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991.
O. L. Nesterova 《Entomological Review》2007,87(7):822-829
A comparative morphological characteristic of the mouthparts of representatives of five Palaearctic genera of the subtribe Entomoscelidina is given. 相似文献
992.
R. R. Yadav 《Journal of biosciences》2009,34(5):699-707
Tree-ring analyses from semi-arid to arid regions in western Himalaya show immense potential for developing millennia long
climate records. Millennium and longer ring-width chronologies of Himalayan pencil juniper (Juniperus polycarpos), Himalayan pencil cedar (Cedrus deodara) and Chilgoza pine (Pinus gerardiana) have been developed from different sites in western Himalaya. Studies conducted so far on various conifer species indicate
strong precipitation signatures in ring-width measurement series. The paucity of weather records from stations close to tree-ring
sampling sites poses difficulty in calibrating tree-ring data against climate data especially precipitation for its strong
spatial variability in mountain regions. However, for the existence of strong coherence in temperature, even in data from
distant stations, more robust temperature reconstructions representing regional and hemispheric signatures have been developed.
Tree-ring records from the region indicate multi-century warm and cool anomalies consistent with the Medieval Warm Period
and Little Ice Age anomalies.
Significant relationships noted between mean premonsoon temperature over the western Himalaya and ENSO features endorse utility
of climate records from western Himalayan region in understanding long-term climate variability and attribution of anthropogenic
impact. 相似文献
993.
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996.
Soluble guanylate cyclase enzyme was purified from human platelets. The soluble fraction of the lysed platelets was sequentially chromatographed over DEAE-sepharose, GTP-agarose and HPLC size-exclusion columns. About 0.1 mg of purified enzyme could be obtained from 2000 ml of platelet rich plasma. The purified enzyme had the specific activity of 205 nmoles cGMP/mg/min with Mn2+ as cofactor. The enzyme eluted at the 160,000 daltons position from the size-exclusion column. Electrophoresis in the presence of sodium dodecyl sulfate under reducing conditions revealed two subunits of 83,000 and 71,000 daltons respectively. 相似文献
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999.
Two cases of squamous cell carcinoma of the prepuce arising on balanitis xerotica obliterans are described. This event is unusual and not well known. The surgical treatment was a wide circumcision in which the prepuce and part of the shaft skin were removed, performing as well a decortication of the glans base. This technique seemed to be satisfactory in removing the carcinoma and obtaining a definite improvement in the clinical picture of balanitis xerotica obliterans as well. 相似文献
1000.
Revised Primary Structure for Human Growth Hormone 总被引:3,自引:0,他引:3
HUGH D. NIALL 《Nature: New biology》1971,230(11):90-91