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901.
Aedes triseriatus pupae, host-seeking, and ovipositing females were collected at a southern Wisconsin site endemic for La Crosse encephalitis virus. The host-seeking and ovipositing females were age-graded by the Detinova and Polovodova techniques, respectively. Wing lengths were determined for all mosquitoes. Wing lengths of the mosquitoes collected as pupae were predicted from pupal weight by a simple regression equation. There was significant seasonal variation in body size of adult females, but no strong evidence that increased size was advantageous to survival. It is concluded therefore that the potential length of infective life is not affected by the size of the adult female.  相似文献   
902.
Detection of the carrier state of X-linked retinoschisis   总被引:8,自引:0,他引:8  
We determined the extent of suppressive rod-cone interaction in 11 obligate carriers and eight potential carriers of X-linked retinoschisis from eight families. Despite otherwise normal ophthalmoscopic and functional testing, all of the obligate heterozygous carriers demonstrated a complete absence of normal rod-cone interaction. Of the potential heterozygous carriers, three had normal rod-cone interactions, two had no detectable interaction, and two yielded technically unsatisfactory results. This lack of rod-cone interactions allows heterozygous individuals to be identified clinically and has implications concerning the origin of this inherited disorder.  相似文献   
903.
904.
Failure of patient-triggered ventilation in very immature infants may be due to the use of inappropriate triggering systems. Two types of airflow trigger were therefore compared consecutively to an airway pressure (SLE) triggering system. Each comparison was made in 10 infants, ≤28 weeks of gestation. Comparison was made of the delivered volume, trigger performance and blood gases using each system for 1 h. Both comparisons showed that the airflow triggering systems performed better: one (Draeger Babylog 8000) had a higher sensitivity ( p < 0:01) and the other (Bird VIP airflow trigger), in which inflation was terminated by sensing a reduction in inspiratory flow, had a lower degree of asynchrony ( p < 0:01) and a tendency to deliver higher volumes. These results suggest that triggering systems sensing airflow changes may be superior to those sensing airway pressure changes in very immature infants. The use of a mechanism to synchronize the termination of inflation to the end of the patient's inspiration may offer further advantages.  相似文献   
905.
The practice of school nursing must change with the times. School nurses must develop new leadership and collaborative skills to work within the interdisciplinary school and community teams that will be required to put changes in place. This article defines current trends and their implications for the search for the most efficient and appropriate school health services. It explores preparation and competencies for school nurses, legal and ethical concerns, and financing needed to provide adequate school health services. Many support systems exist today, and new ones are being developed to expand the range of health services provided in schools. The National Association of School Nurses encourages strategic planning for the new school health environment, and the Office of School Health at the University of Colorado provides extensive resources to help school nurses develop and put their plans in place.  相似文献   
906.
907.
908.
909.
An evaluation of treatment results of unstable spine fractures using the Harrington instruments in 37 patients has been performed. The described method can result in anatomical restoration of the vertebral canal. If vertebral canal lumen is not restored, anterior decompression should be performed making possible removal of posteriorly dislocated bone fragments. The earlier anterior decompression, the greater chance of improvement of neurological conditions. The described procedure is especially useful in fractures with partial palsy. After treatment 70 per cent of the patients with partial palsy resumed their normal lives.  相似文献   
910.
The details of two consecutive groups of cleft palate patients treated with one- or two-stage palate repair are presented. The total number of patients is 237, with 128 operated in one stage, and 109 operated in two stages. In the two-stage group, the frequency of 'unintended' palatal fistulas decreased by 80%, and the use of blood transfusions was greatly reduced, but total operation time and hospital stay were longer. The results in terms of speech quality, facial growth and dental occlusion, will be reported on separately.  相似文献   
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