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1.
Alexandrov YN Crymov AA Kotelnikov VA Petrov GM Rzhiga ON Sidorenko AI Sinilo VP Zakharov AI Akim EL Basilevski AT Kadnichanski SA Tjuflin YS 《Science (New York, N.Y.)》1986,231(4743):1271-1273
From October 1983 to July 1984, the north hemisphere of Venus, from latitude 30 degrees to latitude 90 degrees , was mapped by means of the radar imagers and altimeters of the spacecraft Venera 15 and Venera 16. This report presents the results of the radar mapping of the Maxwell Montes region, one of the most interesting features of Venus' surface. A radar mosaic map and contour map have been compiled. 相似文献
2.
不同品种烤烟大田期几种营养元素积累与分配研究初报 总被引:11,自引:0,他引:11
2000年,研究了K326,红大,G28,NC82,K358,COKER371GOLD,云烟85这7个烤烟品种大田不同时期(移栽后20,40,60,80,100,120 d)N,P,K,S,Ca,Mg等6个营养元素的积累与分配差异。结果表明,移栽后40 d是N素的吸收高峰,不同品种对N素的吸收差异不大,N在各器官中的浓度大小依次是叶>根>茎;不同品种对P的吸收差异较大,其中移栽后20 d时差异最小,60 d时差异最大,大多数品种移栽后50 d前P的分布是根>叶>茎,50 d后叶中P的浓度逐渐增大; K的吸收高峰都在移栽后40~60 d,所有品种中,红大对K的吸收最多,移栽后20 d,茎中K的浓度最高,之后叶中K的浓度逐渐增加;移栽后20 d时,品种间对S的吸收差异较大,之后差异逐渐减小,S在不同品种中的分布略有差异,但有一个共同点,移栽后80 d前根中的浓度最大,之后叶中的浓度逐渐增大;多数品种移栽后对Ca的吸收都有一个顶峰,不同时期,Ca在叶中的浓度较大;不同品种对Mg的吸收差异不大,而且随着生育期的推移,总体上呈下降趋势,移栽后60 d前,根中的浓度最大,之后叶中的浓度超过茎和根中的浓度。 相似文献
3.
CASE: An 18-month-old male Sumatran tiger was referred for endoscopy and dilatation of an oesophageal stricture. Anaesthesia and bouginage was undertaken on eight occasions 2-3 weeks apart to dilate the oesophageal stricture. CLINICAL FINDINGS: On the first occasion, sedation was induced with a combination of medetomidine (30 microg/kg) and ketamine (2.35 mg/kg) given intramuscularly. Cardiopulmonary depression (characterised by bradycardia, ventricular arrhythmias, hypoventilation and cyanosis) was severe and in subsequent anaesthesias the medetomidine dose was decreased to about 18 microg/kg and the ketamine dose increased to about 3 microg/kg given intramuscularly. Immobilisation was adequate and the severity of the cardiopulmonary depression was reduced at the revised drug dosages. Atipamezole was effective in reversing both the cardiopulmonary and central nervous system depression. CONCLUSION: The dosage of medetomidine and ketamine recommended in the literature for immobilising tigers produced severe cardiopulmonary depression in this animal. A reduced dosage of medetomidine and higher dosage of ketamine provided adequate restraint with decreased cardiopulmonary depression. 相似文献
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5.
Salle CT Guahyba AS Wald VB Silva AB Salle FO Nascimento VP 《British poultry science》2003,44(2):211-217
1. Although the poultry industry uses state-of-the-art equipment and up-to-date services, in Brazil it generally makes decisions involving all its production variables based on purely subjective criteria. This paper reports the use of artificial neural networks to estimate performance in production birds belonging to a South Brazilian poultry farm. 2. Recorded data from 22 broiler production breeder flocks were obtained, from April, 1998 to December, 1999, which corresponded to 689 data lines of weekly recordings. 3. These data were processed by artificial neural networks using the software NeuroShell 2 version 4.0 (Ward Systems Group). The artificial neural network models generated were compared and selected based on their largest determination coefficient (R2), lowest Mean Squared Error (MSE), as well as on a uniform scatter in the residual plots. The authors conclude that it is possible to explain the performance variables of production birds, with the use of artificial neural networks. 4. The method allows the decisions made by the technical staff to be based on objective, scientific criteria, allows simulations of the consequences related to these decisions, and reports the contribution of each variable to the variables under study. 相似文献
6.
Wilmink JM Veenman JN van den Boom R Rutten VP Niewold TA Broekhuisen-Davies JM Lees R Armstrong S van Weeren PR Barneveld A 《Equine veterinary journal》2003,35(6):561-569
REASONS FOR PERFORMING STUDY: Wound healing proceeds faster in ponies than in horses and complications during healing, such as wound infection, occur less frequently in ponies. Earlier studies suggested that this difference might be related to differences in the initial post traumatic inflammatory response. HYPOTHESIS: That polymorphonuclear leucocyte (PMN) function and profiles of humoral factors in local inflammatory processes are different in horses and ponies. METHODS: PMNs were isolated from venous blood of horses and ponies. Chemotaxis and reactive oxygen species (ROS) production was determined. Tissue cages were implanted in limbs and necks of horses and ponies and injected with carrageenan and, 3 weeks later, with LPS. In sequential samples of inflammatory exudate, the numbers of macrophages and PMNs and the production of PGE2, TNFalpha, IL-1, IL-6 and chemoattractants were determined. RESULTS: In vitro ROS production of PMNs was significantly higher in ponies than in horses, whereas in vitro PMN chemotaxis was significantly lower in ponies. In the tissue cages for both stimuli, the production of IL-1 and chemoattractants was significantly higher in ponies than in horses and remained so towards the end of the observation period in ponies. CONCLUSIONS: This study demonstrated a higher production of various inflammatory mediators by pony leucocytes. Despite the lower in vitro chemotaxis of pony PMNs, this higher in vivo production resulted in a stronger initial inflammatory response in ponies, as has been reported in studies on wound healing, through the attraction of leucocytes and triggering of the production of other cytokines. A stronger initial inflammation may promote healing by more rapid elemination of contaminants and earlier transition to repair. POTENTIAL RELEVANCE: Modulation of the initial inflammatory response might therefore be a valid option for therapeutic intervention in cases of problematic wound healing. Further, the intraspecies differences in leucocyte function may have an impact on many fields in equine medicine. 相似文献
7.
da Rocha AC da Silva AB de Brito AB Moraes HL Pontes AP Cé MC do Nascimento VP Salle CT 《Avian diseases》2002,46(3):749-753
Sixty-three Escherichia coli strains isolated from broilers with respiratory problems were examined for virulence factors, hemolysin synthesis ability, motility, hemagglutination capacity, operon pap presence, colicin production, and serum resistance. The capacity to hemagglutinate guinea pig erythrocytes was found in 53 (84.1%) of the samples, but only 30 (47.6%) agglutinated chicken erythrocytes. D-mannose-sensitive hemagglutination against guinea pig erythrocytes was found in 19 (30.2%) samples and against chicken erythrocytes, in 15 (23.8%) samples, whereas the D-mannose-resistant hemagglutination with guinea pig erythrocytes was found in 34 (54%) samples, and 13 of these (20.6%) showed this characteristic against chicken erythrocytes. Operon pap, P fimbria codifier, was detected in 26 samples in a total of 34 D-mannose-resistant samples. Colicin production was observed in 55 (87.3%) of the strains, and 41.8% presented V colicin production. Of the samples analyzed, 56 (88.9%) presented serum resistance, six (9.5%) were intermediate, and only one (1.6%) was sensitive to the action of the complement. The diversity of virulence profiles detected in the samples in this study explains in part the multifactorial characteristics of avian colibacillosis. 相似文献
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9.
Atopic dermatitis (AD) is a chronic inflammatory skin disease in humans and dogs with comparable clinical features. Comparative studies of immunological events in the pathogenesis of AD may contribute to understanding of the disease in dogs and to development and evaluation of immunomodulatory strategies of relevance to both species.Both allergen-specific as well as non-specific mechanisms contribute to the disease development. AD skin lesions are proposed to be initiated by activation of allergen-specific Th2-type cells, potentially influenced by local cutaneous factors. In the chronic stage of skin lesions reactivity may change into a Th1-type, e.g. driven by eosinophil derived IL-12. Analyses of these processes in course of time were performed in both spontaneous as well as in experimentally induced lesions (i.e. atopy patch test (APT) lesions). In the present paper, the immunological events as reported for human and canine AD are summarized and compared. 相似文献
10.
Polymerase chain reaction (PCR) was used to amplify the spacer regions between the 16S and 23S genes of rRNA genetic loci of Salmonella serovars for their rapid identification. These genetic loci revealed a significant level of polymorphism in length across the species/serovar lines. When the 16S-23S spacer region amplification products were subjected to agarose electrophoresis, the patterns observed could be used to distinguish all the serovars of Salmonella tested. Unique elements obtained in amplification products were mostly clustered at serovar level, although certain genus-specific patterns were also observed. On the basis of the results obtained, the amplification of 16S-23S ribosomal spacer region could suitably be used in a PCR-based identification method for Salmonella serovars. 相似文献