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451.
452.
P-selectin glycoprotein ligand-1 is broadly expressed in cells of myeloid, lymphoid, and dendritic lineage and in some nonhematopoietic cells 总被引:10,自引:3,他引:7
P-selectin glycoprotein ligand-1 (PSGL-1) is a muclin-like glycoportein ligand for P- and E-selectin on myeloid cells and a subset of lymphocytes. We used flow cytometry and immunohistochemistry to examine expression of PSGL-1 on minor leukocyte populations, differentiating hematopoletic cells, and nonhematopoietic tissues using two monoclonal antibodies to distinct protein epitopes on PSGL-1. In the bone marrow, PSGL-1 was expressed on myeloid cells from the myeloblast stage to the segmented neutrophil, but was not detected on erythroblasts or megakaryocytes. All types of circulating myeloid cells expressed PSGL- 1, and PSGL-1 was retained after extravasation of myetoid cells into tissues. PSGL-1 was also expressed on circulating dendritic cells, monocyte-derived dendritic cells, dendritic cells in lymphoid tissues and epidermis, and follicular dendritic cells. All types of lymphoid cells examined expressed PSGK-1, including immature and mature thymocytes, naive and memory T cells, gamma/delta T cells, netural killer cells, B cells and CD34+ progenitor cells. However, PSGL-1 levels were substantially lower on tonsillar lymphocytes than on circulating lymphocytes, suggesting that PSGL-1 expression is down regulated during or after entry of lymphocytes into secondary lymphoid tissue. Although PSGL-1 antigen was detected primarily on hamatopoietic cells, it was also present on time epithelium of the fallopian tube. Furthermore, PSGL-1 antigen gen was detected sporadically on microvascular endothelium in some pathologic tissues. This suggests that PSGL-1 may have functions other than mediating leukocyte adhersion. 相似文献
453.
454.
Histone deacetylase-1 and -3 protein expression in human breast cancer: a tissue microarray analysis
Krusche CA Wülfing P Kersting C Vloet A Böcker W Kiesel L Beier HM Alfer J 《Breast cancer research and treatment》2005,90(1):15-23
Summary Impaired histone acetylation was recognized to be involved in carcinogenesis. Furthermore, histone deacetylase (HDAC) inhibitors induce differentiation of breast cancer cells and inhibit tumour growth. These results prompted us to study HDAC-1 and -3 expression in breast tumours to establish their potential therapeutic and prognostic significance.HDAC-1 und HDAC-3 protein expression was analyzed immunohistochemically on a tissue microarray (TMA) containing 600 core biopsies from 200 patients. HDAC-1 and -3 expression was correlated to steroid hormone receptor-, Her2/neu- and proliferation status of tumours as well as to overall and disease free survival.Moderate or strong nuclear immunoreactivity for HDAC-1 was observed in 39.8% and for HDAC-3 in 43.9% of breast carcinomas. HDAC-1 and -3 expression correlated significantly with oestrogen and progesterone receptor expression (both p< 0.001). HDAC-1 expression predicted significantly better disease free survival (DFS: p=0.044), in particular, in patients with small tumours of all differentiation types (DFS: p=0.016). Multivariate analysis demonstrated that HDAC-1 is an independent prognostic marker.Our data suggest that evaluation of HDAC-1 protein expression enables a more precise assessment of the prognosis of breast cancer patients. Thus, HDAC-1 expression analysis might be clinically useful to facilitate an individual, risk-directed, adjuvant systemic therapy in breast cancer patients. 相似文献
455.
JKS Parihar SM RP Gupta PK Sahoo RP Misra DP Vats SM VSM AP Kamath FEA Rodrigues 《Medical Journal Armed Forces India》2005,61(2):139-142
Background
To evaluate and compare efficacy and outcome after single site phacotrabeculectomy and conventional combined surgery in cases of coexisting primary open angle glaucoma and cataract.Methods
This prospective study on fifty patients of concurrent primary open angle glaucoma and cataract, who had undergone combined surgery as single site phacotrabeculectomy or conventional single site trabeculectomy with extracapsular lens extraction with IOL implantation in 25 cases each. Evaluation was based on operative and postoperative complications, control of IOP and visual outcome. The follow up period ranged between twelve months to eighteen months.Results
The mean medically controlled preoperative intraocular pressure was 22 mm of Hg (Range 18 to 35 mm of Hg) by applanation method of tonometry. The range of postoperative intra-ocular pressure after one year was 11 to 22 mm of Hg in first and 14 to 26 mm Hg in second group. Failure to maintain optimum postoperative IOP without Beta-blocker was more frequent after conventional combined procedure. There was no significant difference in incidence and pattern of postoperative complications.Conclusion
Phacotrabeculectomy provides effective and sustained visual recovery and adequate control of intraocular pressure as compare to conventional combined procedure.Key Words: Phacotrabeculectomy, Comparison with conventional combined procedure 相似文献456.
A fluoroscopically guided anterior approach to celiac plexus block was developed that can be performed on the supine patient during a percutaneous biliary procedure. Unlike posterior blocks, anterior blocks can be performed at any time during the procedure and thus can be reserved for the few patients whose pain does not respond to intravenously administered narcotics. Anterior blocks were performed 18 times in 14 patients; satisfactory visceral anesthesia was achieved in ten of the 18 procedures. 相似文献
457.
Lipid peroxidation in stored red cells 总被引:1,自引:0,他引:1
Lipid peroxidation is initiated by the production of oxygen-free radicals; it is increased in a wide variety of diseases, including various hemolytic anemias, and in hemoglobin disorders. Increased lipid peroxidation occurs in red cells in the presence of reactive iron species and some heme moieties. In this study, greatly reduced concentrations of malondialdehyde, an indicator of lipid peroxidation, were observed in stored blood upon the addition of both deferoxamine mesylate and diethylenetriaminepentaacetic acid (p less than 0.001). The antioxidant glutathione was much less effective (p less than 0.01 or less than 0.05, depending on incubation time). On the other hand, the addition of dimercaptosuccinic acid and ascorbic acid both significantly increased malondialdehyde production over controls (p less than 0.001 and p less than 0.05, respectively). Ascorbic acid, in the presence of deferoxamine mesylate, added no red cell protection over that of deferoxamine mesylate alone. The addition of metal chelators and, possibly, certain antioxidants to stored blood may be effective in increasing the viability and longevity of transfused red cells. 相似文献
458.
459.
Modulated expression of notch1 during thymocyte development 总被引:9,自引:2,他引:7
The Notch gene family encodes transmembrane proteins that have been implicated in control of diverse cellular differentiation events in the fly, frog, and mouse. Mammalian Notch1 is expressed at high levels in thymus and is mutated in a subset of human T-cell acute lymphoblastic neoplasms, suggesting a role in T-cell differentiation. To investigate the patterns of expression of NOTCH1 protein in thymocytes of the developing and mature thymus, antibodies raised against NOTCH1 were used to perform immunohistochemical and flow cytometric analyses. Strong staining for NOTCH1 within the fetal murine thymus was observed as early as 13.5 days postcoitum. By 17.5 days postcoitum, preferential staining of superficial cortical thymocytes was observed, with weak staining of developing medulla. Flow cytometric analysis and immunohistochemical staining of flow-sorted cells confirmed that the highest levels of NOTCH1 expression in adult murine thymus were present in immature cortical thymocytes (CD24high, CD4-CD8-). In contrast, NOTCH1 expression was low or absent in more mature cortical thymocytes (CD24low, CD4+CD8+), whereas intermediate levels of expression were observed in CD4+CD8- and CD4-CD8+ cells. These data indicate a dynamic pattern of NOTCH1 expression during T-cell differentiation and suggest that downregulation of NOTCH1 may be required for maturation of cortical thymocytes. 相似文献
460.
Angiographic findings in 61 stab wounds to the neck were correlated with specific clinical findings. Eighteen of the stab wounds were associated with one or more major physical findings that included (a) pulse deficit, (b) active bleeding or expanding hematoma, (c) bruit or murmur, (d) neurologic deficit, or (e) hypotension. Of these 18 wounds, only two involved significant vascular injuries. The other 43 stab wounds were associated with minor physical findings, with the only indications for angiography being nonexpanding hematoma or proximity of trauma to major vessels. None of these 43 wounds involved significant vascular injury. 相似文献