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排序方式: 共有432条查询结果,搜索用时 15 毫秒
31.
Fulia F Cordaro S Meo P Gitto P Gitto E Trimarchi G Adelardi S Barberi I 《Biology of the neonate》2003,83(1):1-5
This study was carried out to determine whether the administration of antithrombin III decreases the risk of intraventricular hemorrhage in premature infants. In a randomized study, 60 infants born before 30 weeks of gestation were assigned to receive a loading dose of antithrombin III or placebo. There was no significant difference in the incidence of intraventricular hemorrhage between the antithrombin III and the placebo group (27.5 vs. 32%). Partial thromboplastin time, Quick's prothrombin time and platelet count were also not significantly different between the 2 groups. We conclude that the administration of antithrombin III during the first 2 days of life does not decrease incidence of intraventricular hemorrhage. Antithrombin III is a very expensive therapy and its benefits should be carefully investigated before being recommended as valuable therapy. 相似文献
32.
Even in the twenty-first century, welding is still a common and a highly skilled occupation. The hazardous agents associated with welding processes are acetylene, carbon monoxide, oxides of nitrogen, ozone, phosgene, tungsten, arsenic, beryllium, cadmium, chromium, cobalt, copper, iron, lead, manganese, nickel, silver, tin, and zinc. All welding processes involve the potential hazards for inhalation exposures that may lead to acute or chronic respiratory diseases. According to literature described earlier it has been suggested that welding fumes cause the lung function impairment, obstructive and restrictive lung disease, cough, dyspnea, rhinitis, asthma, pneumonitis, pneumoconiosis, carcinoma of the lungs. In addition, welding workers suffer from eye irritation, photokeratitis, cataract, skin irritation, erythema, pterygium, non-melanocytic skin cancer, malignant melanoma, reduced sperm count, motility and infertility. Most of the studies have been attempted previously to evaluate the effects of welding fumes. However, no collectively effort illuminating the general effects of welding fumes on different organs or systems or both in human has not been published. Therefore, the aim of this review is to gather the potential toxic effects of welding fumes documented by individual efforts and provide informations to community on hazards of welding. 相似文献
33.
L. Rigoli A. Meo M.R. Miceli K. Alessio R.A. Caruso M.A. La Rosa D.C. Salpietro M. Ricca I. Barberi 《International journal of laboratory hematology》2001,23(6):373-378
The prevalence of eight mutations in 84 patients with β‐thalassaemia major and in 16 subjects with thalassaemia intermedia was investigated. All of the patients were Italian, originating from Eastern Sicily (Messina area) and some Calabrian regions. Genomic DNA was amplified by polymerase chain reaction (PCR). DNA molecular investigations were performed by allele‐specific oligonucleotide (ASO) hybridization, to identify the following β‐thalassaemia mutations: CD39 (C‐T), IVS1‐110 (G‐A), IVS1‐6 (T‐C), IVS1‐1 (G‐A), IVS2‐745 (C‐G), IVS2‐1 (G‐A), ?87 (C‐G), CD6 A (?A). Our data underline that in thalassemia intermedia two mutations were statistically prevalent: IVS1‐6 T→C (P < 0.001) and CD 6‐A (P < 0.05). CD 39 was statistically prevalent in β‐thalassaemia major patients (P < 0.01). The difference between the two groups was not statistically significant for all the other mutations. Five different genotypes were recorded among thalassaemia intermedia and 15 among β‐thalassaemia major patients. Twenty‐five percent of the intermedia patients and 4.5% of the major patients had homozygosity for mild mutations (group I); 62.5% of the intermedia patients and 26.2% of the major patients had combinations of mild/severe mutations (group II). In addition, homozygosity or double heterozygosity for severe mutations (group III) was found in 12.5% of the intermedia patients and 69% of the major patients. Some genotypes were restricted to thalassaemia intermedia, including heterozygosity ?87/IVS1‐6 and IVS1‐6/CD 6‐A. It is essential to understand the distribution and frequency of the relevant mutations in each population where β‐thalassaemias exist. This is of particular importance for genotype–phenotype correlation and for carrier detection, genetic counselling and prenatal diagnosis. 相似文献
34.
W E Brown M G Magno P D Buckman F Di Meo D R Gale J D Mannion 《The Journal of surgical research》1991,51(1):54-59
This study was undertaken to evaluate the coronary collateral circulation of the goat. Year old, castrated male goats were anesthetized with sodium pentobarbital. A branch of the left circumflex coronary artery was dissected and a snare placed around it. Regional myocardial blood flow was measured by injecting colored microspheres into the left atrium before and during 3 hr of occlusion of this coronary artery. The Area At Risk for infarction, as defined by a left atrial injection of Brilliant Green dye, was divided into a central Ischemic zone and a peripheral Ischemic Border zone. The degree of overlap in the blood flow distributions between the risk and the nonrisk areas was quantitatively assessed by injecting microspheres directly into the artery to the Area At Risk. Baseline blood flow to the normally perfused goat myocardium was 1.13 +/- 0.18 ml/min/g (mean +/- SE). Following occlusion, the flow to the Ischemic zone was 0.07 +/- 0.03 ml/min/g and to the Ischemic Border zone was 0.31 +/- 0.18 ml/min/g. Flow to either zone did not increase during the 3-hr observation period. Overlap at the perimeter of the risk and nonrisk areas was approximately 22%. We conclude that flow to the Ischemic zone is low because the goat has few native collateral blood vessels, and that flow to the Ischemic Border zone is significantly affected by overlap with normal myocardium. 相似文献
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37.
Piero Manfredi Pompeo Della Posta Alberto d’Onofrio Ernesto Salinelli Francesca Centrone Claudia Meo Piero Poletti 《Vaccine》2009
A threat for vaccination policies might be the onset of “rational” exemption, i.e. the family's decision not to vaccinate children after a seemingly rational comparison between the perceived risk of infection and the perceived risk of vaccine side effects. We study the implications of rational exemption by models of vaccination choice. By a simple model of individual choice we first prove the “elimination impossible” result in presence of informed families, i.e. aware of herd immunity, and suggest that limited information might explain patterns of universal vaccination. Next, we investigate vaccination choice in a game-theoretic framework for communities stratified into two groups, “pro” and “anti” vaccinators, having widely different perceived costs of infection and of vaccine side effects. We show that under informed families neither a Nash nor a Stackelberg behaviour (characterized, respectively, by players acting simultaneously and by an asymmetric situation with a “leader” and a “follower) allow elimination, unless “pro-vaccinators” assign no costs to vaccine side effects. Elimination turns out to be possible when cooperation is encouraged by a social planner, provided, however, he incorporates in the “social loss function” the preferences of anti-vaccinators only. This allows an interpretation of the current Italian vaccination policy. 相似文献
38.
Caraglia M Marra M Viscomi C D'Alessandro AM Budillon A Meo G Arra C Barbieri A Rapp UR Baldi A Tassone P Venuta S Abbruzzese A Tagliaferri P 《International journal of cancer. Journal international du cancer》2007,121(10):2317-2330
Interferon alpha (IFNalpha) induces an EGF-Ras-->Raf-1-->Erk dependent survival pathway counteracting apoptosis induced by the cytokine. In this paper we have evaluated the effects of the combination between farnesyl-transferase inhibitor (FTI) R115777 and IFNalpha on the growth inhibition and apoptosis of cancer cells. Simultaneous exposure to R115777 and IFNalpha produced synergistic both antiproliferative and proapoptotic effects. In these experimental conditions, IFNalpha and R115777 completely antagonized the increased activity of both Ras and Erk-1/2 induced by IFNalpha and strongly reduced Akt activity. Furthermore, treatment with R115777 in combination with IFNalpha regimen induced tumor growth delay on established KB cell xenografts in nude mice, while the single agents were almost inactive. R115777 was again able to antagonize the Ras-dependent survival pathway induced by IFNalpha also in vivo. Raf-1, one of the downstream targets of Ras, has been reported to activate bcl-2 through displacement and/or phosphorylation of Bad. We have found that IFNalpha induced mitochondrial localization of Raf-1 that was antagonized by R115777. Moreover, IFNalpha increased Raf-1/bcl-2 immuno-conjugate formation and intracellular co-localization and enhanced phosphorylation of Bad at Ser 112 and again R115777 counteracted all these effects. Moreover, the use of plasmids encoding for dominant negative or dominant positive Raf-1 antagonized and potentiated, respectively, the co-immunoprecipitation between Raf-1 and bcl-2. In conclusion, FTI R115777 strongly potentiates the antitumor activity of IFNalpha both in vitro and in vivo through the inhibition of different survival pathways that are dependent from isoprenylation of intracellular proteins such as ras. 相似文献
39.
A single base deletion in the Tfm androgen receptor gene creates a short-lived messenger RNA that directs internal translation initiation. 总被引:15,自引:3,他引:12 下载免费PDF全文
40.