Background: The purpose of this study was to analyze the position of the conus medullaris and Tuffier's line in the same patient population, to correlate this position with age and sex, and to determine an objective guide for the selection of a safe intervertebral space during spinal block.
Methods: Magnetic resonance imaging studies of the lumbar spine were reviewed in 690 consecutive patients. The study population consisted of patients older than 20 yr who had been referred for imaging to assess possible causes of low back pain. The position of the conus medullaris was defined as the most distal point of the cord that could be visualized on the sagittal sequence. A line perpendicular to the long axis of the cord was extended to the adjacent vertebra. In the lumbar plain films, the Tuffier's line was defined by drawing a horizontal line across the highest points of the iliac crests. Each vertebral body and intervertebral space was divided into four segments: upper, middle, and lower thirds of a vertebral body, and the intervertebral space. Each segment of a vertebral body or intervertebral space that the lines crossed was identified and recorded. The positions, stratified by decade of age, were compared using analysis of variance. The Tukey test was used for post hoc comparisons. Comparisons between sex were performed with the unpaired t test.
Results: The conus medullaris and Tuffier's line (median [range]) were positioned at L1-lower (T12-upper-L3-upper) and L4L5 (L3L4-L5S1), respectively. The distance between the conus medullaris and Tuffier's line (mean +/- SD [range]) was 12.6 +/- 1.9 [7-18] segments, which corresponded to the height of approximately three vertebral bodies and intervertebral spaces. In no case did Tuffier's line overlap with the conus medullaris. The distance in segments between the conus medullaris and Tuffier's line was shorter with increased age (P < 0.001). The position of the conus medullaris and Tuffier's line was lower in female patients than in male patients (P < 0.001) and higher in patients with sacralization than in those with lumbarization or without transitional vertebra (P < 0.001). The in-between distances were not significantly different regardless of sex or presence of transitional vertebra. 相似文献
Targeted mutagenesis of the retinoic acid receptor alpha (RAR alpha) gene has revealed its essential role in spermatogenesis. Although cells in all stages of spermatogenesis were detected in RAR alpha(-/-) testes, there was an increase in degenerating pachytene spermatocytes and a temporary developmental arrest in step 8-9 spermatids in the first wave of spermatogenesis, a delay in the onset of the second wave, and a temporary arrest in preleptotene to leptotene spermatocytes in the first, second, and third waves. A striking aspect of the mutant phenotype was the failure of spermatids to align at the tubular lumen at stage VIII. Furthermore, there were missing or decreased numbers of the predicted cell types in tubules, and they exhibited a profound asynchrony of mixed spermatogenic cell types. In vivo bromodeoxyuridine labeling revealed a significant decrease in germ cell proliferation in both juvenile and adult RAR alpha(-/-) testes and confirmed the arrest at step 8-9 spermatids. Retinoid signaling through RAR alpha, thus, appears to be critical for establishment of synchronous progression of spermatogenesis and the subsequent establishment of correct cellular associations. 相似文献
Measurement of spinal cord evoked potentials (SCEPs) is proposed as a means of predicting locomotion outcome in the rat spinal cord injury (SCI) model. Using 55 rats, three reproducible peak waves (waves I, II and III) were observed during stimulation at the C7 level with recording at the L1 epidural space. Hemisection at the T13 level showed three wave loss patterns: wave III loss only, loss of both wave II and III, and loss of all three waves. Defining an ideal SCI model as establishment of stable monoparesis or paraparesis, all animals in the wave II-III loss group showed favorable results. Histological data and electrophysiological properties allowed reasonable assumptions of wave origin: wave I from extrapyramidal tracts, wave II from the ventral corticospinal tract, and wave III from the dorsal corticospinal tract. Complete destruction of pyramidal tracts in both dorsal and ventral fibers was essential for long-term impairment of locomotion. 相似文献
Recessive dystrophic epidermolysis bullosa (RDEB) is an uncommon and severe disorder characterised by trauma-induced blisters, intractable skin ulcers, scarring, milia, and nail dystrophy. We report the good result of both surgical release of fingers allowing spontaneous epithelisation without skin grafting and post-operative meticulous skin care without splinting, followed-up for one year. 相似文献
OBJECTIVE: To evaluate the findings of computed tomography (CT) and histopathology of the bulla ethmoidalis as objective markers of bone remodeling in chronic rhinosinusitis (CRS). METHODS: Preoperative ostiomeatal unit (OMU) scans and histopathologic findings of the bulla ethmoidalis were performed on 23 patients (39 sides) undergoing endoscopic sinus surgery for CRS. Lund-Mackay scores and Hounsfield units (HU) of the bulla were checked in coronal CT scans. The pathologist graded the severities of the mucosal and bony changes in histopathology. Statistical analysis was performed using Mann-Whitney U test and Spearman correlation coefficient (r). RESULTS: The HU values of the bulla were significantly increased with higher Lund-Mackay scores in OMU CT (r = 0.405, P = 0.01). The bony grades in histopathology were significantly increased with higher mucosal grades (r = 0.821, P = 0.0001). These findings in CT scans and histopathology were well correlated with each other (r > 0.3, P < 0.05). CONCLUSION: HU may be a useful objective marker of bone remodeling in chronic rhinosinusitis. 相似文献
Chronic/relapsing experimental allergic encephalomyelitis (CREAE) serves as an animal model for relapsing/remitting multiple sclerosis. Treatment with the β-adrenergic agonist isoproterenol or the β2-adrenergic agonist terbutaline significantly suppressed both the first acute attack and the number of relapses in CREAE Lewis rats. The number of relapses was decreased even when treatment with β-adrenergic agonist was started after the onset of the first acute attack of CREAE. β-adrenergic receptor number was increased significantly on splenocytes from CREAE rats as compared to healthy controls or CFA-injected rats. Terbutaline treatment of CREAE rats lowered the splenocyte receptor number to normal values. 相似文献
The hexane extract from Nutmeg, the seed ofMyristica fragrans significantly inhibited hepatic drug-metabolizing enzyme activity. Through systematic fractionation by SiO2 column and vacuum liquid chromatography monitoring by bioassay, three components, myristicin, (I), licarin-B(II) and dehydrodiisoeugenol(III) were isolated as active principles. Compounds II and III, with a single treatment (200 mg/kg, i.p.) showed not only a significant prolongation of hexobarbital-induced sleeping time but also a significant inhibition of aminopyrine N-demethylase and hexobarbital hydroxylase activities in mice. Compounds I and II provoked a sleep episode at a subhypnotic dose of HB, suggesting that they posses CNS-depressant properties. 相似文献
A sensitive and simplified HPLC assay of fluconazol is described. The calibration curve of fluconazol in plasma ranging 0–10 μ g/ml was linear with the correlation coefficients of 0.9900. The limit of detection was 0.3 μ g/ml. The average recovery of the drug was 89.1±9.05%. After oral administration of single dose(150mg) of fluconazol in man, Cmax and Tmax were 3 μg/ml and 4hr., respectively. 相似文献
Compared with conventional, routine blood pressure measurement in the outpatient department of a hospital, 24-hour blood pressure monitoring provides more comprehensive information about blood pressure values in day-to-day life of the hypertensive patient. The hospital setting with all its stimuli affects the hypertensive patients so that their values will be statistically significantly higher compared with normal ones. Recent years have seen the introduction into clinical practice of self-monitoring by the patients themselves. Comparison of these three methods for blood pressure measurements revealed that self-monitoring may provide fairly accurate values comparable with those obtained by the "standard method", i.e., 24-hour monitoring. In view of the low variability of the mean value of blood pressure over a period of several days, self-monitoring can be employed in groups of selected outpatients on long-term follow-up. 相似文献
Elevated levels of the calcium-binding protein S100A4 cause metastasis of benign rat mammary tumor cells. To investigate whether S100A4 plays an important role in the invasion and metastasis of gastric cancers, we examined the gene mutations in the coding regions and expression patterns of the S100A4 in gastric adenocarcinoma in Korea. Moderate to strong expression of S100A4 was found in 53 (68.8%) of the 77 gastric adenocarcinomas, whilst normal gastric epithelium either failed to stain or showed weak staining. Interestingly, S100A4 expression was more frequently observed in gastric cancer patients with advanced gastric cancer (p=0.039), positive lymph node metastasis (p=0.001), and peritoneal dissemination (p=0.022). No gene mutations were found in the analyzed genomic area in 77 gastric adenocarcinomas and 15 gastric cancer cell lines. We found one single nucleotide polymorphism without an amino acid change, A99G, in two cases. These data suggest that the overexpression of S100A4 may be closely related to the aggressiveness of gastric cancer in Korea. 相似文献