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71.

Introduction  

Perfluorinated compounds (PFC) are toxic and bioaccumulative compounds that are ubiquitous in the environment. It is important to develop effective techniques to remove PFC from water. This study is the first to investigate sorption of PFC to activated carbon (AC) at environmentally relevant nanogram per liter concentrations.  相似文献   
72.
The immune responsiveness to infectious bursal disease virus (IBDV) in four native and crossbred chicken lines was compared. ELISA IBDV antibody titers in hen serum samples, yolk from matched eggs and sera from matched 1-day-old chicks from each chicken line with an identical vaccination program were measured, and plotted. There was considerable variation between lines in the measured IBDV specific antibodies, in vaccinated parent hens and in the amounts of inherited maternally derived antibodies in both yolk and progeny chicks. Differences in ratios of the inherited antibody level from hen to 1-day-old chicks were also found among different chicken lines. Breed differences in regressions of IBDV antibody levels in yolk to that of hen or progeny chicks' sera were also found, so prediction of serum titer of hen and/or progeny chicks from yolk are varied among chicken lines.  相似文献   
73.
Empathy is thought to be unique to higher primates, possibly to humans alone. We report the modulation of pain sensitivity in mice produced solely by exposure to their cagemates, but not to strangers, in pain. Mice tested in dyads and given an identical noxious stimulus displayed increased pain behaviors with statistically greater co-occurrence, effects dependent on visual observation. When familiar mice were given noxious stimuli of different intensities, their pain behavior was influenced by their neighbor's status bidirectionally. Finally, observation of a cagemate in pain altered pain sensitivity of an entirely different modality, suggesting that nociceptive mechanisms in general are sensitized.  相似文献   
74.
Fish Physiology and Biochemistry - The trials of finding non-conventional and alternative aquafeed ingredients are increasing. In this sense, this study evaluated the influence of coconut oil on...  相似文献   
75.
In Egypt, continuous circulation of highly pathogenic avian influenza (HPAI) H5N1 viruses of clade 2.2.1 in vaccinated commercial poultry challenges strenuous control efforts. Here, vaccine-derived maternal AIV H5 specific immunity in one-day old chicks was investigated as a factor of vaccine failure in long-term blanket vaccination campaigns in broiler chickens. H5 seropositive one-day old chicks were derived from breeders repeatedly immunized with a commercial inactivated vaccine based on the Potsdam/H5N2 strain. When challenged using the antigenically related HPAIV strain Italy/98 (H5N2) clinical protection was achieved until at least 10 days post-hatch although virus replication was not fully suppressed. No protection at all was observed against the Egyptian HPAIV strain EGYvar/H5N1 representing a vaccine escape lineage. Other groups of chicks with maternal immunity were vaccinated once at 3 or 14 days of age using either the Potsdam/H5N2 vaccine or a vaccine based on EGYvar/H5N1. At day 35 of age these chicks were challenged with the Egyptian HPAIV strain EGYcls/H5N1 which co-circulates with EGYvar/H5N1 but does not represent an antigenic drift variant. The Potsdam/H5N2 vaccinated groups were not protected against EGYcls/H5N1 infection while, in contrast, the EGYvar/H5N1 vaccinated chicks withstand challenge with EGYvar/H5N1 infection. In addition, the results showed that maternal antibodies could interfere with the immune response when a homologous vaccine strain was used.  相似文献   
76.
This retrospective study evaluated the use of lomustine as a rescue agent for 39 cases of resistant feline lymphoma. Parameters assessed included lymphocyte cell size, number of previous chemotherapy drugs and number of previous chemotherapy protocols received, time from lymphoma diagnosis to initiation of lomustine therapy, body weight and anatomic location of lymphoma. Cell size, number of previous chemotherapy drugs, number of previous chemotherapy protocols and anatomic location were all significant prognostic factors for the progression-free interval. Twenty-one cats (54%) received more than one dose of lomustine. The overall median progression-free interval (MPFI) was 39 days (range 7-708 days). The MPFI for large versus small and intermediate cell lymphomas was 21 versus 169 days, respectively. The MPFI for gastrointestinal versus non-gastrointestinal lymphomas was 180 versus 25.5 days, respectively. Lomustine has an acceptable efficacy and safety for use as a rescue agent in feline lymphoma.  相似文献   
77.
Ergosterol and the phospholipid fatty acid (PLFA) 18:2ω6,9 are frequently used as fungal biomarkers in studies on soils, and in accordance with the ideal for biomarkers of microorganisms they are thought to turn over rapidly after cell death and lysis. These biomarkers should also show the same patterns and responses to perturbations of the studied system. Here, I report strong correlations, in natural boreal forests of contrasting fertility, between free ergosterol and PLFA 18:2ω6,9 (r=0.821, P=0.007, n=9). Surprisingly, ergosterol, but not PLFA 18:2ω6,9, appears non-responsive to both large-scale tree girdling, which interrupts tree belowground C allocation to ectomycorrhizal fungi, and to long-term N-loading, which may have negative effects on both mycorrhizal and saprotrophic fungi. These results, therefore, question the use of ergosterol to monitor effects of soil perturbations on fungi in the field, but do not put into question the use of the biomarker in natural forest ecosystems.  相似文献   
78.
Children with Cerebral Palsy (CP) often have poor linear growth during childhood with short final height. Thus, we aimed to assess serum growth hormone (GH), insulin like growth factor-1 (IGF-1) and insulin like growth factor binding protein-3 (IGFBP-3) levels among CP patients and their relation to each of gross motor function and degree of spasticity. Fifty CP children and adolescents were studied in comparison to 50 healthy age-, sex- and pubertal stage-matched children and adolescents. All subjects were subjected to clinical evaluation, Intelligence Quotient (IQ) assessment and measurement of serum GH, IGF-1 and IGFBP-3. All auxological and hormonal parameters were significantly lower among cases. Fifty two% of cases were GH-deficient and 62% had reduced IGF-land IGFBP-3 levels. Gross Motor Function Measure- 88 (GMFM-88) score correlated negatively with each of basal (r = -0.71, p = 0.02) and peak stimulated GH (r =-0.88, p = <0.001); IGF-1 (r = -0.64, p = 0.04) and IGFBP-3 (r = -0.69, p = 0.031). There were significant negative correlations between the degree of spasticity assessed by Modified Ashworth Scale and each of basal (r = -0.61, p = 0.032) and peak stimulated GH (r = -0.78, p = 0.01); IGF-1 (r = -0.65, p = 0.041) and IGFBP-3 (r = -0.62, p = 0.035). Growth Hormone Deficiency (GHD) is prevalent in children with CP and could be one of the causes of their short stature.  相似文献   
79.

Seeking for safe and cheap alternatives to provide the nutrient requirements of crops remains the most significant alternative for obtaining healthy and economical products. Thus, the present study aimed to assess the efficiency of aqueous water hyacinth shoot extract as a source of nutrients to feed tomato plants. Therefore, the effects of three fertilization treatments (without foliar spraying, commercial synthetic solution and natural solution of water hyacinth shoot extract) on the nutritional status and biomass yield of tomato were investigated. The experiment was designed in a randomized complete block design with three replicates. At different growth stages, several macro- and micronutrients, in addition to the final yield at harvest, were estimated. The results showed that at all growth stages of tomato (vegetative, flowering, fruiting and maturity), the natural solution of water hyacinth caused the maximum increases in phosphorus, iron, zinc, manganese, and selenium. However, the differences between the natural solution of water hyacinth and synthetic solution in nitrogen and potassium at the vegetative stage, phosphorus at the flowering and the fruiting stages, and manganese and selenium at the maturity stage were not significant. The increases in fresh and dry weights and fruit yield of tomato plants owing to the natural solution of water hyacinth application were 37.5, 56.8 and 72.2%, respectively, over the control. Natural organic solution of water hyacinth application increased the net return of tomato cultivation by approximately 1.84 and 1.63 times compared with the conventional practice (control) and synthetic chemical solution, respectively. It could be concluded that exploiting the natural organic solution of water hyacinth achieves several profits in agriculture via fertilization programs by enhancing the income of tomato farmers. Accordingly, it is recommended to benefit from the wastes of water hyacinth plants that are annually removed from the Nile River and other waterways.

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80.
Place cells in hippocampal area CA1 may receive positional information from the intrahippocampal associative network in area CA3 or directly from the entorhinal cortex. To determine whether direct entorhinal connections support spatial firing and spatial memory, we removed all input from areas CA3 to CA1, thus isolating the CA1 area. Pyramidal cells in the isolated CA1 area developed sharp and stable place fields. Rats with an isolated CA1 area showed normal acquisition of an associative hippocampal-dependent spatial recognition task. Spatial recall was impaired. These results suggest that the hippocampus contains two functionally separable memory circuits: The direct entorhinal-CA1 system is sufficient for recollection-based recognition memory, but recall depends on intact CA3-CA1 connectivity.  相似文献   
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