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31.
The objective of the current study was to examine cyclooxygenase (COX), cytochrome P450 1A (CYP1A) and 2C (CYP2C) activity in bovine endometrial cell cultures following exposure to oxytocin (OT), interferon‐τ (IFN), estradiol (E2) and/or progesterone (P4). Bovine endometrial epithelial cells were treated with OT, IFN, a combination of OT+IFN or control (CON) media for 24 h. For the second experiment, cells were treated with E2, P4, a combination of E2 + P4 or CON media for 24 h. Treatments were performed in triplicate, and the experiment was repeated four times (n = 12 per treatment). Treatment with OT alone increased (p < 0.01) activity of COX compared with CON; however, OT alone did not alter activity of CYP1A (p = 0.55) or CYP2C (p = 0.46) compared with CON. Activity of CYP1A and CYP2C was decreased in cells exposed to IFN (p < 0.01) or OT+IFN (p < 0.01) compared with CON. Treatment with E2 alone did not alter activity of CYP1A (p = 0.64) or CYP2C (p = 0.06) compared with CON. Activity of CYP1A and CYP2C was decreased (p < 0.01) in P4 vs CON. In summary, IFN exposure, irrespective of OT treatment, decreased the activity of CYP1A and CYP2C. Activity of CYP1A was decreased following P4 treatment alone, while that of CYP2C was decreased following both P4 and E2 + P4 treatment. The mixed function monooxygenase enzymes, CYP1A and CYP2C, have been implicated in synthesizing embryotoxic compounds; therefore, downregulation in the endometrium may be necessary during maternal recognition of pregnancy.  相似文献   
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SUMMARY The response of sheep to a recombinant multivalent footrot vaccine containing pilus antigens was examined after the administration of two doses of vaccine at Intervals ranging from 2 to 52 weeks. Agglutinating antibody titres were measured 3 weeks after the second vaccination and showed that lengthening of the interdose interval results in higher agglutinin titres. The capability of sheep to mount an increasingly strong immune response as the interval between doses is increased provides an opportunity to maximise the usefulness of vaccination by administering the first dose well before an expected footrot transmission period. This advantage of increasing the interdose interval has not been reported for traditional, whole-cell footrot vaccines, and use of the new pilus vaccine in this manner may improve prospects for disease control. Furthermore, sheep given a third dose either 6 or 12 months after their initial two-dose vaccination program achieved significantly higher titres than those elicited after the second dose, suggesting the likelihood of further improvement in disease control in successive seasons.  相似文献   
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Avicennia marina (Forrsk.) Vierh. was planted in 1969 at Nahoon Estuary, East London, followed a few years later by the planting of Bruguiera gymnorrhiza (L.) Lam. and Rhizophora mucronata (L.) among the larger A. marina trees. This study tested the hypothesis that mangroves have expanded and replaced salt marsh over a 33-year period (1978–2011). It provides important information on mangroves growing at higher latitudes, where they were thought to not occur naturally due to lower annual average temperatures. It further provides insights on future scenarios of possible shifts in vegetation types due to climate change at one of the most southerly distribution sites worldwide. The expansion of mangroves was measured using past aerial photographs and Esri ArcGIS Desktop 10 software. In addition, field surveys were completed in 2011 to determine the population structure of the present mangrove forest and relate this to environmental conditions. The study showed that mangrove area cover increased linearly at a rate of 0.06 ha y?1, while the salt marsh area cover also increased (0.09 ha y?1) but was found to be variable over time. The mangrove area is still relatively small (<2 ha) and expanded mostly over a bare sandflat area. Avicennia marina was the dominant species and had high recruitment (seedling density was 33 822 ± 16 364 ha?1). Only a few Bruguiera gymnorrhiza and Rhizophora mucronata individuals were found (<10 adult trees), although observations indicate that some young plants are becoming established away from the parent plants. The site provides opportunities for studies on mangrove/salt marsh interactions in response to a changing climate. Mangroves should not be planted in non-native areas as they may become invasive outside their natural range. However, future increases in temperature will certainly lead to a southerly expansion of mangoves in South African estuaries.  相似文献   
34.
UV irradiation enhanced the resistance of grapefruit against the development of green mold décay caused byPenicillium digitatum, the main postharvest pathogen of citrus fruit, and significantly inhibited the fungus’ growth at the fruit wound sites. Immunoblotting analysis using specific citrus chitinase and β-1,3-endoglucanase antibodies, showed that UV irradiation, wounding of the fruit, or a combination of these two treatments, induced the accumulation of a 25 kD chitinase protein in the fruit’s peel tissue. On the other hand, UV irradiation or wounding of the fruit alone was unable to induce the accumulation of 39 and 43 kD β-1,3-endoglucanase proteins, but the combination of the two treatments increased these protein levels. It is suggested that both chitinase and β-1,3-endoglucanase may play a role in the UV-induced resistance of grapefruit againstP. digitatum. Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No. 403/99. http://www.phytoparasitica.org posting June 3, 1999.  相似文献   
35.
OBJECTIVE: To study the occurrence of Chlamydia psittaci in domesticated and wild birds and compare the sensitivity of molecular detection with cell culture isolation. DESIGN: Study of cell culture isolation and PCR detection of C psittaci in avian samples. PROCEDURE: Samples were obtained from 485 birds. Domesticated birds were selected at random from pet shops, private aviaries and zoos, while wild birds were captured locally, sampled, and immediately released. Swabs were collected from choanal slit, conjunctiva and cloaca of each bird and pooled. Samples were divided into equal portions for use in PCR dot-blot and cell culture detection. PCR and dot-blot detection was based on the ompB gene. RESULTS: Prevalence of infection varied markedly between flocks of captive birds. It was highest where there were frequent changes in the flock members or where there were many birds confined in small areas. C psittaci was not detected in wild birds or water birds. The sensitivity of cell culture compared to PCR dot-blot detection was 68%. All samples positive by cell culture were also positive by PCR. CONCLUSIONS: PCR-dot blot detection of C psittaci in birds appears to be more sensitive than cell culture isolation in this study. C psittaci infection of birds may occur in clinically normal captive birds.  相似文献   
36.
A regional survey was conducted in Nepal for antibody to Japanese encephalitis virus (JEV) in domestic animals. Sera from pigs, and limited numbers of ducks and horses were collected from 16 districts in 2002-2003 and subjected to three serological tests. Of 270 porcine sera tested by C-ELISA, 55% were found positive for the presence of antibodies against Japanese encephalitis virus. Additional testing for IgM antibody to JEV revealed less than 2% of C-ELISA positive sera had evidence of recent JEV infection. Plaque reduction neutralisation tests (PRNT) using JEV, Murray Valley encephalitis (MVEV) and Kunjin (KUNV) viruses implicated JEV as the flavivirus associated with the observed antibody response in most sero-positive pigs. However, eight porcine sera with predominant neutralising antibody for KUNV (an Australasian subtype of West Nile Virus) provided evidence for the circulation of West Nile virus in Nepal.  相似文献   
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Abstract

CASE HISTORIES: Four adult kunekune pigs developed facial swelling at the base of the right ear that ruptured and discharged food material. A further six pigs that had similar clinical signs were reported by members of the New Zealand Kunekune Association who responded to an email survey, one of which was confirmed by post-mortem examination.

CLINICAL FINDINGS: Inside the mouth of each pig there was an opening at the junction of the body and ramus of the mandible just lateral to the most caudal visible molar that was impacted with masticated feed. The food packed into the mandible resulted in infection and progressive erosion of the medullary cavity of the bone until it reached the ramus where it eroded through the lateral cortex. The feed material then tracked through the soft tissues to form a subcutaneous abscess, which eventually ruptured resulting in a draining lesion. In Case 2, which had had the lesion for 2 years, the cavity in the mandible was lined with mucosa that had healed to the skin to produce a fistula. In all four pigs there was also a lesion in the left side of the mandible that was not as developed as that on the right side.

DIAGNOSIS: The facial swellings were produced by feed material that had impacted into the mandible through an opening immediately caudal to the cheek teeth and then emerged through one or more lesions in the lateral aspect of the ramus of the mandible.

CLINICAL RELEVANCE: Although it has not been previously reported, anecdotal reports and our survey suggest that this condition may occur relatively frequently in kunekune pigs. It should be considered as a differential diagnosis for facial swellings and discharging lesions in these animals.  相似文献   
40.
Extract

Lytic lesions with microscopic features similar to those of vaccine-site sarcomas were diagnosed in the distal femur of two young neutered male cats, one a 20-month-old Birman and the other an 18-month-old domestic short-hair (DSH). Radiographically, there was extensive destruction of trabecular and cortical bone in the metaphysis and/or epiphysis of the distal femur. The DSH cat also had angular deformity of the distal femur due to asymmetrical involvement of the physis. Histologically, the lesions in both cats consisted of dense, interwoven bundles of fibrous connective tissue, amongst which there were variable numbers of plump malignant mesenchymal cells, often with very large, hyperchromatic nuclei and irregularly shaped nucleoli. Several focal aggregates of small lymphocytes were present in both tumours. Although neither cat had apparently been vaccinated in the hindlimb it is possible that the tumours had been triggered by injection of some other irritant material.  相似文献   
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