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941.
Lambolez F Azogui O Joret AM Garcia C von Boehmer H Di Santo J Ezine S Rocha B 《The Journal of experimental medicine》2002,195(4):437-449
Gut intraepithelial CD8 T lymphocytes (T-IEL) are distinct from thymus-derived cells and are thought to derive locally from cryptopatch (CP) precursors. The intermediate stages of differentiation between CP and mature T-IEL were not identified, and the local differentiation process was not characterized. We identified and characterized six phenotypically distinct lineage-negative populations in the CP and the gut epithelium: (a) we determined the kinetics of their generation from bone marrow precursors; (b) we quantified CD3-epsilon, recombination activating gene (Rag)-1, and pre-Talpha mRNAs expression at single cell level; (c) we characterized TCR-beta, -gamma, and -alpha locus rearrangements; and (d) we studied the impact of different mutations on the local differentiation. These data allowed us to establish a sequence of T cell precursor differentiation in the gut. We also observed that the gut differentiation varied from that of the thymus by a very low frequency of pre-Talpha chain mRNA expression, a different kinetics of Rag-1 mRNA expression, and a much higher impact of CD3 epsilon/delta and pre-Talpha deficiencies. Finally, only 3% of CP cells were clearly involved in T cell differentiation, suggesting that these structures may have additional physiological roles in the gut. 相似文献
942.
We tested the ability of several social-cognitive models to predict intentions to engage in two different health behaviors (resisting dieting and performing breast self-exam). All constructs from the health belief model (with and without self-efficacy), the theory of planned behavior (with and without perceived behavioral control) and the motivational process of the health action process approach were measured simultaneously in two subject samples. We hypothesized that models that include self-efficacy (or the related construct of perceived behavioral control) would be more effective than the models that do not include it. Our results supported this prediction. The health action process approach was the best predictor of intentions to engage in both behaviors. Implications for selecting appropriate models on which to base interventions are discussed. 相似文献
943.
Biondi C Cotorruelo C Garcia Borrás S Rocca L Ensinck A Marini A Racca A 《Clinical and experimental medicine》2003,2(4):197-198
There is a decrease in the percentage contribution of a heavy density fraction of red blood cells to whole blood with increasing
age. The aim of this study was to investigate in the young and elderly the interaction between monocytes and different erythrocyte
suspensions: senescent red blood cells, erythrocytes stored with or without serum, and desialylated red blood cells. The results
obtained with senescent red blood cells and erythrocytes stored with serum show the involvement of autologous IgG in the selective
removal of erythrocytes. These values were higher in elderly individuals, indicating that this process increases with age.
Our observation suggest that desialylation is not involved in the increased removal of erythrocytes observed in elderly individuals.
Received: 3 October 2002 / Accepted: 11 December 2002
Correspondence to C. Biondi 相似文献
944.
OBJECTIVE: To analyze the long-term clinical outcome of dedifferentiated chondrosarcoma or chondrosarcoma with additional malignant mesenchymal component (CAMMC) of the larynx and compare the results with those of axial chondrosarcomas. STUDY DESIGN/METHODS: Two patients with CAMMC of the larynx (0.03%) were retrospectively identified within the archives of the Armed Forces Institute of Pathology between 1970 and 2001. We compared the clinical and histologic features of these two cases with those reported in the English literature (Medline 1966-2001) (Table I). RESULTS: Patient no. 1 was a 67-year-old man who presented with a 12-month history of hoarseness and was found to have a 4-cm mass involving the cricoid cartilage. Enucleation was performed and histologically demonstrated a dedifferentiated chondrosarcoma. Without additional intervention, the patient died after 136 months without evidence of disease. Patient no. 2 was a 41-year-old man who also presented with a 12-month history of hoarseness and dysphagia and was found to have a 5-cm mass involving the cricoid cartilage. A total laryngectomy was performed for the dedifferentiated chondrosarcoma. He is alive without evidence of disease at last contact (91 mo). CONCLUSION: CAMMC of the larynx are rare tumors but have a better prognosis than their axial counterparts (mean, 6 mo). Initial voice-sparing surgery can be followed with more aggressive surgery if recurrences develop. 相似文献
945.
946.
Ganzarolli SM Rached RN Garcia RC Del Bel Cury AA 《Journal of oral rehabilitation》2002,29(8):787-790
Well-fitted dentures prevent hyperplasic lesions, provide chewing efficiency and promote patient's comfort. Several factors may affect final adaptation of dentures, as the type of the acrylic resin, the flask cooling procedure and the water uptake. This investigation evaluated the effect of water storage and two different cooling procedures [bench cooling (BC) for 2 h; running water (RW) at 20 degrees C for 45 min] on the final adaptation of denture bases. A heat-cured acrylic resin (CL, Clássico, Clássico Artigos Odontológicos) and two microwave-cured acrylic resins [Acron MC, (AC) GC Dent. Ind. Corp.; Onda Cryl (OC), Clássico Artigos Odontológicos] were used to make the bases. Adaptation was assessed by measuring the weight of an intervening layer of silicone impression material between the base and the master die. Data was submitted to ANOVA and Tukey's test (0.05). The following means were found: (BC) CL=0.72 +/- 0.03 a; AC=0.70 +/- 0.03 b; OC=0.76 +/- 0.04 c//(RW) CL= 1.00 +/- 0.11 a; AC=1.00 +/- 0.12 a; OC=0.95 +/- 0.10 a. Different labels join groups that are not statistically different (P > 0.05). Comparisons are made among groups submitted to the same cooling procedure (BC or RW). The conclusions are: interaction of type of material and cooling procedure had a statistically significant effect on the final adaptation of the denture bases (P < 0.05); water storage was not detected as a source of variance (P > 0.05) on the final adaptation. 相似文献
947.
948.
Wang H Hosiawa KA Garcia B Shum JB Dutartre P Kelvin DJ Zhong R 《Xenotransplantation》2003,10(4):325-336
Searching for a novel immunosuppressive agent to effectively prevent acute vascular rejection (AVR) is essential for success in clinical xenotransplantation. We previously reported that Lewis rat hearts transplanted into BALB/c mice developed typical AVR in 6 days. The present study was undertaken to determine the efficacy of LF 15-0195, a new immunosuppressive analog of 15-deoxyspergualin in the prevention of AVR in a rat-to-mouse cardiac xenograft model. We transplanted 2-week old Lewis rat hearts into BALB/c mice. Four groups were included in this study: untreated recipients and cyclosporin A (CsA) treated recipients were controls; LF 15-0195 treated recipients or LF 15-0195 combined with CsA treated recipients were experimental groups. Mouse recipients received either LF 15-0195 2 mg/kg subcutaneously from day-1 to post-operative day 14, or CsA 15 mg/kg subcutaneously daily, from day 0 to endpoint rejection, or the two drugs in combination. We observed that high dose CsA did not inhibit AVR and the graft was rejected in 11.3 +/- 1.9 days. Graft histology and immunohistology showed typical AVR, characterized by interstitial hemorrhage, intravascular fibrin deposition, thrombosis, and massive deposition of anti-rat immunoglobulin G (IgG) and immunoglobulin M (IgM). Serum xenoreactive antibodies (xAbs) were markedly elevated in these animals as well. In contrast, we observed that treatment with LF 15-0195 alone significantly prolonged graft survival to 19.3 +/- 0.7 days. Notably, xAbs were significantly decreased and the rejection pattern of these grafts was cell-mediated rejection (CMR), instead of AVR. When CsA was combined with LF 15-0195, the graft mean survival time was further increased to 58.5 +/- 17.3 days. Antibody production and T-cell infiltration were significantly inhibited at the terminal stages of graft survival and pathology showed striking attenuation of both AVR and CMR. Sequential studies on days 6 and 14 demonstrated that LF 15-0195 either alone or combined with CsA completely inhibited antibody production. However, intragraft infiltration by Mac-1 positive cells including natural killer cells, macrophages and granulocytes in LF 15-0195 treated recipients was similar to that of untreated recipients. We conclude that LF 15-0195 effectively prevented AVR by markedly inhibiting the production of anti-donor IgG xAbs. Also, treatment with short course LF 15-0195 and continuous CsA significantly reduced T-cell infiltration. Studies to test this therapy in inhibiting AVR in a pig-to-non-human primate xenotransplantation model are underway. 相似文献
949.
The purpose of this article was to document the efforts of two military installations in facilitating Critical Incident Stress Management teams for Federal Emergency Management Agency Rescue and Recovery Units following the attacks on the World Trade Center on September 11, 2001. McGuire Air Force Base accepted the mission to support the rotating task forces with emotional support, and Fort Dix offered temporary lodging while the teams were in-bound and out-bound to the "Ground Zero" site. A team, comprised of staff from both installations due to the configuration of professional and support staffs, does the Critical Incident Stress Management work. Both installations are within commuting distance of New York City and could provide adequate safety, security, and logistics to the teams. The classic crisis management models were not called into play, as that service was not asked for; however, it was clear to the McGuire Air Force Base/Fort Dix Critical Incident Stress Management team members that the rescue and recovery teams needed their physical presence. Many rescue organizations have their own "debriefing teams," yet it is believed that "outside teams" may be helpful as interim measures to demonstrate the universality of the process of coping with traumatic stress and grief management. It is hoped that this article honors the workers who came together to help in a very difficult time for our country. This article documents the interim measures that were taken for a group of people moving through crisis. 相似文献
950.
Portal vein thrombosis: an emergency solution for blood flow in liver transplantation 总被引:1,自引:0,他引:1
Angel?Bernardos Juan?SerranoEmail author Miguel?A.?Gomez Inmaculada?Garcia Maria?Jesús?Tamayo Felipe?Pareja Concepción?Diaz Cristobalina?Martín 《Transplant international》2003,16(8):598-599
Recipient portal vein thrombosis in liver transplantation is a contingency that increases surgical difficulty as well as patient morbidity and mortality. The aim of this paper is to demonstrate a surgical technique for reconstruction of portal blood flow in emergency situations of portal vein thrombosis with inadequate blood flow and a poor vascular bed for re-vascularization. 相似文献