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排序方式: 共有8908条查询结果,搜索用时 31 毫秒
81.
目的:探讨细针吸取活检细胞学对乳腺癌的诊断价值。方法:以术后病理诊断为对照(134例),光镜下观察521例乳腺肿瘤的针吸涂片。结果:在54例乳腺癌中,细胞学诊断正确者49例(90.7%),可疑者4例(7.4%),假阴性者1例。同期细胞学诊断为乳腺癌者未见假阳性。结论:细针吸取活检对乳腺癌的定性和分级诊断均准确可靠。 相似文献
82.
The Value of Fine Needle Aspiration Cytology in Breast Fibromatosis: Study of Two New Cases and Review of the Literature 总被引:1,自引:0,他引:1
▪ Abstract: We report two new cases of breast fibromatosis studied by needle aspiration cytology observed in a 32-year-old man and a 49-year-old woman. The lesions manifested as palpable, painless, and firm masses of the para-areolar breast soft tissues. Preoperative fine needle cytology revealed scant cellularity, featuring oval and spindle cells with bland nuclei and occasional larger polygonal cells with high nuclear:cytoplasmic ratio. Histologically, interwoven fascicles of spindle cells with bland nuclei, infiltrating the adjacent breast fat, were recognized. Based on available reports in the literature, we concluded that needle aspiration cytology, although not entirely specific, may be a source of important information in patients with breast fibromatosis. In particular, it confidently allows the exclusion of breast cancer and other more common diseases and is useful in planning a surgical approach to the lesion. ▪ 相似文献
83.
N. Carlon A. Navarro C. Giorgetti R. Roulier 《Journal of assisted reproduction and genetics》1992,9(5):475-481
Failure of in vitro fertilization or very low cleavage rates may occur even though oocyte and semen parameters seem satisfactory. Quantified ultrastructural study of spermatozoa was performed in such cases of failure (n =6) or low cleavage rate (<20%; n =4). Through 1 to 11 retrievals, the number of inseminated oocytes ranged from 14 to 145. The results were compared to those of six fertile men. Quantification was achieved by cataloguing cell defects of the spermatozoon heads and mid-/principal pieces of the flagella. Using the data from each specimen, the percentages of total cellular abnormalities in the head/mid-/principal pieces were established. At the level of the head overall percentages for six groups of defects were determined. The overall percentage of combined head abnormalities, defined as the presence of at least three of these six defects on the same spermatozoon head, was established. Statistical differences among control and patient groups were analyzed by nonparametric Mann—Whitney Utest. The percentages of anomalies of the midpiece and of the principal piece were not significantly different between patients and controls. Motility assessed by spermogram was considered functionally uncompromised. In eight patients the percentage of cell alterations of the head (93–100 vs 77.3 ± 6.4%) and the percentage of combined anomalies of the head (78.1–100 vs 60.8 ± 8.5%) were significantly different between patients and controls. In two cases, the percentages established for all head parameters considered were not globally different from those observed in controls. Thus in 8 cases of 10, electron microscopy with quantified analysis supplied valuable evidence about the poor quality of these sperm samples judged as normal under light microscopy and may provide an explanation for their impaired fertilizability. In the two other cases the fact that the sperm appeared to be ultrastructurally normal does not rule out functional sperm pathology. Alternatively, defects in the oocyte may also account for unexplained failures of in vitro fertilization. 相似文献
84.
骨立拮抗维甲酸所致大鼠骨质疏松的实验研究 总被引:2,自引:1,他引:2
目的 观察骨立对维甲酸所致骨质疏松大鼠的股骨骨密度、骨矿含量的影响。方法 采用ig维甲酸造成大鼠骨质疏松模型 ,使用骨立高、中、低 3种剂量分别进行治疗 ,观察其结果并与空白对照组和阳性对照药物组进行比较。结果 骨立 3个剂量治疗的骨质疏松大鼠的股骨骨密度和骨钙、骨磷含量均明显高于骨质疏松模型组大鼠 (P <0 .0 1或 0 .0 5 ) ,骨立高、中剂量组大鼠的尿钙排泄量明显低于骨质疏松模型组大鼠 (P <0 .0 1) ,其中以高剂量组疗效最佳。结论 骨立可明显提高骨质疏松大鼠的骨密度并升高其骨钙、骨磷的含量 ,降低尿钙排泄量 ,从而拮抗维甲酸所致的大鼠骨质疏松症。 相似文献
85.
86.
鲑降钙素吸入粉雾剂的制备及其药剂学性质研究鲑降钙素吸入粉雾剂的制备及其药剂学性质研究 总被引:3,自引:1,他引:3
目的喷雾干燥法制备鲑降钙素吸入粉雾剂,考察其主要药剂学特性。方法按中国药典2000年版方法测定鲑降钙素吸入粉雾剂排空率及有效部位沉积量,扫描电镜观察粉粒的形态,激光粒度测定仪测定粉粒的粒径大小及分布,差热分析及X射线粉末衍射考察吸入粉雾剂载体的晶型。结果有效部位鲑降钙素沉积量均在10%以上,排空率均在90%以上;相对湿度在52%以下,粉粒呈圆整的分散状态;当RH=75%时粉粒发生较多的粘连和聚集;粉体平均粒径为1.67 μm;差热分析结果显示:吸入粉雾剂中L-亮氨酸的熔融热较单一组分在喷雾干燥后显著下降;X射线粉末衍射图谱中,吸入粉雾剂载体的衍射峰强度较喷雾干燥前显著下降。结论在鲑降钙素吸入粉雾剂载体系统中加入甘露醇,粉粒圆整,加入L-亮氨酸可形成超低密度载体;扫描电镜的结果提示,应严格控制吸入粉雾剂贮存时环境的湿度;喷雾干燥复合载体更有助于无定形的形成。 相似文献
87.
88.
目的探讨乳腺癌针吸细胞学(FNAC)诊断准确性。方法分析1326例乳腺肿块针吸细胞学诊断,并与323例手术后病理组织学诊断结果对比。结果本组 FNAC 诊断敏感性为97.1%,特异性为97.3%,假阳性率为2.7%,假阴性率为2.9%,诊断符合为97.2%。结论乳腺肿块 FNAC 检查是一种实用价值很高的诊断方法。文中对影响 FNAC 诊断的因素进行了讨论。 相似文献
89.
90.
蒙脱石散对盐酸左氧氟沙星体外吸附的影响 总被引:7,自引:0,他引:7
目的: 探讨蒙脱石散对盐酸左氧氟沙星体外吸附的影响.方法: 采用不同剂量的盐酸左氧氟沙星分别与3 g蒙脱石散混合,加入0.1 mol·L-1盐酸溶液中,在(37±0.5)℃水浴中恒温2 h后过滤,用紫外分光光度法测定盐酸左氧氟沙星的含量变化.结果: 蒙脱石散对盐酸左氧氟沙星的吸附率为(98.37±0.03)%.结论: 蒙脱石散对盐酸左氧氟沙星有极强吸附,因此应避免两种药物同时服用. 相似文献