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11.
Plant Foods for Human Nutrition - Silver linden (Tilia tomentosa Moench, TtM) flowers possess several health-promoting properties, especially at the neurological level, such as intestinal...  相似文献   
12.
Plant Foods for Human Nutrition - Complementary feeding starts at around six months of age because neither breast milk nor formula assure the proper nutrition of infants. Therefore, along...  相似文献   
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The shortfin silverside Chirostoma humboldtianum has been considered for culture in Mexico, but success has been limited by a poor knowledge of its early development. First synthesis of the early development of the shortfin silverside is presented to determine conditions suitable for rearing. Brooder maturation was induced through photothermal cycles. C. humboldtianum ova were fertilized in vitro. The eggs were incubated in reconstituted water (160-180 mg/L CaCO3) at 18 °C and 5 gm of NaCl per litre. During the hatching day, 300 shortfin silversides were stocked and followed up until metamorphosis in order to establish the timing of exogenous feeding, changes in food type, growth and development during critical periods for survival, according to the theory of saltatory ontogeny. Free embryos hatched 12 days after fertilization at 18 °C. First critical point for survival is the beginning of exogenous feeding. Free embryos started mixed feeding on day four of post-hatching (dph), point of no-return was presented towards the end of mixed feeding on 6 dph, larval period began at six (dph) when the anus is opened, and metamorphosis to juvenile was presented at 65 dph with a SL of 19.34 ± 2.28 mm, when scales and fins were well developed. Differences in growth between periods were detected: free embryos growth slower than larvae but mouth size depicted a larger growth rate in the former. Cephalic length and mouth size were negatively related to standard length in embryos and larvae. Mouth size was positively related to cephalic length in free embryos but negative in larvae. Results suggest that during the free embryo phase, growth priorities are directed to the development of apparatuses and systems; whereas, during the larval period, energy is directed to growth in length, mouth size and development of fins, which allows them to increase their swimming velocity, grants them a greater capacity to obtain exogenous food and, in consequence, increases fitness for survival.  相似文献   
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The feeding habits of soil mesofauna have been a mystery for decades, and depending on the methods used, different degrees of feeding specialisation have been observed. A new way to study the almost unknown feeding habits of soil mesofauna e.g. oribatid mites is to use PCR-based techniques. When applying PCR on these small organisms, the low amount of ingested DNA can cause problems. Even more important is to certify that the amplified DNA does not originate from body-surface contamination. The aim of this study was to analyse if washing of the body surface combined with PCR can be a successful approach when identifying the food ingested by fungivorous mites. The method was developed in a laboratory system where we used the oribatid mite Archegozetes longisetosus as a model organism due to its relatively short life cycle and ease of laboratory culturing. The results demonstrated that surface contamination is a serious problem. Both washing and dissection was needed to remove surface contamination on such small organisms. To get a reliable result the samples also had to contain at least five pooled guts, but preferably ten. This is the first step towards a successful use of PCR-based methods to study natural feeding habits of species most likely contaminated on the body surface. When modified for field conditions, the results obtained by this method have a high potential to answer many questions about the animals feeding habits, and their functional role in the soil.  相似文献   
15.
Phospholipase A(2)(PLA(2)) enzymes are considered the primary source of arachidonic acid for cyclooxygenase (COX)-mediated biosynthesis of prostaglandins. Here, we show that a distinct pathway exists in brain, where monoacylglycerol lipase (MAGL) hydrolyzes the endocannabinoid 2-arachidonoylglycerol to generate a major arachidonate precursor pool for neuroinflammatory prostaglandins. MAGL-disrupted animals show neuroprotection in a parkinsonian mouse model. These animals are spared the hemorrhaging caused by COX inhibitors in the gut, where prostaglandins are instead regulated by cytosolic PLA(2). These findings identify MAGL as a distinct metabolic node that couples endocannabinoid to prostaglandin signaling networks in the nervous system and suggest that inhibition of this enzyme may be a new and potentially safer way to suppress the proinflammatory cascades that underlie neurodegenerative disorders.  相似文献   
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A comparison of gene content and genome architecture of Trypanosoma brucei, Trypanosoma cruzi, and Leishmania major, three related pathogens with different life cycles and disease pathology, revealed a conserved core proteome of about 6200 genes in large syntenic polycistronic gene clusters. Many species-specific genes, especially large surface antigen families, occur at nonsyntenic chromosome-internal and subtelomeric regions. Retroelements, structural RNAs, and gene family expansion are often associated with syntenic discontinuities that-along with gene divergence, acquisition and loss, and rearrangement within the syntenic regions-have shaped the genomes of each parasite. Contrary to recent reports, our analyses reveal no evidence that these species are descended from an ancestor that contained a photosynthetic endosymbiont.  相似文献   
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Irrigation plays a fundamental role in world food provision but, to date, it has performed below expectations in Sub-Saharan Africa. The present study assesses and diagnoses the performance of 22 small and medium size community-managed irrigation schemes, mainly devoted to rice production, in different locations along the Mauritanian banks of the Lower Senegal River. The evaluations followed the Rapid Appraisal Process in which semi-structured interviews were held with representatives of the Cooperatives’ Boards in charge of each scheme to obtain information about the organisation of the cooperative, land tenure, irrigation system and organization, cropping pattern and soils. Additionally, for each irrigation scheme, the water-delivery service was characterized by making qualitative and comparative observations during field inspections; the pumping station's performance was diagnosed by a local specialist; the discharge at the head of the system was measured; daily irrigation time was recorded; and crop yields were determined by plot sampling. Then a set of performance indicators was computed. Water delivery capacity referred to irrigated areas was insufficient in a third of the schemes, and this insufficiency was exacerbated by poor maintenance. Irrigation intensity in habilitated areas was rather low being less than 0.66 in 50% of the schemes. The average productivity of land, irrigation water, and fuel (3.38 t ha−1, 0.30 kg m−3 and 2.37 kg kWh−1, respectively) were well below potential.  相似文献   
18.
ObjectiveTo test if the addition of butorphanol by constant rate infusion (CRI) to medetomidine–isoflurane anaesthesia reduced isoflurane requirements, and influenced cardiopulmonary function and/or recovery characteristics.Study designProspective blinded randomised clinical trial.Animals61 horses undergoing elective surgery.MethodsHorses were sedated with intravenous (IV) medetomidine (7 μg kg?1); anaesthesia was induced with IV ketamine (2.2 mg kg?1) and diazepam (0.02 mg kg?1) and maintained with isoflurane and a CRI of medetomidine (3.5 μg kg?1 hour?1). Group MB (n = 31) received butorphanol CRI (25 μg kg?1 IV bolus then 25 μg kg?1 hour?1); Group M (n = 30) an equal volume of saline. Artificial ventilation maintained end-tidal CO2 in the normal range. Horses received lactated Ringer’s solution 5 mL kg?1 hour?1, dobutamine <1.25 μg kg?1 minute?1 and colloids if required. Inspired and exhaled gases, heart rate and mean arterial blood pressure (MAP) were monitored continuously; pH and arterial blood gases were measured every 30 minutes. Recovery was timed and scored. Data were analyzed using two way repeated measures anova, independent t-tests or Mann–Whitney Rank Sum test (p < 0.05).ResultsThere was no difference between groups with respect to anaesthesia duration, end-tidal isoflurane (MB: mean 1.06 ± SD 0.11, M: 1.05 ± 0.1%), MAP (MB: 88 ± 9, M: 87 ± 7 mmHg), heart rate (MB: 33 ± 6, M: 35 ± 8 beats minute?1), pH, PaO2 (MB: 19.2 ± 6.6, M: 18.2 ± 6.6 kPa) or PaCO2. Recovery times and quality did not differ between groups, but the time to extubation was significantly longer in group MB (26.9 ± 10.9 minutes) than in group M (20.4 ± 9.4 minutes).Conclusion and clinical relevanceButorphanol CRI at the dose used does not decrease isoflurane requirements in horses anaesthetised with medetomidine–isoflurane and has no influence on cardiopulmonary function or recovery.  相似文献   
19.
The objective of the present study was to determine the prevalence of Toxoplasma gondii antibodies from slaughter sows and from pigs raised at an indoor and an outdoor swine farm. Serum samples were obtained from 230 slaughter sows belonging to 83 farms distributed in 5 provinces. Blood samples were collected monthly from pigs of different ages from an intensive management indoor farm (farm 1). A cross-sectional study was carried-out from an outdoor farm (farm 2). All sera were tested for T. gondii antibodies by the modified agglutination test (MAT), using formalin-fixed tachyzoites as antigen. An antibody titer > or =1:25 was considered positive. Antibodies to T. gondii were detected in 87 (37.8%) of 230 sows sera. Distribution among provinces was: 37.1% from Santa Fe, 62.8% from Buenos Aires, 3.3% from San Luis, 58.7% from La Pampa and 24% from Córdoba. Four of 88 (4.5%) serum samples from farm 1 had antibodies to T. gondii and none of the negative pigs seroconverted. However, 45 of 112 samples from farm 2 were positive (40.2%) with the following distribution: sows 100%; nursery 40%; growers 13.8% and fatteners 20%. It is concluded that the prevalence of T.gondii antibodies among sows seems to be quite variable. T. gondii prevalence was related to the facilities and management of the farm.  相似文献   
20.
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