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881.
The Shoshone sculpin ( Cottus greenei ) is found only in springs of the Thousand Springs formation along the Snake River in Idaho. In 1983 a small population of Shoshone sculpin was introduced into an unnamed spring in the Thousand Springs formation in an attempt to increase the range of the species. Previously, the only sculpin in that spring was the mottled sculpin ( Cottus bairdi ). The Shoshone sculpin was able to establish itself and become the predominant fish within 8 years. 相似文献
882.
Mount Rainier National Park, with an area of 95,356 ha, is approximately one-third as large as the state of Rhode Island. The lowest point is 490 m in elevation in the southeastern corner near where the Ohanapecosh River crosses the southern boundary. Columbia Crest is the highest point at 4392 m. The entire park is a rugged landscape marked by the major topographical feature, Mount Rainier, comprising over 25,899 ha, almost one-third of the park. The park lies entirely west of the crest line of the Cascade Range. Most streams in the park originate on Mount Rainier; however, several large rivers meander through the park near its boundaries. One of the first attempts to summarize the stoneflies of Washington, including Mount Rainier National Park, was Hoppe's 1938 work that reported ca 8 species. Jewett (1959) reviewed the stoneflies of the Pacific Northwest and listed 7 species that had type localities in the park: Megaleuctra kincaidi Frison, Doddsia occidentalis (Banks), Soliperla fenderi ( Jewett), Frisonia picticeps (Hanson), Isoperla rainiera Jewett, Megarcys irregularis (Banks), and M. subtruncata (Hanson). Subsequently, Kathroperla takhoma Stark and Surdick (1987) was described from the park. Samples of adult stoneflies from 1994 to 2001 indicate the presence of at least 82 species, with 64% of these typical Pacific Northwest species, and 30 species, or 36%, widespread western North American species. Seventeen new Washington state records are listed, including a substantial range extension for Lednia tumana (Ricker). One undescribed species in the Sweltsa borealis complex was also discovered. We also present illustrations of male terminalia for Despaxia augusta (Banks) and Moselia infuscata (Claassen) to aid in the identification of these species. 相似文献
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A cycle of activity of aldehyde-fuchsin and performic acid-Victoria blue positive granules was observed in the ovarian pedicle of Dysdercus koenigii during the first ovipositional cycle. The quantitative variation of these granules in the pedicle can also be correlated directly with the increase or decrease of the neurosecretory material in the A-type cells of the pars intercerebralis medialis region of the protocerebrum of the brian. 相似文献
887.
Ionophores consist of molecules which surround and carry positive metal ions and other ions through biological membranes.
One classe of ionophores which we have been developing contains dipeptides which are encouraged to become part of a ring because
of possible hydrogen bond formation between the 2-hydroxy on the phenyl group and carboxyl group (COOH) of the final amide
proline. Formation of a ring should increase the complexation ability of the ionophore. We report that the synthesis of N-(2-hydroxyl-1-phenoxyacetyl)
prolyproline(1), a novel ionophore is prepared from activated 2-acetoxy phenoxyacetic acid (3a) and the appropriate dipeptide
ester using coupling methods such as dicyclohexyl carbodiimide with hydroxyben-ztriazole or carbonyl diimidazole.
Yang Dingqiao: born in 1958, Associate professor 相似文献
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