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1.
Summary This report deals with a case of rhabdomyosarcoma in the upper thoracic spine. It is of particular interest, not only for the rarity of type and location of this tumour, but for its clinical course, which presented fluctuations of neurological status, included an acute demonstration of complete paraplegia followed by full recovery after conservative treatment, and gradual relapsing of neurological deficit, one year later.  相似文献   
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AStudyonExtension-FlexionDynamicLumbarSpineRadiographsinPatientswithLumbarIntervertebralDiscHerniationAStudyonExtension-Flexi...  相似文献   
4.
Summary From 1987 to 1990 the authors treated 20 cases of spondylolisthesis by an improved operative procedure including excision of the medial part of the superior articular processes of the slipped vertebra, excision of the soft tissue between the ununited isthmi, and excision of the ligamentum flavum between the intervertebral space above the slipped segment. In some instances the lower portion of the lamina over the slipped vertebra should be resected. A U-shaped rod was used to hold sublaminar fixation of two segments above and below the slipped vertebra, with the slipped vertebra spared. Utilizing the U-shaped rod as support, bone strips were placed along the lateral and anterior sides of the rod to bridge the gap between the laminae of the displaced vertebra. Other bone grafts were focused on the facet joints. The patients were allowed ambulation early postoperatively. 19 cases could be evaluated at preliminary follow-up. All showed satisfactory results.  相似文献   
5.
Sibling subspecies of Dundocoris nodulicarinus, inhabiting different isolated indigenous evergreen forests in South Africa, have chromosome numbers of 2n(male) = 14XY, 9XY1Y2 and 7XY1Y2. The ancestral chromosome number of Dundocoris is probably 2n(male) = 28XY and several chromosome fusions were involved in the karyotype evolution of these taxa. The XY1Y2 sex chromosome system of the 9XY1Y2 D. nodulicarinus novenus originated by the fusion of a large autosome with the X-chromosome, forming a neo-X with the homologue of the fused autosome forming the neo-Y (=Y1) and the original Y-chromosome, the Y2. While the original X- and Y-chromosomes are heterochromatic and heteropycnotic during prophase I, the autosomal part of the neo-X and the neo-Y stay euchromatic and behave like a normal autosomal pair, forming synapsis and chiasmata. The XY1Y2 sex chromosome system of the 7XY1Y2 D. nodulicarinus septeni probably originated from the 9XY1Y2 karyotype when the homologous chromosomes of a small autosomal pair fused with the original X- and Y-chromosomes, respectively. In both the subspecies with the neo-XY1Y2 systems, the original sex chromosomes still undergo chromatid segregation at anaphase I (= post-reductional). The evolution and behaviour of the karyotypes and sex chromosome systems during the course of meiosis in the subspecies of D. nodulicarinus are described, discussed and illustrated.  相似文献   
6.
A prospective study in 31 patients was designed to compare contrast quantitatively using axial conventional, gated spin-echo T2-weighted (T2W) (SE) (asymmetrical echo TE 30 and 80 ms) and axial dual-echo fast spin-echo (FSE) sequences (TEeff20 and 120 ms) to image lumbar discs, nerve roots, and cerebrospinal fluid CSF. We used two quantitative measures, percent (%) contrast and contrast-to-noise ratio (CNR), to compare the sequences. The FSE sequence had greater % contrast and CNR on the first and second echo images for both disc and nerve root detection using these scan parameters. An axial FSE sequence, therefore, provided contrast characteristics similar to those of gated axial T2W SE sequence in the lumbar spine, with a 60% saving in acquisition time. The FSE sequence is now our standard axial T2W study for the lumbar spine.  相似文献   
7.
Eight female volunteers received acute doses of amitriptyline 50 mg (AMI), dothiepin 50 mg (DOT), fluoxetine 40 mg (FLU) or placebo both with and without a ‘social’ dose of alcohol (ALC) equivalent to 0·5 g/kg body weight absolute alcohol. Performance on a variety of tests of psychomotor ability and cognitive function (critical flicker fusion, choice reaction time, tracking, Maddox Wing and simulated car steering) were performed at 1·5 and 4 hours following treatment. AMI and DOT both with and without ALC impaired performance on a range of tests at either or both 1·5 and 4 hours, although the effects of AMI and AMI + ALC were more widespread and severe than those found with either DOT or DOT + ALC. FLU and FLU + ALC showed no evidence of impairment on any test at either the 1·5 or the 4 hours assessments. The results suggest that there are differences between the experimental substances, at the doses used, in their intrinsic potential for impairing aspects of psychomotor performance and cognitive function.  相似文献   
8.
Emergency airway management in patients with cervical spine injuries   总被引:10,自引:0,他引:10  
J. C. Criswell  FRCA  M. J. A. Parr  MRCP  FRCA    J. P. Nolan  FRCA 《Anaesthesia》1994,49(10):900-903
  相似文献   
9.
Paramyxoviruses of type 1 (PMV-l) isolated from pigeons were genetically analyzed. A part of the fusion and the matrix protein genes were amplified and sequenced, Typical amino acid sequences associated with virulence were determined at the fusion protein cleavage site in all PMV-1 isolates. All Slovene pigeon PMV-1 strains share high amino acid sequence similarity with other pigeon strains. In the phylogenetic tree, they are clustered together with pigeon PMV-1 isolates with moderate pathogenicity. Phylogenetic analysis obtained from the fusion and the matrix protein gene alignments showed the same branching order. Viruses circulating among pigeons were found to form quite unique lineage of virulent NDV strains.  相似文献   
10.
Targeted recombination was carried out to select mouse hepatitis viruses (MHVs) in a defined genetic background, containing an MHV-JHM spike gene encoding either three heptad repeat 1 (HR1) substitutions (Q1067H, Q1094H, and L1114R) or L1114R alone. The recombinant virus, which expresses spike with the three substitutions, was nonfusogenic at neutral pH. Its replication was significantly inhibited by lysosomotropic agents, and it was highly neuroattenuated in vivo. In contrast, the recombinant expressing spike with L1114R alone mediated cell-to-cell fusion at neutral pH and replicated efficiently despite the presence of lysosomotropic agents; however, it still caused only subclinical morbidity and no mortality in animals. Thus, both recombinant viruses were highly attenuated and expressed viral antigen which was restricted to the olfactory bulbs and was markedly absent from other regions of the brains at 5 days postinfection. These data demonstrate that amino acid substitutions, in particular L1114R, within HR1 of the JHM spike reduced the ability of MHV to spread in the central nervous system. Furthermore, the requirements for low pH for fusion and viral entry are not prerequisites for the highly attenuated phenotype.  相似文献   
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