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61.
Impression cytology is a simple and painless procedure that allows the collection of the superficial layers of the conjunctival epithelium. Each sample is assigned a grade of epithelial metaplasia, and goblet cell density is calculated in each one. We have studied the superior and temporal bulbar conjuctiva of dry eyes and have compared it with that of normal controls. In normal and dry eyes we find a statistically significant difference both in goblet cell density and grade of metaplasia, between superior and temporal bulbar conjunctiva. the differences in grade of metaplasia and goblet cell density between normal and dry eyes are significant in the superior conjunctiva, but in the temporal conjunctiva we only find significant differences in grade of metaplasia.  相似文献   
62.
H. Ohsaki, T. Hirouchi, N. Hayashi, E. Okanoue, M. Ohara, N. Kuroda, E. Hirakawa and Y. Norimatsu
Diagnostic value of urine erythrocyte morphology in the detection of glomerular disease in SurePath? liquid‐based cytology compared with fresh urine sediment examination Objective: To assess whether the morphology of urine erythrocytes can be an effective tool for distinguishing glomerular disease from lower urinary tract disease in SurePath? liquid‐based cytology (SP‐LBC). Methods: We examined four morphological parameters of erythrocytes: (1) irregular erythrocytes (of all types including fragmented forms) comprising greater than or equal to 20% of erythrocytes; (2) uniform erythrocytes (>80%); (3) doughnut or target‐like shaped (D/T) erythrocytes (≥1%); and (4) acanthocytes (≥1%) in glomerular disease (n = 32) and lower urinary tract disease (n = 20) with SP‐LBC slides in cases that had also been assessed by fresh urine sediment examination. Results: Sensitivity of D/T erythrocytes and acanthocytes (dysmorphic erythrocytes) for glomerular disease were 100% and 87.5%, respectively, with urine sediment examination, and 81.3% and 46.9%, respectively, in SP‐LBC slides. Specificity was 100% for D/T erythrocytes and acanthocytes using either procedure. While irregular erythrocytes were specific for glomerular disease using urine sediment examination, they were seen in 70% of those with lower urinary tract disease using SP‐LBC slides as a result of the deformation of erythrocytes by the fixative. Conclusions: Although the sensitivity of D/T erythrocytes and acanthocytes for glomerular disease was lower in SP‐LBC slides than fresh urine sediment examination, their specificity was equally high. Therefore, urine erythrocyte morphology is useful in the detection of glomerular disease with the SP‐LBC slides. However, morphological features apart from D/T erythrocytes and acanthocytes are not useful in SP‐LBC slides.  相似文献   
63.
Routine audit of breast fine needle aspiration (FNA) cytology specimens and aspirator inadequate rates In an attempt to improve the quality of the breast FNA specimens we instigated a continuing audit of this procedure in this hospital. All FNAs since 1990 have had the following recorded: mode of aspiration, e.g. freehand or image guided, patient presentation (screening or symptomatic), patient diagnostic category, cytological diagnosis and final histological diagnosis. Aspirator performance was assessed by means of the inadequate aspiration rate (IR) of FNAs performed on patients with a final diagnosis of cancer (FDC) and diagnostic category A patients (clinically or radiologically malignant lesions). An ongoing annual review of the performance of all the aspirators was undertaken, all of whom received individual feedback. Counselling and further training were offered where indicated by poor performance. Over the period 1990–1995 a total of 13 537 FNAs were performed by 27 aspirators. The IR on category A and FDC cases over this period was 16.0% and 18.1%. The best performance achieved by an aspirator in a calendar year was an IR of 3.6% with no inadequate specimens in either FDC or category A lesions, and the best performance over the entire period was an average IR of 11.75% and 14.25% for FDC and category A groups, respectively. The overall IR on category A patients ranged from 15.9% to 23.8% and on FDC cases from 12.2% to 21.7%. There was a significant improvement in individual junior aspirator performance when their first year was compared with their last year on the unit. In some cases a deterioration in intra-aspirator performance was observed, from an IR of 6% to 33%. The overall IR rate of the unit remained stable for FDC patients, 15.5% in 1990 compared with 15.1% in 1995. This appeared to be largely due to a high proportion of the aspirations being performed by experienced personnel with consistent IRs. However, concealed within the overall rate there were some poor performers who benefited from counselling and/or further training. These results indicate an important role for audit in identifying poor aspirators who benefit from targeted training and advice, thereby improving the quality of FNA specimens, and ultimately patient care.  相似文献   
64.
K. Chummun, M. Fitzpatrick, P. Lenehan, P. Boylan, E. Mooney and G. Flannelly
Diagnostic and therapeutic dilemma associated with atypical glandular cells on liquid‐based cervical cytology Background: In 2008, the management of women in Ireland with atypical glandular cells changed to immediate referral to colposcopy. The optimal management of these women is unclear. A balance between the detection of occult disease and overtreatment is required. Methods: Our study aim was to document the experience of this policy at the National Maternity Hospital, Dublin. Information from the computerized data management system was analysed with the statistical package SPSS. Results: In 2009, 156 women attended colposcopy following a single atypical glandular cell diagnosis on liquid‐based cytology. The mean age was 41 years. Thirty (19.2%) women had abnormal vaginal bleeding, 31 (19.9%) were smokers and 34 (21.8%) had received previous treatment. The colposcopy was satisfactory in 125 (80.1%) and unsatisfactory in 31 (19.9%). Cervical histology was available for 146 (93.6%) women: 57 excisional procedures and 89 diagnostic biopsies. Abnormal histology was detected in 46 women (31.5%). Four women (2.7%) had invasive cancer, five (3.4%) had adenocarcinoma in situ, 21 (14.4%) had cervical intraepithelial neoplasia (CIN) grade 2 or 3 and 16 (11.0%) had CIN1. No abnormality was detected in 100 women (68.5%), including 35 (61.4%) of those who had undergone excisional procedures. The colposcopic impression in this group was unsatisfactory in 10 women (28.6%), glandular abnormalities in six (17.1%), high‐ and low‐grade changes in 12 (34.2%) and six (17.1%) women, respectively, and normal in one (2.9%). The findings were essentially negative in the remaining 10 women: overall, 30 (19.2%) of the 156 women referred to colposcopy had at least CIN2. Conclusion: This study confirmed significant levels of high‐grade disease in women referred to colposcopy with atypical glandular cells on cytology. Concerns about undetected endocervical disease resulted in high levels of negative excisional biopsies. Alternative strategies, including endometrial sampling, human papillomavirus testing and discussion at clinicopathological meeting, should be considered.  相似文献   
65.
Abstract

A survey of all the 154 scientific publications of Emilio Battaglia (1917–2011) is presented, grouped in three main research interests – plant embryology, cytogenetics in plants and cytological terminology – plus other less relevant contributions. Battaglia's past and present role in these disciplines is briefly discussed, in the light of current research on these topics, partly reviewed also in other contributions of the present Plant Biosystems issue.  相似文献   
66.
The shark Iago omanensis (Triakidae, Selachia) is encountered in large populations in the Gulf of Aqaba, Red Sea, at depths of 150–1,500 m. It is a placental viviparous species, reproductive all year round and giving birth to four (occasionally five) young of 170- to 180-mm total length (TL). Its distribution and morphometrics, as well as histological and cytological changes in the oviducts, were studied. The ratio of weight of the female genital organs to body weight changes from 0.7% in nongravid females to 19.8% in the final stages of pregnancy. The ripe, liberated eggs, which are 11–12 mm long and 5 mm wide, pass through the nidamental gland and settle in the uterus. The embryo attains 9- to 11-mm TL and settles on a protruding ridge of the submucosa, covered with a microvillar endometrium. At this site of attachment, a placenta is formed and the participating uterine endometrium and wall of the yolk sac undergo profound histocytological changes, forming two parts of this organ. Three forms of food provisioning occur in the growing embryos: (1) lecithotrophic, based on yolk transported from the egg to the embryonic gut via the umbilical cord; (2) mixed food provision, during which, in addition to nourishment provided via the umbilicus, food is transported across the placenta through transfer from the female blood vascular system to the embryonic yolk sac via the trophic villi of the yolk sac; and (3) histotrophic, when all yolk reserves have been used and nutrition is provided from the so-called “milk” within the yolk sac, metabolized by the trophic structures of the sac and transported by blood vessels. Despite the gradual utilization of yolk, the yolk sac mass initially increases from 0.5–1.0 cc to 2.0–2.2 cc with the addition of primary and secondary trophic villi until, during the final stages of embryogenesis, it decreases again to 1.4–1.6 cc. Neonate juveniles are 35–40 times heavier than the original eggs. J. Morphol. 236:151–165, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
67.
In the period 1875–1920, a debate about the generality and applicability of evolutionary theory to all organisms was motivated by work on unicellular ciliates like Paramecium because of their peculiar nuclear dualism and life cycles. The French cytologist Emile Maupas and the German zoologist August Weismann argued in the 1880s about the evolutionary origins and functions of sex (which in the ciliates is not linked to reproduction), and death (which appeared to be the inevitable fate of lineages denied sexual conjugation), an argument rooted in the question of whether the ciliates and their processes where homologous to other cellular organisms. In the beginning of the twentieth century, this question of homology came to be less important as the ciliates were used by the British protozoologist Clifford Dobell and the American zoologist Herbert Spencer Jennings to study evolutionary processes in general rather than problems of development and cytology. For them, homology mattered less than analogy. This story illustrates two partially distinct problems in evolutionary biology: first, the question of whether all living things have common features and origins; and second, whether their history and current nature can be described by identical mechanisms. Where Maupas (contra Weismann) made the ciliates qualitatively the same as all other organisms in order to create a cohesive evolutionary theory for biology, Jennings and Dobell made them qualitatively different in order to achieve the same end. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
68.
Objective: To identify in cytology, high‐grade squamous intraepithelial lesions with endocervical glandular extension in cases previously diagnosed as atypical glandular cells (AGC), analyse possible reasons for the diagnostic pitfall and document the frequency of glandular pathology coexisting with high‐grade cervical intraepithelial lesion in histology. Methods: Thirty‐nine ThinPrep® cervical smear (Pap) tests reported as AGC of undetermined significance and showing high‐grade lesions on histology [cervical intraepithelial neoplasia (CIN) 2 or 3, endometrial or extrauterine adenocarcinoma] were reviewed retrospectively to identify the cases of high‐grade squamous intraepithelial lesion with endocervical glandular extension, using the Bethesda 2001 system. Cyto‐histological correlation was performed. Results: A high frequency of diverse glandular pathologies coexisted with high‐grade cervical intraepithelial lesions on histology. This included endocervical glandular extension in 63%, benign glandular pathology in 33% and pre‐neoplastic or malignant glandular pathology (endocervical glandular dysplasia, adenocarcinoma in situ and metastatic breast carcinoma) in 17% cases. On cytology, the sensitivity was 40%, specificity was 80% and positive predictive value was 86% for endocervical gland extension in high‐grade squamous intraepithelial lesions. Conclusions: Special efforts to recognize endocervical glandular extension in high‐grade squamous intraepithelial lesions and glandular neoplasia coexisting with squamous intraepithelial lesions from the heterogeneous category of AGC can contribute to increasing the diagnostic accuracy. The identification of endocervical glandular extension on cervical cytology would alert the gynaecologist to perform a thorough assessment of the endocervix during colposcopy. This could also help to decide on the need to perform deeper conization rather than loop electrosurgical excision procedure to ensure negative margins when colposcopic biopsy shows CIN 2 or 3.  相似文献   
69.
通过重复授粉和75μg.g^-1GA3处理,成功地获得了普通小麦(T.aestium)与瓦维洛夫山羊草(Ae.vavilovii)RM0286,RM0291 2个组合属间杂种的产生及其育性,期间表现出较高的可酱性,杂匀结实率分别39.84%和41.22%,杂种F1植株具有双亲的形态特征,并表现出强的生活力。通过对F1植株小孢子发生和花粉发生和花粉发育的细胞学观察发现,花粉母细胞减数分裂过程异常紊乱  相似文献   
70.
D. L. Ribu, P. W. Shield and J. F. Bligh
The varied presentation of metastatic melanoma in fine needle aspiration cytology of the breast Objective: To identify cytomorphological patterns of metastatic melanoma (MM) in breast fine needle aspiration (FNA) specimens and highlight the differential diagnoses and features most useful in identifying MM. Methods: The clinical, radiological and FNA findings of 16 cases were reviewed. Cytological features evaluated related to cell arrangement, size and shape of cells, nuclear and cytoplasmic features, and the presence or absence of necrosis. Results: The series consisted of 14 females and two males, ranging in age from 24 to 83 years (mean = 50 years). A previous history of melanoma was available in 12/16 (75%) cases at the time of FNA reporting; however the clinical/radiological impression in 4/16 cases was of a breast cyst. The cases were classified into six morphological variants: classical (8/16), pseudopapillary (3/16), spindle‐cell (1/16), melanin‐rich (1/16), pleomorphic (2/16) and lymphoma‐like (1/16). The varying patterns raised a wide range of differential diagnoses; however, discohesion, binucleation and granular cytoplasm were the major features seen in 94% of all cases. In 14/16 cases (88%), plasmacytoid cells, prominent nucleoli and cytoplasmic vacuolation were identified. Melanin and multinucleation were detected in 44% of cases and intranuclear cytoplasmic invaginations in 63%. Necrosis was present in more than half of the cases (56%). Conclusion: MM should be considered in the differential diagnosis of breast FNA specimens when atypical cells are seen that present as plasmacytoid cells in a dispersed or pseudopapillary pattern, or as spindle, pleomorphic or pigmented cells. These features, combined with clinical history and immunocytochemistry, may assist in correctly identifying MM and directing optimal treatment.  相似文献   
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