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991.
目的:研究二乙烯三胺五醋酸三钠锌盐及三钠钙盐注射液的离子对高效液相色谱测定。方法:以ODS(5μm,5mm×150mm)为色谱柱,流动相为甲醇-0.05mol/L醋酸钠缓冲液(pH4.5)(5:95),内含5mmol/L四丁基碘化胺,内标物为乙二胺四乙酸二钠,二乙烯三胺五醋酸(DTPA)及乙二胺四乙酸,(EDTA)与Fe~(3 )螯合成DTPA-Fe(Ⅲ)和EDTA-Fe(Ⅲ)复合物,其检测波长为280nm。结果:二乙烯三胺五醋酸的线性范围在20~320μg/ml,其三钠锌盐和三钠钙盐注射液5次测定的平均回收率±RSD分别为(101.33±0.65)%和(100.59±0.58)%。结论:此法重现性好,灵敏、特异,消除了多种金属离子的干扰。 相似文献
992.
993.
MC Smeets CB Vernooy JHM Souverijn MD Ferrari 《Cephalalgia : an international journal of headache》1994,14(1):29-32
Familial hemiplegic migraine (FHM) is an autosomal dominant type of migraine and probably represents the most extreme end of migraine with aura. Reduced magnesium facilitates the development of spreading depression and possibly aura. Cellular magnesium levels are under genetic control. We hypothesized that FHM patients would have significantly reduced intracellular magnesium levels. We determined intracellular and plasma magnesium levels in blood of 38 afflicted and 11 non-afflicted members of three families with FHM and, in 32 migraine patients (9 with and 23 without aura) and 32 age and sex matched healthy controls. We found no significant differences between the magnesium levels in the five study groups. We conclude that reduced blood magnesium is unlikely to be related to migraine pathophysiology. 相似文献
994.
Background
Manipur and Nagaland in northeast India are among the Indian states with the highest prevalence of HIV. Most prevention and care programs focus on identified "high risk" groups, but recent data suggest the epidemic is increasing among the general population, primarily through heterosexual sex. People with disability (PWD) in India are more likely than the general population to be illiterate, unemployed and impoverished, but little is known of their HIV risk. 相似文献995.
996.
Weisberg E Kung AL Wright RD Moreno D Catley L Ray A Zawel L Tran M Cools J Gilliland G Mitsiades C McMillin DW Jiang J Hall-Meyers E Griffin JD 《Molecular cancer therapeutics》2007,6(7):1951-1961
Members of the inhibitor of apoptosis protein (IAP) family play a role in mediating apoptosis. Studies suggest that these proteins may be a viable target in leukemia because they have been found to be variably expressed in acute leukemias and are associated with chemosensitivity, chemoresistance, disease progression, remission, and patient survival. Another promising therapeutic target, FLT3, is mutated in about one third of acute myelogenous leukemia (AML) patients; promising results have recently been achieved in clinical trials investigating the effects of the protein tyrosine kinase inhibitor PKC412 on AML patients harboring mutations in the FLT3 protein. Of growing concern, however, is the development of drug resistance resulting from the emergence of point mutations in targeted tyrosine kinases used for treatment of acute leukemia patients. One approach to overriding resistance is to combine structurally unrelated inhibitors and/or inhibitors of different signaling pathways. The proapoptotic IAP inhibitor, LBW242, was shown in proliferation studies done in vitro to enhance the killing of PKC412-sensitive and PKC412-resistant cell lines expressing mutant FLT3 when combined with either PKC412 or standard cytotoxic agents (doxorubicin and Ara-c). In addition, in an in vivo imaging assay using bioluminescence as a measure of tumor burden, a total of 12 male NCr-nude mice were treated for 10 days with p.o. administration of vehicle, LBW242 (50 mg/kg/day), PKC412 (40 mg/kg/day), or a combination of LBW242 and PKC412; the lowest tumor burden was observed in the drug combination group. Finally, the combination of LBW242 and PKC412 was sufficient to override stromal-mediated viability signaling conferring resistance to PKC412. 相似文献
997.
998.
Meja KK Catley MC Cambridge LM Barnes PJ Lum H Newton R Giembycz MA 《The Journal of pharmacology and experimental therapeutics》2004,309(2):833-844
cAMP-elevating drugs are thought to mediate their biological effects by activating the cAMP/cAMP-dependent protein kinase (PKA) cascade. However, this hypothesis is difficult to confirm due to a lack of selective inhibitors. Here, we have probed the role of PKA in mediating inhibitory effects of several cAMP-elevating drugs in BEAS-2B epithelial cells using an adenovirus vector encoding a PKA inhibitor protein (PKIalpha) and have compared it to H-89, a commonly used small molecule PKA inhibitor. Initial studies established efficient gene transfer and confirmed functionality of PKIalpha 48 h after virus infection. All cAMP-elevating drugs tested promoted the phosphorylation of cAMP response element-binding protein (CREB), activated a cAMP response element (CRE)-driven luciferase reporter gene, and suppressed both granulocyte/macrophage colony-stimulating factor (GM-CSF) generation and [(3)H]arachidonic acid (AA) release in response to interleukin-1beta and monocyte chemotactic protein (MCP)-1, respectively. These effects were abolished by PKIalpha. In contrast, H-89 behaved unpredictably under the same conditions. Thus, although CREB phosphorylation evoked by a range of cAMP-elevating drugs was abolished by H-89, neither activation of the CRE-dependent luciferase reporter gene construct nor the inhibition of GM-CSF generation was inhibited. Paradoxically, H-89 antagonized MCP-1-induced [(3)H]AA release and enhanced the inhibitory effect of submaximal concentrations of rolipram and 8-bromo-cAMP. We suggest that expression of PKIalpha in susceptible cells provides a simple and unambiguous way to assess the role of PKA in cAMP signaling and to probe the mechanism of action of other drugs and cAMP-dependent responses where the participation of PKA is equivocal. Furthermore, these data suggest that H-89 is not a selective inhibitor of PKA and should be avoided. 相似文献
999.
C. R. Valeri LCDR MC USNR With the technical assistance of W. M. Booth S. A. Gildea L. E. McCallum 《Transfusion》1968,8(4):210-219
Chromium labelling characteristics of both ACD-stored and previously frozen red cells were evaluated. The chromium uptake of previously frozen red cells processed by agglomeration was inversely related to the hemoglobin level of the suspending fluid. Ascorbic acid was not needed for the labelling of previously frozen, agglomerated red cells.
Cellular injury, as measured by increase in supernatant hemoglobin during post-thaw storage at 4 C, occurred with the agglomerated, previously frozen red cells when: (1) Na2 EDTA was present in the glycerolizing solution; (2) the disaggregation of the agglomerated red cell mass was carried out with 75 rather than 250 ml of isotonic saline; and (3) the storage temperature of the glycerolized red cells was interrupted for one week with a storage interim at either 4 C or −20 C.
By use of a phthalate ester technic, red cells were separated into three fractions on the basis of cellular density. Preferential chromium labelling of red cells was noted: the lightest fraction contained significantly more radioactivity than the heaviest fraction. 相似文献
Cellular injury, as measured by increase in supernatant hemoglobin during post-thaw storage at 4 C, occurred with the agglomerated, previously frozen red cells when: (1) Na
By use of a phthalate ester technic, red cells were separated into three fractions on the basis of cellular density. Preferential chromium labelling of red cells was noted: the lightest fraction contained significantly more radioactivity than the heaviest fraction. 相似文献
1000.
Studies of the cell surface of mouse dendritic cells and other leukocytes 总被引:11,自引:19,他引:11
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MC Nussenzweig RM Steinman JC Unkeless MD Witmer B Gutchinov ZA Cohn 《The Journal of experimental medicine》1981,154(1):168-187
The surface of dendritic cells (DC) has been analyzed by means of monoclonal antibodies (Ab) and lactoperoxidase (LPO)-mediated radioiodination. Antigens and other exteriorily disposed polypeptides of purified spleen DC were compared with those of tissue macrophages (M), monocytes, and other bone marrow-derived elements. Quantitative binding studies and autoradiography with (125)I-Ab established that DC expressed high levels of I-A and H-2D, 2 × 10(5) and 1 × 10(5) Ab binding sites per cell, respectively. DC from conventional, germ-free, and specific pathogen-free mice were all rich in Ia. Expression of Ia on B cells was 5-10 percent of that on DC and increased fivefold during lipopolysaccharide mitogenesis. More than 70-90 percent of purified M and monocytes from specific pathogen-free mice were Ia negative, but increased levels of Ia were noted on cells from mice reared under conventional conditions. Thus large amounts of Ia on DC is a constitutive trait, whereas the expression of Ia by other cell types may be governed by the environmental and immunological status of the host. The 2.4G2 Fc receptor Ag was not detected on DC. Peritoneal and spleen M had 10(5) 2.4G2 binding sites/cell, whereas monocytes and lymphocytes were less reactive (1 × 10(4)-3 × 10(4) binding sites/cell). Four other M-related antigens were evaluated. Each had a distinctive tissue distribution and none bound exclusively to M and monocytes. Neither 1.21J (Mac-1) nor F4/80 reacted with DC. Immunoprecipitation studies of externally ((125)I) and biosynthetically ([(35)S]methionine)dabeled cells confirmed the binding data. Sensitive binding assays with (125)I-Ab confirmed previous observations that DC lack Ig and Thy-1. Lyt-1 was also not found on DC, but 5-12 percent of the cells in purified DC preparations expressed both Lyt-2 and Ia. All DC expressed the leukocyte common antigens at levels similar to other leukocytes. The spectrum of surface polypeptides labeled by LPO-mediated iodination was different on M, DC, and lymphocytes. Polypeptides migrating at molecular weights of 155,000, 85,000, and 62,000 appeared to be restricted to DC. These observations establish that the cell surface of DC differs considerably from other leukocytes, including the blood monocyte, and suggest that the DC is part of a unique Ia-rich leukocyte differentiation pathway. 相似文献