An antimony sulfide with a two-dimensional, intersecting system of channels     

Parise JB 《Science (New York, N.Y.)》1991,251(4991):293-294

A novel open antimony sulfide framework of composition [Sb(3)S(5)](-) has been synthesized hydrothermally, in the presence of tetramethyl ammonium ions. Determination of the crystal structure demonstrates that the (Me(4)N)(+) molecules (Me, methyl) occlude a system of intersecting channels at 90 degrees to one another. The three-dimensional framework is assembled from a new building unit, flat s-shaped buckled sheets of edge-linked 4-rings containing Sb(2)S(2) moieties. These are cross-linked in two directions to form the system of channels.  相似文献   

Characterization of an ecto-5'-nucleotidase (EC 3.1.3.5) activity in intact trophozoites of Trichomonas gallinae     

Borges FP  Gottardi B  Stuepp C  Larré AB  Tasca T  De Carli GA  Bonan CD 《Veterinary parasitology》2007,143(2):106-111

This study describes the enzymatic properties of an ecto-5'-nucleotidase in Trichomonas gallinae. The enzyme hydrolyzes nucleoside monophosphates at pH 7.2 and is activated by divalent cations, such as magnesium. Ecto-5'-nucleotidase activity was insensitive to levamisole, tetramisole (alkaline phosphatase inhibitors), and AMPCP (adenosine 5'-[alpha,beta-methylene]diphosphate), an ecto-5'-nucleotidase inhibitor, whereas 0.1mM ammonium molybdate (considered a potent inhibitor of 5'-nucleotidase activity) completely inhibited the enzyme activity. The apparent K(M) (Michaelis constant) and Vmax (maximum velocity) values for Mg2+-AMP were 466+/-57 microM and 3.7+/-0.59 nmolPi/min/10(6) trichomonads, respectively. Considering that trichomonads lack the ability to synthesize purines and pyrimidines de novo, the presence of an ecto-5'-nucleotidase in intact trophozoites of T. gallinae could be important in regulating the extracellular nucleotide levels and generating adenosine, essential for the survival strategies of the parasite.  相似文献   

The synergistic effect of organic acids,phytochemicals and a permeabilizing complex reduces <Emphasis Type="Italic">Salmonella</Emphasis> Typhimurium 1,4,[5],12:i-shedding in pigs     

Jessica Ruggeri  Fabio Foresti  Roberta Pavesi  Alessia Terrini  Francesca Giudici  Diego Padoan  Attilio Corradi  Maria Cristina Ossiprandi  Paolo Pasquali  Giovanni Loris Alborali 《Veterinary research communications》2018,42(3):209-217

Salmonella Typhimurium (including S.Typhimurium 1,4,[5],12:i-) and other enteric pathogens cause acute infection in pigs during the weaning stage, often evolving into chronic infections responsible for the introduction of zoonotic bacteria into the slaughterhouse and thus determining carcass contamination. In addition to being zoonotic hazards, these pathogens are responsible for economic losses in affected farms. Traditionally, antibiotic treatments have been largely administered in order to reduce the infection burden but it favored, as a direct consequence, an increase in the number of multi-drug resistance strains. In order to overcome antibiotic-resistance concerns, new alternative control strategies should be developed. In this context, a blend of organic acids, phytochemicals and a permeabilizing complex, administered in feed (Group A - 459 piglets) or water (Group B – 458 piglets), was tested in field conditions for its capability of reducing Salmonella-infection in weaned piglets of an endemic farm. Data recorded were compared to results of a control group (Group C - 456 piglets). Zootechnical parameters were recorded in all animals, while microbiological, serological and PCR analyses were conducted in 15 piglets for each group. Results demonstrated that additive administered in feed improved animal weight gain (better average daily gain [A.D.G.] and increment), and rapidly reduced Salmonella-shedding in feces. Administration of additive in feed gave better results than in water.  相似文献   

Characterization of Spatial Variability Structure in Three Separate Field Trials on Pesticide Dissipation     

Costantino Vischetti  Mario Businelli  Mauro Marini  Ettore Capri  Marco Trevisan  Attilio A. M. Del Re  Lucia Donnarumma  Elisa Conte  Giancarlo Imbroglini 《Pest management science》1997,50(3):175-182

Experiments were carried out on three Italian farms to assess the degree of spatial variation of pesticide field concentration during treatment and during dissipation trials. Test pesticides were chloridazon and metamitron (both sugar-beet herbicides) applied as a tank mix. The classical statistical technique and geostatistics were used to summarize and evaluate variable spatial data. The results show that the actual values of pesticide concentration for application rate and initial concentration in all three areas are lower than expected, thus indicating that under field conditions only a part of the pesticide reaches the soil during the distribution. The actual values for both herbicides in all three areas expressed as percentage of expected values ranged from 44·1% to 64·2% for application rate and from 40·5% to 99·5% for initial concentration. The coefficient of variation was similar for both pesticides and ranged from 23·8 to 74·1 for application rate, 24·1 and 58·8 for initial concentration and 11·1 and 110·0 for dissipation half-lives. The high variability in application rate and initial concentration could be ascribed to an uneven herbicide distribution, and in dissipation studies to variation in half-lives for the rate of herbicide loss from soil in different parts of the field. Geostatistic analysis indicated little spatial correlation, probably because the sampling sites were widely spaced on the field. In all cases, the data were not sufficient to estimate the range of influence, probably because of the size of the experimental fields and the sampling strategy. © 1997 SCI.  相似文献   

Root Uptake and Xylem Translocation of Pesticides from Different Chemical Classes     

Fernando Sicbaldi  Gian Attilio Sacchi  Marco Trevisan  Attilio A. M. Del Re 《Pest management science》1997,50(2):111-119

A pressure-chamber technique was used to study the root uptake and xylem translocation of some fungicides, herbicides and an insecticide from different chemical classes in detopped soybean roots. Physiological parameters such as K⁺ leakage from roots, K⁺ concentrations in the xylem sap, and protein and ATP levels in the root cells were measured so as to evaluate any potential damage of this technique to the root system. HPLC was used to quantify the compounds in the xylem sap. The pressure-chamber technique has proved useful to study the root uptake and translocation of pesticides, does not damage the root system, and allows one to obtain appreciable volumes of xylem sap that can be analysed directly by HPLC, thus avoiding dependence on the availability of radio-labelled compounds. The concentration of each pesticide in the xylem sap showed a steady-state kinetic profile. Non-linear regression analysis was used to calculate the steady-state concentration and the time required to achieve 50% of the steady-state concentration (TSSC₅₀). TSSC₅₀ was well correlated with log K_ow; the more lipophilic the compound the more time was required to reach the steady-state concentration. The efficiency of translocation was assessed by the transpiration stream concentration factor (TSCF) and a non-linear relationship between TSCF and log K_ow was observed. The highest TSCF values were measured for those compounds with log K_ow values around 3, a lipophilicity value similar to that reported earlier in an analogous experiment with detopped soybean plants but slightly higher than that reported in earlier experiments with intact barley plants. Lower TSCF values were obtained with chemicals with log K_ow values below as well as above 3. © 1997 SCI.  相似文献   

Selective modulation of P-glycoprotein activity by steroidal saponines from Paris polyphylla     

Nguyen VT  Darbour N  Bayet C  Doreau A  Raad I  Phung BH  Dumontet C  Di Pietro A  Dijoux-Franca MG  Guilet D 《Fitoterapia》2009,80(1):39-42

Bio-guided fractionation of the roots of Paris polyphylla (Trilliaceae), based on inhibition of P-glycoprotein-mediated daunorubicin efflux in K562/R7 cell line, led to isolation and identification of the three saponins 3-O-Rha(1-->2)[Ara(1-->4)]Glc-pennogenine, gracillin and polyphyllin D, and the two ecdysteroids 20-hydroxyecdysone and pinnatasterone. These compounds were tested for multidrug reversion on P-glycoprotein (ABCB1) with both drug-selected and transfected cell lines, and also on Breast Cancer Resistance Protein (BCRP/ABCG2). By contrast to a weak efficiency on BCRP, the three saponins displayed significant effects as inhibitors of P-glycoprotein-mediated drug efflux.  相似文献   

Oleuropein-Specific-13-Glucosidase Activity Marks the Early Response of Olive Fruits （Olea europaea） to Mimed Insect Attack     

Antonia Spadafora Silvia Mazzuca Francesca Fiorella Chiappetta Attilio Parise Enzo Perri AnnaMafia Innocenti 《中国农业科学(英文版)》2008,7(6)

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Mediterranean diet in relation to body mass index and waist-to-hip ratio     

Rossi M  Negri E  Bosetti C  Dal Maso L  Talamini R  Giacosa A  Montella M  Franceschi S  La Vecchia C 《Public health nutrition》2008,11(2):214-217

OBJECTIVE: The Mediterranean diet is rich in fat and starch, and hence may be related to overweight. We therefore investigated the relationship between adherence to a Mediterranean diet and body mass index (BMI) and waist-to-hip ratio (WHR). DESIGN AND SETTING: Data were obtained from the control group of a network of case-control studies on cancer conducted in major teaching and general hospitals in four Italian areas between 1991 and 2002. An interviewer-administered validated 78-item food-frequency questionnaire was used to obtain information on the subjects' habitual diet. Information on socio-economic factors, lifestyle habits and anthropometric measures was also collected. A Mediterranean diet score (MDS) was derived on the basis of eight characteristics of the Mediterranean diet. SUBJECTS: Subjects were 6619 patients (3090 men, 3529 women) admitted to hospital for a wide spectrum of acute, non-neoplastic conditions, unrelated to known risk factors for cancer and long-term modifications of diet. RESULTS: In multiple linear regression models adjusted for age, study centre, education, tobacco smoking, occupational physical activity and total energy intake, the MDS was not related to BMI (beta = 0.05 for men and -0.04 for women) or WHR (beta = 0.000 and 0.001, respectively) in both sexes. CONCLUSIONS: Adherence to the major characteristics of the Mediterranean diet is unrelated to BMI and WHR, confirming previous data from Greece and Spain.  相似文献   

An epidemiology study on travel anxiety and motion sickness     

Simona Cannas  Marina Evangelista  Pier Attilio Accorsi  Manuela Michelazzi 《Journal of Veterinary Behavior: Clinical Applications and Research》2010,5(1):25-26

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Admissions test for the degree course in veterinary medicine in Italy, 2005     

Corradi A  Bottarelli E  Bertoli B  Flammini CF 《Journal of veterinary medical education》2007,34(2):99-105

In Italy, access to the degree course in veterinary medicine is regulated each academic year by a government decree that sets the maximum student intake number for each of the 14 existing faculties. Candidates are selected by means of a multiple-choice test on the following subjects: logic and general knowledge, biology, chemistry, physics, and mathematics. Data for the 2005/2006 academic year are presented here. Overall, 4,495 candidates took the test and 1,415 (31.5%) qualified. The questions relating to physics and mathematics were more difficult than those in other subjects (p < 0.001). Logic and general knowledge was the subject in which candidates' knowledge was best. Separate data for each of the 14 Italian faculties are presented, along with the cut-off score for admission. In addition, a "difficulty admission index" has been calculated for each faculty centre.  相似文献