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排序方式: 共有1693条查询结果,搜索用时 15 毫秒
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A male, full-term baby with thrombocytopenia was born by a G3P2A1 mother who was not associated with autoimmune disease. Platelet antibody screening was positive by using lymphocytotoxicity test, platelet suspension immunofluorescence test and solid-phase red cell adherence test. The identified HLA antibody was of A2 specificity. It was confirmed by testing the mother's and the baby's sera against the lymphocytes and platelets of 10 HLA-A2-positive donors. The possibility of platelet-specific antibody as the cause of neonatal alloimmune thrombocytopenia was ruled out by testing against platelets of 10 HLA-A2-negative donors and the known platelet-specific antigens utilizing immobilized, purified platelet glycoprotein as targets. The mother's serum reacted strongly with both the father's and the baby's platelets and lymphocytes. This neonatal thrombocytopenia was most likely due to the maternal HLA antibody, which was induced by her antecedent gestations. 相似文献
3.
Yang-Sheng Tzeng Eric Hoffman Janice Cook-Granroth Rie Maurer Niral Shah Joey Mansour Juerg Tschirren Mitchell Albert 《Magnetic resonance in medicine》2007,58(3):636-642
An anthropomorphic airway tree phantom was imaged with both hyperpolarized (HP) 3He MRI using a dynamic projection scan and computed tomography (CT). Airway diameter measurements from the HP 3He MR images obtained using a newly developed model-based algorithm were compared against their corresponding CT values quantified with a well-established method. Of the 45 airway segments that could be evaluated with CT, only 14 airway segments (31%) could be evaluated using HP 3He MRI. No airway segments smaller than approximately 4 mm in diameter and distal to the fourth generation were adequate for analysis in MRI. For the 14 airway segments measured, only two airway segments yielded a non-equivalent comparison between the two imaging modalities, while eight more had inconclusive comparison results, leaving only four airway segments (29%) that satisfied the designed equivalence criteria. Some of the potential problems in airway diameter quantification described in the formulation of the model-based algorithm were observed in this study. These results suggest that dynamic projection HP 3He MRI may have limited utility for measuring airway segment diameters, particularly those of the central airways. 相似文献
4.
高脂血症患者C—反应蛋白含量的变化及氟伐他汀对它的影响 总被引:4,自引:1,他引:3
Dong-Sheng Chi Feng-Xia Jin Shu-Guang Yang Yu-Wen Su Bin Ge Jie Zhang Yan Zhang Yi-Li Liu 《第一军医大学学报》2002,22(12):1109-1111
OBJECTIVE: To observe the changes of C-reactive protein (CRP) level and its relationship with blood lipids, and the effects of fluvastatin on CRP and the lipids in patients with hyperlipidemia. METHODS: Serum levels of cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), very-low-density lipoprotein cholesterol (VLDL-C) and lipoprotein(a)[Lp(a)] were measured by enzyme assay, and plasma CRP level by immunonephelometry before and after fluvastatin treatment (20 mg/d for 4 weeks) in patients with hyperlipidemia. RESULTS: CRP levels were above normal in 90.3% hyperlipidemia cases in spite of the various accompanying diseases. Fluvastatin treatment significantly reduced TC (-7.49%), TG (-14.32%), LDL (-13.88%), VLDL (-18.48%) and TC/HDL(-13.50%) levels (P<0.01), and also brought down Lp(a) concentration (-13.81%). CRP levels was very effectively reduced after the treatment (-15.92%, P<0.001). No association between basal CRP levels and basal lipids and Lp(a) concentrations was observed. Positive correlation of CRP, however, was observed after fluvastatin treatment with TC/HDL (r=0.62, P=0.041) and Lp(a) (r=0.320, P=0.011), while inverse relations were noted between CRP and HDL (r=-0.288, P=0.023). CONCLUSION: CRP levels increases markedly in patients with hyperlipidemia, a fact that is independent of the accompanying diseases. In addition to modulating blood lipid levels, fluvastatin also reduces CRP level, the latter possibly serving as an independent predictive factor for atherosclerotic cardiovascular diseases and also as an indicator for estimating the effectiveness of the treatment. 相似文献
5.
Wang M Tzeng TY Fung CY Ou WC Tsai RT Lin CK Tsay GJ Chang D 《Journal of virological methods》1999,78(1-2):171-176
The immunoreactivity of human anti-JC virus (JCV) serum against the major capsid protein VP1 of JCV was analyzed by Western blot, dot blot, and hemagglutination inhibition (HAI) assays. JCV-positive human serum reacted with native but not denatured JCV major capsid protein VP1, as demonstrated by dot blot and Western blot. Rabbit antiserum raised against native JCV capsid had immunoreactivities similar to those of human anti-JCV serum. These results indicate that the antigenecity of native and denatured JCV VP1 is different. In addition, both JCV-positive human serum and rabbit antiserum raised against native JCV capsid protein inhibited the hemagglutination activity of JCV capsid particles. In contrast, rabbit antiserum raised against denatured JCV VP1 did not inhibit hemagglutination. These findings reveal that denaturation may alter the antigenic epitopes of JCV VP1. Therefore, keeping the JCV capsid protein native appears to be essential for serological or other immunological analyses of the virus. 相似文献
6.
Transcriptome analysis in blastocyst hatching by cDNA microarray 总被引:1,自引:0,他引:1
Chen HW Chen JJ Yu SL Li HN Yang PC Su CM Au HK Chang CW Chien LW Chen CS Tzeng CR 《Human reproduction (Oxford, England)》2005,20(9):2492-2501
BACKGROUND: Hatching is an important process for early embryo development, differentiation and implantation. However, little is known about its regulatory mechanisms. By integrating the technologies of RNA amplification and cDNA microarrays, it has become possible to study the gene expression profile at this critical stage. METHODS: Pre-hatched and hatched ICR mouse embryos (25 blastocysts in each group were used in the triplicate experiments) were collected for RNA extraction, amplification, and microarray analysis (the mouse cDNA microarray, 6144 genes, including expressed sequence tags). RESULTS: According to cDNA microarray data, we have identified 85 genes that were expressed at a higher level in hatched blastocyst than in pre-hatched blastocysts. In this study, 47 hatching-related candidate genes were verified via re-sequencing. Some of these genes have been selected and confirmed by real-time quantitative RT-PCR. These hatching-specific genes were also expressed at a lower level in the delayed growth embryos (morula or blastocyst without hatching at day 6 post hCG). These genes included: cell adhesion and migration molecules [E-cadherin, neuronal cell adhesion molecule (NCAM), lectin, galactose binding, soluble 7 (Lgals7), vanin 3 and biglycan], epigenetic regulators (Dnmt1, and SIN3 yeast homolog A), stress response regulators (heme oxygenase 1) and immunoresponse regulators [interleukin (IL)-2-inducible T-cell kinase, IL-4R, interferon-gamma receptor 2, and neurotrophin]. The immunostaining of E-cadherin and NCAM showed strong and specific localization in hatched blastocyst. CONCLUSIONS: This work provides important information for studying the mechanisms of blastocyst hatching and implantation. These hatching-specific genes may have potential as new drug targets for controlling fertility. 相似文献
7.
The aim of this study was to compare the differential sensitivities of B16 melanoma sublines to LAK cells by means of the standard 51Cr release assay and a clonogenic assay, which measures both cell survival and proliferation. LAK cells, generated after 4 days incubation with 150 international units (IU)/ml of interleukin-2 (IL-2), showed both cytolytic and anti-proliferative activities against B16 targets. Using an 18 h 51Cr release assay, murine LAK cells showed the highest cytolytic activity against B16 parental cells compared to B16-F1, B16-F10, B16-FLR and B16-BL6 sublines at effector/target (E/T) ratios ranging from 6/1 to 100/1. Purified adherent LAK (A-LAK) cells showed greater cytolytic activity against B16 parental cells and other B16 sublines compared to LAK cells, but otherwise the pattern of reactivity was similar. Using a clonogenic assay, the surviving fraction of B16 parental cells co-cultivated with LAK cells decreased to 0 at an E/T ratio of 50/1, while a 400/1 ratio was required to achieve a similar reduction of B16-F1, B16-F10, B16-FLR, and B16-BL6 sublines. No differences in subline sensitivity were seen with the 51Cr release assay, but these were observed using the clonogenic assay. An inverse linear relationship existed between % surviving fraction, as determined by the clonogenic assay, and cytolytic activity, as determined by the 51Cr release assay. Our data indicate that the clonogenic assay can detect differences in target cell sensitivity that otherwise are undetectable by the standard 51Cr release assay. The clonogenic assay may prove useful in delineating the long-term anti-adherent and anti-proliferative properties of effector cells from their cytolytic activity. 相似文献
8.
Hyperalgesia and neural excitability following injuries to central and peripheral branches of axons and somata of dorsal root ganglion neurons 总被引:7,自引:0,他引:7
We examined thermal hyperalgesia, excitability of dorsal root ganglion (DRG) neurons, and antinociceptive effects of N-methyl-d-aspartate (NMDA) receptor antagonists in rats with injury to different regions of DRG neurons. The central or peripheral branches of axons of DRG neurons were injured by partial dorsal rhizotomy (PDR) and chronic constriction injury of sciatic nerve (CCI), respectively, or the somata injured by chronic compression of DRG (CCD). Thermal hyperalgesia was evidenced by significantly shortened latencies of foot withdrawal to radiant heat stimulation of the plantar surface. Intracellular recordings were obtained in vitro from L(4) and/or L(5) ganglia. There are four principle findings: 1) PDR as well as CCD and CCI induced thermal hyperalgesia; 2) PDR produced significantly less severe and shorter duration hyperalgesia than CCD and CCI; 3) intrathecal administration of NMDA receptor antagonists d-2-amino-5-phosphonovaleric acid (APV) and dizocilpine maleate (MK-801) inhibited thermal hyperalgesia in PDR, CCD, and CCI rats. Pretreatment of APV and MK-801 delayed the emergence of hyperalgesia for 48-72 h, while posttreatment inhibited hyperalgesia for 24-36 h; and 4) CCD and CCI increased excitability of DRG neurons as judged by the significantly lowered threshold currents and action potential voltage thresholds and increased incidence of repetitive discharges. However, PDR did not alter the excitability of DRG neurons. These findings indicate that injury to the dorsal root, compared with injury to the peripheral nerve or DRG somata has different effects on the development of hyperalgesia. These contributions involve different changes in DRG membrane excitability, but each involves pathways (presumably in the spinal cord) that depend on NMDA receptors. 相似文献
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10.
J Y Cheng C L Meng J C Lin C C Tzeng L T Chin K L Shen 《Journal of surgical oncology》1990,44(4):260-267
Four colon adenocarcinoma cell lines, CC-M2, CC-M3, CC-M4, and CC-M2NM, have been established from surgical specimens of 18 unselected patients without the use of "feeder" cells and additional growth factors (e.g., insulin, hydrocortisone, etc.) in the culture medium. The methods of primary cultivation of tissue explants are described. Studies of determination of morphology, growth curve, plating efficiency, chromosomal analysis, CEA and beta-HCG synthesis, and tumorigenicity, were done to characterize the cell lines. Significant variations have been found in one of the four cell lines, both in vitro and in vivo studies. There are distinct phenotypes in the established cell lines which may be useful in studying the cell differentiation and progression of colorectal cancer. 相似文献