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91.
92.
Cristian de la Fuente Martí Pumarola Sergio Ródenas Laia Foradada Albert Lloret Bernat Pérez de Val Sònia Añor 《Veterinary radiology & ultrasound》2012,53(6):655-659
Magnetic resonance (MR) imaging is highly sensitive for detecting tuberculomas in human patients but the specificity of the MR imaging features is low. Misdiagnosis with intracranial neoplasia is common, especially with dural‐based lesions or lesions located in the epidural space. We describe the MR imaging characteristics of an intracranial epidural tuberculoma caused by Mycobacterium tuberculosis infection in a dog. The intracranial mass and skull flat bone lysis and erosion are similar to those described in human caseating tuberculomas and can mimic intracranial neoplastic disease. 相似文献
93.
94.
The motility outcomes of boar semen frozen with newly developed freezing techniques using a new unique freezing technology (UFT) compared with traditional liquid nitrogen methodology were investigated with the intent of improving current fertility outcomes using semen. The UFT is an electronically controlled cooling chamber that houses an organic fluid bath that can be maintained at temperatures below 0 degrees C without solidifying to freeze samples. Four ejaculates from four different boars were collected for this trial. Samples were handled consistently during the pre- and post-freeze processing. From each ejaculate, samples were separated into eight cryopreservation treatment groups, six UFT variations and two control liquid nitrogen groups, immediately before freezing, in replicates of two. After the initial cryopreservation was complete, all samples were stored in liquid nitrogen for at least 48 h. Post-thaw motilities and original motility return percentages were assessed on a random, individual-sample basis. After the initial evaluations, samples from two boars were recollected and frozen using the UFT for breeding purposes. Four sows were bred with the UFT frozen semen to confirm fertility capability. When assessing the individual UFT techniques, all of six UFT techniques had improved post-thaw motilities. However, treatments F (micro = 29%, return micro = 37%) and J (micro = 27%, return micro = 34%) showed the highest statistical improvement for post-thaw (p < 0.05) and original motility percent returns (p < 0.05) when compared with either the control cryo-tube (micro = 15%, return micro = 19%) or straw groups (micro = 12%, return micro = 16%). The UFT semen had a 50% conception rate, with an average of seven piglets from the sows that farrowed. Our preliminary data suggest a higher motility return with a slower pre-freeze phase below the freezing point before the acceleration to liquid nitrogen temperatures. The preliminary data suggest that the UFT could be utilized as a potential cryopreservation option for boar semen. 相似文献
95.
96.
The interaction of carbofuran with carbage carboxylesterase was studied. The kinetic constants of carbamoylation and spontaneous reactivation were determined. The carbamoylation of cabbage carboxylesterase probably proceeds in a way similar to that of insect and/or animal acetylcholinesterase. 相似文献
97.
Objective To compare serological responses in pig herds classified as low or high risk for disease caused by Actinobacillus pleuropneumoniae, using two ELISA tests based on serovar‐independent antigens. Procedure Cross‐sectional sampling was undertaken in 13 commercial herds, the clinical and slaughter histories of which indicated either freedom from (n = 5) or prior confirmed cases of A. pleuropneumoniae (n = 8). In nine herds, approximately 40 pigs each were sampled at 4, 8, 12, 16 and 20 weeks. Three of the remaining four herds were sampled between 6 and 30 weeks of age, and the last was sampled only prior to slaughter, at approximately 24 weeks. Sera were tested in ELISA based on two antigens common among A. pleuropneumoniae serovars: a 39‐kDa outer membrane protein and a recombinant ApxIVA‐N terminus protein. Results Sampling of 1 and 5 to 6‐month‐old pigs provided the most useful information on herd status. The 39‐kDa ELISA was sensitive in detecting infected herds, but had evidence of cross‐reactivity with high seroreactivity rates in older pigs in some low‐risk herds. The ApxIVA‐N ELISA was less seroreactive in high‐risk herds and had higher specificity in low‐risk herds. Conclusion ELISA based on the 39‐kDa subunit are of limited use, because of possible cross‐reactivity, but a high negative predictive value may be useful for risk assessment in suspect herds. Maternal antibody to ApxIVA‐N may be of value in detecting high‐risk herds, but 5% of 4‐week‐old pigs in low‐risk herds were also seropositive in this assay. 相似文献
98.
Martin Kvác Bohumil Sak Dana Kvetonová Oleg Ditrich Lada Hofmannová David Modry Jirí Vítovec Lihua Xiao 《Veterinary parasitology》2008,153(3-4):363-367
Farm ruminants were infected experimentally with four mammalian gastric Cryptosporidium, namely Cryptosporidium andersoni LI03 originated from cattle and three isolates of Cryptosporidium muris from brown rat (isolate RN66), Bactrian camel (isolate CB03) and firstly characterized isolate from East African mole rat (isolate TS03). Sequence characterizations of the small-subunit rRNA gene showed that the LI03 isolate was C. andersoni and the other three isolates belonged to C. muris, although the TS03 isolate showed unique sequence variations (one single nucleotide change and four nucleotide insertions). C. andersoni LI03 was infectious for calves only, whereas lambs and kids were susceptible to C. muris CB03. C. muris TS03 and RN66 were not infectious for any farm ruminants. Infection dynamics including prepatent and patent period and infection intensity of the isolates used differed depending on the host species, but no clinical signs of cryptosporidiosis were observed in any of experimentally infected hosts. Cryptosporidium developmental stages were only detected in infected animals in the abomasum region. Histopathological changes were characterized by dilatation and epithelial metaplasia of infected gastric glands with no significant inflammatory responses in the lamina propria. 相似文献
99.
Comparison of numerical, analytical, and empirical models to estimate wetting patterns for surface and subsurface drip irrigation 总被引:2,自引:1,他引:1
Due to increasing competition for water resources by urban, industrial, and agricultural users, the proportion of agricultural
water use is gradually decreasing. To maintain or increase agricultural production, new irrigation systems, such as surface
or subsurface drip irrigation systems, will need to provide higher water use efficiency than those traditionally used. Several
models have been developed to predict the dimensions of wetting patterns, which are important to design optimal drip irrigation
system, using variables such as the emitter discharge, the volume of applied water, and the soil hydraulic properties. In
this work, we evaluated the accuracy of several approaches used to estimate wetting zone dimensions by comparing their predictions
with field and laboratory data, including the numerical HYDRUS-2D model, the analytical WetUp software, and selected empirical
models. The soil hydraulic parameters for the HYDRUS-2D simulations were estimated using either Rosetta for the laboratory
experiments and inverse analysis for the field experiments. The mean absolute error (MAE) was used to compare the model predictions
and observations of wetting zone dimensions. MAE for different experiments and directions varied from 0.87 to 10.43 cm for
HYDRUS-2D, from 1 to 58.1 cm for WetUp, and from 1.34 to 12.24 cm for other empirical models. 相似文献
100.
Francisco A Macías Francisco JR Mejías Jos MG Molinillo 《Pest management science》2019,75(9):2413-2436
Allelopathy is the biological phenomenon of chemical interactions between living organisms in the ecosystem, and must be taken into account in addressing pest and weed problems in future sustainable agriculture. Allelopathy is a multidisciplinary science, but in some cases, aspects of its chemistry are overlooked, despite the need for a deep knowledge of the chemical structural characteristics of allelochemicals to facilitate the design of new herbicides. This review is focused on the most important advances in allelopathy, paying particular attention to the design and development of phenolic compounds, terpenoids and alkaloids as herbicides. The isolation of allelochemicals is mainly addressed, but other aspects such as the analysis and activities of derivatives or analogs are also covered. Furthermore, the use of allelopathy in the fight against parasitic plants is included. The past 12 years have been a prolific period for publications on allelopathy. This critical review discusses future research areas in this field and the state of the art is analyzed from the chemist's perspective. © 2019 Society of Chemical Industry 相似文献