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1.
Using cytochemical method,microspectrophotometry and image analysis,effects of va-soactive intestinal peptide(VIP)on activities of succinic dehydrogenase(SDH)and alkalinephosphatase(ALP)in rat hepatoma cells were studied in vitro.The results showed that thehepatoma cell expressed potent positive reactions of SDH and ALP,the positive positionswere located at the cell membranes and/or cytoplasm.Having been treated with VIP,ALPdecreased obviously in activity(P<0. 01,compared with hepatoma cells untreated by VIP).The sites of ALP activty were chiefly located at the cell membranes,particularly at the cell-cell contacts.Cultured rat hepatoma cells had intensive SDH activity in their cytoplasm.Compared with untreated eclls,there was no marked difference in the intensity of SDH activ-ity in VIP-treated hepatoma cells(P>0.05).  相似文献   
2.
An isolate ofConidiobolus coronatus (NCIM 1238) showed high proteinase activity (20.1 U/ml) and productivity (600 U/l.h) when 1% (w/v) glucose or sucrose was used as the carbon source in shake flasks. Addition of organic nitrogen sources, casein (2%), soybean flour (4%), liver extract (2%) or Edamin-S (2%), enhanced growth and proteinase production up to three-fold and seven-fold, respectively. The system was successfully run up to 6 l in a laboratory fermenter with a productivity of 600 U/l.h. The proteinase was successfully used to resolve the recemic mixtures ofdl-phenylalanine anddl-phenylglycine and thus could replace the currently used subtilisin.  相似文献   
3.
We describe the synthesis, MMP-2 and 9 potency, and in vitro evaluation of a series of α-sulfone hydroxmate MMP inhibitors conjugated to a series of dyes with different absorption/emission lamina maxima’s that can be used to visualize tumors.  相似文献   
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Insect neurons are individually identifiable and have been used successfully to study principles of the formation and function of neuronal circuits. In the fruitfly Drosophila, studies on identifiable neurons can be combined with efficient genetic approaches. However, to capitalise on this potential for studies of circuit formation in the CNS of Drosophila embryos or larvae, we need to identify pre- and postsynaptic elements of such circuits and describe the neuropilar territories they occupy. Here, we present a strategy for neurite mapping, using a set of evenly distributed landmarks labelled by commercially available anti-Fasciclin2 antibodies which remain comparatively constant between specimens and over developmental time. By applying this procedure to neurites labelled by three Gal4 lines, we show that neuritic territories are established in the embryo and maintained throughout larval life, although the complexity of neuritic arborisations increases during this period. Using additional immunostainings or dye fills, we can assign Gal4-targeted neurites to individual neurons and characterise them further as a reference for future experiments on circuit formation. Using the Fasciclin2-based mapping procedure as a standard (e.g., in a common database) would facilitate studies on the functional architecture of the neuropile and the identification of candiate circuit elements.  相似文献   
6.
Based on the conjugate strategy, two neutral 99mTc labeled 2-(1-(6-(dialkylamino)naphthalen-2-yl)ethylidene)malononitrile (DDNP) and 1-(6-(dialkylamino)naphthalen-2-yl)ethanone (ENE) derivatives, and their corresponding rhenium complexes were synthesized. In vitro fluorescent staining indicated that the corresponding rhenium derivatives selectively stained the β-amyloid (Aβ) plaques in the brain sections of AD model mice with low background. Compared with FDDNP and FENE, the affinities of the corresponding rhenium derivatives to Aβ aggregates decreased about 10-14-fold. In vivo biodistribution experiments in normal mice showed that 99mTc-MAMA-ENE displayed medium initial brain uptake (0.65 %ID/g at 2 min) with a reasonable washout from the brain (0.19 %ID/g at 2 h) while 99mTc-MAMA-DDNP showed a low brain uptake (0.28 %ID/g at 2 min). Further optimize these 99mTc-labeled tracers in order to improve their binding affinities to Aβ plaques and diffusion through the blood brain barrier may generate useful imaging agents for SPECT.  相似文献   
7.
    
The effects of growth hormone (GH) implants on aggression, and ability to win dyadic territorial conflicts were studied in brown trout Salmo trutta parr. Bovine GH or vehicle (C) was given to either the territory owner or the intruder in four treatment combinations: C and C, C and GH, GH and C, GH and GH (owner and intruder). GH‐treated intruders initiated significantly more conflicts compared to control intruders. Furthermore, GH treatment of either the owner or intruder tended to increase aggression of the intruder. This indicates that intruders have more scope for motivational increase, while the motivation of owners is already at a maximum. The GH treatment, however, did not affect the outcome of the conflict. It thus appears that growth enhancement increases intruder aggression without increasing the chance of winning the conflict, which may have implications for the effect of growth‐selected or growth‐enhanced farmed Atlantic salmon Salmo salar on wild populations.  相似文献   
8.
This article examines the impact of the UN Law of the Sea Convention on conflict behavior and management in the South China Sea during four periods: during its negotiation (1973–1982); from its signing to the entry into force (1982–1994); from then until the China-ASEAN Declaration on the Conduct of Parties in the South China Sea (1995–2002); and from the setting of a timeline for outer limits of continental shelf submissions to the events following the 2009 submissions (2003–2013). Ambiguous effects were found. On the one hand, the Convention has generated or exacerbated conflict by raising the stakes, failing to resolve key legal issues, and encouraging overlapping zone claims. On the other hand, it has provided obligations, language, and techniques for conflict management and resolution. The conflict-enhancing impact was found to have been more substantial than the peace-promoting effects. Nevertheless, the balance has shifted toward more emphasis on conflict management and also some utilization of the Convention's peacemaking potential. If this long-term trend continues and the Convention is more rigorously respected and applied, the Convention may in the end be found to have contributed to regional peace.  相似文献   
9.
    
Around 10 million fatalities were recorded worldwide in 2020 due to cancer and statistical projections estimate the number to increase by 60% in 2040. With such a substantial rise in the global cancer burden, the disease will continue to impose a huge socio-economic burden on society. Currently, the most widely used clinical treatment modality is cytotoxic chemotherapy using platinum drugs which is used to treat variety of cancers. Despite its clinical success, critical challenges like resistance, off-target side effects and cancer variability often reduce its overall therapeutic efficiency. These challenges require faster diagnosis, simultaneous therapy and a more personalized approach toward cancer management. To this end, small-molecule ‘theranostic’ agents have presented a viable solution combining diagnosis and therapy into a single platform. In this review, we present a summary of recent efforts in the design and optimization of metal-based small-molecule ‘theranostic’ anticancer agents. Importantly, we highlight the advantages of a theranostic candidate over the purely therapeutic or diagnostic agent in terms of evaluation of its biological properties.  相似文献   
10.
    
Despite a positive correlation between chronic kidney disease and atherosclerosis, the causative role of uremic toxins in leukocyte-endothelial interactions has not been reported. We thus examined the effects of indoxyl sulfate, a uremic toxin, on leukocyte adhesion to activated endothelial cells and the underlying mechanisms. Pretreatment of human umbilical vein endothelial cells (HUVEC) with indoxyl sulfate significantly enhanced the adhesion of human monocytic cells (THP-1 cell line) to TNF-α-activated HUVEC under physiological flow conditions. Treatment with indoxyl sulfate enhanced the expression level of E-selectin, but not that of ICAM-1 or VCAM-1, in HUVEC. Indoxyl sulfate treatment enhanced the activation of JNK, p38 MAPK, and NF-κB in TNF-α-activated HUVEC. Inhibitors of JNK and NF-κB attenuated indoxyl sulfate-induced E-selectin expression in HUVEC and subsequent THP-1 adhesion. Furthermore, treatment with the NAD(P)H oxidase inhibitor apocynin and the glutathione donor N-acetylcysteine inhibited indoxyl sulfate-induced enhancement of THP-1 adhesion to HUVEC. Next, we examined the in vivo effect of indoxyl sulfate in nephrectomized chronic kidney disease model mice. Indoxyl sulfate-induced leukocyte adhesion to the femoral artery was significantly reduced by anti-E-selectin antibody treatment. These findings suggest that indoxyl sulfate enhances leukocyte-endothelial interactions through up-regulation of E-selectin, presumably via the JNK- and NF-κB-dependent pathway.  相似文献   
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