Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.

Input: Consider Input: Abstract: In order to perform quantitative in vitro and clinical studies on the removal of Al by the combined therapy of DFO administration and HD, an HPLC system for measuring DFO was established and a leaky membrane with enhanced permeability to middle molecular substances was developed. The DFO infusion caused rises in plasma Al levels (regarded as indicating the elution of accumulated Al) in patients undergoing HD. Plasma levels increased most in long-term patients and those with bone pain. Examination of Al clearances demonstrated that this increased plasma Al content passed through HD membranes at levels of more than 80 micrograms/l, and that the leaky membrane was more effective for removal of Al as well as DFO than the conventional one. Although a 1:1 complex between DFO and Al in an aqueous solution was confirmed, the formation of Al-rich complexes in vivo was suggested. It is concluded that Al-DFO complex formed in vivo can be effectively removed across the leaky membrane.

Output: Aluminum

Input: Consider Input: Abstract: We have developed a variable suction system for irrigation, aspiration and vitrectomy. The system is regulated by the operator's finger-tip.

Output: Equipment Design

Input: Consider Input: Abstract: The free primary amines present in the faeces of 44 infants (1-18 months) with gastroenteritis have been examined by field desorption mass spectrometry of the lactone form of their fluorescamine derivatives without their prior separation. p-Tyramine, 2-phenylethylamine, the diamines, putrescine and cadaverine and several of their acyl derivatives were common constituents, but a number of other amines were also characterised. Using thin layer chromatography and field desorption mass spectrometry of the amine dansyl derivatives a comparative study was made of the faecal amines of 13 selected infants with gastroenteritis (diarrhoea) and of 13 healthy infants. p-Tyramine, the most abundant amine, was significantly higher (p = 0.02) in the sick infants. The overall presence of p-tyramine was more significantly related to the diet of the infants. Faecal tyramine was low in breast fed infants but significantly higher (p = 0.01) in infants fed cow's milk.
Output: Amines