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91.
Wegner K Robertson SA Kollias-Baker C Sams RA Muir WW 《Journal of veterinary pharmacology and therapeutics》2004,27(5):329-336
This study describes the pharmacokinetics of intravenous hydromorphone in cats and the simultaneous measurement of antinociceptive pharmacodynamic effects using a thermal threshold testing system. Following establishment of a baseline thermal threshold, six adult cats were administered 0.1 mg/kg of hydromorphone intravenously. Thermal threshold testing and blood collection were conducted simultaneously at predetermined time points. Plasma hydromorphone concentrations were determined by a liquid chromatographic-mass spectral method and pharmacokinetic analysis was performed by nonlinear least squares regression analysis. Plasma hydromorphone concentrations declined rapidly over time, and were below the limit of quantification of the assay (LOQ = 1.0 ng/mL) by 360 min. In contrast, thermal thresholds rose from a pretreatment value of 40.9 +/- 0.65 degrees C (mean +/- SEM) to instrument cut-out (55 degrees C) within 15 min and remained significantly elevated from 15-450 min after treatment. Inspection of the data revealed no direct correlation between plasma hydromorphone concentrations and the antinociceptive effect of this drug in cats. These findings support the importance of conducting pharmacokinetic studies in parallel with objective measurements of drug effect. 相似文献
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D.?EgamberdiyevaEmail author D.?Qarshieva K.?Davranov 《Biology and Fertility of Soils》2004,40(2):144-146
This research reports the effect of Bradyrhizobium spp strains on dry matter yield, nodulation and seed yield of soybean varieties grown in N-deficient soil in Uzbekistan in pot and field experiments, in 2001 and 2002. The results of experiments revealed that significant positive effects on growth, nodule number and yield of soybean were obtained after inoculation with Bradyrhizobium spp strains; and, generally, strains S62 and S63 were more effective than strain S61. The protein content of seeds also increased after inoculation. Both Orzu and Uzb2 soybean varieties gave a higher response than the Uzb6 variety. 相似文献
94.
Effects of mushroom and herb polysaccharides, as alternatives for an antibiotic, on growth performance of broilers 总被引:1,自引:1,他引:0
Guo FC Kwakkel RP Williams BA Li WK Li HS Luo JY Li XP Wei YX Yan ZT Verstegen MW 《British poultry science》2004,45(5):684-694
(1) This in vivo trial was conducted to study the effects of polysaccharide extracts of two mushrooms, Lentinus edodes (LenE) and Tremella fuciformis (TreE), and a herb, Astragalus membranaceus (AstE) on growth performance, and the weights of organs and the gastrointestinal tract (GIT) of broiler chickens. (2) Three extracts (LenE, TreE and AstE) were supplemented at inclusion rates of 0.5, 1, 2, 3 and 4 g/kg from 7 to 14 d of age and compared with an antibiotic treatment group (20 mg/kg, virginiamycin (VRG) as well as a group of non-supplemented birds. (3) Body weight (BW) gain, feed intake and feed conversion ratio (FCR) of the extract-supplemented groups were not significantly different from those of the antibiotic group. Significant effects of type of extract and concentration on growth performance were found from 7 to 28 d of age. Generally, birds fed with LenE showed higher BW gain and lower FCR from 7 to 28 d of age than those fed with TreE and AstE and 2 g/kg LenE was considered the optimal inclusion rate for enhanced broiler growth. However, the extracts had no significant effect on the relative weights of organs and GIT compared with the antibiotic group. (4) The birds fed the extracts showed better growth performance than the non-supplemented birds, but were not significantly different from those fed VRG. Of the three extracts, LenE appeared to be a potential growth promoter. Future studies are needed to investigate whether the extracts can be used as alternatives for antibiotic growth promoters in challenged birds, and to elucidate the mechanisms for potentially enhanced growth performance in poultry. 相似文献
95.
Johnson VS Ramsey IK Thompson H Cave TA Barr FJ Rudorf H Williams A Sullivan M 《The Journal of small animal practice》2004,45(3):134-143
Three dogs were presented for investigation of recurrent pyrexia of unknown origin, chronic vomiting and respiratory distress, respectively. One dog was markedly underweight and the other two were cachexic. Physical examination and initial diagnostic tests failed to establish the underlying cause of the presenting signs. Thoracic radiographs were within normal limits for the age of the dog. In each case there was a high index of suspicion for an occult neoplastic process in view of the profound unexplained weight loss present. High-resolution computed tomography (HRCT) of the thorax was performed. The lung fields were divided into three zones for analysis and a novel classification scheme was used to describe the HRCT findings in each zone. Postmortem examination and histopathology confirmed the presence of an infiltrating metastatic carcinoma in all three cases. The HRCT changes correlated closely with the pathological findings. The authors conclude that HRCT of the lung should be considered for pulmonary metastatic screening in the dog and introduce a classification system for HRCT findings, based on terminology used in human medicine. 相似文献
96.
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99.
The entomogenous nematode,Steinernema carpocapsae was applied in three forms in two fields cultivated with cotton and tomato, under each cotton seedling or tomato plant: a bait like form, a suspension and in irrigation water. High concentrations of 2000 and 1000 IJS/seedling induced 100% mortality (after 5 days), while lower concentrations showed the same result but after 15 days or later. Under all doses of nematode, bait form application was more effective than suspension or irrigated water. 相似文献
100.
St. Scheurer und K. Bauer-Dubau 《Anzeiger für Sch?dlingskunde》1999,72(1):14-18
During 1991 to 1997 4078 samples sent in by public and private institutions were tested for their attack by arthropods. 5994
determinations were done. Seven the store damaging species of Lepidoptera were observed.Plodia interpunctella was the prime pest (305 determinations, mainly in cornflakes, muesli, sunflower seeds, nuts, feed, milk porredge and chocolate
products). The percentage ofP. interpunctella increased from 4,3% (1991) to 5.6%–8.4% (for 1993). Larvae and adults and pure larvae samples ofP. interpunctella were mainly noticed from September to November.
Pure adults samples could be counted for the most part from March to September.
27 the store damaging Coleoptera-species were determined.Stegobium paniceum was the prime pest (164 samples).
4% of the samples involvedS. paniceum. Further mainly observed beetle-species were:Lasioderma serricorne (36 samples),Tenebrio molitor (in 75 samples) andTrogoderma angustum (134 samples).
Aktualisierte Fassung des auf der Jahrestagung des Arbeitskreises Medizinische Arachno-Entomologie der Deutschen Gesellschaft für Allgemeine und Angewandte Entomologie (K?ln/ Monheim, 1 und 2. 10. 1997) gehaltenen Vortrages. 相似文献
Aktualisierte Fassung des auf der Jahrestagung des Arbeitskreises Medizinische Arachno-Entomologie der Deutschen Gesellschaft für Allgemeine und Angewandte Entomologie (K?ln/ Monheim, 1 und 2. 10. 1997) gehaltenen Vortrages. 相似文献