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991.
Hiroko Ida-Yonemochi Wael Swelam Chikara Saito Takashi Saku 《Journal of oral pathology & medicine》2005,34(1):59-61
A case of angiolipoma occurring in the buccal mucosa of a 69-year-old male is described. The patient had noticed a painless mass in his buccal mucosa for 2 years. The surgically removed tumor, measuring 9 mm in diameter, was mainly located in the submucosal layer with focal expansion into the muscle layer. Histologically, the tumor was well-demarcated and composed of proliferations of mature fat cells and fibrous connective tissue containing many small blood vessels, which were evenly distributed. There was diffuse infiltration of a large number of mast cells, which were immunopositive for vascular endothelial growth factor (VEGF) especially around blood vessels, suggesting that VEGF produced by mast cells in angiolipomas plays an important role in the vascular proliferation in this particular tumor. 相似文献
992.
A. Beamonte F. Goldfain-Blanc N. Casadevall D. Bazot H. Bertheux N. Claude 《Comparative clinical pathology》2005,14(1):61-65
As part of the early preclinical development of a new antipsychotic compound, Wistar rats of both sexes were dosed orally for upto 7 days. At high doses, expected changes in appearance and behavior, decreases in bodyweight gain and feed intake but also a fluid and pale bone marrow (BM) were observed. Blood cell counts were normal as were clinical chemical values. BM sections showed a red cell hypoplasia. Circulating reticulocytes and erythroblasts on BM smears were decreased suggesting that the compound might have a selective toxicity for the erythroid lineage. In a mechanistic experiment, rats were dosed for 9 days and phlebotomized after 7 days of exposure to stimulate erythroid regeneration. Red-blood cell mass, reticulocytes and erythropoietin (EPO) levels were monitored before and upto 48 h after bleeding. Results showed that an EPO-mediated pathogenesis could be excluded. The effect of the drug on the formation of Colony-forming units (CFU)-E and CFU-GM was then quantitatively measured in vitro after direct exposure to the compound. In two successive assays, rat or human BM cells were incubated with the drug dissolved in the collection medium at final concentrations of 0.3×10–7 –3×10–5 M. In the presence of adequate growth factors, CFU-E and CFU-GM were cultured and cell proliferation was compared between treated and control groups. Our results showed an expected inhibition by the drug of the growth of erythroid progenitors associated to a similar effect on myeloid progenitors. The CFU-E and CFU-GM of both human and rat sources were totally inhibited from the concentration of 3×10–5 M. The IC50 values were consistent with rat peak plasma levels reached in vivo by the drug. Therefore, the short-term cloning assays performed on rat BM cells were sensitive indicators of the hematotoxicity of the compound and were considered as predictive for human toxicity. 相似文献
993.
In primary visual cortex of hooded rats, pyramidal cells in layer V may be classified as long, medium, or short, on the basis of the layer in which the apical dendrite terminates. The present study determines which of these types of pyramidal cells project to the superior colliculus. Two different strategies were used to label corticotectal cells with horseradish peroxidase (HRP). In the first set of experiments, a large number of corticotectal cells were labeled by retrograde transport following injection of HRP into the superior colliculus. In the second set of experiments, single unit recording was used to identify corticotectal cells physiologically by antidromic activation from the superior colliculus. These cells were then impaled and labeled by intracellular iontophoresis of HRP. The results from both techniques suggest that only long pyramidal cells send an axon to the superior colliculus. These cells are distinguished by an apical dendrite that extends into layer I. We conclude that in hooded rats corticotectal cells in primary visual cortex are the long pyramids in layer V. 相似文献
994.
Summary This study was undertaken to elucidate, using the Golgi method, the neuropathological change in the brain of the macular mutant mouse, whose hemizygote (Ml/y) is considered to be a model of Menkes kinky hair disease (MKHD). The hemizygote mice gradually lost weight after 10 days of age and died with emaciation and seizure around day 15. The normal littermate (+/y) was well developed. In the cerebrum, the arborization of pyramidal neurons in the layer V of the Ml/y was the same as that in the +/y on day 10. However, development of arborization in the Ml/y was delayed in comparison with that in the +/y on days 12 and 14. Purkinje cells with several somal sprouts were observed in the cerebellum in both the Ml/y and +/y on day 7. The somal sprouts in the +/y had regressed gradually by day 12, while they were still in the anterior and middle lobes of the Ml/y on day 14. Additionally, the trunks of Ml/y stem dendrites became thicker and a cactus formation was recognized on the branching portion of the dendrites on day 14. Arborization of these abnormal Purkinje cells was distinctly poor compared with that in the +/y. These results suggest that the growth of the neurons is delayed in the Ml/y and simultaneously their cytoskeletal developments are disturbed, especially in the Purkinje cells. There is a close similarity in many respects to the neuropathological change in MKHD. 相似文献
995.
Judith D. Goldberg Arnold I. Weiss Kenneth J. Koury 《Journal of clinical periodontology》1986,13(5):411-414
In order to make effective use of the statistical theory of design of clinical trials for chronic diseases such as periodontal disease, certain issues must be considered. Any clinical trial requires that the disease definition be well-specified; that patient eligibility be explicit; that the observation times be explicit; that the duration and endpoint of therapy be specified; that the duration of subsequent followup observation be specified; and that the unit of observation (e.g., tooth, set of teeth, patient) be defined. In a chronic disease, the potential biases that can readily be introduced by self-selection of patients who enter the trial and/or who return for subsequent observation become more important, because subjects are required to remain on treatment and/or observation for prolonged periods. Further, the cyclical nature of some chronic diseases may require special attention to baseline definitions of active disease and disease outcome. These issues are illustrated with examples from clinical trials of hypertension, breast cancer screening, and Polycythemia Vera. Implications for periodontal disease are discussed. 相似文献
996.
997.
为运用循证医学方法对中药熏洗治疗膝骨性关节炎(OA)的临床疗效及安全性进行系统评价和Meta分析。全面收集了中药熏洗治疗OA的文献资料。在严格质量评价基础上,对研究结果进行定性分析。合并各篇优、良为阳性结果,中、差为阴性结果。利用RevMan4.1软件对多个研究结果的总体疗效进行固定效应模型的Meta分析,并进行敏感性分析。用漏斗图表示发表性偏倚。结果显示,中药熏洗治疗OA的效应值OR=2.68.95%可信区间为[1.82,3.95];敏感性分析显示效应值稳定;漏斗图图形不对称;无中药熏洗不良反应的报道。表明中药熏洗治疗OA有一定的疗效,由于漏斗图提示存在发表性偏倚,加上现有临床研究存在的方法学问题,现在的研究结论有一定的局限性,欲得出公认的结论,尚有待进行设计严谨的多中心、随机对照试验。 相似文献
998.
999.
1000.
靶向持续性组织间化疗治疗舌鳞癌的初步观察 总被引:3,自引:2,他引:1
目的观察靶向持续性组织间化疗治疗舌癌的疗效及安全性。方法将顺铂(缓释型)植入于10例舌癌患者癌区周围及中央,观察局部变化、全身反应与术后标本的病理结果。结果所有患者原发灶都有不同程度的缩小,部分缓解8例,无效2例(缩小约30%左右),有效率为80%。所有患者术后标本肉眼见肿块边缘药物所在区形成比较明显的纤维组织样反应;镜下见癌中央组织凝固性坏死,植入药物周围组织变性、坏死,转移淋巴结内可见部分坏死灶、组织变性。结论顺铂(缓释型)治疗舌鳞癌,疗效较好,操作简单,安全性高,毒副作用少,对转移淋巴结有一定的治疗作用。 相似文献