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排序方式: 共有1017条查询结果,搜索用时 15 毫秒
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Postoperative nomogram predicting the 10-year probability of prostate cancer recurrence after radical prostatectomy. 总被引:3,自引:0,他引:3
Andrew J Stephenson Peter T Scardino James A Eastham Fernando J Bianco Zohar A Dotan Christopher J DiBlasio Alwyn Reuther Eric A Klein Michael W Kattan 《Journal of clinical oncology》2005,23(28):7005-7012
PURPOSE: A postoperative nomogram for prostate cancer recurrence after radical prostatectomy (RP) has been independently validated as accurate and discriminating. We have updated the nomogram by extending the predictions to 10 years after RP and have enabled the nomogram predictions to be adjusted for the disease-free interval that a patient has maintained after RP. METHODS: Cox regression analysis was used to model the clinical information for 1,881 patients who underwent RP for clinically-localized prostate cancer by two high-volume surgeons. The model was externally validated separately on two independent cohorts of 1,782 patients and 1,357 patients, respectively. Disease progression was defined as a rising prostate-specific antigen (PSA) level, clinical progression, radiotherapy more than 12 months postoperatively, or initiation of systemic therapy. RESULTS: The 10-year progression-free probability for the modeling set was 79% (95% CI, 75% to 82%). Significant variables in the multivariable model included PSA (P = .002), primary (P < .0001) and secondary Gleason grade (P = .0006), extracapsular extension (P < .0001), positive surgical margins (P = .028), seminal vesicle invasion (P < .0001), lymph node involvement (P = .030), treatment year (P = .008), and adjuvant radiotherapy (P = .046). The concordance index of the nomogram when applied to the independent validation sets was 0.81 and 0.79. CONCLUSION: We have developed and validated as a robust predictive model an enhanced postoperative nomogram for prostate cancer recurrence after RP. Unique to predictive models, the nomogram predictions can be adjusted for the disease-free interval that a patient has achieved after RP. 相似文献
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Is 18F-FDG PET/CT useful for imaging and management of patients with suspected occult recurrence of cancer? 总被引:5,自引:0,他引:5
Ora Israel Maya Mor Luda Guralnik Nirit Hermoni Diana Gaitini Rachel Bar-Shalom Zohar Keidar Ron Epelbaum 《Journal of nuclear medicine》2004,45(12):2045-2051
Rising serum tumor markers may be associated with negative imaging in the presence of cancer. CT and (18)F-FDG PET may yield incongruent results in the assessment of tumor recurrence. The present study evaluates the incremental role of (18)F-FDG PET/CT for the diagnosis and management of cancer patients with increasing levels of tumor markers as the sole indicator of potential recurrence after initial successful treatment. METHODS: Thirty-six cancer patients with increasing levels of tumor markers during follow-up and negative CT underwent (18)F-FDG PET/CT, which showed 111 sites of increased tracer uptake. PET/CT was compared with PET results on a site-based analysis for characterization of (18)F-FDG foci and on a patient-based analysis for diagnosis of recurrence. The clinical impact of PET/CT on further patient management was evaluated. RESULTS: Thirty patients (83%) had recurrence in 85 malignant sites (77%). For the site-based analysis, PET had a sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of 96%, 50%, 85%, 85%, and 82%, respectively, as compared with the performance indices of PET/CT of 100%, 89%, 97%, 97%, and 100%, respectively. There was a statistically significant difference between the specificity (P < 0.05) and accuracy (P < 0.001) of PET and PET/CT for precise characterization of suspected lesions. For the patient-based analysis, PET had a sensitivity, specificity, and accuracy of 93%, 50%, and 86%, respectively, as compared with PET/CT with values of 93%, 67%, and 89%, respectively (P = not significant). PET/CT was the single modality that directed further management and treatment planning in 12 patients (33%). CONCLUSION: The results of this study indicate that PET/CT may improve the accuracy of occult cancer detection and further lead to management changes in patients with increasing levels of tumor markers as the sole suspicion of recurrent malignancy. 相似文献
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In vitro potencies of native and modified forms of salmon and mammalian gonadotropin-releasing hormone (GnRH) were studied in relation with their susceptibility to degradation by intact pituitary cells maintained in culture. The kinetics of degradation and the origin of the proteases involved in this process were examined. All the molecules tested (native and modified forms) were equipotent at doses between 10(-6) and 10(-7) M in inducing GtH release by cultured pituitary cells. On the other hand, their effectiveness differed at 10(-9) and 10(-8) M leading to the establishment of the following hierarchy of bioactivity: the native forms, LHRH and sGnRH, were the less potent, the fish analogues (DAla6Pro9Net)sGnRH and (DArg6Pro9Net)sGnRH were the more potent, and mammalian analogues with substitutions at position 6 and/or 10 were intermediate in potency. The native form sGnRH was weakly degraded while no degradation of the modified molecules was observed. The degradation of the native sGnRH occurred after 12 and 24 hr of incubation and the results indicate that the peptidases involved are released from the cells into the incubation medium. 相似文献
6.
Hagit Cohen Joseph Zohar Michael A Matar Zeev Kaplan Amir B Geva 《Neuropsychopharmacology》2005,58(8):640-650
BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies. 相似文献
7.
Despite the wide clinical use of lithium in the treatment of manic depressive illness there is no adequate explanation for its mechanism of action. In the light of lithium's suggestive effects on the second messenger system in the brain, we studied the effects of chronic dietary lithium treatment (achieving blood levels in the therapeutic range) on protein phosphorylation in different areas of rat brain. An increase in the phosphorylation of a 64-kDa membrane-associated protein was evident in the lithium-treated rats compared to controls. This increase was observed only under basal phosphorylating conditions and was abolished when the phosphorylation was performed in the presence of Ca2+ or Ca2+ and calmodulin. The possibility that this 64-kDa protein affected by lithium is the beta-subunit of the calmodulin-dependent protein kinase or a different protein which co-migrates with it is discussed. 相似文献
8.
Anderson LV Davison K Moss JA Young C Cullen MJ Walsh J Johnson MA Bashir R Britton S Keers S Argov Z Mahjneh I Fougerousse F Beckmann JS Bushby KM 《Human molecular genetics》1999,8(5):855-861
Recently, a single gene, DYSF, has been identified which is mutated in patients with limb-girdle muscular dystrophy type 2B (LGMD2B) and with Miyoshi myopathy (MM). This is of interest because these diseases have been considered as two distinct clinical conditions since different muscle groups are the initial targets. Dysferlin, the protein product of the gene, is a novel molecule without homology to any known mammalian protein. We have now raised a monoclonal antibody to dysferlin and report on the expression of this new protein: immunolabelling with the antibody (designated NCL-hamlet) demonstrated a polypeptide of approximately 230 kDa on western blots of skeletal muscle, with localization to the muscle fibre membrane by microscopy at both the light and electron microscopic level. A specific loss of dysferlin labelling was observed in patients with mutations in the LGMD2B/MM gene. Furthermore, patients with two different frameshifting mutations demonstrated very low levels of immunoreactive protein in a manner reminiscent of the dystrophin expressed in many Duchenne patients. Analysis of human fetal tissue showed that dysferlin was expressed at the earliest stages of development examined, at Carnegie stage 15 or 16 (embryonic age 5-6 weeks). Dysferlin is present, therefore, at a time when the limbs start to show regional differentiation. Lack of dysferlin at this critical time may contribute to the pattern of muscle involvement that develops later, with the onset of a muscular dystrophy primarily affecting proximal or distal muscles. 相似文献
9.
Analysis of consecutive emergency referrals to a community mental hospital over a 2-month period indicates that admissions are affected by a combination of demographic, clinical, and time factors. Both referrals and admissions were slightly higher in men. The mean age at referral was 44 years and of admitted patients was 30 years. Although married subjects constituted the largest group of applicants, widowers and divorced people were hospitalized more often. Both referral and admission rates were inversely correlated with education and employment. Most of the applicants came to the emergency ward accompanied by an escort. A lower rate of admissions was observed among those who came unescorted. The main indications for admission were acute psychosis and a nonspecific clinical state when the patient was defined as "dangerous to himself or to others." The family constituted the main source of referral. Peak referrals were during the morning hours, but admission rates were highest at night. Referrals decreased gradually from Sunday to Saturday, but the rate of admission was practically steady throughout the week. We conclude that the decisions for admitting a patient to a mental institute are based not only on pure psychiatric criteria, but also on an intuitive approach, in which the admitting physician's personal and emotional factors may play a role. 相似文献
10.
Muscle energy metabolism in human phosphofructokinase deficiency as recorded by 31P nuclear magnetic resonance spectroscopy 总被引:3,自引:0,他引:3
31P nuclear magnetic resonance studies of a patient with phosphofructokinase deficiency in muscle provided the following new findings: First, ATP metabolism is disturbed at rest and during exercise. At rest, ATP levels are lower than normal and continue to decline during exercise. Second, exercise kinetics are normal, suggesting a normal mitochondrial fuel supply although glycolysis is blocked. Third, no "phosphate trapping" is observed during prolonged low-level exercise. Fourth, postexercise recovery is abnormally prolonged by the slow dephosphorylation of sugar phosphates, which has an in vivo half-life of about nine minutes. These findings demonstrate how muscle tissue adapts to a block in a major bioenergetic pathway. 相似文献