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961.
962.
N. B. Mel’nikova A. A. Volkov S. V. Kononova T. A. Krainova L. M. Efremova V. V. Anastasiev 《Pharmaceutical Chemistry Journal》2006,40(5):284-288
Features of the interaction of doxorubicin (DR) with Cu2+ ions of the active center of ceruloplasmin (CP) have been studied by electronic spectroscopy. It is established that DR ·
Cu2+ CP and DR complexes with inorganic copper salts (Cu(CH3COO)2 and CuSO4) have the same chromophore. An equation establishing a relationship between the electronic absorption at 540 nm (chromophore
absorption region) and the concentration of DR involved in the complex formation is proposed. Using this dependence in accordance
with the Benesi-Hildebrand theory, the complex formation constant was approximately evaluated as Kp = 4.5 × 106. Effective complex formation between DR and Cu2+ ions of the CP active center creates prerequisites for the removal of Cu2+ ions from CP and, consequently, for a decrease in CP oxidase activity.
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Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 5, pp. 49–53, May, 2006. 相似文献
963.
964.
R. I. Lifshits S. L. Sashenkov B. M. Val'dman V. P. Bordunovskaya G. P. Efimenko N. V. Egorova A. V. Volkov I. A. Volchegorskii 《Bulletin of experimental biology and medicine》1988,106(6):1691-1694
Departments of Biochemistry and Normal Physiology, Chelyabinsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Orekhovich.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 106, No. 12, pp. 666–668, December, 1988. 相似文献
965.
966.
967.
The incidence of small renal cell carcinomas (RCC) has Increased recently as diagnostic imaging techniques have improved. The Indications for partial nephrectomy for small RCC confined to the kidney are still controversial. Ninety-seven small RCC 2.5 cm or smaller, Including incidental, occult, and dialysis associated carcinomas obtained at surgery or autopsy were examined. Various clinicopathologic parameters were assessed and survival was analyzed using the Kaplan-Meir method. Seventy-eight cases were incidental carcinomas. Carcinomas caused death in five cases, four of which had Initial signs of metastatic disease. Differences in survival between patients with expansive and invasive (intermediate and infiltrating) growth patterns, solid and other structural patterns, clear and other cell types, grade 1 and higher grades of nuclear atypla, and with and without lymph node metastasis were statistically significant All surgical cases were alive except one who died of another disease. Poor prognostic factors seen in five fatal autopsy cases included invasive growth pattern, solid structural pattern, spindle cells, grade 3 nuclear atypia, and Bellini duct carcinoma. Small RCC may be treated with partial nephrectomy provided they do not show these features, although there is low risk of recurrence or development of de novo cancer. 相似文献
968.
Interaction of neurons with tonic response to sound with adjacent or distant (approximately 400-500 micrograms) cortex neurons was studied in acute experiments on 15 immobilized cats using a method of the cross-correlation analysis. A presence of synchronizing excitatory input common for the cells has been revealed in 26 pairs (72%) on the cross-correlograms. The results of the cross-correlation analysis in five pairs of neurons show mono- or polysynaptic excitatory effect of a tonic neuron to impulse activity of another neuron. Negative correlation indicative of the inhibitory influence of tonic neurons on impulse responses of other neurons of the same or adjacent auditory cortex column is revealed in five pairs of neurons, but the inhibitory influences may be considered as monosynaptic ones only in 3 pairs of these neurons (latency of interaction 1.0-1.5 ms). The data obtained permit concluding that the group of neurons characterized by tonic response to sound is a heterogeneous one in the functional respect. An assumption that some neurons of the tonic type are inhibitory interneurons of the auditory cortex, other excitatory ones is under discussion. 相似文献
969.
Nakashima Emi Kubota Yuri Matsushita Ryo Ozaki Eijiro Ichimura Fujio Kawahara Sakae Nakanishi Isao Kuno Kouji Matsushima Kouji 《Pharmaceutical research》1998,15(5):685-689
Purpose. In order to evaluate the possibility of synergistic antitumor gene therapy by the gene delivery of monocyte chemotactant protein-1 (MCP-1/MCAF/IE), the effect of a biological response modulater for macrophages on tumor progression of gene transfected tumor cells was studied.
Methods. Cachexia-inducing adenocarcinoma cells (cell line colon 26, clone 20) were transfected with either a control plasmid or MCP-1 cDNA.
Results. The production of MCP-1 reached 70-80 ng/ml in vitro when transfectant cells were cultured at a cell density of 1 × 105 cells/ml for 3 days. Transfection of MCP-1 cDNA did not affect the growth ratein vitro. Also, MCP-1-transfectants formed tumors after intra-footpad inoculation similar in size to the parental cells. The number of infiltrating macrophages in the primary tumor of the transfectant rapidly increased from the 3rd to 5th day after inoculation as revealed by immunohistochemical staining using an antibody against mouse macrophages. An earlier, greater, but no longer-lasting increase in tumor-infiltrating macrophages was induced in tumors by MCP-1 transfection was compared to that induced by the parent cells. On the 10th day after the inoculation, the tumor-infiltrating macrophages in mice inoculated MCP-1 transfectants were decreased to a level similar to that of the parent cells. Groups of mice were treated intraperitoneally with LPS at different times after the inoculation. Tumor cells producing high levels of MCP-1 were significantly lysed by macrophages treated with LPS, whereas parental or control transfected cells were not.
Conclusions. Combination immunotherapy can provide a rationale for the application of MCP-1 treatment to increase immunological responses to cancer. 相似文献
970.
The effect of 17β-estradiol (E2)_treatment for 28 days on tyrosine hydroxylase-immunoreactive (TH-IR) neurons in the periventricular preoptic nucleus (PPN) and medial preoptic area (MPA) of ovariectomized (OVX) rats was examined by morphometric analysis. The number of TH-IR nuerons in the PPN of the E2-treated group was smalle than that of the OVX group, whereas the opposite result was found in the MPA; the number of TH-IR neurons in the MPA of the E2-treated group was larger than that of the OVX group. Numerous TH-IR neurons were found in the ventromedial portion of the MPA of the E2-treated group. In both the OVX and E2-treated groups, TH-IR neurons contained many short processes up to 40 μm in length. E2 treatment caused a significant decrem,ent of the number of neurons containing the processes in the range of 10–40 μm length in the PPN, however it caused a significant increment of the number of neurons containing the processes in the range of 5–10 μm length in the MPA. These results suggested that immunoreactivity of TH in the PPN and MPA neuron are affected by E2 treatment and that E2 might modulate the production of TH in a region-specific pattern within the hypothalamus of the female rat. 相似文献