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1.
A study on the rice–wheat cropping system was conducted at Bidhan Chandra Krishi Viswavidyalaya, West Bengal, India, to assess the effects of long-term manuring and fertilization on transformation of the inorganic phosphorus (P) fraction in soil after 22 years of the crop cycle. Soil samples were collected after Kharif from seven treated plots having different types of organic amendments like farm yard manure, paddy straw and green manuring with 50% substitution of nitrogen levels in rice crop only. The result showed that the yield trend of rice was maintained due to the buildup of P from various organic inputs. Although cultivation for 22 years without adding any fertilizer caused a significant decrease in almost all the forms of P viz. avail-P, saloid P, iron phosphorus fraction (Fe–P), aluminum phosphorus fraction (Al–P), calcium phosphorus fraction (Ca–P) and total P in control. Partial substitution of inorganic fertilizer N (50%) with organics, however, caused a significant increase in almost all the P fractions in soil over the control. The relative abundance of all the fractions of inorganic P irrespective of treatments was as follows: Fe–P > reductant soluble P fraction > occluded P > Al–P > Ca–P > saloid P. Saloid and Fe–P were the dominating fractions responsible for 92% variation of available P and total P levels, respectively.  相似文献   
2.
This report deals with a case of cutaneous toxoplasmosis in a 2 year-old female Angora cat. Cutaneous lesions were characterized by prescapular ulcers and hyperemic nodules in the skin of the inguinal and dorsosacral regions. A skin biopsy sample was collected from the lesioned area and processed for histopathologic examination and immunoperoxidase test using Toxoplasma gondii and Neospora caninum specific antibodies. Toxoplasma gondii immunopositive reactions were detected in keratinocytes and dermal macrophages while no immunoreactivity was detected for N. caninum. The case of cutaneous toxoplasmosis was further confirmed by PCR analysis using T. gondii B1 gene-specific primers. In conclusion, we report the first case of cutaneous toxoplasmosis in Angora cats.  相似文献   
3.
Marine invertebrates including sponges, soft coral, tunicates, mollusks and bryozoan have proved to be a prolific source of bioactive natural products. Among marine-derived metabolites, terpenoids have provided a vast array of molecular architectures. These isoprenoid-derived metabolites also exhibit highly specialized biological activities ranging from nerve regeneration to blood-sugar regulation. As a result, intense research activity has been devoted to characterizing invertebrate terpenes from both a chemical and biological standpoint. This review focuses on the chemistry and biology of terpene metabolites isolated from the Red Sea ecosystem, a unique marine biome with one of the highest levels of biodiversity and specifically rich in invertebrate species.  相似文献   
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Wave propagation techniques based on ultrasound for timber grading are influenced by the moisture content (MC) of wood. The ultrasound velocities at an equilibrium MC (V12) and above saturation point (Vsat) were used to calculate moisture-related adjustment factors (kH). Tests were conducted using plantation hardwoods (Corymbia citriodora, Eucalyptus grandis and Eucalyptus pellita) grown in Brazil. Below the fiber saturation point (FSP), kH values were between 0.66% and 0.83%, which concurred with intervals proposed in existing literature for softwoods. However, the kH inferred from the velocities obtained at MCs above the FSP increased (from 10% to 30%) with increasing density. The sound velocity under saturated conditions (Vsat) obtained by adjustment equations was 2–9% lower than the actual Vsat obtained from the tests. The obtained adjustment factors may be useful for the standardization of nondestructive timber grading based on ultrasound propagation.  相似文献   
7.
The soft coral genus Sarcophyton contains the enzymatic machinery to synthesize a multitude of cembrene-type diterpenes. Herein, highly oxygenated cembrenoids, sarcoconvolutum A–E (1–5) were purified and characterized from an ethyl acetate extract of the red sea soft coral, Sarcophyton convolutum. Compounds were assemblies according to spectroscopic methods including FTIR, 1D- and 2D-NMR as well as HRMS. Metabolite cytotoxicity was tested against lung adenocarcinoma, cervical cancer, and oral-cavity carcinoma (A549, HeLa and HSC-2, respectively). The most cytotoxic compound, (4) was observed to be active against cell lines A549 and HSC-2 with IC50 values of 49.70 and 53.17 μM, respectively.  相似文献   
8.
A chemical investigation of an ethyl acetate extract of the Red Sea soft coral Sarcophyton glaucum has led to the isolation of two peroxide diterpenes, 11(S) hydroperoxylsarcoph-12(20)-ene (1), and 12(S)-hydroperoxylsarcoph-10-ene (2), as well as 8-epi-sarcophinone (3). In addition to these three new compounds, two known structures were identified including: ent-sarcophine (4) and sarcophine (5). Structures were elucidated by spectroscopic analysis, with the relative configuration of 1 and 2 confirmed by X-ray diffraction. Isolated compounds were found to be inhibitors of cytochrome P450 1A activity as well as inducers of glutathione S-transferases (GST), quinone reductase (QR), and epoxide hydrolase (mEH) establishing chemo-preventive and tumor anti-initiating activity for these characterized metabolites.  相似文献   
9.
In this study, 481 cattle belonging to 77 farms from nine localities in Trakya district in the Marmara region of Turkey were blood sampled and serologically tested for enzootic bovine leukosis (EBL). Antibodies to bovine leukosis virus (BLV) were detected in 51 cattle sera (11%) belonging to nine farms in five localities. Cattle tested were mostly female Holstein or Brown Swiss of ages ranging between 18 months and 10 years. Analysis of the relationships between age, breed or sex and seropositivity to EBL in seropositive herds indicated no significant associations (p>0.05). The relationship between seropositivity and haematological changes was also studied, and seropositive cattle had higher lymphocyte percentage and lower neutrophil percentage than seronegative cattle (p<0.001).  相似文献   
10.
The quantification of phosphorus(P) in bulk soil and P distribution in different size fractions of water-stable aggregates(WSAs)are important for assessing potential P loss through runoff. We evaluated available and total P distribution within WSAs of a sitty clay to clay soil in a long-term fertility experiment of a rice-wheat cropping system in India. Surface soil samples were collected from seven plots amended with NPK fertilizers in combination with or without organic amendments, farmyard manure(FYM), green manure(GM), and paddy straw(PS). The plot with no NPK fertilizers or organic amendments was set as a control. The soil samples were separated by wet sieving into four soil aggregate size fractions: large macroaggregates( 2.0 mm), small macroaggregates(0.25–2.0 mm), fine microaggregates(0.05–0.25 mm), and a silt + clay-sized fraction( 0.05 mm). Structural indices were higher in the soil receiving organic amendments than in the soil receiving inorganic fertilizer alone. Organically amended soil had a higher proportion of stable macroaggregates than the control and the soil receiving inorganic fertilizer alone, which were rich in microaggregates. Total and available P contents within WSAs were inversely related to the aggregate size, irrespective of treatment. The distribution of available and total P in the soil aggregate size fraction was as follows: silt + clay-size fraction small macroaggregates fine microaggregates large macroaggregates. Within a size class, aggregate-associated available and total P contents in the organically amended soil were in the following order: FYM PS ≥ GM. The available P content of the microaggregates( 0.25 mm) was 8-to 10-times higher than that of the macroaggregates( 0.25 mm), and the total P content of the microaggregates was 4-to 5-times higher than that of the macroaggregates. Cultivation without organic amendments resulted in more microaggregates that could be checked by the application of organic amendments such as FYM and GM, which increased the proportion of water-stable macroaggregates by consolidating microaggregates into macroaggregates.  相似文献   
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