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Cephalothoracopagus is a very rare form of conjoined twins and is characterized by fusion of heads and thoraxes with two separate spines, limbs and pelves. The aim of this study was to describe a case of female cephalothoracopagus kitten puppy. The most important gross findings involved the external body and some of the internal organs. Radiological features revealed main developmental abnormality of the head, spines and thorax. Authors discuss the pathogenic mechanisms of this condition, infrequently reported in veterinary practice, pointing out the importance of embryonic duplications commonly associated with dystocia.  相似文献   
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Summary

Giant reed (Arundo donax L.), a promising energy crop, is vegetatively-propagated from fragments of stems and rhizomes. This may limit large-scale cultivation, since it is time-consuming and involves considerable cost and effort. Tissue culture is an alternative to conventional methods of vegetative propagation and may represent a useful tool for large-scale propagation of plants for biomass production programmes. This report describes a protocol for the large-scale in vitro propagation of giant reed by adventitious bud formation. Stem nodes with dormant buds proved to be the most effective to initiate in vitro cultures giving the highest percentage of differentiated shoots (77%) compared to the other plant fractions tested. A sterilisation procedure using 5 g l–1 HgCl2 enabled the production of sterile explants. Moreover, early results indicated that late Autumn excision dates not only gave a higher percentage of well-developed shoots ( > 80%), but also a lower level of bacterial contamination (15 – 20%). 6-Benzylaminopurine (BAP) at 3.0 mg l–1 was most effective in promoting shoot multiplication when added to a basal medium containing Murashige and Skoog (MS) macro- and micro-nutrients, Morel’s vitamins, 30 g l–1 sucrose, and 7.0 g l–1 bacteriological agar supplemented with 1.0 mg l–1 indole-3-acetic acid (IAA) and 0.05 mg l–1 gibberellic acid (GA3). Rooting was successfully induced on the same basal medium used for proliferation, modified by halving the MS macro-nutrients and replacing BAP and the other growth regulators with 2.0 mg l–1 1-naphthaleneacetic acid (NAA). Successful acclimatisation (> 95% survival) of plantlets was carried out, even in late Winter, in a cold greenhouse or under simpler facilities such as shade nets.  相似文献   
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Summary

The present paper reports on somaclonal variation of leaf-derived ‘Tomuri’ and ‘Hayward’ somaclones regenerated at variable pH, and the effect of the in vitro selection pressure on their tolerance to lime-induced iron chlorosis as adult plants in pots and in the field. In most plants grown in pots, the above ground component length (AGL) and the node number (NN), and also root weight of ‘Hayward’, tended to increase with the regeneration pH (RpH). The higher vigour of ‘Hayward’ somaclones regenerated at high pH seemed to be confirmed in the field. In contrast, the pH selection pressure during regeneration had no clear effect on plant tolerance to lime. For ‘Hayward’, the group of somaclones obtained at pH 5.7 showed at high lime levels higher average AGL and NN than those of plants regenerated at pH 7; while clone 7.5-1, the only surviving somaclone among those obtained at the highest pH, was apparently the most tolerant to lime. The percentage of ‘Tomuri’ somaclones obtained at pH 7.5 that seemed less sensitive to lime was slightly higher than those of somaclones regenerated at pH 5.7 and 7. ‘Tomuri’ and ‘Hayward’ controls were both very sensitive to lime. Some somaclones which had been able to grow at high pH in vitro were also fairly tolerant to lime when cultured in pots and/or in the field, especially ‘Tomuri’ 5.7-5, -6; 7-6, -8, -14 and 7.5-6, and ‘Hayward’ 5.7-5; 7-2, -3, -5 and 7.5-1. The in vitro regeneration and selection methods here described therefore seem useful for creating and selecting new variability in kiwifruit and promising for obtaining plants tolerant to high pH and lime levels in the soil.  相似文献   
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Determination of serum or plasma progesterone (P4) concentrations is important to recognize pregnant and non-pregnant ewes, and also to predict the number of carried lambs. The 2 most common methodologies for the detection of plasma P4 are radioimmunoassay (RIA) and enzyme immunoassay (EIA). RIA is very expensive, and not all laboratories are equipped to perform this test; EIA is commercially available for human use, but only a few companies produce species-specific kits, which are expensive. We verified for ovine plasma a less expensive and easily available ELISA kit (DiaMetra) designed to quantify P4 in humans. Pools of ovine and human plasma were used to compare repeatability, accuracy, sensitivity, and stability of P4 measured by the DiaMetra kit. Repeatability data were within 15%, and accuracy values were ~90% for both plasma matrices. Stability data showed a loss of <20% for freeze–thaw and <30% for 30-d storage. All parameters were acceptable under international guidelines for method validation. The human ELISA kit was used successfully to quantify plasma P4 in 26 ewes during pregnancy until delivery. P4 concentrations were also correlated with the number of carried lambs.  相似文献   
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