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961.
采用生物化学方法的方法,对大鳍鱯繁殖期的性腺、肝脏、肌肉的氨基酸和脂肪酸进行测定.结果表明:大鳍鱯雄性亲鱼精巢、肝脏和肌肉中,肌肉中氨基酸总量最高,为40.90g/100g;其次是精巢,为26.38g/100g;肝脏中含量最低,为18.38g/100g。从必需氨基酸占总氨基酸的比例来看,精巢最高,占53.41%;其次是肌肉,占52.93%;肝脏中最低,占51.96%。雌性亲鱼肌肉中氨基酸总量最高,为40.61g/100g;其次是卵巢,为22.42g/100g;肝脏中含量最低,为17.04g/100g。从必需氨基酸占总氨基酸的比例来看,卵巢最高,占52.85%;其次是肝脏,占51.76%;肌肉中最低,占49.OO%。从脂肪酸组成来看,雌雄亲鱼均为MUFA所占比例最高,其次是SFA,PUFA比例最小。雄鱼与雌鱼的三种组织器官中,所占比例较高的脂肪酸相似,它们是C18:1n.9(油酸)、C16:0(软脂酸)、C18:2n-6(亚油酸)和C16:1n-7(棕榈酸)。研究揭示了大鳍鱯繁殖期雌、雄亲鱼主要组织器官在物质构成上的特性。 相似文献
962.
雷志平 《西安体育学院学报》1992,(3)
本文通过对女子柔道运动员比赛、训练中血乳酸、血糖及血尿素氮等生化指标的测试结果,分析探讨女子柔道运动供能代谢特点及运动训练的一般生化原则。旨在对制定训练计划及掌握运动量提供理论依据。 相似文献
963.
醋酸/水分离研究进展 总被引:8,自引:0,他引:8
醋酸是一种重要的化工原料,其水溶液广泛存在于各类工业过程中,由于醋酸/水体系的相对挥发度不大,生产中用于分离醋酸/水的普通精馏和共沸精馏工艺能耗较高,因此研究者和工业界都在寻求更好的分离方法,目前醋酸/水的分离方法有精馏法、萃取法、醋化法、中和法、吸附法、膜分离法等,其中有些方法已经工业化,具有成熟的生产工艺;有些则处于研究阶段,本文对这些方法的研究现状及应用前景进行了介绍和评述,提出了萃取精馏法将是一很有前途的分离方法。 相似文献
964.
对α-亚麻酸及其乙酯分别在氧气气氛和氮气气氛下进行一定剂量的γ-辐射,每隔两天测定其过氧化值。研究结果表明:辐射剂量和时间对亚麻酸的过氧化值有较大影响,本文同时探讨了亚麻酸在γ-辐射下过氧化值与反应机制之间的内在联系。 相似文献
965.
Miriam Varkey R. Sundara Devi Shrinivas B. Rao 《Indian journal of clinical biochemistry : IJCB》1997,12(1):63-66
The levels of total sialic acid, lipid bound sialic acid and fucose were estimated in the sera of patients with benign and
malignant tumours of breast. An increase was noted in all the three parameters, with a more marked increase in malignancy,
when compared with benign and controls. Consequent to surgery, there was an elevation in the serum levels of the above parameters
than the values prior to surgery and a decline was noted two months after surgery although none of the values reached the
normal range. These results suggest a close association of the glycoproteins with the tumour burden and further signify their
role in early detection and staging of cancer breast. 相似文献
966.
967.
968.
Trevino L Contreras-Esquivel JC Rodríguez-Herrera R Aguilar CN 《Journal of Zhejiang University. Science. B》2007,8(10):771-776
The influence of the physical structure of polyurethane matrix as a support in a solid state culture in tannase production
and gallic acid accumulation by Aspergillus niger Aa-20 was evaluated. Three different polyurethane matrices were used as the support: continuous, semi-discontinuous and discontinuous.
The highest tannase production at 2479.59 U/L during the first 12 h of culture was obtained using the discontinuous matrix.
The gallic acid was accumulated at 7.64 g/L at the discontinuous matrix. The results show that the discontinuous matrix of
polyurethane is better for tannase production and gallic acid accumulation in a solid state culture bioprocess than the continuous
and semi-discontinuous matrices.
Project supported by the Agricultural, Livestock and Fishing Department (SAGARPA, No. 12385) and the National Forest Commission
(CONAFOR, No. 2004-C01-13), and the Council of Science and Technology, Mexico 相似文献
969.
Guo R Li SB Zhao LN Zhao YS Lu W Yuan P Deng P Liao F 《Journal of Zhejiang University. Science. B》2007,8(12):867-874
There was a slow-relaxing tail of skeletal muscles in vitro upon the inhibition of Ca^2+-pump by cyclopiazonic acid (CPA). Herein, a new linearly-combined bi-exponential model to resolve this slow-relaxing tail from the fast-relaxing phase was investigated for kinetic analysis of the isometric relaxation process of Bufo gastrocnemius in vitro, in comparison to the single exponential model and the classical bi-exponential model. During repetitive stimulations at a 2-s interval by square pulses of a 2-ms duration at 12 V direct currency (DC), the isometric tension of Bufo gastrocnemius was recorded at 100 Hz. The relaxation curve with tensions falling from 90% of the peak to the 15th datum before next stimulation was analyzed by three exponential models using a program in MATLAB 6.5. Both the goodness of fit and the distribution of the residuals for the best fitting supported the comparable validity of this new bi-exponential model for kinetic analysis of the relaxation process of the control muscles. After CPA treatment, however, this new bi-exponential model showed an obvious statistical superiority for kinetic analysis of the muscle relaxation process, and it gave the estimated rest tension consistent to that by experimentation, whereas both the classical bi-exponential model and the single exponential model gave biased rest tensions. Moreover, after the treatment of muscles by CPA, both the single exponential model and the classical bi-exponential model yielded lowered relaxation rates, nevertheless, this new bi-exponential model had relaxation rates of negligible changes except much higher rest tensions. These results suggest that this novel linearly-combined bi-exponential model is desirable for kinetic analysis of the relaxation process of muscles with altered Ca2^+-pumping activity. 相似文献
970.