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11.
Journal of Soils and Sediments - Humic acids (HA) have several environmental roles, but are particularly important in aquatic environments, being recognized as redox active natural organic matter...  相似文献   
12.
Prolonged exposure to captive conditions has led to the development of a rainbow trout ‘farmed’ phenotype, which is different from that of wild trout. Selection for desirable productive traits in hatcheries has resulted in the development of some morphological traits that are maladaptive in nature. The recent development of organic aquaculture, guided by the well‐being of the fish, could potentially produce a new farmed phenotype that would be more adaptive in nature. In this study, rainbow trout reared in intensive and organic farms were compared by means of shape analysis, to detect patterns of shape variation associated with rearing environment. The results of this study highlight a significant effect of the rearing method on rainbow trout shape: organically reared trout showed a higher body profile, in particular in the head and trunk regions, shorter median fins and a deeper caudal peduncle. A combined effect of density and habitat complexity could have contributed to the observed shape differences: in organic rearing systems, lower densities and steady water could increase territoriality and aggressive interactions, promoting body designs more functional in rapid attacks and escapes.  相似文献   
13.
A hydroxyapatite orbital implant was used after enucleation of an eye from a 5-year-old performance horse. A custom-made corneoscleral prosthesis was made and fitted over the hydroxyapatite implant. The implant and surgery were well tolerated. Placement of a cosmetic prosthesis is desired after enucleation of equine eyes to allow horses to return to competition. Synthetic spheres consisting of methylmethacrylate or silicone have been used, although reported complications have included extrusion, infection, and poor cosmetic results. Hydroxyapatite orbital implants made from marine coral allow vascular and fibrous tissue growth from the host orbit into the implant, which decreases the possibility of implant extrusion or infection and allows enhanced healing of defects in the overlying conjunctiva. Extraocular muscle fixation onto the implant permits motility and assists in the prevention of implant extrusion.  相似文献   
14.
15.
The objective of the present study was to determine the efficiency of blood neutrophils (PMN) taken from sheep during acute stress. Ten healthy Charolle sheep were sampled before treatment (T0) and 1 (T1), 2 (T2), 24 (T24) and 48 (T48) hours after 1-24ACTH administration. Ten sheep serving as the controls were sampled at the same time intervals, using saline solution instead of 1-24ACTH. At each time sampling, rectal temperature, heart rate, cortisol, glucose, non-esterified fatty acids (NEFA), total and differential leukocyte counts were evaluated. PMN were isolated after centrifugation of whole blood and hypotonic lysis of RBC. Chemotaxis was evaluated on a modified Boyden chamber using a nitrate cellulose filter and both Zymosan activated serum (ZAS) and interleukin-8 (IL-8) as chemoattractants. Phagocytosis was measured using both non-opsonized latex beads and fluoresceinated yeasts opsonized with homologous serum. Superoxide (O(-)2) production was evaluated by measuring superoxide dismutase-inhibitable reduction of ferricytochrome C, and adherence by a colorimetric assay of acid phosphatase activity of adherent cells. The administration of 1-24ACTH induced an acute stress reaction, indicated by the presence of clinical, biochemical and hematological changes. Adherence significantly increased from T0 to T2 in treated sheep. This might be responsible for the depression of non-specific immunity in stressed animals. Studies using stressors other than 1-24 ACTH are needed to verify the influence of other components of the stress reaction on PMN functions.  相似文献   
16.
A case of leishmaniosis in domestic cats (Felis catus domesticus) is described. The subject showed a nodular lesion on the eyelid. The diagnosis was achieved by serological, parasitological, and light and electron microscopic investigations. By molecular techniques the aetiological agent was identified as belonging to Leishmania infantum, the species implicated in human and canine leishmaniosis in southern Europe. A preliminary study on the prevalence of asymptomatic feline leishmaniosis, performed in the areas where the infected cat was identified, revealed a low seroprevalence of infection: only 1 (0.9%) of the 110 cat sera examined by indirect fluorescent antibody test was positive for anti-Leishmania antibodies. Because clinical signs in feline leishmaniosis are unspecific and similar to those observed in other diseases commonly found in this species, leishmaniosis must be added to the differential diagnosis by feline veterinary practitioners and adequate serologic and histopathologic investigations must be performed in endemic areas.  相似文献   
17.
A cpDNA fragment of 34 genotypes belonging to Citrus and four related genera was amplified and sequenced. Chloroplast microsatellites were revealed with the length of repeats ranging from 25 to 44 bases. Other than the normal uninucleotide poly(A) repeats, a trinucleotide poly(TAA) motif was also found, the first report of such repeats in a plant chloroplast genome. According to SSR structure variations, 18 Chloroplast SSR Types (CST) were identified. The CST sequences were informative for better understanding the genetic relationships of chloroplast genomes among the analyzed genotypes and confirmed some previous hypotheses about the female parent of several hybrid accessions.  相似文献   
18.
Mancuso S 《Tree physiology》1999,19(2):95-101
Electrical impedance parameters were measured in shoots and leaves of Olea europaea L. for 18 months to determine seasonal variations in intracellular and extracellular resistances and in the state of membranes; these factors were related to rooting ability. Double- and single-DCE (ZARC) models were used as equivalent circuits for shoots and leaves, respectively. Seasonal variations were observed in all of the impedance parameters measured. Intracellular resistance of the shoots increased during the winter resting period, whereas intracellular resistance of the leaves decreased. Relaxation times for both leaves and shoots decreased during the winter. Close relationships were found between rooting ability and intracellular and extracellular resistances and relaxation times of shoots and leaves.  相似文献   
19.
Biofilm-forming ability is increasingly being recognized as an important virulence factor in several Staphylococcus species. This study evaluated the biofilm-forming ability of sixty canine derived clinical isolates of S. pseudintermedius, using three phenotypic methods, microtiter plate test (MtP), Congo red agar method (CRA) and tube adherence test, and the presence and impact of biofilm-associated genes (icaA and icaD). The results showed that icaA and icaD genes were detected concomitantly in 55 (91.7%) of 60 isolates. A majority (88.3%) of the strains screened had matching results by the tube adherence test, MtP and PCR analysis. Better agreement (95%) was found between the PCR-based analysis and the CRA. Results of the icaA and icaD gene PCRs showed good agreement with CRA results, with a kappa of 0.7. Comparing the phenotypic methods, the statistical analysis showed that the agreement among the phenotypical tests using categorical data was generally good. Considering two classes (biofilm producer and biofilm non-producer), the percentage of matching results between the CRA method and the tube adherence test and between the CRA method and the MtP was 93.3%. A concordance of 100% was revealed between the MtP and the tube adherence test. The results indicate a high prevalence of the ica genes within S. pseudintermedius isolates, and their presence is associated with in vitro formation of a biofilm. A combination of phenotypic and genotypic tests is recommended for investigating biofilm formation in S. pseudintermedius.  相似文献   
20.
PCR products obtained by selective amplification of transgenic DNA derived from food samples containing Roundup Ready soybean or Bt-176 maize have been analyzed by anion-exchange HPLC. Peptide nucleic acids (PNAs), oligonucleotide analogues known to bind to complementary single-stranded DNA with high affinity and specificity, have been used as specific probes in order to assess the identity of the peaks observed. Two different protocols were adopted in order to obtain single-stranded DNA: amplification with an excess of one primer or digestion of one DNA strand. The single-stranded DNA was mixed with the PNA probe, and the presence of a specific sequence was revealed through detection of the corresponding PNA:DNA peak with significantly different retention time. Advantages and limits of this approach are discussed. The method was tested with reference materials and subsequently applied to commercial samples.  相似文献   
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