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741.
A distinct profile of six soluble adhesion molecules (ICAM-1, ICAM-3, VCAM-1, E-selectin, L-selectin and P-selectin) in rheumatoid arthritis 总被引:10,自引:1,他引:10
Littler AJ; Buckley CD; Wordsworth P; Collins I; Martinson J; Simmons DL 《Rheumatology (Oxford, England)》1997,36(2):164-169
Soluble forms of ICAM-1, VCAM-1, E-selectin, L-selectin, P-selectin and,
more recently, ICAM-3 are known to exist in human serum and have elevated
levels in numerous diseases. Previous studies have demonstrated that in
rheumatoid arthritis (RA) the levels of circulating sICAM-1 and sE-selectin
are elevated relative to healthy controls. We have compared the serum
profiles of these six soluble adhesion molecules in patients with RA (n =
22) to those seen in healthy controls (n = 10) using sandwich ELISA. In the
patients, there were significant elevations of serum sICAM-1 (P <
0.0001), sICAM-3 (P = 0.0327), sVCAM-1 (P = 0.0025), sL-selectin (P =
0.0194) and sP-selectin (P = 0.0025), but not E-selectin (P = 0.0672).
However, only sP- selectin was found to correlate with disease activity in
the patients (r = 0.461, P < 0.05). Thus, there is a distinct profile of
soluble adhesion molecules in RA of which only sP-selectin correlates with
disease activity.
相似文献
742.
The mechanism by which influenza virus interferes with polymorphonuclear leukocyte (PMN) chemotaxis was investigated. Incubation of human PMN with influenza A virus in vitro for 30 minutes significantly decreased PMN migration under agarose in response to N- formyl-methionyl-leucyl-phenylalanine (FMLP) or zymosan-activated serum. Virus-treated PMN tended to aggregate in the under-agarose assay. Aggregation was avoided by using a more dilute PMN suspension in filter assays. Virus treatment significantly decreased migration through 100-micron thick cellulose nitrate filters but had no effect on migration through 10-micron thick polycarbonate filters or on PMN bipolar shape change. Virus was not chemotactic in the polycarbonate filter assay and did not induce shape change in purified PMN. It was concluded that influenza virus did not interfere with the ability of PMN to recognize a chemoattractant, undergo shape change, and move a short distance but did limit the extent of migration. Inhibition could not be explained by chemotactic deactivation, since the virus was not chemotactic. 相似文献
743.
744.
745.
Preferentially expressed genes in chronic myelogenous leukemia 总被引:1,自引:0,他引:1
The predominant circulating cells in chronic myelogenous leukemia (CML) morphologically resemble normal myeloid precursors; however, certain characteristics indicate the two are not identical. Approximately 88% of the patients with clinically typical CML present with a cytogenetic abnormality known as the Philadelphia chromosome (Ph1). Additionally, the leukocyte alkaline phosphatase (LAP) value is decreased in CML. To investigate if there are selected genes expressed in the CML cell population, poly(A+)RNA from a chronic-phase, Ph1-positive CML patient was used for construction of a complementary DNA (cDNA) library. Recombinant clones representing moderately to abundantly transcribed sequences were selected by annealing [32P]-cDNA transcribed from homologous RNA to the library sequences and assessing radioactivity in the hybrids. From an initial 729 colonies, 417 (57.2%) displayed a hybridization signal more intense than controls, indicating these recombinant plasmids contained sequences homologous to moderately or highly expressed RNAs from this particular patient. Screening of the 417 clones--utilizing 32P-cDNAs derived from normal human placenta, an acute myelomonocytic leukemia (AMML), and two other CML samples--was used to select clones likely to represent sequences preferentially expressed in CML. Sixteen recombinants were initially selected that repeatedly failed to display hybridization with the placenta and AMML- derived probes. Further analysis of eight of these clones indicated that six contain sequences preferentially expressed in CML. One clone, C-A3, has been studied with 63 different RNA samples. This sequence is found to be highly expressed in peripheral blood cells from the chronic phase of both Ph1-positive and Ph1-negative CML as well as in a Ph1- positive acute myelogenous leukemia (AML). Expression is reduced in lymphoblastic crisis of CML (L BC-CML) and essentially absent in myeloblastic crisis of CML (M BC-CML). While preliminary, the results suggest that this probe may be useful as an aid in diagnosing Ph1- negative CML and in distinguishing M BC-CML from L BC-CML and Ph1- positive AML. 相似文献
746.
Distal ureteral calculi: detection with vaginal US 总被引:2,自引:0,他引:2
747.
A strain of Lipomyces kononenkoae earlier proposed for industrial starch bioconversion was found to have a dissociative temperature profile. The ARRHENIUS plot of sustained exponential growth displayed a single branch between the optimum (32–33°C) and the maximum (about 35°C) temperature for growth while the extrapolated ARRHENIUS plots of growth and thermal death intersected at a biologically non-significant value. The yield of L. kononenkoae on glucose did not decrease at supraoptimal temperatures while the associative yeast Saccharomyces cerevisiae suffered yield decreases above the optimum temperature for growth with increasing temperature. 相似文献