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11.
Lower limb ulcers present a common clinical problem and are at risk of malignant change. A Marjolin's ulcer has traditionally been regarded as malignant change in a long standing ulcer and/or scar tissue.We report a case of Marjolin's degeneration that developed in an ulcer only 18 months following the initial injury. Such a short latent period has not been reported for over 70 years. This report highlights the possibility of early Marjolin's change and we propose a ranked diagnostic screen to aid in early identification of possible malignant change, based on the current published evidence.  相似文献   
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38 cases of sarcoma of head and neck region were analysed in a retrospective way in relation to age, anatomic location, histological, clinical profile, and surgical approaches. Compared to other types of head and neck neoplasms, such as squamous cell carcinoma, soft tissue sarcomas have low rates of regional metastases. However the biological behaviour of soft tissue sarcoma is more aggressive specially in paediatric age group. In the present series, CT scan was considered as the primary modality of investigation. Surgery generally has been recommended as the primary method of treatment for achieving local control, except in those high-grade tumours arising in sites not amenable to resection. 3-year and 5-year survival rates in this present series 50% and 31.6% respectively.  相似文献   
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The dbl oncogene was initially isolated from a human diffuse B-cell lymphoma. Antisera from mice bearing tumors induced by this oncogene specifically detected a protein of about 66 kDa (p66) in dbl transformants. dbl cDNA-selected poly(A)+ RNA isolated from a transfectant clone expressing p66 directed the in vitro synthesis of this protein, establishing that it is encoded by dbl. Subcellular localization studies revealed that p66 is a cytoplasmic protein distributed between cytosol and crude membrane fractions. Moreover, p66 was shown to be a phosphoprotein, with phosphorylation specific to serine residues. Our characterization of the dbl-encoded protein appears to distinguish this transforming gene product from those of other known oncogenes.  相似文献   
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Sixteen new compounds 2-methylamino substituted phenyl-3-substituted anilino 4 (3H) quinazolinones (3-18) were prepared. All the compounds were evaluated for their antiparkinsonian activity and compared with bromocriptine. Compounds 10,15 and 18 showed better activity. These compounds also bind with the dopamine receptors in striatal membrane preparations of rat brain.  相似文献   
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This study aimed to determine the effects of anti-CD154 on T cell cytokine profiles and ocular chemokine gene expression after high-risk corneal transplantation and to specifically determine if CD154 blockade is associated with a switch from a Th1 to a Th2 alloimmune response. Mice were used as recipients of syngeneic or multiple minor H or MHC antigen-mismatched corneal grafts. Recipient beds were neovascularized (high-risk). Hosts were randomized to receive either anti-CD154 antibody or control immunoglobulin (Ig) perioperatively. Two weeks after corneal transplantation, allospecific delayed-type hypersensitivity (DTH) was evaluated. Frequencies of interferon-gamma (IFN-gamma)-, interleukin-2 (IL-2)-, IL-4-, and IL-5-secreting T cells in the hosts were measured by enzyme-linked immunospot (ELISPOT) assay. Ocular chemokine gene expression in anti-CD154-treated and control hamster Ig-treated groups was determined using a multiprobe ribonuclease protection assay (RPA). Leukocyte infiltration of corneal grafts was evaluated microscopically. Anti-CD154-treated mice did not exhibit allospecific DTH. The frequencies of Th1 cytokine-producing but not Th2 cytokine-producing T cells were significantly reduced in anti-CD154-treated hosts. Postoperative mRNA levels of RANTES and macrophage inflammatory protein-1beta (MIP-1beta) in anti-CD154-treated eyes were substantially suppressed compared with hamster Ig-treated controls. Leukocyte infiltration was profoundly suppressed in grafts of anti-CD154-treated hosts. These data demonstrate that blockade of the CD40-CD154 costimulatory pathway after corneal transplantation inhibits Th1-mediated responses but does not induce a switch to a Th2-specific response. In addition, anti-CD154 therapy suppresses ocular chemokine gene expression and leukocytic infiltration into allografts.  相似文献   
17.
One hundred and five patients with discrete breast lumps were examined with a 10 MHz Doppler ultrasonic flowmeter. Doppler flow signals were analysed on an Angioscan spectrum analyser. Recordings from the opposite normal breast were taken as controls and signals from the two sides compared. In 23 patients signals from the normal breast could not be recorded and therefore results of the remaining 82 patients are reported. These included 39 patients with carcinoma, 20 with fibroadenoma, 12 with cyclical nodularity and 11 with cysts. Malignant lumps exhibited significantly higher peak systolic (S) and minimum diastolic frequencies (D) in comparison to the control breast. Fibroadenoma also had a higher S and D than those of the opposite normal breast. Signals over cysts and cyclical nodularity showed no significant difference from the recordings over the control side. Despite significantly higher systolic and diastolic frequencies in the cancer group in comparison to benign lumps and normal breast, considerable overlap in the values was seen between cancer and other groups. Therefore the patterns on 10 MHz Doppler sonography are not sufficiently specific to discriminate benign from malignant breast lumps.  相似文献   
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