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11.
Phospho-akt expression is associated with a favorable outcome in non-small cell lung cancer. 总被引:3,自引:0,他引:3
Amit Shah William A Swain Donna Richardson John Edwards Duncan J Stewart Catherine M Richardson Daniel E B Swinson Dipika Patel J Louise Jones Kenneth J O'Byrne 《Clinical cancer research》2005,11(8):2930-2936
Akt, a Serine/Threonine protein kinase, mediates growth factor-associated cell survival. Constitutive activation of Akt (phosphorylated Akt, P-Akt) has been observed in several human cancers, including lung cancer and may be associated with poor prognosis and chemotherapy and radiotherapy resistance. The clinical relevance of P-Akt in non-small cell lung cancer (NSCLC) is not well described. In the present study, we examined 82 surgically resected snap-frozen and paraffin-embedded stage I to IIIA NSCLC samples for P-Akt and Akt by Western blotting and for P-Akt by immunohistochemistry. P-Akt protein levels above the median, measured using reproducible semiquantitative band densitometry, correlated with a favorable outcome (P = 0.007). Multivariate analysis identified P-Akt as a significant independent favorable prognostic factor (P = 0.004). Although associated with a favorable prognosis, high P-Akt levels correlated with high tumor grade (P = 0.02). Adenocarcinomas were associated with low P-Akt levels (P = 0.039). Akt was not associated with either outcome or clinicopathologic variables.Cytoplasmic (CP-Akt) and nuclear (NP-Akt) P-Akt tumor cell staining was detected in 96% and 42% of cases, respectively. Both CP-Akt and NP-Akt correlated with well-differentiated tumors (P = 0.008 and 0.017, respectively). NP-Akt also correlated with nodal metastases (P = 0.022) and squamous histology (P = 0.037).These results suggest P-Akt expression is a favorable prognostic factor in NSCLC. Immunolocalization of P-Akt, however, may be relevant as NP-Akt was associated with nodal metastases, a known poor prognostic feature in this disease. P-Akt may be a potential novel therapeutic target for the management of NSCLC. 相似文献
12.
The cases of 33 children with hypothalamic-chiasmatic gliomas are reviewed. Radiation therapy produced clinical or radiographic improvement in 11 (46%) of 24 patients. Progression was documented in 18 patients (54%). Overall, the median time to tumor progression was 60 months; it was 70 months in patients who received radiation therapy and 30 months in those who did not (P less than 0.05). Chemotherapy, either given initially or at the time of progression, caused the tumor to respond or to stabilize in 10 patients. Partial resection of the tumor led to improvement in 3 of 12 patients, obviating the need for a shunt in 2 of them; there were no deaths and postoperative morbidity was transient and minimal (diabetes insipidus, intraventricular hemorrhage, and left hemiparesis in one patient each). The 5- and 10-year survival probabilities were 93 and 74%, respectively. Patients with neurofibromatosis had a better prognosis. 相似文献
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Aspirin (1 mM), a selective cyclooxygenase inhibitor, decreased endplate potential (e.p.p.) amplitude but did not affect either the biphasic changes in m.e.p.p. frequency or triphasic changes in e.p.p. amplitude induced by crotoxin. Nordihydroguaiaretic acid (30 microM), a dual inhibitor of cyclooxygenase and lipoxygenase pathways, increased e.p.p. amplitude but did not affect the characteristic changes in m.e.p.p. frequency and e.p.p. amplitude in response to crotoxin. The incidence of giant m.e.p.p.s was reduced by aspirin and increased by NDGA. Arachidonate metabolism is not a major factor in the induction of neurotoxicity by crotoxin at the frog neuromuscular junction. 相似文献
15.
Symptomatic and Clinical Improvement in Morbidly Obese Patients with Gastroesophageal Reflux Disease Following Roux-en-Y Gastric Bypass 总被引:3,自引:0,他引:3
Background: Patients who suffer with gastroesophageal reflux Disease (GERD) endure a worsening of symptoms as their weight
increases. When medical treatment of this condition in the morbidly obese patients fails, surgical intervention may be indicated.
Choosing a procedure which not only helps achieve weight control but which also relieves symptoms and complications of GERD
is the goal. We present a review of patients who have undergone Roux-en-Y Gastric Bypass (RYGBP) and related procedures for
this disease. Methods: One hundred eighty-eight patients undergoing surgery for morbid obesity and for GERD in 1992-1996 were
contacted by mail or phone. All of these patients had undergone preoperative esophagogastroduodenoscopy to grade the severity
of their disease. Their preoperative symptoms were compared to those experienced postoperatively. Results: One hundred thirty
patients underwent a RYGBP with modified Hill fundopexy, 22 patients underwent a distal gastrectomy with modified Hill fundopexy,
8 patients underwent distal gastrectomy alone and 28 patients underwent RYGBP alone. There have been no deaths. There were
nine surgical complications, eight early and one at 2.5 years postoperation. Follow-up is 4-48 months. The average BMI dropped
from 43 to 30.2 kg/m2. Whereas all patients were on some form of medical therapy before surgery, only 14 reported the need for medication postoperatively.
Conclusions: Surgical intervention for weight control and treatment of GERD has been highly successful in our experience both
with respect to weight control and to the reduction of reflux symptoms. Depending upon endoscopic and operative findings a
RYGBP with or without an antireflux procedure can provide dramatic improvement. Gastrectomy with antireflux modifications
is appropriate in selected cases. 相似文献
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K. Bischoff J. Pichner W. E. Braselton C. Counard D. C. Evers W. C. Edwards 《Archives of environmental contamination and toxicology》2002,42(1):71-76
Mercury and selenium act as mutual antagonists in mature birds, but their toxicity is additive or synergistic in avian embryos
and immature birds. Twenty eggs and livers from 18 mature and 9 immature common loon carcasses found in Minnesota were collected.
Livers and eggs were analyzed for mercury and selenium by atomic emission and atomic absorption spectroscopy. Liver mercury
concentrations were significantly higher in mature loons compared to those of immature loons and eggs. Liver selenium concentrations
were significantly higher in mature loons than those of immature loons, and selenium concentrations in immature loon livers
were significantly higher than levels in eggs. There was a significant positive correlation between mercury and selenium in
loon livers. There was a negative correlation between mercury and selenium in eggs.
Received: 2 February 2001/Accepted: 28 May 2001 相似文献