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排序方式: 共有384条查询结果,搜索用时 15 毫秒
81.
Jovin Hasjim Sun‐Ok Lee Suzanne Hendrich Stephen Setiawan Yongfeng Ai Jay‐lin Jane 《Cereal Chemistry》2010,87(4):257-262
Objectives of this study were to understand the physicochemical properties of a novel resistant starch (RS) made by complexing high‐amylose maize starch VII (HA7) with palmitic acid (PA), and its effects on reducing postprandial plasma‐glucose and insulin responses. The HA7 starch was heat‐treated and debranched using isoamylase (ISO) to enhance the starch‐lipid complex formation. The RS content of the HA7 starch debranched with ISO and complexed with PA (HA7+ISO+PA) was 52.7% determined using AOAC Method 991.43 for dietary fiber, which was greater than that of the HA7 control (35.4%). The increase in the RS content of the HA7+ISO+PA sample was attributed to the formation of retrograded debranched‐starch and starch‐lipid complex. The postprandial plasma‐glucose and insulin responses of 20 male human‐subjects after ingesting bread made from 60% (dry basis) HA7+ISO+PA were reduced to 55 and 43%, respectively, when compared with those after ingesting control white bread (as 100%) containing the same amount of total carbohydrates. The results suggested that the HA7+ISO+PA can be used for the interventions of insulin resistance and metabolic syndrome, including diabetes and obesity. 相似文献
82.
In many developing countries where rangelands are a dominant land type and critically important in livelihoods of a significant portion of the population, severe rangeland degradation and/or conflicts over rangeland use can create significant social, economic, and environmental problems. In this paper, we review rangeland degradation in the developing world, its impacts and causes, discuss problems in applying rangeland science to improve rangeland conditions, discuss the role of rangeland scientists, and discuss our approach for enhancing rangeland science in international development. We suggest range scientists can provide valuable input and direction on issues of rangeland degradation (including state changes and impacts on ecosystem goods and services), provide guidance in methods and realistic opportunities for rangeland improvement to local users, government, and development organizations, and work to provide pastoralists with adaptive management in variable ecosystems. Conflict and poverty can create situations where a long-term goal of sustainable rangeland use is overwhelmed by short-term needs of safety and food security; however, providing science and training on sustainable management can make a difference where conflicts are not too severe and can help promote societal stability. Negative perceptions about aid are widespread, but the needs for improved conditions associated with multiple values of rangelands, and the needs of people utilizing these areas, are great. Conducting planning and projects with transparency and accountability will help promote more inclusive participation and successful projects. To be effective, a project needs to consider the needs of the people utilizing the project area but also provide to these communities information on values of the rangelands to other stakeholders (ecosystem services). Sustainable projects will require accountability and enhance self-reliance to allow community empowerment and adaptability to changes. 相似文献
83.
Petrunewich MA Trimarchi JR Hanlan AK Hammer MA Baltz JM 《The Journal of reproduction and development》2009,55(1):30-38
ERK-type MAP kinase activity is required for normal first meiotic (MI) metaphase spindle dynamics and first polar body formation at the MI/MII transition, and for MII arrest until egg activation. MEK and MAPK, however, remain active until meiosis is completed and pronuclei form, but whether MEK/MAPK activity affects MII spindle function during egg activation has been unknown. Polarized light microscopy revealed that the MII spindle rapidly (within approximately 15 min) lost birefringence upon treatment of the egg with U0126, indicating decreased organization at the molecular level upon MEK inhibition. In contrast, birefringence rapidly increased when MPF was inhibited with roscovitine, and this was similar to the increased birefringence previously shown after fertilization or parthenogenetic activation with Sr(2+). Confocal microscopy indicated that many spindles in U0126-activated eggs had failed to rotate or were dissociated from the egg cortex. Subsequently, abnormally-located midbodies were evident in U0126-induced parthenogenotes. Thus, MEK/MAPK activity is required to maintain the ordered structure of the MII spindle and for normal spindle dynamics during second polar body formation. 相似文献
84.
Bhaskaran S Jay CM Berghman LR Wagner GG Waghela SD 《Veterinary research communications》2005,29(6):463-476
Bovine colibacillosis caused by enterotoxigenic Escherichia coli (ETEC) is a worldwide problem. Adhesion of ETEC to intestinal cell receptors mediated by the surface protein F5 fimbriae
is the initial step in the establishment of colibacillosis. Prevention of ETEC F5+ adhesion to enterocytes protects newborn calves against collibacillosis. On the enterocytes, the F5 fimbriae bind to a ganglioside
that is also found on horse red blood cells. Thus, the presence of F5 fimbriae induces haemagglutination, which is useful
as an indicator in a functional assay system. In this study, recombinant anti-F5 scFv antibody fragment produced in E. coli HB2151 reacted with F5 fimbriae in ELISA and Western immunoblot, and prevented haemagglutination induced by the binding of
the F5 fimbriae to its natural host receptors on horse red blood cells. Given the ease with which recombinant antibodies can
be mass-produced, the presently described scFv may hold promise as a prophylactic agent for colibacillosis. 相似文献
85.
Nutter FB Dubey JP Levine JF Breitschwerdt EB Ford RB Stoskopf MK 《Journal of the American Veterinary Medical Association》2004,225(9):1394-1398
OBJECTIVE: To compare seroprevalences of antibodies against Bartonella henselae and Toxoplasma gondii and fecal shedding of Cryptosporidium spp, Giardia spp, and Toxocara cati in feral and pet domestic cats. DESIGN: Prospective cross-sectional serologic and coprologic survey. ANIMALS: 100 feral cats and 76 pet domestic cats from Randolph County, NC. PROCEDURE: Blood and fecal samples were collected and tested. RESULTS: Percentages of feral cats seropositive for antibodies against B. henselae and T. gondii (93% and 63%, respectively) were significantly higher than percentages of pet cats (75% and 34%). Percentages of feral and pet cats with Cryptosporidium spp (7% of feral cats; 6% of pet cats), Giardia spp (6% of feral cats; 5% of pet cats), and T. cati ova (21% of feral cats; 18% of pet cats) in their feces were not significantly different between populations. Results of CBCs and serum biochemical analyses were not significantly different between feral and pet cats, except that feral cats had a significantly lower median PCV and significantly higher median neutrophil count. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that feral and pet cats had similar baseline health status, as reflected by results of hematologic and serum biochemical testing and similar prevalences of infection with Cryptosporidium spp, Giardia spp, and T. cati. Feral cats did have higher seroprevalences of antibodies against B. henselae and T. gondii than did pet cats, but this likely was related to greater exposure to vectors of these organisms. 相似文献
86.
Lisa A Harrenstien Linda Munson Lisa M Chassy Irwin K M Liu Jay F Kirkpatrick 《Journal of zoo and wildlife medicine》2004,35(3):271-279
Methods of contraception are necessary for management of zoo felids; however, the most commonly used contraceptive (melengestrol acetate implant) is associated with serious adverse reactions with long-term use. Porcine zona pellucida (pZP) vaccines are promising as contraceptives, but their safety in zoo felids has not been tested. pZP vaccine was administered to 27 female felids representing 10 species, including African lion (Panthera leo), Asian leopard (P. pardus), jaguar (P. onca), tiger (P. tigris), snow leopard (P. uncia), cougar (Felis concolor), Siberian lynx (F. lynx), Canada lynx (F. canadensis), serval (F. serval), and bobcat (F. rufus), in 15 facilities. Over 6 wk, each animal received three i.m. injections of 65 microg pZP with Freund's complete adjuvant (FCA), Freund's incomplete adjuvant, or carbopol as the adjuvant. Behavioral signs of estrus were seen in 14 of the vaccinated felids. An unacceptably high incidence of adverse reactions was seen including injection site swelling, lameness, limb swelling, or abscessation (or all) in five felids after injection with FCA as the initial adjuvant. Adverse behavioral signs, including increased irritability and aggression, were seen in four felids. Six of the felids were assayed for antibodies against pZP during the 12 mo after vaccination; all showed antibody production. Antibody levels appeared to peak 1-4 mo after vaccination began, although elevated antibody levels persisted in two animals for > 12 mo after the first injection. All vaccinated felids were ovariohysterectomized 3-13 mo after vaccination. Folliculogenesis was present in all treated animals, and there was no histopathologic evidence of inflammatory damage to ovaries. Contraceptive efficacy was not specifically evaluated in this study; however, two of the three felids housed with an intact male became pregnant during the study, one of which gave birth to healthy cubs. 相似文献
87.
A 4-year-old, castrated male Maltese developed cranial vena caval thrombosis and chylothorax following central venous catheterization for treatment of postoperative sepsis. Vena caval thrombolysis was attempted using recombinant human tissue-plasminogen activator (t-PA). Thrombolytic therapy led to an acute reduction in the size of the caval thrombus and was followed by prompt resolution of the chylothorax. Hemorrhage at the entry sites of a jugular catheter and esophagostomy tube placed at the time of treatment was a dose-limiting complication of t-PA therapy in this dog. 相似文献
88.
Alexander TW Cook SR Yanke LJ Booker CW Morley PS Read RR Gow SP McAllister TA 《Veterinary microbiology》2008,130(1-2):165-175
The objective of this study was to design a multiplex PCR assay to identify Mannheimia haemolytica, Mannheimia glucosida and Mannheimia ruminalis. The multiplex PCR included primer sets HP, amplifying a DNA region from an unknown hypothetical protein, Lkt and Lkt2, amplifying different regions of the leukotoxinD gene, and 16S to amplify universal bacterial sequences of the 16S rRNA gene. Based on positive amplification, isolates were delineated as M. haemolytica (HP, Lkt, 16S), M. glucosida (HP, Lkt, Lkt2, 16S), or M. ruminalis (HP, 16S). The validity of the assay was examined against 22 reference strains within the family Pasteurellaceae and 17 field isolates (nasal) that had been collected previously from feedlot cattle and tentatively identified as M. haemolytica based on morphology and substrate utilization. Additionally, 200 feedlot cattle were screened for M. haemolytica using multiplex PCR. Forty-four isolates from 25 animals were identified as M. haemolytica. The PCR assay positively identified all M. haemolytica, as confirmed by phenotypic tests and clustering based upon cellular fatty acid methyl ester (FAME) profiles. Selected nasal isolates that exhibited evidence of haemolysis, but were M. haemolytica-negative based on PCR, were also confirmed negative by phenotypic and FAME analyses. The multiplex PCR assay required no additional phenotypic tests for confirmation of M. haemolytica, within the group of bacteria tested. 相似文献
89.
Most fishery independent surveys count, weigh, and measure the majority of species caught. Many surveys also collect selected body structures for in-lab age determinations for selected species. We provide examples from the Northeast Fisheries Science Center's (NEFSC) bottom trawl survey that detail the development of at-sea sampling to elucidate age, growth, maturity, fecundity, spawning season, stomach contents, diet composition, condition, habitat types and prey preferences, basic oceanography (or limnology), and bioenergetics for a suite of diverse species. We show how the development of new methodologies and technologies has decreased both deck-time and time in the lab for processing many of the samples required to provide information on the topics listed above. As new technologies develop to make our trawl catch processing more efficient, we assert that we can notably increase the amount of information collected from trawl surveys with little additional effort. We show that with marginally additional catch processing time on the deck, at-sea sampling can provide a significant return on the knowledge of aquatic and marine resource species, non-resource species, habitats, food webs, and the ecosystems within which they occur. As observing systems continue to expand their remit to provide ecosystem management advice, the need for increased efficiencies on fisheries surveys will remain. 相似文献
90.