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11.
S Haga K Shigesada Y Namba H Tanaka S Imai J Morimoto S Hiroishi H Yamamoto N H Sarkar J Hilgers 《Cancer letters》1992,65(3):201-207
Monoclonal and polyclonal antibodies specific to an open reading frame of the mouse mammary tumor virus long terminal repeat were generated using an open reading frame-beta-galactosidase fusion protein produced in E. coli. Both antibodies reacted with the open reading frame-beta-galactosidase fusion protein but not with beta-galactosidase alone using an immunoblotting technique. It is concluded that these antibodies were specific for the protein encoded by the open reading frame of the mouse mammary tumor virus long terminal repeat. 相似文献
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C Sekar S Rajasekaran Rajesh Kannan Shashidhar Reddy T Ajoy Prasad Shetty Yogesh K Pithwa 《The spine journal》2004,4(3):261-264
BACKGROUND CONTEXT: Administration of analgesic medication, before the actual onset of painful stimulus, is more effective than that after the onset of painful stimulus. This is the principle of preemptive analgesia. Although it is often considered superior to other forms of analgesia, its role in postoperative pain relief after lumbosacral spinal surgery has not been fully investigated. PURPOSE: To analyze the efficacy of preemptive analgesia with a single caudal epidural injection for patients undergoing surgeries on the lumbosacral spine by the posterior approach. STUDY DESIGN/SETTING: Randomized, double-blinded and controlled clinical trial. PATIENT SAMPLE: Eighty-two patients who underwent discectomy in the lumbosacral spine by the posterior approach, with or without instrumentation, were randomized to the control group (n=40) and to the study group (n=42). METHODS: Patients in control group received a single caudal epidural injection of 20 ml of normal saline. Patients in study group received a single caudal epidural injection of 20 ml containing bupivacaine and tramadol as the active agents. The time interval between this injection and the surgical incision was never less than 20 minutes in either of the groups. This facilitated enough time for the drug to get fixed to the nerve roots, leading to effective preemptive analgesia. OUTCOME MEASURES: Patients were monitored for postoperative pain immediately after surgery when they had completely recovered and regained consciousness from general anesthesia, and subsequently 4, 8, 12 and 24 hours thereafter. Pain was quantified using the visual analog scale (VAS) and the verbal rating scale (VRS). The time at which supplemental analgesic medication was first demanded in the postoperative period by the patient was also noted. RESULTS: The two groups were comparable for age, sex, body weight and the type of surgery they underwent. Because the data did not have a normal Gaussian distribution, the one-tailed Mann-Whitney test, being a nonparametric test, was adopted for statistical analysis. Accordingly, VAS and VRS values at all time intervals were significantly lower (p<.0001) in the study group as compared with the control group. This indicated significantly better pain relief in the study group. There was also a significant delay (p=.0041) in the first demand for supplemental analgesic medication in the postoperative period in the study group. No complication specific to the procedure was noted except for the development of postoperative urinary retention, which was transient and appropriately managed with urinary catheterization. CONCLUSIONS: Preemptive analgesia with a single caudal epidural injection of bupivacaine and tramadol is a safe, simple and effective method for postoperative pain relief. 相似文献
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Summary Ultrastructural and tracer studies have demonstrated that vasogenic edema, a serious complication of brain tumor is the result of increased permeability of tumor vessels. However, not much information is available on the alterations in the vessels in the peritumoral areas. Therefore, we studied the ultrastructural changes in the tumor micro-blood vessels (MBVs) in 20 cases of glioma and compared these with the changes in the peritumoral MBVs in 10 of these cases.The tumor MBVs showed remarkable structural changes, viz, increase in pinocytotic vesicles, large vacuoles and microvilli in the endothelial cells, varying degrees of endothelial attenuation and fenestration, an occasional partially or completely opened-up junction and some pale and edematous endothelial cells, which can adequately explain their increased permeability.The peritumoral MBVs also showed evidence of increased permeability in the form of increased pinocytotic vesicles, large vacuoles and microvilli associated with pale and edematous cytoplasm of some endothelial cells. Thickened multilayered basement membrane, absence of ensheathment of capillary basement membrane by astrocytic cell processes and widened perivascular space were observed in both tumoral and peritumoral MBVs.An interesting observation was that in the peritumoral MBVs, the pinocytotic vesicles were most conspicuously seen on the abluminal side of the endothelial cells often fused with the abluminal plasma membrane. Although a static study like this cannot indicate any definite direction of movement of fluid, we feel that the occurrence of reverse pinocytosis is a distinct possibility in the peritumoral MBVs and that it may be an important means of resorption of edema fluid. 相似文献
15.
Gallium and thallium radionuclides have both diagnostic and therapeutic applications in the field of nuclear medicine. Poly(N-vinylpyrrolidone) (PVP) is routinely used as a drug base because of its excellent biocompatibility. In this paper, complex formation abilities between no-carrier-added (66,)(67)Ga/(199)Tl radionuclides and PVP have been studied. It has been found that aqueous 5% PVP solution can almost quantitatively back extract (66,)(67)Ga/(199)Tl radionuclides from an organic phase, which proves the complexing ability of PVP with (66,)(67)Ga/(199)Tl. Tl(3+) is more efficient to form Tl-PVP complexes than Tl(+). However, Tl(3+)-PVP complexes are less stable than Ga(3+)-PVP complexes. 相似文献
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M. R. Sarkar B. A. Rahn U. Pfister H. U. Keller S. M. Perren 《Archives of orthopaedic and trauma surgery》1990,109(2):97-101
Summary Temporary impairment of blood supply has been suggested to cause bone remodeling. The degradation of cells and matrix and the attraction of resorbing cells were examined in this study. Bone specimens of rabbits were stored in vitro for 2–20 days. At the end of this aging process the probes were tested for their chemotactic activity toward autologous leukocytes in a diffusion chamber. Both supernatant from the aged bone specimens and ground bone particles exhibited significant chemotactic activity that was specifically attracting monocytes. It is suggested that soluble bone matrix proteins or degeneration products liberated during ischemic damage to cortical bone initiate the resorptive process.This work was supported by the Swiss National Science Foundation, grant no. 3.857.0.83, and by the Studienstiftung des deutschen Volkes 相似文献
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