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121.
Summary The approximate analytical solution of Lane-Emden equation of index 5 has been found in the form of the rational function. The problem of the accuracy of this solution is briefly discussed. 相似文献
122.
V. K. Sharma 《Cellular and molecular life sciences : CMLS》1977,33(2):203-204
Summary The physiological and mutagenic actions of three alkylating agents have been studied on the process of nitrogen fixation byAnabaena doliolum Bharadwaja. The results show that these chemicals presumably switch off the activity of nitrogenase, resulting in the inhibition of fixation. 相似文献
123.
Zusammenfassung Die stickstoffhaltigen Exkretionsprodukte von Raupen vonManduca sexta L. wurden papierchromatographisch analysiert. Die wichtigsten ausscheidungsprodukte sind Harns?ure und Allantoin: Harnstoff
wird nur in Spuren ausgeschieden.
相似文献
124.
L. Singh T. Sharma S. P. Ray-Chaudhuri 《Cellular and molecular life sciences : CMLS》1968,24(1):79-80
Zusammenfassung Die diploide Chromosomenzahl beider Geschlechter beträgt 40: 10 Macrochromosomen und 30 Microchromosomen. Die GeschlechtschromosomenZZ () undZW () sind cytologisch erkennbar. 相似文献
125.
D. S. Bhakuni M. M. Dhar V. N. Sharma 《Cellular and molecular life sciences : CMLS》1968,24(2):109-110
Zusammenfassung Thespesin, der optisch aktive gelbe Farbstoff aus den Früchten derThespesia populens Soland hat eine dimere sesquiterpene-naphthalene Struktur, die mit dem optischen inaktiven Baumwollsamen-Farbstoff Gossypol identisch ist. Die optische Aktivität des Thespesin ist bedingt durch Atropisomerie.
Communication No. 1225 from the Central Drug Research Institute. 相似文献
Communication No. 1225 from the Central Drug Research Institute. 相似文献
126.
Molecular processes that govern pathogenic features of erythrocyte invasion and cytoadherence in malaria are reliant on Plasmodium-specific Duffy-binding-like domains (DBLs). These cysteine-rich modules recognize diverse host cell-surface receptors during pathogenesis. DBLs of parasite erythrocyte-binding proteins mediate invasion, and those from the antigenically variant P. falciparum erythrocyte membrane protein 1 (PfEMP1) have been implicated in cytoadherence. The simian and human malarial parasites, P. knowlesi and P. vivax, invade human erythrocytes exclusively through the host DARC receptor (Duffy antigen receptor for chemokines). Here we present the crystal structure of the P. knowlesi DBL domain (Pkalpha-DBL), which binds to DARC during invasion of human erythrocytes. Pkalpha-DBL retains the overall fold observed in DBLs from P. falciparum erythrocyte-binding antigen (EBA)-175 (ref. 4). Mapping the residues that have previously been implicated in binding highlights a fairly flat but exposed site for DARC recognition in subdomain 2 of Pkalpha-DBL; this is in sharp contrast to receptor recognition by EBA-175 (ref. 4). In Pkalpha-DBL, the residues that contact DARC and the clusters of residues under immune pressure map to opposite surfaces of the DBL, and suggest a possible mechanism for immune evasion by P. vivax. Our comparative structural analysis of Pkalpha-DBL and P. falciparum EBA-175 provides a framework for the understanding of malaria parasite DBLs, and may affect the development of new prophylactic and therapeutic strategies. 相似文献
127.
128.
Kaushal S Ghosh S Sharma N Sanyal SN Majumdar S 《Cellular and molecular life sciences : CMLS》2001,58(14):2098-2107
A 36-kDa phospholipid transfer protein (PLT-PR), which preferentially transfers phosphatidyl choline (PC) compared to phosphatidyl inositol (PI), was purified 827-fold
from rabbit lung homogenate. Incorporation of cholesterol in unilamellar vesicles reduced the PC transfer activity of PLTPR. Dipalmitoyl phosphatidyl choline uptake by alveolar type II cells was increased in the presence of the protein, and further
enhanced in the presence of surfactant liposomes. However, a decrease in uptake was noted with cholesterol in host membranes.
Incorporation of PI into host membranes had a low stimulatory effect on the process. All these effects were more pronounced
in adult type II cells compared to premature, term and 3-day-old pups.
Received 12 September 2001; accepted 11 October 2001 相似文献
129.
Sharma RP Ogale SB Zhang ZH Liu JR Chu WK Veal B Paulikas A Zheng H Venkatesan T 《Nature》2000,404(6779):736-740
The growing body of experimental evidence for the existence of complex textures of charges and spins in the high-temperature superconductors has drawn attention to the so-called 'stripe-phase' models as a possible basis for the mechanism of superconductivity in these materials. Such observations have until now been restricted to systems where the texture dynamics are slow or suppressed altogether, and do not include the important case of YBa2Cu3O(7-delta). It seems likely that the dynamic behaviour of stripes, which has been suggested to undergo several phase transitions as a function of temperature, should also be reflected in the lattice properties of the host materials, and this forms the motivation for our present experiments. Specifically, we use MeV helium ion channelling, an ultrafast real-space probe of atomic displacements (with sub-picometre resolution), to probe incoherent lattice fluctuations in YBa2Cu3O(7-delta) as a function of temperature and oxygen doping. We detect lattice fluctuations that are larger than the expected thermal vibration component, and which show anomalies characteristic of the phase transitions anticipated for a dynamic stripe phase. Comparison of our lattice results with single-particle-tunnelling and photoemission data highlights the importance of spin-charge separation phenomena in the copper oxide superconductors. 相似文献
130.