Ultrasound Examination and Localization of the Sciatic Nerve: A Volunteer Study

Background: Few studies have examined the use of ultrasound for sciatic nerve localization. The authors evaluated the usefulness of low-frequency ultrasound in identifying the sciatic nerve at three locations in the lower extremity and in guiding needle advancement to target before nerve stimulation.

Methods: In this prospective observational study, 15 volunteers underwent sciatic nerve examination using a curved ultrasound probe in the range of 2-5 MHz and a Philips-ATL 5000 unit (ATL Ultrasound, Bothell, WA) in the gluteal, infragluteal, and proximal thigh regions. Thereafter, an insulated block needle was advanced inline with the ultrasound beam to reach the nerve target, which was further confirmed by electrical stimulation. The quality of sciatic nerve images, ease of needle to nerve contact, threshold stimulating current, and resultant motor response were recorded.

Results: The sciatic nerve was successfully identified in the transverse view as a solitary predominantly hyperechoic structure on ultrasound in all of the three regions examined. The target nerve was visualized easily in 87% and localized within two needle attempts in all patients. Nerve stimulation was successful in 100% after two attempts with a threshold current of 0.42 +/- 0.12 (mean +/- SD) eliciting foot plantarflexion or dorsiflexion.     

nm23-H1基因转染对人胆管癌细胞系QBC939体外浸润能力的影响

目的：探讨nm23-H1基因转染对人胆管癌细胞系QBC939体外浸润能力的影响。方法：将含有全长nm23-H1 cDNA的真核表达载体通过脂腩体法转染人胆管癌细胞系。结果：转染成功的QBC939细胞，其nm23-Hl基因的mRNA、蛋白表达明显增加，转染nm23-H1基因的胆管癌细胞体外浸润能力下降，穿越matrigel的细胞数明显低于亲本QBC939细胞，代表浸润能力的IV型胶原酶（MMP-9）分泌量下降。结论：nm23-Hl基因可以抑制胆管癌细胞的体外浸润能力。     

3H]Ro 19-6327: a reversible ligand and affinity labelling probe for monoamine oxidase-B

This study demonstrated the existence of specific binding sites for [3H]Ro 19-6327 in human platelet membranes. This compound is a novel, time-dependent inhibitor of monoamine oxidase type B (MAO-B) and is structurally closely related to [3H]Ro 16-6491. The density of the sites labelled with high affinity by [3H]Ro 19-6327 was similar to that observed in previous studies with [3H]Ro 16-6491 as ligand. Binding was reversible at 20 degrees C and showed a relatively slow dissociation (t1/2 = 220 min). The dissociation rate was markedly decreased (t1/2 = greater than 24h) at 0 degrees C. MAO-B, but not MAO-A inhibitors, effectively prevented the binding of [3H]Ro 19-6327. Like [3H]Ro 16-6491, [3H]Ro 19-6327 is recognized as a substrate by MAO-B, being eventually deaminated by the enzyme. Since the deaminated aldehyde derivative of Ro 19-6327 did not inhibit MAO-B, a still unidentified reversible adduct, formed at the MAO-B active site, might explain the high potency and selectivity of [3H]Ro 19-6327. Incubation of the radioligand-enzyme complex from platelet and brain membranes with NaBH3CN and acetic acid (to pH 4.5) caused the irreversible incorporation of the radioactivity into a single polypeptide as shown by SDS-PAGE analysis. This polypeptide had a molecular weight identical to that of the MAO-B subunit, i.e. 58,000. The presence of unlabelled MAO-B inhibitors in the incubation mixture prevented the covalent incorporation of [3H]Ro 19-6327. The irreversible MAO-B inhibitor, [3H] pargyline, labelled a protein with a molecular weight identical to the protein labelled by [3H]Ro 19-6327.(ABSTRACT TRUNCATED AT 250 WORDS)     

A model-based detector of vertex waves and K complexes in sleep electroencephalogram.

A model of sleep phasic events such as vertex waves, K complexes, delta waves and sleep spindles is proposed. It consists of feedback loops that are driven by white noise (simulating tonic delta and sigma activity) and by isolated random impulses, simulating vertex waves or K complexes, depending on the background tonic activity. A model-based method for the detection of sleep phasic events was implemented in a personal computer. Its performance was investigated using simulated and real whole-night EEG signals. The method was able to detect K complexes and vertex waves in a reliable way in spite of their variable shapes and in the presence of a variety of background activities. The detector appears to have superior performance to those so far reported in the literature. The performance of the detector was also compared to that of an electroencephalographer using normal sleep EEG records of 8 h duration from 6 subjects. The performance was satisfactory both in terms of accuracy and reliability. The problem of detecting K complexes in stages 3 and 4 of sleep is discussed.     

以院务公开为根本 积极探索治理医药购销领域商业贿赂长效机制

本文在探讨院务公开与治理医药购销领域商业贿赂辩证关系的基础上，从转变观念，完
善制度建设以及创造良好的医院文化等方面，提出了通过深化院务公开，建立医药购销领域长效机
制的对策和建议。     

心包内处理肺血管及心房部分切除治疗中心型肺癌

１９８７年５月至１９９３年１２月对１６例较晚期肺癌采用心包内处理肺血管及心房部分切除的方法作了全肺切除术，肿瘤均为中心型。ＣＴ扫描显示隆突下或主肺动脉窗淋巴结肿大者占５０％，术中见肺动脉，肺静脉均受累者８例，肺静脉受累者６例，２例作左心室部分切除，１５例恢复良好，１例术中大出血致心脏停搏，复苏后并发脑水肿昏迷死亡。我们认为，心包内处理肺血管全肺切除提高了手术切除率，且手术过程较安全可靠，作者对这种