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81.
大鼠肺微血管内皮细胞培养及其粘弹性研究   总被引:4,自引:0,他引:4  
为了建立肺微血管内皮细胞培养方法 ,研究肺微血管内皮细胞粘弹性。我们取大鼠肺周边组织 (宽度不应大于 1.5 mm) ,将组织剪成 1.5 mm× 1mm× 1mm的组织块 ,贴入无菌的 2 5 cm3培养瓶 ,每瓶 10~ 15块 ,同时加入含 2 0胎牛血清、肝素 90 U/ml、L-谷氨酰胺 4mmol、青霉素 10 0 U/ml和链霉素 10 0 μg/ml的 DMEM培养基 3ml,放入 37℃二氧化碳培养箱中静置培养 ;8h后翻转培养瓶 ,6 0 h后取出肺组织块 ,接着继续培养 2~ 4d后进行传代。最后消化分离肺微血管内皮细胞 ,用微管吸吮系统研究肺微血管内皮细胞粘弹性。结果显示 :肺微血管内皮细胞通过倒置相差显微镜观察 ,细胞呈鹅卵石镶嵌状排列 ,状如梭形或多角形 ,大小均匀 ,胞核清晰 ,呈卵圆形 ,胞浆丰富 ; 因子相关抗原免疫荧光染色呈阳性 ;肺微血管内皮细胞弹性模量 K1 =49.3± 9.2 Pa、K2 =73.2±2 4.8Pa、粘性系数 μ=19.2± 7.2 Pa.s。这些结果表明用组织块法培养肺微血管内皮细胞是可行的 ,肺微血管内皮细胞表现出较大的刚性  相似文献   
82.
Ameloblastic fibroma of the jaw is a rare, benign mixed odontogenic tumor, having little tendency for local invasion and a low recurrence rate. Cytologic distinction from ameloblastoma, ameloblastic fibrosarcoma, and intraosseous adenoid cystic carcinoma is necessary, in view of the different biologic behavior. A painful, slow-growing swelling of the jaw in a 5-yr-old child clinicoradiologically considered as a benign cystic lesion was aspirated. Sheets of small monomorphic epithelial cells with peripheral palisading by columnar cells were seen on cytology smears. The striking feature was central hyaline globules in some tubules. A cytologic possibility of adenomatoid odontogenic tumor was suggested. Histopathology, however, confirmed it to be an ameloblastic fibroma.  相似文献   
83.
The progressive reduction in p27(Kip1) (p27) protein immunohistochemical staining with increasing histological grading is a well-established finding occurring in breast cancer, and its role as diagnostic complement and prognostic marker has been thoroughly evaluated. To clarify whether this test may be applied to breast cytopathology, we performed p27 immunostaining on fresh fine-needle cytology (FNC) samples from 10 benign and 40 malignant breast lesions. On average, p27 immunostaining was significantly lower in carcinomas than in benign lesions (P < 0.005). In particular, among carcinomas, p27 immunostaining progressively reduced from well-to poorly differentiated lesions (G1 vs. G2, P < 0.05; G1 vs. G3, P < 0.001; G2 vs. G3; P < 0.001). A similar trend was noted in a subgroup of 20 matched FNCs and histological samples of breast carcinomas, when p27 immunostaining on FNCs was stratified according to the histological grading (G1 vs. G2, P = 0.18; G1 vs. G3, P < 0.05; G2 vs. G3, P < 0.05). In addition, p27 immunostaining on FNCs showed a good positive correlation with that on histology (Spearman R = 0.58; P < 0.01), with a diagnostic concordance between samples of 85%, by using the standard 50% positive cell cutoff. Taken in concert, our data suggest that p27 immunostaining is a reliable marker of tumor cell differentiation in breast cytopathology as well as in histopathology. Accordingly, staining FNCs for p27 may be an useful complement in addition to cytological grading in the preoperative assessment of breast cancer.  相似文献   
84.
Signet-ring lymphoma is a rare entity in which the synthesis or secretion of immunoglobulins is impaired, producing a signet-ring appearance to the lymphoma cells. A case of this type of lymphoma is described, and the cytologic aspects of the cells obtained from the fixative fluid are described.  相似文献   
85.
Fine-needle aspiration (FNA) of the lymph node was done in five patients with histiocytic necrotizing lymphadenitis (Kikuchi's disease). In four patients, the aspirates were found to have many small and large atypical lymphocytes, some reactive, phagocytic histiocytes, and intense extracellular debris. Neutrophils, plasma cells, or multinucleated giant cells were not seen. These cytologic findings were considered diagnostic for Kikuchi's disease. In one patient, the aspirate did not show significant histiocytosis or tissue necrosis and was considered nondiagnostic. In patients with both typical clinical features and characteristic cytologic findings in the lymph node aspirates, FNA of the lymph node alone will suffice for diagnosis. In those patients with typical clinical features but nondiagnostic findings in the FNA aspirates, the diagnosis of Kikuchi's disease may have to be established either on repeated nodal FNA or on lymph node biopsy.  相似文献   
86.
A case of multiple myeloma diagnosed by fine-needle aspiration (FNA) biopsy and confirmed by laboratory studies in a patient with a history of renal-cell carcinoma is presented. The patient was diagnosed with renal-cell carcinoma of the right kidney and a radical nephrectomy was performed. Eighteen months after this diagnosis was made, the patient developed chest wall pain and was found to have osteolytic bone lesions of the ribs and vertebral bodies. FNA of an osteolytic rib lesion disclosed multiple myeloma. Additional laboratory studies confirmed the diagnosis of multiple myeloma. This case report demonstrates the value of FNA as a diagnostic tool for the follow-up of cancer patients, the subsequent discrimination between metatastic lesions and a second primary malignancy, and the cytology of multiple myeloma.  相似文献   
87.
A 53-yr-old woman presented with a left upper quadrant abdominal mass attached to the body of the pancreas. Fine-needle aspiration (FNA) yielded cyst fluid containing numerous benign, mature squamous cells, keratin debris, and inflammatory cells. The diagnosis of dermoid cyst was subsequently rendered on the resected specimen. The cytologic and histologic features are presented. FNA cytology proves to be a valuable diagnostic adjunct in the preoperative evaluation of a patient with dermoid cyst of the pancreas.  相似文献   
88.
The incidence of pancreatic adenocarcinoma is increasing and it is usually unresectable at the time of diagnosis. Consequently, fine-needle aspiration biopsy (FNAB) is being used more frequently for diagnosis. The reported sensitivity of diagnosing pancreatic adenocarcinoma by FNAB has varied between 50% and 100%. In an attempt to increase the diagnostic sensitivity, we retrospectively reviewed a series of pancreatic FNABs. Fifteen cytologic criteria were evaluated in 78 patients who had pancreatic FNABs. Of these patients, 49 had primary adenocarcinomas and 29 had benign, non-neoplastic lesions. Using a stepwise logistic regression analysis we identified three key cytologic criteria for this diagnosis. Our study identified anisonucleosis (P = 0.001), large nuclei (P = .007), and nuclear molding (P = .03) as the significant cytologic features for diagnosing pancreatic adenocarcinoma. In combination, these three criteria had a sensitivity of 98% and a specificity of 100%.  相似文献   
89.
Pancreatic somatostatinoma is a rare pancreatic endocrine neoplasm representing as little as 1% of pancreatic endocrine neoplasms (PENs). The histologic features of this tumor are like those of other PENs, except that it commonly forms acinar structures and often has cells with abundant, granular cytoplasm. We have recently encountered two of these neoplasms sampled by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA). We discuss the cytologic and immunohistochemical findings of these two cases and the cytologic similarities these neoplasms share with pancreatic acinar-cell carcinoma (PACC). We review the cytologic features of PEN and PACC and discuss the importance of cell block immunohistochemistry in the diagnosis of pancreatic neoplasia sampled by EUS-guided FNA.  相似文献   
90.
Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon lesion usually found in premenopausal women. Histologically, it is characterized by complex, anatomosing, empty slit-like spaces in a dense collagenous stroma. These pseudoangiomatous spaces are lined by monomorphic spindle cells of myofibroblastic differentiation. Cytological features of PASH are rarely discussed and reported, and may pose diagnostic challenge to surgical pathologists. Two cases of PASH are reported with emphasis on the FNAC features and cytologic differentiation from other benign fibroepithelial lesions.  相似文献   
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