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891.
目的:探讨牙槽突裂植骨区牙移入的可行性及牙移入的方式,评价移入牙的牙槽骨支持率和移植骨高度变化。方法:选取唇腭裂伴牙槽突裂患者10例,行牙槽突裂自体髂骨植骨术后,分别拍摄植骨后3个月(T1)及牙移入植骨区后(T2)的根尖片,观察牙移入植骨区的情况,测量T1和T2阶段移入牙的牙槽骨支持率,采用SPSS17.0软件包对测量数据进行配对t检验,并参照Bergland四分法评价移植骨的高度变化。结果:①牙整体移入植骨区,牙槽骨支持率为(89.85±2.51)%(T1)和(90.22±2.44)%(T2),牙移入植骨区后的牙槽骨支持率与植骨后3个月的牙槽骨支持率无显著差异(P>0.05)。②移植牙槽骨的高度在牙移入前后无显著变化。结论:唇腭裂患者植骨后,可将裂隙邻近的牙移入植骨区,获得良好的牙槽骨支持。牙的移入有助于维持移植骨高度,提高植骨的成功率。  相似文献   
892.
目的:评价牙移动产生的功能性刺激对SD大鼠牙槽突裂植骨区骨改建的影响,探讨植骨后牙移动的合适时机。方法:选择16只56天的雄性SD大鼠,随机分为4组,按照已建立的外科诱导SD大鼠双侧牙槽突裂模型要求造裂,填塞骨蜡8周后,在双侧裂隙区同时植入大鼠自体髂骨松质骨,左侧为牙移动侧,分别在植骨后即刻、2周、4周、8周近中移动左侧第二磨牙进入植骨区,右侧为对照侧,第二磨牙不进行任何处理。加力牙移动4周后处死动物。通过Micro-CT扫描标本,运用Mimics 10.01软件计算双侧植骨区骨量,采用SAS 9.0软件包对双侧植骨区骨量进行配对t检验,对双侧植骨区骨量的差值进行组间方差分析。结果:各组的牙移动侧植骨区骨量均多于对照侧。0周组牙移动侧与对照侧植骨区骨量差值为0.87mm3,无显著差异(P>0.05);2周组和4周组牙移动侧与对照侧植骨区骨量的差值分别为1.7mm3和1.77mm3,有显著差异(P<0.05);8周组牙移动侧与对照侧植骨区骨量的差值为3.47mm3,有显著差异(P<0.01),8周组两侧植骨区骨量差值的均数与0周组、2周组和4周组均有显著差异(P<0.05)。结论:牙移动对植骨区的功能性刺激能抑制植骨区的骨吸收。植骨8周后的牙移动抑制植骨区移植骨吸收的作用最为明显。  相似文献   
893.
The transfusion of blood products can result in a variety of consequences, including transfer of pathogens and the induction of immune responses, such as the almost invariably fatal transfusion-associated graft-versus-host disease (TA-GVHD). Exposure of blood products to γ-irradiation is currently the standard of care for the prevention of TA-GVHD. Regulatory, technical and clinical challenges associated with the use of γ-irradiators are driving efforts to develop alternatives. Initially, pathogen reduction methods were developed to reduce the risk of microbial transmission by blood components. Through modifications of nucleic acids, these technologies interfere with the replication of both pathogens and leucocytes. These methods have been found to be as effective as γ-irradiation in preventing T lymphocyte proliferation and TA-GVHD responses. Additional benefits of pathogen reduction protocols potentially include inhibition of antigen presentation, cytokine production and activation of lymphocytes.  相似文献   
894.
In a study conducted on 114 patients undergoing unrelated donor haematopoietic stem cell transplantation (HSCT) for thalassaemia, we observed that the lack of activating killer immunoglobulin-like receptors (KIRs) on donor natural killer (NK) cells significantly increased the risk of graft-versus-host disease (GvHD) [hazard risk (HR) 4.2, 95% confidence interval (CI) 1.7-10.1, P = 0.002] and transplantation-related mortality (HR 4.7, 95% CI 1.6-14.2, P = 0.01). The risk of GvHD furthermore increased when recipients heterozygous for HLA-C KIR ligand groups (C1/C2) were transplanted from donors completely lacking activating KIRs (HR 6.1, 95% CI 1.9-19.2, P = 0.002). We also found that the risk of rejection was highest when the recipient was homozygous for the C2 HLA-KIR ligand group and the donor carried two or more activating KIRs (HR 6.8, 95% CI 1.9-24.4, P = 0.005). By interpolating the number of donor activating KIRs with recipient HLA-C KIR ligands, we created an algorithm capable of stratifying patients according to the immunogenetic risk of complications following unrelated HSCT. In clinical practice, this predictive tool could serve as an important supplement to clinical judgement and decision-making.  相似文献   
895.
A joint working group established by the Haemato-oncology subgroup of the British Committee for Standards in Haematology (BCSH) and the British Society for Bone Marrow Transplantation (BSBMT) has reviewed the available literature and made recommendations for the diagnosis and management of chronic graft-versus-host disease (GvHD). This guideline includes recommendations for the diagnosis and staging of chronic GvHD as well as primary treatment and options for patients with steroid-refractory disease. The goal of treatment should be the effective control of GvHD while minimizing the risk of toxicity and relapse.  相似文献   
896.
Diagnosis and management of acute graft-versus-host disease   总被引:1,自引:0,他引:1  
A joint working group established by the Haemato-oncology subgroup of the British Committee for Standards in Haematology (BCSH) and the British Society for Bone Marrow Transplantation (BSBMT) has reviewed the available literature and made recommendations for the diagnosis and management of acute graft-versus-host disease. This guideline includes recommendations for the diagnosis and grading of acute graft-versus-host disease as well as primary treatment and options for patients with steroid-refractory disease. The goal of treatment should be effective control of graft-versus-host disease while minimizing risk of toxicity and relapse.  相似文献   
897.
The clinical significance of mixed chimerism following allogeneic haematopoietic stem cell transplantation (HSCT) remains controversial. Its relevance and incidence are probably influenced by the conditioning regimen and incorporation of T‐cell depletion. The presence of recipient chimerism levels >40–50% following T‐cell replete reduced intensity transplantation correlates with a high risk of graft rejection, regardless of donor‐lymphocyte infusions, but it is unclear whether this finding translates to T‐cell depleted transplants. We conducted a retrospective single‐institution analysis of patients receiving alemtuzumab‐based HSCT. 27/152 (18%) evaluable cases had predominantly recipient T‐cell chimerism at 3 months or beyond. By contrast, coincident chimerism in the granulocyte lineage was predominantly of donor origin (median 100%) in all but one patient. Donor lymphocyte infusion effectively converted predominantly recipient T‐cell chimerism to ful donor chimerism in all evaluable cases including three cases with no detectable donor T cells. The only graft failure occurred in the patient with predominantly recipient myeloid chimerism in whom rejection occurred rapidly before donor lymphocytes could be administered. We conclude that predominant or complete recipient T‐cell chimerism following alemtuzumab‐based regimens does not have the same clinical implications as that following T‐cell replete transplants and can be effectively converted with donor lymphocytes without the need for lympho‐depleting agents or re‐conditioning.  相似文献   
898.
We describe a comprehensive surveillance system involving infection control practitioners, surgeons, administrative staff, and patients aimed at improving the postdischarge surveillance of surgical site infections. The system was able to detect 22 infections out of 538 procedures, 95% of which were detected during the postdischarge period.  相似文献   
899.
900.
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