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661.
Rafiq Ahmad 《BioControl》1970,15(3):233-235
During the course of studies on scale insects and their natural enemies in West Pakistan, this species was found to be predaceous onAonidiella orientalis (Newst.),Chrysomphalus ficus (Ashm.),Parlatoria blanchardii (Targ.),P. crypta Mck. andTecaspis sp. Its population was extremely low except at Mirpur Khas (Sub-coastal area) where it was abundant onA. orientalis attackingMusa sapientum. It proved to be new to science and is described below.  相似文献   
662.
663.
The purpose of this work was to determine solution- and solid-phase changes associated with the oxidative leaching of arsenopyrite (FeAsS) by Thiobacillus ferrooxidans and a moderately thermoacidophilic mixed culture. Jarosite [KFe3(SO4)2(OH)6], elemental sulfur (S0), and amorphous ferric arsenate were detected by X-ray diffraction as solid-phase products. The oxidation was not a strongly acid-producing reaction and was accompanied by a relatively low redox level. The X-ray diffraction lines of jarosite increased considerably when ferrous sulfate was used as an additional substrate for T. ferroxidans. A moderately thermoacidophilic mixed culture oxidized arsenopyrite faster at 45°C than did T. ferroxidans at 22°C, and the oxidation was accompanied by a nearly stoichiometric release of Fe and As. The redox potential was initially low but subsequently increased during arsenopyrite oxidation by the thermoacidophiles. Jarosite, S0, and amorphous ferric arsenate were also formed under these conditions.  相似文献   
664.
Our laboratory is involved in investigating the role of T-cell receptor (Tcr) in collagen-induced arthritis (CIA). During these studies we found AU/ssJ (H-2 q ) mice to be resistant to CIA like SWR (H-2 q ), as compared with other H-2 q strains with wild-type Tcr like DBA/1 and B 10. Q. Upon screening with monoclonal antibodies F23.1 and KJ23a, AU/ssJ was found to be F23.1 negative (V 8 Tcr negative) and KJ23a positive (V 17a Tcr positive). Southern blot analysis on liver DNA using specific Tcr-V probes confirmed the deletion of V 8 gene family and also showed that AU/ssJ mice have deletions of V 9, V 13, V 12, and V 11 genes of Tcr. Further, these mice show a restriction fragment length polymorphism pattern with V 10, V 6, and V 17 probes similar to SWR mice as compared with 1310 mice. Since SWR and AU/ssJ are from different backgrounds, these studies indicate that specific variable region chain genes of Tcr are crucial for susceptibility to CIA in mice. Furthermore, these studies identify an additional inbred strain which has also deleted 50% of its Tcr-V genes.  相似文献   
665.
The rapid modulation of ligand-binding affinity ("activation") is a central property of the integrin family of cell adhesion receptors. The small GTP-binding protein Ras and its downstream effector kinase Raf-1 suppress integrin activation. In this study we explored the relationship between Ras and the closely related small GTP-binding protein R-Ras in modulating the integrin affinity state. We found that R-Ras does not seem to be a direct activator of integrins in Chinese hamster ovary cells. However, we observed that GTP-bound R-Ras strongly antagonizes the Ras/Raf-initiated integrin suppression pathway. Furthermore, this reversal of the Ras/Raf suppressor pathway does not seem to be via a competition between Ras and R-Ras for common downstream effectors or via an inhibition of Ras/Raf-induced MAP kinase activation. Thus, R-Ras and Ras may act in concert to regulate integrin affinity via the activation of distinct downstream effectors.  相似文献   
666.
667.
Journal of Plant Growth Regulation - Salinity stress is the major abiotic stress that affects crop production and productivity as it has a multifarious negative effect on the growth and development...  相似文献   
668.
Journal of Plant Growth Regulation - Endophytic microbes promote plant growth through various biochemical mechanisms and assist plants in resuming their morpho-physiological traits under abiotic...  相似文献   
669.

Nitrogen (N), the building block of plant proteins and enzymes, is an essential macronutrient for plant functions. A field experiment was conducted to investigate the impact of different N application rates (28, 57, 85, 114, 142, 171, and 200 kg ha−1) on the performance of spring wheat (cv. Ujala-2016) during the 2017–2018 and 2018–2019 growing seasons. A control without N application was kept for comparison. Two years mean data showed optimum seed yield (5,461.3 kg ha−1) for N-application at 142 kg ha−1 whereas application of lower and higher rates of N did not result in significant and economically higher seed yield. A higher seed yield was obtained in the 2017–2018 (5,595 kg ha−1) than in the 2018–2019 (5,328 kg ha−1) growing seasons under an N application of 142 kg ha−1. It was attributed to the greater number of growing degree days in the first (1,942.35°C days) than in the second year (1,813.75°C). Higher rates of N (171 and 200 kg ha−1) than 142 kg ha−1 produced more number of tillers (i.e., 948,300 and 666,650 ha−1, respectively). However, this increase did not contribute in achieving higher yields. Application of 142, 171, and 200 kg ha−1 resulted in 14.15%, 15.0% and 15.35% grain protein concentrations in comparison to 13.15% with the application of 114 kg ha−1. It is concluded that the application of N at 142 kg ha−1 could be beneficial for attaining higher grain yields and protein concentrations of wheat cultivar Ujala-2016.

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670.
Abstract The major extracellular proteases from the nematophagous fungus Verticillium chlamydosporium and the entomophagous fungus Metarhizium anisopliae , VCP1 and Pr1, respectively, are closely related both functionally and serologically. Antibodies raised against either enzyme cross-reacted with both antigens, suggesting that they have common epitopes. The VCP1 and Prl antisera labelled bovine pancreatic elastase and proteinase K, respectively. Neither antiserum reacted with commercial chymotrypsin. An antiserum to a serine protease from the closely related V. suchlasporium also cross-reacted with VCP1 and Prl. In contrast, a polyclonal antibody to an isoform of Pr1 exclusive to M. anisopliae isolate ME1 failed to recognize Prl from M. anisopliae V245 or VCP1. The N-terminal amino acid sequence of VCP1 revealed similarities with subtilisin-like enzymes from other fungi, but the closest match was with Pr1. The pure enzymes, VCP1 and Prl, failed to hydrolyse mono-aminoacyl-naphthylamide substrates but demonstrated dipeptidyl peptidase activity against Gly-Pro-βNA and Leu-Ala-βNA, respectively. These results are discussed in the context of specificity of invertebrate mycopathogens.  相似文献   
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