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61.
The presence of squamous metaplasic cells is an uncommon finding in fine-needle aspiration (FNA) biopsies of the breast. We report that FNA smears containing atypical squamous metaplastic cells derived from the lining of seroma-type cavities following lumpectomy and irradiation in patients with breast cancer can be a potential pitfall for a false-positive diagnosis of recurrent malignancy. Four fine-needle breast aspirates from two adult patients with previous histories of invasive breast carcinoma were retrieved. One specimen was from a 56-yr-old female, while the remaining three FNAs aspirates were from a 75-yr-old female. Both patients presented with indurated cystic lesions arising at irradiated lumpectomy sites. The cytospins from the 56-yr-old patient showed markedly atypical cells having enlarged, degenerating, hyperchromatic nuclei and surrounding dense cytoplasm with sharp borders that were suspicious for carcinoma. A mastectomy revealed irradiation changes and atypical squamous metaplastic cells lining a cystic cavity consistent with a seroma, but there was no evidence of residual cancer. After three aspirations yielded "atypical" diagnoses, the second patient underwent core needle biopsies that also revealed changes consistent with a seroma cavity lined by atypical squamous metaplastic cells. We believe this is the first report of squamous metaplasia occurring in a seroma cavity following lumpectomy and irradiation of the breast. The squamous metaplastic cells in aspirates of these cystic lesions may display significant cellular atypia that can potentially result in a false-positive diagnosis of malignancy. 相似文献
62.
Targeted gene disruption of murine CD7 总被引:2,自引:0,他引:2
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig
superfamily. CD7 is a marker of mature human T cells and NK cells, and is
expressed early in their development. Cross-linking CD7 positively
modulates T cell and NK cell activity as measured by calcium fluxes,
expression of adhesion molecules, cytokine secretion and proliferation. CD7
associates directly with phosphoinositol 3'-kinase, and CD7 ligation
induces production of D-3 phosphoinositides and tyrosine phosphorylation.
Severe combined immunodeficiency has been associated with a lack of
lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog
is encoded by a single gene on chromosome 11. In order to characterize the
role of CD7 in lymphocyte development and function we have eliminated the
CD7 gene by targeted disruption. CD7- deficient mice display normal
histology of thymus and spleen, normal lymphocyte populations in primary
and secondary lymphoid tissues, and normal serum Ig levels. Specific
antibody responses after immunization with T-dependent and T-independent
antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient
lymphocytes respond normally to T cell mitogenic and allogeneic stimuli,
and display normal NK cell cytotoxicity.
相似文献
63.
Afef Dellai Audrey Laroche‐Clary Lamia Mhadhebi Jacque Robert Abderrahman Bouraoui 《Drug development research》2010,71(7):412-418
The fact that conventional and newly emerging treatment procedures like chemotherapy, catalytic therapy, photodynamic therapy, and radiotherapy have not succeeded in reversing the outcome of many cancers alternative treatment options has been explored. This study documents the identification of component(s) from the Mediterranean sponge, Spongia officinalis that have anti‐inflammatory and antiproliferative activities. In the present study we investigated the efficacy of a crude extract and its semi‐purified fractions (F1–F3) of the defensive secretion from Spongia officinalis for in vivo anti‐inflammatory activity using the carrageenan‐induced paw edema assay in rats and their in vitro antiproliferative effects against three human cancer cell lines (A549, lung cell carcinoma; HCT15, colon cell carcinoma; and MCF7, breast adenocarcinoma). Among the series, the crude extract exhibited interesting anti‐inflammatory activity associated with significant growth and concentration‐related colony inhibitory effects against the three cell lines. The fractions F2 and F3 showed, respectively, interesting anti‐inflammatory and antiproliferative activities in a dose‐dependent manner. The purification and the determination of chemical structures of compounds of these active fractions are under investigation. Drug Dev Res 71: 412–418, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
64.
Patrícia De Souza Rossignoli Oduvaldo CM Pereira Agnaldo B Chies 《Clinical and experimental pharmacology & physiology》2010,37(3):368-374
1. Orchidectomy results in long‐term testosterone deprivation similar to that observed in male clinical pathologies, such as hypogonadism and age‐related reductions in plasma testosterone concentrations. Although the vascular effects of these sorts of hormone deprivations are known in arteries, they have not been studied to the same extent in veins. 2. The aim of the present study was to determine the effect of orchidectomy, with or without subsequent testosterone replacement (started 23 days after orchidectomy; 10 mg/kg, i.m., testosterone propionate once every 5 days for 3 weeks), on responses of rat isolated portal veins and vena cavae to exogenous phenylephrine (PE). Isolated vessels were mounted in an organ bath and concentration–response curves constructed to PE (10?10–10?4 mol/L), endothelin (ET; 10?10–10?5 mol/L) and KCl (10?2–1.2 × 10?1 mol/L; as a control). 3. Orchidectomy had no effect on contractile responses of either the portal vein or vena cava to KCl. However, orchidectomy enhanced the maximum response (Rmax) of the portal vein, but not the vena cava, to PE. Testosterone replacement had no effect on these responses. The effects of orchidectomy on the Rmax to PE in portal veins were not altered by the nitric oxide synthase inhibitor NG‐nitro‐l‐ arginine methyl ester (10?4 mol/L) alone or combined with 10?5 mol/L indomethacin (a non‐selective cyclo‐oxygenase inhibitor), but they were abolished following treatment of isolated vessels with the ETA and ETB receptor antagonists BQ‐123 and BQ‐788 (both at 10?6 mol/L). Orchidectomy did not alter portal vein responses to the application of exogenous ET. 4. The results of the present study indicate that orchidectomy‐induced decreases in plasma testosterone can increase the venoconstrictor effects of PE on the portal vein and that this effect involves activation of both ETA and ETB receptors by locally produced ET. 相似文献
65.
Although there has been increasing recognition of psychiatric comorbidity in epilepsy, most research and attention in this area has focused on depression. However, comorbid anxiety in epilepsy is highly prevalent, affecting more than 40 % of patients in some reports. Many important outcomes are significantly impacted by anxiety in epilepsy, including quality of life, mortality, and seizure status. Recent evidence from epidemiologic studies suggests a bidirectional association of anxiety and epilepsy, and there is mounting evidence for possible common pathophysiology underlying anxiety and epilepsy. Despite this importance, anxiety is under-recognized and undertreated in clinical practice. A variety of anxiety symptoms are seen in epilepsy, including symptoms exclusively before, during or after seizures (peri-ictal anxiety), symptoms resembling primary anxiety disorders, and anxiety directly related to epilepsy or its treatment. Key therapeutic approaches include pharmacotherapy or cognitive behavioral therapy for most forms of interictal anxiety and better seizure control for peri-ictal anxiety. 相似文献
66.
Background
The Dai people, one of the ethnic minorities in China, have a population of 1,260,000. They have the same origin as one of the main ethnic groups of Laos and Thailand. Most of the Dai live in Yunnan province, which is located in the less-developed southwestern part of China. This study aimed to describe the oral health status of Dai preschool children in China and the factors that influence their oral health status.Methods
An oral health survey was performed between 2011 and 2012 to select Dai five-year-old children using multi-stage stratified sampling in Yunnan. Their dental caries experience was measured using the “dmft” index, and severe caries was assessed using the “pa” index, which is modified from the “pufa” index. Oral hygiene status was assessed using the visual plaque index (VPI). A questionnaire to study the children’s socio-demographic background and oral health-related behaviours was completed by the children’s parents.Results
A total of 833 children were examined. Their caries prevalence was 89% and 49% of the children had carious tooth with pulp involvement. The mean (SD) dmft score was 7.0 (5.3). Higher dmft scores were found among children who were girls, were currently bottle-fed, took daily sweet snacks, had higher VPI scores, and had visited a dentist within the last year.Conclusions
The caries prevalence and experience of the five-year-old Dai children in Yunnan, China was high, and almost half had severe caries. The caries experience was associated with gender, snack habits, dental visit habits, and oral hygiene status.67.
68.
Andre C. Felicio MD PhD Katherine Dinelle MSc Pankaj A. Agarwal MD DNB DM Jessamyn McKenzie LPN Nicole Heffernan RN Jeremy D. Road MD Silke Appel‐Cresswell MD Zbigniew K. Wszolek MD Matthew J. Farrer PhD Michael Schulzer MD PhD Vesna Sossi PhD A. Jon Stoessl CM MD FRCPC 《Movement disorders》2014,29(9):1197-1201
69.
In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population. 相似文献
70.
Stemmler BJ Paulson EK Thornton FJ Winters SR Nelson RC Clary BM 《AJR. American journal of roentgenology》2004,183(6):1551-1557
OBJECTIVE: We sought to evaluate the accuracy of dual-phase MDCT angiography for assessing the liver before hepatic resection and to compare 2D and 3D images for quality and arterial branch visualization. MATERIALS AND METHODS: Sixty-three patients with colorectal metastases (n = 30), hepatocellular carcinomas (n = 13), giant hemangiomas (n = 5), and other lesions (n = 15) underwent dual-phase MDCT using either a LightSpeed QX/i 4-MDCT (n = 31) or LightSpeed QX/i Ultra 8-MDCT (n = 32) scanner. Contrast material (150 mL of Isovue 370 [iopamidol]) was injected at a rate of 5 mL/sec. The arterial phase images were rendered on a workstation to obtain 3D MDCT angiograms that were assessed by two reviewers who were blinded to the surgical findings. Arterial anatomy was categorized according to the Michels classification. The reviewers assessed the 2D and 3D images for quality, arterial branch visualization, and differences between the 4- and 8-MDCT images. In the 43 patients who underwent resection, imaging findings were correlated with intraoperative findings. RESULTS: The anatomy of hepatic arteries in the 63 patients was classified as follows: Michels type I, 51 patients (80.9%); type III, four patients (6.3%); type V, five patients (7.9%); and types VII, VIII, and IX, one patient (1.6%) each. In 40 (93%) of 43 patients, the surgical findings concurred with MDCT findings. Three discrepancies were due to failure to identify small accessory left hepatic arteries. Branch visualization and image quality of the 2D images were superior to those of the 3D images. No significant difference was found between the 4- and 8-MDCT images in branch visualization and image quality. CONCLUSION: Three-dimensional MDCT angiography is accurate for classification of hepatic arterial anatomy before hepatic resection. Although 2D data sets show small arteries to better advantage than 3D MDCT angiograms, the 3D MDCT angiograms provide a useful overview of hepatic anatomy. 相似文献