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31.
32.
A field study was carried out to unravel the inter-specific differences in cotton for the partitioning of N, P, K, S, Ca,
Mg, Na and Cl from the subtending leaves to the reproductive parts of Gossypium hirsutum, G. barbadense and G. arboreum at various developmental stages. Results revealed significant differences among the species for the various parameters studied.
Overall there was a greater fresh and dry matter yield of various reproductive parts and subtending leaves of G. hirsutum and G. barbadense than G. arboreum, although the leaf photosynthetic rate was similar. Age-dependent increase in leaf area/leaf mass ratio indicated a greater
partitioning of earlier acquired assimilates to the growth of reproductive parts. Results indicated greater partitioning of
N, P, S and Ca during later reproductive growth (from boll production to its opening) in G. hirsutum and G. barbadense but during earlier reproductive growth in G. arboreum (from bud up to flower formation) as was evident by decreased subtending leaf/reproductive parts ratio. It is concluded that
better N, P, S and Ca partitioning ability of G. hirsutum and G. barbadense at the onset of boll development played a major role in the better yield and good quality fiber characteristics.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
33.
Stefan Salzbrunn Golam Rasul G. K. Surya Prakash George A. Olah 《Journal of molecular modeling》2000,6(2):213-216
Structures and energies of XH4
+ and XH6
+ (X = B, Al and Ga) have been calculated at the density functional theory (DFT) B3LYP/6-311++G(3df,2pd) level. Calculations indicate that although the structure with a three center two electron (3c-2e) bond is the global minimum for BH4
+, the global minima of AlH4
+ and GaH4
+ are not those with one 3c-2e bond, but those with two 3c-2e bonds. For calibration, both structures of AlH4
+ were also calculated at the ab initio CCSD(T)/cc-pVTZ level and results in agreement with the DFT results were found. Similar calculations also indicate that although the C2v symmetrical structure with two 3c-2e bonds is the global minimum for BH6
+, the global minima of AlH6
+ and GaH6
+ are not the C2v symmetrical structures with two 3c-2e bonds but the C2 symmetrical structures with three 3c-2e bonds.Electronic Supplementary Material available. 相似文献
34.
R. Bilal G. Rasul M. Arshad K. A. Malik 《World journal of microbiology & biotechnology》1993,9(1):63-69
Root colonization studies, employing immunofluorescence and using locally isolated strains, showed thatEnterbacter sp. QH7 andEnterobacter agglomerans AX12 attached more readily to the roots of most plants compared withAzospirillum brasilense JM82. Heat treatment of either root or inoculum significantly decreased the adsorption of bacteria to the root surface. Kallar grass and rice root exudates sustained the growth ofA. brasilense JM82,Enterobacter sp. QH7 andE. agglomerans AX12 in Hoagland and Fahraeus medium. All the strains colonized kallar grass and rice roots in an axenic culture system. However, in studies involving mixed cultures,A. brasilense JM82 was inhibited byEnterobacter sp. QH7 in kallar grass rhizosphere and the simultaneous presence ofEnterobacter sp. QH7 andE. agglomerans AX12 suppressed the growth ofA. brasilense JM82 in rice rhizosphere. The bacterial colonization pattern changed from dispersed to aggregated within 3 days of inoculation. The colonization sites corresponded mainly to the areas where root mucigel was present. The area around the point of emergence of lateral roots usually showed maximum colonization. 相似文献
35.
We describe the development and validation of a new, simple, sensitive and cost‐effective method for the determination of ceftriaxone in commercial formulations and spiked human plasma. The method proposes the conversion of ceftriaxone into a fluorescent product by reacting with ortho‐phthalaldehyde (OPA) in the presence of sulfite at room temperature. The reaction medium is buffered to pH 10 using borate buffer. The derivatized reaction product is highly fluorescent and exhibits maximum fluorescence intensity at λem = 386 nm after excitation at λex = 324 nm. The experimental parameters affecting progress of the derivatization reaction were carefully studied and optimized. Under optimum experimental conditions, the method has an excellent correlation coefficient of 0.9984 with a broad linear range of 0.4?20 µg/mL. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 1.30 × 10?3 and 3.90 × 10?3 µg/mL, respectively. The interference effects of common excipients on the quantification of drug were investigated and no interference effect was observed. The proposed method has been successfully applied to the determination of ceftriaxone in pharmaceutical formulations and spiked human plasma samples. The method has been validated statistically through percent recovery studies using standard addition and by comparison with a reference HPLC method. The developed method exhibits excellent inter‐ and intraday precision. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
36.
Grover Minakshi Ali Sk. Z. Sandhya V. Rasul Abdul Venkateswarlu B. 《World journal of microbiology & biotechnology》2011,27(5):1231-1240
Increased incidences of abiotic and biotic stresses impacting productivity in principal crops are being witnessed all over
the world. Extreme events like prolonged droughts, intense rains and flooding, heat waves and frost damages are likely to
further increase in future due to climate change. A wide range of adaptations and mitigation strategies are required to cope
with such impacts. Efficient resource management and crop/livestock improvement for evolving better breeds can help to overcome
abiotic stresses to some extent. However, such strategies being long drawn and cost intensive, there is a need to develop
simple and low cost biological methods for the management of abiotic stress, which can be used on short term basis. Microorganisms
could play a significant role in this respect, if we can exploit their unique properties of tolerance to extremities, their
ubiquity, genetic diversity, their interaction with crop plants and develop methods for their successful deployment in agriculture
production. Besides influencing the physico-chemical properties of rhizospheric soil through production of exopolysaccharides
and formation of biofilm, microorganisms can also influence higher plants response to abiotic stresses like drought, chilling
injury, salinity, metal toxicity and high temperature, through different mechanisms like induction of osmo-protectants and
heat shock proteins etc. in plant cells. Use of these microorganisms per se can alleviate stresses in crop plants thus opening
a new and emerging application in agriculture. These microbes also provide excellent models for understanding the stress tolerance,
adaptation and response mechanisms that can be subsequently engineered into crop plants to cope with climate change induced
stresses. 相似文献
37.
Khan M Ding C Rasul A Yi F Li T Gao H Gao R Zhong L Zhang K Fang X Ma T 《International journal of biological sciences》2012,8(4):533-547
Isoalantolactone, a sesquiterpene lactone compound possesses antifungal, antibacteria, antihelminthic and antiproliferative activities. In the present study, we found that isoalantolactone inhibits growth and induces apoptosis in pancreatic cancer cells. Further mechanistic studies revealed that induction of apoptosis is associated with increased generation of reactive oxygen species, cardiolipin oxidation, reduced mitochondrial membrane potential, release of cytochrome c and cell cycle arrest at S phase. N-Acetyl Cysteine (NAC), a specific ROS inhibitor restored cell viability and completely blocked isoalantolactone-mediated apoptosis in PANC-1 cells indicating that ROS are involved in isoalantolactone-mediated apoptosis. Western blot study showed that isoalantolactone increased the expression of phosphorylated p38 MAPK, Bax, and cleaved caspase-3 and decreased the expression of Bcl-2 in a dose-dependent manner. No change in expression of phosphorylated p38 MAPK and Bax was found when cells were treated with isoalantolactone in the presence of NAC, indicating that activation of these proteins is directly dependent on ROS generation. The present study provides evidence for the first time that isoalantolactone induces ROS-dependent apoptosis through intrinsic pathway. Furthermore, our in vivo toxicity study demonstrated that isoalantolactone did not induce any acute or chronic toxicity in liver and kidneys of CD1 mice at dose of 100 mg/kg body weight. Therefore, isoalantolactone may be a safe chemotherapeutic candidate for the treatment of human pancreatic carcinoma. 相似文献
38.
Background
Efficacy of high-dose vitamin A (VA) in children suffering from severe acute malnutrition (SAM) has recently been questioned. This study compared the efficacy of a single high-dose (200,000 IU) in addition to daily low-dose (5000 IU) VA in the management of children suffering from SAM with diarrhea and/or acute lower respiratory tract infection (ALRI).Methods
In a randomized, double-blind, controlled clinical trial in icddr,b, Bangladesh during 2005–07, children aged 6–59 months with weight-for-height <−3 Z-score and/or bipedal edema (SAM) received either a high-dose VA or placebo on admission day. Both the groups received 5,000 IU/day VA in a multivitamins drop for 15 days and other standard treatment which is similar to WHO guidelines.Results
A total 260 children (130 in each group) were enrolled. All had diarrhea, 54% had concomitant ALRI, 50% had edema, 48.5% were girl with a mean±SD age of 16±10 months. None had clinical signs of VA deficiency. Mean±SD baseline serum retinol was 13.15±9.28 µg/dl, retinol binding protein was 1.27±0.95 mg/dl, and pre-albumin was 7.97±3.96 mg/dl. Median (inter quartile range) of C-reactive protein was 7.8 (2.1, 22.2) mg/L. Children of the two groups did not differ in any baseline characteristic. Over the 15 days treatment period resolution of diarrhea, ALRI, edema, anthropometric changes, and biochemical indicators of VA were similar between the groups. The high-dose VA supplementation in children with SAM did not show any adverse event.Conclusions
Efficacy of daily low-dose VA compared to an additional single high-dose was not observed to be better in the management of children suffering from SAM with other acute illnesses. A single high-dose VA may be given especially where the children with SAM may leave the hospital/treatment center early.Trial Registration
ClinicalTrials.gov NCT00388921相似文献39.
IY Nikitina NA Kondratuk GA Kosmiadi RB Amansahedov IA Vasilyeva VV Ganusov IV Lyadova 《PloS one》2012,7(8):e43733
Background
Effector CD4 T cells represent a key component of the host’s anti-tuberculosis immune defense. Successful differentiation and functioning of effector lymphocytes protects the host against severe M. tuberculosis (Mtb) infection. On the other hand, effector T cell differentiation depends on disease severity/activity, as T cell responses are driven by antigenic and inflammatory stimuli released during infection. Thus, tuberculosis (TB) progression and the degree of effector CD4 T cell differentiation are interrelated, but the relationships are complex and not well understood. We have analyzed an association between the degree of Mtb-specific CD4 T cell differentiation and severity/activity of pulmonary TB infection.Methodology/Principal Findings
The degree of CD4 T cell differentiation was assessed by measuring the percentages of highly differentiated CD27low cells within a population of Mtb- specific CD4 T lymphocytes (“CD27lowIFN-γ+” cells). The percentages of CD27lowIFN-γ+ cells were low in healthy donors (median, 33.1%) and TB contacts (21.8%) but increased in TB patients (47.3%, p<0.0005). Within the group of patients, the percentages of CD27lowIFN-γ+ cells were uniformly high in the lungs (>76%), but varied in blood (12–92%). The major correlate for the accumulation of CD27lowIFN-γ+ cells in blood was lung destruction (r = 0.65, p = 2.7×10−7). A cutoff of 47% of CD27lowIFN-γ+ cells discriminated patients with high and low degree of lung destruction (sensitivity 89%, specificity 74%); a decline in CD27lowIFN-γ+cells following TB therapy correlated with repair and/or reduction of lung destruction (p<0.01).Conclusions
Highly differentiated CD27low Mtb-specific (CD27lowIFN-γ+) CD4 T cells accumulate in the lungs and circulate in the blood of patients with active pulmonary TB. Accumulation of CD27lowIFN-γ+ cells in the blood is associated with lung destruction. The findings indicate that there is no deficiency in CD4 T cell differentiation during TB; evaluation of CD27lowIFN-γ+ cells provides a valuable means to assess TB activity, lung destruction, and tissue repair following TB therapy. 相似文献40.