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81.
Physicochemical properties and amylopectin fine structures of A- and B-type granules of waxy and normal soft wheat starch 总被引:1,自引:0,他引:1
This work fractionated waxy and normal wheat starches into highly purified A- and B-type granule fractions, which were representative of native granule populations within parent native wheat starches, to accurately assess starch characteristics and properties of the two granule types. Wheat starch A- and B-type granules possessed different morphologies, granule specific surface area measurements, compositions, relative crystallinities, amylopectin branch chain distributions, and physical properties (swelling, gelatinization, and pasting behaviors). Within a genotype, total and apparent amylose contents were greater for A-type granules, while lipid-complexed amylose and phospholipid contents were greater for B-type granules. B-type (relative to A-type) granules within a given genotype possessed a greater abundance of short amylopectin branch chains (DPn < 13) and a lesser proportion of intermediate (DPn 13–33) and long (DPn > 33) branch chains, contributing to their lower relative crystallinities. Variation in amylose and phospholipid characteristics appeared to account for observed differences in swelling, gelatinization, and pasting properties between waxy and normal wheat starch fractions of a common granule type. However, starch granule swelling and gelatinization property differences between A- and B-type granules within a given genotype were most consistently explained by their differential amylopectin chain-length distributions. 相似文献
82.
Omaththage P. Perera Kerry C. Allen Devendra Jain Matthew Purcell Nathan S. Little Randall G. Luttrell 《Journal of insect science (Online)》2015,15(1)
Rapid identification of invasive species is crucial for deploying management strategies to prevent establishment. Recent Helicoverpa armigera (Hübner) invasions and subsequent establishment in South America has increased the risk of this species invading North America. Morphological similarities make differentiation of H. armigera from the native Helicoverpa zea (Boddie) difficult. Characteristics of adult male genitalia and nucleotide sequence differences in mitochondrial DNA are two of the currently available methods to differentiate these two species. However, current methods are likely too slow to be employed as rapid detection methods. In this study, conserved differences in the internal transcribed spacer 1 (ITS1) of the ribosomal RNA genes were used to develop species-specific oligonucleotide primers that amplified ITS1 fragments of 147 and 334 bp from H. armigera and H. zea, respectively. An amplicon (83 bp) from a conserved region of 18S ribosomal RNA subunit served as a positive control. Melting temperature differences in ITS1 amplicons yielded species-specific dissociation curves that could be used in high resolution melt analysis to differentiate the two Helicoverpa species. In addition, a rapid and inexpensive procedure for obtaining amplifiable genomic DNA from a small amount of tissue was identified. Under optimal conditions, the process was able to detect DNA from one H. armigera leg in a pool of 25 legs. The high resolution melt analysis combined with rapid DNA extraction could be used as an inexpensive method to genetically differentiate large numbers of H. armigera and H. zea using readily available reagents. 相似文献
83.
Objective To determine whether topical administration of the aldose reductase inhibitor Kinostat™ can ameliorate the onset or progression of cataracts in dogs with naturally occurring diabetes mellitus (DM). Materials and Methods A randomized, prospective, double‐masked placebo control pilot study was conducted with 40 dogs newly diagnosed with DM with no or minimal lens changes. Twenty‐eight dogs received Kinostat™ and 12 dogs received placebo. Procedures Owners administered the agent into both eyes three times daily for 1 year and compliance was monitored with log sheets. Complete ophthalmic examinations were performed on dilated eyes at the time of enrollment and 1, 2, 3, 6, and 12 months into treatment. Cataract severity was assessed on a scale of 0–3. At 12 months, full bloodwork, including HbA1C and blood KinostatTM levels were performed. Results After 12 months of treatment, the cataract score in the placebo group significantly increased with seven dogs (14 eyes) developing mature cataracts, two dogs (4 eyes) developing cortical opacities, and one dog (2 eyes) developing equatorial vacuoles with mild punctate cortical opacities. In contrast, the cataract score in the KinostatTM treated dogs was significantly less with seven developing anterior equatorial vacuoles, two developing incipient anterior cortical cataracts, and four developing mature cataracts. In fact, the cataract scores of the KinostatTM group at 12 months did not significantly increase from the score at the time of enrollment. The HbA1C values between the two groups after 12 months of treatment were similar, and no blood levels of KinostatTM were found in any enrolled dog. Conclusion The onset and/or progression of cataracts in dogs with DM can be significantly delayed by topical administration of Kinostat™. 相似文献
84.
85.
Root-knot nematodes cause substantial economic loss of yield in coffee plantations and vegetable crops in Cuba. At present, methods to control the nematodes are ineffective or inappropriate and alternatives are being sought. The nematophagous fungus Verticillium chlamydosporium (Goddard) was isolated from soils collected from coffee plantations and infected root-knot nematode eggs from roots of tomato plants grown in these soils. A total of 83 isolates were collected and identified morphologically as V. chlamydosporium var. chlamydosporium, V. chlamydosporium var. catenulatum, V. psalliotae, V. suchlasporium and an isolate of V. chlamydosporium var. chlamydosporium with unusually large dictyochlamydospores. From these, 24 that represented a range of origins were selected and screened for their ability to parasitize eggs of root-knot nematodes, colonize the rhizosphere of barley roots and produce chlamydospores. None of the isolates grew at temperatures below 15°C and V. suchlasporium grew at a faster rate at lower temperatures than the other isolates. These were also screened in the glasshouse and V. chlamydosporium var. catenulatum caused the greatest reduction in nematode populations. One isolate of each subspecies of V. chlamydosporium was tested with the standard, Rothamsted isolate 10, on a range of host plants. The greatest reduction in numbers of nematodes occurred on tomato plants (cv. Pixie). The Rothamsted isolate 10 reduced numbers of nematodes toa greater extent than the other isolates, and therefore has the greatest potential as a biological control agent of root-knot nematodes. 相似文献
86.
Heuter K 《Clinical Techniques in Small Animal Practice》2004,19(1):32-42
In veterinary patients, postgastric feeding is indicated for uncontrollable gastric vomiting, gastroparesis, biliary tract disease, pancreatitis, and for patients at increased risk for aspirating secondary to decreased mentation, prolonged recumbency, or an unprotected airway. Postgastric feeding may be implemented via the placement of a jejunal feeding tube. These tubes can be placed surgically (jejunostomy tubes) or with fluoroscopic or endoscopic guidance. This article will focus on methods of jejunal feeding-tube placement, advantages and disadvantages of the methods described, and complications associated with jejunal feeding. 相似文献
87.
Hendrick S Duffield T Leslie K Lissemore K Archambault M Kelton D 《The Canadian veterinary journal. La revue veterinaire canadienne》2005,46(12):1126-1129
This study randomly surveyed 50 dairy herds in Ontario; 18% and 30% of herds had 2 or more milk or serum enzyme-linked immunosorbent assay (ELISA)-positive cows, respectively. The apparent cow level prevalence was 1.7% and 2.6% on the milk and serum ELISA, respectively. The serum and milk assays agreed moderately. 相似文献
88.
Roussel AJ Libal MC Whitlock RL Hairgrove TB Barling KS Thompson JA 《Journal of the American Veterinary Medical Association》2005,226(5):773-778
OBJECTIVE: To estimate the prevalence of paratuberculosis in purebred beef cattle in Texas and identify risk factors for seropositivity. DESIGN: Epidemiologic survey. ANIMALS: 4,579 purebred cattle from 115 beef ranches in Texas. PROCEDURE: Blood was collected, and serum was analyzed for antibodies with a commercial ELISA. Fecal samples were collected and frozen at -80 degrees C until results of the ELISA were obtained, and feces from seropositive cattle were submitted for mycobacterial culture. Herd owners completed a survey form on management factors. RESULTS: Results of the ELISA were positive for 137 of the 4,579 (3.0%) cattle, and 50 of the 115 (43.8%) herds had at least 1 seropositive animal. Results of mycobacterial culture were positive for 10 of the 137 (7.3%) seropositive cattle, and 9 of the 50 (18%) seropositive herds had at least 1 animal for which results of mycobacterial culture were positive. Risk factors for seropositivity included water source, use of dairy-type nurse cows, previous clinical signs of paratuberculosis, species of cattle (Bos taurus vs Bos indicus), and location. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that seroprevalence of paratuberculosis among purebred beef cattle in Texas may be greater than seroprevalence among beef cattle in the United States as a whole; however, this difference could be attributable to breed or regional differences in infection rates or interference by cross-reacting organisms. Veterinarians should be aware of risk factors for paratuberculosis as well as the possibility that unexpected serologic results may be found in some herds. 相似文献
89.
Two dogs were presented with severe dermatopathies leading to cicatricial ectropion and severe surface ocular pathology. In one case, idiopathic sterile pyogranuloma was diagnosed on histopathology and managed with systemic immunosuppressive therapy. In the second case, demodicosis was diagnosed on skin scrapings and successfully treated with acaricidal medication. Following control of the underlying dermatopathies, both cases developed cicatricial ectropion as a result of scarring and contracture of eyelid tissue. Wharton-Jones (V-Y) blepharoplasties were performed on the affected eyelids and resulted in improved eyelid function and reduced corneal exposure in both cases. 相似文献