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61.
62.
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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64.
The pathogenesis of human asthma and the development of key features of pulmonary allergy in mouse models has been critically linked to IL-13. Analyses of the receptor components employed by IL-13 have shown that delivery of this cytokine to the airways of naive IL-4Ralpha gene targeted (IL-4Ralpha(-/-)) mice fails to induce disease, suggesting that this membrane protein is critical for transducing IL-13-mediated responses. The current study demonstrates that, in contrast to naive mice, T helper 2 bias, airways hyperreactivity (AHR) and tissue eosinophilia develop in Ovalbumin-sensitized IL-4Ralpha(-/-) mice and that these responses can be inhibited by the IL-13 antagonist sIL-13Ralpha2Fc. Therefore, antigen stimulation induces an IL-13-regulated response that is independent of IL-4Ralpha. To determine the role of IL-5 and eosinophils in the development of disease in antigen-exposed IL-4Ralpha(-/-) mice, pulmonary allergy was examined in mice deficient in both factors. IL-4Ralpha/IL-5(-/-) mice were significantly defective in their ability to produce IL-13 and failed to develop AHR, suggesting that IL-5 indirectly regulates AHR in allergic IL-4Ralpha(-/-) mice by an IL-13-dependent mechanism. Collectively, these results demonstrate that IL-13-dependent processes regulating the development of AHR and T helper bias persist in the in the lungs of allergic IL-4Ralpha(-/-) mice.  相似文献   
65.
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   
66.
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   
67.
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   
68.

Purpose

Uncertainties remain regarding the clinical efficacy of ovarian tissue cryopreservation and grafting. We report a retrospective analysis of reproductive outcomes and lessons learnt following 55 ovarian tissue transplant procedures at our center from 2006 to 2019.

Methods

We analyzed variables related to graft success such as tissue volume, follicular density, total follicular volume, and age on the duration of graft function.

Results

Follicular density and total follicular volume correlate positively with duration of graft function. All clinical pregnancies in our cohort occurred in women who were aged 35 or less at the time of ovarian tissue cryopreservation.

Conclusion

Graft success, as determined by eventual pregnancy and the longevity of graft function, may be impacted by factors including age at cryopreservation, follicular density, and total follicular volume.
  相似文献   
69.
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   
70.
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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