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41.
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N‐acyl‐dopamines are a novel class of biologically active lipids that have recently been identified in the brain and have the potential to interact with neural signaling pathways. This study seeks to determine the ability of N‐oleoyl‐dopamine, a synthetic amide of oleic acid and dopamine, to cross the blood brain barrier. We determined the tissue content of radioactivity in selected brain regions, in a short‐run study design, following injections of [3H]N‐oleoyl‐dopamine (0.4 µCi) into the internal carotid artery in the rat. These results were compared with intracarotid injections of [3H]dopamine and with intravenous injections of both radiolabeled compounds. The level of radioactivity was determined using liquid scintillation and was expressed as the percentage of its total dose injected per gram of tissue. We found that the 15‐min brain uptake of radioactivity, with no distinct regional variations, amounted to about 6% following the intracarotid [3H]N‐oleoyl‐dopamine, which was a significant 3–4‐fold increase over that following similar administration of [3H]dopamine. Intravenous injections of [3H]N‐oleoyl‐dopamine gave a much smaller yield of radioactivity in brain tissue samples which was still severalfold greater than that for intravenous [3H]dopamine. Qualitative thin‐layered chromatography screening showed the presence of unchanged N‐oleoyl‐dopamine in the brain following injections. We conclude that N‐oleoyl‐dopamine has an appreciable ability to cross the blood‐brain barrier, which contrasts the limited transfer of dopamine alone. N‐oleoyl‐dopamine might exert physiological effects due to its known affinity for the central vanilloid receptors or to better satisfying the brain tissue demand for dopamine. The study suggests a potential pharmacological role for N‐oleoyl‐dopamine delivered exogenously in helping regulate the brain function. Drug Dev. Res. 60:217–224, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   
43.
Treatment of rats with histamine releaser compound 48/80 caused changes in blood leukocyte populations. An increased number of PMN-leukocytes was observed. Tritoqualine only modestly reduced the number of granulocytes. In animals treated with compound 48/80 an activation of PMN-leukocyte latent collagenase of up to 80% was observed. This activation was partially inhibited (about 40%) in animals pretreated with tritoqualine. The results presented suggest that the beneficial effect of tritoqualine in allergic diseases may be in part connected with an indirect inhibition of collagenase activity.  相似文献   
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45.
Colorectal surgery is still associated with a significant morbidity and mortality rate, mostly related to suture failure. We have carried out a randomized experimental study in dogs on colonic anastomoses exposed to a number of anastomotic risk situations. A total of 42 dogs was used. They were divided into three study groups (control, occlusion and diverticulitis), with and without an endoluminal tube. The aim was to assess the efficacy of the endoluminal prosthesis using clinical and radiological assessment of anastomotic healing. Pre- and post-anastomotic intraluminal pressures were also measured to determine whether these might be a factor in suture failure. There were significant differences in suture failure in animals in which the endoluminal tube was used. Mean duration of placement was 10.5 days. In the colon healing study, no significant differences were found between the groups in the pathological examination or in the assay of hydroxyproline content. The presence of the endoluminal tube may increase the maximum pressure applied on the colon wall. No significant differences were found in the intracolonic pressure differentials between the different groups or after the inclusion of the endoluminal prosthesis. The results obtained establish the efficacy of the endoluminal prosthesis in protecting the colonic anastomosis, and could be a valuable technique in colonic anastomoses with a high risk of suture dehiscence.  相似文献   
46.
On the basis of analysis of 128 cases of serological incompatibility it was found that antibodies to Rh in titres of 1/8 or less constituted a good prognostic factor, and without evidence of fetal distress in USG examination this was not an indication to treatment undertaking. If the titre is from 1/16 to 1/128 the prognosis is worse and the degree of fetal haemolytic disease risk may be estimated on the basis of USG and Liley's zone. The prognosis is very bad in case of titre exceeding 1/128 and high Liley's zone, and without effective treatment of haemolytic disease in fetal life only few fetuses survive.  相似文献   
47.
The results of treatment of 17 patients--8 cases of leg bones defect due to osteitis and 9 cases of leg pseudoarthrosis has been presented. The osteosynthesis of the fragments was done with the use of Zespol fixator. In 14 patients the lesion has healed and satisfactory function of the extremity was restored.  相似文献   
48.
Retinal detachment in an aphakic eye is a grave therapeutical problem. There exists some fears that cataract extraction with implantation of an artificial lens may increase the number of these complications. Three hundred and seventy cases of cataract extraction with implantation of an artificial lens performed in our department were analysed from the point of view of the incidence of retinal detachment. The cataract was extracted extra- and intracapsularly and the artificial lens was implanted in the anterior as well as in the posterior chamber. During the period of observation--4 months to 3 years--it was established that the number of the retinal detachment in pseudophakia was not larger than in aphakic eyes without implant.  相似文献   
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50.
The purpose of the study was to assess hip joint development after the treatment of DDH with overhead traction and closed reduction complicated by growth disturbances of the proximal femoral epiphysis. Comparison was also made between joints affected by AVN and other treated joints. Antero-posterior radiographs of 107 hip joints (81 children) done during treatment and follow-up were retrospectively reviewed. The average age was 14.2 months (from 5 to 33 months) and age at the final follow up 20.7 years (minimum 14 years). AVN was detected in 31 (29%) of the hip joints. Type II necrosis according to Bucholz and Ogden classification system was the most common one. In the hips affected by growth disturbances of proximal femoral epiphysis there were worse final clinical and radiological results, osteoarthrosis and elongation of acetabulum were more often seen in comparison to other treated joints. There was no difference in terms of other parameters describing acetabulum. In 19 out of 31 cases deformity of femoral head was noted. AVN may present as a wide spectrum of pathology from mild, probably not significant growth disturbances of physis to severe deformity and lateralisation of femoral head. Statistically hips with AVN had worse final results and in cases with good congruity prognosis is often uncertain due to aspherical femoral head and secondary osteoarthrosis. Acetabular development is most often unaffected by AVN.  相似文献   
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