排序方式： 共有46条查询结果，搜索用时 15 毫秒
21.
Adsorption of polyvinylalcohol (PVA) in aqueous suspension has been used to measure the specific surface area (SSA) of a silicon dioxide, a goethite, a clay, and a sample of a topsoil, the latter before and after treatment with hydrogen peroxide. Surface areas were calculated from each of the plateaus of the isotherms derived from the Langmuir equation fitted to the data, using a value of 0.04268 nm2 for the molecular area of a monomer of PVA. We compared these SSA values with those measured by N2 adsorption. The SSA values of the silicon dioxide, the goethite and the clay are in excellent agreement with the corresponding N2‐BET areas. The removal of organic matter by H2O2 from the topsoil sample led to a marked increase in the SSA measured by the BET‐method. For this sample, the SSA measured by PVA was considerably larger than the one that was obtained by the BET‐method and showed only a little change after removal of SOM. 相似文献
22.
Nodulation signaling in legumes requires NSP2, a member of the GRAS family of transcriptional regulators 总被引：1，自引：0，他引：1
Kaló P Gleason C Edwards A Marsh J Mitra RM Hirsch S Jakab J Sims S Long SR Rogers J Kiss GB Downie JA Oldroyd GE 《Science (New York, N.Y.)》2005,308(5729):1786-1789
Rhizobial bacteria enter a symbiotic interaction with legumes, activating diverse responses in roots through the lipochito oligosaccharide signaling molecule Nod factor. Here, we show that NSP2 from Medicago truncatula encodes a GRAS protein essential for Nod-factor signaling. NSP2 functions downstream of Nod-factor-induced calcium spiking and a calcium/calmodulin-dependent protein kinase. We show that NSP2-GFP expressed from a constitutive promoter is localized to the endoplasmic reticulum/nuclear envelope and relocalizes to the nucleus after Nod-factor elicitation. This work provides evidence that a GRAS protein transduces calcium signals in plants and provides a possible regulator of Nod-factor-inducible gene expression. 相似文献
23.
Levinson DF Holmans PA Laurent C Riley B Pulver AE Gejman PV Schwab SG Williams NM Owen MJ Wildenauer DB Sanders AR Nestadt G Mowry BJ Wormley B Bauché S Soubigou S Ribble R Nertney DA Liang KY Martinolich L Maier W Norton N Williams H Albus M Carpenter EB DeMarchi N Ewen-White KR Walsh D Jay M Deleuze JF O'Neill FA Papadimitriou G Weilbaecher A Lerer B O'Donovan MC Dikeos D Silverman JM Kendler KS Mallet J Crowe RR Walters M 《Science (New York, N.Y.)》2002,296(5568):739-741
Reports of substantial evidence for genetic linkage of schizophrenia to chromosome 1q were evaluated by genotyping 16 DNA markers across 107 centimorgans of this chromosome in a multicenter sample of 779 informative schizophrenia pedigrees. No significant evidence was observed for such linkage, nor for heterogeneity in allele sharing among the eight individual samples. Separate analyses of European-origin families, recessive models of inheritance, and families with larger numbers of affected cases also failed to produce significant evidence for linkage. If schizophrenia susceptibility genes are present on chromosome 1q, their population-wide genetic effects are likely to be small. 相似文献
24.
25.
Claudia?GeorgiEmail authorView author&#;s OrcID profile Daniel?Spengler Sibylle?Itzerott Birgit?Kleinschmit 《Precision Agriculture》2018,19(4):684-707
In light of the increasing demand for food production, climate change challenges for agriculture, and economic pressure, precision farming is an ever-growing market. The development and distribution of remote sensing applications is also growing. The availability of extensive spatial and temporal data—enhanced by satellite remote sensing and open-source policies—provides an attractive opportunity to collect, analyze and use agricultural data at the farm scale and beyond. The division of individual fields into zones of differing yield potential (management zones (MZ)) is the basis of most offline and map-overlay precision farming applications. In the process of delineation, manual labor is often required for the acquisition of suitable images and additional information on crop type. The authors therefore developed an automatic segmentation algorithm using multi-spectral satellite data, which is able to map stable crop growing patterns, reflecting areas of relative yield expectations within a field. The algorithm, using RapidEye data, is a quick and probably low-cost opportunity to divide agricultural fields into MZ, especially when yield data is insufficient or non-existent. With the increasing availability of satellite images, this method can address numerous users in agriculture and lower the threshold of implementing precision farming practices by providing a preliminary spatial field assessment. 相似文献
26.
Neumann S Welling H Thuere S 《Journal of the American Animal Hospital Association》2007,43(4):193-200
Because essential amino acids are metabolized in the liver, liver diseases may impair their catabolism. In this study, serum L-phenylalanine concentrations in 28 dogs with liver diseases were compared with those of 28 healthy dogs and 13 dogs with nonhepatic diseases. Dogs with liver diseases had significantly increased L-phenylalanine serum concentrations compared to healthy dogs (P<0.001) and to those with nonhepatic diseases (P<0.01). There were no significant differences among the L-phenylalanine serum concentrations of dogs with different degrees of liver diseases. The sensitivity and specificity of L-phenylalanine to fasting bile acids were comparable. 相似文献
27.
Melches S Mellema SC Doherr MG Wechsler B Steiner A 《Veterinary journal (London, England : 1997)》2007,173(3):554-563
Seventy male lambs over 10 weeks of age were castrated using Burdizzo, rubber rings, or surgery to assess the acute and long-term effects of castration. All castrations were performed under local anaesthesia. The surgically castrated lambs were additionally sedated with xylazine and the sedation reversed with tolazoline. The frequency of abnormal postures and immediate behavioural responses indicated that surgically castrated lambs were most distressed; the lambs castrated using Burdizzo and rubber rings were not dissimilar to those of the control group. Between 1.5 and 9 h after castration, signs of pain and distress were at a lower level in lambs anaesthetised with bupivacaine compared with those treated with lidocaine. Due to the markedly faster wound healing, Burdizzo castration seemed to be preferable (fewer signs of long-term pain) when compared to the rubber ring technique. It was concluded that local anaesthesia with bupivacaine, followed by the Burdizzo method is the preferable technique for the castration of lambs older than 10 weeks of age. 相似文献
28.
A pilot study comparing a protocol using intermittent administration of glargine and regular insulin to a continuous rate infusion of regular insulin in cats with naturally occurring diabetic ketoacidosis 
下载免费PDF全文
下载免费PDF全文 29.
Impact of contaminants bound to suspended particulate matter in the context of flood events 总被引：1，自引：0，他引：1
Jan Wölz Michael Fleig Tobias Schulze Sibylle Maletz Urte Lübcke-von Varel Georg Reifferscheid Dirk Kühlers Thomas Braunbeck Werner Brack Henner Hollert 《Journal of Soils and Sediments》2010,10(6):1174-1185
Purpose
The presented study investigated on contamination of suspended particulate matter (SPM) in rivers that was sampled long-term and with higher frequency during a flood event at the river Rhine. It was conducted to determine in vitro biological effects as well as to identify and quantify compound classes and effective contaminants. Research was part of investigation on hazards of contaminants bound to SPM to inundated sites and retention areas that are inundated during flood events. 相似文献30.