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21.
Bioassay-guided fractionation of the EtOAc crude extract from Sicilian almond hulls, a waste material from Prunus dulcis crop, allowed identification of 10 constituents, isolated as pure compounds (1-5, 7, and 10) or unseparable mixtures (5 + 6 and 8 + 9). All compounds were subjected to spectroscopic analysis and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide bioassay on MCF-7 human breast cancer cells. In addition to the main components oleanolic (1), ursolic (2), and betulinic (3) acids, the 2-hydroxy analogues alphitolic (4), corosolic (5), and maslinic (6) acids, as well as the related aldehydes, namely, betulinic (7), oleanolic (8), and ursolic (9), were identified. From a more polar fraction, the beta-sitosterol 3-O-glucoside (10) was also identified. A sample of commercially available betulin (11) was also included in bioassays as further support to a structure-activity relationship study. Betulinic acid showed antiproliferative activity toward MCF-7 cells (GI50 = 0.27 microM), higher than the anticancer drug 5-fluorouracil.  相似文献   
22.
Seeds of wild asparagus (Asparagus acutifolius L.) were treated and compared in this research to investigate seed dormancy class and level involved in this species. Four seed lots were compared: (i) freshly harvested seeds in 2007 (07Fr); (ii) freshly harvested seeds in 2008 (08Fr); (iii) after-ripened (AR) 2007 seeds dry stored in glass jars (ARg); (iv) AR 2007 seeds dry stored in paper bags (ARp). The 07Fr seeds were exposed to (1) chemical scarification combined with gibberellic acid (GA3) levels (0, 200, 400, and 600 mg L−1) and to (2) 28-day moist stratification at 5 and 23 °C, and two sequences of 5/23 °C combined with 0 and 400 GA3 mg L−1 levels, and (3) together to the 08Fr and AR seeds were exposed to 56-day moist stratification at 5, 23, or 5/23 °C. With the 08Fr and AR seed lots this last stratification treatment was combined with 0 or 800 GA3 mg L−1 levels. The dormancy depth of 08Fr (32% germination) was less than 07Fr seeds (2%). The latter after-ripened during dry storage and when stored in glass germinated more (47.5%) than in paper (12%). Stratification for 4 weeks was ineffective in improving germination of 07Fr seeds; when chemically scarified they did not germinate at all. The highest (nearly 70%) and the most rapid and uniform germination were observed for all the lots when they were warm stratified for 56 days. Warm stratification improved germination more than alternate temperature stratification, while cold stratification inhibited germination especially for the 08Fr and ARg lots, thus seeds seem not to have a morphological component to their dormancy. GA3 only improved germination of 07Fr seeds, at a low rate. A. acutifolius seeds fit the characteristics of a non-deep physiological dormancy.  相似文献   
23.
Twenty-three important Ligurian olive accessions corresponding to 16 cultivars were studied using 12 SSR markers and 40 Mediterranean cultivars were included in the study in order to investigate the relationships between Ligurian and Mediterranean germplasm. All SSRs produced polymorphic amplifications. One hundred and forty-nine alleles were found in the 63 accessions analysed. Twenty-two alleles were specific to germplasm from Liguria and of these 12 were unique to single cultivars. Heterozygosity and discriminating power calculated in this regional germplasm were high on average (0.70 and 0.74) and not so much lower than the values in the total sample that includes cultivars from different Mediterranean countries (0.77 and 0.88 respectively). No cases of genetic identities were found between Ligurian and Mediterranean accessions. Several cases of homonyms and synonyms within the Ligurian germplasm were explained. Cluster analysis generally revealed a clear discrimination of the profiles from Liguria and Italy with respect to the cultivars from other Mediterranean countries. Only one Ligurian cultivar, “Negrea”, appeared to have a different origin, grouping with the Mediterranean cultivars.  相似文献   
24.
In an attempt to standardise the determination of biological reference values, the International Federation of Clinical Chemistry (IFCC) has published a series of recommendations on developing reference intervals. The IFCC recommends the use of an a priori sampling of at least 120 healthy individuals. However, such a high number of samples and laboratory analysis is expensive, time-consuming and not always feasible, especially in veterinary medicine. In this paper, an alternative (a posteriori) method is described and is used to determine reference intervals for biochemical parameters of farm animals using an existing laboratory data set. The method used was based on the detection and removal of outliers to obtain a large sample of animals likely to be healthy from the existing data set. This allowed the estimation of reliable reference intervals for biochemical parameters in Sarda dairy sheep. This method may also be useful for the determination of reference intervals for different species, ages and gender.  相似文献   
25.
This paper describes the morphology and distribution of the enteric nervous system (ENS) cells and fibres immunoreactive for choline acetyltransferase (ChAT), neuronal nitric oxide synthase (nNOS), substance P (SP), calcitonin gene-related peptide (CGRP), NF200 kDa (NF200), and S100 protein. The percentages of subclasses of enteric neurons in the total neuronal population were investigated by the use of anti-PGP 9.5 or anti-NSE antibodies.ChAT-IR myenteric plexus (MP) and submucosal plexus (SMP) neurons were 66 ± 7% and 74 ± 15%, respectively, whereas those cells expressing nNOS-IR were 38 ± 7% and 5 ± 1%, respectively. MP and SMP neurons expressing both phenotypes were also present. SP-IR was expressed by 14 ± 13% of MP and 66 ± 8% of SMP neurons whereas CGRP-IR was observed only in the SMP (43 ± 6%). NF200-IR was expressed by 61 ± 15% and 91 ± 10% of the MP and SMP neurons, respectively. The majority of the CGRP-IR SMP neurons expressed also SP-IR. Almost all SP-IR neurons in both the plexuses were cholinergic. The present study quantifies the main neuronal subpopulations of the ENS of the horse ileum; these data might be utilized to understand the neuronal modifications which occur in several gastrointestinal tract disorders.  相似文献   
26.
Many authors have tested puppies' behavior early to detect adult behavioral disorders. Our pilot study aims to investigate puppies' reactivity toward tolerance of new situations and the consistency of behavior between puppy and adult dog. Seven tests (tunnel, direct looking, sudden noise, retrieving buster-ball, problem solving, bowl removal, and approaching) were used to evaluate the reactivity of 32 German shepherd dogs at 5, 7, and 9 months of age. Among these dogs, 17 were chosen by physical and behavioral traits to continue the training program up to adulthood (choice group) and administered the same tests at the age of 2 years. Through the observation of behaviors, the tests aim to assess sociality, exploratory and retrieving tendency, learning ability, playing aptitude, and tendency toward offensive aggression. The behaviors were ranked by degree of reactivity, and ranks were used as scores. The effects of gender and group on the 5- to 9-month reactivity profiles of all the puppies were estimated with a repeated-measures model. In the choice group, the behavior changes from 9 to 24 months and their dependence on gender were estimated with an analogous model. All puppies became more self-confident between 5 and 9 months. At 9 months, behavior was slightly better in males and in the choice group. Between 9 and 24 months, self-confidence, attentiveness, and ability to solve problems and retrieve objects improved, whereas playfulness decrease. Behaviors at 9 and 24 months showed very low variability, which indicated their very high similarity.  相似文献   
27.
28.
An immunoenzymatic method for the quantitative determination of dietary lectin activities employing immobilized glycoproteins was studied. Lectins from wheat germ (WGA), peanut (PNA), and jack bean (ConA) were added to microtiter plates coated with ovalbumin or asialofetuin and quantified by enzyme-linked immunosorbent assay (ELISA) with lectin-specific antibodies. ELISA responses for lectin activity were dose-dependent in the concentration range 30-1000 ng/mL for WGA and 80-1000 ng/mL for both PNA and ConA. Inhibition assays carried out with different saccharides confirmed that the binding of lectins to immobilized glycoproteins was specific. The proposed method is specific and sensitive, allowing the quantitative determination of lectin activities on raw samples by simple dilution of the extracts. Examples of application to wheat germ and roasted peanut extracts are reported.  相似文献   
29.
Samples of six common plant species collected in the old mining areas near Prince George, British Columbia (Canada) and Mount Amiata, Tuscany (Italy) show remarkable similarities in the variation of plant/soil Hg concentration ratio with soil Hg content irrespective of species or other biological differences. In contrast, plants sampled in the geothermally active areas of New Zealand, Hawaii and around Mount St. Helens exhibit more individuality in the concentration ratio to soil Hg relationship, but the relationships are distinctly different from the mine site specimens. This distinction is particularly evident when the same species of Equisetum and Plantago taken from these two different areas are compared. These and other data support the hypothesis that specific local environmental factors strongly influence the accumulation of Hg in plants even when the immediate soil concentrations are the same. Our findings show that some plants contain concentrations of total Hg as high as 5500 to 14000 μg kg?1 (dw).  相似文献   
30.
Journal of Pest Science - Transgenic plants that express double-stranded RNA (dsRNA) targeting vital insect genes have recently emerged as a valuable new tool for pest control. In this study,...  相似文献   
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