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Otitic hydrocephalus as a complication of otitis media is probably not so rare as is generally assumed. The onset is insidious and first symptoms are vague. Even after signs of elevated cerebrospinal fluid pressure appear, differential diagnosis remains a difficult problem. On the basis of what is known of the pathologic features and clinical course of otitic hydrocephalus a plan for the prevention and management of this complication is suggested. In children and adolescents with a history of recurrent otitis media and other conditions likely to produce hydrocephalic disturbances, new episodes of otitis media must be treated along classical lines, notwithstanding supplementary use of antibiotics. After recovery, extended follow-up observation is required, which should include repeated ophthalmoscopic examinations. A finding of changes in the eyegrounds calls for neurologic evaluation. Energetic treatment, particularly daily spinal taps, may prevent ultimate blindness.  相似文献   
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SUMMARY: Calcium alginate wool swabs were no more efficient or reliable than gauze or absorbent cotton wool swabs when tested on drinking glasses infected with known numbers of bacteria. The number of bacteria left on the glass after swabbing was determined by a modified roll tube method.  相似文献   
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The development of Catananche caerulea pollen grains from theearly free microspore stage to the formation of the male germunit has been studied using the scanning electron microscope.The differentiation of the elaborate ectexine from primexineand the accompanying cytoplasmic changes in the microsporesare described. Changes in the tapetum, reflecting first theformation of sporopollenin precursors and then of pollenkitt,are also described. The origin of taxonomically important featuresis discussed. Catananche caerulea, Compositae: Lactuceae, microspore mitosis, male germ unit, ontogeny, primexine differentiation, scanning electron microscopy  相似文献   
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Contarinia tritici emerges the same year as the larvae are in the wheat ears and up to 3 years later. Its parasites emerge up to 2 years after the larvae are in the wheat ears, but never the same year. This indicates that the supernumerary generation of C. tritici that occurs on couch grass in August and September may be expected to be free from parasites and so constitutes a dangerous source of replenishment of the pest.
Emergence of Sitodiplosis mosellana can take place after the larvae have been in the soil up to twelve winters. Most of any one year's larvae do not necessarily emerge as midges after one winter, although usually this is so. Any one year's flight is probably a composite one derived from several previous generations of this one-generation-a-year gall midge.  相似文献   
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