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141.
Gibka J Wasiutyński A Skopińska-Rózewska E Siwicki AK Chorostowska-Wynimko J Sommer E Mazurkiewicz M Gliński M Skurzak H Wójcik R Jung L 《Polish journal of veterinary sciences》2010,13(1):105-115
The in vivo effects of some derivatives of aliphatic ketones (2-undecanone, 3-undecanone, 4-undecanone and their derivatives) on L-1 sarcoma tumor angiogenesis and VEGF content were studied in Balb/c mice. Mice that inhaled 10% solution of 3-undecanone(3-on) or 1% solution of 2-undecanone propylene acetal (Acpr2) for 3 days after tumor cells implantation, presented lower neovascular response measured by tumor-induced cutaneous angiogenesis test (TIA) and lower tumor VEGF content in 5-days tumors, than non-inhaled controls. Other substances presented various effects on tumor VEGF concentration and angiogenesis. Histological examination of lesions collected from mice inhaled Acpr2, or non-inhaled controls, revealed small diffused areas of necrosis in the former group. In both groups, slight to moderate inflammatory infiltrations were seen at the tumor's margin. In Acpr2 group, there were less small blood vessels at tumor's margin than in the control group. 相似文献
142.
Forest cover changes in the Prignitz region (NE Germany) between 1790 and 1960 in relation to soils and other driving forces 总被引:2,自引:1,他引:1
Decadal to centennial land-cover changes are important drivers of many environmental issues, including biodiversity, biogeochemical cycles and, especially, the global carbon balance. In general, changes are well documented over only a few decades. Studies of land-cover changes and its drivers over centuries are rare. Therefore, the main objectives of this study are (1) to trace the development of the actual pattern of forest-open land over 170 years, and (2) to associate land-cover classes with site conditions (soils) as well as with other driving forces during three periods (1790–1838, 1838–1870, and 1870–1960). For these purposes, we used a combined approach of GIS-techniques and historical reconstructions from archives. The shifts of percentages for established forests, afforestation, clearings and open land on different soils were checked using a chi square test. From the archives, we obtained information on demographic, political/institutional and economic/technological factors, which are assumed to be drivers for past land-cover changes. Percentages of most land-cover classes hardly differed between the periods. However, established forests remained mainly on sandy soils and, to a large extend, afforestation was realised on sandy soils. Clearings reached high percentages on fluvial sands and organic sediments in the early period. A complex of demographic, political/institutional and economic/technological factors also had a considerable impact on land use/cover change in the Prignitz region. Thus, in addition to the strong association of land-cover classes with soils, our study demonstrated that other driving forces, i.e. political and economic factors, played an important role in the full understanding of land use from the past to the present. 相似文献
143.
Aursand IG Gallart-Jornet L Erikson U Axelson DE Rustad T 《Journal of agricultural and food chemistry》2008,56(15):6252-6260
Low-field (LF) (1)H NMR T 2 relaxation measurements were used to study changes in water distribution in lean (Atlantic cod) and fatty (Atlantic salmon) fish during salting in 15% NaCl and 25% NaCl brines. The NMR data were treated by PCA, continuous distribution analysis, and biexponential fitting and compared with physicochemical data. Two main water pools were observed in unsalted fish, T 21, with relaxation times in the range 20-100 ms, and T 22, with relaxation times in the range 100-300 ms. Pronounced changes in T 2 relaxation data were observed during salting, revealing changes in the water properties. Salting in 15% brine lead to a shift toward longer relaxation times, reflecting increased water mobility, whereas, salting in saturated brines had the opposite effect. Water mobility changes were observed earlier in the salting process for cod compared to salmon. Good linear correlations ( F = 0.05) were found between T 2 parameters and water holding capacity, centrifugation loss, water activity, and salt content in the liquid phase for all fish groups. Fillet pH and total weight changes correlated linearly with T 2 parameters for some of the fish groups. 相似文献
144.
Background, Aims, and Scope As a consequence of human living and activity, water infiltration to the urban subsurface occurs from a variety of different
sources, like precipitation, irrigation, leaking pipes and sewers, septic tanks and rainwater infiltration ponds. This infiltration
is strongly related with quality issues of the infiltrated water and further impact on groundwater quality. In order to set
up an integrated urban water balance it becomes essential to estimate the infiltration processes, i.e. water flow and solute
transport, from these different infiltration sources and to take into account the large spatial variability of sediment properties,
the geometric settings of these sources and the groundwater table. For that purpose, the development of simple, physically-based
quantification approaches is required in order to establish an efficiently working prediction and risk analysis tool within
the framework of an integrated urban water management system. The scope of the presented work was to demonstrate the applicability
of the developed approaches at urban scale.
Methods Since a detailed, three-dimensional, numerical quantification of the infiltration processes within the entire urban area is
not possible, the individual sources were considered as independent within the EU AISUWRS project. Different models were developed
for balancing infiltration from areal and point sources with respect to the related flow pattern. The analytical model UL_FLOW,
based on one-dimensional, steady state analytical solutions, allows the estimation of conservative tracer residence times
in layered sediments under varying infiltration rates. The numerical model WSTM, based on a three-dimensional random walk
approach, calculates water and solute transport from pipe leaks. Additionally, the sources were classified in accordance to
the spatial distribution of the parameters determining the infiltration processes.
Results UL_FLOW was applied to data sets from the city of Rastatt within a case study of the AISUWRS project. Each neighbourhood of
water balance computation by the Urban Volume and Quality Model (UVQ) was defined as an areal infiltration source with unique
parameter values for sediment depth, profile and properties, as well as infiltration rate time series. Groundwater recharge
and residence time series were computed for each neighbourhood. Relevant statistical parameters obtained by time series analyses
from those time series could be mapped by GIS. Point infiltration, particularly from sewers, was classified due to the sediment
parameters and the distance to the groundwater table at each source location in order to reduce computational efforts. WSTM
computations provided time series of groundwater recharge and tracer breakthrough for some specific cases.
Discussion The analytical model UL_FLOW provides fast and efficient computation of groundwater recharge and residence times accounting
for storage effects within the unsaturated zone of urban areas. The reliability of this model has been shown by cross validation
with HYDRUS1D. Because of the high computational effort, WSTM could provide only short-term simulations for some specific
parameter sets for which residence time estimates could be derived.
Conclusions UL_FLOW provides an analytical modelling tool for balancing one-dimensional areal infiltration and estimating residence times
under varying conditions including spatial parameter variability. These balances could be used for assessing the impact of
those infiltration sources on groundwater quality. The tracer breakthrough from point infiltration sources computed by WSTM
could also be used for such kinds of assessment. The larger spatial parameter variability associated with these sources could
be handled by classification in GIS environments.
Recommendations and Perspectives Similar to the areal sources, a simple balance approach for point sources based on analytical solutions needs to be developed
for estimating residence times in order to avoid large computational efforts. Such a model would complete the balancing of
all kinds of infiltration sources in urban areas efficiently. Since the approaches are based on the balance of the physical
processes, they have a large predictive capability and could be included into an integrated urban water balance and management
system. The mapping of the statistical values of the residence times provides a tool to compare parts of the urban areas and
to visualize differences between urban water management scenarios. 相似文献
145.
146.
147.
E N Peterson R Kirby M Sommer K C Bovee 《Journal of the American Veterinary Medical Association》1991,199(7):904-906
A 4-month-old 2.5-kg sexually intact female domestic shorthair cat was referred to the teaching hospital because of suspected cholecalciferol intoxication after ingestion of a cholecalciferol-containing rodenticide. At referral, the cat was hypercalcemic, hyperkalemic, and acidotic. Despite management of hypercalcemia and preservation of renal function with physiologic saline solution, furosemide, dopamine, and calcitonin, the cat died, apparently as a result of extensive pulmonary mineralization. 相似文献
148.
H Bergner O Simon A Sommer R G?rsch Z Ceresnáková L Chrastinova J Szakacs M Stoyke 《Archives of Animal Nutrition》1985,35(10):733-745
The experiments were carried out on 3 bulls (body weight: 172, 229 and 193 kg), equipped with ileo-caecal cannulas and with catheters in the jugular veins on both sides. The offered pelleted ration consisted of straw 73%, molasses 12%, cereals 10%, ammonium hydrogen carbonate 3% and urea 2%. Feed intake amounted to about 3 kg per animal and day. During a preliminary period of 5 days 50% of ileal digesta were collected for 12 hours daily, deep-freezed and stored. In the main experiment 15N-urea was infused intravenously for 24 hours. During this period and during the following 6 hours ileal digesta were collected and replaced by precollected, unlabelled digesta. The urea metabolism was estimated by the 15N-labelling of blood urea, by the 15N-excretion via faeces and urea, by the appearance of 15N in ileal digesta and by the 15N-labelling of faecal NAN, NH3 and bacterial fraction. The time course of the 15N-labelling of plasma urea during infusion can be described by an exponential function. The urea flux rate was estimated from the calculated plateau value. The flux rate for the 3 animals was 28.8, 30.7 and 34.8 mumol per minute per kg0.75, respectively. During the infusion of 15N-urea 1.0-2.4% of the infused amount of 15N' appeared in ileal digesta, half of it in the TCA precipitable fraction. At the same time the 15N-labelling of faecal NH3 increased sharply, however, the 15N-labelling of the faecal bacterial fraction was smaller by one order of magnitude. Deficiency of fermentable substrates and problems of inhomogenity of the NH3 pool are supposed as reasons for this result. 30 to 50% of the urea flux entered the digestive tract, the direct entry of urea into the large intestine seems to be only very low. 相似文献
149.
Nonsurgical Transcatheter Coil Occlusion of Patent Ductus Arteriosus in Two Dogs Using a Preformed Nitinol Snare Delivery Technique 总被引:2,自引:0,他引:2
150.