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31.
N. Dincer, S. Balci, A. Yazgan, G. Guney, R. Ersoy, B. Cakir and G. Guler
Follow‐up of atypia and follicular lesions of undetermined significance in thyroid fine needle aspiration cytology Objective: To report our experience of atypia of undetermined significance (AUS)/follicular lesion of undetermined significance (FLUS) rate and outcome. Methods: Among 7658 patients with 19 569 nodules, 524 (2.7%) nodules were diagnosed as AUS/FLUS on fine needle aspiration (FNA). After exclusion of patients with simultaneous nodules that were suspicious for follicular neoplasm or malignancy or that were malignant, 368 (4.8%) patients were diagnosed as AUS/FLUS. The outcome of 146 patients who had undergone surgery or repeated fine needle aspirate at the time of preparation of this study was evaluated. The original FNAs were matched to repeated FNAs and thyroidectomy or diagnostic lobectomy specimens. Results: Seventy‐two (19.6%) of the 368 patients had directly undergone surgery, either a lobectomy or a thyroidectomy: of these, 27 (37.5%) had neoplastic nodules (21 were malignant). Seventy‐four (20.1%) of the 368 patients had repeat FNA. On second FNA, 47 of 74 (63.5%) were benign, three were suspicious for follicular neoplasm, one was malignant and 23 (31.1%) were non‐diagnostic. Four patients had a third FNA: two were AUS/FLUS, one was malignant and one non‐diagnostic. One patient had a fourth FNA, which was diagnosed as AUS/FLUS. Sixteen (21.6%) of 74 patients with repeat FNA had surgery: three of these had neoplastic nodules (two were malignant). Overall, 88 of the 368 (23.9%) patients had a thyroidectomy of which 30 (34.1%) were neoplastic and 23 (26.1%) malignant. The neoplastic rate for patients who were once diagnosed with AUS/FLUS was 8.2% and the malignancy rate 6.3%. The malignancy rate for patients on follow‐up at the time we prepared the study was 15.7% (23/146); 222 remained on follow‐up without surgery or repeat FNA or were managed elsewhere. Conclusions: Although in this category repeat FNA is expected rather than excision, we suggest evaluation of all AUS/FLUS patients in multidisciplinary meetings to decide management and recommend follow‐up of all patients with this diagnosis.  相似文献   
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?. P. Marin?ek, N. Nolde, I. Kardum‐Skelin, R. Nizzoli, B. Önal, T. Rezanko, E. Tani, K. T. Ostovi?, P. Vielh, F. Schmitt and G. Kocjan
Multinational study of oestrogen and progesterone receptor immunocytochemistry on breast carcinoma fine needle aspirates Objectives: To collect data on the variability of immunocytochemical (ICC) procedures used to detect oestrogen/progesterone receptors (ER/PR) on cytological material; to test the reproducibility of results; and to identify the crucial points in the ICC procedures that affect the result. Methods: Ten laboratories from eight countries participated in a two‐part study. In the first part, one of the participants (the coordinator) prepared and distributed cytospins from a fine needle aspirate of a primary breast carcinoma. Laboratories performed ICC staining for ER/PR according to their own methods on the test slides and in‐house positive controls. Slides were returned to the coordinator together with information on the preparation of positive control slides and the ICC methodology used. In the second part, obligatory methods of fixation and antigen retrieval were specified. Evaluation of results included grading the number of positive cells, staining intensity, background staining, cytoplasmic staining, sample condition and cellularity. Participants evaluated their own results, which were subsequently evaluated by the coordinator. Results: There was great variability in the preparation of slides for in‐house controls and ICC methodology. The outcome of ICC staining of in‐house control slides was excellent in two laboratories, adequate in three, sub‐optimal in four and inadequate in one. Only six obtained a positive reaction on the test slides and not all were of a high quality. Results of the second run were greatly improved in terms of cellularity of in‐house positive control slides, and scores for the percentage of stained cells and staining intensity of control and test slides. Cytospins and monolayer (ThinPrep®) preparations were superior to direct smears; methods of fixation and antigen retrieval were the key points in the staining process. Conclusions: Our experience points to the need for guidelines for hormonal receptor determination and external quality control on cytological material, in order for cytological methods to be used in routine clinical practice with a suitable degree of confidence.  相似文献   
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【目的】明确小菜蛾Plutella xylostella成虫下唇须感器的形态结构及感器神经元的投射。【方法】利用光学显微镜观察和扫描电子显微镜观察下唇须结构和感器类型,利用神经回填技术和激光共聚焦显微镜观察下唇须感器神经元在脑部的投射。【结果】小菜蛾成虫下唇须共3节,其上存在Böhm氏鬃毛、钟形感器、鳞形感器、锥形感器、微毛形感器5种不同类型的感器和一个陷窝器结构。Böhm氏鬃毛短小尖细,钟形感器形如顶部凹陷的圆帽,两种感器均分布于下唇须第1节,且大小上均无雌雄二型差异;鳞形感器形同柳叶,锥形感器粗而直,均散生于下唇须的第2和3节,两种感器在大小上均存在雌雄二型差异,其中雌性的鳞形感器显著大于雄性的,根据其雌雄二型差异现象推测雌蛾的鳞形感器可能与感受寄主植物挥发物有关;下唇须第3节中上部具有一个圆形陷窝器结构,雄虫的陷窝器内径为5.68±0.33μm,雌虫的为6.03±0.23μm,雌雄间无显著性差异;凹坑内长有表面光滑的微毛形感器。小菜蛾下唇须感器神经元主要投射于脑部咽下神经节、每个触角叶的下唇须陷窝器神经纤维球和腹神经索3条通路。【结论】阐明了小菜蛾下唇须感器的类型、分布和形态特征及其感器神经元在脑部的投射形态,为深入了解小菜蛾下唇须感器的生理和功能奠定了基础。  相似文献   
37.
There are a huge number of phylogenetic studies based on mitochondrial DNA (mtDNA); however, these may represent gene trees that may not be congruent with the species tree. A solution to this problem is to include additional, independent, loci from the nuclear genome. At fine taxonomic levels, i.e. between populations and closely related species, previously suggested nuclear markers such as intron sequence data may not be appropriate. In this study we investigate the use of amplified fragment length polymorphisms (AFLP) to aid determination of the species tree for 24 specimens of a medically important snake, Trimeresurus albolabris. This is of particular importance for many venomous snakes as venom often varies intraspecifically. Five different primer combinations produced 434 bands and were analysed by constructing a phylogenetic tree using neighbour joining and principal component analysis. Results were similar across all methods and found distinct groupings. The results were compared with mtDNA data and a reconciled tree was constructed in order to determine the species tree for T. albolabris. We found that T. albolabris (sensu lato) is not monophyletic. Specimens from the Indonesian islands (except West Java) form a distinct clade and we propose elevation to species level. A specimen from Nepal is also distinct and suggests that this population also deserves specific status. We suggest that AFLPs may prove a valuable aid in determining species trees as opposed to gene trees at fine taxonomic levels and this should facilitate the incorporation of molecular data into such activities as antivenom production and conservation management.  相似文献   
38.
There is a great variability in the success of horse oocyte maturation and fertilization among laboratories. This study was conducted to determine if the meiotic and developmental competence of horse oocytes could be dependent on the method of oocyte collection, i.e., aspiration of follicular fluid with a vacuum apparatus, or opening follicles and scraping the granulosa layer. Horse oocytes were recovered from abattoir ovaries by aspiration or scraping and classified as having compact (Cp), expanded (Ex), or partial (P) cumuli. In Experiment 1 (Part A in May and Part B in October), oocytes were fixed immediately after collection to assess whether the collection method influenced the initial chromatin configuration of oocytes. In Experiment 2, in vitro maturation rates of oocytes recovered by aspiration or scraping were compared. In Experiment 3, oocytes were matured in vitro and submitted to intracytoplasmic sperm injection (ICSI). Initial chromatin configuration differed according to collection method in that there was a significantly higher prevalence of diffuse chromatin within the germinal vesicle in oocytes recovered by scraping than in oocytes recovered by aspiration (29/87, 33% and 28/166, 17%, respectively; P < 0.01). Maturation of oocytes to metaphase II did not significantly differ between scraped and aspirated oocytes (56/101, 55.4 % vs. 65/106, 61.4%, respectively). The overall pronucleus formation rate after ICSI of oocytes recovered by scraping was not significantly different than that of oocytes recovered by aspiration (50/99, 52.6% vs. 50/85, 68.5 %, respectively); however, the rate of abnormal fertilization was significantly higher for oocytes collected by aspiration (14/73, 19% vs. 6/94, 6%, respectively; P <0.05). These results demonstrate that the collection method affects the population of recovered oocytes and may contribute to differences in results observed among laboratories working with horse oocytes.  相似文献   
39.
Objectives: Recently, there has been a resurgence of interest in the interactions between oral conditions and a number of prevalent systemic diseases. The morbidity and mortality of the dependent elderly that result from aspiration pneumonia have been recognized as a major geriatric health problem. The purpose of this study was to gain more information on the microflora of plaque on dentures and to assess the existence of oral infectious pathogens potentially causing the respiratory disease in the dependent elderly. Subjects and Methods: The denture bacterial flora of 50 dependent elderly were examined to identify microorganisms by the culture method. Results: 18 species of microorganisms were detected in denture plaque in this study. A variety of pathogens with the potential to cause respiratory infection pathogens colonized on the dentures of dependent elderly. Conclusion: The results of the present study revealed that bacteria that commonly cause respiratory infection colonized on the dentures of dependent elderly, suggesting that denture plaque may function as a reservoir of potential respiratory pathogens to facilitate colonization on the oropharynx.  相似文献   
40.
H. Gerke, M. K. Rizk, A. D. Vanderheyden and C. S. Jensen
Randomized study comparing endoscopic ultrasound-guided Trucut biopsy and fine needle aspiration with high suction
Objectives:  Endoscopic ultrasound (EUS)-guided Trucut biopsy (TCB) enables acquisition of tissue cores for histological assessment. Because of the rigid needle and the spring mechanism, tissue acquisition can be difficult from regions that require sharp angulation of the echoendoscope. Fine needle aspiration with high suction (FNAHS) has been proposed as a method to obtain histological tissue cores while affording the flexibility to obtain specimens even with extreme endoscope angulation. The objective was to compare prospectively these two methods in their ability to obtain specimens for histological assessment and in their diagnostic accuracy, including cytological diagnosis when achieved.
Methods:  Eighty lesions in 77 patients were amenable to transoesophageal, transgastric or transrectal biopsy and were randomized to TCB ( n  = 44) or FNAHS ( n  = 36). Each specimen was assessed for adequacy (scoring system where a score of 0 was no material, 1–2 was considered cytological, and 3–5 was considered histological). Follow-up information was obtained to establish a gold standard final diagnosis.
Results:  The median histological scores for FNAHS and TCB were 2 and 5, respectively. Histological cores were obtained in 95.3% of TCB, as opposed to 27.8% in the FNAHS group ( P  < 0.0001). Although the diagnostic accuracy for TCB was greater than that for FNAHS (88.3% and 77.8%, respectively), this was not statistically significant ( P  = 0.24).
Conclusion:  If histological information is required, TCB is superior to FNAHS. The difference in diagnostic accuracy did not reach statistical significance due to low numbers and the fact that FNAHS often enabled a cytological diagnosis.  相似文献   
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