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41.
Hiroshi Ishikura 《Pathology international》1990,40(11):815-819
Intracytoplasmic lumina, each with a peripheral halo and spikes, a hitherto undescribed histological structure, were found in several human carcinomas. Similar structures found at the free surfaces of carcinoma cells, or those composed of several individual carcinoma cells, were designated extracytoplasmic lumina with a peripheral halo and spikes. Haloes were seen along the cytoplasm around the lumina, and the spikes penetrated into the cytoplasmic haloes. Transmission electron microscopy revealed that these spicular bodies were lumina equipped with microvilli containing an actin core. Spicular bodies were found in the following neoplasms; 22% of hepatocellular carcinomas (11/50), 35% of colonic adenocarcinomas (7/20), 31% of gastric adenocarcinomas (16/51). In contrast, no or only very occasional spicular bodies were found in thyroid (0/20) and mammary (1/22) adenocarcinomas. Although the diagnostic value of this structure is unknown at the present time, its identification in a carcinoma may be a histologic indicator of its endodermal nature. Acta Pathol Jpn 40: 815-819, 1990. 相似文献
42.
目的 观察应用引导管芯做引导,更换经口气管内导管的临床效果。方法 随机选择26例已完成气管内插管的病人,将引导管芯插入气管导管内至隆突水平,并拔出气管导管;将欲更换的气管导管套在引导管芯外,在管芯引导下将气管导管插入气管内,完成换置;结果 全部病例均顺利完成更换导管,换管过程中病人氧合良好,术后未发生与更换导管相关并发症;结论 应用引导管芯更换气管内导管,方法安全,简便易行,可替代传统换管方法。 相似文献
43.
The lingual papillae and their connective tissue cores (CTC) from Reeves’ muntjac deers (herbivorous artiodactyla) were studied using light and scanning electron microscopy and then compared to those of other mammalian species. At the posterior portion of the tongue, the Reeves’ muntjac has a lingual prominence on which large conical papillae are distributed. On the dorsal surface of the anterior tongue, numerous filiform papillae were found. Externally, each filiform papilla consists of a rod-shaped main process and several small accessory processes. Their CTCs consist of 10 or more rod-shaped processes arranged in a horseshoe pattern and several posterior processes forming a small circular pattern. This structure is a common characteristic of artiodactyla, through which Reeves’ muntjac deer can be categorized in a position in the artiodactyla class lying between the bighorn sheep and the East African bongo. Fungiform papillae are distributed among the filiform papillae on the anterior portion of the tongue. Large fungiform papillae are also sparsely distributed on the lingual prominence and have several taste buds in the epithelium on the surface. Ten or more vallate papillae are distributed at the postero-lateral area of the lingual prominence and numerous taste buds are distributed in the epithelium of their side. 相似文献
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关于我院图书馆中外文期刊利用状况的调研 总被引:2,自引:0,他引:2
目的 :明确图书馆专业期刊资源对科研活动的文献保障状况 ,初步制订出我馆的专业核心期刊表 ,以形成特色馆藏。方法 :应用流通统计法确定本馆的期刊文献利用情况 ,在此基础上 ,采用引文分析法确定我馆的核心期刊。结果 :本院研究生和教研人员引用文献的来源主要集中在 188种外文期刊和 69种中文期刊中 ,故这 188种外文期刊和 69种中文期刊可初步定为我馆的核心期刊。结论 :调研结果可作为图书馆确定藏书建设方向和特色的依据。 相似文献
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47.
本文ELLSA检测,对55例HBV感染者血清中的抗-HBcIgM随访研究其动态变化。结果发现,急性乙肝35例抗-HBcIgM的阳性率在入院时,6个月,12个月分别为100%(35/35),86%(31/36),及34%(6/18),提示抗-HBcIgM在6个月大都保持阳性,至12个月大部分消失;“无症状”携带者20例抗-HBcIgM阳性率在首检时,6个月,24个月都为100%(各为20/20,17/17,及10/10),提示“无症状”携带者的抗-HBcIgM很难自然消失,同时把抗-HBcIgM和HBsAg检测对比,提示HBsAg阴性不能排除急性乙肝的诊断。 相似文献
48.
目的:研究铁路驾乘作业对铁路机车司机神经行为功能的影响情况。方法:采用随机整群抽样法,抽取机车司机238名,另选年龄、工龄等条件类同的车站工作人员190名,按照WHO神经行为核心组合测试并分析比较行为功能。结果:与对照组相比,机车司机的反映情感状态的6项指标均受到显著或非常显著的不利影响。神经反应速度也受到了一定影响,表现在简单反应时中的最快及平均反应时间延长。另外,反映手的操作速度以及眼手协调功能的指标利手与非利手操作速度也较对照组明显下降,进一步分析可见,随着工龄或年龄的延长,上述指标受影响的程度呈逐渐增加的趋势。结论:神经行为核心测试组合在检测机车司机的亚临床职业损害方面是一项灵敏的指标 相似文献
49.
When first introduced, the advanced breast biopsy instrumentation (ABBI® ) system seemed to have many advantages as a diagnostic procedure. Problems have arisen, however, both in terms of patient unsuitability and mechanical failure. In addition, there has been uncertainty as to whether the complete lesion removal it afforded could be considered definitive treatment in malignant cases. Incision margins were looked at to investigate that possibility. Of the 183 patients we saw in our first year of experience with ABBI, 48 (26%) were rejected for being poor candidates for it. In the remaining 132 biopsies there were 31 (23%) technical difficulties. All told, 14 malignancies were discovered, all of which appeared to have pathology-free incision margins radiologically. However, 13 of these 14 (93%) proved on pathologic examination to have residual malignancy. ▪ 相似文献
50.
The reversal learning capacity of young rhesus monkeys in visual discrimination tasks was examined during daily exposure to dietary lead acetate throughout the first year of life. While not affected in physical development, all lead-treated monkeys showed performance deficits on reversal learning tasks. These deficits were independent of lead-induced changes in motivation. Over a series of problems, the overall learning rate of monkeys with blood lead concentrations in the range of 70-90 microgram/dl was retarded, which resulted partly from a pronounced difficulty in attaining criterion on the first of a series of reversals within a given problem. This latter deficit resulted from an increase in errors, balks, and total trials to criterion on the first reversal. Monkeys exposed to blood lead concentrations of 40-60 microgram/dl required significantly more trials to finish all problems, but did not show the first-reversal deficit. Theoretical implications of these data were discussed. 相似文献