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161.
Self‐Powered Wireless Sensor Node Enabled by an Aerosol‐Deposited PZT Flexible Energy Harvester 下载免费PDF全文
162.
163.
D Subrahmanyam V M Sarma A Venkateswarlu T V Sastry A P Kulakarni D S Rao K V Reddy 《Bioorganic & medicinal chemistry》1999,7(9):2013-2020
A number of 5-aminosubstituted 20(S)-camptothecin analogues were prepared via semi-synthesis starting from 20(S)-camptothecin and 9-methoxy 20(S)-camptothecin. In vitro anti-cancer activity of these analogues was determined using 60 human tumor cell line assay. Although water solubility of most of these compounds was improved compared to 20(S)-camptothecin, their anti-cancer activity was considerably diminished. However, only smaller substituents such as methylamine or hydroxylamine as present in 8s and 8t, respectively, showed good activity with improved water solubility. 相似文献
164.
G. Venkateswarlu P. S. Murali Gita Sharma L. Venkateswar Rao 《Bioprocess and biosystems engineering》2000,23(4):315-318
Two mutant strains of Amycolatopsis mediterranei VA17 and VA18 were isolated using physical (UV) and chemical (NTG) mutagens gave high rifamycin B than the parent type when grown in the same fermentation medium with a pH of 7.2, temperature 32v°C for a period of 12 days. The cultural conditions of both mutant strains are similar to the parent strain except temperature which was higher by 4v°C. By this mutation and selection study, rifamycin B production was improved from 1400 mg/l to 2450 mg/l. 相似文献
165.
P.J. J.R. Bottomley J.S. Reynolds T.J. McNulty K. Venkateswarlu B.V.L. Potter C.E. Dempsey P.J. Cullen 《Current biology : CB》1997,7(12)
Inositol 1,3,4,5-tetrakisphosphate (IP4), is a ubiquitous inositol phosphate that has been suggested to function as a second messenger. Recently, we purified and cloned a putative IP4 receptor, termed GAP1IP4BP[1], which is also a member of the GAP1 family of GTPase-activating proteins for the Ras family of GTPases. A homologue of GAP1IP4BP, called GAP1m, has been identified [2] and here we describe the cloning of a GAP1m cDNA from a human circulating-blood cDNA library. We found that a deletion mutant of GAP1m, in which the putative phospholipid-binding domains (C2A and C2B) have been removed, binds to IP4 with a similar affinity and specificity to that of the corresponding GAP1IP4BP mutant. Expression studies of the proteins in either COS-7 or HeLa cells showed that, whereas GAP1IP4BP is located solely at the plasma membrane, GAP1m seems to have a distinct perinuclear localisation. By mutational analysis, we have shown that the contrast in subcellular distribution of these two closely related proteins may be a function of their respective pleckstrin homology (PH) domains. This difference in localisation has fundamental significance for our understanding of the second messenger functions of IP4. 相似文献
166.
The colchicine amphiploid (2n=72) of the hybridSolanum nodiflorum (2n=24)×S. villosum (2n=48) was crossed toS. memphiticum (2n=72) and toS. nigrum (2n=72). In the resulting F1 hybrids chromosome numerical mosaicism was observed in the anthers of some plants. It was found that chromosome mosaicism did not affect chromosome pairing in normal cells. Disharmonious gene combination seems to be responsible for premeiotic somatic instability which results in chromosome mosaicism observed during meiosis in pollen mother cells. Gene or genes for fertility are transmitted independent of those for chromosome stability. It is suggested thatS. nigrum andS. memphiticum possess in common a gene complex, which when combined withS. nodiflorum andS. villosum genomes will induce somatic instability. 相似文献
167.
In this review we have described data supporting the conclusion that PtdIns(3,4,5)P3 may regulate the activation state of ARF6 through an ability to recruit the ARF exchange factors ARNO, GRP1 and cytohesin-1 to the plasma membrane. The downstream consequences of such a PtdIns(3,4,5)P3-dependent activation of ARF6 are presently unclear. However, given the role of ARF6 in fusion events at the plasma membrane, we have proposed that PtdIns(3,4,5)P3 may regulate vesicle trafficking at this membrane through its ability to activate ARF6. This is an attractive possibility given the number of PtdIns(3,4,5)P3-dependent pathways which involve some aspect of vesicle trafficking at the plasma membrane, for instance glucose transport, membrane ruffling and cell movement. 相似文献
168.
The interaction effects of insecticide combinations involving an organophosphate (monocrotophos or quinalphos) and a pyrethroid (cypermethrin or fenvalerate) were determined on the growth ofScenedesmus bijugatus (unicellular green alga) andSynechococcus elongatus (unicellular cyanobacterium). In general, an organophosphate and a pyrethroid in combinations interacted additively, antagonistically, and synergistically on the growth of the two phototrophic microorganisms. However, combinations of quinalphos and cypermethrin or fenvalerate yielded additive interaction response in onlyS. bijugatus. 相似文献
169.
Kolla J P Narayana Peddikotla Prabhakar Muvva Vijayalakshmi Yenamandra Venkateswarlu Palakodety S J Krishna 《Polish journal of microbiology》2008,57(1):35-39
An attempt was made to study the bioactive compounds from a terrestrial Streptomyces sp. ANU 6277 isolated from laterite soil. Four active fractions were recovered from the solvent extracts obtained from the culture broth of five day-old strain. Three bioactive compounds were purified and identified as 3-phenylpropionic acid, anthracene-9,10-quinone and 8-hydroxyquinoline. The components of the partially purified fourth active fraction were analyzed by gas chromatography-mass spectrometry and identified as benzyl alcohol, phenylethyl alcohol and 2H-1, 4-benzoxazin-3 (4H)-one. Four active fractions were screened for antimicrobial activity against Gram-positive and Gram-negative bacteria, and fungi including phytopathogenic, toxigenic and dermatophytic genera. Among these metabolites, 8-hydroxyquinoline exhibited strong antibacterial and antifungal activity as compared to 3-phenylpropionic acid and anthracene-9,10-quinone. 相似文献
170.
Venkateswarlu D Krishnaswamy S Darden TA Pedersen LG 《Journal of molecular modeling》2002,8(10):302-313
Trocarin belongs to group D of prothrombin activators derived from snake venom of Tropidechis carinatus and is a rich non-hepatic source of Xa, the only known hepatic prothrombin activator. The structural and functional similarity with Xa makes trocarin an interesting target for exploring the structure-functional relationship with Xa. Herein we report a predicted complete three-dimensional all-atom structural model of trocarin equilibrated in explicit water using 4 ns of molecular dynamics simulation. The tertiary structure was modeled using the structure of human blood coagulation factor Xa. The conformational and structural features of trocarin are then compared with the X-ray crystal and solution simulation structures of human factor Xa. The modeled structure of trocarin has four individual domains (Gla, EGF1, EGF2 and SP) connected along the long axis with similar secondary structural elements to Xa. The simulations suggest that sodium ion binding in the serine protease domain is impaired in trocarin as compared to Xa. In contrast to Xa, for which the sodium ion forms an octahedral coordination network that brings two loop regions connecting four anti-parallel beta-sheets together, we do not find a similar pattern of network in trocarin. We observe that the difference in the binding pattern of sodium ion leads to a approximately 2-A "shrinkage" of the beta2 strand (B2), in comparison to human Xa, as marked by a shorter distance between 189Asp373 (S1-site residue) and 195Ser379 (active-site residue) in the B2 strand. We propose that these differences may be linked to the experimentally observed lower amidolytic activity of trocarin as compared to Xa. 相似文献