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Stan Matthews 《Annals of botany》2009,104(7):vii-viii
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Steven E. Clemants 《Brittonia》1982,34(4):477-477
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A north Florida population of Odontomachus brunneus, a species of ponerine ants, was studied for a one-year period to determine the annual cycle of reproduction and colony growth,
including the foraging biology and seasonal changes in nest architecture. The life cycle of O. brunneus is strongly seasonal. Colonies produce brood for 6 months and are broodless for 6 months. Alates are produced in mixed broods
at the beginning of each season, consuming much of the colony’s energy reserves. These reserves recover slowly through foraging
during the summer’s worker production, and rapidly after brood production ceases in October. The foraging population was estimated
to average 77% (SD 22) of the workforce. This proportion was not related to colony size and female alates were also found
to forage. Nest architecture was found to change seasonally, with winter nests being more than twice as deep as the average
summer nest. 相似文献
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C P Bianchi 《Life sciences》1990,47(8):PL23-PL24
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Marck KW 《Plastic and reconstructive surgery》2003,111(5):1702-1707
Noma (necrotizing ulcerative stomatitis, stomatitis gangrenosa, or cancrum oris) is a devastating orofacial gangrene that occurs mainly among children. The disease has a global yearly incidence of 140,000 cases and a mortality rate of approximately 90 percent. Patients who survive noma generally suffer from its sequelae, including serious facial disfigurement, trismus, oral incontinence, and speech problems. The medical history of noma indicates that the disease was already known in classical and medieval civilizations in Europe. In the sixteenth and seventeenth centuries, Dutch chirurgeons clearly described noma as a clinical entity and realized that the popular name "water canker" was not sufficient, because this quickly spreading ulceration in the faces of children was different from "cancer." In the eighteenth century, awareness that noma is related to poverty, malnutrition, and preceding diseases such as measles increased in northwestern Europe. In the first half of the nineteenth century, extensive surgical procedures were described for the treatment of the sequelae of noma. At the end of that century, noma gradually disappeared in the Western world because of economic progress, which gave the poorest in society the opportunity to feed their children sufficiently. Only in the twentieth century were effective drugs (sulfonamides and penicillin) against noma developed, as well as adequate surgical treatment for the sequelae of noma. These modes of treatment remain inaccessible for the many present-day victims of noma because of their extreme poverty. The only truly effective approach to the problem of noma throughout the world is prevention, namely, combating the extreme poverty with measures that lead to economic progress. In the meantime, medical doctors in the Western world should not forget their own history and ignore this global health problem; rather, they should face "the face of poverty" with the eyes of mercy and concern suited to their profession. 相似文献
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HANSON RP 《Bacteriological reviews》1952,16(3):179-204