摘要:

Experimental shock has been produced in the rat by clamping the hind legs. The mortality was related to the duration of limb ischaemia, as were the increased haemoglobin values. Adrenalectomized animals showed much greater susceptibility to trauma than did intact animals; DCA afforded no protection against trauma whereas adrenal cortical extract considerably improved the lowered tolerance. Conclusive evidence of development of resistance following repeated clamping was not obtained. Rats that had previously received a single clamping showed little evidence of resistance to drum trauma, whereas animals resistant to drumming showed increased tolerance when subjected to clamping.

ISSN:1923-4287    

DOI:10.1139/cjr47e-019

出版商:NRC Research Press    

年代:1947

数据来源: NRC

摘要:

In a survey of the wild rodents of Alberta it was found that 14 animals contained within their lungs fungous cells so large as to be visible to the naked eye. From the lungs of eight of these infected animals,Haplosporangium parvumwas obtained in culture. The position of the fungus among the Phycomycetes is confirmed by a study of the reproductive structures, which may be interpreted as sporangia containing one or, rarely, several spores.H.parvumgrows and sporulates upon soil. The sporangia are adhesive and transferred by contact. At 37 °C. they enlarge as much as 10 times their original diameter to form thick-walled chlamydospores that will germinate at room temperature. The parasite within the lung has a diameter as much as 50 times that of the sporangium from which it must have originated. Infected lungs usually show little reaction. Only one lung was frankly granulomatous. Some human systemic Phycomycetes, likeH.parvum, are filamentous in their saprophytic phase and unicellular in their parasitic phase. Three of them,Blastomyces dermatiditis,B.brasiliensis, andHistoplasma capsulatum, are closely related toH.parvum. In their saprophytic phase they all reproduce by adhesive conidia that may be interpreted as sporangia with single endospores, while in their parasitic phase no sporangia have been observed.Coccidioides immitisis less closely related toH.parvum. When growing saprophytically it reproduces by air-borne oidia; when growing parasitically, by endospores.

ISSN:1923-4287    

DOI:10.1139/cjr47e-020

出版商:NRC Research Press    

年代:1947

数据来源: NRC