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Regiospecific chemical methodologies have been developed for the incorporation of deuterium regio and stereospecifically in all four naturally occurring 2'-deoxynucleosides. 相似文献
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S. C. Pathak Vandana Kulshrestha Arun Kumar Choubey A. H. Parulekar 《Journal of biosciences》1999,24(2):233-240
Air borne insects, mostly carried by wind currents, were trapped over the northern Arabian sea (16‡ to 20‡ N; 68‡ to 72‡ E),
in the course of cruise No. 111, ORVSAGAR KANYA (March 14 to April 7, 1996). A total of 2,301 insects belonging to 8 different orders, 47 families and 173 species were trapped.
Of these, Hymenoptera was represented by the largest number (1082), which was followed by Hemiptera (586), Diptera (552),
Coleoptera (51), Neuroptera (10), Trichoptera (03), Lepidoptera (03) and Orthoptera (01). The trapped insects were mostly
between 0.6 mm to over 11 mm long. The data was examined for α-diversity as well as for possible correlations between various
parameters like the diversity index, size and number of insects trapped on one hand and the distance of the nearest land mass
in wind direction, on the other.
Deceased. 相似文献
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Albino guinea pigs were treated with psoralen derivatives plus 320--400 nm ultraviolet radiation, and DNA was extracted from their epidermis. The DNA was assayed for the presence of interstrand cross-links by standard denaturation-renaturation assays and by a new technique, electron microscopy of the DNA under totally denaturing conditions. The latter method allows individual cross-links to be directly observed and counted. When either 4,5',8-trimethylpsoralen or 8-methoxypsoralen was applied topically to the skin (8--20 microgram/cm2) or administered orally (10--12 mg/kg body weight), followed by exposure to 320--400 nm ultraviolet radiation, most of the epidermal DNA was found to contain a high frequency of cross-links. For example, oral or topical trimethylpsoralen treatment gave an average of one cross-link per 250 nucleotide pairs or about 3 . 10(5) cross-links per guinea pig chromosome. When the dose of either drug was decreased 20-fold to the level used in the clinical treatment of psoriasis, however, no cross-links coulld be detected in the epidermal DNA. The electron microscopic assay is sensitive enough that we can put an upper limit of 1 cross-link per 10(6) nucleotide pairs (80 cross-links per chromosome) for the low dose studies. The significance of these findings to the understanding of the effectiveness of psoralens in psoriasis therapy is discussed. 相似文献
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Pallab Ray Dr. Arunaloke Chakrabarti Manu Jatana B. S. Sharma A. Pathak 《Mycopathologia》1995,131(2):103-106
Western-blot immunoassay of cerebrospinal fluid (CSF) specimens of patients with central nervous system (CNS) aspergillosis (3), CNS candidosis (1) and bacterial meningitis (2) was carried out using pooled serum from histopathologically proven deep-seated aspergillosis cases to detect unique antigenic fractions for aspergillosis in CSF. No reactivity was observed in patients with non-fungal meningitis. Four cross-reactive bands (40, 90, 200 and >200 KD) were detectable in CSF from patients with both aspergillosis and candidosis of the CNS. Four additional bands (90–200 KD) were consistently present only in patients with aspergillosis. One prominent band (110 KD) was found only in the patient with aspergillosis who had a fatal outcome and raised the possibility of being a poor prognostic marker. 相似文献
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Using the silver staining technique, in somatic and meiotic chromosomes of the Armenian hamster (Cricetulus migratorius), it is possible to stain synaptonemal complexes (SCs) and the nucleolus organizer regions (NORs) in early spermatocytes. There are five pairs of autosomes (Nos. 2, 4, 6, 7, and 8) which have terminally located NORs. Synaptonemal complexes and accessory structures present in the sex chromosomes within the sex vesicle can be easily observed using light microscopy. 相似文献