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61.
目的了解急性重度眼烧伤的临床特点、预后及并发症发生情况。方法对笔者单位病案室保存的1977--2002年住院眼烧伤患者135例(155只眼)的病历进行回顾性统计分析。分析不同深度、原因眼烧伤的眼表修复率、修复时间、致盲情况及并发症。结果治疗后Ⅲ度眼烧伤的修复时间短于Ⅳ度眼烧伤,其修复率也明显高于Ⅳ度眼烧伤(P〈0.01);在不能修复的Ⅳ度眼烧伤中,酸烧伤致角膜穿孔6只眼,显著高于碱烧伤(1只眼,P〈0.05)。Ⅲ度眼烧伤视力≥0.05者有38只眼,〈0.05者51只眼;Ⅳ度眼烧伤视力≥0.05者0只眼,〈0.05着66只眼。78只酸、碱烧伤眼中,52只眼致盲,致盲率为66.7%;77只热烧伤眼中,65只眼致盲,致盲率为84.4%。Ⅲ度眼烧伤的并发症发生率低于Ⅳ度眼烧伤。其中Ⅲ度眼烧伤角膜穿孔、睑球粘连的发生率(1.1%、36.O%)均显著低于Ⅳ度眼烧伤(27.3%、59.1%,P〈0.01)。在酸烧伤患者中,角膜穿孔及睑外翻的发生率(29.2%、37.5%)较高。而热烧伤患者中眼睑球粘连的发生率(53.2%)较高。结论Ⅳ度眼烧伤伤后的预后差,致盲率高。目前的治疗方法尚不能完全改善其视功能及预后,有待进一步研究。 相似文献
62.
Oral self-administration and operant tasks have been used successfully to confirm ethanol′s positive reinforcing effects
in rats. However, in flavor conditioning tasks, ethanol is typically found to have aversive effects. The present studies explored
this apparent paradox by examining the change in value of a flavor paired with orally self-administered ethanol in two different
limited-access procedures. Rats were food-deprived and trained to drink (experiment 1) or to barpress for (experiment 2) 10%
(v/v) ethanol during daily 30-min sessions using prandial initiation techniques. All rats were then exposed to a differential
flavor conditioning procedure in which banana or almond extract was added to the drinking solution. One flavor (counterbalanced)
was always mixed with ethanol (CS+), whereas the other flavor was mixed with water (CS–). By the end of conditioning, rats
in both experiments drank more flavored ethanol than flavored water, confirming ethanol’s efficacy as a reinforcer. Moreover,
barpress rates for CS+ exceeded those for CS– in the operant task. Ethanol doses self-administered in final sessions averaged
about 1 g/kg. The effect of the flavor-ethanol contingency was assessed in preference tests that offered a choice between
the two flavor solutions without ethanol. In both experiments, subjects developed a preference for the flavor that had been
paired with ethanol. Thus, the outcome of flavor conditioning was consistent with that of the oral self-administration tasks
in providing evidence of ethanol’s rewarding effects. These experiments confirm and extend previous studies showing that flavor
aversion is not the inevitable result of flavor-ethanol association in rats. It seems likely that ethanol’s nutrient and pharmacological
effects both contributed to the development of conditioned flavor preference.
Received: 15 February 1997 / Final version: 11 June 1997 相似文献
63.
Neerja Sharma 《Early child development and care》1990,58(1):71-79
The infant is the youngest but perhaps the most valuable member of society. It has been unequivocally established through research that the period up to two years is the most potent for forming and establishing the basis of later development. This paper summarizes the findings of two research studies on infant care in India that began in July 1988 and culminated in March 1989 under my guidance. The two studies are linked in their final implications for infant stimulation and in their role in providing insights into changing trends in infant-care in India.
In study I patterns of infant caregiving practiced by fathers were investigated. Study II looked into infant-care practices in Punjabi families where the grandmother lived with the young parents. 相似文献
In study I patterns of infant caregiving practiced by fathers were investigated. Study II looked into infant-care practices in Punjabi families where the grandmother lived with the young parents. 相似文献
64.
活性炭纤维在地方性氟中毒方面的应用展望 总被引:1,自引:0,他引:1
介绍了活性炭纤维(ACFs)的制造,特性及其应用。它具有优异的结耕与性能特征。含碳量高,比表面积大,微孔丰富,从而吸附力强,而且活性炭纤维还可制成纱、布、毡等形状,它可用于去除燃煤氟中毒区室内空气中氟化氢、二氧化硫、氧化氮、氨等污染物,利用它的高吸附性能还可较好的去除饮水中的氟化物及其他有害物质。活性炭纤维是一种新型高效吸附材料。在氟中毒防治方面有广阔的前途。 相似文献
65.
There is a scarcity of well-controlled studies of the seasonal variation in circadian rhythmicity. In the present study, the circadian phase of rectal temperature and the onset of slow wave sleep were studied in a series of twelve 24-h experiments, one each month of the year, for six healthy subjects under controlled conditions in a climatic chamber. In winter, as compared with summer, the average circadian rhythm of rectal temperature was phase delayed by 45 min, and the average onset of slow wave sleep was phase delayed by 40 min. The temporal relationship between the circadian phase of rectal temperature and the timing of slow wave sleep was maintained throughout the year. Habitual rising and retiring times covaried as well. Furthermore, the circadian rhythm of rectal temperature followed the timing of the photoperiod across the year, but had a much smaller range of seasonal variation. Apparently, the seasonal variation in the photoperiodic zeitgeber is largely compensated for by the stabilizing influence of secondary zeitgebers. However, in healthy subjects some effect of photoperiodic variation can still be observed. 相似文献
66.
67.
68.
目的 :研究肺表面活性物质 (PS)治疗新生儿呼吸窘迫综合征 (NRDS)前后血管内皮分泌功能变化及可能的治疗机理。方法 :用PS制剂固尔苏治疗 18例NRDS患儿 ,于治疗前 3 0min ,治疗后 1、 6、 12、 2 4h ,用硝酸还原酶法测定NO (一氧化氮 )、放射免疫法测定ET (内皮素 )、 6 K PGF1α (6 酮前列环素 )。结果 :固尔苏治疗后患儿NO、 6 K PGF1α明显升高 ,ET明显下降 ,与治疗前比较有显著性差异 (P <0 0 1)。治疗后 1、 6、 12、 2 4hNO、6 k PGF1α、ET各组间两两比较无明显差异 (P >0 0 5 )。结论 :PS治疗NRDS的机理可能是通过改善血管内皮功能发挥作用 ,为用外源性NO吸入和静注前列环素辅助治疗NRDS提供可能的实验依据。 相似文献
69.
Identification of Babesia bigemina infected erythrocyte surface antigens containing epitopes conserved among strains 总被引:4,自引:0,他引:4
SANKALE SHOMPOLE TERRY F. McELWAIN DOUGLAS P. JASMER STEPHEN A. HINES JOSEPH KATENDE ANTHONY J. MUSOKE FRED R. RURANGIRWA TRAVIS C. McGUIRE 《Parasite immunology》1994,16(3):119-127
The presence of previously uncharacterized antigens (new antigens) on the surface of intact erythrocytes infected with three strains of Babesia bigemina from Kenya and one each from Puerto Rico, Mexico, St. Croix, and Texcoco-Mexico was demonstrated by indirect immunofluorescent antibody (IFA) reactions. These antigens were not strain specific because antibodies in bovine immune serum to either the Mexico or Kenya isolates reacted with all seven strains tested. Homologous and heterologous immune serum antibodies bound a maximum of 83% and 55%, respectively, of intact erythrocytes infected with the Kenya-Ngong strain but not uninfected erythrocytes. Both sera caused agglutination of only infected erythrocytes. Antibodies eluted from the surface of glutaraldehyde (0.25%) fixed infected erythrocytes had IFA reaction patterns among strains similar to those of immune sera before elation. Eluted antibodies were used to determine if these antigens were protein and encoded by B. bigemina. Eluted antibodies bound seven parasite-encoded proteins of 240, 220, 66, 62, 58, 52 and 38 kDa in an erythrocyte surfacespecific immunoprecipitation reaction of 35-methionine labelled proteins. It was concluded that the surface of B. bigemina infected erythrocytes had parasite-encoded proteins and that these proteins had surface exposed epitopes that were conserved among the seven strains examined which were from two continents. 相似文献
70.