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91.
Road runoff waters are able to convey a number of organic and inorganic pollutants originated by different non-point sources and by the road surface itself. Such pollutants can enter aquatic systems, thus contributing to water and soil contamination. This study was aimed at evaluating the pollutant content in first flush runoff waters from a highway located in Central Italy. A water sampling apparatus was devised able to collect only the first 10 L of runoff water. Water samples were analyzed by atomic absorption spectroscopy, ion chromatography, and gas chromatography-mass spectrometry in order to determine metals, ions, and polynuclear aromatic hydrocarbons, respectively. Soil samples were collected as well for metal and hydrocarbon determination. Results obtained in a field experiment carried out in two different seasons and in two different sites along the highway are reported. The study was extended to water samples collected in a strip of the same road not yet in use. Results obtained showed a temporal and a spatial variability due to the different period rainfall and to sites features, respectively. Within such a variability, a substantial agreement, in terms of order of magnitude, with other studies carried out in European sites was observed.  相似文献   
92.
A sensitive and selective analytical method for the determination of acrolein in heated vegetable oils by liquid chromatographic separation with pulsed electrochemical detection is described. An optimized triple-step pulsed waveform, based on the formation/inhibition of PtOH species on the electrode surface, a consequence of the absence/presence of adsorbing analytes, is described for the sensitive detection of acrolein in acidic medium. Under these optimized experimental conditions the proposed analytical method allowed detection limits of 0.15 microM without pre- or postcolumn derivatization or tedious cleanup procedures. The proposed analytical method was successfully employed for the sensitive determination of acrolein in fresh and heated vegetable oils with good mean recoveries, selectivity, and analytical reproducibility.  相似文献   
93.
OBJECTIVES: To compare the accuracy of two ultrasonographic measurements, inner chorionic cavity diameter and biparietal diameter, for the prediction of parturition date in small and medium size bitches. The effects of litter size and fetal sex ratio on the accuracy of the prediction were also investigated. METHODS: Ultrasonographic examinations were performed on pregnant bitches and, depending on the stage of pregnancy, the inner chorionic cavity diameter and biparietal diameter were measured. The mean value of the data of each structure was calculated and the predicted day of parturition was obtained by the application of equations derived from growth curves we previously developed for different size bitches. RESULTS: The parturition term was predicted with similar accuracy during early gestation, by the measurement of inner chorionic cavity diameter, as well as during late gestation, by the measurement of biparietal diameter. Litter size affected only biparietal diameter accuracy, whereas fetal sex ratio did not influence the estimation of the day of parturition. CLINICAL SIGNIFICANCE: Inner chorionic cavity diameter and biparietal diameter were equally reliable parameters in obtaining a reasonably accurate prediction of parturition date at any gestational period at which a bitch is examined.  相似文献   
94.
Manipulation of starch composition in cereals and particularly in wheat is receiving increasing attention due to recognition of its important role in food and nonfood applications. The amylose/ amylopectin ratio influences the physicochemical properties of starches and nutritional value of derived end products. Identification of the key enzymes involved in the starch biosynthetic pathway has opened new avenues for altering the amylose and amylopectin content in durum and bread wheat. The granule bound starch synthases (GBSSI), or waxy proteins, are the enzymes responsible for amylose synthesis in storage tissues; amylopectin is produced by the concerted action of different enzymes, including starch synthases (SS), branching (SBE), and debranching enzymes (DBE). By altering the level of key enzymes involved in the regulation of starch synthesis, it is possible to generate novel starches with unique functional properties. In this respect, both low and high amylose starches are particularly interesting because they are associated with industrial and processing properties as well as with human health and nutrition. So far, major attention has addressed the manipulation of starch composition in bread wheat, whereas durum wheat has been investigated to a much lesser extent. Approaches currently available to alter amylose/amylopectin ratio and tailor starch composition in durum wheat are presented.  相似文献   
95.
The aim of this study was to determine the efficacy of a concentrated combination of tiletamine–zolazepam [TZ, 0.53 mg/kg body weight (BW)], ketamine (Ket, 0.53 mg/kg BW), and detomidine (Det, 0.04 mg/kg BW) in the immobilization of free-range cattle for clinical procedures. The combination was administered intramuscularly to 53 animals. Anesthesia was reversed with the α2-adrenoceptor antagonist atipamezole. Locoregional anesthesia was provided with lidocaine when required. The TZKD combination induced suitable immobilization for minor surgical procedures or medical treatments. Anesthetic onset was rapid, taking a mean of 6.1 min [standard deviation (SD) 2.8 min]. The duration of anesthesia depended on the time of administration of the antagonist; the animals recovered in the standing position in 12.9 ± 8.9 min after the administration of atipamezole. The quality of anesthesia and analgesia were satisfactory. In conclusion, this TZKD combination can be used for both immobilization and minor surgical procedures in free-range cattle.  相似文献   
96.
The aims were to evaluate the suitability of a non-commercial TRIS-lecithin (LC) extender and the effect of different concentrations of catalase (CAT) on motility, capacitation status (Chlortetracycline-assay) and zona pellucida (ZP) binding capacity of canine spermatozoa stored at +5°C for 4 days. The sperm-rich fractions of the ejaculates of four stud dogs were divided into four aliquots. After centrifugation, sperm pellets were diluted (200 × 106 sperm/ml) in TRIS buffer, citric acid, fructose, antibiotics, supplemented with 20% egg yolk (TRIS-EY) or 0.04% soybean lecithin (TRIS-LC) with CAT (150 or 450 UI/ml) or without CAT, and then preserved at 5°C for 4 days. The results showed that LC is a valid alternative to EY for chilling canine semen, as similar rates of motility, number of uncapacitated spermatozoa and of spermatozoa binding the oocyte ZP were obtained in semen chilled in TRIS-LC or TRIS-EY. Different concentrations of CAT in a TRIS-LC based extender did not improve the quality of semen after chilling. However, a concentration of 150 UI/ml CAT resulted in an increased number of spermatozoa bound to the oocyte ZP, after 4 days of chilling when compared to semen chilled with TRIS-EY and TRIS-LC. In conclusion, an animal protein-free extender with soybean LC, as a replacement of EY, is suitable for 4 days chilling of canine spermatozoa, but the addition of CAT does not improve general semen quality except for a slight effect on sperm-ZP binding.  相似文献   
97.
98.
During the periparturient period, some impairment of immune defences were observed. Reference values for the different non-specific immune parameters in cows are not generally available, thus limiting the application of these parameters in dairy practice. This paper reports the data on the measurements of different parameters in the blood, and explores the possible influence of the herd on the non-specific immune status of the cow. Five herds located in Northern Italy were selected and overall 39 heifers were enrolled in the trial. Blood samples were taken 14 and 7 days before the expected date of calving, then at 7, 14, 21, 28, 45, 60, and 75 days after calving. The parameters assessed were N-acetyl-beta-glucosaminidase (NAGase), lysozyme, nitric oxide, superoxide dismutase, haptoglobin, respiratory burst, and serum protein profile. After calving, a significant decrease of respiratory burst and nitric oxide concentration were observed in comparison with the pre-calving values but not with the post-calving samplings. Total proteins, beta- and gamma-globulins showed a progressive and significant increase in concentration after calving, in comparison with pre-calving values. The results of the study confirmed that a decrease of immune functions can be observed in commercial dairy herds in the first four weeks after calving. The amplitude of this phenomenon is not common to all animals and all herds, suggesting the possibility to reduce the impairment by improved management and genetic selection.  相似文献   
99.
Increased availability of canine embryos would be desirable to develop research and to apply assisted reproductive technologies in the treatment of infertility and in the improvement of reproductive performances in valuable Canids, both domestic and non-domestic. Embryo production through in vitro fertilization and nuclear transfer has been technically achieved in the dog, and the transfer of cloned embryos has recently resulted in the birth of puppies. However, the efficiency of these technologies is still very limited. This is mainly because of the peculiar characteristics of the canine oocyte and the lack of its full acquisition of developmental competence in vitro. This paper discusses the latest results and aspects on which further research should be focused to provide advances in the field.  相似文献   
100.
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