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41.
目的研究饮食锌缺乏对神经病理性疼痛模型小鼠痛域的影响。方法制备饮食锌缺乏小鼠,采用小鼠坐骨神经分支选择损伤模型,金属自显影和原子吸收光谱检测小鼠脊髓后角锌稳态,检测小鼠痛域。结果 AMG结果证实,与假手术组相比,模型组小鼠和锌缺乏组小鼠脊髓后角游离锌离子减少,与模型组小鼠相比,锌缺乏小鼠脊髓后角游离锌离子减少。原子吸收光谱结果表明,锌缺乏组小鼠总锌含量较假手术组减少。痛域检测结果表明,锌缺乏小鼠痛域下降。结论锌离子可能参与小鼠脊髓后角痛觉专递。  相似文献   
42.
目的:探讨对巨大下颌骨囊性病变进行分期治疗的效果。方法:选择2005—2009年在本院收治的下颌骨范围大于5cm的囊性病变18例,其中伴牙列不齐者6例,一期局麻下行减压术,待范围减小至小于原来的1/2后,行二期全麻下囊性病变摘除术,即刻Bio-oss骨粉植入,术后每月定期拍摄口腔全景片观察骨密度变化,伴牙列不齐的6例患者手术后2个月开始以常规正畸加力牵引。结果:一期术后4~6个月,病变减小至原来的1/2左右,二期术后6~12个月,骨粉与周围正常骨密度基本一致,2~3a后无一例复发。6例牙列不齐的患者,经1~2a正畸治疗后,错畸形得以矫正。结论:分期治疗既彻底摘除了病变,又保存了下颌骨的连续性及自体牙,还可同时结合正畸治疗,改善错畸形,提高美学效果。  相似文献   
43.
Ambiguous phenotypes and genotypes were observed in 16 children with acute leukemia. Surface marker, cytogenetic, molecular genetic, and DNA flow cytometric analyses as well as standard morphologic and cytochemical studies were used to divide the patients into three groups. The first group comprised five children with acute leukemia whose blast cells were morphologically lymphoid, while immunophenotyping disclosed simultaneous expression of early pre-B cell and myeloid features. Molecular genetic studies showed evidence of heavy-chain immunoglobulin (Ig) gene rearrangements in all patients. Cytogenetic data, available in three of these children, revealed t(4;11). In five of the 16 patients, morphologic and surface marker analyses indicated the coexistence of two separate cell populations, one with myeloid and the other with early pre-B cell features. Further evidence of B cell commitment in these patients was provided by demonstration of Ig heavy-chain gene rearrangements in all five patients. Surprisingly, one of the five patients showed oligoclonal Ig heavy-chain as well as monoclonal gene rearrangement for the beta chain of the T cell receptor (beta-TCR). The last group consisted of four cases with otherwise typical acute lymphoblastic leukemia (ALL), early pre-B cell phenotype, and coexpression of myeloid or T cell-associated antigens, and two children with unequivocal acute myeloid leukemia (AML) and coexpression of T cell antigens. Gene rearrangement of Ig heavy-chain could be demonstrated in five of six patients, additional Ig light-chain gene rearrangement in two children with ALL, and bigenotypic features (Ig heavy-chain and beta-TCR gene rearrangement) in one patient. In none of the 16 patients did flow cytometry disclose clonal abnormalities of leukemic cell DNA content. Based on these findings, we suggest that malignant transformation in the first and second group of patients took place at a stage ontogenetically close to the pluripotent stem cell, whereas ambiguous phenotypes in the third group resulted from aberrant gene expression or insufficient reagent specificity.  相似文献   
44.
目的:探讨小鼠角膜移植排斥反应中植片浸润细胞类型及引流淋巴结细胞表型的变化。 方法:建立小鼠角膜移植模型,术后不同时间点进行临床观察及角膜免疫荧光组织化学染色。采用三色流式细胞术分析移植术后3d颌下淋巴结(SMLN)、颈浅淋巴结(SCLN)的细胞表型变化。 结果:角膜移植术后6h,中性粒细胞、树突状细胞、巨噬细胞开始聚集并逐渐浸润植片;24hCD4^+T和CD8^+T细胞出现并侵入植片,2wk时达到高峰;术后12~21d所有植片均被排斥。移植后3dSMLN内CD4^+T细胞比例较正常时明显下降(P=0.038),而SCLN各细胞比例无明显变化。 结论:角膜移植术后植片迅速出现髓系及淋巴细胞浸润,伴有引流的SM LN内早期CD4^+T细胞比例下降,二者间有一定关联。  相似文献   
45.
Bradley  WG  Jr; Kortman  KE; Crues  JV 《Radiology》1985,156(1):93-98
Resolving power is a useful measure of the magnetic resonance (MR) imager-determined ability to discriminate subtle disease. Optimizing the resolving power produces the best MR images. The resolving power improves with higher spatial resolution, signal-to-noise ratio, and object contrast. Resolving power degrades with increased patient motion, which can be associated with prolonged imaging times. High and low object contrast 0.35-T MR images of the central nervous system are compared at different levels of spatial resolution and signal-to-noise ratios. In systems that have a marginal signal-to-noise ratio, the resolving power can actually decrease when higher spatial resolution is used due to further lowering of signal-to-noise ratio and to increased motion resulting from longer imaging times. This decreases the conspicuity of small, low contrast lesions.  相似文献   
46.
Bret  PM; de Stempel  JV; Atri  M; Lough  JO; Illescas  FF 《Radiology》1988,169(2):405-407
Seventeen normal cadaver livers were studied to assess the anatomic relationship of bile ducts to portal veins. The common bile duct, main portal vein, and hepatic artery were cannulated and injected with air, dilute contrast medium, and mineral oil, respectively. The livers were placed in anatomic position and examined with computed tomography. In the lateral segment of the left hepatic lobe, the bile ducts were anterior to the portal vein in seven cases, posterior in seven, and tortuous (ie, both anterior and posterior) in three. In the medial segment of the left lobe, the bile ducts were anterior in four cases, posterior in four, tortuous in three, and not seen in six. In the right lobe, the bile ducts were anterior in nine cases, posterior in five, tortuous in one, and not seen in two. In the porta hepatis, the bile ducts were anterior in ten cases, posterior in one, tortuous in five, and not seen in one. Histologic findings confirmed the anterior and posterior location of the bile ducts relative to the portal veins. These findings contradict the commonly held view of intrahepatic bile ducts being anterior to the portal vein and are clinically significant for techniques such as bile duct drainage.  相似文献   
47.
Symptomatic superficial femoral artery (SFA) disease presenting either with severe claudication or critical limb ischaemia is treated with bypass surgery and traditionally has been the ‘goldstandard’ procedure. Surgical bypass using autogenous vein or prosthetic grafts as a conduit is well accepted and there are comparable patencies and limb salvage rates with either conduit.1There have been considerable advances in the last two decades in percutaneous endovascular technology for the treatment of SFA disease. The techniques that have been developed include percutaneous balloon angioplasty and stenting, with variable results.2,3 Despite having three different options, namely surgical bypass, balloon angioplasty and stenting, none is superior to the other.Although the five-year primary patency rate of femoropopliteal above-the-knee bypass with autogenous saphenous vein is 70%, this method of treatment is invasive with long incisions in the lower extremities and a peri-operative complication rate of 12%.4 Vascular surgeons have become more experienced with catheter-based technology and due to the minimal invasiveness of the procedure, both patients and vascular surgeons are increasingly attracted to endovascular procedures. Mwipatayi et al.5 and Nguyen et al.6 found stenting resulted in equivalent outcomes when compared to balloon angioplasty alone, but Laird et al.7 found that self-expanding nitinol stents were associated with better angiographic results and improved patency compared with balloon angioplasty alone.Randomised, controlled trials comparing bypass surgery and balloon angioplasty alone generally showed similar outcomes in terms of amputation-free survival but in the short term, surgery was more expensive than angioplasty.8 Another study comparing surgical bypass with balloon angioplasty and stenting showed better primary patency for the stent group (67%) than the bypass group (49%) and there were higher re-intervention rates in the bypass group.9Since there are conflicting data in the literature regarding the success of different methods of treatment of SFA disease and there is a lack of consensus guidelines on the optimum management of SFA disease, the aim of this study was to compare the results of stenting and surgical bypass in the local environment with regard to limb salvage rates in patients with severe leg ischaemia.  相似文献   
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目的 分析前列腺癌患者调强放疗计划设计时PBC和AAA算法计算得到的剂量学参数差异。方法 对13例术后接受调强放射治疗的前列腺癌患者进行调强放疗计划设计时,分别用Eclipse Version 8.10治疗计划系统提供的PBC和AAA算法进行剂量计算并用二维电离室矩阵进行验证测量,比较两种算法获得的HI、CI、PTVDP、PTVmean、直肠和膀胱V50等参数差异,并将二维电离室矩阵测量的剂量分布与两种算法的计算结果分别进行比较获得γ通过率、单次照射时的及DDmean等参数差异。结果 两种算法得到的靶区HI、CI、PTVDP、PTVmean平均相差分别为0.003、0.004、2.2%、10 cGy,直肠和膀胱V50值平均差异分别为0.3%和1.3%。γ通过率、DDmax及DDmean平均差异分别为0.9%、1.2%(2.4 cGy)和0.85%(1.7 cGy)。两种算法所获得的剂量学参数差异不大。结论 对前列腺癌患者进行调强放疗计划设计时,PBC和AAA两种算法均可使用。  相似文献   
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