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1.
Eight samples of cashew nut oil were assayed, and the component triacylglycerols, fatty acids and several unsaponifiable compounds were analyzed by gas chromatography (GC) and high-performance liquid chromatography (HPLC). Total lipid amount, unsaponifiable percentage, fatty acids, sterols, triterpene alcohols and tocopherols are reported here. The combination of GC and HPLC enhanced the resolution of compound classes.  相似文献   
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The growing popularity of the information superhighway has opened up exciting opportunities for companies looking to, not only maintain their current customer base, but also to reach new customers. One of the most popular methods to enter into cybermarketing has been to establish a home page or Web site on the Internet. Almost two-thirds of Fortune 500 companies currently maintain home pages on the Web. An analysis of the content of corporate home pages provides useful insights. Over four-fifths of the companies display products and services (93.2%) and company overview (86.1%) information. Roughly three-fourths of the companies present interactive feedback (79.3%) and what's new (71.1%). Less than one-third (26.2%) of Fortune 500 companies provide for online business. An analysis of the data also provides valuable insight into the future trends of home page usage by large business organizations.  相似文献   
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A rapid procedure has been developed for the isolation of methyl esters of trans-monoenoic fatty acids by silver ion high-performance liquid chromatography. The combined saturated plus trans-monoene fraction was collected for analysis by gas chromatography and comparison with the composition of the unfractionated sample. The trans-monoene contents of partially hydrogenated vegetable oils, determined in this way, are compared with data obtained by Fourier-transform infrared spectroscopy. Alternative methods of base-line correction are discussed. The infrared technique gave values that were a little higher than the chromatographic ones, presumably because the former also detected trans unsaturation in di- and polyunsaturated fatty acids.  相似文献   
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1 W fibre coupled power InGaAsP/InP 14xx pump laser for Raman amplification   总被引:1,自引:0,他引:1  
A 1 W record singlemode fibre coupled output power using 1460 nm InGaAsP/InP non-tapered buried ridge lasers has been demonstrated. The impact of the bandgap of the passive quaternary waveguide on internal loss was investigated. Optimised design allows internal losses as low as 3.3 cm/sup -1/, external efficiency of 0.46 W/A for a 3 mm-long laser and symmetrical (12/spl deg//spl times/12/spl deg/) far-field pattern.  相似文献   
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As part of a program to study the chemical composition of algal biomasses, the composition of the unsaponifiable matter of the lipids of ten algal species (fiveMyxophyceae and fiveChlorophyceae) was investigated. The total unsaponifiable content, its general composition, and the components of the hydrocarbon fraction are discussed in the present paper. The unsaponifiable content of green algae is constantly higher than that of the blue-green ones, with the exception ofChlorella. In both algal classes, the major components are hydrocarbons and sterols. Blue-green algae are richer in hydrocarbons, whereas the green ones contain higher amounts of sterols. In most of the species examined, at least 48 components are present in the hydrocarbon fraction. Each algal species shows a characteristic gas liquid chromatography pattern, but n-C17 is always one of the most abundant components. Generally, the prokaryotic blue-green algae show a simpler hydrocarbon composition than the eucaryotic green algae, which contain higher amounts of high mol wt components. Unsaturated hydrocarbons are generally present in very limited quantities, with the exception ofSpirulina sp. andChlorella, sp., which contain a C17 alkene. Green algae also contain appreciable amounts of a C27 monoene and of squalene.  相似文献   
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This paper aims at describing the neuroendocrine cell growths of the gastric mucosa and their pathogenesis. In the corpus-fundus mucosa, gastric neuroendocrine nontumor growths are mostly represented by hyperplastic and, more rarely, dysplastic enterochromaffin-like (ECL) cell changes, while hyperplasia of gastrin-producing (G) cells and, rarely, of somatostatin-producing (D) cells are reported in the antral mucosa. The large majority of gastric neuroendocrine tumors is made by benign, gastrin-dependent, well-differentiated ECL cell growths arising in a background of chronic atrophic gastritis (type I) or, more rarely, associated with type I multiple endocrine neoplasia (MEN I) and Zollinger-Ellison (ZE) syndromes (type II). Rare, aggressive, frequently metastatic, well-differentiated gastric neuroendocrine tumors are gastrin-independent and arise as sporadic lesions in the absence of specific gastric pathology (type III). Poorly differentiated neuroendocrine carcinomas (PDEC) are rare, highly aggressive carcinomas. A central role for gastrin is postulated in the pathogenesis of well-differentiated type I and II ECL cell tumors with different possible genetic mechanisms. A more complex genetic background, independent of gastrin and possibly implicating altered function or mutation of p53 and other genes is highly suspected for the development of aggressive type III ECL cell carcinomas and PDECs.  相似文献   
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Cancer of the papilla (ampulla) of Vater is an uncommon disease that kills 60% of affected patients. There is general agreement that local spread of the tumor (T stage) is the only significant and independent prognostic factor for this cancer, whereas the predictive value of tumor grade and lymph node metastases is controversial. The genetic anomalies involved in this process have the potential to serve as additional prognostic markers. We explored 25 ampullary cancers for the occurrence of instability at simple repeat DNA sequences (microsatellites) of the type seen in replication error phenotype (RER-positive) cancers. Ten microsatellites from five different chromosomes were amplified by PCR from both normal and cancer tissue DNA of the same patients. A tumor was defined as RER-positive when microsatellite instability was found in the majority (>/=6) of the loci analyzed. Five cancers (20%) showed a RER phenotype and were associated with long survival of patients (32-96 months), whereas RER-negative cancers had a significantly poorer prognosis (Mantel-Cox test; P = 0.0084), with a median actuarial survival of 17 months. We also report that three (12%) patients belonged to cancer-prone families and four (16%) were cancer-prone individuals.  相似文献   
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