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991.
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In April 2006, a 55-year-old female presented with a thyroid mass and multiple skin nodules on scalp, forehead and neck. Fine needle aspiration cytology of thyroid mass and multiple skin nodules show tumor cells clusters in a repetitive microfollicular pattern on May-Grunwald-Giemsa stain suggestive of follicular thyroid carcinoma with metastasis to skin. Although follicular carcinoma have a propensity for vascular invasion and hematogenous dissemination, skin is not commonly involved. Only a few cases of cutaneous metastasis from follicular thyroid carcinoma are reported in the English language literature.  相似文献   
994.
The most common sites of cysts caused by hydatid disease are liver and lung. In the absence of visceral involvement, the disease rarely affects musculoskeletal and soft tissues. In such locations, hydatid cyst mimics commoner soft tissue tumors. A 12-year-old girl presented with a gradually increasing painless right shoulder swelling. With a clinical diagnosis of lipoma, fine needle aspiration cytology was performed, which showed cytomorphological features of a hydatid cyst. Another patient, a 20-year-old man, presented with a right paravertebral soft tissue swelling. Radiological investigations did not reveal any bony abnormality or features of intervertebral disc prolapse and thus, a clinical diagnosis of a paravertebral soft tissue tumor was considered. Fine needle aspiration from the soft tissue swelling showed laminated membrane, compatible with hydatid cyst. No visceral involvement was detected in either of the cases. Parasitic cysts, although rare, should be kept in the list of cytological differential diagnosis of soft tissue lesions. Occurrence of hydatid cyst in a soft tissue location is extremely rare. Aspiration cytology can be used efficiently in the diagnosis without the risk of spillage of contents.  相似文献   
995.
The lung must maintain a high threshold of immune 'ignorance' to innocuous antigens to avoid inflammatory disease that depends on the balance of positive inflammatory signals and repressor pathways. We demonstrate here that airway macrophages had higher expression of the negative regulator CD200 receptor (CD200R) than did their systemic counterparts. Lung macrophages were restrained by CD200 expressed on airway epithelium. Mice lacking CD200 had more macrophage activity and enhanced sensitivity to influenza infection, which led to delayed resolution of inflammation and, ultimately, death. The administration of agonists that bind CD200R, however, prevented inflammatory lung disease. Thus, CD200R is critical for lung macrophage immune homeostasis in the resting state and limits inflammatory amplitude and duration during pulmonary influenza infection.  相似文献   
996.
Renal cell carcinoma (RCC) is characterized by an unpredictable clinical behavior. It has a tendency for early metastasis, which, at times is the initial presentation and therein poses a diagnostic challenge. We present a rare case of a disseminated RCC in a 15-year-old girl, who primarily presented with an occipital soft tissue mass. Computed tomography (CT) of the head revealed a soft tissue mass in the scalp, eroding the occipital bone and extending intracranially. Biopsy examination showed overlapping features of an alveolar soft part sarcoma (ASPS) and a RCC. Immunohistochemistry (IHC) showed diffuse positivity for CD10 and focal positivity for vimentin. Cytokeratin (CK) and epithelial membrane antigen (EMA) were negative. The patient was recommended a clinical ‘work-up’ to rule out a possible primary in the kidneys. Her CT scan abdomen unraveled a large, lobulated, heterogeneous cystic mass, involving the middle and upper pole of the left kidney. Diagnosis of a metastatic RCC was ascertained. The present case represents a rare manifestation of a RCC metastasizing at an unusual location i.e. calvarium in the youngest patient known, so far and masquerading a primary ASPS. It also highlights the value of clinico-patho-radiological correlation, including CD10 as a useful IHC marker in diagnosing a RCC in young patients, especially when histopathological features overlap with ASPS.  相似文献   
997.
998.
Background Ductal lavage (DL) allows repeat sampling of breast epithelium for serial observation in a chemoprevention setting; however, the reproducibility of duct cannulation, cell yield and cytology has not been addressed. Methods We conducted a Phase 2 trial, wherein high risk women chose tamoxifen treatment or observation following an entry DL procedure. We present data from the non-intervention arm of our study to assess the reproducibility of cannulation, cell yield, and cytologic diagnosis from DL of the same duct at two time-points. Inter-observer variability was assessed by a blinded review of Papanicoloau-stained slides by two cytopathologists. Results Sixty-five women had a successful lavage of 187 ducts at baseline and chose observation; 63/65 (97%) had a successful lavage 6 months later. Successful recannulation of the same duct was accomplished in 63 women (97%) and162 ducts (87%). Total epithelial cell yields ≥100 were obtained from 57/65 women (88%) and 129/187 ducts (69%) at baseline, and 46/63 women (73%) and 80/162 ducts (49%) at both time-points. Cytologic diagnosis was reproducible in 27/63 (43%) women and 77/162 (48%) ducts. Inter-observer variability for cytologic diagnosis between two observers showed good agreement (κ = 0.62). Conclusions Recannulation and lavage of the same duct after a 6 month interval can be achieved with high frequency; however, reproducibility of cell yield and cytologic findings from the same duct is sub-optimal, leading to significant attrition of evaluable subjects. The utility of DL for the serial monitoring of breast epithelium is therefore limited.  相似文献   
999.
1000.
Neuregulin 1 (NRG1) has been implicated in several disorders including breast cancer, multiple sclerosis, and schizophrenia. Also, recent evidence suggests that NRG1 may play a role in regulation of inflammation and immune system response. We therefore hypothesized that a schizophrenia-associated missense mutation (valine to leucine) we identified within the transmembrane region of NRG1 would also be linked to immune dysregulation. We used plasma samples from families carrying the mutation to measure levels of antibodies to 41 autoimmune markers and six cytokines (IL-1b, IL-6, IL-10, IL-8, IL-12p70, and TNF-α) and used these levels as quantitative traits to evaluate association with the NRG1 mutation, using FBAT. Next, we used Epstein–Barr virus-transformed B cells from heterozygous mutation carriers and wild-type individuals to evaluate protein and mRNA cytokine expression in vitro using quantitative PCR and ELISA assays. In vivo, increased levels of 25 autoimmune markers as well as elevated levels of cytokines were significantly associated with the NRG1 mutation. In vitro, we observed a significant increase in protein secretion levels of IL-6, TNF-α, and IL-8 in mutation carriers compared with controls. At the mRNA level, we observed a significant increase in IL-6 expression, while IL-4 levels appeared to be down-regulated in heterozygous individuals compared with wild-type controls. This is the first report of association of a NRG1 mutation with immune dysregulation. This study could contribute towards understanding the role of NRG1 in the pathogenesis of schizophrenia and other disorders in which inflammation plays an important role.  相似文献   
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