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271.
Onivaldo Randig Florence Deau Marcilene F. A. dos Santos Myrian S. Tigano Regina M. D. G. Carneiro Philippe Castagnone-Sereno 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(3):485-495
The root-knot nematode (RKN) Meloidogyne mayaguensis is considered as one of the most damaging RKN species because of its extremely wide host range. Recent surveys have shown
the rapid spread of this parasite in agro-ecosytems, often making crop cultivation not viable in the heavily infested areas.
Here, we report the identification, molecular cloning, genomic organisation and sequence analysis of a new satellite DNA (satDNA)
family from M. mayaguensis (named pMmPet). It is comprised of two groups of A+T rich, tandemly repeated units of 174 and 180 bp, respectively. Using
these sequences as targets, hybridisation and PCR experiments performed on a wide collection of 44 populations belonging to
15 RKN species showed that the pMmPet family could only be detected in the 16 M. mayaguensis populations tested. In addition, because of their repetitive nature, positive detection of pMmPet sequences was achieved
in single individual nematodes. Therefore, the repeated sequence described here possesses features that make it an excellent
candidate for use as a specific and extremely sensitive tool for the accurate detection and identification of this invasive
pest on a routine basis. Clearly, monitoring the occurrence and spread of M. mayaguensis at the domestic and international levels are needed to avoid wholesale loss of agricultural resources in the infested regions. 相似文献
272.
Nermin Gözükirmizi Kasım Bajroviç Zeliha İpekçi Melih Boydak Tahsin Akalp Korhan Tunçtaner Hülya Balkan Hulki Tanrıyar Mehmet Çalıkoėlu Tijen Oėraş Öznur Özden Mümtaz Tulukçu Turan Tank 《Journal of Forest Research》1998,3(2):123-126
Plant regeneration from 9 clones ofPopulus tremula representing diverse genotypes originated from Turkey, has been studied in different media, such as Murashige and Skoog’s
Medium (MS), Aspen Culture Medium (ACM) and Woody Plant Medium (WPM) with appropriate supplements of growth regulators. Regeneration
efficiency on WPM containing 1 mg/l zeatin using stem explantsin vitro, was higher than on MS and ACM. In this system, the time required for shoot regeneration was 2 weeks, which was shorter by
two weeks than that of previous reports. A strong genotype dependence was observed among the tested nine clones. The regeneration
system, we describe here, did not involve the callus phase and thus was less prone to somaclonal variation. When adventitious
microshoots were cultured on WPM supplemented with 0.5 mg/l or 2 mg/l indole-3-butyric acid (IBA), root formation was obtained after 1 week of culture. Adaptation of regenerated plantletsin vivo was 100%. This system for micropropagation ofPopulus tremula is expected to be suitable for studies on transformation of genes involved in lignin biosynthesis via modification of lignin
content.
This study was a part of the Project No. 62-02-001 TUBITAK-MAN-GMBAE named “Investigations on Biogenetically Develop Poplar
Clones as a Raw Material for Pulp and Paper Industry” and financially supported by General Management of Turkish Pulp and
Paper Mills. 相似文献
273.
Lori R. Kogan Regina Schoenfeld-Tacher Allen A. Simon 《Journal of Veterinary Behavior: Clinical Applications and Research》2012,7(5):268-275
Dogs are kenneled in professional facilities for a variety of reasons; however, the kennel environment, even for short periods, is a potential psychogenic stressor for most dogs. Continual stress and the resultant anxiety are undesirable for both ethical and physiological reasons. One growing area of research pertaining to the welfare of kenneled dogs is environmental enrichment, including auditory stimulation. The current study investigated the impact of music (classical, heavy metal, and specifically designed/altered classical) on activity level, vocalization, and body shaking of 117 kenneled dogs. Results suggest that classical music leads to kenneled dogs spending more time sleeping (F8,354 = 12.24, P > 0.0001) and less time vocalizing (F8,354 = 3.61, P > 0.0005) than when exposed to other music types or no music. Heavy metal music, compared with other music types, appears to increase body shaking (F8,354 = 96.97, P > 0.0001), a behavior suggestive of nervousness. It is suggested that playing classical music in a shelter environment may help mitigate some of the stress inherent for many kenneled dogs. 相似文献
274.
Rubini AS Dos Santos Paduan K Perez RR Ribolla PE O'Dwyer LH 《Veterinary parasitology》2006,137(1-2):168-171
Feline Hepatozoon species from Brazil was molecular identified and characterized for the first time in S?o Paulo state, Brazil. Partial sequences of the 18S rRNA gene from the Hepatozoon from three naturally infected cats were analyzed. Sequences revealed that feline Hepatozoon was closely related to the canine Hepatozoon canis from Brazil. 相似文献
275.
Cambon E Gouzou F Pina M Barea B Barouh N Lago R Ruales J Tsai SW Villeneuve P 《Journal of agricultural and food chemistry》2006,54(7):2726-2731
The enzymatic properties of Plumeria rubra latex have been evaluated for the first time, showing a high activity in both hydrolysis and synthesis reactions, and compared to the biocatalytic behavior of babaco (Vasconcellea x Heilbornii cv.) latex. Both biocatalysts have been optimized by studying the various parameters that influence reaction kinetics. The optimum temperatures for hydrolysis reactions were 50 and 55 degrees C for babaco and Plumeria, respectively. The optimum pH for babaco latex was 7, whereas for Plumeria latex, two optimal pH values (4 and 7) were observed. With regard to esterification and acyl transfer reactions such as alcoholysis and interesterification, the influence of thermodynamic water activity on reaction yields was determined and correlated with water sorption and desorption isotherms. When babaco latex is used as a biocatalyst, optimal synthesis reaction yields are obtained when the enzymatic extract is stabilized at a water activity value of 0.38, which corresponds to a water content of 5.7%. This optimal level of hydration is located on the linear portion of the biocatalyst's sorption isotherm, where the water molecules exhibit high-energy interactions with the protein network. In synthesis reactions (esterification, alcoholysis, and interesterification) biocatalyzed by Plumeria latex, correlation between best reaction yields and water activity cannot be done. Indeed, the sorption isotherm plot has an atypical shape, indicating that water might be trapped in the latex matrix and, consequently, that the water content of the biocatalyst is highly dependent on the hydration history of the latex. 相似文献
276.
Kogika MM Lustoza MD Notomi MK Wirthl VA Mirandola RM Hagiwara MK 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(4):441-445
BACKGROUND: Chronic renal failure (CRF) is a common disease in dogs, and many metabolic disorders can be observed, including metabolic acidosis and calcium and phosphorus disturbances. Acidosis may change the ionized calcium (i-Ca) fraction, usually increasing its concentration. OBJECTIVE: In this study we evaluated the influence of acidosis on the serum concentration of i-Ca in dogs with CRF and metabolic acidosis. METHODS: Dogs were studied in 2 groups: group I (control group = 40 clinically normal dogs) and group II (25 dogs with CRF and metabolic acidosis). Serum i-Ca was measured by an ion-selective electrode method; other biochemical analytes were measured using routine methods. RESULTS: The i-Ca concentration was significantly lower in dogs in group II than in group I; 56% of the dogs in group II were hypocalcemic. Hypocalcemia was observed in only 8% of dogs in group II when based on total calcium (t-Ca) concentration. No correlation between pH and i-Ca concentration was observed. A slight but significant correlation was detected between i-Ca and serum phosphorus concentration (r = -.284; P = .022), as well as between serum t-Ca and i-Ca concentration (r = .497; P < .0001). CONCLUSION: The i-Ca concentration in dogs with CRF and metabolic acidosis varied widely from that of t-Ca, showing the importance of determining the biologically active form of calcium. Metabolic acidosis did not influence the increase in i-Ca concentration, so other factors besides acidosis in CRF might alter the i-Ca fraction, such as hyperphosphatemia and other compounds that may form complexes with calcium. 相似文献
277.
Guilherme Augusto Peres Silva Lígia Regina Lima Gouvêa Cecília Khusala Verardi Marcos Deon Vilela de Resende Erivaldo José Scaloppi Junior Paulo de Souza Gonçalves 《Euphytica》2013,189(3):343-350
Knowledge of the traits present in plant populations of a species is essential to carry out selection and breeding. The objective of the present study was to estimate the genetic parameters and correlate genetically and phenotypically the variables rubber yield, annual trunk girth increase, number of latex vessel rings and bark thickness in early measurement cycles. A total of 22 rubber tree progenies (Hevea brasiliensis) were assessed in three locations during three early measurement cycles. The bark thickness variable correlated significantly for the three increase measurements made in the locations of Jaú, Pindorama and Votuporanga. The progeny mean based joint hereditability showed mean values greater than individual plants and within progeny plants of 0.848, 0.286 and 0.242, respectively. The variables annual trunk girth increase and bark thickness are genetically correlated variables. Rubber yield is correlated genetically with bark thickness that permits simultaneous selection for the two characteristics. The early measurement cycles were efficacious for finding genetic variability among the genotypes. 相似文献
278.
Laima Česonienė Remigijus Daubaras Vytautas Tamutis Vilma Kaškonienė Paulius Kaškonas Vidas Stakėnas 《Journal of Sustainable Forestry》2013,32(8):791-808
Currently, the aim of modern forest management is not only timber production but also the protection of biodiversity. The initial effects of clear-cut logging on forest understory vegetation, soil and the diversity of litter beetles have been studied. We examined unstudied effects of clear-cutting disturbance on understory vascular plant species abundance, forest soils, and understory vegetation nutrients as well as beetle diversity one year after clear-cutting. Substantial changes in the prominence values and above-ground mass of forest-related vascular plant and moss species were detected. Clear-cuttings resulted in fast appearance of new light-loving plant species. The significant decrease in understory plant biomass influenced the reduction of nutrient pools in clear-cut areas after one year. The clear-cut logging negatively influenced the richness of species and the number of individuals of stenobiontic forest-related beetles in the forest litter. However, forest clear-cuttings were beneficial for eurytopic and open land species. 相似文献
279.
Boretti FS Sieber-Ruckstuhl NS Gerber B Laluha P Baumgartner C Lutz H Hofmann-Lehmann R Reusch CE 《Journal of Feline Medicine and Surgery》2009,11(4):286-292
To relate thyroid size to routine blood parameters and T(4) status the ventral neck of 161 cats with clinical signs consistent with hyperthyroidism was examined by two independent observers using a semi-quantitative palpation system. Thyroid gland size of each side was scored from 0 (non-palpable) to a maximum of 6 (>25 mm). In 127 of the 161 cats, at least one thyroid gland was palpable. The palpation score was significantly correlated with the T(4) concentration. The 17 hyperthyroid cats had significantly higher palpation scores than the 110 euthyroid cats. Euthyroid animals with a palpation score >or=3 were significantly older, had higher body weights, lower alkaline phosphatase, alanine aminotransferase, phosphate, and urine specific gravity, but higher lipase and creatinine concentrations than hyperthyroid cats. Our study demonstrates that although no reliable conclusion on the functional status of the thyroid can be drawn based on its size the likelihood of hyperthyroidism increases with increasing size of the gland. 相似文献
280.
Nass N Schoeps R Ulbrich-Hofmann R Simm A Hohndorf L Schmelzer C Raith K Neubert RH Eder K 《Journal of agricultural and food chemistry》2008,56(13):4987-4994
Bioactive peptides with a variety of effects have been described from several nutritive proteins. They exhibit antimicrobial, blood-pressure lowering, antithrombotic, immunomodulatory, and cholesterol-modulating effects. In this study, we have examined whether peptides derived from food proteins might influence bile acid synthesis. A reporter gene cell line that carries a cholesterol 7alpha-hydroxylase promoter fragment fused to firefly luciferase ( cyp7a-luc) was used to screen for nutritive peptides affecting cyp7a expression, the enzyme catalyzing the rate-limiting step in bile acid synthesis. Proteolytic hydrolysates were prepared from soy protein and bovine casein with pepsin, trypsin, chymotrypsin, and elastase and size fractionated using ultrafiltration. Several bioactive hydrolysates could be identified that inhibited luciferase expression. Also, an activation of kinase (AKT, ERK, p38-MAPK) signaling could be observed. Selected hydrolysates were further fractionated by reversed-phase HPLC. Bioactive HPLC-fractions were obtained from casein but not from soy hydrolysates; however, activity could not be recovered in single peak fractions. Peptides in such fractions were identified by mass spectrometry. Five selected peptides from alpha S1-casein present in active fractions were synthesized, but none of these showed activity in the cyp7a-luc screening system. However, two of them activated MAP-kinase signaling similar to the hydrolysates, which suggests, that these peptides are involved in cyp7a regulation by the casein hydrolysates. 相似文献