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141.
Correa Mdo A Aguiar AJ Neto FJ Mendes Gda M Steagall PV Lima AF 《American journal of veterinary research》2007,68(9):932-940
OBJECTIVE: To evaluate the effects of 2 remifentanil infusion regimens on cardiovascular function and responses to nociceptive stimulation in propofol-anesthetized cats. ANIMALS: 8 adult cats. PROCEDURES: On 2 occasions, cats received acepromazine followed by propofol (6 mg/kg then 0.3 mg/kg/min, i.v.) and a constant rate infusion (CRI) of remifentanil (0.2 or 0.3 microg/kg/ min, i.v.) for 90 minutes and underwent mechanical ventilation (phase I). After recording physiologic variables, an electrical stimulus (50 V; 50 Hz; 10 milliseconds) was applied to a forelimb to assess motor responses to nociceptive stimulation. After an interval (> or = 10 days), the same cats were anesthetized via administration of acepromazine and a similar infusion regimen of propofol; the remifentanil infusion rate adjustments that were required to inhibit cardiovascular responses to ovariohysterectomy were recorded (phase II). RESULTS: In phase I, heart rate and arterial pressure did not differ between remifentanil-treated groups. From 30 to 90 minutes, cats receiving 0.3 microg of remifentanil/kg/min had no response to noxious stimulation. Purposeful movement was detected more frequently in cats receiving 0.2 microg of remifentanil/kg/min. In phase II, the highest dosage (mean +/- SEM) of remifentanil that prevented cardiovascular responses was 0.23 +/- 0.01 microg/kg/min. For all experiments, mean time from infusion cessation until standing ranged from 115 to 140 minutes. CONCLUSIONS AND CLINICAL RELEVANCE: Although the lower infusion rate of remifentanil allowed ovariohysterectomy to be performed, a CRI of 0.3 microg/kg/min was necessary to prevent motor response to electrical stimulation in propofol-anesthetized cats. Recovery from anesthesia was prolonged with this technique. 相似文献
142.
Fernandes MH Resende KT Tedeschi LO Fernandes JS Silva HM Carstens GE Berchielli TT Teixeira IA Akinaga L 《Journal of animal science》2007,85(4):1014-1023
Meat production by goats has become an important livestock enterprise in several parts of the world. Nonetheless, energy and protein requirements of meat goats have not been defined thoroughly. The objective of this study was to determine the energy and protein requirements for maintenance and growth of 34 (3/4) Boer x (1/4) Saanen crossbred, intact male kids (20.5 +/- 0.24 kg of initial BW). The baseline group was 7 randomly selected kids, averaging 21.2 +/- 0.36 kg of BW. An intermediate group consisted of 6 randomly selected kids, fed for ad libitum intake, that were slaughtered when they reached an average BW of 28.2 +/- 0.39 kg. The remaining kids (n = 21) were allocated randomly on d 0 to 3 levels of DMI (treatments were ad libitum or restricted to 70 or 40% of the ad libitum intake) within 7 slaughter groups. A slaughter group contained 1 kid from each treatment, and kids were slaughtered when the ad libitum treatment kid reached 35 kg of BW. Individual body components (head plus feet, hide, internal organs plus blood, and carcass) were weighed, ground, mixed, and subsampled for chemical analyses. Initial body composition was determined using equations developed from the composition of the baseline kids. The calculated daily maintenance requirement for NE was 77.3 +/- 1.05 kcal/kg(0.75) of empty BW (EBW) or 67.4 +/- 1.04 kcal/kg(0.75) of shrunk BW. The daily ME requirement for maintenance (118.1 kcal/kg(0.75) of EBW or 103.0 kcal/kg(0.75) of shrunk BW) was calculated by iteration, assuming that the heat produced was equal to the ME intake at maintenance. The partial efficiency of use of ME for NE below maintenance was 0.65. A value of 2.44 +/- 0.4 g of net protein/kg(0.75) of EBW for daily maintenance was determined. Net energy requirements for growth ranged from 2.55 to 3.0 Mcal/kg of EBW gain at 20 and 35 kg of BW, and net protein requirements for growth ranged from 178.8 to 185.2 g/kg of EBW gain. These results suggest that NE and net protein requirements for growing meat goats exceed the requirements previously published for dairy goats. Moreover, results from this study suggest that the N requirement for maintenance for growing goats is greater than the established recommendations. 相似文献
143.
Taylor DL Thomson PC de Silva K Whittington RJ 《Veterinary immunology and immunopathology》2007,115(1-2):43-55
Reference genes are frequently used to normalize between different biological samples the levels of mRNA measured using quantitative PCR (qPCR). The expression level of many commonly used reference genes has been shown to vary between tissues or cells, or following exposure to various treatments including infection with microbes. The selection of an appropriate reference gene for an individual experiment is therefore a crucial step in the process of accurately determining changes in gene expression. For this purpose, we analyzed the expression of nine commonly used reference genes in a murine macrophage cell line, RAW264.7, for their potential use in the analysis of differential gene expression by quantitative polymerase chain reaction (qPCR) following experimental infection with Mycobacterium avium subsp. paratuberculosis. Only one of nine putative reference genes tested, casc3a, was found to be suitable, and combinations of two or more reference genes were disadvantageous. Based on data from the study, we recommend an approach for selection of reference genes, conducting assays with technical replicates in duplicate rather than triplicate, determining decision-limit quality control criteria for technical replicates and assessing the significance of gene expression fold differences using DeltaDeltaC(t) based on knowledge of the variation in the reference gene. 相似文献
144.
C. Fortes Ferreira M. Gonzaga Pereira A. da Silva dos Santos R. Rodrigues R.E. Bressan-Smith A. PioViana R. Figueiredo Daher 《Euphytica》2003,134(1):43-46
Among the main causes of poor yield in common beans are fungal, viral and bacterial diseases. Common bacterial blight, caused
by Xanthomonas axonopodis pv. phaseoli (Xap), is one of the major bacterial diseases leading to significant losses in Brazil. Chemical control is ineffective, therefore,
the use of resistant varieties becomes an interesting alternative. The objective of the present work was to evaluate disease
resistance under natural infection of the pathogen in 109 recombinant inbred lines (F7) of P. vulgaris originated from the cross HAB-52 (susceptible — snapbean) × BAC-6 (resistant — common bean) in two different environments,
as well as to calculate genetic parameters to assist in the selection of promising materials to be used in the CBB resistance
breeding program. The data of the genetic parameters were
compared to those calculated for the F3 generation originated from the same cross. The heritability results for DI (disease index) and VI (variation index) in F3 were 26.85% and 0.26, respectively, whereas in F7 they were 91.77% and 1.36, respectively. These results demonstrate a potential to be explored for this advanced population,
that in the future, along with other pathogen variability studies and tests in other environments, may provide more information
regarding a more precise evaluation of promising genotypes to be used in common bean breeding programs aiming to obtain CBB
resistant varieties.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
145.
Effect of incubation temperature regimes and culture medium on broccoli microspore culture embryogenesis 总被引:8,自引:0,他引:8
João Carlos da Silva Dias 《Euphytica》2001,119(3):389-394
Conditions for reliable induction of embryogenesis from isolated microspores were studied in ten genotypes of broccoli. Embryo
yields were significantly increased in almost all of the broccoli genotypes by the incubation at 32.5 °C for 1 day, than when the standard incubation at 30 °C for 2 days was used. Treatments of 48 hours at 32.5 °C produced less than optimal results suggesting that broccoli microspores are more sensitive to high temperatures than those
of B. napus. The use of the 1/2 NLN-13 medium yielded greater number of embryos than the standard NLN-13. The magnitude of the response to the redution of
the concentration of major salts by half in the NLN medium varied with the different genotypes. High embryogenic broccoli
cultivars, such as ‘Shogun’, ‘SDB9’, and ‘Green Valiant’, presented a better response to the reduction of the concentration
of major salts by half in NLN-13. Reduction never produced a detrimental effect on embryo yield and seems not to have any
effect in the subsequent development of embryos in plants.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
146.
Eliana Gertrudes Macedo Lemos Cristina Lacerda Soares Petrarolha Silva Humberto Actis Zaidan 《Euphytica》2002,127(2):179-184
Brazil is currently the worlds largest producer of papaya (Carica papayaL.), producing fruits for both the domestic market and export. Only fruits from hermaphrodite plants are marketed because
they have the necessary commercial characteristics, i.e. they are pear-shaped and have thicker flesh and a smaller internal
cavity. Increased papaya yield has been limited mainly by the ratio of female to hermaphrodite (1: 2) plants normally occurring
in orchards. This ratio causes great losses to papaya producers and the identification of the sex of seedlings during the
nursery stage would be an important advance. In our study random amplified polymorphic DNA (RAPD) analysis was used to differentiate
between the sexual forms of three commercial C. papaya cultivars belonging to the Solo group. RAPD assays using the BC210 primer were able to detect hermaphrodites in all of the
cultivars tested. The BC210438molecular marker was much better at papaya sex differentiation than other markers described in the literature.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
147.
André M. Almeida Anabela B. Silva Susana S. Araújo Luís A. Cardoso Dulce M. Santos José M. Torné Jorge M. Silva Matthew J. Paul Pedro S. Fevereiro 《Euphytica》2007,154(1-2):113-126
We have previously obtained several lines of tobacco transformed with a trehalose-6-phosphate synthase gene of plant origin
(Arabidopsis thaliana), involved in the first step of the biosynthesis of trehalose, a known osmoprotectant. Two showed distinct intensity of expression:
high (B5H) and low (B1F). Such lines were analyzed for trehalose-6-phosphate content and the obtained results demonstrated
to be in accordance with the expression results. In order to study the responses of photosynthesis to water deficit of transgenic
lines in comparison to wild type (WT), three experiments were performed under different conditions: (1) Relative water (2)
Leaf gas exchange (3) Modulated Chlorophyll a Fluorescence. Different responses in RWC of plant lines to water withdrawal were detected, with transgenic line B5H indicating
less water loss after the water withdrawal period. Similar responses to water deficit regarding the leaf gas exchanges were
recorded for the three lines. When subjected to water deficit stress situations, higher F
v/F
m, ΦPSII and qP were detected for the transgenic lines. Under a SWC of 20% where higher values for such parameters were detected with
special relevance for the B5H line, indicating a possible higher ability to withstand severe drought stress and to resist
to prolonged periods without water than the B1F and WT lines. 相似文献
148.
Crossing patterns were investigated in an experimental garden of ethnovarieties ofManihot esculenta (Euphorbiaceae) inPiracicaba, São Paulo, Brazil. A model of evolutionary dynamics for cassava presupposes genetic recombination by means of crossing within cassava gardens as a source that amplifies genetic diversity. Quantitative analysis of mating system parameters was performed using progeny arrays assayed for eight allozyme markers. The multilocus outcrossing rate (t m)estimate (0.915±0.04)revealed that outcrossing was prevalent, but that a low level of self-pollination also occurred. The multilocus outcrossing rate ranged from 0.69 to 1.00 among eight varieties. The high value found for the outcrossing rate indicates that the ethnovarieties studied are preferentially allogamous. Genetic recombination occurred through crossing within the cassava garden, in agreement with an assumption of the model of evolutionary dynamics for this species. 相似文献
149.
FANG Zhi da 《保鲜与加工》2001,(6):91-94
This paper analyzes the key principles on which the international traditional contracts and new engineering contract have been drafted as well as the contractual relations among the parties involved in the execution of the project. This paper concluded that the new engineering contract prepared by the Institute of Civil Engineers has shown its unique features in the principles and new management techniques and is able to stimulate good project management. 相似文献
150.