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1.
The phagocytic ability of carp (Cyprinus carpio L.) granulocytes was evaluated in vivo and in vitro. In suspensions of head kidney cells, neutrophil granulocytes incorporated both latex beads and coccidian merozoites. In intestinal tissues from carp with a Goussia carpelli infection, all granulocyte cell types (neutrophils and cells of the basophilic-eosinophilic complex) phagocytosed cell detritus and coccidian developmental stages, mainly merozoites.  相似文献   

2.
以鲤鱼的成熟精巢为原料,经0.15 mol/L NaCl溶液浸提,硫酸解离,并分别经乙醇、丙酮分离提取鱼精蛋白。测定了鱼精蛋白对细菌和真菌的最低抑制浓度以及在不同pH条件下的抑菌特性,试验结果表明鱼精蛋白具有较好的热稳定性,与EDTA复合使用可以增强抑菌效果,在酱油中可以代替苯甲酸的防腐作用。  相似文献   

3.
The hatching performance of embryos of the common carp (Cyprinus carpio L.) was examined after 1, 7, 14, 21, or 28 days of storage at -8, -6, -4, -2, 0, 2, or 4 degrees C with different concentrations of methanol (0.5-7.0 M in 0.5 M steps) or varying concentrations of methanol in 0.1 M sucrose or trehalose. Preserved embryos failed to hatch after storage at -8 and -6 degrees C, regardless of the duration of storage or the concentrations tested. Likewise, there was no hatching out above 5.0 M concentration of methanol, even with the addition of sucrose or trehalose. After storage at 2 or 4 degrees C, the hatching rate was higher with mixtures of methanol (1.5 M) and trehalose (0.1 M) than with methanol plus sucrose or methanol alone. At 4 degrees C, the solution containing 1.5 M methanol supplemented with trehalose gave the highest hatching response of embryos stored for 14 days. Comparison of hatching after 24h of storage at the effective temperatures (-4, -2, 0, 2, and 4 degrees C) revealed that low concentrations of methanol were effective at high temperatures and high concentrations at sub-zero temperatures. The combination of 0.1 M trehalose with 1.5 M methanol gave the highest percentage hatching out both at 4 and 2 degrees C. At 0 degrees C, the highest percentage hatching occurred with 0.1 M trehalose plus 2.5 M methanol and at -2 and 4 degrees C, the best results were with 0.1 M trehalose plus 3.0 M methanol.  相似文献   

4.
One new (Sarsasapogenin O) and seven known steroids were isolated from the roots of Asparagus officinalis L. Their structures were elucidated on the basis of spectroscopic analysis, including various 2D-NMR techniques, hydrolysis,and by comparison of spectral data of known compounds. These compounds together with nine steroids which were previously isolated from this plant, were tested for cytotoxic activity. Among them, eight compounds displayed significant cytotoxicities against human A2780, HO-8910, Eca-109, MGC-803, CNE, LTEP-a-2, KB and mouse L1210 tumor cells.  相似文献   

5.
为研究竹黄菌与竹红菌化学成分及细胞毒活性的差异,本研究通过高效液相色谱(HPLC)分析结合常规色谱方法,分离鉴定了两种真菌的6个相同成分,分别为3个主要成分竹红菌甲素(1)、竹红菌乙素(2)和竹红菌丙素(3),以及3,6,8-三羟基-1-甲基口山酮(7)、3,8-二羟基-6-甲氧基-1-甲基口山酮(8)和过氧麦角甾醇(9)。另外,从竹黄菌中还分离得到11,11′-二去氧沃替西林(5)、麦角甾-7,22E-二烯-3β,5α,6β-三醇(10)和麦角甾-7,22E-二烯-2β,3α,9α-三醇(11),并首次从竹红菌中分离得到竹红菌丁素(4)、灰黄霉素(6)、化合物7和8。活性筛选发现,化合物5对三株肿瘤细胞NCI-H1975、HepG2和MCF-7有很强细胞毒活性,化合物1有较强细胞毒活性,而化合物6活性较弱。  相似文献   

6.
翅果藤的细胞毒活性和化学成分研究   总被引:3,自引:0,他引:3  
对翅果藤(Myriopteron extensum (Wight)K.Schum)的甲醇提取物及其不同的极性部位进行的细胞毒活性筛选发现乙酸乙酯、正丁醇部分具有一定的细胞毒活性。首次对其成分的研究分离得到7个化合物,通过波谱分析鉴定为β—谷甾醇,齐墩果酸,α—香树素乙酸酯,β—香树素乙酸酯,羽扇豆烷乙酸酯,乌沙甙元和胡萝卜甙。进一步的活性测试和化学研究仍在进行。  相似文献   

7.
Using electrophysiological methods, effects of temperature on rhythmic impulsation of spontaneously active neurons of thoracic ganglia was studied in grasshoppers Tettigonia cantans and Metrioptera roeselii. Several types of response to temperature changes were observed. Its elevation caused an increase or decrease of the discharge dispersion and a gradual, proportional or abrupt rise of the impulse rate. On decreasing temperature, the impulsation usually returned to its original state, although sometimes at different rate. In neurons whose impulse rate was close to that of pulse repetition rate in male advertisement calls, this dependence was preserved at temperature changes. On the whole, there is reason to believe that changes of temperature in CNS are accompanied not only by a simple change of the neuronal activity level, but also by a complex readjustment in the neuronal network functioning, which allow preserving optimal level of insect metabolic processes and adequate behavior.  相似文献   

8.
Electrophoretic light scattering has been used to study the effects of concavalin A (Con A) and succinyl-Con A on the electrophoretic mobility distribution of resident guinea-pig peritoneal eosinophils and human peripheral blood polymorphonuclear leukocytes. In both cell types, incubation with Con A (a tetrameric lectin) decreases slightly the mean mobility and increases substantially the width of the electrophoretic mobility distribution. These effects can be abolished by α-methyl-D-mannoside, a hapten sugar of Con A. Succinyl Con A, a dimeric derivative, was found to have no effect on the mobility distribution. These results are strikingly similar to our previous report of the response of the resident guinea-pig macrophage (19), suggesting possible parallels in the endocytic mechanisms of these cell types.  相似文献   

9.
Two growth trials using a range of ration sizes from starvation to maximum feeding suggested that linear relationships existed between specific growth rate and ration size for Nile tilapia and givel carp. Continuous measurement of activity showed that activity level, in terms of distance swum per day, was not affected significantly by ration size in both Nile tilapia and gibel carp.  相似文献   

10.
Spontaneous activity regulates many aspects of central nervous system development. We demonstrate that in the embryonic chick hindbrain, spontaneous activity is expressed between embryonic days (E) 6–9. Over this period the frequency of activity decreases significantly, although the events maintain a consistent rhythm on the timescale of minutes. At E6, the activity is pharmacologically dependent on serotonin, nACh, GABAA, and glycine input, but not on muscarinic, glutamatergic, or GABAB receptor activation. It also depends on gap junctions, t‐type calcium channels and TTX‐sensitive ion channels. In intact spinal cord‐hindbrain preparations, E6 spontaneous events originate in the spinal cord and propagate into lateral hindbrain tissue; midline activity follows the appearance of lateral activity. However, the spinal cord is not required for hindbrain activity. There are two invariant points of origin of activity along the midline, both within the caudal group of serotonin‐expressing cell bodies; one point is caudal to the nV exit point while the other is caudal to the nVII exit point. Additional caudal midline points of origin are seen in a minority of cases. Using immunohistochemistry, we show robust differentiation of the serotonergic raphe near the midline at E6, and extensive fiber tracts expressing GAD65/67 and the nAChR in lateral areas; this suggests that the medial activity is dependent on serotonergic neuron activation, while lateral activity requires other transmitters. Although there are differences between species, this activity is highly conserved between mouse and chick, suggesting that developmental event(s) within the hindbrain are dependent on expression of this spontaneous activity. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009  相似文献   

11.
Spontaneous electrical activity that moves in synchronized waves across large populations of neurons plays widespread and important roles in nervous system development. The propagation patterns of such waves can encode the spatial location of neurons to their downstream targets and strengthen synaptic connections in coherent spatial patterns. Such waves can arise as an emergent property of mutually excitatory neural networks, or can be driven by a discrete pacemaker. In the mouse cerebral cortex, spontaneous synchronized activity occurs for approximately 72 h of development centered on the day of birth. It is not known whether this activity is driven by a discrete pacemaker or occurs as an emergent network property. Here we show that this activity propagates as a wave that is initiated at either of two homologous pacemakers in the temporal region, and then propagates rapidly across both sides of the brain. When these regions of origin are surgically isolated, waves do not occur. Therefore, this cortical spontaneous activity is a bilateral wave that originates from a discrete subset of pacemaker neurons. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009  相似文献   

12.
2,2′-Diphenyl-3,3′-diindolylethylene (DPDIE) derivatives 3a-g were regioselectively prepared in one pot from indoles 1a-g in the presence of Lewis acids and were subsequently evaluated for cytotoxic activity against human leukemic cell lines, U937 and K562. The most potent compound 3g exhibited IC50 of 13.0-17.0 μM.  相似文献   

13.
Fatty acid synthase (FAS) has been proposed to be a new drug target for the development of anticancer agents because of the significant difference in expression of FAS between normal and tumour cells. Since a n-hexane-soluble extract from Ginkgo biloba was demonstrated to inhibit FAS activity in our preliminary test, we isolated active compounds from the n-hexane-soluble extract and evaluated their cytotoxic activity in human cancer cells. Three ginkgolic acids 13 isolated from the n-hexane-soluble extract inhibited the enzyme with IC50 values 17.1, 9.2 and 10.5 µM, respectively, and they showed cytotoxic activity against MCF-7 (human breast adenocarcinoma), A549 (human lung adenocarcinoma) and HL-60 (human leukaemia) cells. Our findings suggest that alkylphenol derivatives might be a new type of FAS inhibitor with cytotoxic activity.  相似文献   

14.
为研究白花银背藤(Argyreia seguinii)的生物碱类成分及其细胞毒活性,该研究采用硅胶、ODS、Sephadex LH-20及半制备HPLC等柱色谱法对白花银背藤的75%乙醇提取物进行分离纯化,根据理化性质及波谱数据鉴定化合物的结构,并通过MTS法检测化合物对5种肿瘤细胞的增殖抑制活性。结果表明:从白花银背藤中分离得到9个生物碱类化合物,分别鉴定为N-反式桂皮酰对羟基苯乙胺(1)、N-反式对香豆酰基酪胺(2)、N-反式阿魏酰酪胺(3)、N-顺式阿魏酰酪胺(4)、1H-吲哚-3-甲醇(5)、金色酰胺醇酯(6)、8-氧-四氢巴马亭(7)、8-oxypalmatine(8)和12,13-dihydro-8-oxoberberine(9)。其中,化合物1、4-9均为首次从该植物中分离得到,化合物7和化合物8对肝癌SMMC-7721细胞显示细胞毒活性,半抑制浓度(IC50)值分别为(15.50±0.76)、(14.24±0.72)μmol·L-1。该研究结果为进一步探讨白花银背藤的化学成分和药理活性奠定了基础,为厘清壮药“一匹绸”的药材基原...  相似文献   

15.
Nanotechnology is an emerging field with tremendous potential and usage of medicinal plants and green preparation of nanoparticles (NPs) is one of the widely explored areas. These have been shown to be effective against different biological activities such as diabetes mellitus, cancer, antioxidant, antimicrobial, etc. The current studies focus on the green synthesis of zinc NPs (ZnO NPs) from aqueous leaf extract of Murraya koenigii (MK). The synthesized Murraya koeingii zinc oxide NPs (MK ZnO NPs) were characterized using UV–visible spectroscopy, dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), energy-dispersive spectrum (EDS) and cyclic voltammetry (CV). The synthesized MK ZnO NPs were evaluated for their in vitro antidiabetic, antioxidant, antimicrobial, and cytotoxic activity. They demonstrated significant antidiabetic and cytotoxic activity, as well as moderate free-radical scavenging and antibacterial activity.  相似文献   

16.
Sarah G. Leinwand  Kristin Scott 《Neuron》2021,109(11):1836-1847.e5
  相似文献   

17.
Established methods for isolating intraepithelial lymphocytes (IEL) from mouse small intestine were modified to facilitate the isolation of IEL from rainbow trout gut epithelium. A 1 h incubation in 1 mMDTT/EDTA was required to maximise the separation of the epithelial compartment from the underlying lamina propria. Epithelial cell content was reduced by filtration on nylon wool columns followed by centrifugation on a 40% Percoll cushion. Most IEL pelleted through the 40% Percoll [high density (HD) IEL] although significant numbers banded out at the medium/40% Percoll interface [low density (LD) IEL]. The majority (∼90%) of HD IEL were<12·5 μm in size, had a pleiomorphic nucleus and obvious mitochondria. LD IEL were larger cells, containing more cytoplasm with abundant ribosomes. Neither HD nor LD IEL appeared to contain ‘ cytotoxic ’ granules. Despite this, in a non-radioactive cytotoxicity assay (LDH release) with EL4 mouse thymoma cells as targets, significant killing was observed by both the HD and LD IEL.  相似文献   

18.
Spontaneous waves of activity that propagate across large structures during specific developmental stages play central roles in CNS development. To understand the genesis and functions of these waves, it is critical to understand the spatial and temporal patterns of their propagation. We recently reported that spontaneous waves in the neonatal cerebral cortex originate from a ventrolateral pacemaker region. We have now analyzed a large number of spontaneous waves using calcium imaging over the entire area of coronal slices from E18‐P1 mouse brains. In all waves, the first cortical region active is this ventrolateral pacemaker. In half of the waves, however, the cortical pacemaker activity is itself triggered by preceding activity in the septal nuclei. Most waves are restricted to the septum and/or ventral cortex, with only some invading the dorsal cortex or the contralateral hemisphere. Waves fail to propagate at very stereotyped locations at the boundary between ventral and dorsal cortex and at the dorsal midline. Waves that cross these boundaries pause at these same locations. Waves at these stages are blocked by both picrotoxin and CNQX, indicating that both GABAA and AMPA receptors are involved in spontaneous activity. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 70: 679–692, 2010  相似文献   

19.
Six polymethoxylated flavonoids were isolated from ethyl acetate fraction of ethanol extracts from Vitex rotundifolia Linn. f. fruit, and their structures were identified by NMR and MS methods, and cyt...  相似文献   

20.
Synaptically driven spontaneous network activity (SNA) is observed in virtually all developing networks. Recurrently connected spinal circuits express SNA, which drives fetal movements during a period of development when GABA is depolarizing and excitatory. Blockade of nicotinic acetylcholine receptor (nAChR) activation impairs the expression of SNA and the development of the motor system. It is mechanistically unclear how nicotinic transmission influences SNA, and in this study we tested several mechanisms that could underlie the regulation of SNA by nAChRs. We find evidence that is consistent with our previous work suggesting that cholinergically driven Renshaw cells can initiate episodes of SNA. While Renshaw cells receive strong nicotinic synaptic input, we see very little evidence suggesting other spinal interneurons or motoneurons receive nicotinic input. Rather, we found that nAChR activation tonically enhanced evoked and spontaneous presynaptic release of GABA in the embryonic spinal cord. Enhanced spontaneous and/or evoked release could contribute to increased SNA frequency. Finally, our study suggests that blockade of nAChRs can reduce the frequency of SNA by reducing probability of GABAergic release. This result suggests that the baseline frequency of SNA is maintained through elevated GABA release driven by tonically active nAChRs. Nicotinic receptors regulate GABAergic transmission and SNA, which are critically important for the proper development of the embryonic network. Therefore, our results provide a better mechanistic framework for understanding the motor consequences of fetal nicotine exposure. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 298–312, 2016  相似文献   

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