The effects of visual scenes on roll and pitch thresholds in pilots versus nonpilots

BACKGROUND: Previous studies have indicated that, compared with nonpilots, pilots rely more on vision than "seat-of-the-pants" sensations when presented with visual-vestibular conflict. The objective of this study was to evaluate whether pilots and nonpilots differ in their thresholds for tilt perception while viewing visual scenes depicting simulated flight. METHODS: This study was conducted in the Advanced Spatial Disorientation Demonstrator (ASDD) at Brooks AFB, TX. There were 14 subjects (7 pilots and 7 nonpilots) who recorded tilt detection thresholds in pitch and roll while exposed to sub-threshold movement in each axis. During each test run, subjects were presented with computer-generated visual scenes depicting accelerating forward flight by day or night, and a blank (control) condition. RESULTS: The only significant effect detected by an analysis of variance (ANOVA) was that all subjects were more sensitive to tilt in roll than in pitch [F (2,24) = 18.96, p < 0.001]. Overall, pilots had marginally higher tilt detection thresholds compared with nonpilots (p = 0.055), but the type of visual scene had no significant effect on thresholds. CONCLUSION: In this study, pilots did not demonstrate greater visual dominance over vestibular and proprioceptive cues than nonpilots, but appeared to have higher pitch and roll thresholds overall. The finding of significantly lower detection thresholds in the roll axis vs. the pitch axis was an incidental finding for both subject groups.     

Temporal lobe necrosis in nasopharyngeal carcinoma: Pictorial essay

Nasopharyngeal carcinoma (NPC) shows a high frequency of skull base erosion and intracranial spread. This tumour is usually treated with radiation therapy. The medial and inferior portions of both temporal lobes are included within the radiation portals. These areas are therefore potential sites of radiation-induced necrosis. It is important to recognize this complication and separate it from intracranial tumour recurrence because the treatments of these entities are different.     

Consistency of microvascular and autonomic abnormalities in diabetes

The progression of early measures of microvascular disease and autonomic neuropathy were studied in a group of 81 children with insulin dependent diabetes mellitus over a mean interval of 4.2 years. Repeated measurements were made of blood pressure, albumin excretion, joint mobility, and pupillary dilatation in darkness. Over the years between the first and the second study, systolic and diastolic blood pressure showed positive tracking correlations (r = 0.38 and r = 0.32) with a small but significant deviation from normality; albumin/creatinine ratio was significantly increased (0.79 v 0.55); a greater number of children were identified in the second study as having limitation of mobility of the fifth metacarpophalangeal joint; and pupillary dilatation in darkness significantly decreased (61.5% v 62.9%); 62% of the children with one or more abnormal measurements in the first study were found to have measurements outside the normal ranges in the second study, indicating a consistency in observations over time. It remains to be seen with what accuracy these measurements predict adult onset clinical disease.     

The influence of thin-section tomography on the treatment of cervical spine injuries

A study was performed to determine the influence of routine thin-section tomography on subsequent treatment of the patient with acute trauma to the cervical spine. Of 79 such patients who underwent tomography over a 14-month period, 55 had suspicious indirect findings on the radiograph and 25% of these were shown to have fractures, while 67% of the patients without radiographic abnormalities who presented with a neurological deficit also demonstrated fractures on tomography. Of the patients who were shown to have fractures prior to tomography, 54% had more extensive injury than originally suspected. In nearly 18% of patients, the mode of therapy was changed significantly after tomographic evaluation. Indications for tomography are discussed and specific recommendations for systematic radiographic evaluation of cervical spine injuries are presented.     

转染外源性白细胞介素6基因增强乳腺癌细胞株MCF-7表达肿瘤相关抗原

目的 :探索白细胞介素 6 (interleukin 6 ,IL 6 )增强乳腺癌细胞表达乳腺癌抗原 (CA15 3)和癌胚抗原 (CEA)的作用。方法 :将含IL 6蛋白编码顺序1176bpcDNA插入Pci neo哺乳动物表达载体。将重组载体转染MCF 7乳腺癌细胞 ,采用ELASA方法测定细胞培养上清液内IL 6浓度 ,用MEIA(microp articalenzymeimmunoassay)方法测定上清液中肿瘤相关抗原CA15 3、CEA和CA12 5。结果 :含有外源IL 6基因的MCF 7细胞分泌IL 6浓度 (338.5±2 2 .6pg·10 -6细胞 )明显高于父本没有含外源基因的MCF 7细胞 (2 5 .4± 4 .6pg·10 -6细胞 )和仅含空载体Pci neo的MCF 7细胞 (19.6± 3.0pg·10 -6细胞 ) (P<0 .0 1)。细胞培养d 3后 ,带外源IL 6基因的MCF 7细胞培养上清液中CA15 3和CA12 5水平 (分别为 14 .9± 2 .3和 38.8± 5 .1μg·10 -6细胞 )明显高于父本 (分别为 6 .6± 1.5和 10 .0± 1.6 μg·10 -6细胞 )和空载体Pci neo的MCF 7细胞 (分别为 3.4±0 .7和 14 .6± 2 .2 μg·10 -6细胞 ,P <0 .0 5 )。而转染IL 6基因没有明显改变CEA表达 (P >0 .0 5 )。结论 :IL 6具有诱导肿瘤相关抗原的表达和增强肿瘤细胞的免疫原性的作用 ,提示IL 6可能增强机体对肿瘤的免疫反应性。     

Acute cervical spine trauma: evaluation with 1.5-T MR imaging

Twenty-one patients with acute neurologic deficits following cervical spine trauma were evaluated with magnetic resonance (MR) imaging (n = 21), computed tomography enhanced with intrathecal contrast material (CT myelography) (n = 18), myelography (n = 13), cervical spine radiography (n = 21), and intraoperative sonography (n = 7). MR imaging proved superior to other modalities in demonstrating parenchymal spinal cord injuries and cervical intervertebral disk herniation. Although both T1- and T2-weighted studies appear necessary to evaluate the anatomic relationship of the spinal cord, thecal space, intervertebral disks, and surrounding osseous and ligamentous structures, T2-weighted sequences were more sensitive than T1-weighted studies for detection of spinal cord injury. CT myelography was superior to MR imaging in demonstrating cervical spine fractures. In most cases, myelography revealed no information that was not apparent from both CT and MR imaging studies. Preliminary experience with MR imaging of acute cervical spine trauma suggests that it should be the study of choice in symptomatic patients who are otherwise clinically stable. CT may still be required in selected patients to evaluate complex fractures.     

股内侧肌穿支皮瓣的解剖学基础与膝周创伤修复

目的:探讨股内侧肌穿支皮瓣的解剖学特征,为临床膝周软组织缺损的修复提供一种新的术式。方法:实验于2005-01/10在解放军南京军区福州总医院军区临床解剖学研究中心实验室完成。30侧动脉内灌注红色乳胶的成人下肢标本由南京军区福州总医院军区临床解剖学研究中心提供。30侧成人下肢标本,以收肌结节、髌骨中点、腹股沟韧带中点为观测标志,重点解剖观测股内侧肌肌支的起源、走行、分支、分布及其远端吻合情况。一侧新鲜标本上,摹拟术式设计。结果:在股三角尖部自股动脉恒定发出的股内侧肌支,入肌门后在肌内沿肌束行向外下方,直至髌旁并与髌周动脉环相吻合。沿途除发出肌支营养股内侧肌外,还发出1～3支(77%为1支)、外径0.5～0.9mm肌皮穿支垂直穿过股内侧肌达深筋膜,并浅出至股内侧肌表面皮肤。皮瓣切取面积可达8.5cm×15.0cm。结论:可形成的以股内侧肌肌支-穿支逆行皮瓣转位可修复膝部软组织缺损。     

Cost-effectiveness of collaborative care for the treatment of major depressive disorder in primary care. A systematic review

Background  

The effectiveness of collaborative care for patients with major depressive disorder in primary care has been established. Assessing its cost-effectiveness is important for deciding on implementation. This review therefore evaluates the cost-effectiveness of collaborative care for major depressive disorder in primary care.     

阿司匹林锌的研制(Ⅰ)

研究阿司匹林锌的化学合成方法。方法：以阿司匹林和硫酸锌为原料,经两步反应合成阿司匹林锌。结果得到的样品经ＩＲ、ＮＭＲ、ＭＳ等波谱分析及元素分析、热分析证明该化合物为阿司匹林锌。总收率为８０％。结论该合成方法收率稳定,合成周期短,合成路线完全可行。