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211.
The effects of sex and age on patterns of circulating somatotropin (ST) concentration and plasma IGF-I, IGF-II, insulin, and IGF binding protein-3 (IGFBP-3) were studied in ram, wether, and ewe lambs (n = 7 or 8) sampled at mean ages of 81 (I1) and 158 d (I2). Between 81 and 158 d of age, rams grew more rapidly than wethers (P < .01), and wethers grew more rapidly than ewes (P < .01). The sex differences in growth were reflected in empty body weight at slaughter: rams > wethers > ewes (P < .05). Mean plasma ST concentrations, ST pulse amplitude, and integrated plasma ST concentrations were greater (P < .05) in rams than in ewes at I1 and I2. Characteristics of the ST plasma profile in wethers were generally intermediate between those of rams and ewes. The interpulse interval was greater in ewes than in wethers at I2. The IGF-I and IGFBP-3 concentrations were greater in rams than in ewes at both sampling times. Plasma IGF-II was greater in ewes than in rams at I2. Mean plasma ST was approximately two thirds less at I2 than at I1 regardless of sex. Mean plasma ST and IGF-I at both ages were positively correlated with growth. Mean plasma ST at I2 was negatively correlated with fatness at slaughter. Sex and age significantly affected patterns of circulating ST and concentrations of IGF-I and IGFBP-3 in prepubertal growing lambs, under conditions for which growth rates and composition were also sexually dimorphic.  相似文献   
212.
The effects of 1-hydroxyethylidene-1, 1-bisphosphonate (HEBP) and two Chinese traditional (Kampo) medicines, Dai-saiko-to and Saiko-ka-ryukotsu-borei-to on spontaneous soft tissue (heart and tongue) mineralization in DBA/2NCrj mice were studied. These agents were given orally for 4 weeks to DBA/2NCrj mice. After 2 weeks of administration in the heart, 0.006 and 0.03% (w/v) HEBP decreased calcium content by 90 and 30%, respectively, while 0.27 and 2.7 mg/ml Dai-saiko-to reduced calcium content by 30 and 45%, respectively. Saiko-ka-ryukotsu-borei-to (0.27 mg/ml) reduced both calcium and phosphorus content by 50 and 35%, respectively. However, their inhibitory effects on the heart were not observed after 4 weeks of administration. The compounds delayed the onset of increases of bulk calcium and phosphorus content. In the tongue, at 4 weeks, 0.006 and 0.03% (w/v) HEBP reduced calcium content by 30 and 45%, respectively, while two Kampo medicines (at both concentrations used) significantly reduced the content of calcium (by 27-79%) and phosphorus (by 24-32%). These results strongly suggest that two Kampo medicines as well as HEBP may be useful in preventing and curing soft tissue calcification.  相似文献   
213.
The relationship between endometriosis and infertility is observed frequently. Patients with both conditions require a conservative approach to their management. Since hormonal therapy is one of those approaches, we sought to compare the efficacy of Danazol and Gestrinone in 80 infertile patients (48 and 32, respectively). Therapy lasted 6 months in both treatment groups, and all patients studied had laboratory tests performed and were clinically evaluated and classified through laparoscopy before and after therapy. The improvement of symptoms and favorable follow-up were similar with both treatments. The reestablishment of menstrual patterns and fertility were also nearly alike in both groups. However, Gestrinone was associated with fewer secondary effects and is easier to administer than Danazol. We conclude that Gestrinone is a useful medication in the management of the infertile patient with endometriosis.  相似文献   
214.
本工作中我们选择了B2O3-La2O3-Y2O2-ZrO2系统作为玻璃基础组成。最后获得的LaK747/509玻璃组成中,不含有钍的成份。由于该玻璃具有一系列好的性质,如析晶范围窄、析晶速度慢以及粘度大等等,因此可以成功地在12-30L铂埚中进行熔制,并获得了尺寸为φ200×25mm的高质量玻璃。  相似文献   
215.
High-density structures with relatively well-ordered nanopore arrays have been obtained by the self-ordering growth of nanopores occurring during anodisation of aluminium in sulphuric acid. The resulting array of well-ordered nanopores strongly depends on an applied voltage of anodising, temperature and a procedure of synthesis. Regular arranged hexagonal arrays on aluminium with a relatively uniform pore diameter, interpore distance, and depth of pores exceeding 90 μm, can be formed by the self-ordering two-step anodising at 1 °C. The interpore distance and the pore diameter were evaluated on anodised aluminium layers obtained at different cell potentials ranging from 15 to 25 V. The detailed analyses of their uniformity were performed from SEM images. The analysis of a pore arrangement defects was made from SEM top view images taken on samples anodised at various cell potentials. The defect maps, known as Delaunay triangulations, of the arrangement of about 1000 pores were constructed for different applied anodising potentials. The percentage of pores that are not six-fold coordinated by the neighbouring pores indicates the percentage of defected surface.  相似文献   
216.
安全:爆破工程永恒的主题——2001年重大拆除爆破工程回顾   总被引:19,自引:10,他引:9  
冯叔瑜  顾毅成 《爆破》2002,19(1):1-4
通过对2001年我国重大拆除爆破工程的回顾,认为在提高大面积毫秒非电起爆网络可靠性,控制爆破震动、扬尘、噪声等环境影响,与机械清理配合,实现快速施工等方面取得了进展与突破;对几起爆破安全事故进行了初步分析.为保证拆除爆破工程安全,在加强理论研究、开展技术创新、建立科学有序的管理制度等方面提出了建议意见.  相似文献   
217.
The UV irradiation (lambda = 362 nm) of aflatoxin B1 (AfB1) dissolved in water resulted in the formation of an oxidized product. The process was not inhibited by ionol, a routine inhibitor of the radical processes. The oxidized product was not found in the system where AfB1 was metabolized by the 3-methylcholanthrene-activated rat liver microsomes. It is suggested that the product is identical with 2,3-dihydrodiol of AfB1.  相似文献   
218.
This study investigates the phenotype of turbulent (Re = 5,200) and laminar (Re = 2,000) flow-generated Pseudomonas fluorescens biofilms. Three P. fluorescens strains, the type strain ATCC 13525 and two strains isolated from an industrial processing plant, D3-348 and D3-350, were used throughout this study. The isolated strains were used to form single and binary biofilms. The biofilm physiology (metabolic activity, cellular density, mass, extracellular polymeric substances, structural characteristics and outer membrane proteins [OMP] expression) was compared. The results indicate that, for every situation, turbulent flow-generated biofilms were more active (p < 0.05), had more mass per cm(2) (p < 0.05), a higher cellular density (p < 0.05), distinct morphology, similar matrix proteins (p > 0.1) and identical (isolated strains -single and binary biofilms) and higher (type strain) matrix polysaccharides contents (p < 0.05) than laminar flow-generated biofilms. Flow-generated biofilms formed by the type strain revealed a considerably higher cellular density and amount of matrix polysaccharides than single and binary biofilms formed by the isolated strains (p < 0.05). Similar OMP expression was detected for the several single strains and for the binary situation, not dependent on the hydrodynamic conditions. Binary biofilms revealed an equal coexistence of the isolated strains with apparent neutral interactions. In summary, the biofilms formed by the type strain represent, apparently, the worst situation in a context of control. The results obtained clearly illustrate the importance of considering strain variation and hydrodynamics in biofilm development, and complement previous studies which have focused on physical aspects of structural and density differences.  相似文献   
219.
UV-LIGA深度光刻机平滑衍射技术研究   总被引:4,自引:0,他引:4  
UV-LIGA深度光刻技术是加工微型机电系统的一项重要的微细加工技术。介绍了一种平滑衍射效应的位错强度叠加原理,它采用了蝇眼积分透镜去平滑衍射,并模拟数值计算了硅片表面的光强分布,最后给出了光刻结果。  相似文献   
220.
Readers' eye movements were monitored as they read sentences containing noun-noun compounds that varied in frequency (e.g., elevator mechanic, mountain lion). The left constituent of the compound was either plausible or implausible as a head noun at the point at which it appeared, whereas the compound as a whole was always plausible. When the head noun analysis of the left constituent was implausible, reading times on this word were inflated, beginning with the first fixation. This finding is consistent with previous demonstrations of very rapid effects of plausibility on eye movements. Compound frequency did not modulate the plausibility effect, and all disruption was resolved by the time readers' eyes moved to the next word. These findings suggest (contra Kennison, 2005) that the parser initially analyzes a singular noun as a head instead of a modifier. In addition, the findings confirm that the very rapid effect of plausibility on eye movements is not due to strategic factors, because in the present experiment, unlike in previous demonstrations, this effect appeared in sentences that were globally plausible. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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