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141.
A cost analysis of two anterior cervical fusion procedures 总被引:5,自引:0,他引:5
Multilevel anterior cervical discectomy and fusion (ACDF) remains a difficult problem. A recently described surgical technique for multilevel ACDF has eliminated the morbid complications associated with harvesting iliac crest bone graft (ICBG) while maintaining the advantages of using autologous bone graft. A matched-pairs t test was used to compare the estimated costs of 27 ACDFs using titanium surgical mesh, local autologous bone graft, and anterior plate instrumentation with 27 ACDFs using ICBG and plate fixation. The three variables considered were cage cost, operating time (cost), and hospitalization cost. The estimated costs for the two surgical procedures were not significantly different. Thus, the time saved by not harvesting an ICBG was comparable to the cost of the cage. Harvesting ICBG also increased the morbidity rate by 22%. 相似文献
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Depression and trauma are common among women living with HIV. This is the first study to track the longitudinal course of depression and examine the relationship between depression and trauma over time among women in South Africa. HIV-infected and uninfected women (N = 148) were assessed at baseline and one year later. Results of a path analysis show the multi-directional and entwined influence of early life stress, other life-threatening traumas across the lifespan, depression and PTSD over the course of HIV. We also observed higher rates of depressive symptomatology and more persistent cases among infected women compared to uninfected women, as well as a more consistent and enduring relationship between childhood trauma and depression among women living with HIV. The present study is unique in documenting the course of untreated depression and PTSD in women with and without HIV infection with a high prevalence of early childhood trauma. 相似文献
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Streptococcus mutans Genes That Code for Extracellular Proteins in Escherichia coli K-12 总被引:8,自引:22,他引:8 下载免费PDF全文
Robert G. Holt Yoshimitsu Abiko Shigeno Saito Maryla Smorawinska Jeffrey B. Hansen Roy Curtiss III 《Infection and immunity》1982,38(1):147-156
Chromosomal DNA from Streptococcus mutans 6715 (serotype g) was cloned into Escherichia coli K-12 by using the cosmid pJC74 cloning vector and a bacteriophage λ in vitro packaging system. Rabbit antiserum against S. mutans extracellular proteins was used for immunological screening of the clone bank. Twenty-one clones produced weak to strong precipitin bands around the colonies, but only after the λ c1857 prophage was induced by being heated to lyse the E. coli cells. None of the clones expressed enzyme activity for several known S. mutans extracellular enzymes. One of these clones contained a 45-kilobase recombinant plasmid designated pYA721. An 8.5-kilobase fragment of S. mutans DNA from pYA721 was isolated and recloned into the BamHI restriction site of the plasmid vector pACYC184 to construct pYA726. pYA726 contained all, or nearly all, of the gene for a surface protein antigen (the spaA protein) of S. mutans 6715. This was deduced from immunological studies in which extracts of cells harboring pYA726 reacted with antisera against both purified 6715 spaA protein (about 210,000 daltons) and the immunologically similar antigen I/II of serotype c strains of S. mutans. In addition, the S. mutans spaA protein was found to possess at least one antigenic determinant not present on the protein specified by pYA726. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of E. coli clone extracts revealed that pYA726 produced a polypeptide with a molecular mass of about 180,000 daltons which was predominantly found in the periplasmic space of E. coli cells. Antisera to the spaA protein of S. mutans reacted with extracellular protein from representative strains of S. mutans serotypes a, c, d, e, f, and g, but not b. 相似文献
150.
Writing epilepsy is a rare reflex syndrome in which seizures are triggered by writing. We describe a 33-year-old, right-handed man, with a history of juvenile absence epilepsy in remission and a family history of epilepsy, in whom myoclonic jerks precipitated exclusively by writing started at the age of 30. Intensive video/EEG monitoring during neuropsychological tests revealed, at about 1 minute after starting to write, a dystonic posture, followed by myoclonic jerks involving the right hand that shortly after became generalized. Concomitantly, the ictal EEG documented generalized hypersynchronous polyspike-wave discharges, maximal over the right parietocentral area. SPECT revealed an ictal hyperperfusion and interictal hypoperfusion over right parietofrontal regions, and fMRI showed extensive and intense left frontal, supplementary motor area activation, induced by writing. This case study provides some evidence supporting the hypothesis that the mechanism underlying writing-triggered seizures may be a generalized seizure process, with a focal cortical trigger zone, presumed to be the left frontal lobe as suggested by clinical and fMRI data. A relevant role played by the right hemisphere (right parietofrontal region) is postulated in the full-blown expression of reflex epileptogenesis, as supported by EEG and SPECT findings. 相似文献