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1.
Pierre Robin sequence (PRS) describes a small mandible with retrognathia, an elevated and posteriorly positioned tongue, and an associated U-shaped cleft palate. The retracted tongue may obstruct the airway leading to respiratory failure, with failure to thrive and adverse neurodevelopmental outcomes if not addressed. If the airway obstruction cannot be overcome with conservative measures, there are non-surgical and surgical options. A nasopharyngeal prong (NPP) is a non-surgical, temporary treatment that avoids the complications inherent in an operation, especially given the natural history of mandibular growth and improved airway obstruction in PRS. Although the use of a prong requires training, support, and follow up, it effectively bypasses the obstruction in the majority of children with PRS, and allows the child to outgrow the airway obstruction until the prong is no longer required. On average, the prong can be removed between 6 and 12 months of age.  相似文献   
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口咽鳞癌的临床处理仍存在争议,该文对口咽癌患者应用原发灶手术切除、颈淋巴清扫及术后行放疗的效果进行总结。对复合标准的211例患者进行回顾性研究。应用Kaplan—Meier曲线计算总生存率及无瘤生存率,应用单变量及多变量统计学分析研究疾病的临床特点与预后的关系。2年及5年的无瘤生存率分别为79.8%和68.8%.单因素分析表明,肿瘤切缘阳性是无瘤生存率重要也是唯一的预后因素。  相似文献   
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A 7-year-old, 17-kg child with chronic granulomatous disease and nocardial pneumonia and osteomyelitis did not respond to antibiotic therapy and developed multiple red cell (RBC) alloantibodies (anti-c, -E, and -Jka). To provide daily granulocyte concentrates, a method was devised to reduce the number of incompatible RBCs per transfusion. Leukapheresis was done with hydroxyethyl starch, and the apheresis product was allowed to sediment by gravity in a plasma expressor for 90 minutes. The leukocyte-rich plasma was separated from the sedimented RBCs by transfer to a satellite bag, and the volume of the product was reduced by centrifugation to approximately 80 ml. RBC content was reduced from 29 +/- 7 to 2.5 +/- 1.0 ml (n = 22, p less than 0.01) and was accompanied by a 70 percent recovery of white cells (range, 49-90%). The final product contained 1.6 +/- 1.0 X 10(10) granulocytes. There were no clinical or laboratory signs of hemolysis during the course of 46 granulocyte transfusions, 37 of which were derived from c-, E-, or Jka-positive donors. The size of most apheresis donor pools is insufficient to provide phenotypically matched granulocyte concentrates daily for patients with RBC alloimmunization. The rapid, simple method described here may allow daily therapy with mismatched concentrates to be administered safely to such patients.  相似文献   
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Small instestinal submucosa (SIS) is an easily produced material that has been used experimentally for tissue engineering. To evaluate the ability of SIS to facilitate bone growth within a long-bone defect, a segment of the radius was surgically removed in adult, female Sprague-Dawley rats. The defect was either left unfilled or implanted with SIS, demineralized cortical bone (DMCB), or ovalbumin. The defect was evaluated radiographically and histologically after 3, 6, 12, and 24 weeks. Tissue remodeling within the defect was evident by week 3 in SIS- and DMCB-treated rats. Filling was characterized initially by infiltration of mononuclear cells and extracellular material in SIS-implanted rats and multifocal remodeling bone particles and cartilage formation in DMCB implanted rats. Cartilage was observed as early as 3 weeks and bone as early as 6 weeks in SIS-implanted rats. Filling of the defect arose from multiple foci in DMCB-implanted rats, but was contiguous with and parallel to the ulnar shaft in SIS-implanted rats, suggesting that defect repair by SIS may be conductive rather than inductive. Rats in which the defect was left unfilled demonstrated slow but progressive filling of the defect, characterized by mononuclear cell infiltrates and fibrous extracellular material. In summary, SIS facilitated rapid filling of a longbone defect. These results suggest that SIS may be useful as a bone repair material.  相似文献   
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目的:采用定量分析方法比较体育与非体育专业大学生静态平衡能力,分析运动及性别对大学生静态平衡功能的影响。方法:于2007-01/03选取首都体育学院在校大学生共78名为受试对象,其中体育(武术)专业学生40名,非体育(康复)专业学生38名。所有选取对象了解试验目的,并同意参与本实验。采用意大利PosturalEqua平静分析系统,对实验对象分别在睁眼60s、闭眼60s两种状态下测试其静态平衡的各项指标,包括压力中心,线形图总长度,最大摆幅,线形图面积,LFS指数,压力分布,稳定性图及隆伯格值。结果:78名为受试对象均进入结果分析。①两专业学生压力中心X轴短于Y轴、压力分布前(%)高于后(%)(P<0.01)。②在闭眼状态下,体育专业男大学生在指标LFS指数和额状面上大于非体育专业(P<0.05)。③非体育业大学生在睁眼状态下,Y值女性小于男性,额状面值女性大于男性。男、女生睁闭眼差值进行比较时,女性在线形图总长度、额状面和LFT指数均大于男性(P<0.01),而线形图面积小于男性(P<0.05)。④体育专业大学生在睁眼状态下,指标参数Y值女性小于男性,额状面值女性大于男性;闭眼状态下,指标参数Y值女性小于男性,额状面值和LFS值女性大于男性。男、女生睁闭眼差值比较,女性在线形图总长度、额状面和LFT指数均大于男性(P<0.05,P<0.01),而线形图面积小于男性(P<0.05)。结论:①运动训练对大学生静态平衡影响不大,但对男性大学生的某些平衡指标却有显著影响。②性别对大学生的静态平衡均产生影响,表现为男性平衡的微控制能力优于女性。  相似文献   
7.
The effect of prestorage irradiation on posttransfusion red cell survival   总被引:1,自引:0,他引:1  
Transfusion-associated graft-versus-host disease (TA-GVHD) may occur whenever immunologically competent allogeneic lymphocytes are transfused to an immunocompromised recipient. Irradiation of blood components eliminates the risk of TA-GVHD but may damage the cellular elements in the transfused component, particularly if the cells are stored for prolonged periods in the irradiated state. To study the effect of irradiation on long-term storage of red cells, AS-1 red cells from eight normal subjects were prepared on two occasions. On one occasion, the units were stored as standard AS-1 red cells for 42 days at 4 degrees C; on the other, they were exposed to 3000 cGy radiation within 4 hours of collection and then were stored as AS-1 red cells for 42 days at 4 degrees C. The donations were at least 12 weeks apart. Irradiated units demonstrated significant elevations in poststorage plasma hemoglobin (Hb) (623 +/- 206 vs. 429 +/- 194 g/dL [6230 +/- 2060 vs. 4290 +/- 1940 g/L], p less than 0.02) and plasma potassium (78 +/- 4 vs. 43 +/- 9 mEq/L [78 +/- 4 vs. 43 +/- 9 mmol/L], p less than 0.01) and significant decreases in red cell ATP (1.9 +/- 0.2 vs. 2.1 +/- 0.3 microM/g Hb, p less than 0.04) and 24-hour posttransfusion red cell recovery (68.5 vs. 78.4%, p less than 0.02), as compared to nonirradiated units. It can be concluded that irradiation with 3000 cGy damages red cells and that long-term storage in the irradiated state may enhance this damage. Red cells should not be stored for 42 days after irradiation with 3000 cGy.  相似文献   
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Patients who have undergone allogeneic bone marrow transplantation (allo-BMT) are susceptible to a variety of opportunistic infectious complications in the months to years after engraftment. Impaired in vitro T-cell functions have been documented in these patients, and these T-cell dysfunctions contribute to the prolonged immune deficiency after allo-BMT. In the present study, we examined the expression of CD26 as well as the reconstitution of CD26-mediated T-cell costimulation via the CD3 and CD2 pathways at various times in patients aged greater than 18 years after CD6-positive, T-cell depleted allo- BMT. We found that the percentage of CD26- and CD3-positive cells, as well as the levels of expression of both antigens, was lower than in normal controls during the first 4 months after CD6-depleted allo-BMT. Subsequently, the amount of lymphocytes expressing CD3 and CD26 and the quantitative surface expression of CD3 and CD26 were not significantly different in patients and normal controls. Functional studies showed that CD26-mediated T-cell proliferation via the CD3 pathway was considerably improved and almost reached normal levels by 1 year, whereas recovery of CD26-mediated T-cell proliferation via the CD2 pathway was delayed for at least 2 years after CD6-depleted allo-BMT. As CD26 involvement in the regulation of human thymocyte activation is restricted preferentially to the CD3 pathway--unlike its involvement with both CD3 and CD2 pathways of peripheral T cells--our results suggest that the different effects of CD26-mediated costimulation via the CD3 and CD2 pathways after CD6-depleted allo-BMT may be a reflection of peripheral T-cell immaturity in those individuals, similar to that seen in mature medullary thymocytes or cord T lymphocytes.  相似文献   
10.
Antigenic modulation is one of many factors determining the effectiveness of monoclonal antibody (MoAb)-mediated therapy. To select the isotype of a CD19 MoAb most suitable for radioimmunotherapy of patients with B-cell malignancies, we studied the influence of MoAb isotype on modulation, after binding of the MoAb to different cell-line cells. The CD19-IgG1 MoAb was found to induce modulation of CD19 antigens on Daudi cell line cells more rapidly than did its IgG2a switch variant. We provide evidence that this difference in modulation rate is caused by the expression of Fc gamma receptor II (Fc gamma RII) on these cells. Experiments aimed at elucidating the mechanism of Fc gamma RII involvement in modulation induction by CD19-IgG1 showed that Fc gamma RII did not comodulate with CD19 MoAbs. However, cocrosslinking of CD19 and Fc gamma RII with CD19-IgG1 MoAb resulted in enhanced calcium mobilization in Daudi cells. This increased signal induction accompanies the enhanced capping and subsequent modulation of CD19 antigens. Because Fc gamma RII is expressed in varying densities on malignant B cells in all differentiation stages, our results have implications for the MoAb isotype most suitable for use in MoAb-based therapy of patients with B-cell malignancies.  相似文献   
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