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The original article to which this Correction refers was published in Pest Management Science 58 (7): 649–662 (2002).Copyright © 2004 Society of Chemical Industry  相似文献   
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The lymphocyte populations of the bovine gut lamina proprial (LP) and epithelial tissues were isolated and characterized with respect to cells bearing surface and cytoplasmic immunoglobulin (Ig). Functional characteristics of cells from the two tissues, including responsiveness to Concanavalin A (Con A), anti-bovine immunoglobulin (anti-Ig), Con A supernatants of bovine peripheral blood lymphocytes (bConA sup) and recombinant human IL-2 (rhIL-2), were also assessed. Less than 1% of the mononuclear cells in the epithelial tissue (IEL) stained for cytoplasmic Ig, and 9% stained positively for surface Ig. IEL did not proliferate in response to anti-Ig, although cells of this population did respond to Con A, bConA sup, and rhIL-2. Twenty-seven percent of bovine gut LP lymphocytes stained for surface Ig, while 39% of these cells were positive for cytoplasmic Ig. LP lymphocytes proliferated in response to all four stimulants used, Con A, anti-Ig, bConA sup and rhIL-2.  相似文献   
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Dermal microdialysis, a relatively noninvasive technique, allows investigation of the changes in cellular mediators released during cutaneous allergic responses. This technique was used to evaluate the effect of cyclosporin A, an immunosuppressive drug used for treatment of canine atopic dermatitis, on the cutaneous release of two pro-inflammatory mediators following intradermal allergen challenge. Four beagle dogs spontaneously sensitized to Ascaris suum were treated for 1 month with oral cyclosporin A. At days 0, 15 and 30 of the treatment, dialysis probes were inserted into the skin of the back, and 20 microL of A. suum antigen was injected intradermally at each site. At timed intervals, dialysate was collected and assayed for histamine and prostaglandin D(2) and the wheal area was measured. Mean histamine concentration and wheal area were significantly lower at days 15 and 30 of treatment, compared with day 0. However, prostaglandin D(2) concentration was not significantly reduced. The inhibition in histamine release after intradermal challenge, by cyclosporin, confirms its anti-inflammatory action in the dog. Dermal microdialysis provides a useful tool for investigating canine allergic reactions and their modulation by drugs.  相似文献   
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Are extinctions of marine vertebrates as rare and unlikely as current data indicate? Long-term research surveys on the continental shelf between the Grand Banks of Newfoundland and southern New England reveal that one of the largest skates in the northwest Atlantic, the barndoor skate (Raja laevis), is close to extinction. Forty-five years ago, research surveys on St. Pierre Bank (off southern Newfoundland) recorded barndoor skates in 10% of their tows; in the last 20 years, none has been caught, and this pattern of decline is similar throughout the range of the species.  相似文献   
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The aim of the current study was to determine the possible effects of progestagen oestrous synchronization on vascular endothelial growth factor (VEGF) expression during sheep luteogenesis and the peri‐implantation period and the relationship with luteal function. At days 9, 11, 13, 15, 17 and 21 of pregnancy, the ovaries from 30 progestagen treated and 30 ewes cycling after cloprostenol injection were evaluated by ultrasonography and, thereafter, collected and processed for immunohistochemical evaluation of VEGF; blood samples were drawn for evaluating plasma progesterone. The progestagen‐treated group showed smaller corpora lutea than cloprostenol‐treated and lower progesterone secretion. The expression of VEGF in the luteal cells increased with time in the cloprostenol group, but not in the progestagen‐treated group, which even showed a decrease between days 11 and 13. In progestagen‐treated sheep, VEGF expression in granulosa‐derived parenchymal lobule capillaries was correlated with the size of the luteal tissue, larger corpora lutea had higher expression, and tended to have a higher progesterone secretion. In conclusion, the current study indicates the existence of deleterious effects from exogenous progestagen treatments on progesterone secretion from induced corpora lutea, which correlate with alterations in the expression of VEGF in the luteal tissue and, this, presumably in the processes of neoangiogenesis and luteogenesis.  相似文献   
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Chlamydia psittaci was detected by PCR in the lung and equine foetal membranes of two aborted equine foetuses and one weak foal from two different studs in Victoria, Australia. The abortions occurred in September 2019 in two mares sharing a paddock northeast of Melbourne. The weak foal was born in October 2019 in a similar geographical region and died soon after birth despite receiving veterinary care. The detection of C. psittaci DNA in the lung and equine foetal membranes of the aborted or weak foals and the absence of any other factors that are commonly associated with abortion or neonatal death suggest that this pathogen may be the cause of the reproductive loss. The detection of C. psittaci in these cases is consistent with the recent detection of C. psittaci in association with equine abortion in New South Wales. These cases in Victoria show that C. psittaci, and the zoonotic risk it poses, should be considered in association with equine reproductive loss in other areas of Australia.  相似文献   
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