兔坐骨神经挤压伤的MRI与SEP对比研究

目的:探讨磁共振成像和体感诱发电位以及两者结合在坐骨神经急性挤压伤中的诊断价值。方法:24只兔按钳夹力的不同随机分为A、B两组,左后肢为损伤侧,右后肢为对照侧,建立坐骨神经急性挤压伤模型,于伤后1、2、4、8周行MR扫描,同时行双侧体感诱发电位检查。结果:损伤侧24条神经,有23条MR显示异常,诊断正确率95.8%,假阴性率4.17%(1/24);24条损伤侧坐骨神经,有22条SEP显示异常,诊断正确率91.6%,假阴性率8.3%(2/24)。MRI与SEP对神经损伤的正确诊断率无统计学差异(P>0.05)。MRI与SEP结合起来,24条损伤神经均显示异常,诊断正确率100%。结论:MR与SEP检查可无创、准确地判断神经损伤,两者结合可明显提高神经损伤的正确诊断率,重复性好,可作为神经损伤的较好诊断手段。     

骨巨细胞瘤的MRI诊断价值

目的探讨骨巨细胞瘤的MRI表现特点及其病理基础。资料与方法搜集经手术病理证实的12例骨巨细胞瘤患者资料，分析其MRI征象并与病理结果对照。结果T1WI上肿瘤实体表现为低、等信号，T2WI上为不均匀高信号，Gd-DTPA增强扫描呈中度到明显强化。此外，MRI还可显示肿瘤内坏死、出血、含铁血黄素沉着等。结论MRI能够提供比较全面的影像学信息，可提高对骨巨细胞瘤诊断的准确性。     

嗜铬细胞瘤患者围手术期处理的改进

目的：探讨提高嗜铬细胞瘤患者围手术期安全性的措施。方法：对15例嗜铬细胞瘤患者、术前采用选择性α1受体阻滞剂多沙唑嗪控释片(可多华)控制高血压；11例患者采用3D DCEMRA进行肿瘤定位；术中均采用联合高容量血液稀释(AHH)和术中患者自体血回输纠正血容量。结果：除1例持续性高血压患者需联合钙离子拮抗剂和ACEI药物降压外．其余患者血压控制均为满意；根据3D DCEMRA定位选择手术径路者均顺利完成手术；AHH联合术中自体血回输使14例患者避免了异体输血。结论：本文围手术期处理改进．可多华可明显减少药物的不良反应；采用3D DCEMRA进行肿瘤定位，可增加手术安全性；AHH联合术中自体血回输可减少医疗成本和异体输血，以及由此而引起的并发症。     

应用吻合器行中、下段直肠癌切除术后吻合口漏──附10例报告

我科自１９８１年３月至１９９１年１２月应用吻合器行中、下段直肠癌切除术６７例，同期发生吻合口漏１０例（１４９％）。本文分析了吻合口漏发生的因素。病变部位、病灶范围、术中操作技术、术前肠道灌洗以及术后骶前引流是影响吻合口漏的重要因素。本文总结了吻合口漏的治疗方法，提倡保守治疗，或加作暂时性横结肠造口术。     

用Fura-2测定周围血单个核细胞内游离钙浓度

本文用Fura-2测定了周围血单个核细胞内游离钙浓度，并对有关实验条件进行了探讨。对比研究表明，血标本在4℃保存4小时对测定结果无显著影响，测定标本中单个核细胞数以10~5～10~6/ml为宜。认为测定单个核细胞内游离钙浓度对判断单个核细胞的功能状况有一定帮助。     

前臂逆行骨间背侧皮瓣的临床应用

目的总结前臂逆行骨间背侧皮瓣的临床疗效。方法回顾性分析42例前臂逆行骨间背侧皮瓣，并结合文献阐明其变异程度及变异的处理。结果骨间背侧血管在前臂中1／3缺如1例．皮瓣边缘坏死；皮瓣向近端延伸超过4cm者4例，远端坏死，延迟愈合；其余均一期愈合：结论虽然前臂骨间背侧血管有变异，但前臂逆行骨间背侧皮瓣仍是修复手背中等大小创面较为理想的方法，以近点皮肤穿支向近端延伸皮瓣不要超过4cm。     

腮腺外面神经颊支的应用解剖研究

目的:观测面神经颊支出腮腺后的各级分支,为相关外科手术提供解剖学依据。方法:10例(20侧)防腐人头标本,描述面神经颊支出腮腺后的走行、定位及层次。结果:面神经颊支出腮腺后分为2～4支,均走行在SMAS筋膜下;颊Ⅰ、颊Ⅱ恒定出现,其一级分支距腮腺导管分别为(1.1±0.5)cm及(0.5±0.3)cm,且分别向前走行(1.3±0.9)cm及(1.8±0.5)cm后发出二级分支。结论:面神经颊支较为恒定,在面瘫治疗中健侧面神经颊支的二级分支可以作为受体神经,可不损伤面神经颊支主干。面神经颊支的分布及走行也可指导除皱术、扩张器植入、瘢痕切除等手术的剥离范围,不致产生并发症。     

Sympathoadrenal excitation and inhibition by lower brainstem stimulation in cats

Effects of stimulation of brainstem sites on hemodynamics and plasma catecholamine levels were assessed in cats under chloralose-urethane anesthesia. Pressor areas of the dorsal medulla (DM) and ventrolateral medulla (VLM) and the depressor area of the paramedian reticular nucleus (PRN) were stimulated electrically using a monopolar electrode, or chemically using sodium glutamate microinjection. Plasma levels of norepinephrine (NE) and epinephrine (EPI) were measured in caval blood above the adrenal veins. Electrical stimulation of the DM and VLM produced increases in blood pressure and in plasma NE and EPI levels that were enhanced after acute vagotomies. The NE and EPI responses were attenuated after acute, bilateral adrenalectomies, confirming augmented adrenomedullary secretion, whereas the pressor responses were intact. Injection of sodium glutamate into the same pressor regions of the DM or VLM also produced pressor responses and elevated plasma catecholamine levels, indicating that the responses resulted from activation of neuronal perikarya. Stimulation of the PRN attenuated pressor and catecholamine responses during stimulation of the DM and VLM. The results indicate that pressor responses during stimulation of the DM and VLM are due at least partly to activation of perikarya in these regions, are associated with but not dependent on adrenomedullary activation, and are enhanced after vagotomy; and that neurons of the PRN exert inhibitory modulation of the pressor and adrenomedullary responses during stimulation of VLM and DM.     

Post-stimulus depression of reflex changes in circular muscle activity in the guinea pig small intestine.

The extent and time course of depression of successive reflex responses recorded with intracellular microelectrodes from the circular smooth muscle of the guinea pig small intestine were determined. Two stimuli were used, distension and distortion of the mucosa by compression; these were applied either at the same or at different sites. Excitatory responses oral and inhibitory responses anal to the stimuli were recorded. Post-stimulus depression of both ascending excitatory and descending inhibitory reflexes occurred, but the extent of depression was slightly less for the descending inhibition. A conditioning distension lasting 9 s depressed the excitatory response to a test distension applied 2 s later at the same site by 90%. After 30 s the depression was 50% and test responses were normal if inter-stimulus intervals were increased to 2 min. Increasing the duration of the conditioning stimulus increased the depression. Post-stimulus depression was less for compression stimuli than for distension stimuli and prior mucosal compression had almost no effect on responses to subsequent distension. The post-stimulus depression was greater if conditioning and test stimuli were at the same rather than different sites. For different sites, conditioning stimuli at 15 mm from the recording site (near) depressed responses to stimuli at 30 mm (far) to a greater extent than far stimuli depressed responses to near stimuli. If the conditioning stimulus at 15 mm was maintained until after the far test stimulus was applied, depression of the test response did not occur. It is concluded that the major sites of post-stimulus depression are at the synapses between primary sensory neurons and the first interneurons of reflex pathways, and that post-stimulus depression also occurs at other places in the pathway, presumably at synapses between interneurons or between interneurons and motor neurons.     

Soluble Fcγ receptors in periodontal lesions

Soluble Fcγ-binding components were detected in gingival fluid from periodontal lesions by incubation with biotinylated human Fcγ fragments. FcγIII receptor was identified by incubation of gingival fluid with monoclonal antibody. Sodium dodecyl sulfate-polyacrylamide gel electophoresis and Western transfer showed that most of the Fcγ-binding components had minimal mobility in a 4–15% gradient gel under nonreducing conditions. Under reducing conditions, the main band of Fcγ-binding components in gingival fluid migrated corresponding to protein A of 49 kDa. The pattern of Fcγ-binding components was similar in serum and gingival fluid except for the observation in gingival fluid of Fcγ-binding components migrating like standard proteins of 19 to 20 kDa, a size that corresponds to the polypeptide part of FcγII receptor and FcγIII receptor.