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971.
V T Kondakov A B Okulov M A Filippkin R Z Tandilava I U Artamonov O A Voronenko A N Sazonov 《Vestnik rentgenologii i radiologii》1991,(4):31-35
The paper is concerned with analysis of the results of intraoperative phlebotesticulography, performed in 50 patients with varicocele of degree I-II during Ivanissevich's operation. The effect of surgical intervention was shown to depend upon the quality of ligation of the testicular vein, some parts of which are anastomosed between themselves. The localization of this anastomosis is revealed by means of intraoperative phlebotesticulography, which permits increasing the results of surgical treatment and predicting a course of a postoperative period. 相似文献
972.
973.
Hypoxia modulates cyclin and cytokine expression and inhibits peripheral mononuclear cell proliferation. 总被引:5,自引:0,他引:5
Previously, we found that hypoxia can deeply affect the production of cytokines in human peripheral mononuclear cells (PBMC). Here, we demonstrated that the cycle progression of hypoxic PBMC, cultured in the presence or not of a specific T cell activator such as phytohaemagglutinin (PHA), was delayed when compared with aerobic cultures. This delay was accompanied by a decrease of the expression of specific cyclins associated to cell cycle progression phases. Ribonuclease Protection Assay (RPA) studies reveal a decrease in the expression of cyclin A and B in PHA-stimulated PBMC kept for 40 hr under hypoxic condition (2% O(2)), when compared with aerobic cultures (20% O(2)). In concomitance, a decrease of cyclin D2 expression was present after 16 hr of hypoxic treatment. However, the decrease was transient and disappeared after 40 hr of hypoxic treatment. Furthermore, cyclin C expression was not affected by hypoxia. Hypoxia-induced cyclin modulation was accompanied by an increased synthesis of interleukin (IL)-2 and IL-4, analyzed by ELISA. By evaluating these results, it appears that hypoxia induces a growth suppressive state in mitogen-activated PBMC by inhibiting the synthesis of mitotic cyclins A and B. However hypoxic PBMC maintain their viability and capability of producing stimulatory cytokines, after mitogen treatment. This should be important in local hypoxia, usually associated with necrotic areas, in inflammation, and infections, where T lymphocyte capability of producing stimulatory cytokines is desirable. 相似文献
974.
Toxicity of Dopamine to Striatal Neurons In Vitro and Potentiation of Cell Death by a Mitochondrial Inhibitor 总被引:8,自引:2,他引:6
B. A. McLaughlin †D. Nelson †‡M. Ereciska † M.-F. Chesselet 《Journal of neurochemistry》1998,70(6):2406-2415
Abstract: Intrastriatal injections of the mitochondrial toxins malonate and 3-nitropropionic acid produce selective cell death similar to that seen in transient ischemia and Huntington's disease. The extent of cell death can be attenuated by pharmacological or surgical blockade of cortical glutamatergic input. It is not known, however, if dopamine contributes to toxicity caused by inhibition of mitochondrial function. Exposure of primary striatal cultures to dopamine resulted in dose-dependent death of neurons. Addition of medium supplement containing free radical scavengers and antioxidants decreased neuronal loss. At high concentrations of the amine, cell death was predominantly apoptotic. Methyl malonate was used to inhibit activity of the mitochondrial respiratory chain. Neither methyl malonate (50 µ M ) nor dopamine (2.5 µ M ) caused significant toxicity when added individually to cultures, whereas simultaneous addition of both compounds killed 60% of neurons. Addition of antioxidants and free radical scavengers to the incubation medium prevented this cell death. Dopamine (up to 250 µ M ) did not alter the ATP/ADP ratio after a 6-h incubation. Methyl malonate, at 500 µ M , reduced the ATP/ADP ratio by ∼30% after 6 h; this decrease was not augmented by coincubation with 25 µ M dopamine. Our results suggest that dopamine causes primarily apoptotic death of striatal neurons in culture without damaging cells by an early adverse action on oxidative phosphorylation. However, when combined with minimal inhibition of mitochondrial function, dopamine neurotoxicity is markedly enhanced. 相似文献
975.
976.
977.
Summary Worldwide, invasive weeds threaten agricultural, natural and urban ecosystems. In Australia's agricultural and grazing regions, invasive species often establish across extensive areas where weed management is hampered by an inability to detect the location and timing of an outbreak. In these vast landscapes, an effective detection and monitoring system is required to delineate the extent of the invasion and identify spatial and temporal factors associated with weed establishment and thickening. In this study, we utilize a time series of remote sensing imagery to detect the spatial and temporal patterns of Prickly Acacia ( Acacia nilotica ) invasion in the Mitchell grass plains of North Queensland. We develop a spectral index from Landsat images which is applied to images from 1989 to 2004, in combination with a classification mask, to identify locations and monitor changes in Prickly Acacia density across 29 000 km2 of Mitchell grass plains. The approach identified spectral and temporal signatures consistent with Prickly Acacia infestation on 1.9% of this landscape. Field checking of results confirmed presence of the weed in previously unrecorded locations. The approach may be used to evaluate future spread, or outcomes of management strategies for Prickly Acacia in this landscape and could be employed to detect and monitor invasions in other extensive landscapes. 相似文献
978.
C K?nig Y L Yan J Postlethwait S Wendler J A Campos-Ortega 《Mechanisms of development》1999,86(1-2):17-28
We describe the characterization of the zebrafish homologue of the human gene DLG3. The zebrafish dlg3 gene encodes a membrane-associated guanylate kinase containing a single PDZ domain. This gene was cloned using a gene-trap construct inserted in the gene's first intron. The insertion co-segregates with a viable mutation called humpback (hmp), which leads to formation of ankylotic vertebrae in adult fishes. Insertion and mutation have both been mapped to chromosome 12, in a segment which is syntenic with region p12 to q12 of human chromosome 17. The hmp mutant phenotype, however, appears to be due to two point mutations in the guanylate kinase domain rather than to the transgene insertion itself. The results of this study are discussed in the light of the possible function of the guanylate kinase domain. 相似文献
979.
R G Pankov A A Uschewa B T Tasheva P T Petrov G G Markov 《Cell biology international reports》1985,9(11):1003-1011
A dominating protein fraction (p45) having molecular weight of 45000 and pI 5.45 was found in the intermediate filaments pellet obtained from rat liver besides the present cytokeratins. Peptide mapping and radioimmunological assays with antibodies against this protein and muscle actin proved that the p45 protein belongs to the actin group. Immunoelectron microscopy revealed that this protein is located on the liver intermediate filaments. By melting of the cytokeratin complexes in urea it was established that p45 protein is complexed with the low molecular weight cytokeratin. 相似文献
980.
A strain of 1,507 typised donors enables 15.97 average donors to be selected for a thrombocyte transfusion in one of 75 patients selected at random with HLA antibodies being previously determined (1 to 66 donors per patient). HLA compatible donors were found for 72 patients (97.33 per cent). More than 5 HLA compatible donors could be found for 58 patients. The high number of compatible donors is based on the fact that among 1,507 donors there were 156 HLA homozygotes and 556 donors with 3 HLA-A or B-antigens respectively. Compatibility in the ABO-system was not taken into account. 相似文献