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11.
Enhanced plant regeneration in grain and sweet sorghum by asparagine,proline and cefotaxime 总被引:7,自引:0,他引:7
Summary Cefotaxime ( 50 and 100 mg/1 ), a cephalosporin antibiotic and the amino acids asparagine and proline (200 mg/l) enhanced the production of embryogenic callus, increased the frequency of plant regeneration, and delayed the loss of regeneration potential in immature embryo-derived callus cultures ofSorghum bicolor (L.) Moench. Although these compounds did not promote callus induction or growth of callus, they influenced plant regeneration considerably in 10 low responding genotypes of grain and high anthocyanin containing sweet sorghums. 相似文献
12.
G Giordano G Peterson W J McMurray K Shyam A C Sartorelli 《Biological mass spectrometry》1991,20(11):693-698
A series of bis(sulfonyl)-1-methylhydrazines were analyzed by positive ion electron impact (EI), chemical ionization (CI) and fast atom bombardment (FAB) mass spectrometry. Since these compounds showed activity against the L1210 leukemia, an understanding of their mass spectral behavior is important should the structural characterization of metabolites be required. FAB proved to be the most useful technique, generally providing abundant protonated molecule ion peaks, in contrast to the weak peaks observed with CI (ammonia or isobutane) and the total absence of molecular ion peaks in the EI mass spectra. In addition, utilizing FAB eliminated the problem of thermal decomposition, which was very difficult to control under EI and CI experimental conditions. Fragments observed in FAB and CI mass spectra were consistent with protonation at the methyl-bearing nitrogen. One can locate the R1 and R2 moieties relative to the methyl-bearing nitrogen in FAB and CI by assigning that nitrogen as the site of protonation, with subsequent elimination of R2SO2H. 相似文献
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The present communication deals with the observations made on the morphology, reproduction and cytology ofUlothrix zonata (Weber & Mohr)Kütz. in culture. The alga displays a remarkable phenotypic plasticity in nature as well as in culture. The present study provides additional evidence of karyology in support ofLokhorst andVroman's treatment ofU. zonata which merges a number of earlier described species in it. The cytological details and chromosome number (n = 10) determined for the Indian isolates ofU. zonata agree with those ofSarma for the British material.NBRI Research Publication No. 63 (N.S.) 相似文献
15.
The present communication deals with the details of sexual reproduction including the process of fusion of gametes in Eudorina californica (Shaw) Goldstein (earlier described as E. indica lyengar). The present observations are compared with those on other species in which the process of fusion was recorded. 相似文献
16.
The distinctive morphological and karyological features of the two new species, collected from freshwater habitats in North India, are presented and compared with those of related taxa of the generaWoloszynskia andGymnodinium. Asexual reproduction takes place through zoospore formation and sexual reproduction through planozygotes inWoloszynskia stoschii. 相似文献
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18.
Anand Kumar Seema Singh Satyajit Pradhan Ram C Shukla Mumtaz A Ansari Tej B Singh Rohit Shyam Saroj Gupta 《World journal of surgical oncology》2007,5(1):1-6
Background
Von Hippel-Lindau (VHL) disease is an autosomal dominant inherited disease. It is relatively recent that type 2C was identified as a separate group solely presenting with pheochromocytomas. As an illustration, an interesting case is presented of a pregnant woman with refractory hypertension. It proved to be the first manifestation of bilateral pheochromocytomas. The family history may indicate the diagnosis, but only identification of a germ line mutation in the DNA of a patient will confirm carriership.Case presentation
A 27 year pregnant patient with intra uterine growth retardation presented with hypertension and pre-eclampsia. Magnetic resonance imaging revealed bilateral adrenal pheochromocytoma. She underwent laparoscopic adrenelectomy and a missense mutation (Gly93Ser) in exon 1 of the VHL gene on chromosome 3 (p25 - p26) was shown in the patient, her father and her daughter confirming the diagnosis of VHL.Conclusion
In almost all VHL families molecular genetic analysis of DNA will demonstrate an inherited mutation. Because of the involvement in several organs, periodic clinical evaluation should take place in a well coordinated, multidisciplinary setting. VHL disease can be classified into several subtypes. VHL type 2C patients present with pheochromocytomas without evidence of haemangioblastomas in the central nervous system and/or retina and a low risk of renal cell carcinoma. Therefore, in such families, periodic clinical screening can be focussed on pheochromocytomas. 相似文献19.
One of the most promising applications of nanomaterials is that of nanobiosensors, using biomolecules such as nucleic acids as receptors. This study aimed to synthesize nickel oxide nanoparticles (NiO NPs) by an environmentally friendly green synthesis, using the extract of the herb Coriandrum sativum (coriander). The synthesized NPs were characterized using UV–Visible spectroscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, X‐ray photon spectroscopy, field emission scanning electron microscopy coupled with energy dispersive spectroscopy, dynamic light scattering, zeta potential and transmission electron microscopy. All results confirmed the synthesis of pure, spherical, positively charged NiO NPs of around 95 nm in diameter with prominent hydroxyl groups attached to the surface. Furthermore, interaction studies of synthesized NiO NPs with calf thymus DNA (CT DNA) were performed using UV–Visible spectroscopy, UV–thermal melting, circular dichroism, and fluorescence spectroscopy. CT DNA served as a substitute for nucleic acid biosensors. All experimental studies indicated that the NiO NPs bound electrostatically with CT DNA. These studies may facilitate exploring the potential of NiO NP–nucleic acid conjugated materials to be used as nanobiosensors for various applications, especially in pharmacological, epidemiological, and environmental diagnostic applications, and in detection. 相似文献
20.
Kandasamy Thamilarasi Kumari Kanchan Ghosh Jyotirmoy Tribhuvan Kishor U. Lohot Vaibhav D. Gargi Madhuranjana Ghosal S. 《Journal of plant biochemistry and biotechnology.》2020,29(3):461-472
Journal of Plant Biochemistry and Biotechnology - Pigeonpea, an important legume crop is a good host plant for lac cultivation in North East India. In the present study, sixty-three polymorphic EST... 相似文献