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21.
The first recorded case of lymphoma of the bladder was reported by Eve and Chaffey in 1885. Malignant lymphoma of the bladder can be classified into one of three different clinical groups: 1) Primary lymphoma localized to the bladder; 2) Lymphoma presenting in the bladder as the first sign of disseminated disease (non-localized lymphoma); 3) Recurrent bladder involvement by lymphoma in patients with a history of malignant lymphoma (secondary lymphoma). Primary extranodal marginal zone lymphoma of mucosa associated lymphoid tissue (MALT type) of the urinary bladder, first described by Kempton et al in 1990, is the most common primary bladder lymphoma and associated with an excellent prognosis. We present a patient with gross hematuria who was found to have a primary bladder lymphoma and review the relevant literature.  相似文献   
22.
Retained metal fragments frequently are visualized in x-ray examinations of wounded combat veterans. Retained projectiles (bullets) are seen less often because of surgical removal.  相似文献   
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Detectability of breast cancer with magnetic resonance (MR) imaging versus xeromammography was quantitatively compared. MR images were obtained of breasts of 120 women who underwent xeromammography. T1 values were determined for masses larger than 2 cm. Cancer was histologically confirmed in 39 breasts and was considered excluded from 81 due to results of biopsy, cyst aspiration, or sonography or absence of change in xeromammographic findings over time. Images were blindly interpreted by three observers, and results were expressed as receiver operating characteristic curves. Detectability of breast cancer was substantially better with xeromammography than with MR imaging for all observers (P less than .03, 10(-6), and .001). On MR images, spiculation of a mass, distorted architecture, skin thickening, and nipple or skin retraction were specific but relatively insensitive indicators of cancer. Masses with smooth, distinct margins and signal intensity greater than that of fat on T2-weighted images were always benign. Other findings and T1 values were not diagnostically useful. The authors conclude that xeromammography is superior to MR imaging in detection of breast cancer.  相似文献   
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BACKGROUND: The overexpression of eukaryotic initiation factor 4E (eIF4E), which is a critical component of the RNA helicase complex important in the translation of messenger RNAs with long and/or complex 5' untranslated regions, appears to impact malignant transformation and predict cancer recurrence in patients with breast cancer, independent of nodal status. Tousled-like kinase (TLK1B) is a mammalian threonine kinase with a long 5' untranslated regions in the messenger RNA. In vitro, malignant cells with eIF4E overexpression appear to have corresponding TLK1B elevation. Additionally TLK1B phosphorylates histone 3, which is a protein that is involved in chromatin assembly, plays an integral role in radioresistance in cell lines. Our hypothesis is that patients with breast cancer with high eIF4E overexpression have increased TLK1B and a higher risk for recurrence after adjuvant radiation therapy. METHODS: One hundred fifty-eight patients with stage I to III breast cancer were accrued in a prospective study that was designed to detect cancer recurrence in patients who had been treated with adjuvant radiation therapy. A standardized surveillance and treatment protocol was used to maximize treatment homogeneity and to detect the study primary end point, cancer recurrence. All patients received adjuvant radiation therapy either for high-risk node-positive disease or as a part of breast conservation therapy. TLK1B and eIF4E levels were quantified by Western blot. Statistical analysis was performed and included Spearman correlation, survival analysis by the Kaplan-Meier method, log-rank test, and Cox proportional hazard model. RESULTS: Both eIF4E (15.4 +/- 0.6, mean +/- SD) and TLK1B (18.8 +/- 1.5) were increased in all breast cancer specimens. Increasing eIF4E overexpression was correlated highly with increasing TLK1B (r = 0.35; P < .0001, Spearman coefficient). Tertile distribution of patients, based on the degree of eIF4E and TLK1B increase, demonstrated that the patients in the highest eIF4E group and the highest TLK1B group had a higher rate of cancer recurrences (P = .015 and .049, log rank test, respectively). After adjustment for stage of disease, age, and estrogen/progesterone receptor status, data showed that patients in the highest TLK1B group had a 3.0-fold increase in relative risk for cancer recurrence after adjuvant radiation therapy (P = .036; 95% CI, 1.0-5.0), compared with patients in the low TLK1B group. CONCLUSION: The overexpression of eIF4E is correlated with TLK1B increase in cancer specimens from patients with stage I to III breast cancer. High TLK1B increase in tumor specimens was associated with a higher risk for cancer recurrence after adjuvant radiation therapy. Resistance to radiotherapy may be 1 mechanism whereby eIF4E overexpression in breast cancer portends a worse prognosis.  相似文献   
27.
赤芝子实体中灵芝酸类成分的研究   总被引:15,自引:1,他引:15  
自赤芝[Ganodermalucidum(Fr.)Karst.]子实体的二氯甲烷提取物中分离得到一个新的四环三萜化合物,命名为灵芝酸DM(ganodericacidDM,I)。根据光谱(UV,IR,1HNMR,13CNMR,MS2DNMR)分析,确定其结构为I式。同时还分离得到二个已知的灵芝酸类化合物,即灵芝酸A(ganodericacidA,I)和灵芝酸C(ganodericacidC,II)。  相似文献   
28.
N-methyl-D-aspartate (NMDA) receptors are known to fulfill crucial functions in many forms of learning and plasticity. More recently, biophysical models, however, have suggested an additional role of NMDA receptors in evidence integration for decision-making, going beyond their role in learning. We designed a task to study the role of NMDA receptors in human reward-guided learning and decision-making. Human participants were assigned to receive either 250 mg of the partial NMDA agonist d-cycloserine (n=20) or matching placebo capsules (n=27). Reward-guided learning and decision-making were assessed using a task in which participants had to integrate learnt and explicitly shown value information to maximize their monetary wins and minimize their losses. To tease apart the effects of NMDA on learning and decision-making we used simple learning models. D-cycloserine shifted decision-making towards a more optimal integration of the learnt and the explicitly shown information, in the absence of a direct learning effect. In conclusion, our results reveal a distinct role for NMDA receptors in reward-guided decision-making. We discuss these findings in the context of NMDA''s roles in neuronal super-additivity and as crucial for evidence integration for decisions.  相似文献   
29.
乏氧细胞对射线所具有的较大抗性是对某些人类肿瘤进行放疗失效的主要原因。放射增敏剂的研究目的是为了提高射线在正常组织可耐受剂量下对肿瘤细胞的杀伤率,从而提高放疗效果。目前试用于临床的放射增散剂misoniizole(MISO)是一种硝基咪唑类化合物,由于其较强的神经毒性,限制了这种药物的推广和使用。为寻找新的低毒有效的放射增敏剂,我们设计并合成了一系列化合物,试验了它们对离体Hela-S_3细胞的放射增敏作用。  相似文献   
30.
Thirteen new 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-aroyl-thiocarbamoyl- 1 piperazinyl)-3-quinoline carboxylic acids were prepared, Their structures were characterized by elemental analysis, IR, HNMR and MS spectra.Preliminary pharmacological tests indicated that some of compounds Ia~m possess strong inhibiting activity against Escherichia coli, Bacillus subtilis and Proteus at concentration of 100 μg/ml.  相似文献   
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