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排序方式: 共有264条查询结果,搜索用时 15 毫秒
101.
102.
This work describes integrated nutrient management for cultivation of Allium hookeri by using phosphate solubilizing bacteria (PSB) applied in rhizosphere, along with tricalcium phosphate (TCP). Arthrobacter luteolus S4C7, Enterobacter asburiae S5C7, Klebsiella pneumoniae S4C9, S4C10 and S6C1, and K. quasipneumoniae S6C2, were isolated from rhizosphere of Allium hookeri Thwaites, and were found to release substantial amount of soluble phosphate (124.8–266.4?μg/mL) from TCP in vitro conditions. These isolates were experimented for plant growth promoting attributes, including IAA, siderophore, and nitrogen-fixation. Treatment with PSB resulted in enhanced growth of A. hookeri Th., which was even better with TCP amendment with PSB. K.quasipneumoniae S6C2 resulted in 39.1% and 533.3% increase (p?≤?0.05) of root length and weight respectively. The treatment with these isolates, in TCP amended soil also resulted in 200–250% increase in available P in soil, which was maximum for K. quasipneumoniae (1.866?mg/g). 相似文献
103.
Heme metabolism in promastigotes of Leishmania donovani 总被引:3,自引:0,他引:3
Srivastava Pratima Sharma Guru Dutt Kamboj Kamal K. Rastogi Anil K. Pandey Vikas C. 《Molecular and cellular biochemistry》1997,171(1-2):65-68
Promastigotes of Leishmania donovani (Dd-8 strain) showed presence of important key enzymes of heme synthesizing (d-aminolevulinic acid synthase and ferrochelatase) and degrading (heme oxygenase and biliverdin reductase) systems, classical leishmanicidal drugs viz allopurinol, amphotericin B, pentamidine and CDRI compound 93/202 inhibited the heme oxygenase activity of the parasite, whereas, -aminolevulinic acid synthase activity practically remained unaffected. The Km, Vmax ad pH values of heme oxygenase of promastigotes were found to be 1666 M hemin, 625 nmol of bilirubin formed h-1 mg protein-1 and 7.5 respectively. The findings suggest the presence and importance of heme metabolism in the de novo synthesis of different hemoproteins of the Leishmania parasite as well as the detoxification and its defence against biological insults. 相似文献
104.
R M Garruto C C Plato R Yanagihara K Fox J Dutt D C Gajdusek J Tobin 《American journal of physical anthropology》1989,80(1):107-113
Bone mass, as assessed by measurements of total subperiosteal diameter and medullary width of the second metacarpal bone on hand-wrist radiographs, was evaluated for 31 Guamanian patients (15 males, 16 females) with amyotrophic lateral sclerosis (ALS), 67 patients (39 males, 28 females) with parkinsonism-dementia (PD), and 66 (34 males, 32 females) nonaffected Guamanian controls. Comparisons between the two disease groups and between each disease group and the nonaffected controls were made taking into account the sex, age, and disability status of each participant. At all ages, ALS patients of both sexes had significantly lower percent cortical areas (PCA) than did nonaffected controls. The ALS males also had significantly lower PCA than PD males, although no significant differences were observed between female ALS and PD patients. The PD patients of either sex had a lower PCA when compared to controls, but the differences were not statistically significant. The observed differences in PCA were due solely to increased medullary width, suggesting that the diminished cortical bone thickness resulted from greater bone resorption rather than differential bone growth. Longitudinal studies support the cross-sectional findings of accelerated bone loss among ALS patients. It is not possible to determine from the present data whether the observed differences in PCA of the second metacarpal of the ALS patients are due to atrophy of the first interosseous muscle, to a generalized resorption process inherently associated with the development and progression of ALS, or to factors not accounted for by the present analysis. 相似文献
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108.
Brianne M. Bettcher Christa L. Watson Christine M. Walsh Iryna V. Lobach John Neuhaus Joshua W. Miller Ralph Green Nihar Patel Shubir Dutt Edgar Busovaca Howard J. Rosen Kristine Yaffe Bruce L. Miller Joel H. Kramer 《PloS one》2014,9(9)
The contribution of inflammation to deleterious aging outcomes is increasingly recognized; however, little is known about the complex relationship between interleukin-6 (IL-6) and brain structure, or how this association might change with increasing age. We examined the association between IL-6, white matter integrity, and cognition in 151 community dwelling older adults, and tested whether age moderated these associations. Blood levels of IL-6 and vascular risk (e.g., homocysteine), as well as health history information, were collected. Processing speed assessments were administered to assess cognitive functioning, and we employed tract-based spatial statistics to examine whole brain white matter and regions of interest. Given the association between inflammation, vascular risk, and corpus callosum (CC) integrity, fractional anisotropy (FA) of the genu, body, and splenium represented our primary dependent variables. Whole brain analysis revealed an inverse association between IL-6 and CC fractional anisotropy. Subsequent ROI linear regression and ridge regression analyses indicated that the magnitude of this effect increased with age; thus, older individuals with higher IL-6 levels displayed lower white matter integrity. Finally, higher IL-6 levels were related to worse processing speed; this association was moderated by age, and was not fully accounted for by CC volume. This study highlights that at older ages, the association between higher IL-6 levels and lower white matter integrity is more pronounced; furthermore, it underscores the important, albeit burgeoning role of inflammatory processes in cognitive aging trajectories. 相似文献
109.
V K Vinayak N Singla P Dutt D Mahajan 《Japanese journal of medical science & biology》1991,44(3):109-121
A 66-kDa major plasma membrane-associated molecule of promastigotes of Leishmania donovani (UR6) was purified by affinity chromatography. The immunoreactivity of the 66-kDa molecule was lost upon exposure to heat or treatment with trypsin. The metaperiodate oxidation significantly reduced its immunoreactivity. The 66-kDa molecule is, therefore, glycoprotein in nature. With a fluorescent probe, the 66-kDa molecule was found to be located on the tip of flagellum and on the kinetoplast. The exposure of promastigotes of L. donovani to monospecific anti-66-kDa antibodies significantly reduced the percentage of macrophages with attached promastigotes in the cultured cell line (J774G8). The data suggested that promastigotes of L. donovani utilize the 66-kDa molecule in recognizing and as ligand for binding to macrophages. 相似文献
110.
Proteomic analysis 总被引:10,自引:0,他引:10
The field of proteomics is becoming increasingly important as genome sequences are being completed and annotated. Recent advances in proteomics include experimental and mathematical proofs of the need to complement microarray analysis with protein analysis, improved sensitivity for mass spectrometric analysis of separated proteins, better informatic tools for gel analysis and protein spot annotation, first steps towards automated experimental procedures, and new technology for quantitation of protein changes. 相似文献