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661.
662.
Summary

In a 4×4‐vvk cross‐over study, eight adult cats were given four moist diets containing identical amounts of calcium (13.9 mmol/MJ) but with different ratios of calcium carbonate to calcium chloride, the calcium salts providing half of the total dietary calcium. Increasing amounts of calcium chloride were substituted for equimolar amounts of calcium carbonate. Higher intakes of calcium chloride caused significantly lower pH values in postprandial and 24‐h urine samples. The urinary excretion of ammonium and titratable acid rose with increasing calcium chloride intake. The urinary concentrations of calcium and magnesium were not affected by the type of calcium salt, but the urinary excretion and concentration of phosphorus were significantly depressed when the amount of calcium chloride in the diet was increased. The results are discussed in the context of dietary prevention of and therapy for struvite urolithiasis in cats.  相似文献   
663.
Diploid Solanum tuberosum (tbr), 2n=2x=24,can be crossed with S. verrucosum (ver) only when the latter is used as a pistillate parent but not reciprocally. This conforms to the phenomenon of unilateral incompatibility (UI) where a self-compatible species, like ver (SC) cannot be used as a male parent to cross with a self-incompatible (SI) parent like tbr. Even if ver × tbr hybrids are made, the F1 hybrids possess cytoplasmic male sterility and thus hinder genetic analysis of crossing barriers. Exceptionally, however, some diploid genotypes of tbr (SI) can be used as pistillate parents to cross with ver, and such exceptional tbr clones are called `acceptors'. Repeated backcrossing of acceptors to ver have resulted in male fertile genotypes that possess tbr cytoplasm and ver nucleus. These genotypes were used for the genetic analysis of `acceptance' and UI in thse experiments. It was found that acceptance of ver-pollen by tbr-pistils is based on a dominant gene A that expresses only in the absence of an inhibitor I. In the F1 hybrids, only the S-allele of tbr was expressedbut not that of ver. Concomitant with this observation, it was shown that ver does not produce style-specific S-glycoproteins that are responsible for self-incompatible reaction in diploid potato. Although the the F1 populations were SC, they segregated into SC and SI genotypes giving skewed segregation ratios for this trait. Because of this as well as the disappearance and re-appearance of SC trait in the offspring generations, it was necessary to postulate a more complex interaction between A and I. Models are presented in order to explain acceptance, non-acceptance and the expression of UI. It is concluded that at least four different loci are involved in the expression of UI. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
664.
The present work was conducted to evaluate the efficacy of Trichogramma evanescens (Westwood) in controlling the European grape berry moth Lobesia botrana (Den. & Schiff.) in two vineyards, in El-Beheira and El-Gharbia Governorates, northern Egypt during the 2004 and 2005 seasons. T. evanescens was mass produced on Sitotroga cerealella (Olivier) eggs in National Research Center in Egypt. The horizontal and vertical searching activity of T. evanescens was studied to determine the proper way of distributing the Trichogramma cards in vineyards in 2004. Field experiments were also conducted to evaluate inundative releases of T. evanescens to control L. botrana on large scale in 2005. Parasitism by T. evanescens on L. botrana eggs was greatly affected with the horizontal or vertical distance from the release points. Parasitism reached over 97% and reduction percents of infestation were caused by the pest reached 96.8% in treated plots. A significant increase in the crop was achieved in treated plots. The results showed that the release cards should be distributed in every three grape rows and on height 130–170 cm to obtain good parasitism rates. T. evanescens could be a potential candidate for biological control of L. botrana in vineyards.  相似文献   
665.
As the sustainable forest biomass harvesting process is highly influenced by the terrain, the heterogeneity, and the protection status of the landscape, this study highlights the GIS and Remote Sensing as important scientific tools, assisting in the planning process and integrating the appropriate spatial limitations for an ecological forest biomass extraction in a rational bioenergy utilization framework. This study is focused on the northwest Greece and particularly in the regional unit of Grevena which is part of the Western Macedonia region, the region with the highest unemployment rates in Greece. As the forests in the regional unit of Grevena occupy a significant percentage over half of the regional unit area, the emphasis on the sustainable harvesting and utilization of forest biomass for energy purposes could tackle unemployment rates, enhance the energy autonomy of the remote mountain villages, and reduce the Mediterranean forest fire risk. The spatial data process and the implied spatial limitations unfold a methodology procedure, which is revealing specifically quantified and illustrated results as are emerging progressively the oak forests of the regional unit of Grevena with biomass harvesting capabilities, which do not belong to the Grevena’s protected areas, have accessible slopes and lower diversity index.  相似文献   
666.
667.
668.
The detection of winter SO2 pollution effects on young spruce. A comparison of three methods. The suitability, sensitivity and tediousness of three methods (turbidity-test, peroxidase activity, buffering capacity) were compared for detecting the effect of SO2 pollution in winter on spruce seedlings. Buffering capacity failed to detect a difference between controls and fumigated trees. Turbidity test and peroxidase activity yielded statistically significant differences. The turbidity test is less tedious but also less sensitive than peroxidase activity and its use is restricted to conifers.  相似文献   
669.
670.
The computed tomography (CT) features of tumors involving the nasal cavity and/or paranasal sinuses of 15 horses were reviewed. The 15 tumors included five neuroendocrine tumors/neuroblastomas, two undifferentiated carcinomas, two myxosarcomas, and one each of nasal adenocarcinoma, hemangiosarcoma, chondroblastic osteosarcoma, anaplastic sarcoma, myxoma, and ossifying fibroma. All tumors except the ossifying fibroma were iso- or hypoattenuating relative to masseter muscle. Thirteen of the fifteen tumors exhibited moderate or marked osteolysis of adjacent cortical bone and 14/15 were characterized by destructive changes of the nasal turbinates, nasal septum, and/or infraorbital canal. Ten horses had moderate or marked involvement of the cribriform plate and six had clear intracranial extension of the mass. CT features were compared to radiographic findings for 10 horses. A mass was observed in 10/10 radiographic studies and mass within the caudal maxillary sinus (7/8) and rostral maxillary sinus (6/7) was identified correctly in most horses. The radiographs were least sensitive for identifying masses within the sphenopalatine sinus (0/5), cranium (0/4), and retrobulbar space (1/7) compared to CT. The radiographs also underestimated potential features of malignancy, such as severity of osteolysis or osseous production. While radiographs are a useful screening tool for identification of sinonasal masses, CT provides greater information regarding mass extent, features of malignancy, and important prognostic indicators.  相似文献   
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