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71.
PURPOSE: Methyl-[11C]L-methionine ([11C]MET) positron emission tomography (PET) in brain tumors reflects amino acid transport and has been shown to be more sensitive than magnetic resonance imaging in stereotactic biopsy planning. It remains unclear whether the increased [11C]MET uptake is limited to solid tumor tissue or even detects infiltrating tumor parts. EXPERIMENTAL DESIGN: In 30 patients, a primary or recurrent brain tumor was suspected on magnetic resonance imaging. Patients were investigated with [11C]MET-PET before stereotactic biopsy. The biopsy trajectories were plotted into the [11C]MET-PET images with a newly designed C-based software program. The exact local [11C]MET uptake was determined within rectangular regions of interest of 4 mm in width and length aligned with the biopsy specimen. Individual histologic specimens were rated for the presence of solid tumor tissue, infiltration area, and nontumorous tissue changes. RESULTS: Receiver operating characteristics analysis demonstrated a sensitivity of 87% and specificity of 89% for the detection of tumor tissue at a threshold of 1.3-fold [11C]MET uptake relative to normal brain tissue. At this threshold, only 13 of 100 tumor positive specimen were false negative mainly in grade 2 astrocytoma. In grade 2 astrocytoma, mean [11C]MET uptake in the infiltration area was significantly higher than in solid tumor tissue (P < 0.003). CONCLUSIONS: [11C]MET-PET detects solid parts of brain tumors, as well as the infiltration area at high sensitivity and specificity. High [11C]MET uptake in infiltrating tumor of astrocytoma WHO grade 2 reflects high activity in this tumor compartment. Molecular imaging, with [11C]MET, will guide improved management of patients with brain tumors.  相似文献   
72.
73.
BACKGROUND AND PURPOSE: Interstitial implants for brachytherapy boost in the breast conserving therapy of breast cancer can be performed in two ways; implants during the tumor excision (per-operative implants) or after the external beam therapy (delayed interstitial implants). Differences in cosmetic outcome were investigated. PATIENTS AND METHODS: Cosmetic results in 47 patients having a per-operative implant were compared to 123 patients having a delayed interstitial implant in a matched case-control study. Cosmesis was scored on a four-point-scale varying from 0 (excellent) to 3 (poor). RESULTS: After mean follow-up of 63 months, three observers found no difference in cosmetic outcome between the two groups after adjustment for variables found to be related with cosmesis (difference in mean score 0.50, P=0.26). Implant volume at 100% isodose was not found to differ (P=0.084) between the per-operative group (mean 102 cm3, S.D. 34 cm3) and the delayed group (mean 93 cm3, S.D. 29 cm3). CONCLUSIONS: Performing per-operative implants has not led to smaller implants. The method of performing brachytherapy does not result in marked differences in cosmetic outcome.  相似文献   
74.
PURPOSE: With limited response rates and potential toxicity of chemotherapeutic treatment in patients with recurrent glioma, reliable response assessment is essential. Currently, the assessment of treatment response in glioma patients is based on the combination of radiologic and clinical findings. However, response monitoring with computed tomography (CT) or magnetic resonance imaging (MRI) is hampered by several pitfalls and is prone to interobserver variability. The aim of this study was to establish the value of thallium-201 single-photon emission computed tomography (201Tl-SPECT) as a predictor of overall survival and response to chemotherapy in recurrent glioma, and to compare the value of 201Tl-SPECT with that of CT and MRI. PATIENTS AND METHODS: We studied patients who underwent CT or MRI and 201Tl-SPECT before chemotherapy (n = 57), and patients who also had undergone CT or MRI and 201Tl-SPECT after two courses of chemotherapy (n = 44). The value of the radiologic variables (CT-MRI tumor size, 201Tl-SPECT tumor size, and maximal tumor intensity) at baseline and at follow-up in predicting overall survival, and the percentage of patients alive and progression-free at 6 months (APF6) were examined using Cox regression and logistic regression analysis. RESULTS: Both at baseline and at follow-up, 201Tl-SPECT maximal tumor intensity was the strongest predictive variable and was inversely related to overall survival and APF6. In particular, progression of maximal tumor intensity after two courses of chemotherapy was a powerful predictor of poor outcome. CONCLUSION: 201Tl-SPECT is superior to conventional CT-MRI in the early prediction of overall survival and response to chemotherapy in patients with recurrent glioma.  相似文献   
75.
PURPOSE: This phase II clinical study evaluated the efficacy of pemetrexed for the treatment of malignant pleural mesothelioma (MPM). PATIENTS AND METHODS: Patients with a histologically proven diagnosis of MPM, chemotherapy-naive measurable lesions, and adequate organ function received pemetrexed (500 mg/m2) intravenously over 10 minutes every 3 weeks. After a protocol change, most patients also received folic acid and vitamin B12 supplementation to improve safety. RESULTS: A total of 64 patients were enrolled. Nine (14.1%) of the 64 patients had a partial response. The Kaplan-Meier estimate for median overall survival was 10.7 months. Forty-three patients received vitamin supplementation for all courses of therapy, and 21 patients did not. Seven of the nine responders were vitamin supplemented. The median overall survival was 13.0 months for supplemented patients and 8.0 months for nonsupplemented patients. Vitamin-supplemented patients completed more cycles of therapy than nonsupplemented patients (median, six v two cycles, respectively). Grade 3/4 neutropenia (23.4%) and grade 3/4 leukopenia (18.8%) were the most common laboratory toxicities. Fatigue and febrile neutropenia were the most commonly reported nonlaboratory events (grade 3, 6.3%; grade 4, 0.0% each). The incidence of these toxicities was generally lower in the supplemented patients. CONCLUSION: Single-agent pemetrexed for MPM resulted in a moderate response rate (14.1%) and median overall survival of 10.7 months. Patients supplemented with folic acid and vitamin B12 tolerated treatment better (less toxicity and more cycles of treatment) and had a 5-month greater median overall survival than nonsupplemented patients. These results indicate that patients with MPM could benefit from single-agent pemetrexed treatment combined with vitamin supplementation.  相似文献   
76.
Secondary stones, those with no "classic" cause, provide unusual diagnostic and treatment challenges to the urologist. Stones related to medications, to urinary diversions or augmentation, or to presence of foreign bodies within the urinary tract occur rarely. Nevertheless, they represent situations that may be corrected fully by appropriate conservative or procedural therapy, and therefore they must be included in the differential diagnosis of many patients who present with symptoms of urolithiasis.  相似文献   
77.
Glycine receptor channels are pentameric ligand-gated ion channels that respond to the application of inhibitory neurotransmitters by opening of a chloride-selective central pore. Topiramate (TPM) is a broad-spectrum antiepileptic drug used as add-on or monotherapy for focal seizures. In the present study the interaction of TPM with glycine receptor channels was studied on outside-out patches from HEK293 cells expressing alpha1beta glycine receptor channels. The patch clamp techniques combined with ultra fast solution exchange enabled us to investigate the kinetics of receptor channels in presence of TPM. Our study showed no agonistic or potentiating effect for TPM on glycine receptor channels. However, in presence of 1 mM glycine + 1 mM TPM, the desensitization got faster and the peak current amplitude decreased. After the end of glycine + TPM pulses, off-currents occurred, suggestive for a specific channel block mechanism.  相似文献   
78.
Myocardial infarction has great importance for the populations in industrial countries because of the high morbidity and mortality rates. For research of the epidemiological trends in the 1970s and especially in the 1980s, the World Health Organization (WHO) began registering myocardial infarction throughout the world. The most important aspect was the WHO Monitoring of Trends and Determinants of Cardiovascular Diseases (MONICA) project. From 1974 to 1994 and in 1999 in Chemnitz, Germany, data from patients with acute myocardial infarction were collected for the myocardial infarction register. Despite changes in the event rates from year to year, no decrease in the number of myocardial infarctions in the German population aged 25–64 years was detected, contrary to the trend in the Western industrial states in the period from 1984 to 1994. The event rates in men were significantly higher than in women. In 1999, a significant decrease in the event rates in men and women was found. This may be explained by an incomplete registration of patients with myocardial infarction in 1999 because of the change in the structure of the Public Health System. The highest 28-day fatality rates in men were detected in 1989 and 1990. In women with classic myocardial infarction, a decrease in the 28-day fatality rates after 1993 was recorded, reaching lower rates than those of men. Despite methodological problems, the myocardial infarction register can contribute to a comparison of the morbidity, mortality and case fatality rates of myocardial infarction for a longer period.  相似文献   
79.
Depressive patients show deficits in memory functions. However, the underlying mechanisms remain unclear. Experiments with a special emphasis on the link between emotion and cognition appear challenging. The aim of this study is to investigate the influence of the emotional content of words on memory in non-medicated depressive patients (n=11) compared with a control group (n=11) utilizing event-related brain potentials (ERPs). In a continuous word recognition paradigm brain responses to repeated items are characterized by more positive waveforms of ERPs. This recognition effect ('old/new effect') has been shown to be sensitive to parameters relevant for memory processing. For the purpose of this ERP experiment visually presented words were classified into three different categories of emotional content. The ERPs for the correctly detected 'old' (repeated) words showed an increased positivity beginning approximately 250 ms post-stimulus, concurring with a good recognition performance. In addition, old/new effect and behavioral data were sensitive to words' different emotional connotations in the control group. In contrast, the depressive patients performed worse and showed no significant old/new effect. Nevertheless, their recognition performance was also enhanced by the emotional content. Furthermore, a differential effect of the emotional content on frontal ERPs was found between groups. In contrast to the control group, a reduced old/new effect indicates a reduced working memory capacity in the moderately depressed patients. This is suggested to be partially due to changes of the emotion/cognition coupling related to ruminations with preferably negative emotional connotation. However, the emotional content also affects recognition performance in the depressive patients.  相似文献   
80.
The purpose of this article is to examine the prevalence, degree, and natural course of pupillary neuropathy (PANP), cardiovascular autonomic neuropathy (CANP), and sensorimotor neuropathy (SNP) and to study the impact of disease stage and medication on neuropathy in 61 consecutive patients with HIV. PANP, CANP, and SNP were assessed by standardized test procedures. Overall prevalence of PANP, CANP, and SNP were 66%, 15%, and 15%, respectively. The maximal pupillary area (pupillary measure, p<0.0001) and the lying-to-standing ratio (cardiovascular measure, p<0.0001) were abnormal as compared with control subjects. The changes in CD4+ T-lymphocytes and respiratory sinus arrhythmia percentile during 2 years of follow-up correlated significantly (r=0.758, p=0.007). Patients with CANP were more often in an advanced disease stage than patients without CANP (p=0.004). SNP, but not PANP or CANP, was associated with the intake of the neuropathogenic drugs dideoxycytidine, dideoxyinosine, and 2,3 didehydro-2,3 dideoxythymidine (p<0.05). Autonomic and sensorimotor neuropathy are frequent in patients with HIV, and progression of CANP may put patients at risk for unexpected cardiorespiratory arrest.  相似文献   
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