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91.
92.
The human P1-450 gene (6,311 base pairs), as well as the 5' (1,604 bases) and 3' (113 bases) flanking regions, have been completely sequenced. Four highly homologous boxes (61, 82, 56 and 97 base pairs) between the human and mouse P1-450 genes are found in the "TATA" box promoter region, -226, -338, and -450 upstream from the cap site, respectively. Nine genomic-DNA samples were digested with each of 23 restriction endonucleases and probed with human P1-450 cDNA fragments; restriction fragment length polymorphisms are detected, although it remains to be seen whether such a recombinant DNA test will be useful in determining individuals at increased risk for cigarette smoking-induced cancer and toxicity. We show in this report, however, that human inducible P1-450 mRNA concentrations are very highly correlated (r = 0.98; N = 6) with genetic differences in benzo[a]pyrene metabolism in mitogen-activated lymphocyte cultures.  相似文献   
93.
Biological Trace Element Research - The primary objective of the present study was to assess the level of selenium and toxic trace elements in wheat, rice, maize, and mustard from seleniferous...  相似文献   
94.
Indigenous soybean rhizobial strains were isolated from root nodules sampled from farmers’ fields in Mozambique to determine their identity, distribution and symbiotic relationships. Plant infection assays revealed variable nodulation and symbiotic effectiveness among the 43 bacterial isolates tested. Strains from Ruace generally promoted greater whole-plant growth than the others. 16S rRNA-RFLP analysis of genomic DNA extracted from the rhizobial isolates produced different banding patterns, a clear indication of high bacterial diversity. However, the multilocus sequence analysis (MLSA) data showed alignment of the isolates with B. elkanii species. The 16S rRNA sequences of representative soybean isolates selected from each 16S rRNA-RFLP cluster showed their relatedness to B. elkanii, as well as to other Bradyrhizobium species. But a concatenated phylogeny of two housekeeping genes (glnII and gyrB) identified the soybean nodulating isolates as Bradyrhizobium, with very close relatedness to B. elkanii. The nifH and nodC sequences also showed that the majority of the test soybean isolates were closely related to B. elkanii, albeit the inconsistency with some isolates. Taken together, these findings suggest that the B. elkanii group are the preferred dominant microsymbiont of soybean grown in Mozambican soils. Furthermore, the distribution of soybean rhizobia in the agricultural soils of Mozambique was found to be markedly influenced by soil pH, followed by the concentrations of plant-available P and Mn. This study suggested that the identified isolates TUTMJM5, TUTMIITA5A and TUTLBC2B can be used as inoculants for increased soybean production in Mozambique.  相似文献   
95.
Grain traits are important agronomic attributes with the market value as well as milling yield of bread wheat. In the present study, quantitative trait loci (QTL) regulating grain traits in wheat were identified. Data for grain area size (GAS), grain width (GWid), factor form density (FFD), grain length-width ratio (GLWR), thousand grain weight (TGW), grain perimeter length (GPL) and grain length (GL) were recorded on a recombinant inbred line derived from the cross of NW1014?×?HUW468 at Meerut and Varanasi locations. A linkage map of 55 simple sequence repeat markers for 8 wheat chromosomes was used for QTL analysis by Composite interval mapping. Eighteen QTLs distributed on 8 chromosomes were identified for seven grain traits. Of these, five QTLs for GLWR were found on chromosomes 1A, 6A, 2B, and 7B, three QTLs for GPL were located on chromosomes 4A, 5A and 7B and three QTLs for GAS were mapped on 5D and 7D. Two QTLs were identified on chromosomes 4A and 5A for GL and two QTLs for GWid were identified on chromosomes 7D and 6A. Similarly, two QTLs for FFD were found on chromosomes 1A and 5D. A solitary QTL for TGW was identified on chromosome 2B. For several traits, QTLs were also co-localized on chromosomes 2B, 4A, 5A, 6A, 5D, 7B and 7D. The QTLs detected in the present study may be validated for specific crosses and then used for marker-assisted selection to improve grain quality in bread wheat.  相似文献   
96.
Proteins as a biomolecule have been recognized as a “molecule with manifold biological functions”. The functions not only include the structural, regulatory and transportation processes inside the body but also its capacity as an extremely specific catalyst for various biochemical reactions. Nature has been quite admirably using proteins as biocatalysts which are known as enzymes. Properties like higher reaction rate, good specificity, faster kinetics, production of lesser by‐products and their non‐hazardous nature make enzymes the most suitable targets for a process chemist to exploit. At the same time, limitations like a narrow range of substrates, requirement of coenzymes, lesser stability, smaller shelf‐life, along with difficulties in procuring these enzymes, make this biocatalysis field quite challenging. For exploiting a broad range of applications related to therapeutics, biosensors, biotechnology, nanotechnology etc., de novo designing of proteins is of utmost importance. Enzymes with altered, specific and modified properties might be designed by utilizing the prior knowledge of structure and function of a protein with the help of computational modeling. Various protein engineering techniques like directed evolution, rational designing and immobilization strategies etc. have already been extensively used to address some of the issues. This review aims to update the repertoire of the advancements in the field of protein engineering, which can help in laying some guiding principles about designing, modifying and altering their usage for commercial industrial purposes. This possibility of effective and novel designing of peptides and proteins might further facilitate our understanding about the structure, function and folding patterns along with their inter‐relationships. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
97.

Objectives

To evaluate the contribution of breastfeeding to Rotavirus (RV)-induced antigenemia and/or RNAemia and disease severity in Indian children (<2 yrs age).

Methods

Paired stool and serum samples were collected from (a) hospitalized infants with diarrhea (n = 145) and (b) healthy control infants without diarrhea (n = 28). Stool RV-antigen was screened in both groups by commercial rapid-test and enzyme immunoassay. The disease severity was scored and real-time-PCR was used for viral-load estimation. Serum was evaluated for RV-antigenemia by EIA and RV-RNAemia by RT-PCR. Data was stratified by age-group and breastfeeding status and compared.

Results

Presence of RV-antigenemia and RV-RNAemia was positively related with presence of RV in stool. Disease severity and stool viral-load was significantly associated with RV-antigenemia[(r = 0.74; CI:0.66 to 0.84; P<0.0001,R2 = 0.59) and (r = -0.55; CI:-0.68 to -0.39; P<0.0001,R2 = 0.31) respectively], but not with RV-RNAemia. There was significant reduction in RV-antigenemiarate in the breast-fed group compared to non-breastfed infants, especially in 0–6 month age group (P<0.001). Non-breastfed infants were at risk for RV-antigenemia with severe disease manifestations in form of high Vesikari scores correlating with high fever, more vomiting episodes and dehydration.

Conclusion

RV-antigenemia was common in nonbreastfed children with severe RV-diarrhea and correlated with stool RV-load and disease severity.  相似文献   
98.
Summary The effect of gamma isomer of benzene hexachloride and Telodrin both in absence and presence of ammonium and nitrate nitrogen carriers on shoot and root growth and carboydrate and nitrogen constituents of sugarcane was studied. The pesticides induced shoot emergence and development of tillers and roots. Shoot growth, nitrogen intake and insoluble nitrogen content invariably increased by pesticide application while soluble carbohydrate and soluble nitrogen content of the shoot decreased. Pesticides also increased the water-soluble nitrate content of the soil.The effect of pesticides was not confined to ammonical source of nitrogen rather the pesticides proved equally effective under nitrate source of nitrogen and also in absence of additional nitrogen. Beneficial effect of pesticides on growth and development of sugarcane appears largely on account of more efficient utilisation of soil and fertilizer nitrogen. The results raise an interesting possibility of using these pesticides as growth stimulators to increase the efficiency of sugarcane plants growing under sub-optimal conditions of nitrogen  相似文献   
99.
In vitro clonal propagation of guava Banaras local was achieved by culturing nodal explants of mature trees on Murashige and Skoog (MS) revised medium supplemented with 4.5 M 6-benzyladanine (BA) alone or in combination with either 0.6 M indole-3-acetic acid (IAA), 0.5 M indole-3-butyric acid (IBA) or 0.3 M gibberellic acid (GA3). Multiple shoots were induced to form by enhancement of axillary branching and BA (4.5 M) without any auxin and gibberellin was found to give best shoot multiplication rate. In this medium 3–6 shoots developed on explants collected from field-grown plants and 5–10 shoots developed on explants taken from in vitro proliferated shoots within 12 wk of culture. A prior transfer of shoot clumps to a medium containing a lower concentration of BA (0.5 M) before harvesting of cuttings for rooting allowed rapid extension growth and increased the number of usable shoots per culture. Adventitious rooting occurred after subculturing excised shoots on a medium containing 1/2 strength MS salts, 1.5% sucrose, 1 M each of IBA and -naphtha-leneacetic acid (NAA), and 1 gl-1 activated charcoal. Regenerated plantlets were successfully established on soil.  相似文献   
100.
Piracetam is the prototype of a new class of psychotropic drugs, the nootropic agents, which are claimed to selectively improve the higher telencephalic integrative activities. The effect of piracetam on rat brain monoamines and prostaglandins (PGs) was assessed so as to garner information on its mode of action. Two doses of the drug were used, a lower dose (20 mg/kg ip) and a higher dose (100 mg/kg, ip), the latter being known to exert a facilitatory effect on learning and memory. Piracetam produced a dose-related effect on rat brain serotonin (5HT) and noradrenaline (NA), with the lower dose inducing a decrease in 5HT levels and an increase in NA concentrations. The higher dose of piracetam produced the opposite effect. Dopamine (DA) levels were not significantly affected. The lower dose of the drug attenuated 5HT turnover and augmented that of NA, whereas the higher dose of piracetam produced the reverse effects, in clorgyline treated rats. The lower dose of piracetam produced a slight and statistically insignificant increase in rat brain PGE2 and PGF2 alpha. However, the higher dose of the drug produced marked increase in the levels of both the PGs. The observed biochemical effects may provide a basis for the nootropic effect of piracetam. However, they may also be due to the GA-BA-mimetic action of the drug, particularly those observed with the lower dose of piracetam.  相似文献   
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