New phylum discovered, named     

Lewin R 《Science (New York, N.Y.)》1983,222(4620):149

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Extinctions and the History of Life: Now that, for many at least, asteroid impact has been accepted as a causative agent in mass extinction, attention turns to the wider view     

Lewin R 《Science (New York, N.Y.)》1983,221(4614):935-937

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The plasma state: physics of ion-ion and electron-ion collisions     

Flannery MR 《Science (New York, N.Y.)》1983,222(4626):922

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What Killed the Giant Mammals?: As the huge glacial masses of 10,000 years ago melted, dozens of species of giant mammals crashed into extinction: was the culprit climate or human hunter?     

Lewin R 《Science (New York, N.Y.)》1983,221(4615):1036-1037

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Communication between scientists     

Abelson PH 《Science (New York, N.Y.)》1983,221(4615):1011

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Soviets reject test ban changes     

Smith RJ 《Science (New York, N.Y.)》1983,220(4594):286-287

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Fossil lucy grows younger, again     

Lewin R 《Science (New York, N.Y.)》1983,219(4580):43-44

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Congenital esophagotracheal fistula as the cause of bloat in a calf     

Keane DP  Horney FD  Ogilvie TH 《The Canadian veterinary journal. La revue veterinaire canadienne》1983,24(2):57-59

A four day old Holstein calf was presented with a history of recurrent free gas bloat. An exploratory laparotomy was performed and no abnormalities were discovered in the gastrointestinal tract. An esophagotracheal fistula was suspected and confirmed by endoscopy. Surgical correction was performed by ligating the tubular connection between the trachea and esophagus and suturing closed the defects in these structures.  相似文献   

Esophageal ectasia in a quarterhorse colt     

Barber SM  McLaughlin BG  Fretz PB 《The Canadian veterinary journal. La revue veterinaire canadienne》1983,24(2):46-49

A one month old Quarterhorse colt was presented after a week history of bilateral nasal discharge and respiratory difficulty. The cervical esophagus was greatly dilated, tortuous and filled with diluted milk. A nasogastric tube could not be passed beyond the base of the heart. An aspiration pneumonia was found at postmortem examination and the esophageal segment from the pharynx to the base of the heart was dilated, thin-walled, had degenerative muscular changes, and a reduction in size and number of ganglion cells of the myenteric plexus. Muscular hypertrophy of the terminal esophagus had reduced its lumen size. Some similarities and disparities of this condition to achalasia of man and megaesophagus of dogs are discussed.  相似文献   

Selenium levels of beef cattle in southeastern british columbia relative to supplementation and type of pasture     

Fenimore RL  Adams DS  Puls R 《The Canadian veterinary journal. La revue veterinaire canadienne》1983,24(2):41-45

Moderate to extremely low levels of selenium in hay were related to marginally deficient levels of selenium in sera from cattle in the Windermere Valley of southeastern British Columbia. Deficiency was most pronounced in cattle fed local hay during the winter or grazed on fertilized/irrigated pastures. Cattle on range had adequate levels of serum selenium. When sodium selenite was fed at 1.0 and 3.5 mg per head per day, serum selenium levels increased commensurate with the dose. Clinical observations indicated that a variety of clinical problems disappeared after injection or supplementation with selenium/vitamin E.  相似文献