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21.
Chlorophyll in soybean represents a downgrading factor for the crops. Five Brazilian cultivars were harvested between R(6) and R(8) stage of development (Fehr & Caviness scale) and dried at 25 degrees and 40 degrees C. The effect of maturity stages and two drying conditions after harvest were studied to achieve reduction of moisture and chlorophylls to acceptable levels. When seeds were dried at 25 degrees C, even harvesting at early stages of development such as R(6), the green pigments were almost degraded, and 16 ppm of chlorophyll were found at maximum, accompanied by loss of moisture. Moisture and chlorophyll declines as seed matures, but at intermediary stages (R(6)-R(7)), chlorophyll degrades first, so the rate of moisture loss should not be used to predict chlorophyll contents. At 40 degrees C, complete degradation of chlorophyll pigments is only achieved when seeds are swathed from R(7) stage up, otherwise the seed quality could be compromised. Slow drying allows almost complete removal of green pigments, even when seeds are swathed a few days before the physiological maturity stage.  相似文献   
22.
A method for allocating allowable ranges of total nitrogen (TN) load to nonpoint (diffuse pollution) sources in a watershed has been developed by adopting the two-phase grey fuzzy optimization approach. Competing goals of water quality management authorities and TN load dischargers at nonpoint sources such as paddy field, upland crop field, and residential area are described with linear imprecise membership functions including interval numbers. TN load discharged from each cell of the nonpoint sources is assumed to be transported along with surface, subsurface, and river flow under the conventional first-order kinetic removal with respect to distance. The travel length of the load is estimated with a digital elevation model in a geographic information system (GIS). Uncertainty of river discharge and self-purification coefficients appearing in the TN transport model is also expressed with interval numbers. The GIS-aided grey fuzzy optimization model developed here is applied to the Seimei River watershed, Japan. By solving the optimization model, the allowable load represented by an interval number at each cell is procured, which would be a scientific base for effluent control regarding nonpoint sources in the area.  相似文献   
23.
The current tuberculosis treatment regimen is long and complex, and its failure leads to relapse and emergence of drug resistance. One of the major reasons underlying the extended chemotherapeutic regimen is the ability of Mycobacterium tuberculosis to attain a dormant state. Therefore, the identification of new lead compounds with chemical structures different from those of conventional anti-tuberculosis drugs is essential. The compound 3-(phenethylamino)demethyl(oxy)aaptamine (PDOA, 1), isolated from marine sponge of Aaptos sp., is known as an anti-dormant mycobacterial substance, and has been reported to be effective against the drug resistant strains of M. tuberculosis. However, its target protein still remains unclear. This study aims to clarify the structure–activity relationship of 1 using 15 synthetic analogues, in order to prepare a probe molecule for detecting the target protein of 1. We succeeded in creating the compound 15 with a photoaffinity group that retained antimicrobial activity, which proved to be a suitable probe molecule for identifying the target protein of 1.  相似文献   
24.
Although mast cells contribute to host protective immunity against bacterial infections, the exact mechanism of their recruitment at the affected site has been unclear. Recently, we have reported that both mouse and human mast cells are capable of producing matrix metalloproteinase (MMP)-9, a matrix-degrading enzyme necessary for leukocyte transmigration. Here, we demonstrated that bacterial lipopolysaccharide (LPS) enhanced MMP-9 production of mouse bone marrow derived-cultured mast cells. This action of LPS was partially suppressed by the pretreatment of cultured mast cells with a protein kinase C (PKC) inhibitor, indicating the possible involvement of PKC signaling pathways in the production of MMP-9 by LPS. Thus, these suggest the upregulation of mast cell MMP-9 by bacterial components, thereby resulting in their migration at the affected site.  相似文献   
25.
The present studies were undertaken to characterise oxidative metabolism with diverse substrates in hepatic mitochondria of acidotic chicks. Metabolic acidosis was experimentally induced by replacement of drinking water with ammonium chloride solution (15 g/l) for 5 d. State 3 oxidation rates in liver mitochondria were significantly reduced in acidotic chicks only for pyruvate and glutamate as substrates requiring complex I, III and IV of the electron transport chain, while they were not changed for either succinate-requiring complexes II, III and IV, ascorbate+TMPD-requiring complex IV, or alpha-ketoglutarate requiring complexes I, III and IV. It can be concluded that the impairment of oxidation rate was substrate-specific in liver mitochondria of acidotic animals and not associated with functional damage of the respiratory chain in mitochondria. Possible reasons for the reductions in oxidation rate with pyruvate and glutamate are discussed.  相似文献   
26.
27.
The goal of the current study was to compare the efficiency of gas exchange and platelet conservation of a new extracapillary blood flow oxygenator versus an endocapillary blood flow oxygenator during open heart surgery with extracorporeal circulation in dogs. Dilation and remodeling of the right ventricular outflow tract of dogs was performed using a patch graft technique to simulate pulmonary stenosis. Sequential pre- and post-operative blood analysis revealed that gas exchange efficiency and platelet conservation was significantly greater with the extracapillary blood flow oxygenator than with the endocapillary blood flow oxygenator. However, the priming volume of the extracapillary blood flow oxygenator was significantly greater, leading to hemodilution. We conclude that while the extracapillary blood flow oxygenator provided benefits in terms of gas exchange and platelet conservation, development of a smaller extracapillary blood flow type oxygenator to reduce hemodilution effects would be beneficial.  相似文献   
28.
Platelet life span was measured in dogs with experimentally-induced mitral regurgitation (MR) by using an in vitro whole-blood biotinylation technique to evaluate the effects of shear stress induced by MR. Mitral regurgitation was created in healthy dogs by ablation of the mitral valve chordae tendineae. Mitral regurgitation was identified by auscultation and postoperative color Doppler echocardiography. Platelets were biotinylated. and derivatized blood was reinfused into the dogs. Biotinylated platelet disappearance was measured over time to determine platelet life span. Pre- and postablation platelet life span was compared in each dog. Platelet life span was shorter in dogs with experimentally induced MR. Shear stress from MR was postulated to shorten platelet life span. Alternations in platelet function and life span may contribute to the progression of cardiovascular disease in dogs with MR. Further studies are required to determine if platelet dysfunction is related to disease progression in these patients.  相似文献   
29.
The clinical complications occurring after 111 dogs had undergone arterial punctures were reviewed in relation to the dogs' breed, bodyweight, age, sex and underlying diseases. Seven of the dogs had moderate to extensive ecchymoses, which were significantly more common in dogs under 3.5 kg in bodyweight and in dogs with disorders of the cardiovascular system.  相似文献   
30.
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