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BACKGROUND CONTEXT: Several studies report a favorable short-term outcome after nonoperatively treated two-column thoracic or lumbar burst fractures in patients without neurological deficits. Few reports have described the long-term clinical and radiological outcome after these fractures, and none have, to our knowledge, specifically evaluated the long-term outcome of the discs adjacent to the fractured vertebra, often damaged at injury and possibly at an increased risk of height reduction and degeneration with subsequent chronic back pain. PURPOSE: To evaluate the long-term clinical and radiological outcome after nonoperatively treated thoracic or lumbar burst fractures in adults, with special attention to posttraumatic radiological disc height reduction. STUDY DESIGN: Case series. PATIENT SAMPLE: Sixteen men with a mean age of 31 years (range, 19-44) and 11 women with a mean age of 40 years (range, 23-61) had sustained a thoracic or lumbar burst fracture during the years 1965 to 1973. Four had sustained a burst fracture Denis type A, 18 a Denis type B, 1 a Denis type C, and 4 a Denis type E. Seven of these patients had neurological deficits at injury, all retrospectively classified as Frankel D. OUTCOME MEASURES: The clinical outcome was evaluated subjectively with Oswestry score and questions regarding work capacity and objectively with the Frankel scale. The radiological outcome was evaluated with measurements of local kyphosis over the fractured segment, ratios of anterior and posterior vertebral body heights, adjacent disc heights, pedicle widths, sagittal width of the spinal canal, and lateral and anteroposterior displacement. METHODS: From the radiographical archives of an emergency hospital, all patients with a nonoperatively treated thoracic or lumbar burst fracture during the years 1965 to 1973 were registered. The fracture type, localization, primary treatment, and outcome were evaluated from the old radiographs, referrals, and reports. Twenty-seven individuals were clinically and radiologically evaluated a mean of 27 years (range, 23-41) after the injury. RESULTS: At follow-up, 21 former patients reported no or minimal back pain or disability (Oswestry Score mean 4; range, 0-16), whereas 6 former patients (of whom 3 were classified as Frankel D at baseline) reported moderate or severe disability (Oswestry Score mean 39; range, 26-54). Six former patients were classified as Frankel D, and the rest as Frankel E. Local kyphosis had increased by a mean of 3 degrees (p<.05), whereas the discs adjacent to the fractured vertebrae remained unchanged in height during the follow-up. CONCLUSIONS: Nonoperatively treated burst fractures of the thoracic or lumbar spine in adults with or without minor neurological deficits have a predominantly favorable long-term outcome, and there seems to be no increased risk for subsequent disc height reduction in the adjacent discs.  相似文献   
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During 1984-1985, 410 patients with cervical hip fracture were randomized between 2 methods of internal fixation-a single nail (Rydell) or 2 LIH hook pins (LIH). The patients were followed-up prospectively for at least 2 years. Radiographs were taken after 1 week, 1, 3, 6, 12, and 24 months. The radiographs of the 295 paients alive 2 years postoperatively were examined by one of the authors. The sliding and the diversion of the pins and the nail in the anteroposterior projection and the diversion in the lateral projection were measured. In the failure group (non-union, late segmental collapse), the greatest sliding was noted within 1 month postoperatively and the diversion increased up to 3 months. Significant differences between the failure and the non-failure groups could be seen even after 1 week. We also found that the degree of sliding of the LIH pins and the Rydell nail 1 month postoperatively is comparable to the scintigraphic pattern 2 weeks postoperatively in predicting failure after nternal fixation of cervical hip fractures.  相似文献   
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The authors report their studies of 39 lymphoscintigraphies performed on patients with breast cancer. They point out that interpretation of scintigraphic imaging must take into account the morphologic variations of the lymph nodes of the internal mammary chains (i.e. single central chain, single central lymph node) and the morphological difference in the symmetry of lymph nodes considered non-pathologic to avoid false positives. The authors retain that lack of visualization of a chain, conspicuous increase in size of a lymph node, asymmetry of pathologic development, or reduced uptake by one or more lymph nodes of the internal mammary chains must be interpreted as a sign of metastatic spread. The authors recommend lymphoscintigraphy as an effective technique in the screening of breast cancer patients for staging, follow-up, restaging, and planning of radiotherapy.  相似文献   
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The plasmid-encoded AIDA (adhesin involved in diffuse adherence) autotransporter protein derived from diffuse-adhering clinical Escherichia coli isolate 2787 and the TibA (enterotoxigenic invasion locus B) protein encoded by the chromosomal tib locus of enterotoxigenic E. coli (ETEC) strain H10407 are posttranslationally modified by carbohydrate substituents. Analysis of the AIDA-I adhesin showed that the modification involved heptose residues. AIDA-I is modified by the heptosyltransferase activity of the product of the aah gene, which is located directly upstream of adhesin-encoding gene aidA. The carbohydrate modification of the TibA adhesin/invasin is mediated by the TibC protein but has not been elucidated. Based on the sequence similarities between TibC and AAH (autotransporter adhesin heptosyltransferase) and between the TibA and the AIDA proteins we hypothesized that the AIDA system and the Tib system encoded by the tib locus are structurally and functionally related. Here we show that (i) TibC proteins derived from different ETEC strains appear to be highly conserved, (ii) recombinant TibC proteins can substitute for the AAH heptosyltransferase in introducing the heptosyl modification to AIDA-I, (iii) this modification is functional in restoring the adhesive function of AIDA-I, (iv) a single amino acid substitution at position 358 completely abolishes this activity, and (v) antibodies directed at the functionally active AIDA-I recognize a protein resembling modified TibA in ETEC strains. In summary, we conclude that, like AAH, TibC represents an example of a novel class of heptosyltransferases specifically transferring heptose residues onto multiple sites of a protein backbone. A potential consensus sequence for the modification site is suggested.  相似文献   
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In an exploratory study, 11 common polymorphisms were examined for contributing to longevity including: apolipoprotein E (apoE), methylenetetrahydrofolate reductase (MTHFR), cathepsin D (CAD), superoxide dismutase 2 (SOD2), angiotensinogen (AGT) and insulin-like growth factor 2 (IGF2), Leiden factor 7, p53 oncogene, dopamine D4 receptor (DRD4) and the serotonin transporter (SERT). Genotype and allele frequencies of these genes were compared in 224 older (75 years) Jewish Jerusalem residents of Ashkenazi ethnicity to a group of 441 younger subjects (22 years). Nominally significant results provide suggestive evidence in the Ashkenazi group that apoE, MHTFR, SOD2, IGF2 ApaI, and factor VII are risk factors for a single outcome, survival to 75. Overall, the more genetically homogenous Ashkenazi ethnic group showed evidence for association in five genes examined suggesting that future studies in this population would gainfully focus on this ethnic group.  相似文献   
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A child with multiple anomalies, including growth retardation, a left-sided diaphragmatic hernia with lung hypoplasia, and cerebral malformations is described. Cytogenetic investigation demonstrated a deletion of the distal part of one chromosome 15, del(15)(q24qter), an aberration not previously described. Family studies revealed that the mother had a balanced translocation, t(6;15)(p25;q24). Two of her subsequent pregnancies resulted in abortions after prenatal diagnosis: one fetus was trisomic for 15q24→qter, while the other had monosomy 15q24→qter and a left-sided diaphragmatic hernia similar to the first child.  相似文献   
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Mutation spectra induced by 4-nitroquinoline 1-oxide (4NQO)at the hprt locus for both normal (AA8) and 4NQO-sensitive (UV5)Chinese hamster ovary cells were determined to investigate theeffect of DNA repair on the nature of induced mutations. TheUV5 cell line is three times more sensitive to 4NQO than theAA8 parental cell line. In UV5 cells, the dGuo-N2-AQO adduct,which is considered to be the most toxic and mutagenic adductin Escherichia coli, is poorly repaired. The molecular natureof 30hprt mutants isolated from AA8 and 20 isolated from UV5cells was determined by sequence analysis of in vitro amplifiedhprtcDNA. Both similarities and differences emerged. In bothcell lines we found that (i) 4NQO is basically a base substitutionmutagen acting almost exclusively at G residues and (ii) G transversionsare prevalent over G transitions in both cell lines, independentlyfrom the ability to repair dGuo-N2-AQO. A high proportion (13/25)of splice mutations was observed in AA8 cells, statisticallydifferent (P < 0.04, Fisher‘s exact test) from theincidence of splice mutants in UV5 cells (4/20). In AA8 mutants,all but two of the point mutations were due to lesions localizedon the non-transcribed strand, suggesting preferential repairof the transcribed strand. Compared with AA8, the proportionof mutants due to lesions present on the transcribed strandwas higher in UV5 cells, as expected if a preferential repairmechanism was impaired in the sensitive cell line. Our dataare consistent with the molecular defect in DNA repair recentlycharacterized in UV5. 3To whom correspondence should be addressed  相似文献   
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