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A population genetic analysis based on eight genomic SSR markers and three EST-SSR (expressed sequence tags) markers developed in peach (Prunus persica (L.) Batsch) and Japanese plum (Prunus salicina Lindl.) was carried out in 12 wild populations of cherry plum (Prunus divaricata Ledeb.) sampled along the Iranian coast of the Caspian Sea. A total of 184 alleles (3–31 per locus) were detected with a mean value of 16.7 alleles per locus. None of the loci or populations showed deviation from Hardy–Weinberg equilibrium, and all markers proved to be unlinked. The mean values for the observed and the expected heterozygosity were 0.66 and 0.73, respectively. There was very little genetic differentiation among populations, as was indicated by low overall values of Wright’s FST (0.03) and Nei’s GST (0.08). An analysis of molecular variance (AMOVA) showed that 96.8% of the total variance was attributable to differences between individuals within populations. Genetic and geographic distances were nevertheless positively correlated, as evidenced by a Mantel test. The high level of genetic diversity and the apparent lack of genetic structure in wild P. divaricata may be attributed to frequent long distance gene flow through frugivorous birds and possibly humans, as has been documented for other Prunus species.  相似文献   
53.
The effect of an additive preservative solution on canine red blood cell posttransfusion viability (PTV) and on selected canine red blood cell biochemical parameters was studied. One unit (450 mL) of blood was collected from 6 clinically normal dogs into the anticoagulant citrate phosphate dextrose, centrifuged, and the plasma removed. The red blood cells were then suspended in 100 mL of a saline, adenine, dextrose, and mannitol solution and stored at 4°C. Aliquots were removed for study at 1, 10, 20, 30, 37, and 44 days. The 24-hour PTV of autologous red blood cells was determined using a sodium chromate (61Cr) label. Red blood cell concentrations of 2,3-diphosphoglycerate (2,3-DPG), adenosine-5'-triphosphate (ATP), and pH were also determined. Canine red blood cell PTV, pH, ATP, and 2,3-DPG concentrations decreased during storage ( P < .05). The PTV decreased from 94% using day 1 red blood cells to 80% and 75% using day 37 and day 44 red blood cells, respectively ( P < .05). Although the mean PTV of the day 44 stored units equaled the Food and Drug Administration (FDA) minimum standard for human red blood cells, the PTV was substandard in 75% of the day 44 units. The FDA standard was exceeded in 83% of the day 37 units. It was concluded that 37-day-old canine red blood cells preserved with a saline, adenine, dextrose, and mannitol solution are of acceptable quality for transfusion.  相似文献   
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The acute phase protein orosomucoid (ORM) has anti-inflammatory and immunomodulatory effects, and may play an important role in the maintenance of metabolic homeostasis in obesity-induced low-grade inflammation. Even though the pig is a widely used model for obesity related metabolic symptoms, the expression of ORM has not yet been characterized in such pig models. The objective of this study was to investigate the expression of ORM1 mRNA in liver, visceral adipose tissue, subcutaneous adipose tissue (SAT) from the abdomen or retroperitoneal abdominal adipose tissue (RPAT) and SAT from the neck, as well as the serum concentration of ORM protein in three porcine obesity models; the domestic pig, Göttingen minipigs and Ossabaw minipigs.No changes in ORM1 mRNA expression were observed in obese pigs compared to lean pigs in the four types of tissues. However, obese Ossabaw minipigs, but none of the other breeds, showed significantly elevated ORM serum concentrations compared to their lean counterparts. Studies in humans have shown that the expression of ORM was unchanged in adipose tissue depots in obese humans with an increased serum concentration of ORM. Thus in this respect, obese Ossabaw minipigs behave more similarly to obese humans than the other two pig breeds investigated.  相似文献   
56.
Increasingly large numbers of poultry are held in production systems with access to outdoor areas. In these systems intestinal helminths are found with flock prevalences of up to 100%. Helminth infections influence chicken health negatively, which is why the following investigation has been performed.In the present experiment, 20 chickens of two inbred chicken lines containing the major histocompatibility complex (MHC) haplotypes, B14 and R5, were inoculated with 500 embryonated Ascaridia galli eggs. The A. galli-specific IgG titres of serum samples and the excretion of A. galli eggs in chicken faeces were measured for a period of 81 weeks.The level of excreted A. galli eggs measured as eggs per gram chicken faeces (EPG) varied greatly between chickens in each line. Significant differences were found between the two lines and with the R5 chickens reaching the highest levels. Likewise, the A. galli-specific IgG titres in serum differed significantly between the two lines, and an inverse relationship between infection level (EPG) and antibody titres was found. Although this inverse relationship suggests that humoral immunity may be involved in protection against A. galli infection, the high antibody titres did not prevent continued infection.  相似文献   
57.
We conducted a screening campaign to investigate fungi as a source for new antimalarial compounds. A subset of our fungal collection comprising Chinese mangrove endophytes provided over 5000 lipophilic extracts. We developed an accelerated discovery program based on small-scale cultivation for crude extract screening and a high-throughput malaria assay. Criteria for hits were developed and high priority hits were subjected to scale-up cultivation. Extracts from large scale cultivation were fractionated and these fractions subjected to both in vitro malaria and cytotoxicity screening. Criteria for advancing fractions to purification were developed, including the introduction of a selectivity index and by dereplication of known metabolites. From the Chinese mangrove endophytes, four new compounds (14–16, 18) were isolated including a new dimeric tetrahydroxanthone, dicerandrol D (14), which was found to display the most favorable bioactivity profile.  相似文献   
58.
During rice milling, the bran and germ are successively removed from the caryopsis (kernel). Because bran and germ contain large quantities of lipid, the amount of lipid remaining on the kernel surface may be used as a method for the assessment of milling quality. Bulk samples of rice pureline varieties and an experimental hybrid were milled for 0, 10, 20, 30, and 40 s. Scanning electron microscopy (SEM) revealed that brown rice kernels had large contours of linear protuberances and depressions running lengthwise along the kernel surface. The protuberances were abraded successively during milling, but varying amounts of material remained in the depressions. Light microscopy combined with the lipid-specific probes Nile Blue A or Sudan Black B demonstrated that the material in the depressions observed with SEM was lipid. Sections of whole, milled rice kernels, prepared using a modified sectioning technique and stained with Nile Blue A, showed that portions of the embryo remain after milling and that lipid is located on or near the surface of the kernel. Differences in quantity and distribution of residual lipid as milling duration increased were documented photographically to indicate the extent to which the bran and embryo components were removed during milling. This paper provides proof of concept that residual lipid is a robust measure of the degree of milling.  相似文献   
59.
The high viscosity of vegetable oil can be reduced by transesterification with alcohols and converting it into biodiesel. Biodiesel can be used neat or blended with diesel as engine fuel. This study demonstrates that esters of castor oils have a higher viscosity than safflower oil derived esters and the viscosity can be reduced by blending with diesel. The viscosity increased in a non-linear fashion as the percentage of castor esters increased in castor esters diesel blends and in castor esters safflower esters blends. Only slight increases in viscosity were observed for B40 and B60 mixtures with No. 2 diesel. Addition of ten chemical additives in castor esters at the rate of 0.01%, 0.1% and 1.0% showed limited viscosity reduction.  相似文献   
60.
Twenty-four female BALB/c mice were orally inoculated with 10(8) CFU Escherichia coli ATCC 25922 and euthanized 2.5, 7, 13 and 25 h post-inoculation. The levels of organ nitric oxide (NO) and plasma endotoxin, TNF-alpha and nitrite/nitrate (NO(x)) were compared to those found in sham-inoculated mice, to evaluate systemic host-response to a low-level oral exposure to Gram-negative bacteria. Organ bacterial culture and immunohistochemistry for iNOS were performed on lungs, liver, kidneys and brain from all mice. Organ NO and plasma TNF-alpha levels were higher in E. coli-inoculated animals, but no differences were detected in plasma endotoxin levels, NO(x) or iNOS immunostaining for any of the animal groups. Single oral gavage with live E. coli stimulates an early systemic immune response in clinically healthy mice as evidenced by increased plasma TNF-alpha and organ NO levels, but bacteremia and endotoxemia are not related to this inflammatory response.  相似文献   
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