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排序方式: 共有93条查询结果,搜索用时 31 毫秒
61.
Dayananda Siddavattam Elisha R. Raju Mike Merrick 《Pesticide biochemistry and physiology》2006,86(3):146-150
Parathion hydrolase (PH), also known as organophosphorus acid anhydrase, hydrolyses the triester linkage found in organophosphates including organophosphate pesticides and the nerve gas sarin. The enzyme is reported to be membrane-associated and the immature protein has a signal sequence of 29 amino acids. In experiments designed to examine the post-translational processing of the enzyme and to assess the distribution of the precursor and mature forms of the protein, we induced expression of the Flavobacterium balustinum PH structural gene, opd, in Escherichia coli strain BL21. Western blotting revealed that the induced PH was predominantly membrane-associated in E. coli but a protein band equivalent in size to mature PH was also found to be induced specifically in periplasmic fractions. This periplasmic protein was not PH, as it did not cross-react in Western blots, and N-terminal sequencing of the induced protein showed it to have 100% homology to the outer membrane protein OmpF. 相似文献
62.
The aim of this study was to investigate the effects of suppression of plasma prolactin (PRL) concentration on circulating concentrations of luteinizing hormone (LH), progesterone (P(4)), estradiol (E(2)beta), pause days and egg production in birds later in the reproductive period. Twenty-four White Leghorn birds of same age group were divided into two groups of 12 in each. Birds of each group were administered s/c either with placebo (control group) or equal volumes of anti PRL agent (2-bromo-alpha-ergocriptine) solution containing at 100 microg/kg body weight/hen/week (treated group) from 72 to 82 weeks of age. Egg production and inter sequence pauses were recorded daily from both the groups. Plasma PRL, LH, E(2)beta and P(4) concentrations were estimated in blood samples collected at weekly intervals. At 77th weeks of age, blood samples from treated and control birds were obtained every 3h for 36h to study the surges of LH. It was found that plasma PRL concentration was lower (p<0.01) in bromocriptine treated birds with high concentrations of LH, its 3h LH surges, E(2)beta and P(4) in plasma. Higher egg production, less pause days in treated birds may be the result of low PRL concentration, associated with positively correlated responses of high concentrations of LH (with regular interval and duration of LH surges), E(2)beta and P(4) concentration required for completion of egg formation and oviposition. In conclusion, bromocriptine administration decreased (p<0.01) PRL concentration increased (p<0.01) steroid hormones and LH surges, for egg formation and oviposition and enabled the birds to lay more eggs even later in the productive period with the available resources under normal husbandry practices. 相似文献
63.
Leishmaniasis, a vector-borne parasitic disease resulting from infection of macrophages by obligate intracellular parasites of genus Leishmania, has been considered a major tropical disease by the World Health Organization. Generic pentavalent antimonials have been the mainstay for therapy in the endemic regions because of its efficacy and cost effectiveness. However, the growing incidence of resistance for the pentavalent antimony complex in endemic and non-endemic regions has seriously hampered their use in these regions. The second line drugs such as amphotericin B, paromomycin and miltefosine are the other alternatives, but they merely fulfill the desired requirements of a safe drug. The recent researches focused on plants have shown a wise way to get a true and potentially rich source of drug candidates against leishmaniasis, where alkaloids have been found more effective. The present review initially highlights the current status of leishmaniasis, synergy of the disease with HIV, therapeutic options available and in later sections summarizes all alkaloids, which have shown significant antileishmanial activities. 相似文献
64.
BACKGROUND: Sorption‐desorption processes govern the movement of pesticides in soil. These processes determine the potential hazard of the pesticide in a given environment for groundwater contamination and need to be investigated. RESULTS: In the present study, sorption‐desorption processes of benfuracarb were investigated using a batch method in two mollisols. The kinetics of benfuracarb sorption in mollisols conformed to two‐compartment (1 + 1) first‐order kinetics. The fast sorption rate constant was about 3 times higher for silt loam than for loam soil. However, the slow sorption rate constants were statistically similar for both soils. The concentration‐dependent sorption‐desorption isotherms of benfuracarb could not closely conform to the Freundlich isotherm in mollisols of high organic C content. The computed values of both the sorption (log K) and desorption (log K′) capacities were higher for silt loam than for loam soil. The desorption index (n′/n) values in the range 30.0–41.3 indicated poor reversibility of sorbed benfuracarb in mollisols. CONCLUSION: In view of the strong sorption of benfuracarb in mollisols with only partial desorption, the possibility of the leaching of soil‐applied benfuracarb to contaminate groundwaters appears to be low. Copyright © 2010 Society of Chemical Industry 相似文献
65.
B. Prakash S. K. Verma S. V. Rama Rao M. V. L. N. Raju S. S. Paul A. Kannan 《British poultry science》2020,61(1):26-32
ABSTRACT1. The aim of this study was to determine the nutritional status of backyard chickens reared under 4 different agro-climatic conditions (tropical, humid subtropical, cool-temperate and semi-arid) of India during different seasons of the year and to compare their nutritional status with those reared under confined feeding system (CFS). In each season, 15 adult and 15 grower chickens were slaughtered for collecting content of crop and gizzard to assess the nutritional status from different agro-climatic conditions.2. The dry matter content of crop and gizzard was higher (P < 0.01) in chickens reared under backyard conditions compared to those reared under CFS.3. Higher (P < 0.01) crop and gizzard contents were recorded during winter compared to the rainy season. The proportion of grains in the crop during summer and winter season was higher compared to rainy season. Further, there were more insects present in the crop during the rainy season and winter compared to summer.4. The proportion of insects was higher in chickens reared in humid, subtropical and cool temperate regions compared to semi-arid conditions. The consumption of grasses was higher in cool-temperate regions as compared to those reared under other areas.5. Crude protein (CP), Ca, P and gross energy (GE) content of the crop were higher in chickens reared under CFS compared to those reared in backyard systems and CP in the crop contents was lower in backyard chickens reared in humid subtropical and semi-arid regions compared to other areas. Similarly, lower (P < 0.01) Ca levels were seen in crop and gizzard contents from birds reared in semi-arid Rajasthan, and P and GE were lower in tropical wet and dry Telangana (TWT) compared to the chickens reared in the backyard conditions in other regions.6. Based on the results, the nutrient intake for birds utilising the scavenging feed resource base (SFRB) in the TWT region was below the requirements of backyard chickens from the other regions selected in the present study. GE and CP were critically deficient in the SFRB of the TWT region. Therefore, evolving location-specific supplementary diets using locally available feed resources to meet nutrient requirement of backyard chickens is required for optimising production potential. 相似文献
66.
Lee E Iskow R Yang L Gokcumen O Haseley P Luquette LJ Lohr JG Harris CC Ding L Wilson RK Wheeler DA Gibbs RA Kucherlapati R Lee C Kharchenko PV Park PJ;Cancer Genome Atlas Research Network 《Science (New York, N.Y.)》2012,337(6097):967-971
Transposable elements (TEs) are abundant in the human genome, and some are capable of generating new insertions through RNA intermediates. In cancer, the disruption of cellular mechanisms that normally suppress TE activity may facilitate mutagenic retrotranspositions. We performed single-nucleotide resolution analysis of TE insertions in 43 high-coverage whole-genome sequencing data sets from five cancer types. We identified 194 high-confidence somatic TE insertions, as well as thousands of polymorphic TE insertions in matched normal genomes. Somatic insertions were present in epithelial tumors but not in blood or brain cancers. Somatic L1 insertions tend to occur in genes that are commonly mutated in cancer, disrupt the expression of the target genes, and are biased toward regions of cancer-specific DNA hypomethylation, highlighting their potential impact in tumorigenesis. 相似文献
67.
Panda AK Rao SV Raju MV Niranjan M Reddy MR 《Tropical animal health and production》2012,44(2):293-299
A study was conducted to evaluate the effect of various concentrations of metabolizable energy (ME) with graded incremental
levels of crude protein (CP) and essential amino acids (lysine and methionine) on production performance, egg quality and
humoral immune response of Dahlem Red laying hens. Four experimental diets based on maize–soybean meal-deoiled rice bran were
prepared. Diet 1 was fed as a control diet containing 2,600 kcal ME/kg, 15% CP, 0.75% Lys and 0.36% Met, and in the other
three diets (D2, D3 and D4), concentrations of the above nutrients were increased by 2.5%, 5.0% and 7.5%, respectively. The
levels of Ca (3.5%) and available P (0.32) were constant in all the diets. Each diet was offered ad libitum from 28 to 40 weeks
of age to eight replicates containing six birds in each replicate. The egg production, egg weight and egg mass (in grams of
egg per hen per day) were not affected by increasing the nutrient density up to 7.5% (2,795 kcal ME/kg diet) compared to the
control group (2,600 ME/kg diet). However, feed consumption and feed efficiency (in grams of egg per gram of feed) were influenced
by the variation in the nutrient density of diets. As the nutrient density increased by 5% (2,730 ME/kg diet), birds consumed
significantly (P < 0.001) less feed. The birds in the 7.5% higher density group produced significantly (P < 0.05) higher egg mass per unit feed consumption compared to the control diet. Increasing nutrient density up to 7.5% had
no effect on relative weight of albumen, yolk or shell. The Haugh unit, yolk colour and shell thickness were also not affected
due to variation in the nutrient density. The humoral immune response measured at 34 and 40 weeks was progressively improved
by increasing the nutrient density up to 5%. Increasing the nutrient density beyond 5% in the diet had no further influence
on the humoral immune response. Based on the results of the present study, it can be concluded that Dahlem Red laying hens
required 2,795 kcal/kg ME, 16% CP, 0.8% lysine and 0.4% methionine for eliciting optimum performance and immune response during
28 to 40 weeks of age. 相似文献
68.
Sida cordifolia L., Croton bonplandianum L., Malachra capitata L., Eclipta prostrata L., Clerodendron inerme L., Acalypha indica L., and Urena lobata L. are common weeds found all over India. They are often infected by different begomovirus complexes and may act as reservoirs
of crop-infecting begomoviruses. Cloning and sequencing were done to partially characterize the begomovirus complexes associated
with these weed species from the eastern part of India and their genetic pattern was compared with respective geographical
isolates throughout India. Coat protein (CP) genes were found to be amplified from all the infected samples tested in this
study, whereas betasatellite molecules amplified only from four infected samples (Sida, Croton, Malachra and Urena). Sequence analysis using CP genes and betasatellites of the present begomovirus complexes showed significant variation among
their geographical isolates and also exhibited closeness to different crop-infecting begomovirus complexes. The majority of
the weed-infecting begomovirus complexes characterized in this paper are reported for the first time from India. 相似文献
69.
The ethanolic extracts of the leaves and flowers of Cleome viscosa and roots of Gmelina asiatica were tested for antimicrobial activity. The two plants exhibited a broad spectrum of antimicrobial activity, particularly significative against Escherichia coli , Proteus vulgaris and Pseudomonas aeruginosa. The leaf extract of C. viscosa showed moderate activity against pathogenic fungi. 相似文献
70.
Lakshminarayana R Raju M Krishnakantha TP Baskaran V 《Journal of agricultural and food chemistry》2005,53(8):2838-2842
Leafy vegetables [Basella rubra L., Peucedanum sowa Roxb., Moringa oleifera Lam., Trigonella foenum-graecum L., Spinacia oleracea L., Sesbania grandiflora (L.) Poir., and Raphanus sativus L.] that are commonly used by the rural population in India were evaluated in terms of their main carotenoid pattern. The extracted carotenoids were purified by open column chromatography (OCC) on a neutral alumina column to verify their identity by their characteristic UV-visible absorption spectra. Reverse-phase high-performance liquid chromatography (HPLC) on a C18 column with UV-visible photodiode array detection under isocratic conditions was used for quantification of isolated carotenoids. Acetonitrile/methanol/dichloromethane (60:20:20 v/v/v) containing 0.1% ammonium acetate was used as a mobile phase. The major carotenoids identified by both methods were lutein, beta-carotene, violaxanthin, neoxanthin, and zeaxanthin. Among the carotenoids identified, lutein and beta-carotene levels were found to be higher in these leafy vegetables. Results show that P. sowa and S. oleracea are rich sources of lutein (77-92 mg/100 g of dry wt) and beta-carotene (36-44 mg/100 g of dry wt) compared with other leafy vegetables. The purity of carotenoids eluted by OCC was clarified by HPLC, and they were found to be 92% +/- 3% for neoxanthin, 94% +/- 2% for violaxanthin, 97% +/-2% for lutein and zeaxanthin, and 90% +/- 3% for beta-carotene. It could be recommended to use P. sowa and S. oleracea as rich sources of lutein and beta-carotene for health benefits. The OCC method proposed is relatively simple and provides purified carotenoids for feeding trials. 相似文献