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71.
Landscape Ecology - Rivers, landscape, and climate can alter patterns of gene flow and consequently, shape intraspecific genetic variation. While rivers are predicted to halt gene flow in...  相似文献   
72.
Summary Generation of Simple Sequence Repeat (SSR) DNA markers was based on the construction of genomic DNA library of avocado (Persea americana M.). The library was screened with the four dinucleotide probes (AG), (AT), (GC) and (CA). Positive clones were sequenced to validate the presence of simple sequence repeats (SSR) and to generate polymerase chain reaction (PCR) primers based on the sequences flanking the simple sequence repeat. Twenty six different pairs of primers which yield a PCR product in the initial screening were synthesized. The SSR A1E11 was found to have eleven alleles while A3F8 has eight alleles. The SSRs in avocado were found to be inherited in a Mendelian fashion.Contribution from the Agricultural Research Organization, The Volcani Center, Bet-Dagan, Israel. No. 1335-E, 1994 series.  相似文献   
73.
Objectives To characterise the changes caused to sheep skin by deep dermal and subcutaneous injections of sodium lauryl sulfate (SLS) and describe the subsequent healing process. Procedure On 6 sheep 20 small areas of skin were each given deep dermal and subcutaneous injections of 0.2 mL of 7% SLS. Biopsies were collected at intervals up to 28 days after treatment and the histological changes in each of the treated skin samples were assessed and graded. Results There was no evidence of alterations in behaviour, weight gain or appetite of the sheep following the injections. Initial swelling of the treated site subsided by day 14, leaving a firm, slightly raised crust. At day 21, the treated area was depressed and covered by a scab, which sloughed completely by day 28. There was necrosis of the subcutis and deep dermis 2 min after treatment, followed by inflammation, fibroplasia, angiogenesis and tissue remodelling. Conclusion Injection of SLS caused almost immediate local necrosis followed by eschar formation, sloughing and scarring of treated skin. Deep dermal and subcutaneous SLS is potentially useful as a chemical alternative to mulesing.  相似文献   
74.
Background Benign mixed tumours (BMTs) are frequently found in the mammary glands of female dogs, but the factors determining malignant transformation in these tumours are unknown. Objective To evaluate the expression of the oncoproteins, human epidermal growth factor receptor 2 (HER‐2) and epidermal growth factor receptor (EGFR), in 46 carcinomas in BMTs (CBMTs) and to verify their possible association with the malignancy of the tumours. Methods Immunohistochemical expression was analysed in benign and malignant components separately, and then compared with 74 cases of BMTs. Results Among the CBMTs, positivity for HER‐2 was found in the benign histological component of 4.3% (2/46), in the malignant epithelial non‐invasive component of 14.8% (4/27) and in the malignant invasive epithelial component of 13.6% (6/44) of cases. Two of the 24 (8.3%) BMTs were positive for HER‐2. There was no relationship between HER‐2 and the tumour components. There was no significant difference between BMTs and CBMTs. Positivity for EGFR was found in the benign component of 17.4% (8/46) of the CBMTs, in the malignant epithelial non‐invasive component of 40.7% (11/27%) and in the invasive epithelial malignant component of 45.4% (20/44). EGFR positivity was significantly associated with the invasive component of CBMTs. Conclusion EGFR may contribute to malignant epithelial transformation of BMTs. In contrast, HER‐2 overexpression may not be associated with the acquisition of a malignant epithelial phenotype.  相似文献   
75.
The lectin‐binding pattern was compared in the normal and pathological uterus of sows during the ovarian cycle. The following biotinylated lectins were used: Con A, DBA, SBA, PNA, RCA‐I, UEA‐I and WGA. Glycoconjugate labelling showed differences between phases of ovarian cycle and presence of morphologic lesions. Cystic endometrial hyperplasia increased the RCA‐I reaction in the apical region of the glandular epithelium. There was higher intensity of labelling of WGA in the glandular epithelium in uteri with endometritis. In addition, increased Con A binding in the glandular epithelium and mild reduction of UEA‐I reactivity in the glycocalyx of the glandular epithelium were detected in the cases of endometritis. The results of this study show that morphologic alterations modify the sugar pattern in the porcine uterus. These modifications in glycoconjugates may be one of the reasons for decreased fertility in sows.  相似文献   
76.
77.
  1. Human translocations of non-native aquatic species are a global conservation challenge. Aquarists and anglers are two hobbyist groups whose practices are particularly likely to translocate non-native aquatic species, especially fish.
  2. This article aims to stipulate a change of perspective among these hobbyists, who – by acting simultaneously as anglers and aquarists – establish novel pathways for non-native fish.
  3. This study showed that: (i) 51 of 226 respondents to a questionnaire act simultaneously as anglers and aquarists; (ii) 53 of 237 non-native fish species in the European Union are used for both angling and aquarium hobbies; and (iii) hobbyists write online reports on the catch and exchange of a particularly invasive fish, the round goby (Neogobius melanostomus).
  4. This combination of knowledge on how hobbyists use non-native fish and the ecological impacts of round goby demonstrates how the impact of an invasive species can be influenced by the combined behaviours of anglers and aquarists.
  5. We suggest that future research in aquatic conservation should move beyond considering the commercial aquarium trade and angling as separate pathways for translocating non-native fish, and instead consider these hobbyist groups as interconnected.
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78.
  1. Conservation of riverine fish often aims to improve access to spawning grounds and restore longitudinal connectivity by removing migration barriers, and involves substantial investments. However, these investments also enable non‐native predators to invade upstream into spawning areas and potentially adversely affect the recruitment of threatened freshwater fish through egg or fry predation.
  2. Detecting egg predation is often challenging. Visual inspections of fish gut contents may underestimate predation of soft materials such as eggs and fry, which limits the discovery of predators preying upon these life‐stages. DNA‐based detection assays may offer a more sensitive tool to assess predation of soft materials.
  3. A conservation issue was confirmed by developing and applying a species‐specific DNA‐based detection assay: invasive round goby (Neogobius melanostomus) prey on the eggs or fry of the threatened common nase (Chondrostoma nasus) in Switzerland.
  4. DNA‐based detection assays were also developed for five other valuable native fish species, including endangered salmonid and cyprinid river spawners. The applicability of the assays was confirmed in a series of laboratory and field feeding experiments involving eggs and fish tissue. In addition, this work provides a guiding framework for conservation managers regarding the use and applicability of different DNA‐based detection approaches for gut content analysis.
  5. The results of this study could inform local conservation measures – such as temporary reductions in the density of round goby at spawning sites prior to spawning – and demonstrate how targeted application of species‐specific molecular markers may advance freshwater fish management.
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79.
The aim of this study was to characterize cytoskeletal intermediate filament proteins and glycoconjugates of syncytiotrophoblast, cytotrophoblast and decidual cells of feline endotheliochorial placenta. Samples from 12 normal pregnant female cats, after 45 ± 5 days of gestation, were obtained removing the uterine horns by hysterectomy. Sections were processed for routine observation and for immunohistochemistry using anticytokeratin, antivimentin and antidesmin antibodies. In addition, lectin histochemistry was performed using a panel of several biotinylated lectins to characterize glycosides expression profile. Cytotrophoblast and syncytiotrophoblast showed immunoreactivity only with acidic and basic cytokeratins. Decidual cells were only positive to vimentin, consistent with their origin from endometrial fibroblasts. Trophoblast expressed a broad population of glycans, highly exposing terminal N‐acetyl glucosamine residues and non‐sialylated galactose and N‐acetyl galactosamine oligomers. Oligosaccharides bound by Phaseolus vulgaris erythroagglutinin were the only highly branched Nlinked residues evidenced in cats, and they were restricted to the syncytium. Unlike results reported on humans, mice and rats on lectin affinity of decidual cells, sialid acids and complex Nlinked oligosaccharides were not demonstrated in cats. Glycosylation of proteins determines many of their final properties, thus becoming essential for the embryo‐maternal dialogue during implantation and placentation. Changes in glycosylation pattern have been related to pathological pregnancies in other species. Hence, the knowledge about glycosylation profile of the normal cat placenta may lead to a better understanding of both normal and pathological reproductive events.  相似文献   
80.
SUMMARY Clinical, diagnostic and biochemical features of generalised glycogenosis are described In 96 Brahman-type calves. Typically the calves were presented when about 6 months of age, with III-thrift and muscular weakness as the most common signs. Acidic α-glucosidase activity was reduced in peripheral blood lymphocytes and skeletal muscle. Muscle glycogen concentration was consistently higher in affected animals than In clinically normal cattle. Other observations in affected calves Included elevation of serum aspartate amlnotransferase and creatine kinase activities and excessive amounts of high molecular weight oligosaccharides in urine. Fine cytoplasmic vacuolation of neurones In the brain and spinal cord, skeletal muscle, myocardlum and of Purkinje fibres were consistent histological observations. Periodic acid-Schlff staining revealed the presence of glycogen-like material In peripheral blood lymphocytes of all affected calves, Indicating that this is a useful aid for the diagnosis of glycogenosis. While 3 of the 96 calves showed somewhat different clinical signs, the similarity of pathology and the biochemical and clinical evidence in the remainder suggested that, In these animals, the disease was expressed as a single syndrome.  相似文献   
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