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81.
The role of p53, as a prognostic factor for survival in lung cancer, is controversial and the purpose of the present systematic review of the literature is to determine this effect. Published studies were identified with the objective to aggregate the available survival results after a methodological assessment using a scale specifically designed by the European Lung Cancer Working Party (ELCWP). To be eligible, a study had to deal with p53 assessment in lung cancer (primary site) only, and to provide a survival comparison according to the p53 status. Among the 74 eligible papers, 30 identified p53 abnormalities as a univariate statistically significant poor prognostic factor and 56 provided sufficient data to allow survival results aggregation. There was no significant difference between the trials that either showed or did not show a prognostic effect of p53 according to the methodological score or to the laboratory technique used. The studies were categorized by histology, disease stage, treatment and laboratory technique. Combined hazard ratios suggested that an abnormal p53 status had an unfavourable impact on survival: in any stage nonsmall cell lung cancer (NSCLC) the mean (95% confidence interval) was 1.44 (1.20-1.72) (number of studies included in the subgroup was 11), 1.50 (1.32-1.70) in stages I-II NSCLC (n=19), 1.68 (1.23-2.29) in stages I-IIIB NSCLC (n=5), 1.68 (1.30-2.18) in stages III-IV NSCLC (n=9), 1.48 (1.29-1.70) in surgically resected NSCLC (n=20), 1.37 (1.02-1.85) in squamous cell carcinoma (n=9), 2.24 (1.70-2.95) in adenocarcinoma (n=9), 1.57 (1.28-1.91) for a positive immunohistochemistry with antibody 1801 (n=8), 1.25 (1.09-1.43) for a positive immunohistochemistry with antibody DO-7 (n=16), and 1.65 (1.35-2.00) for an abnormal molecular biology test (n=13). Data were insufficient to determine the prognostic value of p53 in small cell lung cancer. In each subgroup of nonsmall cell lung cancer, p53 abnormal status was shown to be associated with a poorer survival prognosis.  相似文献   
82.
The prognostic value of epidermal growth factor receptor (EGF-R) for survival of patients with lung cancer remains controversial. The authors performed a systematic review of the literature in order to clarify its impact. Published studies were identified using an electronic search in order to aggregate the available survival results, after a methodological assessment using a scale specifically designed by the European Lung Cancer Working Party (ELCWP). To be eligible, a study had to have dealt with EGF-R assessment in lung cancer patients on the primary site and to have analysed survival according to EGF-R expression. Among the 16 eligible studies, 14 assessed any nonsmall-cell lung cancer (NSCLC) subtype, one adenocarcinoma only and one squamous-cell carcinoma only. The overall median quality score was 56.3%, with no significant difference either between studies assessable or not assessable for meta-analysis or between studies with significant and nonsignificant results. One individual trial reported a survival benefit for patients with EGF-R expression, three a survival disadvantage and 12 no statistically significant difference. Eleven studies (2,185 patients) provided sufficient data to allow a meta-analysis of the survival results. EGF-R expression positivity was determined according to the cut-off as determined by the authors. The meta-analysis showed that EGF-R expression was not a statistically significant prognostic factor for survival in NSCLC. In the subgroup of studies using immunohistochemistry, statistical tests reached a significant level against EGF-R. Epidermal growth factor receptor might be a poor prognostic factor for survival in nonsmall-cell lung cancer. The amplitude of the impact is small, however, and may be subject to publication bias.  相似文献   
83.
Osteogenesis imperfecta (OI) is typically caused by mutations in type 1 collagen genes, but in recent years new recessive and dominant forms caused by mutations in a plethora of different genes have been characterized. OI type V is a dominant form caused by the recurrent (c.‐14C > T) mutation in the 5'UTR of the IFITM5 gene. The mutation adds five residues to the N‐terminus of the IFITM5, but the pathophysiology of the disease remains to be elucidated. Typical clinical features present in the majority of OI type V patients include interosseous membrane calcification between the radius and ulna and between the tibia and fibula, radial head dislocation, and significant hyperplastic callus formation at the site of fractures. We report a 5‐year‐old child with clinical features of OI type III or severe OI type IV (characteristic facies, gray sclerae, typical fractures) and absence of classical features of OI type V with a de novo recurrent IFITM5 mutation (c.‐14C > T), now typical of OI type V. This highlights the variability of OI caused by IFITM5 mutations and suggests screening for mutations in this gene in most cases of OI where type 1 collagen mutations are absent. © 2013 American Society for Bone and Mineral Research.  相似文献   
84.
Background: Alpha2-adrenoceptor agonists, such as clonidine, can potentiate the analgesic properties of spinal opioids. In order to further extend this observation to highly lipophilic and potent spinally acting opioids, we tested the interactions between clonidine and sufentanil after both epidural and intrathecal administration in rats.
Methods: The rats were equipped with spinal catheters. Antinociceptive testing was performed with the Tail Withdrawal Reaction test. Dose-response functions of sufentanil, clonidine and combinations of clonidine plus sufentanil were determined.
Results: These indicated that 1) sufentanil, but not clonidine alone, results in a dose-related antinociception after both the epidural and the intrathecal route of administration; 2) In combination with normally inactive doses of sufentanil, the addition of clonidine results in activity; 3) In a particular dose-range of sufentanil, there is a direct relationship between the doses of sufentanil and clonidine needed to produce antinociception; 4) Even at very high doses of clonidine, a minimal amount of sufentanil is needed to produce antinociception and 5) At the conditions tested here, the contribution of clonidine is minimal at high, intrinsic active doses of sufentanil.  相似文献   
85.
Ritanserin reduces abuse of alcohol, cocaine, and fentanyl in rats.   总被引:3,自引:0,他引:3  
Rats that had received 3% alcohol, 0.01% cocaine, or 0.002% fentanyl as the only beverage over 10 days showed marked preference for the drug solution when water was made available as a second fluid in a separate bottle. Treatment with low doses of ritanserin, a specific central serotonin 5-HT2 antagonist, rapidly reversed drug preference without changing total fluid intake. Quantitatively, the reduction in drug consumption was greater for alcohol than for cocaine and greater for cocaine than for fentanyl. This is probably related to differences in the reinforcing potential of the three drugs.  相似文献   
86.
Male Wistar rats were injected epidurally with various doses of sufentanil in 3 different dilution volumes, in order to determine differences in the lowest ED50 values for analgesia and side-effects. The lowest ED50 for both a TWR latency greater than 6 and greater than or equal to 10 s was significantly lower in the 20-microliters group as compared to the 2-microliters group. With an injection of 5 microliters, intermediate values were obtained. With regard to the side-effects, there was a trend towards increased systemic resorption with larger diluent volumes in spite of a better and more selective spinal effect, as evidenced by increasing specificity ratios. In terms of duration of analgesia at fixed doses of sufentanil, different results were obtained. At low doses of sufentanil, a pronounced diluent volume effect was present and the duration of analgesia increased as a function of the volume. At higher doses of sufentanil, however, the volume effect faded away and no differences were observed as a function of the diluent.  相似文献   
87.
Recognizing people involves creating and retrieving links between distinct representations such as faces and names. In previous research we have shown that the retrieval of face/name associations produced cerebral activities lateralized in the left hemisphere and spreading from posterior to anterior sites after about 300ms. The present ERP study was performed to compare the specific electrophysiological activities elicited by the retrieval of face/proper name (FP) and animal/common name (AC) associations. Using a subtraction method to isolate the specific binding activities, we showed that both kinds of association produced two main posterior negative/anterior positive complexes, with a more frontal distribution for AC, and bilateral temporal activities. These findings confirm that general associative processes - independent of the kind of association - are not simply the sum of the activities elicited by each stimulus, and that they could involve both unimodal sensory and multimodal convergence regions of the brain.  相似文献   
88.
End tidal CO(2) measurement may be helpful in detecting the efficacy of thrombolysis after a massive pulmonary embolism. We report the case of a 76-year-old man with a massive pulmonary embolism, who required early intubation and mechanical ventilation. Thrombolysis with rtpA (total dosage: 60 mg) was initiated. During this procedure, clinical data, arterial blood gases and end-tidal CO(2) with a capnograph were recorded. Before thrombolysis the P(a-ET)CO(2) gradient was raised to 25 mmHg. During thrombolysis, the clinical data improved and the P(a-ET) gradient fell to 14 mmHg. We postulate that the P(a-ET)CO(2) gradient seems to be a reasonable indicator of efficacy of thrombolysis in this setting. However, the gradient did not return to normal values (4-5 mmHg). The possible reasons for this may be that during mechanical ventilation there was a large ventilation-perfusion ratio and the cardiac output may have still reduced. With these limitations, we conclude that the P(a-ET)CO(2) gradient should be evaluated as an indicator of pulmonary reperfusion in massive pulmonary embolism.  相似文献   
89.
Objective To assess the effect of continuous venovenous hemodiafiltration (CVVHDF) in cancer patients with acute renal failure.Patients and methods Retrospective study of all patients with acute renal failure requiring dialysis and treated with CVVHDF in a medical intensive care unit (ICU) from a cancer hospital.Results From January 1997 until December 2002, 32 cancer patients were treated with CVVHDF for acute renal failure. Their characteristics were: male/female 23/9, median age 61 years, haematological/solid tumours 16/16, and median APACHE II and IGS II scores 31/67. The number of organ failures was 1/2/3/4 in respectively 10/6/13/2 patients. Complete, partial or absence of resolution of acute renal failure was noted in 13, 8 and 11 patients. Sixteen patients (50%) died in the ICU and 15 (47%) were discharged alive from the hospital. In univariate analysis, variables statistically significantly adversely associated with hospital mortality were renal failure of renal origin, bone marrow transplant, increasing number of organ failures, reduced lymphocyte count, elevated bilirubin and lower creatinine levels, increased thromboplastin time, younger age, increased APACHE II and IGS II, ARDS and mechanical ventilation. In multivariate analysis, two models were used including either APACHE II or IGS II. The number of organ failures was found as the only significant prognostic factor in both models (p=0.01). Elevated phosphate level was a poor prognostic factor for hospital mortality (p=0.04) in the model including APACHE II.Conclusions In the experience of a single centre, CVVHDF is effective in the treatment of acute renal failure in cancer patients. The increasing number of organ failures was the single independent poor predictive factor for hospital mortality. Cancer characteristics and general gravity scores were not predictive factors.  相似文献   
90.
We have investigated the roles of peripheral and central mu, delta, and kappa opioid receptors and their subtypes in opioid-induced hypothermia in mice. Measuring rectal temperature after i.p. injection, opioid agonists [morphine, fentanyl, SNC80 ((+)-4-[(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)3-methoybenzyl]-N,N-diethylbenzamide), U50,488H ((trans-(dl)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl]-benzeneacetamide), and loperamide)] were tested alone or with opioid antagonists [naloxone, beta-funaltrexamine, naloxonazine, naltrindole, 7-benzylidenenaltrexone (BNTX), naltriben, nor-binaltorphimine, 2-(3,4-dichlorophenyl)-N-methyl-N-[(1S)-1-(3-isothiocyanatophenyl)-2-(1-pyrrolidinyl)ethyl]acetamide (DIPPA), and methyl-naltrexone] given 15 min after the agonist. All agonists produced dose-related hypothermia, although at low doses, morphine and U50,488H produced hyperthermia. The effects of morphine and fentanyl were antagonized by naloxone and by the mu(1) antagonist naloxonazine. The delta(2) antagonist naltriben potentiated the hypothermic effect of mu agonists. SNC80-induced hypothermia was blocked by the delta antagonist naltrindole but not by the delta(1) antagonist BNTX. Depending on the dose, the delta(2) antagonist naltriben produced either a potentiation or an attenuation of the effect of SNC80. U50,488H-induced hypothermia was antagonized by the kappa antagonist nor-binaltorphimine but not by acute treatment with the irreversible kappa antagonist DIPPA. The peripherally acting opioid loperamide produced hypothermia that could be blocked by several mu-, delta-, or kappa-selective antagonists as well as the peripherally acting antagonist methyl-naltrexone. Methyl-naltrexone produced a weak potentiation of morphine-, fentanyl-, and U50,488H-induced hypothermia, whereas a significant attenuation of SNC80-induced hypothermia was observed. In conclusion, at high doses, morphine- and fentanyl-induced hypothermia may involve composite action on mu, kappa, and possibly delta opioid receptors after initial activation. In the mediation of delta opioid-induced hypothermia, no clear selectivity between the delta(1) and delta(2) subtypes was defined. The studies provide new evidence that maintenance of the initial effects of agonist/receptor activation vary with the agonist and the receptor. The existence of both central and peripheral components of opioid-induced hypothermia is also emphasized.  相似文献   
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