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Fine needle aspiration cytology (FNAC) of salivary gland is a popular technique with high sensitivity and specificity. However, the interpretation of FNAC smear of salivary gland lesions is a great challenge to the cytologists. The cytological features of the various tumors of the salivary gland have overlapping cytological features and many other lesions in the head neck region may mimic salivary lesions. Moreover, at times it may be difficult to differentiate benign from malignant tumor of the tumor with same cell of origin. In this article, we have discussed the various problems in the diagnosis of FNAC of the salivary gland lesions. Diagn. Cytopathol. 2015;43:495–509. © 2015 Wiley Periodicals, Inc.  相似文献   
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PURPOSE: To evaluate the role of image-guided fine-needle aspiration cytology (FNAC) of deep-seated lymph nodes. MATERIAL AND METHODS: Image-guided FNACs were performed on 242 patients of deep-seated lymph nodes which included thoracic, retroperitoneal and abdominal nodes. A sterile 3.5/5-MHz micro convex sector probe was used for localisation of the node. The FNAC was performed using a 0.7- to 0.9-mm needle with the stylet removed and attached to a 20-ml syringe and FNAC handle after the needle was visualised in the lesion. For each case a minimum of 4-5 smears were made, and two observers without bias interpreted the smears. RESULTS: A total of 242 patients were aspirated, of which 216 (90%) aspirations were US-guided and the remaining 26 (10%) were CT-guided. Adequate material for cytologic diagnosis was obtained in 208 (86%) patients with a similar diagnostic accuracy. The aspirate material was non-representative or scanty in 34 (14%) patients. The most common cytological diagnosis was tuberculosis/consistent with tuberculosis seen in 108 (45%) patients followed by metastasis (17%) and reactive hyperplasia (10%). Non-Hodgkin lymphoma was diagnosed in 22 (9%) patients. All patients were briefly followed for a period of 1 1/2 to 2 years (mean 1 year). CONCLUSION: Image-guided FNAC has a pivotal role, and is a cost-effective tool for establishing tissue diagnosis as a primary investigative modality. It is also helpful and accurate in follow-up of patients with a known malignant disease, thereby avoiding surgical intervention.  相似文献   
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The objectives of this study were to determine whether antiprogestin therapy or the infusion of human CG to mimic blastocyst transit in the baboon alters heparin-binding EGF-like growth factor expression during the window of implantation. During the menstrual cycle, heparin-binding EGF-like growth factor protein accumulation in the glandular epithelium was low in the proliferative phase and increased to maximal expression on d 5 and 10 postovulation. Stromal cells accumulated high levels of heparin-binding EGF-like growth factor in the proliferative phase, which decreased by d 5 postovulation. These transitional changes in both cell types were delayed when cycling baboons were treated with the antiprogestin ZK 137.316 during the luteal phase. The treatment with human CG had no effect on expression of heparin-binding EGF-like growth factor when compared with cycling baboons on d 10 postovulation and was comparable with that observed on d 18 and 22 of pregnancy. However, the superimposition of the antiprogestin with the human CG treatment also decreased expression in the epithelial cells. In summary, heparin-binding EGF-like growth factor accumulation in the epithelial glands is under the influence of progesterone and does not seem to be influenced by the paracrine secretion of trophoblast CG.  相似文献   
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Dey PM  Burger J  Gochfeld M  Reuhl KR 《Toxicology》2000,146(2-3):137-147
Neurobehavioral testing of herring gull chicks (Larus argentatus) in both laboratory and field studies indicates that lead exposure during critical periods of development causes neurological deficits that may compromise survival in the wild. Accumulating evidence suggests that lead impairs neurodevelopment, in part, by altering the expression of cell adhesion molecules (CAMs) responsible for the proper formation and maintenance of neural structure and synaptic function. We examined the adhesion molecules NCAM, L1, and N-cadherin in gull brains to determine whether these CAMs are altered by lead exposure and might serve as markers of developmental neurotoxicity. One-day-old chicks were collected from nesting colonies and were laboratory housed. On post-hatching day (PHD) 2, chicks were given 100 mg/kg lead acetate or saline (intraperitoneally). Birds were killed on PHD 34, 44, or 55 (blood-lead levels averaged 27.4, 20.8, and 19.5 microg/dl, respectively). Brains were removed and stored at -70 degrees C until analysis. Expression of CAMs was determined in synaptosomal preparations by Western blotting and the activity of NCAM-associated sialyltransferase (ST) was determined in purified whole brain golgi apparatus. Elevation in synaptosomal polysialylated NCAM expression and a significant increase in golgi ST activity was observed in lead-treated animals at PHD 34. Reductions in synaptosomal N-cadherin were observed at PHD 34 and 44, while L1 expression appeared unaffected by lead at any time-point. By 55 days post-hatching, no differences in N-cadherin expression, polysialylated NCAM expression or NCAM-associated ST activity were seen in lead-treated animals as compared with age-matched control animals. Lead-induced disruption of CAM expression during early neurodevelopment may contribute to behavioral deficits observed in herring gulls in both the laboratory and the field, and may serve as a marker for heavy metal exposure during postnatal development.  相似文献   
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