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31.
Two cumulene carbenes, H2C5 and H2C6, were detected in a supersonic molecular beam by Fourier transform microwave spectroscopy. Their rotational and leading centrifugal distortion constants were determined with high accuracy, such that the entire radio spectrum can now be calculated. Like the known carbenes H2C3 and H2C4, both molecules have singlet electronic ground states and linear carbon-chain backbones. They can be produced in sufficiently high concentrations in the laboratory that their electronic spectra, expected to lie in the visible, should be readily detectable by laser spectroscopy. The microwave spectra of other, more exotic isomers may be detectable as well.  相似文献   
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SUMMARY Four dogs with disseminated aspergillosis caused by Aspergillus terreus were treated with oral itraconazole for 190 to 1095 days. Infection was eliminated in 1 dog. Two dogs were treated for 1000 and 1095 days but were eventually euthanased 572 and 485 days after treatment was stopped. At necropsy both dogs had widespread aspergillosis. The fourth dog was euthanased for other reasons after 190 days of treatment when it was showing a good clinical response although there was radiographic evidence that the disease was progressing.  相似文献   
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Background

The prevalence of concurrent disease in hyperthyroid cats is unknown.

Objectives

To identify the prevalence of concurrent intra‐abdominal disease using abdominal ultrasound examination (AUS) in hyperthyroid cats referred for radioactive iodine treatment (RIT) and to determine whether the requirement for pretreatment AUS is justified.

Animals

Five hundred and thirty‐four client‐owned cats diagnosed with hyperthyroidism and referred for RIT.

Methods

Retrospective study. Age, breed, sex, body weight, clinical signs, total serum T4 concentration, blood urea nitrogen (BUN) concentration, serum creatinine concentration, urine specific gravity (USG), AUS results, and biopsy or cytology results, or both (if obtained) were collected from the medical records.

Results

The prevalence of concurrent disease identified using AUS in hyperthyroid cats referred for RIT was 36.1%; 22.8% of the cats in the study had renal disease and 2.4% had confirmed neoplasia. Significant differences in median USG (P value 0.032) and median BUN (P value 0.028) were found between cats that had abnormal kidneys on AUS compared to those with normal‐appearing kidneys. Only 2.2% of the cats were not treated with RIT as a result of changes identified on AUS and subsequently obtained cytology or biopsy results.

Conclusions and Clinical Importance

The results indicate that pretreatment AUS in hyperthyroid cats referred for RIT is unnecessary in most patients.  相似文献   
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AIMS: The aims of this study were (a) to evaluate the effect of xylazine and tolazoline, with and without lignocaine, on the cortisol response of calves following amputation dehorning and (b) to assess the effect of a non-steroidal anti-inflammatory drug (ketoprofen) and local anaesthesia on the cortisol response of calves to amputation dehorning.

METHODS: Plasma cortisol concentrations were measured in 100 dehorned or non-dehorned 3-month-old calves over an 8-h period following five different sedative/analgesic or control treatments. Sedative/analgesic treatments were: control (no anaesthesia); local anaesthesia and ketoprofen; local anaesthesia and xylazine; local anaesthesia, xylazine and tolazoline; and xylazine only. Within each sedative/analgesic treatment group, half the calves (n=10 per group) were amputation dehorned and half were not dehorned.

RESULTS: The change in plasma cortisol concentrations in calves dehorned after being given ketoprofen and local anaesthesia did not differ significantly from that of non-dehorned control calves for at least 8 h. In contrast, the cortisol response of dehorned calves not given analgesic drugs peaked 30 min after dehorning and lasted >4 h. Xylazine injected before dehorning significantly reduced but did not eliminate the peak of the cortisol response. When both xylazine and local anaesthesia were administered before dehorning the peak in the cortisol response was virtually eliminated. In the dehorned calves that received xylazine with or without local anaesthesia, cortisol concentration increased significantly 3 h after dehorning and did not return to baseline until at least 5 h later. When tolazoline was administered shortly after xylazine, it caused a marked cortisol response, higher than the response to any other treatment.

CONCLUSIONS: Combining ketoprofen and local anaesthesia minimised the cortisol response, and by inference the pain- induced distress, following amputation dehorning in calves. Xylazine reduced the initial cortisol response to dehorning but not as much as when local anaesthesia was also given. The increase in cortisol concentration from 3–8 h after dehorning in calves given xylazine alone or in combination with local anaesthesia suggests that calves experienced pain-induced distress during this time and that xylazine had no long-term analgesic effect. Tolazoline, used to reverse the sedative effects of xylazine, caused a marked cortisol response in calves via a mechanism which remains unclear.  相似文献   
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The objective of this study was to determine whether patient factors influence the concentration of the stromal vascular fraction (SVF) in fat for adipose-derived stromal cell (ASC) therapy in dogs. A total of 1265 dogs underwent adipose collection surgeries by veterinarians for processing by the Vet-Stem laboratory and data on cell counts and patient factors were collected. Body condition score (BCS) and breed size did not significantly affect the viable cells per gram (VCPG) of adipose tissue that represents the viable SVF. Age significantly affected the VCPG, with dogs in age quartile 1 having a significantly higher VCPG than those in quartile 2 (P = 0.003) and quartile 4 (P = 0.002). Adipose tissue collected at the falciform location had significantly fewer VCPG than tissue collected at the thoracic wall and inguinal locations (P < 0.001). When the interaction of gender and location was evaluated, there were significantly fewer VCPG in tissue collected at the falciform location than at the thoracic wall and inguinal locations in female spayed dogs (P < 0.001) and male neutered dogs (P < 0.001), but not in female intact dogs (P = 0.743) or male intact dogs (P = 0.208). It was concluded that specific patient factors should be taken into consideration in order to obtain the maximal yield of VCPG from an adipose collection procedure.  相似文献   
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A short-chain fatty acid (SCFA) burst feeding strategy to dry cows (periodically high SCFA concentration in the ruminal fluid) has been hypothesized to increase the ruminal surface area and absorptive capacity. The present paper deals with the effects of a SCFA burst feeding strategy on epithelial transport function in dry cows. The epithelial transport capacity for [14C]butyrate and Na+ across the rumen epithelium in vitro was significantly increased by the SCFA burst feeding strategy, compared with the controls. The transport of Cl- was significantly increased by the SCFA burst feeding strategy at the high feeding level, but non-significantly decreased at the low feeding level. The increase in transport capacity could not be attributed to changes in epithelial resistance, to the concentration of Na+/K+-ATP-ase or to the epithelial surface area and structure (data on epithelial surface area and structure were published by Andersen et al., Report No. 23 from the National Institute of Animal Science, Denmark, 1994). The observed changes in transport must reflect a change in either composition of the cell membranes or processes that facilitate transport through the cell, including metabolic processes. The presented results support the existence of a saturable SCFA transport system in the epithelial cells and the results show that the capacity of this transport system can be the subject for feed-induced regulation.  相似文献   
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