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191.
A hydroalcoholic extract of lime ( Citrus aurantifolia) leaves has been developed in Cuba to be used as a nutritional supplement and phytomedicine in the form of tincture (TLL). A HPLC-PDA-ESI/MS/MS method has been used for the comprehensive analysis of C-glycosyl flavones in TLL. Six C-glycosyl flavones were characterized and, to confirm the proposed structures and to elucidate the nature of the sugar units, a preparative procedure was applied, and isolated compounds were characterized by NMR. Apigenin-6,8-di-C-beta-D-glucopyranoside (vicenin II) (1), diosmetin-6,8-di- C-beta- d-glucopyranoside (2), apigenin-8-C-beta-D-glucopyranoside (vitexin) (3), apigenin-8-C-[alpha-L-arabinopyranosyl-(1-->6)]-O-beta-D-glucopyranoside (4), apigenin-6-C-[alpha-l-arabinopyranosyl-(1-->6)]-O-beta-D-glucopyranoside (5). and apigenin-6-C-beta-D-glucopyranoside (isovitexin) (6) were identified in TLL and quantified by HPLC-PDA. Compounds 4 and 5 were two new arabinosyl derivatives of vitexin and isovitexin. Inhibitor effect of TLL on platelet aggregation induced by physiological agonists of platelets was evaluated in human plasma. TLL inhibited significantly ADP and epinephrine-induced platelet aggregation in a concentration-dependent manner (IC 50=0.40 and 0.32 mg/mL, respectively).  相似文献   
192.
The aim of this study was to investigate how long‐term Mancozeb application to banana plantations affects the occurrence of pollutants in drainage‐channel sediment and water under tropical conditions. We estimated the possible accumulation of Mancozeb's principal metabolite ethylenethiourea (ETU), as well as manganese (Mn) and zinc (Zn) as components in channel sediment and water. We took samples during the tropical‐rainfall season and the low‐rainfall season. For sediment samples, we determined the contents of ETU, Mn, and Zn. For water samples, we determined the concentration of ETU. Additionally, we took water samples from a runnel that is the receiving body of hydraulic flow from the system. In both seasons, ETU in the sediment was near the detection limit (0.01 mg kg–1) and did not show any accumulation. However, Mn in sediment at all sampling sites exceeded the threshold values for aquatic life of 630 mg kg–1 with values between 635 and 7256 mg kg–1. The Zn concentrations in sediment varied from 87 to 190 mg kg–1 and exceeded the threshold values for aquatic life of 98 mg kg–1 at several sites. Furthermore, we determined an accumulation of these heavy metals in the sediments of the banana‐planted zone in comparison with sediments in pasture reference sites. In contrast to the low concentration of ETU in sediment, its concentration in drainage and runnel water (5.9–13.8 μg L–1) exceeded the EU threshold value for drinking water (0.1 μg L–1) by up to nearly 140 times. However, the threshold value for aquatic life was not exceeded. We conclude that long‐term Mancozeb application does lead to a severe accumulation of Mn in sediments and of ETU in surface water. New strategies should be used to control black Sigatoka, including integrated methods of pest control so that long‐term negative effects on the environment can be avoided.  相似文献   
193.
Aquaculture activity has grown remarkably in the last years, crustaceans being the most profitable products because of their high prices. Feeding costs represent a large portion of total operating costs in the aquaculture industry. In this context, the objective of the present study was to evaluate the effect of food restriction on the reproductive performance of redclaw crayfish Cherax quadricarinatus. Females at the onset of sexual maturity were stocked with males and were fed daily a formulated diet at 1.5% (control group) and 0.5% (restricted group) of their mean weight. The experimental period lasted 105 days. The percentage of ovigerous females and broods successfully hatched tended to be higher in restricted females compared with control females, but egg volume and weight did not differ between both experimental groups. However, the lipid concentration of rematuring ovaries was lower in restricted females than control females, suggesting that food restriction affects the amount of reserves transferred to the ovaries during vitellogenesis. The nutritional state of females was independent of the amount of food provided, as reflected by similar growth parameters and biochemical composition of the hepatopancreas in control and restricted females. Based on these results, we conclude that it is possible to reduce the feeding rate of C. quadricarinatus females to one‐third of its original value without affecting their reproductive performance and somatic growth, at least for a 105‐day period. This finding provides a useful tool for commercial producers to decrease production costs and improve water quality in culture systems.  相似文献   
194.
A 10‐year‐old male domestic shorthaired cat was presented with chronic diarrhea unresponsive to treatment. Laboratory testing identified hyperglobulinemia and mild nonregenerative anemia, and nongastrointestinal causes of diarrhea were ruled out. Gastrointestinal endoscopy and biopsy were performed and disclosed diffuse generalized granulomatous and lymphoplasmocytic inflammatory reaction in all segments of gastrointestinal tract evaluated, with numerous Leishmania spp. amastigotes within the cytoplasm of macrophages. The organism also was detected in spleen and bone marrow and Leishmania spp. serology was positive (immunofluorescence assay 1 : 160). A diagnosis of granulomatous enteritis secondary to leishmaniosis was made. Gastrointestinal signs resolved after treatment with allopurinol and a dietary supplement of nucleotides and active hexose‐correlated compounds (N‐AHCC), but seropositivity and gammopathy persisted 8 months later. The cat died of unrelated causes after an additional 3 months and permission for necropsy was not granted. Leishmaniosis as a cause of chronic diarrhea has not been reported previously in cats and should be considered in endemic areas in cats with chronic gastrointestinal signs.  相似文献   
195.
Codium bernabei is a green alga that grows on Chilean coasts. The composition of its structural polysaccharides is still unknown. Hence, the aim of this work is to isolate and characterize the hot water extracted polysaccharide fractions. For this purpose, the water extracts were further precipitated in alcohol (TPs) and acid media (APs), respectively. Both fractions were characterized using different physicochemical techniques such as GC-MS, GPC, FTIR, TGA, and SEM. It is confirmed that the extracted fractions are mainly made of sulfated galactan unit, with a degree of sulfation of 19.3% (TPs) and 17.4% (ATs) and a protein content of 3.5% in APs and 15.6% in TPs. Other neutral sugars such as xylose, glucose, galactose, fucose, mannose, and arabinose were found in a molar ratio (0.05:0.6:1.0:0.02:0.14:0.11) for TPs and (0.05:0.31:1.0:0.03:0.1:0.13) for ATs. The molecular weight of the polysaccharide samples was lower than 20 kDa. Both polysaccharides were thermally stable (Tonset > 190 °C) and showed antioxidant activity according to the ABTS•+ and DPPH tests, where TPs fractions had higher scavenging activity (35%) compared to the APs fractions. The PT and APTTS assays were used to measure the anticoagulant activity of the polysaccharide fractions. In general, the PT activity of the TPs and APs was not different from normal plasma values. The exception was the TPs treatment at 1000 µg mL−1 concentration. The APTTS test revealed that clotting time for both polysaccharides was prolonged regarding normal values at 1000 µg mL−1. Finally, the antitumor test in colorectal carcinoma (HTC-116) cell line, breast cancer (MCF-7) and human leukemia (HL-60) cell lines showed the cytotoxic effect of TPs and APs. Those results suggest the potential biotechnological application of sulfate galactan polysaccharides isolated from a Chilean marine resource.  相似文献   
196.
Abstract

The ‘FHIA-18’ hybrid banana is an alternative for producers as it is resistant to Black Sigatoka and Panama disease. However, few studies report the nutritional requirement of this hybrid, especially phosphorus. It is known that the efficiency of phosphorus use can be improved, reducing the need for application, depending on the genotype cultivated. Therefore, this study aimed to evaluate the yield and mineral nutrition of ‘FHIA-18’ hybrid banana on phosphate fertilization. A banana orchard with the cultivar ‘FHIA-18’ was conducted on a Typical Red Latosol. Then, triple superphosphate fertilizer was applied on plants at 0, 20, 30, 40, 50, and 60?kg ha?1?year?1, over three productive seasons. At the time of flowering the macro and micronutrient contents of the leaves were evaluated. Subsequently, the nutrient contents of the fruits were evaluated. For this, fruit pulp samples from the third and fourth hands were collected. In addition, yield was estimated considering cluster mass and plant density. The following dose 36?kg ha?1 of P2O5 year?1 increased the content of phosphorus in the leaf, despite that banana hybrid cultivar FHIA 18 demanded 50% of the recommended fertilizer to achieve its maximum yield (29.4 t ha?1?year?1). Phosphate fertilization promoted significant changes in P, Ca, Cu, and Zn contents of leaves and fruits. Therefore, it is concluded that the mineral nutrition of banana ‘FHIA-18’ is affected by phosphate fertilization, as well as requiring less P than recommended to achieve higher yield.  相似文献   
197.
The interactions between six insecticides (methiocarb, formetanate, acrinathrin, deltamethrin, methamidophos and endosulfan) and three potential synergists (piperonyl butoxide (PBO), S,S,S-tributyl phosphorotrithioate (DEF) and diethyl maleate (DEM)) were studied by topical exposure in strains selected for resistance to each insecticide, and in a susceptible strain of Frankliniella occidentalis (Pergande). In the susceptible strain PBO produced appreciable synergism only of formetanate, methiocarb and methamidophos. Except for endosulfan, PBO synergized all the insecticides to varying degrees in the resistant strains. A very high level of synergism by PBO was found with acrinathrin, which reduced the resistance level from 3344- to 36-fold. PBO slightly synergized the carbamates formetanate (4.6-fold) and methiocarb (3.3-fold). PBO also produced a high synergism of deltamethrin (12.5-fold) and methamidophos (14.3-fold) and completely restored susceptibility to both insecticides. DEF did not produce synergism with any insecticide in the resistant strains and DEM was slightly synergistic to endosulfan (3-fold). These studies indicate that an enhanced detoxification, mediated by cytochrome P-450 monooxygenases, is the major mechanism imparting resistance to different insecticides in F occidentalis. Implications of different mechanisms in insecticide resistance in F occidentalis are discussed.  相似文献   
198.
Seroprevalence of Toxoplasma gondii was tested for in 585 cats in different regions of Spain. Sera were tested by the indirect immunofluorescence antibody test (IFAT). Specific antitoxoplasma IgG (IFAT titer>or=1/80) were found in 189 of 585 (32.3%): 117 of 317 (36.9%) stray cats, 16 of 48 (33.3%) farm cats and 56 of 220 (25.5%) household cats. The overall prevalence was significantly higher in stray groups (36.4% of 365) than in household cats (25.5% of 220), higher in adult cats (>6 months old, 36.8% of 443) than in juvenile cats (<6 months old, 13.9% of 101), and higher in male stray cats (45.3% of 128) than in female stray cats (32% of 153). Prevalence of intestinal parasites was also analysed by a routine coprological method in 382 of the 585 cats. Intestinal parasites were found in 107 faecal samples (28%): 76 of 231 (32.9%) stray cats, 14 of 48 (29.2%) farm cats and 17 of 103 (16.5%) household cats. T. gondii oocysts were not found in any faecal samples analysed. The following prevalences of other intestinal parasites were found: Toxocara cati (18.3%), Toxascaris leonina (1.3%), Ancylostoma sp. (1%), Capillaria spp. (1.3%), Aelurostrongylus abstrusus (1%), Taenia like (3.7%), Dipylidium caninum (2.6%) and Cystoisospora spp. (6.3%).  相似文献   
199.
Right ventricular myocardial (RVM) motion is poorly documented. The objective of this study was to determine the variability of RVM velocities by tissue Doppler imaging (TDI) in healthy dogs (study 1), to analyze RVM motion in a large healthy canine population (study 2), and to compare the results with those obtained for the left ventricular free wall. Six healthy Beagle Dogs were monitored in study 1, and 64 healthy dogs of 14 different breeds were monitored in study 2. Velocities were recorded in 2 segments (basal and apical) of the right and left myocardial walls. In study 1, 36 TDI examinations were performed for 4 days, whereas a single TDI examination was performed on each dog in study 2. All velocity profiles included 1 positive systolic wave and 2 negative diastolic waves. The lowest intraday and interday coefficient of variation values of the right TDI variables were observed at the base (3.5-16.1%). The variability of the right apical velocities was much higher, with most coefficient of variation values > 15%. RVM velocities were higher in the basal than in the apical segments (P < .001) and were higher than the left velocities of the corresponding segment (P < .01). Body weight and breed had an effect on only a few right and left TDI variables. TDI provides a repeatable and reproducible method for evaluating basal RV function in the dog. These data also demonstrate the heterogeneity of the myocardial velocities between the left and the right ventricles and between the base and the apex.  相似文献   
200.
OBJECTIVE: To measure the radial and longitudinal velocities of several myocardial segments of the left ventricular wall by use of tissue Doppler imaging (TDI) in healthy cats and determine the repeatability and reproducibility of the technique. ANIMALS: 6 healthy cats. PROCEDURE: 72 TDI examinations were performed on 4 days by the same trained observer. Radial parameters included left endocardial and epicardial myocardial velocities. Longitudinal parameters included left basal, middle, and apical myocardial velocities. RESULTS: All velocity profiles had 1 positive systolic wave (S) and 2 negative diastolic waves (E and A). Myocardial velocities were higher in the endocardial than epicardial segments during the entire cardiac cycle (systolic wave S, 4.4 +/- 0.82 and 1.9 +/- 0.55; diastolic wave E, 9.7 +/- 1.70 and 2.2 +/- 0.74; and diastolic wave A, 5.1 +/- 1.56 and 1.4 +/- 0.76, respectively). Velocities were also higher in the basal than in the apical segments (systolic wave S, 4.7 +/- 0.76 and 0.2 +/- 0.11; diastolic wave E, 9.7 +/- 1.36 and 0.5 +/- 0.17; and diastolic wave A, 3.7 +/- 1.51 and 0.2 +/- 0.13, respectively). The lowest within-day and between-day coefficients of variation were observed in endocardial segments (8.2% and 6.5% for systolic wave S and diastolic wave E, respectively) and in the basal segment in protodiastole (5.5%). CONCLUSIONS AND CLINICAL RELEVANCE: Repeatability and reproducibility of TDI were adequate for measurement of longitudinal and radial left ventricular motion in healthy awake cats. Validation of TDI is a prerequisite before this new technique can be recommended for clinical use.  相似文献   
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