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1.
The vascular endothelial growth factor (VEGF) is essential for follicular development by promoting follicular angiogenesis, as well as for the proliferation and survival of granulosa cells. The biological effects of VEGF are regulated by two membrane receptors, VEGFR1 and VEGFR2, and two soluble receptors, sVEGFR1 and sVEGFR2, which play an antagonistic role. Thus, the objective of this study was to identify the mRNA expression pattern of total VEGF, VEGFR1, VEGFR2, sVEGFR1 and sVEGFR2 in bovine preselected follicles (PRF) and post‐selected follicles (POF). The mRNA expression of these five genes in both granulosa cells (GC) and theca cells (TC) was compared between follicles classified as PRF and POF based on their diameter and on their ratio of estradiol/progesterone (E2/P4). Results showed a lower expression of mRNA of sVEGFR1 and sVEGFR2 in POF than in PRF (p < .05). Regarding the mRNA expression of total VEGF, VEGFR1 and VEGFR2, there was no difference between POF and PRF follicles (p > .05). Our results showed that the mRNA expression of VEGFR2 and sVEGFR1 was more abundant than the expression of VEGFR1 and sVEGFR2, while GC was the main source of mRNA for total VEGF. On the other hand, TC was the follicular compartment where the receptors were most expressed. Our results suggest that non‐dominant follicles maintain a greater concentration of the mRNA expression of both membrane and soluble VEGF receptors. On the other hand, follicular dominance is related to a reduction in the mRNA expression of sVEGFR1 and sVEGFR2, which may favour VEGF binding with VEGFR2 and, hence, improve the follicular health and development.  相似文献   
2.
CASE HISTORY A 3-year-old male Labrador retriever was presented with a history of dietary indiscretion followed by vomiting and abdominal pain.

CLINICAL FINDINGS AND TREATMENT: Abdominal ultrasonography revealed the presence of a fluid-filled cystic structure in the region of the pancreas. Flocculent, dark fluid was drained from the cystic structure during exploratory celiotomy prior to resection of the lateral cystic wall. Omentum was sutured into the cystic cavity to provide drainage and enhance immune response. A jejunostomy feeding tube was placed. Post-surgical care consisted of antibiotic therapy. The dog was clinically normal at 1 and 7 months post-operatively and the pancreas appeared normal on final ultrasonographic examination.

CLINICAL RELEVANCE: This case describes the use of omentum to provide physiological drainage of a pancreatic pseudocyst. This surgical technique may help clinicians manage patients with this condition in the future.  相似文献   
3.
Each of two dogs presented for multiple skin biopsies were sedated with intravenous medetomidine and lignocaine was injected subcutaneously to provide local anaesthesia for skin biopsy. One dog had a seizure during skin biopsy and again immediately following reversal of medetomidine with atipamezole. The other dog developed seizures 2 h following skin biopsy at which time the medetomidine was reversed with atipamezole. Both dogs were neurologically normal with no history of seizures prior to the procedure and remained neurologically normal for 14 weeks and 9 months, respectively, following the procedure. A drug interaction between the α2-adrenergic agonist medetomidine and lignocaine is suspected and highlights the potential for seizures following the subcutaneous administration of relatively large doses of lignocaine under medetomidine sedation.  相似文献   
4.
Effects of cecropin peptides on bacteria pathogenic to fish   总被引:1,自引:0,他引:1  
The antibacterial effects of synthetic cecropin B and cecropin P1 were tested against the fish-pathogenic bacteria Vibrio anguillarum, Vibrio salmonicida, Aeromonas salmonicida , Edwardsiella ictaluri and Yersinia ruckeri. Both cecropins were active against all bacteria tested, but the effect was strongly influenced by the growth media used. In brain heart infusion medium, the minimum inhibitory concentrations of cecropin B ranged from 0.3 to 1.3 μ m and from 0.3 to 1.0 μ m for cecropin P1, except for E. ictaluri , which was noticeably less sensitive to cecropin P1 (61 μ m ). The present authors have compared the bactericidal activity of these two peptides, showing that the killing rate for the selected bacteria was higher for cecropin B than for cecropin P1 . V. anguillarum was the most sensitive to the cecropins, and in the present study, no colony forming units were detected after 4 and 8 min of treatment with cecropin B and P1, respectively. Electron microscopy was performed to document the effect of cecropin on the bacterial surface.  相似文献   
5.
In many countries there has been much concern over maintaining biodiversity in natural ecosystems in the face of pressures such as changing land use and pollution. The 1992 UN Convention on Biodiversity calls upon signatories to develop national strategies for the conservation and sustainable use of biodiversity. In the UK, the potential impacts of sulphur and nitrogen deposition at the national level are being assessed using national critical loads and modelled deposition maps, together with available information on the occurrence of habitats and plant species. This simple approach gives an indication of the areas where atmospheric deposition may have impacts on biodiversity. The results of the analyses are presented and the strengths and weaknesses of the methods used are discussed. This first approach to considering the effects on biodiversity shows the importance of including the effects of atmospheric deposition in any biodiversity action plan. It also highlights those areas where more or improved information is required for the national strategy. With the modelled deposition data available, it would seem that reduced impacts are to be expected by 2010. However, higher resolution deposition data, better estimates of ammonium deposition, consideration of temporal aspects and the dynamics of change, and the use of higher resolution biological data sets are likely to suggest greater impacts than current predictions.  相似文献   
6.
ABSTRACT:   The immune system of the Atlantic cod ( Gadus morhua L) is unusual in that it cannot produce a specific antibody response upon immunization. Despite this, the cod is not particularly susceptible to infectious disease in its normal environment. This review examines the potential genetic basis for the lack of a specific antibody response in the cod. The genetics of cod immunoglobulins are compared with those of other well-characterized teleost fish. A review of the evidence suggests that deficiencies in the number, structure, organization, diversity and expression of both Immunoglobulin (Ig) heavy and Ig light chain genes in cod cannot explain its unusual antibody response. It is concluded that a deficiency in cod major histocompatibility (MH) class II molecules is a prime suspect for the lack of a specific antibody response in cod, and that testing of this hypothesis must await future experimentation.  相似文献   
7.
The binding of normal canine serum IgG and IgM to staphylococcal protein A is described. Virtually all (greater than 99%) of IgG and up to 90% of IgM could be removed from canine serum, utilizing this phenomenon. The nature of the bound material was confirmed by immunodiffusion in agar, radioimmunoassay, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Attempts to elute differentially IgG and IgM from protein A-Sepharose columns, using gradients of pH or the chaotropic agent sodium thiocyanate, were unsuccessful. This phenomenon provides a basis for the isolation of canine IgM from serum. Lymphocyte surface IgM, studied by lactoperoxidase-catalyzed membrane radioiodination and solubilization in nonionic detergent, also showed the property of binding to staphylococcal protein A.  相似文献   
8.
9.
By using a defined cDNA probe for the VH region of a murine phosphocholine-binding myeloma protein (S107) we have defined a family of distinct cross-hybridizing DNA sequences in genomic DNA of the goldfish. The estimated number of the goldfish putative VH family detectable by the S107 probe is about 36. By using two putative goldfish VH probes to analyze, by hybridization, the relationships among seven of the goldfish genomic clones, we have determined that the putative goldfish VH genes recognized by the S107 probe comprise at least several distinct families that are not closely related.  相似文献   
10.
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