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71.
72.
By means of a synoptophore vergence eye movements were recorded in dyslexic and normal children while they were attempting to track small targets moving in simulated depth. Of the dyslexic children 64% were unable to make proper vergence movements when macular sized fusion targets (2 1/2 degrees) were employed, but their vergence control was better for larger (7 degrees) targets. The normal readers and the remaining dyslexics showed normal vergence responses for both large and small moving fusion stimuli. The results suggest that many dyslexics suffer a disorder of visuomotor control and perception for stimuli falling on the macula; this may explain their characteristic visual problems when reading. Hence recording vergence eye movement responses to small moving fusion stimuli may be useful in the investigation and treatment of children with reading difficulties. 相似文献
73.
BACKGROUND. Temafloxacin is a new broad-spectrum arylfluoroquinolone antimicrobial with an extended serum half-life. METHODS. In this large, multicenter, double-blind clinical trial, 404 women with acute, uncomplicated urinary tract infections (UTI) were randomized to receive temafloxacin 400 mg once daily for 3 days, or ciprofloxacin 250 mg twice daily for 7 days. Clinical and microbiologic evaluations were repeated at 4 to 5 days after initiation of treatment, at the end of therapy, and at 5 to 9 days posttreatment. One hundred fifteen patients who received temafloxacin and 105 patients who received ciprofloxacin met the eligibility criteria for efficacy evaluation. The predominant urinary pathogens were Escherichia coli, Proteus mirabilis, and coagulase-negative staphylococci. No pretherapy isolate was resistant to either study drug. RESULTS. Bacteriologic eradication was observed in 112 (97%) of 115 women treated with temafloxacin and 101 (96%) of 105 women treated with ciprofloxacin. Clinical cure rates at 5 to 9 days posttreatment were 90% (the remaining 10% improved) with temafloxacin and 95% (the remaining 5% improved) with ciprofloxacin. Adverse effects associated with treatment occurred in 24 (12%) women who received temafloxacin and 31 (15%) women who received ciprofloxacin. Headache (2% with temafloxacin and 2% with ciprofloxacin), nausea (3% with temafloxacin and 6% with ciprofloxacin), and somnolence (4% with temafloxacin and 3% with ciprofloxacin) were reported most often. Only three and five patients who were treated with temafloxacin and ciprofloxacin, respectively, discontinued treatment because of adverse effects. CONCLUSIONS. In this study, a 3-day treatment regimen using a single daily 400-mg dose of temafloxacin was found to be as effective as a 7-day course of ciprofloxacin in women with acute uncomplicated UTI. 相似文献
74.
The insulinotropic potency of fatty acids is influenced profoundly by their chain length and degree of saturation. 总被引:16,自引:2,他引:14
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D T Stein B E Stevenson M W Chester M Basit M B Daniels S D Turley J D McGarry 《The Journal of clinical investigation》1997,100(2):398-403
Lowering of the elevated plasma FFA concentration in 18- 24-h fasted rats with nicotinic acid (NA) caused complete ablation of subsequent glucose-stimulated insulin secretion (GSIS). Although the effect of NA was reversed when the fasting level of total FFA was maintained by coinfusion of soybean oil or lard oil (plus heparin), the more saturated animal fat proved to be far more potent in enhancing GSIS. We therefore examined the influence of individual fatty acids on insulin secretion in the perfused rat pancreas. When present in the perfusion fluid at 0.5 mM (in the context of 1% albumin), the fold stimulation of insulin release from the fasted pancreas in response to 12.5 mM glucose was as follows: octanoate (C8:0), 3.4; linoleate (C18:2 cis/cis), 5.3; oleate (C18:1 cis), 9.4; palmitate (C16:0), 16. 2; and stearate (C18:0), 21.0. The equivalent value for palmitoleate (C16:1 cis) was 3.1. A cis--> trans switch of the double bond in the C16:1 and C18:1 fatty acids had only a modest, if any, impact on their potency. A similar profile emerged with regard to basal insulin secretion (3 mM glucose). When a subset of these fatty acids was tested in pancreases from fed animals, the same rank order of effectiveness at both basal and stimulatory levels of glucose was seen. The findings reaffirm the essentiality of an elevated plasma FFA concentration for GSIS in the fasted rat. They also show, however, that the insulinotropic effect of individual fatty acids spans a remarkably broad range, increasing and decreasing dramatically with chain length and degree of unsaturation, respectively. Thus, for any given level of glucose, insulin secretion will be influenced greatly not only by the combined concentration of all circulating (unbound) FFA, but also by the makeup of this FFA pool. Both factors will likely be important considerations in understanding the complex interplay between the nature of dietary fat and whole body insulin, glucose, and lipid dynamics. 相似文献
75.
76.
The RNase mismatch cleavage method was examined for its efficiency of indicating single-base sequence differences in the capsid protein-coding regions of different foot-and-mouth disease virus subtype O1 strains. The method was found suitable for indicating such differences. RNase A as well as RNase T1 contributed to substrate conversion. Examples for the cleavage of eleven different single-base mismatches in RNA double-strands are now known. All virus genomes found to differ from each other exhibited three or more non-neighboured single-base sequence differences. Other genomes found to be indistinguishable by this method were those of a recent field isolate adapted to cell culture, and those of a vaccine production strain; its progeny was transmitted to pig and cow and then analyzed. The results suggest that host change does not necessarily select for antigenic variant virus, and that virus submitted to some kind of selection pressure is changed at more than one position. 相似文献
77.
78.
A method for coating native, non-derivatized, polysaccharide (PS) onto nitrocellulose (NC) for identifying PS-specific antibodies has been developed. The new feature of this method is that PS molecules are vacuum filtered onto NC in their native state by devices that can accommodate NC of different sizes and shapes. PS-coated NC disks were used to localize antibody secreting hybridoma cells cultured on filter paper disks. These were analyzed by blotting with size-matched PS-coated NC disks and specific antibodies secreted by individual colonies were detected by enzyme-linked immunoblot. In another application of this method, immune sera were separated by isoelectric focusing and the gels were blotted with PS-coated NC sheets. The spectrotype and isotype of antibodies that bound to the NC were examined using isotype specific enzyme-linked antibody. These immunoblots showed high resolution and specificity. The advantages of this method are that the PS used for coating does not need to be derivatized in order to bind the NC, and that smaller quantities of PS may be utilized by this coating method when compared to other techniques. This provides a useful tool to ask many questions regarding the immune response to PS. 相似文献
79.
Roald Bahr Fernando Pena Joe Shine William D. Lew Conrad Lindquist Stein Tyrdal Lars Engebretsen 《Acta orthopaedica》1997,68(5):435-441
We analyzed the changes in lateral ligament forces during anterior drawer and talar tilt testing and examined ankle joint motion during testing, following an isolated lesion of the anterior talofibular ligament (ATFL) or a combined lesion of the ATFL and calcaneofibular ligament (CFL). 8 cadaver specimens were held in a specially designed testing apparatus in which the ankle position (dorsiflexion-plantarflexion and supination-pronation) could be varied in a controlled manner. Ligament forces were measured with buckle transducers, and joint motion was measured with an instrumented spatial linkage. An anterior drawer test was performed using an 80 N anterior translating force, and a talar tilt test was performed using a 5.7 Nm supination torque with intact ligaments, after sectioning of the ATFL, and again after sectioning of the CFL. The tests were repeated at 10° dorsiflexion, neutral, and 10° and 20° plantarflexion. In the intact ankle, the largest increases in ATFL force were observed during testing in plantarflexion, whereas the largest increases in CFL force were observed in dorsiflexion. Isolated ATFL injury caused only small laxity changes, but a pronounced increase in laxity was observed after a combined CFL and ATFL injury. 相似文献
80.
In a retrospective study we found that the incidence of gout in patients with Dupuytren's disease is 3.5%. The mean serum uric acid was 330 mumol/l. (5.5 mg./100 ml.) in men and 240 mumol./l. (4.0 mg./100 ml.) in women. The rate of hyperuricaemia was 7%. These are not significantly higher than the expected figures in Britain. 相似文献