, k, %R, C, sGAG, cI, and clI and higher %W than the non-surgical group. Surgical stifles with greater weight bearing had stiffer menisci than those bearing less weight. Collagen content was higher in the surgical group receiving STH than the surgical group without STH. CONCLUSIONS AND CLINICAL RELEVANCE: Acute stabilization and moderate weight bearing of the CCLdeficient stifle appear to protect stiffness of the medial meniscus. Normal appearing menisci from CCL-deficient stifles can have alterations in biomechanical and biochemical properties, which may contribute to meniscal failure. 相似文献
100.
Denno DM Klein EJ Young VB Fox JG Wang D Tarr PI 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2007,8(1):69-80
Gastrointestinal illnesses are common afflictions. However, knowledge of their etiology is often lacking. Moreover, most cases of infections with reportable enteric pathogens (Campylobacter jejuni, Escherichia coli O157:H7, Salmonella, Shigella, Yersinia, Cryptosporidia and Giardia) have sporadic modes of acquisition, yet control measures are often biased towards mitigation of risks discerned by outbreak analysis. To determine the etiology of unexplained diarrhea it is important to study populations that can be matched to appropriate controls and to couple thorough classic microbiologic evaluation on receipt of specimens with archiving and outgrowth capabilities. Research evaluations should address the potential roles of a broad panel of candidate bacterial pathogens including diarrheagenic E. coli, Listeria monocytogenes, Helicobacters and jejuni Campylobacters, and also apply novel massively parallel sequencing and nucleic acid detection technologies that allow the detection of viral pathogens. To fill voids in our knowledge regarding sources of known enteric pathogens it will be critical to extend case-control studies to assess risk factors and exposures to patients with non-epidemic illnesses and to appropriate controls. By filling these gaps in our knowledge it should be possible to formulate rational prevention mechanisms for human gastrointestinal illnesses. 相似文献