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141.
Diprosopus was diagnosed in six German Holstein calves born on different dairy farms. The degree of facial duplication varied from a partial doubling of the nostrils and upper jaw to complete duplication of the face with formation of two mouths, four eyes and four ears. Further calves descending from the same parents or dams and calves from the same farms were not affected. A joint pedigree was ascertained for the calves with diprosopus. Furthermore, a previously reported case of diprosopus could be traced back to the same ancestors of this pedigree. Consequently, we detected the first time a familial accumulation of diprosopus. Since the ancestors showed no signs of diprosopus and the frequency of diprosopus in German Holsteins is presumably low, an oligogenic inheritance is likely. Recessive genes or a combination of recessive and dominant genes may cause this anomaly.  相似文献   
142.
Severe adverse cutaneous reactions were documented in two dogs with acute skin lesions and systemic signs after exposure to several oral and injectable drugs. Because of the high morbidity and mortality rates of many severe cutaneous drug reactions and a poor response to supportive care, wound management, and conventional immunosuppressive therapy, human intravenous immunoglobulin (IVIG) was infused on 2 consecutive days (1 g/kg per day) after informed consent was received. Human IVIG, with supportive care, resulted in rapid resolution of dermatological and systemic signs in both dogs; this treatment may be considered in other cases of severe cutaneous drug reactions.  相似文献   
143.
We compared near-infrared observations of the recently discovered outer rings of Uranus with Hubble Space Telescope results. We find that the inner ring, R/2003 U 2, is red, whereas the outer ring, R/2003 U 1, is very blue. Blue is an unusual color for rings; Saturn's enigmatic E ring is the only other known example. By analogy to the E ring, R/2003 U 1 is probably produced by impacts into the embedded moon Mab, which apparently orbits at a location where nongravitational perturbations favor the survival and spreading of submicron-sized dust. R/2003 U 2 more closely resembles Saturn's G ring, which is red, a typical color for dusty rings.  相似文献   
144.
145.
We examined whether the decomposition rate of trembling aspen (Populus tremuloides) leaf litter differed when decomposed for one year in litter bags placed within adjacent monotypic stands of trembling aspen, Engelmann spruce, and lodgepole pine trees in four replicate blocks in the San Juan mountains of Colorado, and whether they were metabolized into different metabolic byproducts. Mass loss was 6-8% lower in pine stands than in spruce or aspen stands, but this trend was not significant (p = 0.27). Water-soluble leaf litter metabolites were characterized using ultra-performance liquid chromatography coupled to a quadrapole time-of-flight mass spectrometer (UPLC-MS). Aspen leaf litter metabolomes were highly chemically complex; thousands of unique molecular features were identified in each sample. Although many of the molecular features were common to litter decomposed in all three forest types, we identified a subset of features that differed in abundance among the forest types. Our results suggest that the decomposer communities associated with each forest type not only affected the overall decomposition rate, but also produced many compounds in the diverse suite of metabolic byproducts at different rates, which could be an important control on the long-term sequestration of C in soil organic matter.  相似文献   
146.
The activity of unrestrained (slaughter) horses during 1-hour-long, on-truck rest stops was quantified to help determine whether horses get meaningful rest during on-truck rest stops. A single-deck semi-trailer divided into three compartments and fitted with 12 video cameras was used to record behavior of five shipments of horses during transport lasting 16 to 20 hours. Each shipment consisted of a high-, medium-, and low-density group averaging 397 ± 6.5 kg/m2, 348 ± 5.2 kg/m2, and 221 ± 7.6 kg/m2, respectively. Horses were rested for 1 hour after 8 hours of transport and before unloading at the end of each transport. Two of the three groups in the trailer were provided water during each rest stop. Data were successfully collected for 13 groups of horses of varying ages, sexes, and breeds typical of slaughter horses. The high-density watered groups had increased activity during the first 10 minutes of the first and second rest stops, indicating the horses were interacting and maneuvering to get to the water. Activity in the medium- and low-density groups was much more variable, but when there was increased activity during the first 10 minutes of a rest stop, it was in groups that had access to water. No trends were evident for an increase in activity near the end of the rest stops. Activity during the first and second rest stops was similar, indicating that these horses were not fatigued to the point of reducing activity during rest stops after 16 to 20 hours of transport.  相似文献   
147.
Poultry manure (PM) contains a large proportion of phosphorus (P) in mineral-associated forms that may not be readily available for plant uptake. In addition, PM application influences both chemical and biotic processes, and can affect the lability of native soil P. To investigate the effects of PM on soil P availability, we grew ryegrass (Lolium perenne) in greenhouse pots amended with poultry manure. Biomass was harvested at 4, 8, and 16 weeks following PM application, with soil separated into rhizosphere and bulk fractions. Soil was sequentially extracted by H2O, 0.5 M NaHCO3, 0.1 M NaOH, and 1 M HCl, and inorganic P (Pi) and enzymatically hydrolyzable organic P (Poe) were quantitated. Root P concentrations were 37% higher and total P uptake 59% higher with PM application than Control. At week 16, there was 30% more labile-Pi (H2O- plus NaHCO3-Pi) in the rhizosphere with PM than in Control. Phosphodiesterase activity increased with PM application. Furthermore, acid phosphomonoesterase, alkaline phosphomonoesterase, and phosphodiesterase activities were all higher in the rhizosphere than in bulk soil at week 16 with PM, indicating that increased labile-Pi was due primarily to stimulation of soil phosphatases to mineralize NaOH-Poe. Soil pH increased with PM application and plant growth, and may have promoted P availability by decreasing sorption of Al- and Fe-associated inorganic and organic phosphates. These results demonstrate that whereas PM application may initially increase NaOH and HCl-Pi, these fractions can be readily changed into labile-P and do not necessarily accumulate as stable or recalcitrant P in soil.  相似文献   
148.
149.
Analysis of the hydrophilic fraction of cranberry juice by reversed-phase HPLC using an Aqua LUNA column with diode array or MS detection revealed the presence of quinic acid, malic acid, shikimic acid, and citric acid. For the first time, two iridoid glucosides were found in the juice. The two iridoid glucosides were shown to be monotropein and 6,7-dihydromonotropein by MS and NMR spectroscopy. A fast reversed-phase HPLC method for quantification of the hydrophilic carboxylic acids was developed and used for analyses of cranberry, lingonberry, and blueberry juices. The level of hydrophilic carboxylic acids in cranberries was 2.67-3.57% (w/v), in lingonberries 2.27-3.05%, and in blueberries 0.35-0.75%. In lingonberries both iridoid glucosides were present, whereas only monotropein was present in blueberries.  相似文献   
150.
Availability and leaching of dissolved inorganic N (DIN = NH4+ + NO3-) in soil were measured in a periodically flooded forest of the Central Amazon floodplain (várzea) during one terrestrial phase. Special emphasis was on the effects of a legume and a non-legume tree species. NH4+-N accounted for more than 85% of DIN even at the end of the terrestrial phase although it decreased throughout the experimental period. While extractable NO3-N was always low in the soil (less than 15% of DIN), the amount of leached NO3-N was in the same range as NH4+-N. Under the legume trees mean DIN contents of the topsoil were higher than under the non-legume trees. DIN leaching from the topsoil (0–20 cm) was significantly higher under the legume trees than at the other sites, also indicating a higher N availability. Therefore, despite considerable leaching legume trees may be an important source of N supporting a high biomass production of the várzea forest.  相似文献   
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