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101.
Elham A. Ghabbour Ahmed H. Khairy Donald P. Cheney Verena Gross Geoffrey Davies Thomas R. Gilbert Xinyu Zhang 《Journal of applied phycology》1994,6(5-6):459-468
A standard humic acid extraction procedure has been used to isolate dark brown organic residues from samples of the macroscopic marine brown algaPilayella littoralis. The residues are insoluble in water, but soluble at high pH, and are similar in elemental composition, ash content, UV-visible, IR, PMR and X-Ray fluorescence spectra, X-Ray diffractograms and scanning electron micrographs to residues of a humic acid isolated from municipal compost. These results indicate thatPilayella produces humic acids.Author for correspondence 相似文献
102.
Plant regeneration via somatic embryogenesis in ginger 总被引:5,自引:0,他引:5
A. Kackar S. R. Bhat K. P. S. Chandel S. K. Malik 《Plant Cell, Tissue and Organ Culture》1993,32(3):289-292
Embryogenic callus cultures of ginger were induced from young leaf segments taken from in vitro shoot cultures. Among the four auxins tested in Murashige & Skoog medium, dicamba at 2.7 M was most effective in inducing and maintaining embryogenic cultures. Efficient plant regeneration was achieved when embryogenic cultures were transferred to Murashige & Skoog medium containing 8.9 M benzyladenine. Histological studies revealed various stages of somatic embryogenesis characteristic of the monocot system. The in vitro-raised plants have been established in soil.Abbreviations BA
benzyladenine
- 2,4-d
2,4-dichlorophenoxyacetic acid
- IAA
indole-3-acetic acid
- MS
Murashige and Skoog
- NAA
naphthaleneacetic acid 相似文献
103.
Summary The uterine cervix, urinary bladder and rectum of guinea pigs were injected with Fast Blue dye for retrograde transport studies. Dye-laden neuronal perikarya were detected for each viscus in the paracervical ganglion. These same perikarya also exhibited immunoreactivities for tyrosine hydroxylase, aromatic amino acid decarboxylase, dopamine -hydroxylase, neuropeptide Y, or vasoactive intestinal peptide, though the perikarya projecting to the urinary bladder did not exhibit immunoreactivity for aromatic amino acid decarboxylase. The results of this study indicate that the guinea-pig paracervical ganglion projects to viscera in addition to the uterus, and that the ganglion contains a range of immunoreactivities related to adrenergic and non-adrenergic neurotransmitters. 相似文献
104.
Mohsen A. F. El-Hazmi Hassan M. Bahakim Arjumand S. Warsy Abdulkarim Al-Momen Abdullah Al-Wazzan Ibrahim Al-Fawwaz Sameer Huraib Mohammad Harakati 《Molecular and cellular biochemistry》1993,124(1):17-22
Sickle cell anaemia (SCA) exhibits significant variations in clinical presentation in different populations for which several genetic factors including SCA-associated -and -thalassaemias, G-6-PD deficiency and elevated Hb F level have been implicated as possible ameliorating factors. Saudi Arabia is unique in that mild and severe forms of the disease occur at a high frequency. We investigated the G/A ratio and Hb F level and correlated these values with the severity of SCA. The results showed that Hb F level varies significantly in both groups of patients with no evident correlation with the mild clinical manifestations. However, G/A ratio correlated significantly with the disease severity where a high ratio was observed in patients with the mild and a low ratio in patients with the severe disease. The results are evaluated and discussed in the light of correlation studies and regression analysis. 相似文献
105.
Mohd Imran Shahzad Ahmed Ahmad Zuhairi Abdullah Jabir Hakami Anis Ahmad Chaudhary Hassan Ahmad Rudayni Salah-Ud-Din Khan Afzal Khan Nosiba Suliman Basher 《Luminescence》2023,38(7):1064-1086
The penicillin derivative amoxicillin (AMX) plays an important role in treating various types of infections caused by bacteria. However, excessive use of AMX may have negative health effects. Therefore, it is of utmost importance to detect and quantify the AMX in pharmaceutical drugs, biological fluids, and environmental samples with high sensitivity. Therefore, this review article provides valuable and up-to-date information on nanostructured material-based optical and electrochemical sensors to detect AMX in various biological and chemical samples. The role of using different nanostructured materials on the performance of important optical sensors such as colorimetric sensors, fluorescence sensors, surface-enhanced Raman scattering sensors, chemiluminescence/electroluminescence sensors, optical immunosensors, optical fibre-based sensors, and several important electrochemical sensors based on different electrode types have been discussed. Moreover, nanocomposites, polymer, and MXenes-based electrochemical sensors have also been discussed, in which such materials are being used to further enhance the sensitivity of these sensors. Furthermore, nanocomposite-based photo-electrochemical sensors and the market availability of biosensors including AMX have also been discussed briefly. Finally, the conclusion, challenges, and future perspectives of the above-mentioned sensing techniques for AMX detection are presented. 相似文献
106.
Gopinath Chattopadhyay Shahbaz Ahmed Nonavinakere Seetharam Srilatha Aparna Asok Raghavan Varadarajan 《Protein science : a publication of the Protein Society》2023,32(1):e4514
Regulation of biological processes by proteins often involves the formation of transient, multimeric complexes whose characterization is mechanistically important but challenging. The bacterial toxin CcdB binds and poisons DNA Gyrase. The corresponding antitoxin CcdA extracts CcdB from its complex with Gyrase through the formation of a transient ternary complex, thus rejuvenating Gyrase. We describe a high throughput methodology called Ter-Seq to stabilize probable ternary complexes and measure associated kinetics using the CcdA-CcdB-GyrA14 ternary complex as a model system. The method involves screening a yeast surface display (YSD) saturation mutagenesis library of one partner (CcdB) for mutants that show enhanced ternary complex formation. We also isolated CcdB mutants that were either resistant or sensitive to rejuvenation, and used surface plasmon resonance (SPR) with purified proteins to validate the kinetics measured using the surface display. Positions, where CcdB mutations lead to slower rejuvenation rates, are largely involved in CcdA-binding, though there were several notable exceptions suggesting allostery. Mutations at these positions reduce the affinity towards CcdA, thereby slowing down the rejuvenation process. Mutations at GyrA14-interacting positions significantly enhanced rejuvenation rates, either due to reduced affinity or complete loss of CcdB binding to GyrA14. We examined the effect of different parameters (CcdA affinity, GyrA14 affinity, surface accessibilities, evolutionary conservation) on the rate of rejuvenation. Finally, we further validated the Ter-Seq results by monitoring the kinetics of ternary complex formation for individual CcdB mutants in solution by fluorescence resonance energy transfer (FRET) studies. 相似文献
107.
Summary Regenerable embryogenic cell suspensions initiated from immature embryo-derived friable, fast growing, embryogenic calli of GK Ságvári winter wheat (Triticum aestivum L.) served as sources of protoplasts, which were cultured in different liquid or agarose-solidified media. Protocallus formation was best on KM8p (Kao and Michayluk 1975) and GM (Li and Murai 1990) media, and protocallus growth on MS (Murashige and Skoog 1962) callus growing medium. Green shoot/plant regeneration occurred on MS regenerating medium, and rooting on MS or N6M (Mórocz et al. 1990) hormone-free media. Protocalli maintained their morphogenic capacity over 4 months, and with multiple subcultures on half-strength MS regenerating medium, the total number of regenerants could be increased. Approximately 1000 shoots/plants were regenerated and over 500 plants were transplanted in the greenhouse. The majority of them had an abnormal chromosome number and low viability, however, one plant grew to maturity and set seed.Abbreviations BAP
6-benzylaminopurine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- ECS
embryogenic cell suspension
- GA3
gibberellic acid
- GM
General medium
- IAA
indole-3-acetic acid
- IBA
indole-3-butyric acid
- MS
Murashige and Skoog medium
- NAA
1-naphthaleneacetic acid
- RECS
regenerable embryogenic cell suspension 相似文献
108.
Munir Ozturk Mert Metin Volkan Altay Tomonori Kawano Alvina Gul Bengu Turkyilmaz Unal Dilek Unal Rouf Ahmad Bhat Moonisa Aslam Dervash Kristina Toderich Esra Koc Pedro Garcia Caparros leeb Shahzadi 《Phyton》2023,92(1):165-192
Aluminum is an abundant metal in the earth’s crust that turns out to be toxic in acidic environments. Many plants are affected by the presence of aluminum at the whole plant level, at the organ level, and at the cellular level. Tobacco as a cash crop (Nicotiana tabacum L.) is a widely cultivated plant worldwide and is also a good model organism for research. Although there are many articles on Al-phytotoxicity in the literature, reviews on a single species that are economically and scientifically important are limited. In this article, we not only provide the biology associated with tobacco Al-toxicity, but also some essential information regarding the effects of this metal on other plant species (even animals). This review provides information on aluminum localization and uptake process by different staining techniques, as well as the effects of its toxicity at different compartment levels and the physiological consequences derived from them. In addition, molecular studies in recent years have reported specific responses to Al toxicity, such as overexpression of various protective proteins. Besides, this review discusses data on various organelle-based responses, cell death, and other mechanisms, data on tobacco plants and other kingdoms relevant to these studies. 相似文献
109.
Md. Aktar-Uz-Zaman Md. Ariful Islam Md. Shahin Iqbal Md. Jahangir Alam Debashish Sarkar Bander Albogami Ahmed Gaber Akbar Hossain 《Phyton》2023,92(3):883-899
Ensuring food security for the rapidly increasing population and changing climatic scenarios are requisites for
exploiting the genetic divergence of food crops. A study was undertaken to sort out an early maturing chickpea
variety for fitting easily between rice-rice cropping systems in the Eastern Indo-Gangetic Plain of Bangladesh. The
trial was comprised of eight elite lines of chickpea and executed at various localities in Bangladesh from 2014–
15 to 2017–18. The result explored the chickpea genotype, BARI Chola-11 remained superior to the rest of
the elite genotypes for having a short maturity period (100–106 days), and lesser days to 50% flowering (47–
55 days). The same genotype was recorded to have robust vegetative and reproductive yield attributes including
plant height (49–57 cm), podsplant−1 (37–50), and optimum 100 seed weight (19.5–20.6 g). Owing to better yield
attributes, BARI Chola-11 resulted in the maximum seed yield (1200–1500 kg ha−1
) of chickpea and might be
recommended for general adoption in the region for boosting nutritional security status through improved productivity under changing climate. 相似文献
110.