兔病毒性出血症与大肠杆菌混合感染的诊治

以发生于本市的一起兔病毒性出血症与大肠杆菌病混合感染的病例为题材，从发病情况、临床症状、病变、实验室检查、防治等几个方面作了详尽的阐述，为临床上治疗该病提供参考依据。     

Acute small intestinal obstruction associated with Parascaris equorum infection in young horses: 25 cases (1985–2004)

AIMS: To retrospectively evaluate the medical and surgical records of horses with acute small intestinal obstructions associated with Parascaris equorum infection; to describe the gastrointestinal lesions; and to determine the outcome of cases with such lesions.

METHODS: Records of 25 horses with acute small intestinal obstruction associated with P. equorum between 1985 and 2004 were reviewed to determine signalment, history, physical examination, surgical or post-mortem findings, and outcome.

RESULTS: All horses except one were less than 12 months old. Standardbreds were over-represented in the population studied. Sixteen horses (72%) had been administered anthelmintics, including pyrantel (n=8), ivermectin (n=7), and trichlorphon (n=1), within 24 h prior to the onset of colic. Of the 25 cases reviewed, 16 had simple obstructive ascarid impactions (SOAIs), and nine had complicated obstructive ascarid impaction (COAI) including volvulus (n=6) or intussusception (n=3), both concurrent with ascarid impaction of the small intestine. Short-term survival (discharge from hospital) occurred in 79% of horses treated for SOAI, and was 64% for all horses. Long-term survival (>1 year) occurred in 33% of horses with SOAI, and the overall long-term survival was 27% for all horses. Formation of adhesions was the most frequent finding associated with death for horses that did not survive long-term.

CONCLUSIONS AND CLINICAL RELEVANCE: The incidence of anthelmintic treatment within 24 h of the onset of colic in this study population (72%) was higher than that previously reported. Resistance of P. equorum to ivermectin recently reported in Ontario may be associated with increased ascarid burdens, predisposing horses to ascarid impaction. The long-term survival of these horses was better than that reported previously.     

Spontaneous emission spectrum in double quantum dot devices

A double quantum dot device is a tunable two-level system for electronic energy states. A dc electron current was used to directly measure the rates for elastic and inelastic transitions between the two levels. For inelastic transitions, energy is exchanged with bosonic degrees of freedom in the environment. The inelastic transition rates are well described by the Einstein coefficients, relating absorption with stimulated and spontaneous emission. The most effectively coupled bosons in the specific environment of the semiconductor device used here were acoustic phonons. The experiments demonstrate the importance of vacuum fluctuations in the environment for quantum dot devices and potential design constraints for their use for preparing long-lived quantum states.     

Novel chemotaxonomic markers of the Alternaria infectoria species-group

Two new structurally related metabolites, novae-zelandin A (1) and novae-zelandin B (2), as well as the novel metabolite 4Z-infectopyrone (3) were purified from extracts of filamentous fungi belonging to the Alternaria infectoria species-group. The structures were elucidated by a combination of 1D and 2D NMR spectroscopic data and MS data. 1-3 are important chemotaxonomic markers of the A. infectoria species-group and exhibit structures similar to those of known biologically active compounds, suggesting that they could be potential phytotoxins.     

Temperate intercropping of cereals for forage: a review of the potential for growth and utilization with particular reference to the UK

Cereals grown for forage are increasing in importance in the rations of ruminants in the UK and have the potential to supply high proportions of energy-rich forage in their diets. However, such diets usually require some degree of protein supplementation. Crop mixtures, generally referred to as intercrops, have the potential to boost the forage protein content of diets as well as having a number of agronomic benefits. In this paper, the growth and utilization of annual intercrops is reviewed with particular reference, where feasible, to temperate regions. General agronomic and feeding issues associated with cereal intercrops are outlined together with the practicalities of field-scale management of intercrops in highly mechanized systems. A number of cereal-based intercrop combinations are also considered, concentrating specifically on their value for forage production. The future potential for different combinations is discussed and research recommendations made.