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Marija Damjanovska Erika Cvetko Maxine M. Kuroda Alenka Seliskar Tanja Plavec Katarina Mis Matej Podbregar Tatjana Stopar Pintaric 《Veterinary anaesthesia and analgesia》2019,46(2):236-245
Objective
To test whether neurotoxic effects of a bupivacaine liposome injectable suspension differ from those of a standard formulation of bupivacaine hydrochloride (HCl) after intraneural injection into the sciatic nerves in pigs.Study design
Prospective, randomized study.Animals
Fifteen pigs, hybrids of Landrace and Large White.Methods
After the National Ethics Committee approval, 15 pigs were randomly allocated to three groups (n = 5/group) to receive intraneural injections of 4 mL of 1.33% bupivacaine liposome injectable suspension, 0.5% bupivacaine HCl or normal saline. Serial neurologic examinations were conducted to detect sensory and motor response to noxious stimuli using a modified Thalhammer’s scale at 2 hour intervals for the first 12 hours after injection and daily thereafter for 2 weeks. Fiber characteristics (density) of the harvested sciatic nerves were measured during histomorphometric analysis. Inflammatory response was studied using immunohistochemical analysis. Data were tested using analyses of variance; p values for paired comparisons were Bonferroni adjusted.Results
Compared with bupivacaine HCl, bupivacaine liposome injectable suspension provided longer sensory (11.2 ± 1.8 hours versus 3.2 ± 1.1 hours, respectively, p < 0.0001) and motor (10.0 ± 2.0 hours versus 4.0 ± 1.4 hours respectively, p < 0.0001) blockade. Histomorphometric parameters were similar among the groups. No changes in axonal density or myelin structure indicative of injury to the sciatic nerves were observed in any of the groups. Number of immunopositive cells did not differ between the bupivacaine liposome injectable suspension (23 ± 6 cells per mm2) and the bupivacaine HCl groups (21 ± 4 cells per mm2), p > 0.90.Conclusions and clinical relevance
Intraneural injections of bupivacaine liposome injectable suspension or bupivacaine HCl in our porcine model did not result in evidence of neurotoxicity. 相似文献13.
Two sizes of excised microcosms (15 and 30 cm in diameter) and 30 cm diameter homogenized microcosms were compared with field plots to assess the transport of As in a grassland ecosystem. The purpose of the experiment was to determine the suitability of using microcosms for measuring the transport of toxic substances through grassland ecosystem components (soil, grass, and soil water). Arsenic was applied to each set of microcosms and the field plots, at rates of 0, 0.5, and 5.0 mg cm?2. Results show that As was highly assimilated by grass, with the greatest concentration being 720 ppm. The microcosms were found to represent the field plots in terms of As transport, and offer several advantages over field testing of toxic substances. 相似文献
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Paradis Sylvain Wheatley Brian Boswell-Purdy Jane Bélisle Denis Cole Maxine Lickers Henry Hayton Alan Davies Kate 《Water, air, and soil pollution》1997,97(1-2):147-158
The relationship between the consumption offish containing methylmercury (MeHg) and human MeHg levels has been studied for many years. Although this relationship has been demonstrated and some models have been developed to assess the risks associated with fish consumption, there is still a need for a simple and efficient predicting tool that can be applied to community settings. This paper provides such a practical model developed through empirical evidence using two sources of data. In ideal conditions, models used to identify hazardous behaviour in individuals would be derived from theoretical and clinical models, however, these conditions are often technically difficult to meet. To overcome this problem, a more empirically oriented model has been developed, based on the estimation of personal mercury intake and its comparison to the Tolerable Daily Intake. The theory and methodology of the model development, including technical limitations, are presented first. The methodology is then applied to the real data to create the final model and the results given. Finally, a discussion of the model's accuracy, limitations and usefulness as a community health assessment tool is presented. 相似文献
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Jain M Arvanitis C Chu K Dewey W Leonhardt E Trinh M Sundberg CD Bishop JM Felsher DW 《Science (New York, N.Y.)》2002,297(5578):102-104
Pharmacological inactivation of oncogenes is being investigated as a possible therapeutic strategy for cancer. One potential drawback is that cessation of such therapy may allow reactivation of the oncogene and tumor regrowth. We used a conditional transgenic mouse model for MYC-induced tumorigenesis to demonstrate that brief inactivation of MYC results in the sustained regression of tumors and the differentiation of osteogenic sarcoma cells into mature osteocytes. Subsequent reactivation of MYC did not restore the cells' malignant properties but instead induced apoptosis. Thus, brief MYC inactivation appears to cause epigenetic changes in tumor cells that render them insensitive to MYC-induced tumorigenesis. These results raise the possibility that transient inactivation of MYC may be an effective therapy for certain cancers. 相似文献
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