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61.
The expression of 12 different aquaporin subtypes in equine endometrium was examined at the mRNA and protein level. Endometrial samples were obtained during anoestrus, oestrus, 8, and 14 days after ovulation in non‐pregnant mares, and 14 days after ovulation in pregnant mares. Quantitative PCR revealed a time‐dependent pattern for all aquaporin subtypes examined except for AQP10 and 12. AQP3, 5 and 7 showed highest mRNA abundance 8 days after ovulation, while AQP0 and 2 were most abundant at Day 14 of the cycle in non‐pregnant mares. At 14 days of pregnancy, AQP1, 4, 8, 9 and 11 displayed highest expression levels. Western blot analysis confirmed protein expression of AQP0, 2 and 5. Immunohistochemistry localized protein expression to luminal and glandular epithelial and stromal cells. AQP0 staining intensity was highest in samples obtained on Day 14 of the oestrous cycle. AQP2 immunoreactivity seemed to be stronger in samples collected 14 days after ovulation from non‐pregnant animals, in particular luminal epithelial staining. Samples collected 8 days after ovulation from cyclic animals were characterized by intense AQP5 staining of glandular epithelium, predominantly in the deeper glands. Progesterone treatment of anoestrous mares did not enhance expression of AQPs, indicating that factors other than progesterone are required for the up‐regulation of certain AQP subtypes during dioestrus. In conclusion, it seems that an equine‐specific collaboration of aquaporin subtypes contributes to changes in endometrial fluid content occurring throughout the oestrous cycle and contributes to endometrial receptivity during early pregnancy in the mare.  相似文献   
62.
The development of antral ovarian follicles entails fluid accumulation, but the mechanisms regulating water flux are unknown. Aquaporins are small, integral membrane proteins facilitating passive movement of water, some of which are known to be regulated by steroid hormones. The aim of this study was to determine whether testosterone (T) influences water transport in porcine granulosa cells. To assess water movement, the swelling of granulosa cells when moved from isotonic (319 mOsm) to hypotonic (95 mOsm) medium was measured after 12‐hour pre‐incubation in the presence of either testosterone (T), the antiandrogen 2‐hydroxyflutamide (HF) or HF and T together. Pre‐incubation with T increased the swelling of granulosa cells (p < 0.01) and this was abolished by HF (p < 0.001). Neither T nor HF affected cells in isotonic medium (319 mOsm). The results indicate that T acting via intracellular androgen receptors increases water permeability of porcine granulosa cells, probably through the regulation of aquaporin activity.  相似文献   
63.
CASE HISTORY An 18-month clinical course of chronic ill-thrift, weight loss and emaciation, and eventual death occurred in a group of 520 translocated elk of mixed age and sex. Trans-location was carried out without regard to animal welfare or health risks associated with the translocation. Mortality was approximately 84% (436/520) despite supportive nutritional and medical treatment.

PATHOLOGICAL FINDINGS: General clinical and post-mortem examinations indicated only Se and Cu imbalances and nutritional inadequacy. Additional purposeful post-mortem examination and histological evaluation of tissue sections from four of the affected adult elk demonstrated elevated abomasal pH and proliferative abomasal lesions as the most significant findings, consistent with Type-II ostertagiosis; intra-lesional nematodes were seen in the abomasum of two animals.

DIAGNOSIS: Fading elk syndrome, or abomasal parasite syndrome in elk.

CLINICAL RELEVANCE: Abomasal parasite syndrome initiated by Type-II ostertagiosis should be considered as a differential diagnosis in cases of ill-thrift and wasting in elk or elk-red deer hybrids. Changes to the architecture and secretory function of the abomasal wall lead to apparently irreversible digestive pathophysiology and nutritional disease.  相似文献   
64.
In the horse, breeding induces a transient endometrial inflammation. A subset of mares are unable to resolve this inflammation, and they are considered susceptible to persistent mating‐induced endometritis PMIE Select seminal plasma proteins cysteine‐rich secretory protein‐3 (CRISP‐3) and lactoferrin have been shown to affect the innate immune response to sperm in vitro. The objective of this study was to determine whether the addition of CRISP‐3 and lactoferrin at the time of insemination had an effect on the mRNA expression of endometrial cytokines in susceptible mares after breeding. Six mares classified as susceptible to PMIE were inseminated during four consecutive oestrous cycles with treatments in randomized order of: 1 mg/ml CRISP‐3, 150 μg/ml lactoferrin, seminal plasma (positive control) or lactated Ringer's solution (LRS; negative control) to a total volume of 10 ml combined with 1 × 109 spermatozoa pooled from two stallions. Six hours after treatment, an endometrial biopsy was obtained for qPCR analysis of selected genes associated with inflammation (pro‐inflammatory cytokines interleukin (IL)‐1β, IL‐8, tumour necrosis factor (TNF)‐α, interferon (INF)‐γ, anti‐inflammatory cytokines IL‐1RN and IL‐10, and inflammatory‐modulating cytokine IL‐6). Seminal plasma treatment increased the mRNA expression of IL‐1β (p = .019) and IL‐8 (p = .0068), while suppressing the mRNA expression of TNF (p = .0013). Lactoferrin also suppressed the mRNA expression of TNF (p = .0013). In conclusion, exogenous lactoferrin may be considered as one modulator of the complex series of events resulting in the poorly regulated pro‐inflammatory response seen in susceptible mares.  相似文献   
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66.
The objective of this study was to compare results from endometrial cytological and bacteriological examinations obtained by two different laboratories. One laboratory used endometrial swabs and the other endometrial biopsies for the examinations. A higher proportion of sterile, cytology positive cases were found in the laboratory using swabs (148/401 [37%] vs 12/237 [5%], P < .0001). In both laboratories it was found that positive cytology was less likely to occur when Escherichia coli was isolated than if other species were isolated. This tendency was significant in both laboratories (P < .05 vs P < .0001).  相似文献   
67.
BACKGROUND: In spite of concern regarding potential non‐target effects of GM crops, few studies have compared GM pest control with conventional methods. The impacts of cypermethrin and oilseed rape expressing oryzacystatin‐1 (OC‐1) were compared in this study on the predator Chrysoperla carnea (Stephens). RESULTS: Adults fed purified rOC‐1 showed a subtle shift in digestive protease profile, with an increasing reliance on serine proteases (chymotrypsin), increase in aspartic proteases and a slight reduction in elastase activity. Although there were no effects on mortality, onset of oviposition was delayed; however, once egg production commenced, egg laying and hatching success rates were comparable with those of controls. Oryzacystatin‐1 expressed in pollen showed no detrimental effects. Cypermethrin had no effect on mortality owing to high levels of non‐specific esterase activity resulting in partial breakdown of the insecticide. In spite of this, there was a significant delay in onset of oviposition and a significant reduction in egg production and viability. CONCLUSION: This study demonstrates the potential for pest management to impact on predators, but importantly it highlights the ability of the predator to detoxify/respond to treatments with different modes of action. In this case, exposure to an insecticide carried a greater fitness cost than exposure to a protease inhibitor expressed in transgenic crops. Copyright © 2009 Society of Chemical Industry  相似文献   
68.
Remediation of 150 000 m3 of sediment containing400 kg PCB was performed by suction dredging in asmall lake in Sweden in the summers of 1993 and 1994.Upon project completion calculations indicated that97% of the PCB was deposited in a landfill withsubsequent low transport to the surroundings, andthat 2.9 kg was left in the lake sediment.Concentrations of PCB that were measured weekly in thewater leaving the lake were 12 ng/L (geometric mean)during dredging, not exceeding 30 ng/L and notsignificantly higher than in investigations preceedingthe remedial action. The concentration of PCB wasnegatively correlated to water discharge andpositively correlated to water temperature. PCBtransport in the river was correlated to waterdischarge but not to the dredging activity. Duringdredging of the most contaminated part of the lake,the dredging area was screened off by a geotextilesilt curtain that reduced leakage of PCB to the riverdownstream.  相似文献   
69.
The formation of a Bose-Einstein condensate of a dilute atomic gas has been studied in situ with a nondestructive, time-resolved imaging technique. Sodium atoms were evaporatively cooled close to the onset of Bose-Einstein condensation and then suddenly quenched to below the transition temperature. The subsequent equilibration and condensate formation showed a slow onset distinctly different from simple relaxation. This behavior provided evidence for the process of bosonic stimulation, or coherent matter-wave amplification, crucial to the concept of an atom laser.  相似文献   
70.
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