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261.
The ratio of oleic to linoleic acids (O/L) and the tocopherol content are important features in determining peanut (Arachis hypogaea) seed shelf life. Soluble carbohydrates are known to be important precursors in roasted peanut flavor. The chemical qualities of Argentine grain are different from those of other countries, but no previous studies that associate grain quality and environmental parameters have been performed. Relationships were determined between O/L, tocopherol and sugar contents, and variations in temperature and rainfall during the grain filling period of Florman INTA peanuts. Dry seed yield was used as another explanatory variable. Multiple regression procedure gave mean temperature (positive coefficient) and total precipitation (negative coefficient) as the explanatory variables for variations in O/L. Total precipitation and dry seed yield (both negative coefficients) were found to be predictor variables for tocopherol and sugar contents. Total precipitation was an explanatory variable included in all of the linear regression models obtained in this study.  相似文献   
262.
Zusammenfassung In Zusammenarbeit zwischen der Akademie der Wissenschaften Kubas und der Deutschen Akademie der Wissenschaften zu Berlin wurden 1165 Pflanzenarten aus 149 Familien der kubanischen Flora nach Standardverfahren orientierend auf Alkaloide und Saponine untersucht. Die Ergebnisse sind in Tabelle 2 aufgeführt.
Phytochemical investigations in plants of the Cuban flora
Summary In cooperation of the Academy of Sciences of Cuba with the German Academy of Sciences at Berlin 1165 species from 149 plant families of the Cuban flora have been preliminarily investigated by standard methods with regard to the occurrence of alkaloids and saponins. The results are compiled in table 2.

1165 149 . . . 2.
  相似文献   
263.
Plants display a diverse array of inducible changes in secondary metabolites following insect herbivory. Herbivores differ in their feeding behavior, physiology, and mode of attachment to the leaf surface, and such variations might be reflected in the induced responses of damaged plants. Induced changes were analyzed for Minthostachys mollis, a Lamiaceae with medicinal and aromatic uses, and four species of folivore insects with different feeding habits (chewing, scraping, sap-sucking, and puncturing). In M. mollis leaves experimentally exposed to the insects, levels of the two dominant monoterpenes pulegone and menthone were assessed 24 and 48 h after wounding. Menthone content generally decreased in the essential oil of damaged leaves, whereas pulegone concentration increased in all treatments. These changes occurred also in the adjacent undamaged leaves, suggesting a systemic response. The relatively uniform response to different kinds of damage could be attributable to the presence of such a strongly active compound as pulegone in the essential oil of M. mollis. The effects of wounding on essential oil concentration may be significant from a commercial point of view.  相似文献   
264.
The lipid peroxidation product malondialdehyde is mostly bound to proteins in foods as an N-2-propenal derivative that is released as N-epsilon-(2-propenal)lysine by digestive enzymes. N-2-Propenals have been identified as the major forms of malondialdehyde in urine. To determine whether available lysine can be released from the N-2-propenals of lysine in vivo, two preparations containing N-epsilon-(2-propenal)lysine and N-alpha-(2-propenal)lysine or N,N'-di-(2-propenal)lysine were synthesized using radioactively labeled lysine and were administered to rats by gastric intubation and intraperitoneal injection. Both preparations were absorbed from the digestive tract, although not as efficiently as free lysine, but most of the radioactivity was excreted in urine. The radioactive label was also readily excreted after intraperitoneal injection. It is concluded that the N-2-propenals of lysine are fairly stable in vivo, so that, although they are absorbed from the gut, most of the absorbed material is not metabolized and is readily excreted as nonavailable lysine.  相似文献   
265.
The prevalence of Salmonella spp. infection was determined in 67 free-range pig herds in southern Spain. Microbiological assessment was performed on ileocolic lymph nodes collected at slaughter according to ISO 6579:2002 procedures. Overall, 33% of herds were infected and the prevalence of infection was 5.3%. Salmonella spp. serovars most frequently isolated were Anatum and Typhimurium, although uncommon serovars such as Hessarek and Mikawasima were also detected. Isolates were tested against 16 antimicrobial agents and exhibited resistance to streptomycin (46%), tetracycline (30%), sulphonamides (25%) and ampicillin (23%) by the break-point method. Multi-drug resistance, defined as resistance to ≥ 4 antimicrobials, was 36%.  相似文献   
266.
This paper provides macroscopic and histological evidence on the statistically significant protective effects of S3Pvac-phage vaccination against porcine cysticercosis and hydatidosis. The study included 391 rustically bred pigs (187 vaccinated and 204 controls). Vaccination significantly reduced the prevalence of cysticercosis by 61.7%. Vaccination also significantly reduced by 56.1% the prevalence of hydatidosis caused by Echinococcus granulosus in pigs. The presence of the vaccine epitopes in both cestodes is probably involved in the cross-protection observed. Increased inflammation was found in 5% of cysticerci recovered from controls, versus 24% from vaccinated pigs (P<0.01). Hydatid cysts were non-inflammatory in either group. Vaccination was effective to prevent one single disease, but it failed to prevent the simultaneous infections with both parasites in a same pig. The widening of the S3Pvac-phage vaccine protective repertoire to include hydatidosis is a convenient feature that should reduce the prevalence of two frequent zoonoses that affect rustic porcine breading with a single action. Thus, the costs of two different vaccination programs would be reduced to a single one with significant reduction in both zoonoses.  相似文献   
267.
The mammalian gastric and oral mucosa may be colonized by mixed Helicobacter and Campylobacter species, respectively, in individual animals. To better characterize the presence and distribution of Helicobacter and Campylobacter among marine mammals, we used PCR and 16S rDNA sequence analysis to examine gastric and oral samples from ten dolphins (Tursiops gephyreus), one killer whale (Orcinus orca), one false killer whale (Pseudorca crassidens), and three wild La Plata river dolphins (Pontoporia blainvillei). Helicobacter spp. DNA was widely distributed in gastric and oral samples from both captive and wild cetaceans. Phylogenetic analysis demonstrated two Helicobacter sequence clusters, one closely related to H. cetorum, a species isolated from dolphins and whales in North America. The second related cluster was to sequences obtained from dolphins in Australia and to gastric non-H. pylori helicobacters, and may represent a novel taxonomic group. Dental plaque sequences from four dolphins formed a third cluster within the Campylobacter genus that likely represents a novel species isolated from marine mammals. Identification of identical Helicobacter spp. DNA sequences from dental plaque, saliva and gastric fluids from the same hosts, suggests that the oral cavity may be involved in transmission. These results demonstrate that Helicobacter and Campylobacter species are commonly distributed in marine mammals, and identify taxonomic clusters that may represent novel species.  相似文献   
268.
OBJECTIVE: To determine the minimum anesthetic concentration (MAC) of isoflurane in thick-billed parrots (Rhynchopsitta pachyrhyncha). ANIMALS: 15 healthy thick-billed parrots. PROCEDURES: Anesthesia was induced and maintained with isoflurane in oxygen. In the first bird that was anesthetized, end-tidal isoflurane concentration was maintained at 1.0% for 15 minutes. After this period of anesthetic equilibration, an end-tidal gas sample was obtained for verification of isoflurane concentration. A toe was pinched to determine the bird's response to pain, and the bird was then allowed to recover from aesthesia. To determine MAC, a so-called up-and-down approach was subsequently used in all 15 birds. Compared with the isoflurane concentration used for MAC determination in the first bird, maintenance isoflurane concentration for the second bird was increased by approximately 10% if the first bird reacted and decreased by approximately 10% if the first bird did not react to a toe pinch. These steps were then followed until all 15 birds had been anesthetized. Crossover events occurred when birds in sequence had discordant results (ie, 1 reactor and 1 nonreactor). The MAC was defined as the mean of the isoflurane concentrations measured during these crossover events. RESULTS: Mean MAC of isoflurane in thick-billed parrots was estimated to be 1.07% (95% confidence interval, 0.97% to 1.16%). CONCLUSIONS AND CLINICAL RELEVANCE: Isoflurane MAC appears to be lower in thick-billed parrots than the MAC determined for other bird species. Determination of the species-specific requirements of thick-billed parrots should allow isoflurane anesthesia to be performed more safely in this endangered species.  相似文献   
269.
Eighteen Nellore and 18 Angus young bulls with BW of 381 ± 12 kg were randomly assigned into two feeding groups (whole shelled corn [WSC] or ground corn with silage [GC]) to evaluate the interaction of breed and diet on total nutrient digestibility, pancreatic α‐amylase, and maltase activity and SLC5A1expression in the small intestine. Experimental diets (DM basis) included (a) a diet containing 30% corn silage and 70% GC and soya bean meal‐based concentrate and (b) a diet containing 85% WSC and 15% of a soya bean meal‐ and mineral‐based pelleted supplement. The treatments were Nellore fed GC diet; Nellore fed WSC diet; Angus fed GC diet; and Angus fed WSC diet. Total faecal collection for the digestibility trial occurred from day 48 until day 50 of the experimental period. Feeding the WSC diet reduced DM and NDF intake (p < 0.01). Angus had greater DM and nutrient intake in kg/day (p < 0.01). However, there was no breed effect on DM and nutrient intakes based on percentage of BW (p > 0.19). Angus had greater starch digestibility (p = 0.03) than Nellore. Cattle fed the WSC diet had greater DM, NDF and starch digestibility (p < 0.01) compared with those fed the GC diet. The activity of pancreatic α‐amylase (U/g of protein) was greater in Nellore (p < 0.01) and was not affected by diet (p = 0.52). In duodenum, maltase activity (U/g of protein) was greater in bulls fed GC diet (p = 0.02). Expression of the gene SLC5A1was not affected by breed or diet (p > 0.05). In conclusion, Nellore had less capacity to digest starch. However, they did not have less pancreatic α‐amylase and duodenal maltase activity compared to Angus. The use of the WSC diet increases DM and total nutrient digestibility.  相似文献   
270.
ABSTRACT

The growth of cotton (Gossypium hirsutum L.) was evaluated in a 6 × 5 factorial experiment with 6 boron (B) levels (0.0, 0.5, 1.0, 1.5, 2.0, and 3.0 mg dm?3), 5 cultivars (‘CNPA 8H’, ‘BRS Aroeira’, ‘BRS Antares’, ‘BRS Sucupira’, ‘BRS Ipe’), and 3 replications. As B increased in the soil, leaf B concentrations increased linearly in ‘BRS Aroeira’ and ‘CNPA 8H’, and quadratically in ‘BRS Ipe’ and ‘BRS Sucupira’. The concentrations of B in the leaves and in the soil increased with the B increasing in the soil. The agronomic characteristics evaluated showed ‘BRS Aroeira’ and ‘BRS Sucupira’ responding more and BRS responding less to the B doses applied. The variation in the effFiciency of B utilization was: ‘BRS Aroeira’ > ‘CNPA 8H’ = ‘BRS Antares’ > ‘BRS Sucupira’ > ‘BRS Ipe’. Cultivar ‘BRS Aroeira’ had the greatest potential to respond positively to the addition of B to the soil.  相似文献   
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