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综述了扬子鳄消化系统的组织结构、超微结构、内分泌细胞种类与密度分布等,得出3个方面的结论①从消化系统组织和细胞的演化程度看,扬子鳄尚属较原始的类群;②扬子鳄消化系统组织结构、细胞的超微结构和内分泌细胞的种类与分布有较大的特异性;③扬子鳄消化系统组织和细胞的结构与功能同其取食习性是适应的.还对今后的研究工作提出了建议.  相似文献   

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Bronchial metaplasia: observations on its histology and cytology   总被引:1,自引:0,他引:1  
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Continuing progress towards automation of cervical cancer screening requires that criteria for clinical acceptability of automated systems be defined, and that methods be devised for effectively evaluating new technology. The potential roles of automation in cervical cancer detection, performance requirements, instrument evaluation and useful contributions from tuberculosis screening, automated white blood cell differential counting, signal detection theory and decision theory are discussed.  相似文献   

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随着现代技术和信息技术的发展及其在高等学校教学领域中的广泛应用,利用现代网络技术,构建数字化网络多媒体教学平台已经成为新的教学理念。本文对建设适用于以学生自主学习为主导的数字化教学及考评模式进行了初步探讨。  相似文献   

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A retrofit flat panel detector was integrated with a GE DMR+ analog mammography system and characterized using detective quantum efficiency (DQE). Technical system performance was evaluated using the European Guidelines protocol, followed by a limited evaluation of clinical image quality for 20 cases using image quality criteria in the European Guidelines. Optimal anode/filter selections were established using signal difference-to-noise ratio measurements. Only small differences in peak DQE were seen between the three anode/filter settings, with an average value of 0.53. For poly(methyl methacrylate) (PMMA) thicknesses above 60 mm, the Rh/Rh setting was the optimal anode/filter setting. The system required a mean glandular dose of 0.54 mGy at 30 kV Rh/Rh to reach the Acceptable gold thickness limit for 0.1 mm details. Imaging performance of the retrofit unit with the GE DMR+ is notably better than of powder based computed radiography systems and is comparable to current flat panel FFDM systems.  相似文献   

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将最新的科技成果、方法、手段,迅速、准确而有效地运用于知识和技能的传授是现代高等教育发展的必然趋势。组织学与胚胎学属基础医学形态学范畴,是一门以研究正常人体显微结构与功能关系的学科,也是医学生动手实践最早的学科之一。该学科的传统授课方式理论课为课堂讲授,实验课为实验室显微镜观察切片标本。从2007年开始,我们采用了显微数字化互动教学方式进行组织学与胚胎学实验教学。通过几年的实践探索感受颇深。  相似文献   

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OBJECTIVE: To evaluate in detail the morphology of cervical cell samples suspended in the coagulant fixative BoonFix (Finetec, Tokyo, Japan) in liquid-based Papspin slides (Thermo Shandon, Pittsburgh, Pennsylvania, U.S.A) to detect shifts in diagnostic parameters for infections and neoplasia. STUDY DESIGN: Split samples of 1,010 cases were collected. All Papspin slides were scanned with neural network technology. In 849 cases the diagnosis was "within normal limits"; in 22 cases it was preneoplasia. In 151 special cases conventional smears were compared with thin-layer slides. RESULTS: In 85% of the 151 special cases, a shift of the diagnostic parameter was observed in the Papspin slide. The parameter adhesion of inflammatory cells to epithelial cells was easier to discern in 94% of the cases, and adhesion of microorganisms varied 43-100%. Koilocytosis was more visible in 79%. Prominent nucleoli in atypical and malignant cells were enhanced in 50-100% of cases with preneoplasia. The fact that the cells on the Papspin slide were no longer present in diagnostic streaks posed a problem only in the case of follicular cervicitis. CONCLUSION: The shifts in parameters facilitated the diagnostic process. BoonFix permits the screening of liquid-based Papspin slides, which have proven to be well suited to automated neural network scanning.  相似文献   

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Objectives:  Male factors are responsible for about half of all infertility cases. Until recently, testicular biopsy was the standard method to ascertain the aetiology of azoospermia. Fine needle aspiration cytology has gained increasing popularity as a simple and minimally invasive procedure that can help in assessing testicular function accurately. This study was aimed at addressing the question whether testicular fine needle aspiration (FNA) may be used as a first-line diagnostic modality in azoospermia and to assess its usefulness in the diagnostic protocol.
Methods:  The FNA was performed in 78 consecutive azoospermic patients. To obviate sampling errors both testes were aspirated, except when contraindicated. Routine haematoxylin and eosin as well as Romanowsky staining was performed on the smears.
Results:  The smears were categorized on cytological examination into normal spermatogenesis in 35 (50%) patients, Sertoli cells only syndrome in 22 (31.4%) and maturation arrest at the spermatocyte/spermatid level was seen in 13 (18.4%) patients. There were eight (10.2%) cases with scant smears where cytological diagnosis could not be made. A good correlation between cytological smears and histological sections was found in 54 of 58 testes (93.1%) in which histopathological confirmation was available.
Conclusions:  Testicular FNA may be utilized as a first-line investigative modality in patients with azoospermia, provided the procedure is performed and interpreted by experts.  相似文献   

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Background: Immunocytology substantially improves the diagnostic accuracy of conventional cytology in the diagnosis of carcinomatous effusions. Due to the unequivocal characterization of the various cell populations, a sensitivity of 92% and specificity of 100% was achieved by immunocytology, examining samples of 1234 serous effusions. Objective: Cytology plays a central role in the aetiological clarification of serous effusions. The sensitivity of this method for the diagnosis of carcinomatous effusions varies between 40% and 80%. The aim of the present study was to investigate whether immunocytology substantially improves the diagnostic quality of the cytological examination in the diagnosis of carcinomatous effusions. Method: Consecutive serous effusions were examined by conventional cytology and by immunocytology. The immunocytological examination was performed on smears, using a standard panel of three antibodies against pancytokeratin, human epithelial antigen 125 and calretinin. Results: Altogether, 1234 effusion samples were examined. A total of 603 effusions were caused by carcinomas, five by malignant mesotheliomas, 11 by malignant lymphomas and 615 by non‐malignant disorders. In conventional cytology, carcinomatous effusions were correctly diagnosed in 314 samples, corresponding to a sensitivity of 52%. In 31 specimens (5%) tumour cells without further specification were described and in 161 samples (27%) the presence of tumour cells was suspected (84% overall sensitivity). A total of 97 carcinomatous effusions (16%) were diagnosed false‐negatively and 50 (8%) of the 615 non‐malignant effusions false‐positively (92% specificity). In immunocytology, 561 carcinomatous samples were correctly diagnosed, representing a sensitivity of 93%. In six cases (1%) the presence of tumour cells was suspected. A total of 36 carcinomatous effusions (6%) were diagnosed false‐negatively (94% over‐all sensitivity). Out of the 615 non‐malignant specimens, there were no false‐positive diagnoses (100% specificity). Conclusion: Immunocytology is a simple, cost‐effective, routinely practicable method which substantially improves the diagnostic accuracy of conventional cytology in the diagnosis of carcinomatous effusions. Therefore, we recommend the use of immunocytology in all those cases where cytology on its own is not completely unequivocal.  相似文献   

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A. Evered and N. Dudding Accuracy and perceptions of virtual microscopy compared with glass slide microscopy in cervical cytology Objective: To evaluate virtual microscopy in terms of diagnostic performance and acceptability among practising cytologists. Methods: Twenty‐four experienced cytologists were recruited to examine 20 SurePath® cervical cytology slides by virtual microscopy. Diagnostic accuracy was compared with glass slide microscopy using an unbiased crossover experimental design. Responses were allocated a score of one for a correct identification of normal or abnormal (borderline/atypical changes in squamous or glandular cells or worse) and a score of zero for an incorrect response (a normal slide reported as abnormal or vice versa). Perceptions of virtual microscopy were assessed by questionnaire analysis. Results: Participants yielded a total of 285 responses for the virtual slide set and 300 for the glass slide set. The approximate time to screen a virtual slide was 18 minutes, compared with 8 minutes or less for a glass slide. Overall there was no significant difference between virtual microscopy and glass slide microscopy in terms of diagnostic accuracy (P = 0.22). Virtual microscopy under‐performed when images were captured over a narrow focal range (P = 0.01). Diagnostic accuracy of virtual microscopy equalled that of glass slide microscopy when participants were able to focus through the full thickness of the slide images (P = 0.07). The most common difficulties experienced by participants with virtual microscopy were freezing of the computer screen during image download, slow response of the computer during slide movement and, in some instances, ‘fuzzy’ images. Cytologists have a strong preference for glass slides over virtual microscopy despite the overall equal diagnostic performance of the two viewing modalities. Conclusions: Diagnostic accuracy of virtual microscopy can equal that of glass slide microscopy. However, without good computer network connections, wide focal range and software that permits effortless navigation across virtual slides, cytologists are unlikely to be convinced of the utility of this technology for cytology screening and diagnosis.  相似文献   

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The Ontario Laboratory Proficiency Testing Program's testing model and the results of early surveys of cytology laboratories have been previously described. To test consistency and accuracy, the same slides from one survey were recirculated to the same laboratory in the next survey. There was no statistical difference in either the accuracy or consistency in reporting by the various categories of personnel. Analysis of the data by category of diagnosis showed the reporting of "no abnormal cells" and "benign atypia" to be slightly more accurate and "moderate dysplasia" and "severe dysplasia" to be slightly less accurate than the reporting in other categories. Consistency in reporting appeared to be slightly less accurate in severe dysplasia than in the other categories. The analysis, which includes the results from all licensed cytology laboratories in Ontario, provides evidence that, in the reporting of cervical cytologic material, it is feasible to differentiate among the various categories within the spectrum of squamous epithelial abnormalities with a general level of accuracy and consistency that, although satisfactory, is not yet ideal.  相似文献   

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Masson's vegetant hemangioendothelioma is a benign intravascular tumor, sometimes confused with such malignant vascular tumors as angiosarcoma, whose clinical appearance is nonspecific and whose diagnosis can only be established through microscopic examination. The fine needle aspiration (FNA) cytologic findings together with the histologic and immunohistochemical findings of such a tumor in a 22-year-old man are presented. Cytologically, the material obtained by FNA consisted of two distinct populations of cells. One type of cell had large nuclei (sometimes displaced towards the periphery), finely granular chromatin, prominent nucleoli and abundant globular cytoplasm. The second type of cell had spindle-shaped or oval nuclei, granular chromatin and scanty eosinophilic cytoplasm. Although these findings may permit the cytologic recognition of this entity, the aspirate in this case was interpreted as showing a vascular mesenchymal tumor of probable malignancy. Histologic examination of the excised tumor, aided by immunoperoxidase studies for factor VIII antigen that revealed the endothelial nature of the proliferating cells, established the correct diagnosis.  相似文献   

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C. Remondi, F. Sesti, E. Bonanno, A. Pietropolli and E. Piccione
Diagnostic accuracy of liquid‐based endometrial cytology cytology in the evaluation of endometrial pathology in postmenopausal women Objective: The aim of this study was to compare liquid‐based endometrial cytology with hysteroscopy and endometrial biopsy regarding its diagnostic accuracy in a series of postmenopausal women with abnormal uterine bleeding (AUB) or asymptomatic women with thickened endometrium assessed by transvaginal ultrasound as a screening procedure. Methods: Inclusion criteria were: menopausal status; the presence of AUB and/or thickened endometrium assessed by ultrasound (cut‐off 4 mm); a normal Papanicolaou (Pap) smear; and no adnexal pathology at ultrasound. Exclusion criteria were: previous endometrial pathology; and previous operative hysteroscopy. Of 768 postmenopausal women referred to our general gynaecology clinics, 121 fulfilled the inclusion criteria and were recruited to the trial. Twenty‐one refused to participate. Cytological sampling was carried out by brushing the uterine cavity using the Endoflower device with no cervical dilation and the vial was processed using a ThinPrep® 2000 automated slide processor. The slides were stained using a Pap method. Results: In 98 cases with histological biopsies, endometrial cytology detected five cases of endometrial carcinoma, 10 of atypical hyperplasia and 47 of non‐atypical hyperplasia; 36 cases were negative. In two cases cytology was inadequate because of uterine cervical stenosis. Taking atypical hyperplasia or worse as a positive test and outcome, the diagnostic accuracy of the endometrial cytology was 93.5%, with a sensitivity of 92% and specificity of 95%, a positive predictive value of 73% and a negative predictive value of 99%. All the carcinomas were detected by cytology. Only 42% of women with a positive diagnosis were symptomatic. The cytological sampling was well tolerated by all patients. No complication was registered. Conclusions: Liquid‐based endometrial cytology can be considered an useful diagnostic method in the detection of endometrial pathology as a first‐line approach, particularly if associated with transvaginal ultrasound.  相似文献   

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Fine needle aspiration biopsy of an enlarged axillary lymph node in a patient with an intact mammary prosthesis yielded a cellular sample in which there were numerous macrophages containing large cytoplasmic vacuoles, a picture suggestive of granulomatous inflammation of the foreign-body type. Subsequent excision of the lymph node confirmed the diagnosis. Analytical electron microscopy identified the foreign material as silicone. While the cytologic features of silicone lymphadenopathy are diagnostic in the appropriate clinical setting, excision of the lymph node may be advisable to exclude a concomitant malignant neoplasm.  相似文献   

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