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Follicular lymphoma is a B cell malignancy prone to transformation into a large cell diffuse histology. This progression may be multi-clonal as determined by IgH rearrangement. Similar multi-clonal occurrences have been described in immunocompromised patients. However, the lymphoma cells remain predominantly of B cell type. Rarely, composite lymphomas with diffuse T cell histology have been reported arising from follicular lymphoma. The development of T cell leukaemia in a patient with a pre-existing B cell malignancy is an extremely rare event. The occurrence of T cell acute lymphoblastic leukaemia (T-ALL) following follicular lymphoma (FL) has not previously been reported. We report a case of Philadelphia positive (Ph+) T cell ALL developing in a patient who previously had FL which may give some insight into the cell of origin and the defects responsible for malignant transformation of the lymphocytes.  相似文献   
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To evaluate the safety, tolerability, efficacy, pharmacokinetics and pharmacodynamics of the humanised antiepidermal growth factor receptor monoclonal antibody matuzumab combined with epirubicin, cisplatin and capecitabine (ECX) in patients as first-line treatment for advanced oesophagogastric cancer that express epidermal growth factor receptor (EGFR). This was a phase I dose escalation study of matuzumab at 400 and 800 mg weekly and 1200 mg every 3 weeks combined with ECX (epirubicin 50 mg m−2, cisplatin 60 mg m−2 on day 1 and capecitabine 1000 mg m−2 daily). Patients were treated until disease progression, unacceptable toxicity or for a maximum of eight cycles. Twenty-one patients were treated with matuzumab at three different dose levels (DLs) combined with ECX. The main dose-limiting toxicity (DLT) was grade 3 lethargy at 1200 mg matuzumab every 3 weeks and thus 800 mg matuzumab weekly was the maximum-tolerated dose (MTD). Other common toxicities included rash, nausea, stomatitis and diarrhoea. Pharmacokinetic evaluation demonstrated that the coadministration of ECX did not alter the exposure of matuzumab. Pharmacodynamic studies on skin biopsies demonstrated inhibition of the EGFR pathway. Objective response rates of 65% (95% confidence interval (CI): 43–82), disease stabilisation of 25% (95% CI: 11–47) and a disease control rate (CR+PR+SD) of 90% were achieved overall. The MTD of matuzumab in combination with ECX was 800 mg weekly, and at this DL it was well-tolerated and showed encouraging antitumour activity. At the doses evaluated in serial skin biopsies, matuzumab decreased phosphorylation of EGFR and MAPK, and increased phosphorylation of STAT-3.  相似文献   
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Accurate pregnancy dating is vital to obstetric management. However, first trimester fetal charts commonly used in Australia rely on data reported more than three decades ago. This study reports first trimester dating and growth charts for crown‐rump length between 5 and 14 weeks of gestation and biparietal diameter between 9 and 14 weeks of gestation on an Australia population using modern real‐time ultrasound equipment. All consenting eligible women attending a large Sydney clinic for first trimester ultrasound between March 2005 and December 2006 were recruited. Measurements were carried out to Australasian Society for Ultrasound in Medicine standard protocols. Statistical analyses were undertaken using polynomial regression models and thorough diagnostic checks made. Overall 396 eligible women consented to the study, with 268 between 9 and 14 weeks of gestation. The average participant age was 34 years (range 22–45 years), 371 and all yielded valid biometry measurements. Equations, means and 90% reference intervals for crown‐rump length measurements and biparietal diameter measurements were derived using polynomial regression models. Thorough residual and diagnostic checks were made. Once validated by others, we believe they will warrant consideration for use by Australasian Society for Ultrasound in Medicine.  相似文献   
108.
Specific inhibitors of cyclooxygenase 2 (COX-2) have been approved for the treatment of osteoarthritis and rheumatoid arthritis. Unlike nonsteroidal anti-inflammatory drugs, specific COX-2 inhibitors do not inhibit platelet activation. However, these agents significantly reduce systemic production of prostacyclin. As a result, theoretical concerns have been raised that specific COX-2 inhibitors could shift the hemostatic balance toward a prothrombotic state. Patients with connective tissue diseases (CTD), who may be predisposed to vasculopathy and thrombosis, often have arthritis or pain syndromes requiring treatment with antiinflammatory agents. Herein we describe 4 patients with CTD who developed ischemic complications after receiving celecoxib. All patients had a history of Raynaud's phenomenon, as well as elevated anticardiolipin antibodies, lupus anticoagulant, or a history compatible with antiphospholipid syndrome. It was possible to measure a urinary metabolite of thromboxane A2 in 2 of the patients as an indicator of in vivo platelet activation, and this was markedly elevated in both. In addition, the patients had evidence of ongoing inflammation as indicated by elevated erythrocyte sedimentation rate, hypocomplementemia, and/or elevated levels of anti-DNA antibodies. The findings in these 4 patients suggest that COX-2 inhibitor-treated patients with diseases that predispose to thrombosis should be monitored carefully for this complication.  相似文献   
109.
BACKGROUND: Iron stores in the body are thought to be regulated by a mechanism associated with the rate of iron absorption from the diet, with no significant role played by iron excretion. We report the existence of an iron excretory process that results in the loss of significant amounts of liver iron. METHODS AND RESULTS: Rats were fed 3% carbonyl iron for 9 weeks, which resulted in a 20-fold increase in liver non-haem iron. When the rats on this iron-loaded diet were switched to a low iron diet for 2 and 7 days, liver non-haem iron levels fell 30% and 45%, respectively. A similar fall in transferrin-bound plasma iron was also seen. As the liver iron had not redistributed to other body compartments, it was concluded that the iron had been excreted and that the excreted iron represented a loss of 22% and 28% in total body non-haem iron over 2 and 7 days, respectively. Ligation of the common bile duct in iron loaded rats that had been switched to the iron-deficient diet was accompanied by a similar loss of liver iron and also hepatocellular damage. In addition, measurement of enterocyte iron levels showed that only approximately 5% of the total iron excreted was found in these cells. CONCLUSION: Neither bile nor enterocytes play a significant role in iron excretion. The similarity in the degree of fall in transferrin-bound iron levels with a change in diet suggests that iron excretion involves the uptake and excretion of transferrin bound-iron, possibly by goblet cells. The observed hypertrophy of the intestinal mucosa associated with carbonyl iron feeding may facilitate hypersecretion of mucous and the excretion of this iron.  相似文献   
110.
Two patients aged 11 and four years, were accidentally given a 10-fold overdose of intrathecal methotrexate while being treated for malignant disease. Neither patient developed any signs of neurotoxicity and exchange of lumbar cerebro-spinal fluid was started 3 and 5 h later, respectively. In one of the patients, who received 120 mg of methotrexate intrathecally, 31% of the given dose was recovered during 2 h of cerebrospinal fluid exchange that was started 3 h after the accidental overdosage. No sequelae were observed in any of the patients. Cerebrospinal fluid exchange is safe and can be recommended in all cases of intrathecal methotrexate overdosage. Ventriculo-cisternal perfusion is not necessary in cases of a 10-fold overdose if the patient has no signs of acute neurotoxicity.  相似文献   
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