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51.
52.
PurposeWe evaluated the prognostic value of 10 putative tumor markers by immunohistochemistry in a large multi-institutional cohort of patients with locally advanced urothelial cancer of the bladder (UCB) with the aim to validate their clinical value and to harmonize protocols for their evaluation.Materials and MethodsPrimary tumor specimens from 576 patients with pathologic (p)T3 UCB were collected from 24 institutions in North America and Europe. Three replicate 0.6-mm core diameter samples were collected for the construction of a tissue microarray (TMA). Immunohistochemistry (IHC) for 10 previously described tumor markers was performed and scored at 3 laboratories independently according to a standardized protocol. Associations between marker positivity and freedom from recurrence (FFR) or overall survival (OS) were analyzed separately for each individual laboratory using Cox regression analysis.ResultsThe overall agreement of the IHC scoring among laboratories was poor. Correlation among the 3 laboratories varied across the 10 markers. There was generally a lack of association between the individual markers and FFR or OS. The number of altered cell cycle regulators (p53, Rb, and p21) was associated with increased risk of cancer recurrence (P < 0.032). There was no clear pattern in the relationship between the percentage of markers altered in an 8-marker panel and FFR or OS.ConclusionsThis large international TMA of locally advanced (pT3) UCB suggests that altered expression of p53, Rb, and p21 is associated with worse outcome. However this study also highlights limitations in the reproducibility of IHC even in the most expert hands.  相似文献   
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Exposing individuals to an isolated component (a prime) of a prior event alleviates its forgetting. Two experiments with 120 human infants between 3 and 18 months of age determined the minimum duration of a prime that can reactivate a forgotten memory and how long the reactivated memory persists. Infants learned an operant task, forgot it, were exposed to the prime, and later were tested for renewed retention. In Experiment 1, the minimum duration of an effective prime decreased logarithmically with age, but was always longer than the duration of a mere glance. In Experiment 2, the reactivated memory was forgotten twice as fast after a minimum-duration prime as after a full-length one, irrespective of priming delay and infant age. These data reveal that the minimum effective prime duration psychophysically equates the accessibility of forgotten memories. We conclude that priming is perceptually based with effects that are organized on a ratio (log) scale.  相似文献   
55.
To determine the effect of ileal oleate on fasting intestinal motility, pairs of duodenal and ileal catheters and bipolar duodenal and jejunal seromuscular electrodes were surgically implanted in six dogs. The ileum was perfused with either normal saline (154 mM NaCl) or oleic acid emulsion (152 mM), while intestinal myoelectric activity was continuously monitored. For transit studies, a bolus of [3H]PEG was injected into the duodenum, and jejunal and ileal alliquots were collected every 15 min for a 6-hr study period. Plasma samples were collected for radioimmunoassays of peptide YY and enteroglucagon. Ileal oleate infusion increased the MMC cycle length and decreased the number of MMCs (P<0.001) and the myoelectric spike-burst frequency/10 min in the duodenum (P<0.05). Both duodenal-jejunal (P<0.05) and duodenal-ileal transit (P<0.01) were delayed markedly by ileal perfusion with oleic acid emulsion as compared to control studies. Ileal oleate increased plasma levels of peptide YY (P<0.01) and enteroglucagon (P<0.01). Ileal perfusion with oleate therefore activated the so-called ileal brake, diminishing duodenal myoelectric spike bursts and slowing intestinal transit while concurrently increasing plasma levels of peptide YY and enteroglucagon.Dr. Dreznik is currently at Tel Aviv University, Tel Aviv, Israel, at the Sackler Faculty of Medicine.An abstract of this work was presented at the Forum of Fundamental Problems at the American College of Surgeons meeting in October 1991.Supported by the V.A. Research Advisory Group, NIH Biomedical Research Support Grant.  相似文献   
56.
Triciribine is a purine analogue which inhibits DNA and protein synthesis. We performed two studies to define its activity against metastatic breast cancer. The first study was a phase II study in 14 patients with metastatic breast cancer who had received two or fewer chemotherapy treatments. The treatment schedule was triciribine 20 mg/m2 per day by 24-h infusion (CI) daily for 5 days every 6 weeks as recommended by a previous open phase I trial. When neither response nor toxicity was seen in the phase II trial, we assumed the starting dose was too low for this group of patients with good performance status and repeated the phase I trial in patients with metastatic breast cancer with good performance status. The starting dose was 35 mg/m2 per day using the same 5-day CI schedule, and starting doses were increased in subsequent cohorts of three patients in increments of 5 mg/m2 until toxicity occurred. In the initial (phase II) study, one patient had stable disease for 18 weeks (three courses), the remainder progressed. There were no significant toxic effects. In the subsequent phase I study, ten patients were treated until the study was closed The maximum dose was 40 mg/m2. Two patients died, one each at the 35 and 40 mg/m2 levels, respectively, 3 months and 6 weeks after their last course, one without interveing disease progression. Both had severe hypertriglyceridemia (18- and 21-fold elevation) and severe fatigue. At postmortem examination, one had congestive cardiomyopathy, and the other had severe pancreatitis and hypothyroidism. One patient had severe exacerbation of psoriasis which made her bedridden for more than 30 days. Four patients had hyperglycemia. Plasma pharmacology studies showed erratic drug levels, presumably related to enterohepatic circulation. Postmortem pharmacology studies showed residual drug present as long as 12 weeks after the last dose. We conclude that triciribine is ineffective at all doses tested and at doses of 35 mg/m2 has unacceptable toxic effects.This work was performed under National Cancer Institute contract 1-CM-57739  相似文献   
57.
OBJECTIVE: To evaluate, in compliant patients, the pharmaceutical costs of treating obesity with fenfluramine/mazindol, fenfluramine/phentermine, caffeine/ephedrine, or mazindol relative to the pharmaceutical costs of treating obesity-related comorbid conditions and reducing cardiovascular risk. METHODS AND PROCEDURES: Subjects were between 18 and 60 years of age with a BMI of >30 kg/m2. Pharmaceutical costs were evaluated in 73 of 220 subjects taking medications for diabetes, hyperlipidemia, or hypertension before and after treatment using fenfluramine with mazindol or phentermine. The pharmaceutical cost of weight loss, cardiac risk reduction, and low-density lipoprotein (LDL) cholesterol reduction was calculated for fenfluramine with mazindol or phentermine, caffeine with ephedrine, or mazindol alone, and compared to approved lipid-lowering medications. RESULTS: Losses of 6% to 10% of initial body weight reduced pharmacy costs $122.64/month for insulin treated diabetes, $42.92/month for sulfonylurea-treated diabetes, $61.07/month for hyperlipidemia treated with medication, and $0.20/month for hypertension treated with medication. Blood pressure and laboratory evidence of insulin resistance improved in all medication groups. Caffeine/ephedrine was most cost-effective of the three treatments in reducing weight, cardiac risk, and LDL cholesterol. DISCUSSION: Obesity medications produced a substantial weight loss in compliant patients and resulted in a net pharmaceutical cost savings compared to treating obesity related comorbid conditions.  相似文献   
58.
In order to predict kidney graft survival, the influence of independent prognostic factors can be examined multivariately and the factors combined into a prognostic index. Data on 7121 patients receiving an unrelated first and 1033 patients receiving an unrelated second transplant from nonliving donors, between 1 January 1984 and 31 December 1987, were analyzed to ascertain the most important prognostic variables up to 4.5 years posttransplantation. Factors found to be significant for graft survival were donor and recipient age and sex, recipient blood group, whether the recipient was diabetic, cold ischemic period, number of HLA-B and - DR mismatches, highest percent panel-reactive antibody, transplant center, and--for second transplants--duration of first graft. A risk score for graft failure, based on the prognostic factors, was developed using these factors and five risk groups (from excellent to very poor prognosis) were identified. This index was tested on an independent data set and showed a good fit when compared with the observed Kaplan-Meier graft survival: patients allocated by the risk score into the "excellent prognosis" group had an observed one-year graft survival of 90.4%, compared with a predicted value of 90.3% for first transplants. Corresponding results for second transplants were 86.2% (observed) and 86.0% (predicted). For the "very poor" prognosis group, the results were 73.4% (observed) and 74.4% (predicted), for first transplants, and 60.9% (observed) and 60.1% (predicted), for second transplants. A prognostic index can therefore identify patients likely to have a high or low graft survival, leading to improved decision-making and aiding the choice of patient management once a recipient has been transplanted.  相似文献   
59.
Summary Thirty-four patients were treated with N-(phosphonacetyl)-l-aspartate (PALA) at a dose of 850 mg/m2/dayx5 by continuous intravenous infusion (days 1–5) and 5-fluorouracil (5-FU) on an escalating dose schedule of 300–630 mg/m2/dayx5 by continuous intravenous infusion (days 2–6). Dose-limiting oral mucositis occurred at a 5-FU dose of 560 mg/m2/day; other toxicities included nausea, vomiting, diarrhea, skin rash, and superficial venous phlebitis. Myelosuppression was rare. One partial response was observed in a patient with metastatic colorectal carcinoma. Plasma PALA levels were monitored in seven patients. Steady-state levels were achieved by the 2nd day of drug infusion and ranged between 10 and 20 g/ml.  相似文献   
60.
OBJECTIVE: To determine the relative risk of severe intraventricular hemorrhage (IVH) between two very early indomethacin treatment strategies. STUDY DESIGN: Retrospective chart review of infants <29 weeks gestation and <1350 g who received either indomethacin prophylaxis or very early echocardiography with indomethacin treatment only if the ductus arteriosus was patent. RESULTS: A total of one hundred and two infants received prophylactic indomethacin (pINDO). Echochardiography was performed on 158 infants, of whom 117 received indomethacin. Infants receiving pINDO had lower gestational age, but similar birth weight, gender, race, antenatal steroid exposure, delivery mode, Apgar scores, and need for resuscitation as infants evaluated by echocardiography. Grades III to IV IVH was observed less frequently in infants who received pINDO (OR 0.27, 95% CI 0.10 to 0.77, p=0.014). Frequency of side effects and recurrent patent ductus arteriosus did not differ between treatment groups. CONCLUSION: pINDO reduces severe IVH when compared to an early echocardiography strategy.  相似文献   
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