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To date, the delineation of the human visual “motion area” still relies on functional paradigms originally devised to identify monkey area MT. Using fMRI, we have identified putative human area V5/MT+ in normals by modelling the BOLD responses to alternating radially moving and stationary dot patterns. Functional activations were compared with cytoarchitectonic probability maps of its putative correlate area hOc5, which was calculated based upon data from histological sections of ten human post-mortem brains. Bilateral visual cortex activations were seen in the single subject dynamic versus stationary contrasts and in the group random-effects analysis. Comparison of group data with area hOc5 revealed that 19.0%/39.5% of the right/left functional activation was assigned to the right/left hOc5. Conversely, 83.2%/53.5% of the right/left hOc5 was functionally activated. Comparison of functional probability maps (fPM) with area hOc5 showed that 28.6%/18.1% of the fPM was assigned to hOc5. In turn, 84.9%/41.5% of the area hOc5 was covered by the respective fPM. Thus, random-effects data and fPMs yielded similar results. The present study shows for the first time the correspondence between the functionally defined human V5/MT+ and the post-mortem cytoarchitectonic area hOc5.  相似文献   
44.
Intraabdominal postoperative or posttraumatic infections remain a major threat to life in spite of generation after generation of increasingly effective antimicrobial drugs indicating the importance of immunological host defense failure following major trauma or surgical complications. The spectrum of infectious postoperative or posttraumatic complications can, in part, be explained by pathogenic factors inherent to the methodology of modern surgical intensive care and techniques. This report presents a survey of the historical background as well as current concepts of the multiple systems organ failure syndrome as related to postoperative or posttraumatic intraabdominal infectious complications. The pathophysiology of nosocomial infectious complications in the intensive care unit setting is analyzed. The concept of gut origin sepsis is presented and possible preventive and therapeutic actions discussed. A judicious use of antimicrobial drugs on strict indications is emphasized as is the importance of increased knowledge of the interactions between the gut flora, antibiotics, and absence of enteral nutrition.
Resumen Las infecciones intraabdominales postoperatorias o postraumáticas siguen representando una amenaza grave para la vida a pesar de generación tras generación de drogas antimicrobianas de creciente efectividad, lo cual señala la importancia de la falla de los mecanismos inmunes de defensa del huésped que se presenta después de trauma mayor o acompanando las complicaciones quirúrgicas. El espectro de las complicaciones infecciosas postoperatorias o postraumáticas puede ser explicado en parte por factores patogénicos inhérentes a la tecnología y metodología del moderno cuidado intensivo del paciente en estado crítico. El presente informe reporta una revisión de los antecedentes históricos y de los conceptos actuales sobre el sindrome de falla orgánica multisistémica relacionado con complicaciones infecciosas intraabdominales postoperatorias o postraumáticas. Se analiza la patofisiología de las complicaciones infecciosas nosocomiales en el marco de la unidad de cuidado intensivo. Se hace énfasis sobre el uso juicioso de drogas antimicrobianas según indicaciones estrictas, asi como sobre la importancia de un mayor conocimiento sobre las interacciones entre la flora intestinal, los antibióticos, y la ausencia de nutrición enterai.

Résumé Les infections intra-abdominales postopératoires ou post-traumatiques continuent de menacer le pronostic vital malgré une amélioration constante des antibiotiques ce qui met l'accent sur l'échec des moyens de défense immunologiques après les traumatismes majeurs ou les complications chirurgicales. Le spectre des complications infectieuses postopératoires ou post-traumatiques peut, en partie, être expliqué par des facteurs pathogéniques inhérents à la méthode des soins intensifs et techniques modernes. Ce travail présente l'historique et les concepts actuels de défaillance polyviscérale en rapport avec des complications infectieuses intra-abdominales postopératoires ou post-traumatiques. La pathophysiologie des complications infectieuses nosocomiales dans l'unité des soins intensifs est analysée. La conception de sepsis d'origine intestinale est présentée et les actions préventive et thérapeutique sont discutées. L'utilisation judicieuse des antibiotiques est soulignée, ainsi que les interactions entre la flore intestinale, les antibiotiques et l'absence de nutrition entérale.
  相似文献   
45.
Thoracoscopic interventions in deformities of the thoracic spine   总被引:2,自引:0,他引:2  
AIM OF THE STUDY: We prospectively studied 9 patients with deformities of the thoracic spine who underwent thoracoscopic surgery to critically evaluate the benefits and limitations of thoracoscopy. METHODS: Seven patients with deformities of the thoracic spine (5 scoliosis, 2 kyphosis) underwent a thoracoscopic release and posterior correction and fusion in a single stage. In one case of a crankshaft-phenomenon a thoracoscopic epiphyseodesis und in another case of a posttraumatic kyphosis a thoracoscopic instrumentation and fusion were performed. The average age was 21 years, the follow-up was 18 months with a minimum of 12 months. The perioperative data including complications were collected and a radiographic analysis concerning curve correction was carried out. RESULTS: The scoliotic curves measured preoperatively 84 degrees on average with a Cobb angle of 62 degrees on the traction films and were corrected by 57% to averagely 36 degrees at follow-up. In the two cases of Scheuermann kyphosis a preoperative kyphosis of 94 degrees respectively 82 degrees was corrected to 52 degrees respectively 58 degrees. Between 4 and 5 discs were excised with an average operative time of 160 min and a blood loss of 380 ml. A conversion to open thoracotomy was not necessary in any case. There were no intraoperative neurovascular complications. CONCLUSIONS: Thoracoscopic procedures in deformities of the thoracic spine are technically demanding; however, it is a minimally invasive procedure with a reduced approach-related morbidity compared to open thoracotomy. The indications for a thoracoscopic release are rigid kyphosis and scoliosis with rigid curves between 80 and 90 degrees Cobb angle in which an anterior correction and instrumentation alone is not considered.  相似文献   
46.
Retinal function can be documented noninvasively and objectively by electroretinography, complementing clinical examinations. Symptoms of nightblindness and of dayblindness with photoaversion, nystagmus, poor vision in infants or unclear visual field defects are meaningful indications for ERG testing. We use standardized (ISCEV) full-field single flash ERGs to evaluate the function of the rod- and of the cone-system. In infants, general anesthesia is useful to combine an abbreviated ERG protocol with ophthalmoscopy and fundus photography. ERG testing facilitates to distinguish between functional deficits in the rod- and cone-system, between congenital-stationary retinal dysfunction and progressive retinal heredo-degenerations. Frequently a functional deficit of the retina without ophthalmoscopic changes can be assessed. These entities include achromatopsia, congenital stationary night blindness, early stages of retinitis pigmentosa (RP) or progressive cone dystrophy, as well as toxic retinal changes. Congenital amaurosis Leber (LCA), infantile RP, Usher's syndrome and retinal involvement in other neuropediatric or metabolic syndromes can be diagnosed or excluded by ERG recording early-on. Synoptic evaluation of the full-field ERG, pattern-ERG and VEP completes neuro-ophthalmological screening.  相似文献   
47.
The glucose concentration (gl) in mammalian serum incorporates a normal range of variation of several millimoles. We studied the effects of such variations on light-evoked electrical signals in the in vitro arterially perfused cat eye, avoiding extraocular regulatory mechanisms that might confound data interpretation. Changes in gl from the nominal control value of 5 mmol/l were maintained for 5-40 min. Stimuli of near rod threshold intensity were presented in full dark adaptation, and stimuli of higher intensity were presented in the presence of a white background for cone responses. We recorded the dc-electroretinogram (ERG), the scotopic threshold response (STR), the optic nerve response (ONR), and the transretinal slow P-III and transepithelial retinal pigment epithelium c-wave from the subretinal space. The ocular standing potential changed by up to +/- 2 mV in parallel with an increase and decrease in gl, independent of the adaptation condition. Our results show that the rod-ERG, STR, and rod-driven optic nerve response (ONR) have a marked sensitivity to small changes in gl (+/- 1 to 3 mmol/l). The field potentials increased and decreased in parallel with changes in gl. The cone ERG and cone ONR, in contrast, failed to respond consistently to increases in gl and revealed decreases in amplitudes only with an extreme decrease in gl. Decrease in gl, down to 2 mmol/l and less, is known to induce drastic behavioral and electrophysiologic phenomena in the central nervous system. Our results imply that the "normal" glucose level, at least in the cat, could be marginal for rod-mediated retinal function. The results also suggest a marked difference in metabolic mechanisms for cone versus rod photoreceptors.  相似文献   
48.
We report the association a multiple sclerosis (MS), spinal cord tumour and intracranial tumor in a 63 years-old female patient with a 10 years history of relapsing/remitting MS. Symptoms usually remitted in response to costicosteroid therapy. In 1997 the patient presented with paraparesis and paresis of right arm which did not respond to corticotherapy. A spinal RMI revealed in the cervical spinal an intra spinal cord tumour, further diagnosed as ependymoma, and a parietal region meningioma. We call attention to this rare association of central nervous system tumour and MS, enphasizing the need for investigation of new and uncommon symptoms during the evolution of MS.  相似文献   
49.
PURPOSE: Prognosis of patients with glioblastoma is poor. Therefore, in glioblastoma patients, we analyzed whether antitumor vaccination with a virus-modified autologous tumor cell vaccine is feasible and safe. Also, we determined the influence on progression-free survival and overall survival and on vaccination-induced antitumor reactivity. PATIENTS AND METHODS: In a nonrandomized study, 23 patients were vaccinated and compared with nonvaccinated controls (n = 87). Vaccine was prepared from patient's tumor cell cultures by infection of the cells with Newcastle Disease Virus, followed by gamma-irradiation, and applied up to eight times. Antitumor immune reactivity was determined in skin, blood, and relapsed tumor by delayed-type hypersensitivity skin reaction, ELISPOT assay, and immunohistochemistry, respectively. RESULTS: Establishment of tumor cell cultures was successful in approximately 90% of patients. After vaccination, we observed no severe side effects. The median progression-free survival of vaccinated patients was 40 weeks (v 26 weeks in controls; log-rank test, P = .024), and the median overall survival of vaccinated patients was 100 weeks (v 49 weeks in controls; log-rank test, P < .001). Forty-five percent of the controls survived 1 year, 11% survived 2 years, and there were no long-term survivors (> or = 3 years). Ninety-one percent of vaccinated patients survived 1 year, 39% survived 2 years, and 4% were long-term survivors. In the vaccinated group, immune monitoring revealed significant increases of delayed-type hypersensitivity reactivity, numbers of tumor-reactive memory T cells, and numbers of CD8(+) tumor-infiltrating T-lymphocytes in secondary tumors. CONCLUSION: Postoperative vaccination with virus-modified autologous tumor cells seems to be feasible and safe and to improve the prognosis of patients with glioblastomas. This could be substantiated by the observed antitumor immune response.  相似文献   
50.
The International Prognostic Scoring System (IPSS) for myelodysplastic syndrome (MDS) is based upon weighted data on bone marrow (BM) blast percentage, cytopenia, and cytogenetics, separating patients into four prognostic groups. We analyzed the value of the IPSS in 142 children with de novo MDS and 166 children with juvenile myelomonocytic leukemia (JMML) enrolled in retro- and prospective studies of the European Working Group on childhood MDS (EWOG-MDS). Survivals in MDS and JMML were analyzed separately. Among the criteria considered by the IPSS score, only BM blasts <5% and platelets >100 x 10(9)/l were significantly associated with a superior survival in MDS. In JMML, better survival was associated with platelets >40 x 10(9)/l, but not with any other IPSS factors including cytogenetics. In conclusion, the IPSS is of limited value in both pediatric MDS and JMML. The results reflect the differences between myelodysplastic and myeloproliferative diseases in children and adults.  相似文献   
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