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A. BELÉIA S.H. PRUDENCIO-FERREIRA F. YAMASHITA T.M. SAKAMOTO L. ITO 《Journal of texture studies》2004,35(5):542-553
Two cassava varieties, at three harvesting ages, 6, 12 and 24 months, were analyzed for sensory flavor and texture development. Maximum shear force, Texture Profile Analysis (TPA) and water absorption during cooking were determined at various sampling times. Changes during cooking were described by pseudo‐zero order models for water absorption, flavor and texture development for the fast cooking samples. The 24‐month‐old roots had higher variability and never reached optimum texture or flavor development. Significant pseudo first order models could represent hardness, cohesiveness and chewiness of the TPA, while springiness and adhesiveness varied in a non‐linear fashion. Maximum shear force was 111 N for raw samples and 8.1 N for samples that cooked in less than 25 min. Samples that required longer cook time had on the average a maximum shear force of 19 N. 相似文献
54.
The hypothalamo-pituitary-adrenal (HPA) axis is modulated by sex hormones. Few data exist on the relation between acute estrogen deficit and HPA axis response to corticotropin-releasing hormone (CRH). The effects of a sudden drop in estradiol levels on basal and CRH-stimulated levels of ACTH, cortisol, testosterone, androstenedione and 17-hydroxyprogesterone (17-OHP) were assessed in nine premenopausal women (44-48 years of age), before and after ovariectomy. The CRH test was performed before and 8 days after ovariectomy. A significant reduction in ACTH and adrenal steroids but not in cortisol response to CRH was observed after ovariectomy. The ratio of deltamax androstenedione/17-OHP after CRH stimulation was substantially the same before and after ovariectomy, whereas deltamax 17-OHP/cortisol was significantly lower in ovariectomized women showing increased 21- and 11beta-hydroxylase activity. The results show that the acute estrogen deficit induces changes in the HPA axis characterized by reduced stimulated secretion of ACTH and steroids but normal stimulated cortisol production. 相似文献
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II Kalachev AN Baídus' OA Ivanova EA Ganina IA Boldyrev EA Svetoch 《Canadian Metallurgical Quarterly》1997,(6):32-37
Unlike the glanders agent, the superficial structures of the melioidosis agent were demonstrated to be responsible for marked was immunosuppressive activity. Some antigenic fractions suppressing the blast transformation of lymphocytes, reducing the count of T helpers and profoundly potentiating the infection in vivo were isolated from P. pseudomallei cells. The immunogenic and immunosuppressive activities of both agents' superficial structures were studied by high performance chromatography. Antigenic complexes that were able to protect immunized laboratory animals against fatal infections and to prevent bacterial carriage due to the activation of T cells and to the bacterial activity of macrophages were identified. A composition comprising several immunogens was found to provide an additive protective action against both causative agents. Therefore, the composition may be considered to be a prototype of a molecular antipseudomonadic vaccine. 相似文献
56.
本文研究了30w—CuEFP药型罩的制备及成形性能。研究采用了普通钨粉、铜粉和超细钨铜复合粉制备两种不同的棒材,然后测试棒材的锻造性能,最后选用普通钨铜材料制备EFP药型罩。结果表明,采用普通钨粉、铜粉刺备的材料具有较好的压力加工性能。制备的30W—CuEFP药型罩的材料的致密度达98%理论密度,退火后材料的抗拉强度达到320MPa,延伸率达17%。 相似文献
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IA Schepetkin 《Canadian Metallurgical Quarterly》1999,64(1):25-32
In various genetic disorders it has been observed that the severity of illness increases and the age at onset decreases in successive generations. This phenomenon is termed anticipation. We sampled 15 families, totalling 123 individuals with at least one person affected by a disease of the schizophrenia spectrum in the index generation in each family (IG; n = 33 affected out of a total of 67 individuals) and in the parental generation (PG; n = 16 affected out of a total of 56 individuals). The pedigrees had originally been identified for linkage studies in schizophrenia. We found a significant difference between IG and PG regarding severity of illness as defined by Kendler et al's hierarchical model of categories of the schizophrenia spectrum (p = 0.001). Age at onset was significantly earlier in the IG (21.6 +/- 6.6 years) than in the PG (40.2 +/- 9.2 years) (p = 0.0001). We excluded a potential birth cohort effect by investigating a control sample consisting of two non-overlapping birth cohorts of patients with schizophrenia. Age at onset between the two groups of the control sample did not differ. Anticipation is an important aspect in the investigation of a possible genetic basis, at least for the familial form of schizophrenia. Active research on a molecular level with special emphasis on trinucleotide repeats might be able to shed further light on this phenomenon. 相似文献
59.
The inhibition of arylamine N-acetyltransferase (NAT) activity by ibuprofen was determined in a human colon tumour (adenocarcinoma) cell line. Two assay systems were employed, one with cellular cytosols (9000 g supernatant) and the other with intact colon tumour cell suspensions. The NAT activity in a human colon tumour cell line was inhibited by ibuprofen in a dose-dependent manner in both systems, i.e. the greater the concentration of ibuprofen in the reaction, the greater the inhibition of NAT activities in both systems. The data also indicated that ibuprofen decreases the apparent Km and Vmax of NAT enzyme from human colon tumour cells in both systems examined. This report is the first demonstration to show that ibuprofen affects human colon tumour cell NAT activity. 相似文献
60.
HA Kazakova NS Entelis RP Martin IA Tarassov 《Canadian Metallurgical Quarterly》1999,442(2-3):193-197
The effect of quinine, a cinchona alkaloid, was studied on gastrointestinal transit in mice. Intraperitoneal (i.p.) administration of quinine inhibited the intestinal propulsion of a charcoal suspension at a dose of 100 mg/kg, comparing favorably with 5 mg/kg morphine. In an attempt to probe into the mechanism underlying this inhibition, a possible modulation by minoxidil (1 mg/kg, p.o.) and glibenclamide (1 mg/kg, p.o.), the drugs that, respectively, open and close ATP-sensitive K+ channels was tested on gastrointestinal transit in animals treated or not with quinine or morphine. While minoxidil produced no significant change of normal transit, glibenclamide significantly increased it. However, both drugs blocked the quinine-induced reduction in gastrointestinal transit. In contrast, the inhibitory effect of morphine on gastrointestinal transit was not modified by either drug. The effects of quinine as well as of morphine on gastrointestinal transit were significantly antagonized by naloxone (2 mg/kg, s.c.), a mu-opioid receptor antagonist but not by yohimbine (1 mg/kg, i.p.), an alpha2-adrenoceptor antagonist. Furthermore, quinine at a lower dose (25 mg/kg) that showed no per se effect on gastrointestinal transit, significantly potentiated the response to 2.5 mg/kg morphine. Although the role of ATP-sensitive K+ channels in the action of quinine and morphine was not clarified by the present results, a possible involvement of endogenous opioid(s) in the quinine-induced inhibition of gastrointestinal transit can be suggested. 相似文献