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21.
Partial sequencing of the γ-gliadin gene of 62 spelt and 14 soft wheat cultivars was performed. Fifty-six of the 62 spelt cultivars and 13 of the 14 soft wheat cultivars were shown to exhibit the typical spelt or soft wheat γ-gliadin sequence, respectively. Exceptions were ascribed to crossbreeding of soft wheat and spelt. Using the typical soft wheat γ-gliadin sequence, two alternative DNA-based analytical methods were developed for the detection and quantification of spelt flour "adulteration" with soft wheat. A simple and fast detection of soft wheat in spelt flours could be achieved by restriction fragment length (RFLP) analysis. In combination with lab-on-a-chip capillary gel electrophoresis (LOC-CE) the soft wheat proportion could be estimated. Heteroduplex formation served as additional confirmation for the presence of spelt besides soft wheat. Hence, RFLP-LOC-CE constitutes a perfect analysis tool for the quality control of cereal seeds and pure cultivars. A precise quantification of soft wheat "adulterations" in spelt flour down to 1% could be achieved by the developed real-time PCR method. The calibration parameters of the real-time PCR assay fulfilled the minimum performance requirements of the European Network of GMO (genetically modified organisms) Laboratories (ENGL).  相似文献   
22.
Two-year-old bareroot Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco.) seedlings were graded on the basis of four root-volume categories and transplanted to four moisture-stress treatments (6, 12, 18, and 24% soil water content) in pots. Macronutrient concentrations and contents of both old and new foliar tissue were determined. Decreasing soil water content resulted in higher concentrations of phosphorus, potassium, and particularly nitrogen in both old and new foliar tissue. This can be attributed to reduced growth, translocation, metabolic activity, and nutrient requirement in response to moisture stress. Seedlings with relatively higher root volumes exhibited higher nutrient concentrations and contents, as well as increased growth. Thus, increased total root biomass per unit of soil area with increasing seedling root volume may have resulted in greater nutrient use, supply, uptake, and storage.  相似文献   
23.
Rural people in Africa periodically rely on wild fruits to supplement their diet and to generate cash income. However, scientific evidence on the economics of using indigenous fruit tree (IFT) products is scarce. The objective of the study was to fill in some of the gaps for which farm-household surveys were conducted in Zimbabwe during 1999–2000. Gross margins and returns to labour in collection, use and sale of products of Uapaca kirkiana (Muell. Arg., Wild Loquat), Strychnos sp. (S. cocculoides (Baker) and S. spinosa (Lam.), Monkey Orange) and Parinari curatellifolia (Planch. ex. Benth., Fever Tree) were compared with other farming activities. A random sample of over three hundred households in the Murehwa Communal and the Takawira Resettlement Areas was interviewed to gather income and expenditure data. Additionally, income, expenditure and labour allocation of 39 households were closely monitored for one year. Results indicated that the majority of rural households benefited from consumption and sale of indigenous (IF), although the extent varied among households. Within the households, children were the main consumers of fruits. Marketing of IF are carried out by women who used the receipts to purchase household goods. While U. kirkiana fruits were more important in generating cash income than others, fruits of P. curatellifoliawere important for home consumption during periods of food shortages. The gross margins for collection of IFT products were lower than for livestock and crop production. However, returns to labour from collection and use of IFT products were considerably greater than from other activities including gardening and livestock rearing. The study indicates that collection of IFT products is an efficient labour allocation strategy in Zimbabwe. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
24.
OBJECTIVE: To assess the relationship between intake of dietary folate equivalents and risk of myocardial infarction in a German cohort. DESIGN: Intake of dietary folate equivalents was assessed by a validated food-frequency questionnaire. Cox proportional hazard models were used to evaluate the association between intake of dietary folate equivalents and risk of myocardial infarction. SETTING: The European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort, Germany. SUBJECTS: Subjects were 22,245 apparently healthy non-users of vitamin supplements aged 35-64 years. RESULTS: During 4.6 years of follow-up, 129 incident cases of myocardial infarction were identified. Compared with intake below the median (103 microg), higher intake of dietary folate equivalents was associated with a multivariate-adjusted hazard ratio (HR) of 0.57 (95% confidence interval (CI) 0.36-0.91). The inverse association of folate intake and myocardial infarction risk was stronger in participants with an ethanol intake equal to or above the sex-specific median (HR=0.37, 95% CI 0.18-0.79) and attenuated in those with a low ethanol intake (HR=0.67, 95% CI 0.37-1.22). CONCLUSION: An increased intake of dietary folate equivalents was observed to be associated with decreased risk of myocardial infarction in a German study population, pointing towards the importance of folate intake with respect to primary prevention of myocardial infarction.  相似文献   
25.
Fat tissue is the most important energy depot in vertebrates. The release of free fatty acids (FFAs) from stored fat requires the enzymatic activity of lipases. We showed that genetic inactivation of adipose triglyceride lipase (ATGL) in mice increases adipose mass and leads to triacylglycerol deposition in multiple tissues. ATGL-deficient mice accumulated large amounts of lipid in the heart, causing cardiac dysfunction and premature death. Defective cold adaptation indicated that the enzyme provides FFAs to fuel thermogenesis. The reduced availability of ATGL-derived FFAs leads to increased glucose use, increased glucose tolerance, and increased insulin sensitivity. These results indicate that ATGL is rate limiting in the catabolism of cellular fat depots and plays an important role in energy homeostasis.  相似文献   
26.
Drought is one of the crucial factors limiting plant growth and is expected to become even more limiting in many regions as the effects of climate change increase. Knowledge of genetic adaptation to environmental factors can help develop strategies for successful reforestation in arid terrain. In this study, Austrian pine (Pinus nigra Arnold) seedlings grown from seed collected from 40 open-pollinated families from five Balkan Peninsula provenances were evaluated for survival and growth under imposed drought. Within each provenance, seed was collected from an extremely harsh habitat and from a favorable habitat. One-year-old seedlings, from each provenance, habitat type and open pollinated family were transplanted into three “stressbeds”, each designed to simulate different levels of water availability by filling with varying ratios of crushed stone and soil. Seedling height growth and survival were recorded every 20–30?days from April–September. In all provenances, seedlings grown from seed originating from the harsh habitats had lower survival regardless of stressbed treatment compared to those grown from seed collected from favorable habitats, with the exception of one population from the Vi?egrad provenance which had high survival rates throughout. Overall height growth was very low and did not follow consistent patterns among treatment groups. Cluster analyses of survival data showed that populations from a similar habitat generally grouped together, regardless of provenance. The lowest and highest survival values were found in seedlings from harsh habitats, while those from the favorable habitats clustered in the mid-range. These results suggest that higher seed quality from productive stands may be the most influential factor determining seedling vigor under drought stress and that genetic adaptation to drought was not detected in adjacent populations having different habitat conditions.  相似文献   
27.
A total of 413 pig faecal samples were collected from pre-weaners (119), starters (131), pre-growers (123) and sows (40) from a farm with a closed breeding system segmented into two breeding complexes and a growing complex in the region of Vysočina, Czech Republic and screened for the presence of Cryptosporidium using staining methods and genotyping (SSU rRNA). Cryptosporidium oocysts were detected by microscopy in the faeces of 21.1% of the samples (87/413). Sequence analyses and RFLP identified C. suis in 44, Cryptosporidium pig genotype II in 23 and C. muris in 2 samples. No mixed infections were found.Pigs under 7 weeks of age were infected with C. suis only. Cryptosporidium pig genotype II was found in animals from 7 weeks of age. No relationship was found between diarrhoea and any Cryptosporidium infection in any of the different age groups (P < 0.05). The pre-weaned pigs shed significantly more Cryptosporidium oocysts than older pigs and it was associated with C. suis infection.  相似文献   
28.
Not much is known about IBDV-pathogenesis and immune mechanisms following in ovo vaccination. In this study, we compared the immunopathogenesis of an intermediate IBDV-vaccine in post-hatch- and in ovo-inoculated chickens. In ovo-vaccinated birds recovered significantly faster from lesions of the bursa of Fabricius than post-hatch vaccinated (P<0.05). A significant accumulation of intrabursal CD8(+) T cells was observed in post-hatch but not in in ovo-vaccinated chickens (P<0.05). The innate immunity was comparable between in ovo- and post-hatch-vaccinated groups as indicated by comparable intrabursal macrophage accumulation and intrabursal IBDV-clearance. Overall, our observations indicate that IBDV in ovo vaccination may be advantageous over post-hatch. In ovo-vaccinated birds recover faster from bursa lesions and exhibit similar protection against challenge in comparison to post-hatch vaccinated.  相似文献   
29.
The clinical course of inflammatory bowel disease (IBD) in dogs is characterized by spontaneous exacerbations and remissions, which makes assessment of disease burden difficult. The objectives of this study were to develop a scoring system for evaluation of canine IBD activity and to validate this scoring method by correlating it to objective laboratory and histologic indices of intestinal inflammation. Fifty-eight dogs with IBD were evaluated prospectively and compared to 9 disease-free control dogs. Clinical disease activity was quantified by a simple scoring system, the canine IBD activity index (CIBDAI), and compared to serum concentrations of C-reactive protein (CRP), haptoglobin (HAP), alpha-acid glycoprotein (AGP), and serum amyloid A (SAA), as well as histology scores derived from endoscopic biopsy specimens. Forty-six dogs were available for a reevaluation of the CIBDAI, CRP HAP, and AGP, and 34 dogs had repeat analysis of SAA performed after medical therapy. Serum concentrations of CRP were significantly (P < .02) increased in dogs with CIBDAI scores > or = 5 (mild disease activity or greater) compared to controls. Among IBD dogs, the CIBDAI showed good correlation (r = 0.82, P < .0001) to both histology and HAP scores, but CRP also was a strong co-correlate of disease activity. The IBD dogs showed significantly (P < .0001) decreased CIBDAI and CRP values but significantly (P < .0001) increased HAP concentrations after medical therapy compared to pretreatment values. We conclude that the CIBDAI is a reliable measure of inflammatory activity in canine IBD and that CRP is suitable for laboratory evaluation of the effect of therapy in these patients.  相似文献   
30.
Experimental reproduction of necrotising enteritis of sucking pigs was successfully achieved by using both Clostridium perfringens Type C strains, which had been isolated from sucking pigs with necrotising enteritis, and Type C strain 3628 of A.T.C.C. (sub-type C1). The lethal dose for sucking pigs was between 20 X 10(6) and 12 X 10(7) pathogens per animal. The disease could not even be induced by repeated application of no-bacterial toxin of Cl. perfringens Type C nor by administration of Cl. perfringens Type A strains which had been cultured from broilers with necrotising enteritis. Necrotising enteritis was found to develop in two phases in sucking pigs. First, the pathogen will deposit to the villous epithelium and then penetrate the superficial strata of the mocous membrane. In the second phase, the villous structure will be destroyed by the lethal, haemolysing, and necrotising toxins of Cl. perfringens. The role played by individual toxin fractions is discussed together with the importance of humoral and localised infection defence. Sucking pigs may be sufficiently protected against infection based on single or ten-fold lethal infectious dosage by two vaccinations of the mother animal, five and three weeks prior to parturition, using "Enterotoxaemia Vaccine Dessau bivalent". Infection then would not occur unless a hundredfold lethal dose was applied. Characteristics include diarrhoea, apathy, exhaustion, and death.  相似文献   
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