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1.
CANINE BRAIN ANATOMY ON MAGNETIC RESONANCE IMAGES 总被引:1,自引:1,他引:0
Susan L. Kraft DVM Patrick R. Gavin DVM PHD Lyle R. Wendling MD Venkat K. Reddy BVSC PHD 《Veterinary radiology & ultrasound》1989,30(4):147-158
Magnetic resonance (MR) images of the canine brain were acquired during investigation of dogs with neurologic disease. A paramagnetic contrast medium was used for enhancement. MR provided images with excellent contrast between grey and white matter, as well as brain tissue and cerebrospinal fluid. Good resolution and anatomic detail of the canine brain were obtained. A series of images was compiled and labelled as a reference for MR anatomy of the canine brain. 相似文献
2.
Yuanyuan Zhao Laura A. Wendling Changhui Wang Yuansheng Pei 《Journal of Soils and Sediments》2017,17(4):889-900
Purpose
Chlorpyrifos can be effectively adsorbed by drinking water treatment residuals (WTR), ubiquitous and non-hazardous by-products of potable water production. The major metabolite 3,5,6-trichloro-2-pyridinol (TCP) was found to be much more mobile and toxic than its parent chlorpyrifos. To assess the feasibility of WTR amendment for attenuation of chlorpyrifos and TCP pollution, the sorption/desorption and degradation behavior of chlorpyrifos and TCP in WTR-amended agricultural soils was examined in the present study.Materials and methods
Two representative agricultural soils were sampled from southern and northern China, respectively. The soils were amended with WTR at the rates of 0, 2, 5, and 10 % (w/w). Batch sorption/desorption test were applied to investigate the sorption/desorption characteristics of chlorpyrifos and TCP in WTR-amended soils. The influence of WTR amendment on chlorpyrifos degradation and TCP formation was evaluated using the incubation test, and its effect on the soil bacterial abundance was further studied through DNA extraction and PCR amplification.Results and discussion
Results showed that WTR amendment (0–10 %, w/w) significantly enhanced the retention capacity of chlorpyrifos and TCP in both soils examined (P < 0.05). Fractionation analyses further demonstrated that the bioavailability of chlorpyrifos was considerably reduced by WTR amendment, resulting in a decreased chlorpyrifos degradation rate. The WTR amendment also significantly reduced the mobility of TCP formed in chlorpyrifos-contaminated soils (P < 0.001). The chlorpyrifos toxicity to soil bacteria community was largely mitigated following WTR amendment, resulting in increased total bacterial abundance.Conclusions
Results obtained in the present study indicate a great deal of potential for the beneficial reuse of WTR as soil amendments for chlorpyrifos and TCP pollution control.3.
4.
Progression from the juvenile to mature phase in woody plants is accompanied by changes in characteristics as diverse as adventitious rooting capacity, leaf morphology, canopy architecture, wood anatomy and reproductive development. Many concepts of phase change, the intensity and duration of changes that occur during the phase transition, and the practical consequences of plant maturation for growth and development, are poorly understood. Little is known about the physiological and environmental control of maturation in woody plants compared with herbaceous plants, and reliable markers of phase state have only been developed for a few species, mainly conifers. Understanding the mechanisms and forms of phase change is a prerequisite for achieving maturation or rejuvenation for applications such as seed production or clonal propagation. This review describes concepts, terminology and consequences of phase change, combining theoretical and practical aspects of tree maturation that relate to clonal forestry. 相似文献
5.
Risely Ferraz De Almeida Camila Haddad Silveira Raquel P. Mota Mara Moitinho Everton Martins Arruda Eduardo De Sá Mendonça Newton La Scala Beno Wendling 《Journal of Soils and Sediments》2016,16(10):2354-2364
Purpose
The mineralization/immobilization of nutrients from the crop residues is correlated with the quality of the plant material and carbon compartments in the recalcitrant and labile soil fractions. The objective of this study was to correlate the quality and quantity of crop residues incubated in the soil with carbon compartments and CO2-C emission, using multivariate analysis.Materials and methods
The experiment was conducted in factorial 4?+?2?+?5 with three replicates, referring to three types of residues (control, sugarcane, Brachiaria, and soybean), and two contributions of the crop residues in constant rate, CR (10 Mg ha?1 residue), and agronomic rate, AR (20, 8, and 5 Mg ha?1 residue, respectively, for sugarcane, soybean, and Brachiaria), evaluated five times (1, 3, 6, 12, and 48 days after incubation). At each time, we determined the CO2-C emission, nitrogen and organic carbon in the soil, and the residues. In addition, the microbial biomass and water-soluble, labile, and humic substance carbons fractionated into fulvic acids, humic acids and humin were quantified.Results and discussion
Higher CO2-C emissions occurred in the soil with added residue ranging from 0.5 to 1.1 g CO2-C m?2 h?1 in the first 6 days of incubation, and there was a positive correlation with the less labile organic soil fractions as well as residue type. In the final period, after 12 days of soil incubation, there was a higher relation of CO2-C emission with carbon humin. The sugarcane and soybean residue (20 Mg ha?1) promoted higher CO2-C emission and the reduction of carbon residue. The addition of residue contributed to an 82.32 % increase in the emission of CO2-C, being more significant in the residue with higher nitrogen availability.Conclusions
This study shows that the quality and quantity of residue added to soil affects the carbon sequestration and CO2-C emission. In the first 6 days of incubation, there was a higher CO2-C emission ratio which correlates with the less stable soil carbon compartments as well as residue. In the final period of incubation, there is no effect of quality and quantity of residue added to soil on the CO2-C emission.6.
Constance E. De Haan DVM Susan L. Kraft DVM PhD Patrick R. Gavin DVM PhD Lyle R. Wendling MD Merle L. Griebenow 《Veterinary radiology & ultrasound》1994,35(2):83-86
Detecting canine brain lesions on computed tomography (CT) or magnetic resonance (MR) scans can be difficult if the lesions do not enhance well following administration of intravenous contrast material. Changes in the shape and position of the ventricular system can be important in the diagnosis of such lesions. Normal variation within the canine ventricular system has not been documented. MR scans from 62 normal Labrador retriever type dogs were evaluated. Five dogs had symmetric enlargement of the ventricles, while nineteen dogs had mild to severe ventricular asymmetry. The incidence of asymmetry in normal dogs must be considered when using ventricular configuration as an indication of central nervous system abnormality. 相似文献
7.
Retrospective Review of 50 Canine Intracranial Tumors Evaluated by Magnetic Resonance Imaging 总被引:2,自引:0,他引:2
Susan L. Kraft Patrick R. Gavin DVM Phd Constance DeHaan Michael Moore Lyle R. Wendling Charles W. Leathers 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(4):218-225
Magnetic resonance imaging (MRI) was performed on 50 dogs with intracranial neoplasia. The following tumor features were assessed: axial origin, location, shape, growth pattern, MRI signal intensity, evidence for edema, and paramagnetic contrast enhancement. Histologic diagnoses included 5 intracranially invading nasal tumors, 7 pituitary tumors, 22 meningiomas, 6 choroid plexus tumors, 7 astrocytomas, 1 ependymoma, and 2 oligodendrogliomas. Axial origin, site, shape, and growth pattern were important diagnostic characteristics for tumor type. Signal intensity and contrast enhancement pattern allowed further differentiation. Characteristic MRI features that facilitate diagnosis and prognosis were identified. Accurate diagnosis of tumor type based on these features was not always possible because of similarities in MRI appearance for some tumors. Tissue biopsy remains necessary for definitive diagnosis of intracranial tumors. 相似文献
8.
N.C. Wendling D.C. Bencic J.J. Nagler J.G. Cloud R.L. Ingermann 《Fish physiology and biochemistry》2000,22(3):217-223
To further examine the concept of egg quality and the physiology of stored salmonid eggs, we investigated the effects of different oxygen tensions on the adenosine triphosphate (ATP) levels of unfertilized, activated, and fertilized chinook salmon (Oncorhynchus tshawytscha) eggs. The ATP levels of unfertilized chinook salmon eggs were 2.61±0.14 nmol ATP per egg (17.6±0.9 mol l–1 relative to cell water) and ranged from 1.98 to 3.63 nmol ATP per egg. The ATP content of unfertilized eggs maintained at 10 °C under 100% O2, 21% O2, and 100% N2 remained unaltered throughout a 120 h storage period. Storing eggs under identical conditions at 20 °C (in an effort to speed egg metabolism and ATP turnover) resulted in significant O2-independent decreases in ATP levels. However, ATP levels of unfertilized eggs exposed to 1 mmol l–1 potassium cyanide (a potent inhibitor of oxidative phosphorylation) at 10 °C were significantly decreased after 24 h and continued to decline throughout the 120 h maintenance period to about 30% of time=0 values. Maintenance with exogenous nutrients (5 mmol l–1 acetate plus 5 mmol l–1 pyruvate) over 120 h at 10 °C did not alter the ATP content of unfertilized eggs. Eggs activated by exposing them to 10 °C water for a few minutes showed a rapid decrease in ATP values, regardless of whether the eggs were fertilized or not. Following an initial 25% drop after fertilization, the ATP levels remained stable for the remainder (5 d) of the incubation period in eggs maintained in 10 °C water. Therefore, unfertilized chinook salmon egg ATP levels appear to be relatively stable and maintained by a low, cyanide-inhibitable metabolism. The stability of egg ATP levels may be one reason that salmonid eggs can be stored for several days while eggs from other fishes cannot. 相似文献
9.
de Sá Francielen Paola Gomes Erik Nunes de Almeida Maggioni Renata Wendling Ivar Helm Cristiane Vieira Sant’Anna-Santos Bruno Francisco Zuffellato-Ribas Katia Christina 《New Forests》2022,53(3):411-430
New Forests - In order to better understand the physiological and technical aspects of yerba mate vegetative propagation, the present study sought to evaluate the rhizogenic capacity of apical and... 相似文献
10.
Ivar Wendling Gilvano Ebling Brondani Leonardo Ferreira Dutra Fabrício Augusto Hansel 《New Forests》2010,39(3):343-353
An efficient production system, which can quickly produce high quality plants, is shown in this study of Liquidambar styraciflua. The mini-cuttings technique was used for ex vitro clonal propagation of three sweetgum clones. The semi-hydroponics system for production of propagules was also tested, and
the concentration of indole-3-butyric acid (IBA) for rooting was evaluated. Three adult clones, produced according to conventional
cutting processes, were used as mini-stumps and maintained in semi-hydroponics systems of medium size sand. Ten collections
of sprouts were prepared to evaluate the production of semi-hydroponics systems (mini-clonal hedges). Sprouts from collection
number six were used at different concentrations of IBA solution (0; 500; 1,000; 3,000 and 6,000 mg l−1) to test the mini-cuttings technique. The high survival rates of mini-stumps after ten collections (96.3%), and high annual
production per square meter (~2,953 mini-cuttings) showed that the mini-clonal hedges are viable to conduct sweetgum mini-stumps.
The formation of 62.5% of healthy plants after hardening under outdoor conditions showed that sweetgum could be successfully
propagated by the mini-cuttings technique. 相似文献