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The aim of the present study was to investigate if distant effects could be detected within the central nervous system after impact of a high-energy missile in the left thigh of young pigs. Pressure transducers implanted in various parts of the body of the animal, including the brain, recorded a short-lasting burst of oscillating pressure waves with high frequencies and large amplitudes, traversing the body tissue with a velocity of about that of sound in water (1,460 m/s). The distance between the point of impact and the brain and cervical spinal cord is in the range of 0.5 m. Macroscopic examination revealed that there was no gross brain tissue disruption or visible blood-brain barrier dysfunction. Light microscopic examination demonstrated myelin invaginations in the largest axons and shrinkage of axoplasm. Electron microscopic examination revealed a reduction in the number of microtubules, especially in the larger axons in the brainstem. Disintegration of Nissl substance, i.e., chromatolysis, was noticed after 48 hr in many Purkinje nerve cells in the cerebellum, concomitantly with the appearance of an increased frequency of association between lamellar bodies and mitochondria. Changes could also be observed in the cervical spinal cord and, at reduced frequency and extent, in the optic nerve and in other parts of the brain. These effects were evident within a few minutes after the trauma and persisted even 48 hr after the extremity injury. It is concluded that distant effects, likely to be caused by the oscillating high-frequency pressure waves, appear in the central nervous system after a high-energy missile extremity impact. 相似文献
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Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:9,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
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P S Eriksson B Carlsson O G Isaksson E Hansson L R?nnb?ck 《Brain research. Molecular brain research》1992,16(3-4):345-352
Primary astroglial cultures were incubated with delta (10(-6) M DPDPE) or kappa (10(-5) M U-50,488H) receptor agonists for 5 days. Thereafter, the acute inhibitory actions of delta or kappa receptor agonists on forskolin stimulated cAMP accumulation were assayed. The G alpha s, G alpha i-1 and G alpha i-2 mRNA levels were quantified after 5 days of either delta or kappa receptor agonist treatment using a solution hybridization, RNase protection assay. Pronounced effects were observed after 5 days of kappa receptor agonist [10(-5) M U-50,488H] incubation. This treatment resulted in an attenuation in the acute inhibitory action of delta and kappa receptor agonists. Furthermore, a decreased stimulatory action of forskolin was seen. Similar effects were also seen after delta receptor stimulation. We also investigated the effects after 24 h and 3 days of incubation with the kappa receptor agonist (10(-5) M) U-50,488H. The 24 h incubation resulted in a decreased sensitivity to the acute inhibitory action of delta and kappa receptor agonists in the astroglial cultures. This effect was further accentuated after the 3 days of incubation with 10(-5) M U-50,488H. No significant change was seen in the basal accumulation of cAMP after incubation with the kappa agonist U-50,488H. However, after 5 days of incubation with the delta agonist DPDPE, a significantly increased basal accumulation of cAMP was seen in the astroglial cultures. After 5 days of delta or kappa agonist incubation, an increase in G alpha s mRNA level and a decrease in G alpha i-2 mRNA level was seen compared with controls. No statistically significant alterations in the amount of G alpha i-1 mRNA were seen. The data obtained in the present study indicate that the effects of long-term opioid treatment alters the sensitivity of glial cell opioid receptors. Furthermore, long term opioid treatment induces alterations in glial G-protein mRNA levels. 相似文献