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11.
To overcome the high energy-consuming process of microalgae drying, a two-step lipase catalysis technique for the preparation of biodiesel from microalgae lipid of Chlorella spp. was developed. In the first step, free fatty acids (FAAs) and triacylglycerols (TAGs) are released after cell disruption and extracted, while the TAGs were hydrolysed by free lipase in aqueous phase. In the second step, FAAs were esterified with ethanol in the catalysis of free suspended lipase. The maximum rate of hydrolysis and esterification was 93.6% and 91.3%, respectively. The effects of reaction parameters, such as reaction time, enzyme amount, water content and molar ratio of lipid to ethanol on hydrolysis or esterification, were investigated. The results indicated that two-step reaction process (hydrolyse esterify) for biodiesel production were feasible. 相似文献
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15.
Anti-histone antibodies in idiopathic and drug-induced lupus recognize distinct intrahistone regions 总被引:11,自引:0,他引:11
J P Portanova R E Arndt E M Tan B L Kotzin 《Journal of immunology (Baltimore, Md. : 1950)》1987,138(2):446-451
We have identified regions within core histones that are antigenic for autoantibodies in systemic lupus erythematosus (SLE) and drug-induced lupus. An immunoblotting technique was used to determine the reactivity of lupus antibodies for intact histones and for trypsin-resistant histone fragments that lack the amino- and carboxyl-terminal amino acids that are normally exposed in native nucleosomes. In SLE, the predominant anti-histone response was restricted to epitopes in the trypsin-sensitive regions. Of 20 SLE sera that had strong antibody activity for multiple intact histones, 17 showed minimal activity with any of the corresponding trypsin-resistant fragments. A markedly different pattern of reactivity was present in sera of patients with procainamide (Pr)-induced lupus in which antibodies to H2A, H2B, and the H2A-H2B complex had strong fragment activity. Interestingly, recognition of trypsin-resistant fragments was also noted in a small number of SLE sera that contained antibodies to the H2A-H2B complex. In contrast to both SLE and Pr-induced lupus, antibodies induced by hydralazine (Hy) reacted primarily with H3 and H4. Furthermore, these antibodies bound equally well to the corresponding trypsin-resistant regions that are thought to be relatively unexposed in native nucleosomes. Thus, the specificities of anti-histone antibodies in SLE, Pr-induced lupus, and Hy-induced lupus are markedly different, but in each disease reactivity appears to be restricted to a limited number of histone determinants. The data raise the possibility that autoantigen in the form of native nucleosomes may be recognized in SLE and possibly in Pr-induced lupus. In contrast, the propensity of Hy to induce autoantibodies to determinants usually not recognized in SLE or Pr-induced lupus may suggest a different immunogenic stimulus in this disease. 相似文献
16.
10 new Turkish taxa are described:Arenaria eliasiana, A. sivasica, A. monscragus, A. angustifolioides; Campanula lycica; Scutellaria orientalis subsp.tortumensis; Stachys choruhensis, S. tundjeliensis; Calamintha caroli-henricana; Aristolochia rechingeriana, the latter two species named in honour ofKarl Heinz Rechinger;Allium vuralii.
Dedicated to Prof. DrKarl Heinz Rechinger on the occasion of his 80th birthday. For part I see Pl. Syst. Evol.154, 111–128. 相似文献
17.
Mei-Lie M. C. Tan Ellen M. Rietveld Gijsbert A. M. van Marrewijk Ad J. Kool 《Plant cell reports》1987,6(3):172-175
Conditions were established for efficient plant regeneration from four freshmarket cultivars of Lycopersicon esculentum. In order to increase the yield of viable protoplasts which are able to sustain cell divisions, the donor plants are preconditioned by incubation at 25°C in the dark for 18 hours, followed by a cold treatment at 4°C in the dark for the last 6 hours, prior to protoplast isolation. Browning of the dividing cell colonies can be prevented by culturing protoplasts in 100 l droplets of low-melting agarose, surrounded by liquid medium. Alternatively, protoplasts can be cultured in liquid medium. In both procedures the plating efficiencies and percentage of shoot regeneration are increased, only when dilutions were performed with auxin-free culture medium. Shoot regeneration is obtained by using a two step procedure: initiation of greening of microcalli on a medium containing 0.2 M mannitol and 7.3 mM sucrose, which is followed by shoot development on a mannitol-free medium containing 0.5 M sucrose. In this way, plants can be regenerated within 3 months from the hybrid cultivars Bellina, Abunda, Sonatine and also from the true seedline Moneymaker. The latter one showed the highest regeneration frequency (30%).Abbreviations BAP
6-Benzylamino purine
- 2,4-D
2,4-dichlorophenoxy acetic acid
- IAA
indole acetic acid
- MES
2-(N-morpholino)- ethane sulfonic acid
- NAA
naphthalene acetic acid
- PE
plating efficiency 相似文献
18.
J J Coleman K C Tan J M Searles T R Hester F Nahai 《Plastic and reconstructive surgery》1989,84(4):589-95; discussion 596-8
Review of 101 patients who underwent 111 free jejunal autografts has demonstrated an absolute procedural failure rate of 13.5 percent. Salvage reconstruction with a second jejunum was successful in six of nine patients and one third-time jejunum was successful, giving an overall salvage rate of 70 percent. There were 33 patients experiencing pharyngocutaneous fistulas, 20 of whom had been previously irradiated. Of these patients, 15 experienced spontaneous closure and 9 others had successful surgical correction. The mortality rate was 5 percent. Eighty-three percent of patients were restored to adequate per oral alimentation. The jejunum, despite its relatively high complication rate, is an excellent method for pharyngoesophageal reconstruction, expeditiously providing return to function for patients with late-stage disease. 相似文献
19.
To determine whether a diurnal rhythm exists in neonates admitted to neonatal intensive care units where there is continuous artificial lighting and periodic nursing and medical care, plasma cortisol, adrenocorticotropin (ACTH), and beta-endorphin concentrations were measured in two groups of infants and in adult human volunteers. As expected, a diurnal rhythm was seen in adults. A diurnal rhythm was also found for cortisol and endorphin levels in neonates (3 to 4 days postnatally) with minimal stress and in infants who were clinically severely stressed. There was not a significant difference between the morning and afternoon concentrations of ACTH in these infants, but the afternoon concentrations were lower than the morning''s, as would be expected. We found that a diurnal rhythm does exist in neonates within the first few days of postnatal life and that the continuous lighting and medical and nursing interventions do not interfere with this rhythm. 相似文献
20.
Benito C. Tan 《Brittonia》1989,41(1):41-43
A review of the nomenclatural history ofThamnobryum subserratum andThamnobryum subseriatum shows that the former, which ranges widely from the Himalayas to Southeast Asia, has been misrepresented in the literature asThamnobryum “subseriatum,” and that the latter, which appears to be a Japanese endemic, has been called a superfluous name,Thamnobryum sandei. A new combination,Thamnobryum subseriatum (Mitt. ex Sande Lac.) Tan, is proposed for the Japanese endemic and its lectotype hereby designated. In addition, morphological differences between the two taxa are discussed. 相似文献