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991.
992.
Three-dimensional spinal curvature in idiopathic scoliosis 总被引:3,自引:0,他引:3
Scoliosis is usually considered as a deformity of the spine in the frontal plane, without reference to curvatures in other planes. In this study, the three-dimensional shape of the spine of 104 patients with untreated idiopathic scoliosis (5-55 degrees Cobb) was studied by means of stereo radiographs to determine relationships between curvature of the spine in the frontal plane view, in the lateral view, and in the intermediate views. There was a weak but statistically significant correlation (r = 0.2) relating greater scoliosis with lesser kyphosis or greater lordosis. In the thoracic region, the sagittal plane spinal curvature was less than that measured in a population without scoliosis (mean difference, 7.72 +/- 9.9 degrees). Seventy-four of 76 scolioses in the upper region of the spine with lateral curvature greater than 5 degrees Cobb were kyphotic. Sixty-four of 84 curves greater than 5 degrees Cobb in the lower region were lordotic. Measuring curvatures in the plane of symmetry of the rotated apical vertebra altered these ratios to 69 of 76 kyphotic in the upper region and 68 of 84 lordotic in the lower region. The plane of maximum curvature of sections of the spine with scoliosis was not related to the plane of symmetry of the rotated apical vertebra, for in kyphotic regions of the spine the rotations of these two planes were in opposite directions. In all cases, the magnitudes of the rotations were quite different, i.e., by a factor of -0.22 for curves in thoracic region and by a factor of 0.24 for curves in the lumbar region. This implies that mechanical measures to correct this spinal deformity or to prevent progression should apply different rotations to the apex from those applied to the curve as a whole and, in opposite senses, in curves in kyphotic regions. There was no evidence of an abnormality of sagittal curvature of a magnitude to implicate it in the etiology or in the treatment. 相似文献
993.
Predicting failure in polytetrafluoroethylene vascular access grafts for hemodialysis: a pilot study
C R Shackleton D C Taylor A R Buckley V A Rowley P L Cooperberg P D Fry 《Canadian journal of surgery》1987,30(6):442-444
In order to determine if serial, noninvasive evaluation of polytetrafluoroethylene (PTFE) vascular access grafts could identify a subgroup of patients at risk for thrombosis, the authors studied flow characteristics, using duplex ultrasonic scanning, in 18 hemodialysis patients with forearm loop grafts. On average, five examinations were performed per patient over the 10-month study period. Seven episodes of thrombosis occurred in six patients. The mean Doppler flow in grafts that subsequently thrombosed was significantly lower than in those that did not (544 +/- 218 ml/min versus 843 +/- 391 ml/min, p less than 0.001). The interval from last examination to thrombosis ranged from 13 to 58 days. At a defined cut-off flow of 450 ml/min, this test yielded a sensitivity of 83% and a specificity of 75% for episodes of thrombosis occurring within 2 to 6 weeks. The authors conclude that episodes of thrombosis in PTFE arm loop grafts are usually preceded by significantly lower Doppler-measured flow than grafts that do not thrombose and that it may be possible, by this means, to identify grafts at risk. 相似文献
994.
Rotator interval lesion 总被引:5,自引:0,他引:5
Arthrography and surgical exploration reveal the pathogenesis of a painful shoulder syndrome characterized by inferior instability in the rotator interval (RI). The RI is the space between the subscapularis and the adjacent supraspinatus interval. Two types of RI lesions can be identified. Type I, a contracted state, is characterized by inflammatory changes in superficial bursal area. In Type II, an unstable condition is associated with extensive inflammation of deeper tissues in the RI. In a series of 101 patients, including 106 shoulders with RI lesions, surgical repair of the RI was performed with the shoulder in an externally rotated position. This position ensured a close fit of the supraspinatus and the subscapularis attachments. Of 78 shoulders evaluated in a follow-up study, 96% were graded good or excellent, and 4% poor. This investigation presents evidence for the importance of diagnosis and treatment of RI lesions in patients with persistent pain in the shoulder. 相似文献
995.
EVA ÅKERLÖF B. FREDRICSON O. GUSTAFSSON A. LUNDIN† N. O. LUNELL L. NYLUND L. ROSENBORG Å. POUSETTE 《International journal of andrology》1987,10(5):663-669
Two methods of separating human sperm were compared using twenty-two semen samples. The sperm were separated by a swim-up technique or by self-migration on a Percoll gradient followed by medium change. After separation, the sperm obtained were assessed for progressive motility, ATP content, energy charge index ([ATP + 0.5 ADP]/[ATP + ADP + AMP]) and morphology. In general, and especially for semen samples containing less than 20 X 10(6) sperm/ml, separation by Percoll gradient selected sperm that were superior to those separated by the swim-up technique. The relatively high energy charge index (greater than 0.8) showed that the sperm tolerated the separation conditions well. It is suggested that self-migration on a Percoll gradient should prove useful for obtaining sperm of high quality. 相似文献
996.
Platelet Aggregation Inhibiting and Anticoagulant Effects of Oligoamines, VII: Benzene-1,3,5-trialkanamines Seventeen title compounds were synthesized. Platelet aggregation induced by collagen in vitro is inhibited by 9 of them at IC50 = 2–4 μmol/L. Seven compounds depress the formation of fibrin to ≦ 25 % of normal in concentrations below 50 μmol/L. Compound 15 [4-(2-thienylbutyl)benzene-1,3,5-trimethanamine is the first oligoamine which shows anticoagulant and antiplatelet effects at the same concentration (25 μmol/L). 相似文献
997.
J.K. MOHANA RAO 《Chemical biology & drug design》1987,29(2):276-281
Based on residue characteristic physical parameters, a new scoring matrix, called EMPAR, for amino acid exchanges in proteins was obtained. When comparing protein sequences for detecting homologies, the use of this matrix in place of the Dayhoff log-odds matrix yields results that reflect the topological similarities in the proteins. The use of EMPAR is equivalent to the parametric correlation coefficient approach of Ooi and his colleagues. This matrix correlates at 0.63 with the Dayhoff matrix. 相似文献
998.
Gamma-glutamyl transpeptidase (GGT) activity has been demonstratedhistochemically in a number of experimentally induced neoplasmsand has been suggested as a label for potential precursors forthe development of squamous cell carcinomas. This study exploresthe kinetics of GGT-stained cell populations, their correlationwith the hypothesized initiated cells and evidence of malignanttransformation of epithelium in hamster buccal pouch by a 15-weekregime of tri-weekly topical application of 7,12-dimethylbenz[a]anthracene(DMBA) in mineral oil. GGT-positive foci were detected histochemicallyin tissue sections as early as 1 week after application of thecarcinogen, when there was no morphological evidence of dysplasia.The average number of the GGT-positive foci in each experimentalperiod was found to increase with time. Even though the majorityof the foci were small, consisting of only a single cell ora small group of cells, a few larger GGT-positive lesions werenoted, particularly in the later period of the experiment. Atotal of 66 grossly visible neoplasms were found. Thirty-sevenof these were submitted for GGT staining. Thirty-two (86.5%)of these showed patchy GGT activity, primarily in the superficialepithelial cells and/or the keratin. In the non-neoplastic epithelium,the GGT staining could involve any or all layers of cells. GGTactivity was not detected in untreated or mineral oil-treatedmucosa. The results of this study support the hypothesis thatGGT activity may label potential precursors for the developmentof squamous cell carcinomas. 相似文献
999.
S. MD. Iqbal A. K. Garg C. M. Kalaiah 《Indian journal of otolaryngology and head and neck surgery》1987,39(1):38-39
A case of Goldenhar’s Syndrome in a 10 year old girl is reported. The unusual features are the absence of epibulbar dermoid which is one of the major hallmarks of the Syndrome and the presence of an associated Cyanotic Heart disease. 相似文献
1000.
J L Schrader 《The American journal of psychiatry》1987,144(1):107-109
The Alaska mental health program is endowed with a 1-million-acre trust fund. A coalition of groups that make up the mental health constituency of the state united in a lawsuit to establish the trust. The history of this legacy, the struggle to realize its benefits, its current status, and some of its psychopolitical significance are discussed. 相似文献