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91.
92.
The population dynamics of Heterodera glycines as influenced by alachlor, fenamiphos, and ethoprop alone and in herbicide-nematicide combinations were studied in the field. Numbers of H. glycines juveniles and eggs were higher at midseason and harvest where nematicides were applied. Fenamiphos alone or in combination with alachlor provided better control of H. glycines and greater seed yields than treatments with ethoprop. Numbers of H. glycines eggs at harvest in 1980 were positively correlated with numbers of juveniles at planting in 1981 and negatively related to seed yield in 1981.  相似文献   
93.
Series of nanoporous carbons are prepared from sunflower seed shell (SSS) by two different strategies and used as electrode material for electrochemical double-layer capacitor (EDLC). The surface area and pore-structure of the nanoporous carbons are characterized intensively using N2 adsorption technique. The results show that the pore-structure of the carbons is closely related to activation temperature and dosage of KOH. Electrochemical measurements show that the carbons made by impregnation-activation process have better capacitive behavior and higher capacitance retention ratio at high drain current than the carbons made by carbonization-activation process, which is due to that there are abundant macroscopic pores and less interior micropore surface in the texture of the former. More importantly, the capacitive performances of these carbons are much better than ordered mesoporous carbons and commercial wood-based active carbon, thus highlighting the success of preparing high performance electrode material for EDLC from SSS.  相似文献   
94.
Suspension cultures of ‘Chang liver’ cells were synchronized by preincubation in a glutamine-deficient medium or by thymidine blockade. Specific arginase activity varied in the synchronized cultures, being high when the number of S-phase cells was maximal. A relationship between high arginase activity and a high percentage of (S+G2) cells was also found when unsynchronized cells were separated by velocity sedimentation. The increase in arginase activity near the G1/S border was totally inhibited in the presence of cycloheximide. The rate of decrease in activity after addition of the drug indicated that the variations in the rate of synthesis of the enzyme, while the rate of degradation was more or less constant, corresponding to 4–6% per h. The role of arginase in cells lacking a urea cycle and the regulation of arginase activity in ‘Chang liver’ cells is discussed.  相似文献   
95.
Plots of fresh pulverized fuel ash (PFA, an industrial waste) were inoculated with soils from existing PFA sites and fertilizers in a factorial design, then left unmanaged for 12 years during which time the floral development and soil chemistry were monitored annually. For the first 3 years, the site supported a sparse mix of chenopods (including the scarce Chenopodium glaucum ) and halophytes. As salinity declined, ruderals, legumes, and grasses plus the fire-site moss Funaria hygrometrica colonized, followed by Festuca arundinacea grassland (NVC community MG12) and Hippophae rhamnoides scrub. Dactylorhiza incarnata (orchidacea) appeared after 7 years, but only in plots that had received soil from existing orchid colonies. Four years later, a larger second generation of Dactylorhiza appeared, but only in the central zone of the site where vegetation was thinnest. By year 12, the site was dominated by coarse grasses and scrub, with early successional species persisting only in the sparsely vegetated center, where nitrate levels were lowest. This edge effect is interpreted as centripetal encroachment, a process of potentially wider concern for the conservation of low-fertility habitat patches. Overall, seed bank inoculation seems to have introduced few but desirable species ( D. incarnata , Pyrola rotundifolia , some halophytes, and annuals), whereas initial application of organic fertilizer had long-lasting (≥10 years) effects on cover and soil composition.  相似文献   
96.
《Endocrine practice》2021,27(12):1225-1231
ObjectiveBone health in older individuals with HIV infection has not been well studied. This study aimed to compare bone mineral density (BMD), trabecular bone score (TBS), and bone markers between HIV-infected men and age- and body mass index (BMI)-matched HIV-uninfected men aged ≥60 years. We investigated the associations of risk factors related to fracture with BMD, TBS, and bone markers in HIV-infected men.MethodsThis cross-sectional study included 45 HIV-infected men receiving antiretroviral therapy and 42 HIV-uninfected men. Medical history, BMD and TBS measurements, and laboratory tests related to bone health were assessed in all the participants. HIV-related factors known to be associated with bone loss were assessed in the HIV-infected men.ResultsThe mean BMD, TBS, and osteopenia or osteoporosis prevalence were similar among the cases and controls. The HIV-infected men had significantly higher mean N-terminal propeptide of type 1 procollagen and C-terminal cross-linking telopeptide of type I collagen levels. Stepwise multiple linear regression analysis demonstrated that low BMI (lumbar spine, P = .015; femoral neck, P = .018; and total hip, P = .005), high C-terminal cross-linking telopeptide of type I collagen concentration (total hip, P = .042; and TBS, P = .010), and low vitamin D supplementation (TBS, P = .035) were independently associated with low BMD and TBS.ConclusionIn older HIV-infected men with a low fracture risk, the mean BMD and TBS were similar to those of the age- and BMI-matched controls. The mean bone marker levels were higher in the HIV group. Traditional risk factors for fracture, including low BMI, high C-terminal cross-linking telopeptide of type I collagen level, and low vitamin D supplementation, were significant predictors of low BMD and TBS.  相似文献   
97.
The copper complex of indomethacin (1-(p-chlorobenzoyl)-5-methoxy-2-methyl-indole acetate), a common anti-inflammatory drug, was prepared and characterized. Crystal structure determination revealed the dimeric form of the 1:2 complex, namely Cu2(indomethacin)4 · L2, in the unit cell. Suprisingly, the copper-copper distance (263 pm) was very close to metallic copper (256 pm). The two coordination sites in the copper-copper axis can be readily replaced by superoxide. An intriguing similarity to Cu2(acetate)4 was seen.Due to the lipophilic nature of the indomethacin ligand, this copper complex reacted with superoxide in aprotic solvents. The superoxide dismutating activity was successfully demonstrated in Me2SO/water and acetonitrile/water mixtures using the nitro-blue tetrazolium assay and pulse radiolysis. The second-order rate constant of 6 · 109 M?1 · s?1 in strictly aqueous systems dropped only slightly to 1.1 · 109 M?1 · s?1 when aprotic solvents were used. This is the fastest rate constant ever observed for a copper-dependent dismutation of superoxide. The KO2-induced lipid peroxidation in both erythrocytes and liver microsomes was suppressed by 70% in the presence of 1 · 10?10 mol · ml?1 of Cu2(indomethacin)4. The inhibitory action dropped to 25% when Cu2Zn2superoxide dismutase was employed. The formation of copper · indomethacin in rat serum after administration of indomethacin was shown in vitro and in vivo.  相似文献   
98.
Intestinal cholesterol absorption is specifically inhibited by the 2-azetidinone cholesterol absorption inhibitor ezetimibe. Photoreactive ezetimibe analogues specifically label a 145-kDa protein in the brush border membrane of enterocytes from rabbit small intestine identified as aminopeptidase N (CD13). In zebrafish and mouse small intestinal cytosol, a heterocomplex of Mr 52 kDa between annexin II and caveolin 1 was suggested as a target of ezetimibe. In contrast, in the cytosol and brush border membrane vesicles (BBMV) from rabbit small intestine of control animals or rabbits treated with the nonabsorbable cholesterol absorption inhibitor AVE 5530, both annexin II and caveolin 1 were exclusively present as monomers without any heterocomplex formation. Upon immunoprecipitation with annexin II a 52-kDa band was observed after immunostaining with annexin II antibodies, whereas no staining of a 52-kDa band occurred with anti-caveolin 1 antibodies. Vice versa, a 52-kDa band obtained by immunoprecipitation with caveolin 1 antibodies did not stain with annexin II-antibodies. The intensity of the 52-kDa band was dependent on the amount of antibody and was also observed with anti-actin or anti-APN antibodies suggesting that the 52-kDa band is a biochemical artefact. After incubation of cytosol or BBMV with radioactively labelled ezetimibe analogues, no significant amounts of the ezetimibe analogues could be detected in the immunoprecipitate with caveolin-1 or annexin II antibodies. Photoaffinity labelling of rabbit small intestinal BBMV with ezetimibe analogues did not result in labelling of proteins being immunoreactive with annexin II, caveolin 1 or a 52-kDa heterocomplex. These findings indicate that the rabbit small intestine does not contain an annexin II/caveolin 1 heterocomplex as a target for ezetimibe.  相似文献   
99.
100.
One model for the timing of cytokinesis is based on findings that p34(cdc2) can phosphorylate myosin regulatory light chain (LC20) on inhibitory sites (serines 1 and 2) in vitro (Satterwhite, L.L., M.H. Lohka, K.L. Wilson, T.Y. Scherson, L.J. Cisek, J.L. Corden, and T.D. Pollard. 1992. J. Cell Biol. 118:595-605), and this inhibition is proposed to delay cytokinesis until p34(cdc2) activity falls at anaphase. We have characterized previously several kinase activities associated with the isolated cortical cytoskeleton of dividing sea urchin embryos (Walker, G.R., C.B. Shuster, and D.R. Burgess. 1997. J. Cell Sci. 110:1373-1386). Among these kinases and substrates is p34(cdc2) and LC20. In comparison with whole cell activity, cortical H1 kinase activity is delayed, with maximum levels in cortices prepared from late anaphase/telophase embryos. To determine whether cortical-associated p34(cdc2) influences cortical myosin II activity during cytokinesis, we labeled eggs in vivo with [(32)P]orthophosphate, prepared cortices, and mapped LC20 phosphorylation through the first cell division. We found no evidence of serine 1,2 phosphorylation at any time during mitosis on LC20 from cortically associated myosin. Instead, we observed a sharp rise in serine 19 phosphorylation during anaphase and telophase, consistent with an activating phosphorylation by myosin light chain kinase. However, serine 1,2 phosphorylation was detected on light chains from detergent-soluble myosin II. Furthermore, cells arrested in mitosis by microinjection of nondegradable cyclin B could be induced to form cleavage furrows if the spindle poles were physically placed in close proximity to the cortex. These results suggest that factors independent of myosin II inactivation, such as the delivery of the cleavage stimulus to the cortex, determine the timing of cytokinesis.  相似文献   
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