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DH Mallon M Kostalas FJ MacPherson A Parmar A Drysdale E Chisholm 《Annals of the Royal College of Surgeons of England》2013,95(4):258-262
Introduction
Fine needle aspiration (FNA) is a safe and quick method of diagnosing superficial lumps, which aids preoperative planning. However, FNA of the parotid gland has not gained the widespread acceptance noted in other head and neck lumps. The aim of this study was to determine the ability of FNA of the parotid gland to differentiate benign and malignant disease, and to determine the impact on surgical outcome.Methods
A retrospective analysis of 201 consecutive parotid operations with preoperative FNA in a large district hospital in the UK was performed. The diagnostic characteristics were calculated for benign and malignant disease, and the impact on surgical procedure was determined.Results
In identifying benign disease, FNA has a sensitivity of 85% and a specificity of 76%. In detecting malignant disease, FNA has a sensitivity and specificity of 52% and 92% respectively. A false positive on FNA was associated with a higher incidence of neck dissection.Conclusions
FNA is a useful diagnostic test. However, owing to low sensitivity, it is necessary to interpret it in the context of all other clinical information. 相似文献23.
The interaction of urokinase-type plasminogen activator (uPA) and its receptor, uPAR, on cell surfaces facilitates the generation of cell-bound plasmin, thus allowing cells to establish a proteolytic front that enables their migration through protein barriers. This complex also activates cell signalling pathways that influence cell functions. Clinical studies have identified uPA as an indicator of poor overall survival in patients with colorectal cancer. In the current study, a mouse model of colon cancer, Apc(Min/+), with an additional deficiency of uPA (Apc(Min/+)/Plau-/-) was used to determine the effects of uPA on tumour initiation and growth. Utilizing this model, it was found that the number of tumours was diminished in these mice relative to Apc(Min/+) mice, which correlated with the decreased leukocyte infiltration in the tumours. However, tumour growth was not impeded in Apc(Min/+)/Plau-/- mice, and proliferation and tumour vascularization were, in fact, enhanced in Apc(Min/+)/Plau-/- mice. These latter effects are consistent with a mechanism involving up-regulation of COX-2 expression and Akt pathway activation in Apc(Min/+)/Plau-/- mice. The results from this study suggest that uPA plays dual and opposing roles in regulating lesion development: one early, during the transition from normal epithelia to dysplastic lesions, and another later during tumour growth. 相似文献
24.
Anniek KD Visser Nisha K Ramakrishnan Antoon TM Willemsen Valentina Di Gialleonardo Erik FJ de Vries Ido P Kema Rudi AJO Dierckx Aren van Waarde 《Journal of cerebral blood flow and metabolism》2014,34(1):118-125
The PET tracer [11C]5-hydroxytryptophan ([11C]5-HTP), which is converted to [11C]5-hydroxytryptamine ([11C]5-HT) by aromatic amino acid decarboxylase (AADC), is thought to measure 5-HT synthesis rates. But can we measure these synthesis rates by kinetic modeling of [11C]5-HTP in rat? Male rats were scanned with [11C]5-HTP (60 minutes) after different treatments. Scans included arterial blood sampling and metabolite analysis. 5-HT synthesis rates were calculated by a two-tissue compartment model (2TCM) with irreversible tracer trapping or Patlak analysis. Carbidopa (inhibitor peripheral AADC) dose-dependently increased [11C]5-HTP brain uptake, but did not influence 2TCM parameters. Therefore, 10 mg/kg carbidopa was applied in all subsequent study groups. These groups included treatment with NSD 1015 (general AADC inhibitor) or p-chlorophenylalanine (PCPA, inhibitor of tryptophan hydroxylase, TPH). In addition, the effect of a low-tryptophan (Trp) diet was investigated. NSD 1015 or Trp depletion did not affect any model parameters, but PCPA reduced [11C]5-HTP uptake, and the k3. This was unexpected as NSD 1015 directly inhibits the enzyme converting [11C]5-HTP to [11C]5-HT, suggesting that trapping of radioactivity does not distinguish between parent tracer and its metabolites. As different results have been acquired in monkeys and humans, [11C]5-HTP-PET may be suitable for measuring 5-HT synthesis in primates, but not in rodents. 相似文献
25.
Recent advances and future perspective in neuroimaging in neuropsychiatric systemic lupus erythematosus 总被引:12,自引:0,他引:12
Involvement of the central nervous system (CNS) is one of the most important complications of systemic lupus erythematosus (SLE), occurring in 14-75% of SLE patients. Neurological and psychiatric involvement is mainly manifested as cerebrovascular disease, seizures, cognitive impairment, headaches and psychosis. However, diagnosis of brain involvement in SLE (i.e., neuropsychiatric lupus: NPSLE) as well as understanding of pathogenetic mechanisms still remains a difficult challenge. Although a wide range of neurodiagnostic tools have been used in the last decade to assess CNS involvement, no single technique has proven to be definitive or reliable. Since neurometabolic impairment, neurochemistry and perfusion abnormalities in NPSLE may precede anatomic lesions, new functional techniques such as magnetic resonance spectroscopy, diffusion and perfusion weighted imaging, and magnetization transfer imaging may be useful in order to indentify pathologic changes unrevealed by conventional imaging. So these new diagnostic tools could modify diagnostic and therapeutic approaches to this major unsolved problem, also shedding some light on the physiopathology of CNS disease in SLE. 相似文献
26.
JY Nagata TF Rocha‐Lima BP Gomes CC Ferraz AA Zaia FJ Souza‐Filho A De Jesus‐Soares 《Australian dental journal》2015,60(3):416-420
Immature avulsed teeth are not usually treated with pulp revascularization because of the possibility of complications. However, this therapy has shown success in the treatment of immature teeth with periapical lesions. This report describes the case of an immature replanted tooth that was successfully treated by pulp revascularization. An 8‐year‐old boy suffered avulsion on his maxillary left lateral incisor. The tooth showed incomplete root development and was replanted after 30 minutes. After diagnosis, revascularization therapy was performed by irrigating the root canal and applying a calcium hydroxide paste and 2% chlorhexidine gel for 21 days. In the second session, the intracanal dressing was removed and a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate was placed as a cervical barrier at the entrance of the root canal and the crown was restored. During the follow‐up period, periapical repair, apical closure and calcification in the apical 4 mm of the root canal was observed. An avulsed immature tooth replanted after a brief extra‐alveolar period and maintained in a viable storage medium may be treated with revascularization. 相似文献
27.
Neri S Pulvirenti D Malaguarnera M Cosimo BM Bertino G Ignaccolo L Siringo S Castellino P 《Digestive diseases and sciences》2008,53(3):830-835
Purpose: Hepatorenal syndrome (HRS) is a pre-renal-like dysfunction that generally onsets in cirrhotic patients presenting ascites.
We investigated the improvement of renal function in subjects with hepatorenal syndrome after terlipressin administration
and the survival times after this treatment. Fifty-two patients affected by cirrhosis, with diagnosis of hepatorenal syndrome
were treated with intravenous terlipressin plus albumin (group A) or with albumin alone (group B). Liver and renal function,
plasma renin activity, and aldosterone plasma levels were monitored. Results: Patients from group A showed a significant improvement (p < 0.001) of renal function valued by creatinine rate compared with the results obtained in group B. The probability of survival
was higher in the group A (p < 0.0001). Conclusions: Our results seem to confirm that the administration of terlipressin plus albumin improves renal function in patients with
cirrhosis and type I HRS and that a reversal of hepatorenal syndrome is strongly associated with improved survival. 相似文献
28.
29.
A comparison of Skirrow's, Butzler's, Blaser's, Campy-BAP and Preston media for Campylobacter spp was made using human, animal and environmental specimens. Butzler's medium gave the lowest isolation rate and Preston medium, which was the most selective, the highest isolation rate. Enrichment culture using Preston enrichment broth gave a higher isolation rate than direct plating onto Preston medium. 相似文献
30.
Computer-aided detection in diagnostic mammography: detection of clinically unsuspected cancers 总被引:1,自引:0,他引:1
Butler SA Gabbay RJ Kass DA Siedler DE O'shaughnessy KF Castellino RA 《AJR. American journal of roentgenology》2004,183(5):1511-1515
OBJECTIVE: We had two objectives: to determine the percentage of women presenting with clinical findings whose diagnostic mammogram led to detection of a breast cancer at a site distant from the original clinical complaint and to assess the performance of computer-aided detection (CAD) on diagnostic mammography. MATERIALS AND METHODS: Three institutions contributed consecutive cases in which a mammogram was obtained to evaluate a clinical finding, after which a histologic diagnosis of breast cancer was made. Clinical data and the mammograms were reviewed to determine the nature of the clinical findings and to document the location and characteristics of 212 biopsy-proven cancers in 197 patients who met the study criteria. Standard four-view breast mammograms were then analyzed by a CAD system. RESULTS: The most common clinical finding was a palpable mass (90%, 177/197), with nipple discharge (5%, 9/197), focal tenderness or pain (2%, 5/197), and miscellaneous complaints (3%, 6/197) also noted. Two separate cancers were found in 7.6% (15/197) of the cases. In another 7.6% (15/197) of the cases, the single diagnosed cancer was not at the location of the specific clinical finding. The CAD system correctly marked 87% (26/30) of those cancers that were clinically unsuspected (i.e., not at the location of the clinical finding). CONCLUSION: Breast cancers occurred at locations other than the site of the presenting clinical finding in 15% (30/197) of patients undergoing diagnostic mammography in whom a cancer was detected. CAD identified 87% of these incidentally detected cancers and may therefore be useful as a detection aid to the radiologist when interpreting diagnostic mammograms. 相似文献