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171.
Sujuan  Wang  Zhidong  Xu 《Hydrobiologia》1984,110(1):213-217
A study of food and food selection of Penaeus monodon (Fabricius) on the Sudanese Red Sea coast was carried out. Juveniles feed mainly on algal material. Adults feed on crustacea, annelids, algae, mud and unidentified matter. Adults were opportunistic in their feeding behaviour, but their preference was towards animal protein.Antennae, mouth parts and fore-chelipeds were found to carry long, slender setae which are probably of sensory function. Some setae on the carpus of the endopodite were serrated and seem to be used in grooming. Numerous tufts of setae in the chela of the fore periopods may hold a gustatory function. The inner edges of the chela are lined with a row of peg-like setae, which are probably another site of reception.  相似文献   
172.
Rats were treated with highly purified gossypol acetic acid at doses of 15 or 30 mg/kg day-1 for 6 weeks to produce an effect on spermatogenesis as shown by reduced sperm motility and increased sperm malformation rates. The treated rats did not differ from the controls in the body weight growth curves and reproductive organ weights. When stimulated with hCG, testicular blood flow was increased in the low dose group; the testosterone concentrations in peripheral and testicular venous blood were also increased to a greater extent than those of the control group. No difference was found between the high dose and control groups in testicular blood flow or testosterone concentrations. The morphology of the Leydig cells was apparently normal, although some degenerative changes in the germinal epithelium were observed in the high dose group. Therefore, there is no evidence in our experiment to show any anti-androgenic effect following 6-week treatment of gossypol in rats, even at the dose of 30 mg/kg day-1.  相似文献   
173.
A newly discovered bioactive peptide, neuropeptide Y (NPY), has been found in the innervation of the mouse and rat heart by immunocytochemistry, NPY-immuno-reactive nerves were very dense around the nodal tissues. They also surrounded the coronary arteries and arterioles and were found in close association with the cardiac muscle. The distribution of NPY-containing nerves paralleled that of noradrenergic fibers, demonstrated by the use of antibodies to the catecholamine-converting enzymes tyrosine hydroxylase and dopamine beta-hydroxylase. Furthermore, NPY was seen to be present in a proportion of intrinsic neurons mostly found in the atria and in close proximity to the nodal tissue. The concentrations of extractable NPY-immunoreactive material (about 150 pmol/g in whole mouse heart) by far surpasses those of the other peptides so far reported in the cardiac tissue. High performance liquid chromatography demonstrated the NPY immunoreactivity to elute in a single sharp peak, in an identical position to brain NPY.  相似文献   
174.
培养抗性植物的细胞/组织培养途径   总被引:3,自引:0,他引:3  
抗性育种在作物品种改良中已日益显得重要。近10多年来,随着细胞/组织培养、遗传操作等生物技术的迅速发展,以及由于植物具有全能性,在人工培养条件下,从单细胞原生质体可以再生成一个完整的个体成功以来,人们试图利用细胞/组织培养等生物技术将野生种的抗性基因引入到作物中来,或是人工诱发抗性变异,从而筛选出抗性愈  相似文献   
175.
 <正> 补体成分的多态现象,特别是对人C4多态现象的研究,是近年来补体研究进展的一个重要方面。1969年Roseufeld等报告了人补体C4的多态现象以后,Teisberg等(1976)率先应用免疫固定电泳研究C4多态现象。这是当前研究补体多态现象的通用方法。1978年O’Neill等报告人的C4F和C4S分别由C4A和C4B两个基因座位控制,并分别与Rodgers和Chido血型抗原相应。现已发现C4A共有13个别型,C4B共有22个别型。  相似文献   
176.
 <正> 1980年,Hunter首次发现Rous肉瘤病毒转化的细胞,其蛋白质分子上的酪氨酸残基磷酸化水平明显升高。现已知道,其它的肿瘤病毒诱导的转化细胞以及某些恶性肿瘤细胞的酪氨酸残基磷酸化作用亦有不同程度的增强。但迄今物理的致癌因素如放射性同位素引起的细胞转化是否伴随着酪氨酸特异的磷酸化的增强,尚未见报道。因此,本实验对C_3H10  相似文献   
177.
诸葛菜组织培养中的器官形成   总被引:3,自引:0,他引:3  
植物组织和细胞培养技术已在农作物的改良及园艺植物的快速繁殖方面得到广泛的应用。在这方面,十字花科植物正在受到相当多的注意。新近,为了建立十字花科植物的细胞转化系统,我们试验了多种十字花科植物,发现诸葛菜的叶和叶柄等外植体具有极强的器官分化能力,现将结果报告如下。本文取材植物诸葛菜,又名二月兰(Oryc-hophragmus violaceus/Moricandia sonchifolia),  相似文献   
178.
贵州产宽叶缬草(Valeriana officinalis L.var.latifolia Miq.)油,用Finnigan4510型毛细管气相色谱/质谱/计算机联用方法进行了化学成分分析,共检出了29个成分鉴定了其中21个成分,占全精油的92.33%,主要成分为乙酸龙脑酯,α-蒎烯,莰烯,β-蒎烯,柠檬烯,乙酸葛缕酯,二氢乙酸葛缕酯等。该油芬芳,适于调配烟用香精,亦用于调节器配食用香精和化妆品香精。  相似文献   
179.
Sixty depressed patients and 52 normal controls completed three selfreport inventories: the Symptom Checklist-90 (SCL-90), the Beck Depression Inventory (BDI) and a new Verbal Style Investigation Schedule (VESIS) developed by the first author. The VESIS uses 16 key emotional and physical terms from Western inventories and identified the words and phrases most commonly used by Chinese patients to express these feeling states. Chinese subjects commonly used the key term itself for only 3 or the 16 key terms; they usually preferred to use other words or phrases to express the feeling state. We categorized these Chinese expressions into four styles of verbal expression: Psychological, Somatic, Neutral (i.e., a mixture of psychological and somatic) and Deficient (i.e., lack of expression because of denial or suppression). Three of the 12 key emotional terms of the VESIS (depressed, fearful, and anxiousness) were more commonly expressed in a somatic or neutral mode than the other key emotional terms. The key terms suicidal interest and being punished were more commonly expressed in a deficient style than other key emotional terms. The somatic factor score of the SCL-90 was not correlated with increased somatic expression of emotional states; thus patients who have multiple somatic complaints are not more likely to express emotions somatically. The hypothesis of somatization is discussed in light of this study.  相似文献   
180.
落葵(Basella rubra L.)小孢子的发育为同时型,四分体呈四面体排列。在花粉母细胞减数分裂过程中,可清楚地看到胼胝壁的消长变化。三胞花粉,具散沟和网状纹饰。腺质绒毡层。 胚囊的发育为蓼型。反足细胞早期退化。内珠被突出形成珠被喙,同时,在其珠孔区域,有由内珠被的内表皮细胞所发育而来的类似盖状结构。 本文还注意到同一花中以及相邻花朵之间,花粉粒与胚囊发育进程的相关。花粉粒的发育略早于胚囊的发育,但以后由于胚囊母细胞形成胚囊的进程较为迅速,以致花粉粒与胚囊能够同时成熟。  相似文献   
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