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41.
Archer SL Greenlund KJ Valdez R Casper ML Rith-Najarian S Croft JB 《Public health nutrition》2004,7(8):1025-1032
OBJECTIVE: To examine differences in food habits among Native Americans with and without diabetes. DESIGN: A cross-sectional epidemiological study in which participants underwent a physical examination and answered an extensive interviewer-administered questionnaire to assess differences in food servings, preparation and eating habits. SETTING/PARTICIPANTS: Participants aged >/=25 years were randomly selected from three reservations in Minnesota and Wisconsin. There were 990 persons without diabetes, 294 with a prior diagnosis of diabetes, and 80 with fasting glucose >125 mg dl(-1) but no prior diabetes diagnosis. RESULTS: Persons with prior diabetes diagnosis were less likely than those without diabetes to report eating fast-food meals two or more times per week, eat visible fat on meat or the skin on poultry, eat fried chicken or fried fish, to add fat to cooked vegetables and drink whole milk. Persons with previously undiagnosed diabetes were more likely than previously diagnosed persons to report eating fast-food meals two or more times per week, eat visible fat on meat and the skin on poultry, drink whole milk and eat fried fish, but were less likely to drink low-fat milk. Previously undiagnosed persons were more likely than either diagnosed persons or persons without diabetes to consume lard from cooked foods and use it when cooking. CONCLUSION: Persons with diagnosed diabetes showed healthier eating patterns than those without diabetes, while undiagnosed persons showed some less favourable patterns. Because virtually all persons with diabetes in these communities receive nutrition education, the results suggest that nutrition education programmes for diabetics may be associated with healthier eating patterns. 相似文献
42.
Reginald A Valdez Matthew J Rock Anne K Anderson Katherine I O'Rourke 《Journal of veterinary diagnostic investigation》2003,15(2):157-162
Formalin-fixed, paraffin-embedded tissue sections from a 3-year-old female Angora goat suffering from clinical scrapie were immunostained after hydrated autoclaving using a monoclonal antibody (mAb, F99/97.6.1; IgG1) specific for a conserved epitope on the prion protein. Widespread and prominent deposition of the scrapie isoform of the prion protein (PrPSc) was observed in the brain, brainstem, spinal cord, retina, postganglionic neurons associated with parasympathetic ganglia of myenteric and submucosal plexuses, Peyer's patches, peripheral lymph nodes, and pharyngeal and palatine tonsils. The goat was homozygous for PrP alleles encoding 5 octapeptide repeat sequences in the N-terminal region of the prion protein and isoleucine at codon 142, a genotype associated with high susceptibility and short incubation times in goats. The results of this study indicate that mAb F99/97.6.1 is useful for detection of PrPSc deposition, and this is a specific and reliable immunohistochemical adjunct to histopathology for diagnosis of natural caprine scrapie, although precise determination of the diagnostic sensitivity and specificity of the assay as a diagnostic test for scrapie in goats will require examination of a sufficiently large sample size. As with ovine scrapie, prion protein is widely distributed in the central and peripheral nervous systems, gastrointestinal tract, and lymphoid tissues in natural caprine scrapie. 相似文献
43.
44.
W L Goff W C Johnson S M Parish G M Barrington T H Elsasser W C Davis R A Valdez 《Veterinary immunology and immunopathology》2002,84(3-4):237-251
The requirement for IFN-gamma and/or TNF-alpha as co-stimulants with Babesia bovis merozoites for nitric oxide (NO) production was examined, as well as the regulatory role of IL-4 and IL-10. Purified B. bovis merozoites did not induce the production of NO in undifferentiated monocytes without addition of exogenous IFN-gamma and TNF-alpha unless the monocytes taken ex vivo were producing TNF-alpha endogenously. Under the latter condition, the NO production resulting from merozoite stimulation remained IFN-gamma-dependent. There was no evidence for endogenous synthesis of TNF-alpha in monocyte-derived macrophages (MDM), and merozoites alone were incapable of inducing TNF-alpha mRNA in MDM. However, while merozoites plus IFN-gamma induced TNF-alpha mRNA expression in MDM, NO was not produced. Both IL-4 and IL-10 inhibited expression of iNOS and production of NO in merozoite-stimulated monocytes. 相似文献
45.
Malik FI Hartman JJ Elias KA Morgan BP Rodriguez H Brejc K Anderson RL Sueoka SH Lee KH Finer JT Sakowicz R Baliga R Cox DR Garard M Godinez G Kawas R Kraynack E Lenzi D Lu PP Muci A Niu C Qian X Pierce DW Pokrovskii M Suehiro I Sylvester S Tochimoto T Valdez C Wang W Katori T Kass DA Shen YT Vatner SF Morgans DJ 《Science (New York, N.Y.)》2011,331(6023):1439-1443
Decreased cardiac contractility is a central feature of systolic heart failure. Existing drugs increase cardiac contractility indirectly through signaling cascades but are limited by their mechanism-related adverse effects. To avoid these limitations, we previously developed omecamtiv mecarbil, a small-molecule, direct activator of cardiac myosin. Here, we show that it binds to the myosin catalytic domain and operates by an allosteric mechanism to increase the transition rate of myosin into the strongly actin-bound force-generating state. Paradoxically, it inhibits adenosine 5'-triphosphate turnover in the absence of actin, which suggests that it stabilizes an actin-bound conformation of myosin. In animal models, omecamtiv mecarbil increases cardiac function by increasing the duration of ejection without changing the rates of contraction. Cardiac myosin activation may provide a new therapeutic approach for systolic heart failure. 相似文献
46.
PC Rodriguez LB Valdez T Zaobornyj A Boveris MT Beconi 《Reproduction in domestic animals》2011,46(1):74-81
The aim of this work was to quantify NO, O2? and ONOO? production during heparin‐induced capacitation of cryopreserved bovine spermatozoa. A time dependent hyperbolic increase was observed for heparin‐dependent capacitation, O2 uptake, and NO production. Conversely, O2? production was increased during the first 15 min of incubation, showing a decrease from this time until 45 min. At 15 min of heparin incubation, a threefold increase in O2 consumption (5.9 ± 0.6 nmol/min × 107 cells), an enhancement in NO release (1.1 ± 0.2 nmol/min × 107 cells), and a five‐fold increase in O2? production (1.3 ± 0.07 nmol/min × 107 cells), were observed. Peroxynitrite production rate was estimated taking into account NO and O2? generation and the second‐order rate constant of the reaction between these species. To conclude, heparin‐induced capacitation of cryopreserved bovine spermatozoa activates (i) mitochondrial O2 uptake by high ADP levels due to increased energy requirements, (ii) NO production by a constitutive NOS and (iii) O2? production by a membrane‐bound NAD(P)H oxidase. The products of both enzymes are released to the extracellular space and could be involved in the process of sperm capacitation. 相似文献
47.
FA Street-Perrott Y Huang RA Perrott G Eglinton P Barker LB Khelifa DD Harkness DO Olago 《Science (New York, N.Y.)》1997,278(5342):1422-1426
Carbon-isotope values of bulk organic matter from high-altitude lakes on Mount Kenya and Mount Elgon, East Africa, were 10 to 14 per mil higher during glacial times than they are today. Compound-specific isotope analyses of leaf waxes and algal biomarkers show that organisms possessing CO2-concentrating mechanisms, including C4 grasses and freshwater algae, were primarily responsible for this large increase. Carbon limitation due to lower ambient CO2 partial pressures had a significant impact on the distribution of forest on the tropical mountains, in addition to climate. Hence, tree line elevation should not be used to infer palaeotemperatures. 相似文献
48.
Kaya L. Klop-Toker Jose W. Valdez Michelle P. Stockwell Loren Fardell Simon Clulow John Clulow Michael J. Mahony 《水产资源保护:海洋与淡水生态系统》2021,31(10):2788-2803
- As the proportion of threatened species increases, so too does the need for effective conservation strategies. In response, captive breed-and-release and habitat mitigation programmes are two conservation actions that are increasing in use and effectiveness.
- Success of these programmes is frequently hampered by the continued presence of threatening processes. In the case of amphibian reintroductions, a key threatening process that is difficult to eliminate is the deadly fungal pathogen, Batrachochytrium dendrobatidis (Bd). This pathogen is the proximate cause of decline for the threatened green and golden bell frog, Litoria aurea, and has contributed to the failure of previous breed-and-release programmes of this amphibian.
- To investigate whether is it possible to establish a captive-bred population of L. aurea that could persist in the presence of Bd, a breed-and-release programme was conducted in a created habitat that included increased salinity to inhibit fungal growth rates, exclusion of potential reservoir hosts and source animals bred from parents ‘experienced’ with the strain of Bd present in the release environment.
- The population persisted in the created habitat for more than 4 years (the timescale of monitoring) but suffered higher infection levels compared with nearby extant populations of L. aurea. These infections significantly reduced apparent survival. Infection dynamics were linked to temperature, host density in the previous season, and size and age of the host, and these factors differed from those in extant populations and are likely to have contributed to the high levels of Bd infection at the created site.
- This article discusses how it may be possible to manipulate these factors to improve the success of future breed-and-release programmes, and recommends the construction of warm water bodies and a strategy of prioritizing the release of fewer, large propagules of high body condition and mixed-age class, over large numbers of younger, smaller animals.
49.
Cristian Ugaz Ricardo A. Valdez Marta C. Romano Francisco Galindo 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(4):285-290
Few studies have been carried out on the welfare of captive bottlenose dolphins (Tursiops truncatus). Of these, most include information on animals kept in closed facilities or pools. The aim of this study was to assess the welfare of captive bottlenose dolphins in open and closed facilities by measuring states of individual behavior and salivary cortisol concentrations. A total of 23 bottlenose dolphins were studied in 4 different dolphinaria. Dolphinaria A and B have closed facilities, whereas dolphinaria C and D have open facilities. A total of 152 hours of behavioral observations were analyzed using a combination of behavior and scan sampling to obtain information on individual time budgets. Salivary cortisol concentrations were measured using radioimmunoassay in 96 and 180 saliva samples of dolphins kept in closed and open facilities, respectively. In general, the results found that dolphins kept in open facilities spent less time floating (P < 0.05) and swimming in circular patterns than linear ones (P < 0.05) compared with dolphins in closed facilities. Dolphins kept in open facilities also had lower salivary cortisol concentrations than dolphins kept in closed facilities (P < 0.05). For this reason, we suggest that further research should include other welfare indicators such as reproductive function and health measurements to know more about the relationships between the design of pools and dolphin welfare. 相似文献
50.
Chandra Prakash Kala Yogesh Dubey Suharyanto Mine Nose Susumu Shiraishi Hai-hua Zhang Guang-yu Li Xiu-mei Xing Er-jun Ren Ying Yang Fu-he Yang Subhash Hathurusingha Nanjappa Ashwath Ya-ni Gao Cheng-rui Tian Li-li Zhao Assan Gnoumou Fidèle Bognounou Karen Hahn Adjima Thiombiano S. M. Sirajul Haque Rahima Ferdoshi Sohag Miah M. Nural Anwar Angel Rolando Endara Agramont Sergio Franco Maass Gabino Nava Bernal Juan Ignacio Valdez Hernández Todd S. Fredericksen 《林业研究》2012,23(1):173-173