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241.
Yin P Hariadi RF Sahu S Choi HM Park SH Labean TH Reif JH 《Science (New York, N.Y.)》2008,321(5890):824-826
Synthesizing molecular tubes with monodisperse, programmable circumferences is an important goal shared by nanotechnology, materials science, and supermolecular chemistry. We program molecular tube circumferences by specifying the complementarity relationships between modular domains in a 42-base single-stranded DNA motif. Single-step annealing results in the self-assembly of long tubes displaying monodisperse circumferences of 4, 5, 6, 7, 8, 10, or 20 DNA helices. 相似文献
242.
243.
GS Maciel RR Uscategui VT de Almeida MEF Oliveira MAR Feliciano WRR Vicente 《Reproduction in domestic animals》2014,49(4):701-704
The occurrence of the pyometra is most common in the first half of the dioestrus when there is decreased cellular immunity associated with increased serum concentration of progesterone in females. The aim of this study was to determine the immunological profile of bitches with pyometra, studying serum levels of IL‐2, IL‐4, IL‐10, IFN‐γ, KC‐like and TNF‐α and comparing them with those of healthy bitches in anoestrus, dioestrus and pregnant. Forty females were divided into four experimental groups: group 1 (G1): with pyometra (n = 10); group 2 (G2): bitches in the second week of gestation (n = 10); group 3 (G3): in anoestrus (n = 10); and group 4 (G4): in dioestrus (n = 10). The serum levels for IL‐2, KC‐like, INF‐γ and TNF‐α were similar for all experimental groups. The values obtained for IL‐10 were found increased (p < 0.001) in animals in dioestrus and pyometra compared with females in anoestrus and pregnant, and the levels of IL‐4 observed were significantly greater (p < 0.001) in bitches with pyometra when compared with others. The cytokine profile in animals with pyometra is similar to bitches in dioestrus for IL‐10 and had increase in IL‐4 for bitches with pyometra, which represents an anti‐inflammatory these cases. This suggests the presence of an immunosuppressive state in both cases, which may explain the propensity of bitches in dioestrus to be affected by pyometra and the severity of the disease on these animals. 相似文献
244.
245.
The purpose of this study is to offer acoustical database of warp knitted fabrics by investigating frictional sound properties
and physiological responses according to structural parameters such as construction, lap form, and direction of mutual guide
bar movement. Fabric sounds of seven warp knitted fabrics are recorded, and Zwicker’s psychoacoustic parameters — loudness(Z),
sharpness(Z), roughness(Z), and fluctuation strength(Z) — are calculated. Also, physiological responses evoked by frictional
sounds of warp knitted fabrics are measured such as electroencephalogram (EEG), the ratio of high frequency to low frequency
(HF/LF), respiration rate (RESP), skin conductance level (SCL), and photoplethysmograph (PPG). In case of constructions, frictional
sound of sharkskin having higher loudness(Z) and fluctuation strength(Z) increases RESP. By lap form, open lap has louder
and larger fluctuating sound than closed lap, but there aren’t significant difference of physiological responses between open
lap and closed lap. In direction of mutual guide bar movement, parallel direction evokes bigger changes of beta wave than
counter direction because of its loud, rough, and fluctuating sound. Fluctuation strength(Z) and roughness(Z) are defined
as important factors for predicting physiological responses in construction and mutual guide bar movement, respectively. 相似文献
246.
An estimated 43% of total blood volume was lost during craniectomy in a 32‐kg Labrador retriever. One episode of bradycardia, followed by ventricular tachycardia occurred during surgery when the rate of haemorrhage exceeded fluid replacement. Sinus rhythm was re‐established with intravenous lidocaine (1.25 mg kg?1). Twenty‐four hours later, premature ventricular complexes appeared followed by episodes of ventricular tachycardia, some requiring lidocaine treatment. Myocardial hypoxia resulting either from hypovolaemia and/or air embolism (the right transverse venous sinus was damaged during surgery) may have caused the arrhythmias. Mild intracranial hypertension may have aggravated the problem. 相似文献
247.
Selection of soybean mutant lines with altered seed coat colour and their antioxidant activity 下载免费PDF全文
Kyung Jun Lee Jin‐Baek Kim Hong‐Il Choi Bo‐Keun Ha Si‐Yong Kang Dong Sub Kim 《Plant Breeding》2015,134(5):573-579
In this study, the flavonoid and isoflavone contents in four checks with seed coat colour altered from yellow to black were determined, and their antioxidant activity was measured. Three anthocyanins (delphinidin‐3‐O‐β‐D‐glucoside, D3G; cyanidin‐3‐O‐β‐D‐glucoside, C3G; and petunidin‐3‐O‐β‐D‐glucoside, Pt3G) were detected in the four checks, while their controls (cvs. ‘Danbaek’ and ‘Daepung’) were not found. Among them, D‐16 derived from cv. ‘Danbaek’ showed the highest anthocyanin contents. The isoflavone contents of all checks showed lower levels compared to their controls. Among six isoflavones, glycitein was only detected in DP‐39. To analyse the radical scavenging activities among the four checks, we conducted DPPH, FRAP and UWLA assays. Significant differences in antioxidant activities were obtainable in the four checks, which contained significant differences in levels of anthocyanins and isoflavones. Based on these results, gamma irradiation may change the isoflavone and anthocyanin contents of soybean. Our four checks selected in this study may be useful for breeding soybean varieties to alter their nutritional values. 相似文献
248.
Conjugated linoleic acid isomers in partially hydrogenated soybean oil obtained during nonselective and selective hydrogenation processes 总被引:2,自引:0,他引:2
Partially hydrogenated soybean oil samples were collected during selective and nonselective hydrogenation processes. The formation of conjugated linoleic acids (CLAs) during hydrogenation was greatly dependent on the types and duration of hydrogenation processes. During hydrogenation processes, CLA contents increased initially. After reaching maximum CLA content, the content decreased during hydrogenation. Selective hydrogenation was much more favorable for the formation of conjugated linoleic acids. With nonselective hydrogenation process, the total CLA content was a maximum (9.06 mg total CLA/g oil) at 35 min. However, with the selective hydrogenation process, the total CLA content was a maximum (98.27 mg total CLA/g oil) at 210 min. The CLA contents in some of the tested selectively hydrogenated soybean oils were among the highest ever reported in foods. 相似文献
249.
AFLP profiles characteristic to Panax ginseng and Panax quinquefolius were generated using primers E-AGG/M-CAA. P. ginseng samples from different farms in China and Korea are homogeneous genetically [similarity index (SI) = 0.88-0.99], whereas samples of P. quinquefolius from different sources are much more heterogeneous (SI = 0.64-0.96). Detailed analysis of one of the polymorphic bands in P. ginseng led to the identification of a minisatellite Pg2, which contains eight repeats of 5'-AGGACTCATCACATTGTTACTC. The minisatellite DNA was consequently used in directed amplification minisatellite region DNA analysis to authenticate the two ginsengs. 相似文献
250.
姚汉清 《湖南农业大学学报(自然科学版)》1988,(4)
本文分析了轮式拖拉机导向轮定位参数对轮子的作用和各参数之间的关系,以便为改进、设计轮式拖拉机前轮定位提供科学依据。 相似文献