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排序方式: 共有770条查询结果,搜索用时 15 毫秒
101.
102.
Muzaffer Mustafa Harlıoğlu Muhammet Enis Yonar Ayşe Gül Harlıoğlu Serpil Mişe Yonar Ardavan Farhadi 《Journal Of Applied Aquaculture》2018,30(3):197-210
The effects of 17β-estradiol injection (10?7mol/crayfish) in adult female Astacus leptodactylus on the reproductive efficiency (i.e., pleopodal egg and stage 1 juvenile numbers) were investigated. In addition, hepatosomatic index, gonodosomatic index, and 17β-estradiol (E2) levels of crayfish ovary, hepatopancreas, and heamolymph before and after injections were also determined. Results showed that E2 injection to females enhances the reproductive efficiency of A.leptodctylus. E2 injection significantly increased pleopodal egg and stage 1 juvenile numbers, GSI, HSI, and concentrations of E2 in heamolymph, ovary, and hepatopancreas. However, E2 injection did not accelerate time of mating and proportion of pleopodal egg-berried females at the first week of reproduction season in this species. This study highlights that to improve the reproductive efficiency of A.leptodctylus by using hormones to regulate the ovarian cycle, E2 should be used at least 1.5 months before the commencement of the breeding season. 相似文献
103.
Body fluid medical wastes are infectious clinical wastes (blood, saliva, urine) due to their high pathogenic content. Incineration is the most commonly used method in waste management that possess high water content along with molecularly dissolved species such as proteins. The process is costly; so that the removal of solid content dissolved in aqueous part by preliminary filtration can reduce the volume of the waste material. In this study, fibrous mats were prepared by electrospinning of PS wastes from DMF and THF solutions. Then they are employed in the removal of protein-based solid contents of body fluid medical wastes before their disposal. Two sources of PS waste (CD cover and Styrofoam) were employed along with virgin PS for comparison. The adsorption capacity of as-prepared electrospun fibers was examined for three model proteins: Bovine Serum Albumin (BSA), Myoglobin (MYO), and Trypsin (TRY). The fibers obtained from PS CD wastes have remarkably larger protein sorption capacities (particularly BSA) than the fibers obtained from virgin PS. XPS reveals the presence of CaCO3 domains in CD covers added into PS during their production steps probably to increase mechanical properties. There may be an electrostatic interaction between Ca2+ and the negatively charged groups of the protein. In this way, PS wastes could be converted to a beneficial secondary product by electrospinning and also resulting materials promises for the disposal of body fluid medical wastes. This may be one of the frontiers study on the removal of medical wastes by adsorbents produced via electrospinning of waste polymers. 相似文献
104.
采用PEG预处理对辽星1号水稻幼苗进行干旱锻炼,研究其对盐胁迫下水稻幼苗根系的缓解作用。水稻幼苗培养1周后用10% PEG 6000预处理3 d,然后复水3 d,最后用100 mmol·L-1 NaCl胁迫处理3 d。测定水稻幼苗根系的相对含水量、根系活力、丙二醛含量及抗氧化酶(SOD、POD、CAT、APX)活性。结果表明,PEG预处理的水稻幼苗根系MDA含量显著低于盐胁迫的处理(P<005),而幼苗根系相对含水量、根系活力以及抗氧化酶活性则均高于盐胁迫处理。说明PEG预处理可以提高水稻幼苗根系的耐盐性,缓解水稻幼苗在盐胁迫下所受的部分伤害。 相似文献
105.
106.
This study was conducted under semi-arid conditions in ?anl?urfa province (Turkey) in 2010–2011. One orchard each of peach, apricot and nectarine was selected for the study. There was less than one mile distance separating the orchards, and therefore climate, soil and topography were similar. Adult emergence, population peaks, number of generations per year and damage of the peach twig borer [PTB] [Anarsia lineatella Zell. (Lepidoptera: Gelechiidae)] on twigs and fruits were determined. Sex pheromone traps were used to determine moth population dynamics. Fruits and twigs were checked to determine damage rate and host preference of the PTB among peach, apricot and nectarine. This study showed that the first adults of the PTB were detected in early May and pest populations peaked four times during both years. The highest numbers of adults captured by the pheromone traps in peach, apricot and nectarine orchards were 115, 86 and 70 adults/trap, respectively. The PTB damage rates on twigs were 38, 18 and 16% (2010) (P < 0.05) and 30, 22 and 14% (2011) (P < 0.05), while damage rates on fruits were 29, 6 and 6% (2010) (P < 0.05) and 14, 8 and 5% (2011) (P < 0.05) in peach, nectarine and apricot, respectively. The results showed that A. lineatella caused greater damage on peaches than on apricots and nectarines. 相似文献
107.
M Aksoy H Erdem F Hatipolu NC Lehimciolu O Akman K Özkan 《Reproduction in domestic animals》2009,44(1):156-160
This study was performed to describe a practical technique for ultrasound examination of the scrotal content of the rabbit. The scrotal content of normal rabbits and those with induced lesions (i.e. needle biopsy of the testis and epididymal ligation) were viewed using a portable scanner connected to a 5 or 7.5 MHz real time, B-mode linear array transducer. The effect of frequency (5 and 7.5 MHz), pad material placed under the testicle (rubber, plastic and carton) and the presence of a water sack between the probe and organ were examined to optimize the technique. The best image quality was obtained using a 5-MHz probe when the testicle was fixed on a rubber pad and covered by a water sack. Testicular parenchyma was imaged as homogeneous and moderately echoic. Caput and cauda epididymis were identified as homogeneous and less echoic compared with the testis parenchyma. Variations in the testicular echotexture that occur secondarily to epididymal ligation and testis biopsy could be screened readily. In conclusion, real-time ultrasonography, performed as described in this study, may provide a valuable tool to screen scrotal contents and to identify certain pathological conditions that affect fertility in the rabbit. 相似文献
108.
泡泡果的染色体核型分析 总被引:2,自引:0,他引:2
观察了泡泡果(Asim ina triloba(L.)Dunal)的染色体并进行了核型分析,结果表明:其核型公式为:2 n=2 x=16=14 sm(2 SAT) 2 st,第8对染色体上有1对明显大于短臂的大随体。按Stebb ins的核型分类标准,它属“3 B”型,较不对称,为较进化的类型。 相似文献
109.
Nano-TiO2 based multilayer nanocomposite films were fabricated on cationically modified woven cotton fabrics by layer-by-layer molecular
self-assembly technique. Cationization process was used to obtain cationic surface charge on cotton fabrics. Attenuated total
reflectance Fourier transform infrared spectroscopy analyses were used to verify the presence of cationic surface charge and
multilayer films deposited on the fabrics. Scanning electron microscope micrographs of poly(sodium 4-styrene sulfonate)/TiO2, nano polyurethane/TiO2, and TiO2/poly(diallyldimethylammonium chloride) multilayer films deposited on cotton fabrics were taken. With nano-TiO2 based multilayer film deposition, the protection of cotton fabrics against UV radiation is enhanced. The UV protection durability
of the self-assembled multilayer films deposited on the cotton fabrics was analyzed after 10 and 20 washing cycles at 40 °C
for 30 min. Air permeability and whiteness value analysis were performed on the untreated and multilayer film deposited cotton
fabrics. The effect of layer-by-layer deposition process on tensile strength properties of the warp and weft yarns was determined. 相似文献
110.
Erdoğan Atmiş H. Batuhan Günşen Banu Bayramoğlu Lise Wietze Lise 《Forest Policy and Economics》2009,11(2):102-108
This study analyses forest cooperative's participation in forestry in Turkey. The study was carried out with 71 forest cooperatives in the Kastamonu province, located in the Western Black Sea Region. By using a principal component analysis it was found that the most important factors affecting forest cooperative's participation in forestry are: (1) member involvement, (2) forest ownership and administration, and (3) harmony within cooperatives and between cooperatives and the state. These three factors explained 59% of participation within a cooperative.Regression analyses indicate that active members, sufficiency of work, use of published material, and the availability of capital and credit are important variables to explain variations in participation. A game theoretic model indicates a positive link between a cooperative's wood production (payoff) and levels of participation as derived from the principal component analysis, indicating that a productive forest goes hand in hand with high levels of forest cooperative's participation in forestry. 相似文献