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21.
Prunus avium is primarily cultivated for its fruit, sweet cherries. However, it is also used to produce high‐quality timber. In a P. avium seed orchard, gametophytic self‐incompatibility is a restriction for free pollen flow and should be considered when establishing basic forest materials. In this study, S‐locus diversity and cross‐incompatibility of wild cherry individuals in clonal banks established for breeding for timber production were investigated. Wild cherry trees (140) with outstanding forest growth habit, collected in northern Spain, grafted and planted in two clonal banks, were genotyped at the S‐locus. The self‐incompatibility S‐locus genes, S‐RNase and SFB, were analysed by PCR. Twenty‐two S‐haplotypes, resulting in 72 different S‐genotypes, were identified. The genotypes were grouped into 33 incompatibility groups and 39 unique genotypes. This initial S‐locus analysis revealed large genetic diversity of wild cherry trees from the Spanish northern deciduous forest, and provides useful information for seed orchard design. Wild P. avium displays significantly more genetic diversity than what is detected in local cultivars, revealing a narrowing of genetic diversity during local domestication.  相似文献   
22.

Background

Salinity is one of the most severe and widespread abiotic stresses that affect rice production. The identification of major-effect quantitative trait loci (QTLs) for traits related to salinity tolerance and understanding of QTL × environment interactions (QEIs) can help in more precise and faster development of salinity-tolerant rice varieties through marker-assisted breeding. Recombinant inbred lines (RILs) derived from IR29/Hasawi (a novel source of salinity) were screened for salinity tolerance in the IRRI phytotron in the Philippines (E1) and in two other diverse environments in Senegal (E2) and Tanzania (E3). QTLs were mapped for traits related to salinity tolerance at the seedling stage.

Results

The RILs were genotyped using 194 polymorphic SNPs (single nucleotide polymorphisms). After removing segregation distortion markers (SDM), a total of 145 and 135 SNPs were used to construct a genetic linkage map with a length of 1655 and 1662 cM, with an average marker density of 11.4 cM in E1 and 12.3 cM in E2 and E3, respectively. A total of 34 QTLs were identified on 10 chromosomes for five traits using ICIM-ADD and segregation distortion locus (SDL) mapping (IM-ADD) under salinity stress across environments. Eight major genomic regions on chromosome 1 between 170 and 175 cM (qSES1.3, qSES1.4, qSL1.2, qSL1.3, qRL1.1, qRL1.2, qFWsht1.2, qDWsht1.2), chromosome 4 at 32 cM (qSES4.1, qFWsht4.2, qDWsht4.2), chromosome 6 at 115 cM (qFWsht6.1, qDWsht6.1), chromosome 8 at 105 cM (qFWsht8.1, qDWsht8.1), and chromosome 12 at 78 cM (qFWsht12.1, qDWsht12.1) have co-localized QTLs for the multiple traits that might be governing seedling stage salinity tolerance through multiple traits in different phenotyping environments, thus suggesting these as hot spots for tolerance of salinity. Forty-nine and 30 significant pair-wise epistatic interactions were detected between QTL-linked and QTL-unlinked regions using single-environment and multi-environment analyses.

Conclusions

The identification of genomic regions for salinity tolerance in the RILs showed that Hasawi possesses alleles that are novel for salinity tolerance. The common regions for the multiple QTLs across environments as co-localized regions on chromosomes 1, 4, 6, 8, and 12 could be due to linkage or pleiotropic effect, which might be helpful for multiple QTL introgression for marker-assisted breeding programs to improve the salinity tolerance of adaptive and popular but otherwise salinity-sensitive rice varieties.
  相似文献   
23.
The impact of detritivorous earthworms (Eisenia andrei) on microbial community structure and function in grape marc, a lignocellulosic enriched plant residue, was investigated in a mesocosm experiment. Analysis of carbon and nitrogen pools was also carried out in order to evaluate how changes in microbial communities affect plant residue decomposition. The grape marc was completely processed after fifteen days as a result of the high density of earthworms present and the rapid gut transit time. Eisenia andrei had a large impact on the structure of the microbial community, as revealed by phospholipid fatty acid analysis. Earthworm activity reduced the abundance of both bacterial (except for Gram-negative bacteria) and fungal PLFA biomarkers relative to the control values. Decreases in microbial activity and in protease and cellulase activities were also attributable to the presence of earthworms. Moreover, earthworms strongly modified the substrate utilization patterns of microbial communities, as revealed by BIOLOG analysis. The presence of earthworms led to an increase in the utilization of some amino acids and polymers, which reached a higher substrate diversity value than that in the control mesocosm. The differences in microbial communities were accompanied by a reduction in the total C content and the labile C pool, relative to the control, although there were no significant differences in either cellulose or hemicellulose contents. However, total N content increased in both mesocosms – with and without earthworms – and the concentration of NH4+ was also enhanced by earthworm activity. The results indicate that detritivorous earthworms play a key role in decomposing fresh plant residues in the short term via their intensive interactions with microbial communities.  相似文献   
24.
The macroscopic and microscopic features of a retroperitoneal perirenal pseudocyst in a 12-month-old ram without impairment of renal function are described. In humans and animals, uriniferous pseudocysts may be of traumatic origin, resulting from rupture of kidney, renal pelvis, or ureter, or congenital. Lymphatic pseudocysts may develop secondary to inflammatory obstruction of the hilar lymphatics after perinephritis or renal transplantation. In this case, histologic characteristics of the pseudocyst wall were suggestive of development from the parietal peritoneal layer encapsulating the kidney. This is the first case of retroperitoneal perirenal pseudocyst in a sheep.  相似文献   
25.
The biological activity of a series of N-(pyrid-3-yl)thioureas and -carbodiimides, analogues of the insecticide/acaricide diafenthiuron, towards the carmine spider mite (Tetranychus cinnabarinus Boisd.) and the two-spotted spider mite (T. urticae Koch) was analysed using QSAR methodology. A canonical correlation analysis allowed for the establishment of a prediction model and the identification of outliers within that model. The chemodynamic behaviour of certain compounds in the two series, including these outliers, determined by using photochemical experiments in the laboratory as well as in the glasshouse, was shown to be responsible for anomalous results obtained in the biological tests. It was found from the above study that the biological activity towards both spider mite species is extremely sensitive to the kinetics of formation of the carbodiimides from the corresponding thioureas and to the photostability of the former. The results obtained with a thiourea which underwent no appreciable photochemical transformation into the corresponding carbodiimide supported the hypothesis that the thioureas are also in-vivo propesticides of the acaricidal carbodiimides.  相似文献   
26.
Canine leishmaniasis is an endemic disease in the Mediterranean area caused by the protozoan Leishmania infantum, which usually produces renal failure. Sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blot using antibodies to IgG and IgA from dogs were carried out in the urine of 22 dogs with leishmaniasis diagnosed by ELISA and confirmed by PCR, and 20 healthy dogs. The results were compared to renal function laboratory tests and to those from a histopathological study of the kidneys from sick animals that died naturally or were euthanized. Five different bands with molecular weights ranging from 10 to 110 kDa were obtained from the electrophoresis of the urine of healthy dogs. 33.5% of total proteins corresponded to low molecular weight proteins and the other proteins had middle and high molecular weights. However, in the group with leishmaniasis, a maximum of 11 different bands with molecular weights ranging from 10 kDa to 150 kDa were displayed in the electrophoresis of the urine. The urine electrophoretic pattern in the sick dogs was classified as mixed (proteins with high and low molecular weights) because low molecular weight proteins made up 57.9% and the rest of the proteins had middle and high molecular weights. In Western blot, none of the healthy dogs showed excretion of IgG and/or IgA, whereas IgG and IgA were detected in the Western blot of urine of 68% and 55% respectively of dogs with leishmaniasis. The results obtained in the leishmaniasis group agreed with glomerular and tubular damage, which were confirmed by the histopathological findings.  相似文献   
27.
OBJECTIVE: To determine whether atropine altered the degree of mucosal eversion during jejunal resection and anastomosis in the dog. STUDY DESIGN: Part I: Prospective, blinded, randomized, controlled study using a therapeutic dose (0.04 mg/kg systemic) of atropine. Part II: Prospective, unblinded, assigned, controlled study using a pharmacologic (0.04 mg/kg local arterial) dose of atropine. ANIMALS: Part I: Twenty-two young adult female Beagle dogs used during a nonsurvival third-year veterinary student surgical laboratory (small intestinal resection and anastomosis). Part II: Ten young adult female Beagle dogs used immediately after completion of a nonsurvival third-year veterinary student orthopedic surgical laboratory. METHODS: Part I: Dogs were randomly assigned to receive either atropine (0.04 mg/kg), or an equal volume of saline, given intramuscularly (premedication) and again intravenously prior to intestinal resection. Part II: In each dog, atropine (0.04 mg/kg)/saline was alternately given in the proximal/distal jejunum. RESULTS: Part I: There was no clinically or statistically significant difference between systemic atropine and saline solution on the degree of jejunal mucosal eversion after resection. Part II: There was a statistically significant decrease in jejunal mucosal eversion with atropine compared with saline solution when injected into a local jejunal artery. CONCLUSION: Systemic atropine (0.04 mg/kg) does not alter the degree of jejunal mucosal eversion during resection and anastomosis. Jejunal intraarterial atropine (0.04 mg/kg) reduced jejunal mucosal eversion during resection and anastomosis. CLINICAL RELEVANCE: The clinical usefulness and consequences of jejunal arterial atropine administration to reduce mucosal eversion remain to be determined.  相似文献   
28.
Primary porcine endothelial cells have a limited life span in culture. After four to five passages, they tend to de-differentiate and eventually reach senescence. The aim of this work was to establish immortalized porcine aortic endothelial cell lines (AOCs) to facilitate in vitro studies of different pathological process involving the endothelium. Primary porcine aortic endothelial cells (PAECs) were transfected with a plasmid containing the SV40 genome and selected on the basis of morphological and phenotypical features. Flow cytometry analysis demonstrated uptake of acetylated low density lipoproteins (Ac-LDL) and constitutive expression of SLA class I, CD29, CD31, CD41/61, CD80/86, CD46, SWC3, and LAMP-1 antigens by all analyzed lines and showed little differences to primary cells. The functional similarity between primary and immortalized endothelial cells was demonstrated in a cytotoxicity assay using a human natural killer cell line (NKL) as effector. The AOCs cell lines should be valuable tools for in vitro study of the human immune response against pig endothelial cells. In addition, they would be very useful to gain insight in the pathogenesis of some viral haemorrhagic diseases of pig such as African swine fever (ASF) or classical swine fever (CSF).  相似文献   
29.
Hemangiosarcoma of the third eyelid in a cat   总被引:2,自引:0,他引:2  
A case of hemangiosarcoma of the third eyelid in a 15-year-old Domestic Short-haired cat is reported. A small red mass protruding from the anterior surface of the third eyelid in the left eye was present. Only mild bilateral conjunctivitis and nuclear sclerosis were revealed on initial ophthalmic examination. After anti-inflammatory treatment, surgery and cryotherapy were performed. On histopathologic examination the mass was located just beneath the conjunctival epithelium, suggesting that the conjunctiva was the tissue of origin. The tumor showed high cellularity and was composed of pleomorphic spindle and polygonal cells arranged in interlacing bundles and solid sheets. The presence of slit-like spaces between tumor cells containing erythrocytes demonstrated the vascular differentiation. Mitotic activity was moderate, but atypical mitoses were detected. The surgical area healed uneventfully and after 7 months there was no recurrence. To the authors' knowledge, this is the first report of conjunctival hemangiosarcoma of the third eyelid in a cat.  相似文献   
30.
Objective Canine leishmaniosis is a disease characterized by the wide distribution of the parasite throughout the tissues of the host. The purpose of this study was to describe the presence of Leishmania spp. and associated inflammation in ocular‐associated muscles of dogs with patent leishmaniosis. Procedures Smooth muscles (iris dilator muscle, iris sphincter muscle, ciliary muscle, Müller muscle, smooth muscle of the periorbita and smooth muscle of the nictitating membrane) and striated muscles (orbicularis oculi muscle, obliquus dorsalis muscle and dorsal rectus muscle) were evaluated. Routine staining with hematoxylin and eosin and immunohistochemistry to detect Leishmania spp. were performed on tissue sections. Results Granulomatous inflammation was seen surrounding muscular fibers and was composed mainly of macrophages with scattered lymphocytes and plasma cells. This infiltrate could be seen in 52/473 (10.99%) samples of smooth muscle and 36/142 (25.35%) samples of striated muscle. Parasites were detected in 43/473 (9.09%) samples of smooth muscle and in 28/142 (19.71%) samples of striated muscle. Conclusions To the authors’ knowledge, this is the first report assessing the presence of Leishmania spp. and associated infiltrate in intraocular, extraocular and adnexal smooth and striated muscles. The inflammation present in those muscles could contribute to clinical signs already described, such as blepharitis, uveitis, and orbital cellulitis.  相似文献   
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