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Lymphoid neogenesis is the process by which ectopic lymphoid accumulations that resemble lymph nodes arise in nonlymphoid tissues. Such lymphoid accumulations, known as tertiary lymphoid organs (TLO), are observed in chronic autoimmunity and they propagate immune pathology by setting up local antigen presenting sites. Whether lymphoid neogenesis occurs in transplanted organs and contributes to rejection is not well understood. To begin to address this question, we retrospectively analyzed 319 murine cardiac allografts for microscopic evidence of lymph-node-like structures. We found 78 allografts that had either classical TLO, characterized by discrete T- and B-cell zones and high endothelial venules (HEV) expressing peripheral node addressin (PNAd) (n = 34), or PNAd(+) HEV without organized lymphoid accumulations (n = 44). These changes were present in both short- and long-lived allografts and were invariably associated with rejection. Importantly, they occurred in 78% of allografts undergoing chronic rejection (n = 85) but in only 7% of allografts undergoing primarily acute rejection (n = 184). These findings indicate that, like autoimmunity, alloimmunity is associated with lymphoid neogenesis in the target organ and suggest a role for local T-cell activation in chronic allograft rejection.  相似文献   
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A new technique for earlobe reconstruction is described, illustrated by a case report. This technique uses double-crossed skin flaps from the pre-auricular and retromandibular areas. No skin grafts and no cartilage framework are needed. This technique is particularly indicated for immediate earlobe reconstruction.  相似文献   
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Nebulization of aqueous solutions is a convenient delivery system to deliver drugs to the lungs because it can produce droplets small enough to reach the alveolar region. However, the droplet size might be affected by the changes in the temperature and the concentration of the nebulizing solution in the reservoir during nebulization. In this study, the changes in the droplet size over the nebulization time using a PariBoy air-jet and a Multisonic ultrasonic nebulizer have been studied. The findings were related to changes in the temperature, concentration, surface tension, viscosity and saturated vapour pressure of the nebulizing solution. By using the jet nebulizer, an increase in the droplet size followed by a decrease has been observed. This observation could be attributed to the approx. 7 degrees C reduction of the temperature during the first 2 min in the jet nebulizer reservoir which increased the viscosity of the nebulizing solution. After this initial period of time, the increasing drug concentration induced a reduction of the surface tension and, consequently, a decrease in the droplet size. However, with the ultrasonic nebulizer a temperature increase of approx. 20 degrees C during the first 6 min in the nebulizing solution was observed leading to a decrease in droplet size, viscosity and surface tension and an increasing saturated vapour pressure. This again led to smaller average droplet sizes.  相似文献   
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A patient with malignant struma ovarii who had elevated thyroglobulin levels at the time of her original surgery was diagnosed with recurrence on the basis of progressive thyroglobulin level elevation while on thyroid suppressive therapy. Subsequent treatment with therapeutic doses of iodine-137 resulted in normalization of the elevated thyroglobulin level. The patient remains disease free on thyroid replacement.  相似文献   
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Retinoblastoma is an ocular tumor that occurs in young children, in either heritable or sporadic manner. The relative rarity of retinoblastoma, and the need for expensive equipment, anesthesia, and pediatric ophthalmologic expertise, are barriers for effective treatment in developing countries. Also, with an average age‐adjusted incidence of two to five cases per million children, patient number limits development of local expertise in countries with small populations. Lebanon is a small country with a population of approximately 4.5 million. In 2012, a comprehensive retinoblastoma program was formalized at the Children's Cancer Institute (CCI) at the American University of Beirut Medical Center, and resources were allocated for efficient interdisciplinary coordination to attract patients from neighboring countries such as Syria and Iraq, where such specialized therapy is also lacking. Through this program, care was coordinated across hospitals and borders such that patients would receive scheduled chemotherapy at their institution, and monthly retinal examinations and focal laser therapy at the CCI in Lebanon. Our results show the feasibility of successful collaboration across borders, with excellent patient and physician adherence to treatment plans. This was accompanied by an increase in patient referrals, which enables continued expertise development. However, the majority of patients presented with advanced intraocular disease, necessitating enucleation in 90% of eyes in unilateral cases, and more than 50% of eyes in bilateral cases. Future efforts need to focus on expanding the program that reaches to additional hospitals in both countries, and promoting early diagnosis, for further improvement of globe salvage rates.  相似文献   
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In pediatric RT, donor allograft size often exceeds the expected recipient norms, especially in younger recipients. An “oversize” graft might not only present a technical‐ and space‐related challenge, but may possibly lead to increased demands in perioperative volume requirements due to the disparity between donor and recipient in renal blood flow. We evaluated transfusion practices at a single tertiary institution with special consideration of kidney graft size, hypothesizing that oversize graft kidneys might lead to a quantifiable increased need of blood transfusion in smaller recipients. Retrospective analysis of all patients who underwent pediatric RT from January 2004 to June 2014 at a tertiary pediatric centre was performed. Variables analyzed included patient age, weight, pre‐ and postoperative Hb concentration, graft size, EBL, amount of intraoperative blood transfusion, and preoperative use of erythropoietin. Based on graft size in relation to patient's age, a SMR and an OvR were identified. A subcohort of age‐matched pairs was used to allow for comparison between groups. We calculated the expected procedure‐ and transfusion‐induced changes in Hb and compared these changes to the observed difference in pre‐ vs postoperative Hb to assess the influence of graft size on transfusion requirements. RT was performed in 188 pediatric recipients during the study period. In the matched cohort, percentage of transfused patients during transplantation in the OvR group was more than double compared with SMR (89% vs 39%, P < .001); similarly, the median number of transfused PRBC units in OvR was 1, while the median of SMR did not receive transfusion (P < .001). The difference between expected (calculated) and observed change in Hb was significantly higher in OvR with a median of 1.9 g/dL compared with SMR with a median of 1.0 g/dL (P = .026). Correspondingly, the calculated median volume taken up by a regular size kidney was significantly higher with 213 mL compared with 313 mL (P = .031) taken up by an oversize graft kidney. Median estimated intraoperative blood loss was significantly higher in OvR than in SMR (6.9 mL/kg, vs 5.3 mL/kg, respectively; P = .04). Median postoperative Hb was similar among groups (10.4 g/dL vs 10.6 g/dL for SMR vs OvR, respectively). Transplantation of an oversized kidney in pediatric RT recipients is associated with a quantifiable higher need for blood transfusion. This may be caused by a higher intraoperative EBL and/or greater blood volume sequestered by the larger renal allograft and requires further evaluation.  相似文献   
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艾叶油的呼吸系统药理研究-Ⅱ,抗过敏作用   总被引:9,自引:1,他引:9  
目的:本文研究艾叶油的抗过敏作用。方法:采用致敏豚鼠气管SchultzDale 反应,组胺或氨甲酰胆碱引起的豚鼠气管收缩,大鼠被动皮肤过敏,5羟色胺引起的大鼠皮肤毛细血管通透性增强,豚鼠肺组织释放过敏性慢反应物质(SRSA) ,SRSA 收缩豚鼠回肠等试验。结果:艾叶油抑制致敏豚鼠气管SchultzDale 反应(IC50 :98 .6mg/L) ;100mg/L 明显降低组胺或氨甲酰胆碱引起的豚鼠气管收缩pD2 值;明显抑制大鼠被动皮肤过敏(ID50 :0 .22g/kg) 和5羟色胺引起的大鼠皮肤毛细血管通透性增强反应(ID50 :0 .52g/kg) ;抑制豚鼠肺组织释放SRSA(IC50 :49 .7mg/L) ;拮抗SRSA 对豚鼠回肠的收缩(IC50 :34 .9mg/L) 。结论:艾叶油具有抗过敏作用,对呼吸道过敏反应有保护作用,是其治疗支气管哮喘和慢性气管炎作用机制之一  相似文献   
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