油梨果贮藏生理简介   总被引：2，自引：0，他引：2  

董建华 《热带作物科技》1996,(4):17-19,16

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美国核果类果树线虫的治理策略     

Nycz.  AP 王锡锋 《国外农学:植物保护》1992,5(2):25-27

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What is your diagnosis? Bronchial foreign body     

Volta A  Piccionello AP  Bonazzi M  Gnudi G  Bertoni G;American College of Veterinary Radiology 《Journal of the American Veterinary Medical Association》2007,230(2):191-192

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Oviposition responses of culex pipiens to a synthetic racemic Culex quinquefasciatus oviposition aggregation pheromone     

Michaelakis A  Mihou AP  Couladouros EA  Zounos AK  Koliopoulos G 《Journal of agricultural and food chemistry》2005,53(13):5225-5229

The oviposition pheromone of Culex quinquefasciatus was synthesized in a racemic form in a simple (five steps), efficient, high yielding (45% total yield), and low cost way (use of relatively low cost reagents). Our synthetic racemic pheromone (SRP) was tested in the laboratory for its bioactivity on Culex pipiens biotype molestus, which is a member of the species complex that Culex quinquefasciatusbelongs. In the testing conditions, bioactivity at the doses of 0.01, 0.1, 1, and 10 microg per cage was found with the best bioactivity achieved at 1 mug per cage. The effectiveness of our SRP offers a capable tool for improving mosquito oviposition traps for surveillance or even control programs.  相似文献   

Essential oils from plants and in vitro shoots of Hypericum androsaemum L     

Guedes AP  Amorim LR  Vicente AM  Ramos G  Fernandes-Ferreira M 《Journal of agricultural and food chemistry》2003,51(5):1399-1404

The essential oil yields obtained by hydrodistillation of the aerial parts of Hypericum androsaemum cultivated plants varied from 0.94 to 4.09 mg/g of biomass dry weight, depending of the harvest time. The respective analyses performed by gas chromatography and gas chromatography-mass spectrometry revealed more than 80 compounds, 72 of which were identified. Most of the compounds were sesquiterpene hydrocarbons, which, depending of the harvest time, corresponded to 43-78% of the total essential oil. The other compounds were distributed as monoterpene hydrocarbons, oxygen-containing sesquiterpenes, n-alkanes, 1-alkenes, and oxygen-containing monoterpenes, these being a minor group. In H. androsaemum in vitro shoots, sesquiterpene hydrocarbons represented >80% of the respective essential oil. Differences in the essential oil composition were found depending on the harvest time and origin, in vivo versus in vitro, of the plant material. The essential oil sampled in November was characterized by the highest levels of sesquiterpene hydrocarbons and a high number of n-alkanes and 1-alkenes, from C(18) to C(28), whereas that sampled in June of the following year showed the highest levels of n-nonane and 1-octene as well as monoterpene hydrocarbons, the second most representative group.  相似文献   

Sorption and vapor transmission properties of uncompressed and compressed microcellular starch foam     

Glenn GM  Klamczynski AP  Takeoka G  Orts WJ  Wood D  Widmaier R 《Journal of agricultural and food chemistry》2002,50(24):7100-7104

Microcellular starch foams (MCFs) are made by a solvent-exchange process and consist of a porous matrix with pores generally ranging from approximately 2 microm to submicrometer size. MCF may potentially be useful as a slow-release agent for volatile compounds because of its ability to sorb chemicals from the atmosphere and to absorb liquids into its porous structure, and because it can be compressed to form a starch plastic. MCF made of high-amylose corn and wheat starches was prepared with or without 2% (w/w) silicone oil (SO) or palmitic acid (PA). The MCF was loaded with 1% of various volatile compounds with vapor pressures ranging from 0.02 to 28 mm. The MCF depressed the vapor pressure from 0.37 to 37% compared to a control containing no MCF. Incorporating SO or PA in the matrix of the MCF had little effect on sorption of volatiles. Compressing MCF at 1.4, 6.9, and 69 MPa made a starch plastic with varying porosity. The vapor transmission rate of various volatile compounds through MCF was positively correlated to the vapor pressure of the test compound but was inversely proportional to the compression force used to form the starch plastic. The results indicate that uncompressed and compressed MCFs could be effective slow-release agents for a variety of volatile compounds, especially if used together.  相似文献   

BIOLOGICAL ABSTRACTS     

Osborn H  Hitchens AP  Hooker DR  Kofoid CA  Lewis IF  Ball ED  McClung CE  Schramm JR  Woods AF  Greenman MJ 《Science (New York, N.Y.)》1924,60(1561):485-489

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Porous, crystalline, covalent organic frameworks     

Côté AP  Benin AI  Ockwig NW  O'Keeffe M  Matzger AJ  Yaghi OM 《Science (New York, N.Y.)》2005,310(5751):1166-1170

Covalent organic frameworks (COFs) have been designed and successfully synthesized by condensation reactions of phenyl diboronic acid {C6H4[B(OH)2]2} and hexahydroxytriphenylene [C18H6(OH)6]. Powder x-ray diffraction studies of the highly crystalline products (C3H2BO)6.(C9H12)1 (COF-1) and C9H4BO2 (COF-5) revealed expanded porous graphitic layers that are either staggered (COF-1, P6(3)/mmc) or eclipsed (COF-5, P6/mmm). Their crystal structures are entirely held by strong bonds between B, C, and O atoms to form rigid porous architectures with pore sizes ranging from 7 to 27 angstroms. COF-1 and COF-5 exhibit high thermal stability (to temperatures up to 500 degrees to 600 degrees C), permanent porosity, and high surface areas (711 and 1590 square meters per gram, respectively).  相似文献   

Structure of West Antarctica     

Bentley CR  Crary AP  Ostenso NA  Thiel EC 《Science (New York, N.Y.)》1960,131(3394):131-136

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Loss of IGF2 imprinting: a potential marker of colorectal cancer risk   总被引：1，自引：0，他引：1  

Cui H  Cruz-Correa M  Giardiello FM  Hutcheon DF  Kafonek DR  Brandenburg S  Wu Y  He X  Powe NR  Feinberg AP 《Science (New York, N.Y.)》2003,299(5613):1753-1755

Loss of imprinting (LOI), an epigenetic alteration affecting the insulin-like growth factor II gene (IGF2), is found in normal colonic mucosa of about 30% of colorectal cancer (CRC) patients, but it is found in only 10% of healthy individuals. In a pilot study to investigate the utility of LOI as a marker of CRC risk, we evaluated 172 patients at a colonoscopy clinic. The adjusted odds ratio for LOI in lymphocytes was 5.15 for patients with a positive family history [95% confidence interval (95% CI), 1.70 to 16.96; probability P = 0.002], 3.46 for patients with adenomas (95% CI, 1.14 to 11.37; P = 0.026), and 21.7 for patients with CRC (95% CI, 3.48 to 153.6; P = 0.0005). LOI can be assayed with a DNA-based blood test, and it may be a valuable predictive marker of an individual's risk for CRC.  相似文献