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81.
We examined the preferences of female guppies (Poecilia reticulata) from 11 localities in Trinidad with respect to male color-pattern elements, body shape and size, and overall color and brightness contrast. Females are on average more attracted to males from their own population than from alien populations, and populations appear to vary in the criteria used in female choice. Multiple-regression analysis suggests that mate-preference criteria vary among localities in intensity, sign, and the number of traits used. Although preference estimators and color-pattern parameters are unique to each population, only orange, black, and color contrast showed a correlation between degree of male trait and degree of preference for that trait. There is a clear effect of water color and a possible effect of predation intensity. The results are discussed in light of various models of sexual selection and the early stages of speciation.  相似文献   
82.
Although avian color preferences have been studied and documented in controlled experiments, they have not been demonstrated under natural conditions in most cases. We hypothesized that avian fruit choice reflects intraspecific variation in fruit characteristics other than color, rather than fruit color differences. By planting one Ilex serrata Thunb. (red form) and one I. serrata forma leucocarpa Beissner (white form), which produce red and white fruits, respectively, at each of five points, we examined the proportion of fruits removed per tree and fruit choice by three avian species based on fruit color and other fruit characteristics. The proportion of fruits removed increased with pulpy sugar concentration and fruit diameter, but it did not differ between fruit colors. The main foragers, resident brown-eared bulbuls Hypsypetes amaurotis, consumed fruits regardless of color, but correspondingly to fruit removal, and appeared to base their fruit choice on pulpy sugar concentration and fruit diameter rather than on color. In contrast, the minor foragers, migrant Daurian redstarts Phoenicurus auroreus (Pallas) and Siberian bluechats Tarsiger cyanurus (Pallas), tended to choose red fruits and were possibly attracted by them. In conclusion, fruit removal per tree reflected individual variation in fruit profitability more strongly than differences in fruit color, even though the individual variation was not remarkable. The importance of color in fruit choice differed based on species, residency status, and major/minor foragers.  相似文献   
83.
1. We studied the effect of face cooling accompanied by a fall of tympanic temperature on color preference in 8 women at an ambient temperature of 28°C.2. The face only was cooled by blowing 15°C air at 6 m/s on the face only. Controls received either no wind at all or a wind (24°C, 6 m/s) on the body and appendages only.3. Most subjects preferred warmer colors after facial cooling than after no facial cooling.4. The facial cooling and decrease in tympanic temperature may indicate an increase in load error between core temperature and set-point.  相似文献   
84.
摘要目的:总结彩色多普勒超声引导下经皮肾镜取石术(percutaneous nephrolithotomy,PCNL) 治疗的复杂性肾结石的经验及其 安全性、有效性以及常见并发症。方法:回顾性分析我院2011 年7 月~2012 年8 月采用彩色多普勒引导下经皮肾镜治疗复杂性 肾结石患者56 例的临床资料。结果:所有患者均I期建立经皮肾通道,平均手术时间(107.5± 27.5)分钟,24 例行EMS 气压弹道联 合超声碎石(101.0± 27.9)分钟,20 例行钬激光联合超声碎石(119.4± 23.6)分钟,10 例行单纯超声碎石(108.2± 30.2)分钟,EMS 气 压弹道联合超声碎石组的手术时间少于钬激光碎石组,差异有统计学意义(P<0.05,单纯超声碎石组与另外两组比较无统计学意 义P>0.05)。术前肾功能损伤患者术后随访,肾功能明显改善。结石完全清除率91%,结石部分残留率9%。术中均无严重出血,无 周边脏器损伤。术后出现迟发出血5 例,反复发热4 例,均经对症治疗后缓解。结论:彩色多普勒超声引导除了具有普通超声引导 的优势外,还可有效避开肾实质大血管损伤,减少术中及术后出血风险。彩色多普勒超声引导下经皮肾镜碎石取石术是一种治疗 复杂性肾结石安全、有效的方法。  相似文献   
85.
Harmful Cochlodinium polykrikoides blooms have frequently appeared and caused fatal harm to aquaculture in Korean coastal waters since 1995. We investigated the applicability of GOCI, the world's first Geostationary Ocean Color Imager, in monitoring the distribution and temporal movement of a harmful algal bloom (HAB) that was discovered in the East Sea near the Korean peninsula in August 2013. We identified the existence of C. polykrikoides at a maximum cell abundance of over 6000 cells/mL and a chlorophyll a concentration of over 400 mg/m3. In areas of C. polykrikoides blooms, GOCI remote sensing reflectance (Rrs) spectra demonstrated the typical radiometric features of a HAB, and from the diurnal variations using GOCI-derived chlorophyll concentration images, we were able to identify the vertical migration of the red tide species. We also found that the formation and propagation of the HAB had relations with cold water mass in the coastal region. GOCI can be effectively applied to the monitoring of short-term and long-term movements of red tides.  相似文献   
86.
目的:探讨二维及彩色多普勒超声在乳腺癌诊断方面的临床应用价值。方法:对60例经手术病理证实的乳腺肿块病例的二维及彩色多普勒超声检查与病理结果进行回顾性分析。结果:乳腺癌诊断中,大多数恶性肿块表现为形态不规则、边缘粗糙、边界不清、内部回声不均匀、后方回声衰减。恶性肿块的血流显示率明显高,血流分布以Ⅱ、Ⅲ级为主。结论:二维声像图及彩色多普勒在乳腺癌诊断方面有较高的临床应用价值。由于良恶性肿物的影像互有交叉,其诊断符合率并非是100%。须两者联合应用,综合分析,方可提高超声对乳腺良恶性肿块的诊断符合率。  相似文献   
87.
黄岩  陈松旺  戴洁  张平洋 《生物磁学》2011,(6):1118-1120
目的:评价超声引导下股动脉假性动脉瘤瘤腔内注射凝血酶加加压治疗在治疗医源性股动脉假性动脉瘤中的应用价值。方法:在彩色多普勒超声引导下,采用20 G穿刺针经皮穿刺,对30例经股动脉介入治疗术后形成的股动脉假性动脉瘤患者行瘤腔内注射凝血酶封闭治疗同时行加压压迫治疗,凝血酶浓度为200 U/ml,总量均≤500 U,压迫治疗力量以病人能耐受,足背动脉搏动可触及为标准,加压时间为24小时。结果:30例患者均1次治疗成功,术中及术后无并发症发生,术后随访3个月无复发。结论:超声引导下股动脉假性动脉瘤瘤腔内注射凝血酶加加压治疗在治疗医源性股动脉假性动脉瘤中具有创伤小,操作简便,疗效确切的优点,可作为经股动脉介入治疗术后形成的假性动脉瘤的首选治疗方法。  相似文献   
88.
我国香芋资源极为丰富,但开发程度远不及山药、甘薯、马铃薯等,所以对香芋加工工艺的研究对其潜在价值的开发具有重要意义。通过单因素试验考察了烫漂温度、烫漂时间、进风温度、进料速度及料液浓度对香芋粉喷雾干燥的影响。试验确定了香芋粉喷雾干燥的最佳工艺为:55℃烫漂10 min、进风温度为180℃、进料速度50 mL/min、料液浓度为0.1 g/mL。  相似文献   
89.

Background

This study tested the hypothesis that the core interthreshold zone (CIZ) changes during exposure to red or blue light via the non-visual pathway, because it is known that light intensity affects the central nervous system. We conducted a series of human experiments with 5 or 10 male subjects in each experiment.

Methods

The air temperature in the climatic chamber was maintained at 20 to 24°C. The subjects wore suits perfused with 25°C water at a rate of 600 cm3/min. They exercised on an ergometer at 50% of their maximum work rate for 10 to 15 minutes until sweating commenced, and then remained continuously seated without exercise until their oxygen uptake increased. The rectal temperature and skin temperatures at four sites were monitored using thermistors. The sweating rate was measured at the forehead with a sweat rate monitor. Oxygen uptake was monitored with a gas analyzer. The subjects were exposed to red or blue light at 500 lx and 1000 lx in both summer and winter.

Results

The mean CIZs at 500 lx were 0.23 ± 0.16°C under red light and 0.20 ± 0.10°C under blue light in the summer, and 0.19 ± 0.20°C under red light and 0.26 ± 0.24°C under blue light in the winter. The CIZs at 1000 lx were 0.18 ± 0.14°C under red light and 0.15 ± 0.20°C under blue light in the summer, and 0.52 ± 0.18°C under red light and 0.71 ± 0.28°C under blue light in the winter. A significant difference (P <0.05) was observed in the CIZs between red and blue light at 1000 lx in the winter, and significant seasonal differences under red light (P <0.05) and blue light (P <0.01) were also observed at 1000 lx.

Conclusions

The present study demonstrated that dynamic changes in the physiological effects of colors of light on autonomic functions via the non-visual pathway may be associated with the temperature regulation system.  相似文献   
90.
摘要 目的:探讨彩色多普勒超声检查对胎儿颅内畸形筛查的应用价值,并进行染色体异常分析。方法:选择2016年2月至2019年5月本院收治的进行胎儿颅内畸形筛查的高危孕妇120例,所有孕妇都给予彩色多普勒二维超声与三维超声筛查,对超声筛查异常者进行染色体异常分析,记录预后情况。结果:在120例孕妇中,二维超声诊断为胎儿颅内畸形12例,三维超声诊断为13例(预后都确诊为胎儿颅内畸形)。染色体核型筛查检出胎儿颅内畸形12例,其中21-三体综合征8例,18-三体综合征3例,13-三体综合征1例。确诊为胎儿颅内畸形的孕妇超声NT值都显著高于非胎儿颅内畸形孕妇,差异都有统计学意义(P<0.05)。孕妇选择终止妊娠10例,选择继续妊娠3例,继续妊娠3例胎儿都最终死亡。结论:产前彩色多普勒超声结合染色体核型在胎儿颅内畸形筛查中具有很高的价值,两者可互相补充,共同发挥诊断与预后评估价值。  相似文献   
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