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51.
Two kinds of surveys on marine environment quality were carried out along the Neapolitan Bay from the winter 1977 to 1980. The first was a general investigation along 60 km of coast, embracing several municipalities. Its purpose was to identify the most consistently polluted areas. The second one was a more limited but prolonged monitoring along about 12 km of coast entirely included in the municipality of Naples. At the beginning of this latter inspection two fecally contaiminated areas were found. These showed an increase in pollution during summer. However during the three years of surveillance a general improvement of the water quality was observed, perhaps due to the use of undersea pipes for the discharge of sewage far from the coast. As a consequence in the summer of 1980, 78% of the sampling points exihibited values ofEscherichia coli below limits prescribed in the Italian standard for bathing water (100E. coli/100 ml), while only 38% of the stations in the summer of 1978 could be considered suitable for bathing.  相似文献   
52.
Summary In alfalfa (Medicago sativa) regeneration is genotype-specific. In order to study the genetic control of somatic embryogenesis and to constitute a synthetic cultivar characterized by its high regeneration ability, 2 embryogenic plants selected from the cv. Adriana were selfed, intercrossed and also crossed in both directions with 5 non-embryogenic genotypes of the same cultivar.Progenies of all crosses were scored for their regeneration ability and results indicate that somatic embryogenesis is under the control of 2 dominant loci. However some non-embryogenic genotypes prevent regeneration when crossed with embryogenic ones and this characteristic is not under the control of a single dominant gene.When plants chosen for their capacity to regenerate within F1 and S1 progenies were freely intercrossed the regeneration efficiency dropped to 2% (1 plant out of 50). This result indicates that if the genetic background of the population is changed the regeneration is greatly affected and therefore some other mechanism could play a role in determining plant regeneration.  相似文献   
53.
F. Pupilli    S. Businelli    F. Paolocci    C. Scotti    F. Damiani  S. Arcioni 《Plant Breeding》1996,115(2):106-112
Seven widely-cultivated alfalfa varieties and three ecotypes adapted to Central Italy were used to evaluate the extent of polymorphism in that species. Twenty plants per accession were analysed with 16 RFLP probes combined with three restriction enzymes (48 probe/enzyme combination in total) and the data were used to compute the Nei's similarity index taken as a measure of inter- and intra-population RFLP variability. The varieties were, in general, more homogeneous than the ecotypes and the cultivars ‘Adriana’ and ‘Florida’ could be differentiated more easily than the others. Few accession-specific hybridizing fragments were scored and seven populations could be distinguished from the others on the basis of significant differences in the frequencies of specific fragments. The DNA of plant populations of several sizes was bulked and the ability to detect a given fragment in pooled samples was related to the fraction of plants having that fragment among the plants forming the bulk. The results are discussed with special emphasis on the practical utilization of RFLPs for varietal identification.  相似文献   
54.
Wood modification with siloxanes bearing amino groups with copper-linking function was carried out by a sol–gel process. Tetraethoxysilane (TEOS) and 3-aminopropyltriethoxysilane (APTES) were the main components. Two different procedures were followed: a two-step process (impregnation with the TEOS/APTES mixture followed by dipping into a copper sulphate solution) and a one-step process (impregnation with a homogeneous sol mixture of TEOS, APTES and copper (II) chloride). The obtained materials were characterized by infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy dispersive X-ray microanalysis. The determination of copper content before and after leaching was performed by atomic absorption spectroscopy. The efficacy against the brown rot fungus Coniophora puteana was tested by an accelerated procedure. SEM analyses showed that silicon penetrated into wood, while copper is effectively drawn into wood only in the one-step treatment. Copper fixation to the silica gel proved to be adequately strong. Both sol–gel treatments gave good protection against Coniophora puteana.  相似文献   
55.
The chemical composition of the volatile fractions from leaves of three Olea europaea L. cultivars (Leccino, Frantoio, and Cipressino) harvested at two different times of the year were examined by GC and GC-MS. The results showed a high content of aliphatic aldehydes in the three cultivars during both harvesting periods and an increase of (E)-2-hexenal (an aldehyde with high antimicrobial properties) percentage from July to November.  相似文献   
56.
The morphology and length of roots and shoots of tomato (Lycopersicon esculentum Mill.) seedlings grown on a nutrient medium for fourteen days in a controlled environment chamber were apparently not affected, whereas the dry matter content of roots was significantly enhanced when 200 mg L?1 of humic acid (HA) isolated from either a non-amended soil or a sewage-sludge-amended soil was present in the nutrient medium. In contrast, the HA-like fraction isolated directly from the sewage sludge caused, under the same conditions, extensive alterations of tomato morphology and a significant reduction of the length and dry weight of both shoots and roots. The presence in the nutrient medium of the herbicides alachlor or imazethapyr at concentrations of 1 and 0.01 mg L?1, respectively, caused a marked decrease of tomato root and shoot length and dry weight. Differently, the herbicide rimsulfuron at a concentration of 0.01 mg L?1 produced a slight decrease in shoot and root length and a slight increase in their dry weight. A combination of 200 mg L?1 soil HA and each of the herbicides alachlor, rimsulfuron and imazethapyr at concentrations of 1, 0.01 and 0.01 mg L?1, respectively, in the nutrient medium attenuated the growth depression of tomato shoots and roots observed in the presence of the herbicide alone. However, the simultaneous presence of sewage sludge HA and any herbicide in the nutrient solution caused negative synergistic effects on tomato growth. The volume of nutrient solution and the amount of electrolytes taken up by tomato plants during the growth experiments correlated highly significantly with the total plant dry weight. Tomato seedlings induced a pH decrease in the nutrient medium in all treatments except in those where sludge-HA was present, either alone or in combination with any herbicide.  相似文献   
57.
An automated on-line solid-phase extraction-liquid chromatography-electrospray tandem mass spectrometry (SPE-LC-ESI-MS/MS) method was developed for the determination of ochratoxin A (OTA) in alcoholic beverages. Mean recoveries for wine and beer were, respectively, 75 and 82%. Detection was achieved in negative ionization with a Q TRAP mass spectrometer operating in multiple-reaction monitoring (MRM) mode or enhanced product ion (EPI) mode, using the third quadrupole as linear ion trap. The MRM mode turned out to be more sensitive; the method allowed accurate determination of OTA in the range of 0.01-25 ng mL(-1) using external calibration. Within-day and between-day relative standard deviation percentages were <6.2 and <9.1%, respectively. In EPI mode, fragmentation spectra at the limit of quantification (0.03 ng mL(-1)) and good linearity could be obtained. Application of the method (MRM mode) to the analysis of several wine and beer samples purchased in local stores revealed OTA levels in the ranges of 0.03-1.44 ng mL(-1) for wines and 0.02-0.14 ng mL(-1) for beers.  相似文献   
58.
To learn more about predispositions for, signs, and progression of canine thunderstorm phobia, a survey for owners was posted on the Internet. Questions addressed signalment, age of onset, behavior during storms, and treatments tried. Sixty-nine responses were received. Herding dogs and herding crossbreeds accounted for the majority of dogs. Seventeen of 41 dogs with a known age of onset began exhibiting thunderstorm phobia <1 year of age. Various characteristic responses of dogs to storms were described. Improved knowledge of the demographics of thunderstorm phobia, its development, and presentation will assist in understanding the genesis and progression of the condition.  相似文献   
59.
A 3-month-old female degu (Octodon degus) was presented because blood was noticed in its cage. On physical examination, firm masses were palpable within the caudal abdomen and traces of blood appeared to be coming from the patient’s vaginal opening. Radiographic images showed areas of ill-defined mineralization within the uterus, consistent with fetus formation. Three fetuses could be identified. Ultrasound examination of the degu failed to confirm viable fetal heartbeats. Pregnancy failure with fetal death was suspected. Overnight 1 fetus was passed, but medical therapy with oxytocin failed to induce delivery of the 2 remaining fetuses by the following morning. The degu was therefore anesthetized, an ovariohysterectomy was performed, and the patient made an uncomplicated recovery. Histopathological examination of the fetuses failed to identify any abnormalities. In the uterus, histology confirmed a minimal to mild diffuse, chronic active endometritis. The definitive cause of fetal death was not identified.  相似文献   
60.
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