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To verify the clinical usefulness of extracellular cyclic nucleotide determination as a tumor marker, plasma cyclic AMP (cAMP) and cyclic GMP (cGMP) levels were measured in 70 normal subjects and 173 acute leukemia patients studied in different stages of their disease. Mean plasma cAMP levels were similar in leukemic and normal subjects, although in 48 patients in the active stage of the disease, first diagnosis, or relapse, the cAMP values were below the normal range, and most of these patients failed to respond to chemotherapy. Plasma cGMP levels were markedly elevated in untreated patients, normalized in all patients who attained complete remission, and increased promptly to pretreatment values in patients who relapsed, suggesting that their determination may be useful to monitor the patients' response to treatment.  相似文献   
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AIMS: To test the hypothesis that local injection of the N-methyl-D-aspartate (NMDA) receptor antagonist ketamine would significantly attenuate glutamate-evoked masseter mechanical sensitization and muscle pain in healthy young women either taking oral contraceptives (W+OC) or not taking oral contraceptives (W-OC). METHODS: Experimental pain was evoked in 47 healthy female subjects (W+OC, n=25; W-OC, n=22) by 2 injections of glutamate (0.2 mL, 1 mol/L) into the masseter muscle. A first injection of glutamate alone was followed by a second injection, 35 minutes later, of glutamate combined with ketamine (0, 1, or 10 mmol/L). Evoked pain intensity was scored on a 10-cm electronic visual analog scale (VAS). Distribution of perceived pain was drawn on a lateral view of the face (pain drawing). Masseter muscle pressure pain thresholds (PPT) and pressure-pain tolerances (PPTOL) were determined bilaterally before and at regular time intervals after injections. Analyses of variance (ANOVA) were used to test the data. RESULTS: There were no main effects of ketamine on any of the VAS pain parameters or on the pain drawing (ANOVAs: P > .055). Furthermore, there were no differences in PPT, PPTOL, VAS peak pain, duration, overall VAS pain, or pain drawing when W-OC were compared with W+OC (ANOVAs: P > .087). Repeated injection of glutamate alone significantly decreased PPT and PPTOL (ANOVAs: P < .001); however, this effect was not significantly attenuated by ketamine. CONCLUSIONS: Peripherally administered ketamine had no effect on glutamate-evoked masseter muscle pain and sensitization in healthy young women, which contrasts with recent observations in healthy young men. Further studies will be needed to reveal the mechanisms that underlie this apparent sex-related difference in ketamine-mediated analgesia.  相似文献   
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基于物体空间序法的CT图像三维重建算法的研究   总被引:5,自引:0,他引:5  
首先对三维可视化方法进行了分类概述。接着对基本的物体空间序法及其改进算法——抛雪球法做了详细的描述,并且通过对两组CT数据进行三维重建实验,得到高质量的重构图像。最后,本文研究并采用了提取表面体素进行体绘制加速的方法,实现了基于等值面提取表面的加速算法,实验证明加速算法能够满足显示要求并能起到明显的加速作用。  相似文献   
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The aim of this study was to determine if the following characteristics were associated with the presence of psoriatic arthritis in a sample of psoriasis patients: race, family history of psoriasis and psoriatic arthritis, age of onset of psoriasis, smoking, alcohol consumption and the maximum body surface area (BSA) affected by psoriasis. This was a case–control study involving 400 psoriasis patients who attended the Psoriasis and Photo‐medicine clinic in the National Skin Center of Singapore over a 1‐year period. Cases were psoriasis patients with psoriatic arthritis while controls were psoriasis patients without psoriatic arthritis. The diagnosis of psoriatic arthritis was made by rheumatologists and participants completed a self‐administered standardized questionnaire. The maximum BSA involved was determined from the case notes. Psoriatic arthritis was not significantly associated with sex, race, age of onset of psoriasis, a family history of psoriasis, smoking and alcohol consumption but was significantly associated with a family history of psoriatic arthritis (P < 0.001) and the maximum body surface involved (P = 0.05). Using multivariate analysis to control for variables, the presence of psoriatic arthritis was significantly associated with a family history of psoriatic arthritis (odds ratio [OR] = 20.5; 95% confidence interval [CI] = 2.49–169.10) and the maximum BSA involved (OR = 2.52; 95% CI = 1.33–4.75). Indian psoriatic patients were more likely to have psoriatic arthritis compared to the other races. A family history of psoriatic arthritis and a greater maximum body surface involved may be associated with having psoriatic arthritis in this study population of psoriasis patients.  相似文献   
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We investigated the possibility of distinguishing between primary endometrial and endocervical adenocarcinomas by using a panel of immunohistochemical stains, which included vimentin (VIM), carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA), and cytokeratins 7 and 20 (CK7 and CK20). Twenty-nine endocervical adenocarcinomas (CCAs) and 30 endometrial adenocarcinomas (EMCAs) including cases with overlapping histologic features (CCAs with endometrioid differentiation [15/29] and EMCAs with mucinous differentiation [16/30]) were evaluated. Most EMCAs (29/30, 97%) were VIM positive, whereas only 2/29 (7%) CCAs were VIM positive. The great majority of EMCAs (28/30) and all 29 CCAs were CK7 positive, whereas all 30 EMCAs and 27/29 CCAs were negative for CK20. CEA positivity was more common in CCAs (18/29, 62%) than in EMCAs (8/30, 27%). EMA positivity was present in all 30 EMCAs and in 26 of 29 (90%) CCAs. We conclude that VIM and CEA are useful immunohistochemical markers in distinguishing EMCAs and CCAs, but CK7, CK20, and EMA are not useful in this distinction.  相似文献   
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