21例心内直视术后急性心包填塞的临床分析

目的:分析21例心内直视术后急性心包填塞的临床特点,探讨其发生原因、预防、救治及其二次开胸的早期指征。方法:对1991年1月-2005年12月心内直视术(共1096例)后21例急性心包填塞二次开胸(发生率1．92％)病例进行总结分析。结果:急性心包填塞患者经二次剖胸解除心包填塞后17例痊愈出院,4例死亡,二次剖胸手术死亡率为19．05％。二次剖胸手术者所患疾病包括先天性心脏病6例,瓣膜病13例,大血管手术1例,心脏移植1例。结论:减少心内直视术后出血、渗血是避免术后发生急性心包填塞的关键,早期诊断并尽早行二次剖胸手术可明显降低围手术期死亡率。     

A Bayesian approach to subvoxel tissue classification in NMR microscopic images of trabecular bone

NMR microscopy is currently being used as an investigational tool for the evaluation of micromorphometric parameters of trabecular bone as a possible means to assess its strength. Since, typically, the image voxel size is not significantly smaller than individual trabecular elements, partial volume blurring can be a major complication for accurate tissue classification. In this paper, a Bayesian segmentation technique is reported that achieves improved subvoxel tissue classification. Each voxel is subdivided either into eight subvoxels twice the original resolution, or up to four subvoxels along the transaxial direction and the subvoxels optimally classified as either bone or marrow. Based on a statistical model for partial volume blurring, the likelihood for the number of marrow subvoxels in each voxel can be computed on the basis of its measured signal. To resolve the ambiguity of the location of the marrow subvoxels, a Gibbs distribution is introduced to model the interaction between the subvoxels. Neighboring subvoxel pairs with the same tissue label are encouraged, and pairs with distinct labels are penalized. The segmentation is achieved by maximizing the a posteriori probability of the label image using the block ICM (iterative conditional mode) algorithm. The potential of the proposed technique is demonstrated in real and synthetic NMR microscopic images.     

颅咽管瘤切除术后水钠代谢紊乱机制研究

目的探讨颅咽管瘤术后水钠代谢紊乱的原因和最佳处理方式。方法对102例经胼胝体切开穹窿间入路切除巨大颅咽管瘤的病人，记录术后尿量、血电解质、抗利尿激素（ADH）、醛固酮（ALD）、皮质醇水平，比较术后激素水平变化与水、钠代谢紊乱的关系。结果本组均出现水、钠代谢紊乱，术后2周完全恢复52例，4周基本恢复33例，6周恢复12例，需长时间人工调整电解质水平5例。术后ADH、ALD和皮质醇的不足是导致术后水钠代谢紊乱的主要原因。结论颅咽管瘤切除术后水、钠代谢紊乱与手术损伤下丘脑有关，紊乱类型与ADH、ALD和醛固酮的缺乏情况有关；及时给予相应激素及对症治疗，可获满意疗效。     

显微镜下直切口锁孔微创治疗高血压性脑出血

目的探讨显微镜下直切口锁孔微创治疗高血压性脑出血的价值。方法根据CT提示血肿在头皮的投影设计手术切口部位，通过4～5cm皮肤直切口，直径2cm的骨窗，切开皮层到达血肿腔清除血肿。结果血肿完全清除17例，18例清除率达到90％，4例清除率达到80％。术后再出血2例。4例术后3周内死亡：2例死于循环呼吸功能衰竭，1例死于脑干功能衰竭，1例死于消化道出血，手术死亡率10．2％（4／39）。35例随访0．5—3年，平均2．1年，术后6个月ADL分级：1级9例，2级12例，3级9例，4级4例，5级1例，死亡4例。结论显微镜下直切口锁孔微创技术是一种快速、有效和安全的治疗高血压性脑出血的手术方法，可以解除血肿的占位压迫效应，有效止血，防止再出血，效果满意。     

颈椎病手术的麻醉管理

本文报道２３例颈椎病手术患者采用１％普鲁卡因与２％利多卡因混合液局麻加静脉哌替啶强化取得满意的效果。文中围绕呼吸管理问题对前、后手术入路的麻醉用药、输血、补液及头部固定等注意事项均作了具体介绍。     

Effect of biomaterial properties on bone healing in a rabbit tooth extraction socket model

In this work we sought to understand the effect of biomaterial properties upon healing bone tissue. We hypothesized that a hydrophilic polymer gel implanted into a bone tissue defect would impede the healing process owing to the biomaterial's prevention of protein adsorption and thus cell adhesion. To test this hypothesis, healing bone was investigated within a rabbit incisor extraction socket, a subcritical size bone defect that resists significant soft tissue invasion by virtue of its conformity. After removal of the incisor teeth, one tooth socket was left as an empty control, one was filled with crosslinked polymer networks formed from the hydrophobic polymer poly(propylene fumarate) (PPF), and one was filled with a hydrogel formed from the hydrophilic oligomer oligo(poly(ethylene glycol) fumarate) (OPF). At five different times (4 days as well as 1, 2, 4, and 8 weeks), jaw bone specimens containing the tooth sockets were removed. We analyzed bone healing by histomorphometrical analysis of hematoxylin and eosin stained sections as well as immunohistochemically stained sections. The proposed hypothesis, that a hydrophilic material would hinder bone healing, was supported by the histomorphometrical results. In addition, the immunohistochemical results reflect molecular signaling indicative of the early invasion of platelets, the vascularization of wound-healing tissue, the differentiation of migrating progenitor cells, and the formation and remodeling of bone tissue. Finally, the results emphasize the need to consider biomaterial properties and their differing effects upon endogenous growth factors, and thus bone healing, during the development of tissue engineering devices.     

In vitro degradation of polymeric networks of poly(propylene fumarate) and the crosslinking macromer poly(propylene fumarate)-diacrylate

Polymeric networks of poly(propylene fumarate) (PPF) crosslinked with poly(propylene fumarate)-diacrylate (PPF-DA) are currently being investigated as an injectable, biodegradable bone cement. This study examined the effect of crosslinking density, medium pH, and the incorporation of a beta-tricalcium phosphate (beta-TCP) filler on the in vitro degradation of PPF/PPF-DA. Cylindrical specimens were submerged in buffered saline at 37 degrees C and the change in weight, geometry, and compressive mechanical properties were monitored over a 52-week period. All formulations showed an initial increase in modulus and yield strength over the first 12 weeks, achieving maxima of 1307+/-101 and 51+/-3MPa, respectively, for the beta-TCP composite. PPF/PPF-DA networks with the lower crosslinking density demonstrated the greatest degradation with a 17% mass loss. Samples in the lower buffer pH 5.0 compared to physiological pH 7.4 did not show any differences in mass loss, but exhibited a faster decrease in the compressive strength over time. The beta-TCP composites maintained their mechanical properties at the level following their initial increase. These results show that the degradation of PPF/PPF-DA networks can be controlled by the crosslinking density, accelerated at a lower pH, and prolonged with the incorporation of the beta-TCP filler.     

Increased frequency of the rare PstI allele (P2) in a population of CAD patients in Northern Greece

Restriction fragment length polymorphisms (RFLPs) at the apolipoprotein AI-CIII-AIV gene cluster and their association with coronary artery disease (CAD) and lipid levels were studied in a Northern Greek population. Ninety-five patients with CAD and fifty-four normal controls, angio-graphically proven, were included in this study. Using genomic hybridization techniques, three polymorphic restriction sites were identified at this locus: the PstI at the 3' end of the apoAI gene, the SacI at the 3' non-coding region of the apoCIII gene and the PvuII at the intergenic region between the apoCIII-AIV genes. The rare allele (P2) arising from the absence of the PstI restriction site was observed with a significantly higher frequency (p<0.01) in patients compared to normals (0.11 vs 0.02). In contrast, the rare allele for the SacI polymorphic site had a similar distribution among patients and controls (0.12 vs 0.16). The same was observed for the PvuII RFLP (0.04 vs 0.05). Correlation of lipid and apolipoprotein AI levels with the three RFLPs revealed no significant association, although apo AI and HDL were lower in patients with the P2 allele. Thus, in this Greek population, only the PstI polymorphism, among the polymorphic restriction sites examined, appears to be associated with CAD.     

实验性哮喘豚鼠初级传入系统和中枢内NKB的变化(英文)

本文应用放射免疫分析方法，测定了16只哮喘豚鼠初级传入系统和中枢内神经激肽β（NKB）的水平。结果表明，与正常对照组（结状神经书3228±11．89，C7～C8段脊神经节23．63±13．26，T1～T2段脊神经节24．25±1819，T3～T5段脊神经节25．53±12．34，C7～T5段脊髓后角28．65±16．59，孤束核26．34±18．36Pg／gwettissue）相比较，哮喘豚鼠初级传入系统和中枢内（结状神经节43．26±12．35，C7～C段脊神经节32．53±17．63，T1～T2段神经书32.25±20．65，T3～T5段脊神经节34．36±15．33，C7～T5段脊髓后角39．53±2028，孤束核3662±17．85Pg／gwettissue）NKB的含量明显高于对照组（P＜0．05）。结合NKB在呼吸道的作用，这些结果提示，初级传入系统和中枢内的NKB可能参与哮喘发病的病理生理机制。