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11.
A 15-year-old, pregnant Dutch Warmblood mare was exhibiting intermittent hemorrhage secondary to a large vestibulovaginal varicosity. The vessel was reduced with transendoscopic Nd:YAG laser photocoagulation. This technique is minimally invasive compared with traditional surgical ligation, and significantly decreases the risk of severe hemorrhage, especially with advancing pregnancy. One laser treatment resulted in complete reduction in vessel size and allowed the pregnancy to continue to term without incident or further vaginal hemorrhage.  相似文献   
12.
1,25-Dihydroxycholecalciferol (DHCC), isolated from kidney homogenates incubated with 25-hydroxycholecalciferol (HCC), stimulated the release of previously incorporated (45)45Ca from fetal rat bones in organ culture, at concentrations of 10(-10) to 10(-8)M. The dose response curves for 1,25-DHCC and 25-HCC, the parent compound, are parallel, but 1,25-DHCC is about 100 times as potent on a weight basis. Brief exposure to maximum doses of either agent leads to prolonged bone resorption.  相似文献   
13.
The capacity of a TK‐negative (TK ) and gI/gE‐negative (gI/gE ) pseudorabies virus (PRV) mutant to protect pigs against Aujeszky's disease carried out by experimental infection with a virulent PRV strain, was tested. There were three groups, each of four susceptible pigs which were inoculated twice by two different schedules. Group 1 received the modified virus by the intradermal (first inoculation)‐intramuscular (second inoculation) routes; group 2 was treated by the intranasal (first inoculation)‐intramuscular (second inoculation) routes. The third group was left untreated as the control. All of the pigs were challenged intranasally with a virulent PRV strain and they were subsequently injected with dexamethasone. Two pigs in each group were necropsied on days 5 and 15 after dexamethasone inoculation. The challenge exposure resulted in mild clinical signs, increase in growth and a shorter period of virus shedding in vaccinated pigs, whereas the control group showed severe signs of Aujeszky's disease. No difference in the titre of the virulent virus which was excreted by pigs of all three groups, was observed and all animals seroconverted. Both the mutant strain and the wild‐type virus established a latent infection although only the latter was reactivated and shed. Slight lesions were observed in target tissues of the vaccinated animals and no significant differences were detected between the two inoculation schedules.  相似文献   
14.
Aiming to control the citrus leafminer Phyllocnistis citrella St. while at the same time protecting the biological equilibrium and mainly the beneficial insect Cales noacki, experiments have taken place in the regions of Argolis and Fthiotis, Greece in 1996 and 1997. Insegar (fenoxycarb) 2 5 WP was applied on young citrus trees. During 1996, the compound, applied every 10 days at a rate of 30 g/hI (with or without adjuvant), gave satisfactory protection from P. citrella without substantially harming C. noacki populations. No phytotoxicity symptoms were observed during the experiments.  相似文献   
15.
Magneto-optical imaging was used to visualize the inhomogeneous penetration of magnetic flux into polycrystalline TlBa2Ca2Cu3Ox films with high critical current densities, to reconstruct the local two-dimensional supercurrent flow patterns and to correlate inhomogeneities in this flow with the local crystallographic misorientation. The films have almost perfect c-axis alignment and considerable local a- and b-axis texture because the grains tend to form colonies with only slightly misaligned a and b axes. Current flows freely over these low-angle grain boundaries but is strongly reduced at intermittent colony boundaries of high misorientation. The local (<10-micrometer scale) critical current density Jc varies widely, being up to 10 times as great as the transport Jc (scale of approximately 1 millimeter), which itself varies by a factor of about 5 in different sections of the film. The combined experiments show that the magnitude of the transport Jc is largely determined by a few high-angle boundaries.  相似文献   
16.
Increasing mercury contents are reported from freshwater systems and fish in northern Europe and North America. Mercury input from soils is a major source with the leaching being affected by increased atmospheric mercury deposition compared to pre-industrial times and by other environmental conditions such as acid rain. The results of a mathematical model-calculation of vertical inorganic Hg(II) leaching in a Scandinavian iron-humus podzol under different atmospheric input rates of mercury are presented. Leaching under background rain conditions was calculated to be considerably stronger than under acid rain conditions. Increasing fractions of deposited soluble or solute atmospheric mercury were leached from the O f(h)-horizon with decreasing soil content of soluble mercury under acid rain conditions; this effect was less pronounced under background rain conditions. The steady state concentrations of soluble mercury of the upper soil horizons were calculated and compared with the actual concentrations of total (= soluble + insoluble mercury) and extractable (= estimate of soluble) mercury measured in these horizons. The results indicate that even if the deposition of airborne mercury to soil is strongly reduced, the total mercury content of the soil decreases only slowly. It may take decades or even centuries before a new steady state concentration of total mercury is established in the soil. The decrease of the mercury concentration in the O f(h)-horizon is probably largely dependent on the turnover of organic matter, binding most of the deposited airborne mercury in an insoluble form. Hence, present day mercury leaching is likely to be dominated by mercury deposited during former times and temporarily retained in an insoluble form in the organic matter.  相似文献   
17.
Animals used in sport should be treated as required to ensure animal welfare but any such use of medication should also be controlled to ensure integrity. Pharmacokinetic studies on groups of six greyhounds were performed to measure plasma and urine levels of carprofen and firocoxib to inform medication control advice. Using the standard methodology for medication control the Irrelevant Plasma Concentration was determined as 20 and 2 ng/mL for carprofen and firocoxib, respectively. The Irrelevant Urine Concentration was also determined as 0.3 and 2 ng/mL for carprofen and firocoxib, respectively. These Irrelevant Plasma and Urine Concentrations will allow laboratory Screening Limits, Detection Times and Withdrawal Time advice to be determined and publicised by regulators of greyhound racing. The Screening Limits will also inform Recommended Limits of Detection if meat-containing residues of these medications are fed to greyhounds.  相似文献   
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19.
Abstract. The synthetic LH-RH (luliberine) has proved to be successful in inducing the ovulation of sterlet, Acipenser ruthenus L. Three dosages of LH-RH 50, along with carp pituitary, and 100 and 300 μg/kg of body weight were administered, and 100 and 300 μg of LH-RH/kg body weight were found to be successful in ovulation. Spawners were kept at low temperature (9–12°C). Forty-two hours after treatment the eggs entered ovulation in the ovary and became suitable for stripping. The ripening ratio for spawners varied between 75 and 83%. The eggs that could be obtained by opening the abdominal wall were fertilized with milt diluted with pond water to avoid polyspermism. The fertility of the stripped eggs was 89–90%. Despite a reduced number of subjects (12 treated, 2 control females), as a result of the favourable fertilization percentage, approximately 55 000 fingerlings were reared in tanks to approximately 5–7cm in size.  相似文献   
20.
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