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排序方式: 共有838条查询结果,搜索用时 15 毫秒
831.
832.
C. S. Nair I. Singh M. S. Malhotra A. Dasgupta S. K. Dass 《International journal of biometeorology》1977,21(4):332-336
Seven lowlander soldiers who had 1st to 3rd degree of frostbite and 8 lowlander soldiers who recovered from high altitude pulmonary oedema were tested for cold pressor response at 260 m, 26°C, 6.8°C and 4,085 m, 26°C, 6.8°C. 8 lowlander soldiers (Control subjects) of comparable age group were tested for their cold pressor response at 260 m, 26°C and 3,300 m, 26°C. Another group of control subjects from the laboratory were also tested at 2,121 m, 26°C. There was a highly significant decrease in cold pressor response of the frostbite subjects at 260 m, 26°C and a very significant increase at 260 m, 6.8°C as compared to non-frostbite subjects. The subjects who recovered from high altitude pulmonary oedema did not show significant differences as compared with the control subjects. The results suggest certain basic physiological differences in regulation of supply of blood to the extremities under condition of general and local cold exposure. 相似文献
833.
Several HindIII monomer units of a tandemly repeated nuclear DNA sequence ofBrassica campestris andBrassica juncea (Cruciferae) have been cloned and sequenced. The monomer units, of 177 bp length, are AT-rich and share 88% homology between themselves and more than 65% homology with similar repeats of otherCruciferae likeBrassica oleracea, Sinapis alba andRaphanus sativus. Thus unlike the rapid divergence of tandemly repeated satellite DNA in other organisms, this DNA element is highly conserved thus indicating its importance. 相似文献
834.
835.
Somsankar Dasgupta Edward L. Hogan Herman van Halbeek 《Journal of neurochemistry》1995,65(5):2344-2349
Abstract: Our studies of bovine brain neutral glycosphingolipids (Ngsls) have revealed the presence of several short-chain (containing -CHO 1–4) and previously uncharacterized long-chain (−CHO > 4–5) Ngsls. We reported the structural characterization of brain GgOse4 Cer (GA1) and have now purified another brain Ngsl to homogeneity. The purified Ngsl migrated close to standard GgOse4 Cer and nLcOse5 Cer on a TLC plate employing two different solvent systems. The carbohydrate molar composition indicated the presence of Gal/Glc/GalNAc in a ratio of 2.8:1.0:0.9. Five permethylated alditol acetate peaks were characterized as 2,3,4,6-OMe4 Gal, 2,4,6-OMe3 Gal, 2,3,6-OMe3 Gal, 2,3,6-OMe3 Glc, and 4,6-OMe2 GalNAcMe by gas chromatography-mass spectrometry. The anomeric carbohydrate sequence has been determined by specific exoglycosidase digestion. Six-hundred megahertz 1 H NMR spectroscopy of the oligosaccharide released by ceramide glycanase hydrolysis confirmed the structure of the Ngsl as Galβ1-3GalNAcβ1-3Galα1-4Galβ1-4Glc\1-1Cer or IV3 GalGbOse4 Cer. Using the immunooverlay technique with anti-stage-specific embryonic antigen 3 antibody, it was found in bovine, rat, and normal adult human brain and bovine myelin, but not in human or rat myelin. 相似文献
836.
Gross changes of myelinated fibres and Schwann cells at different degenerative stages were present in all five ENL nerve lesions. Besides these changes, infiltrating cells mainly macrophages, deposition of excessive collagen and perineurial vessel damage were also observed. 相似文献
837.
838.