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121.
Paul Rohde Christopher W Kahler Peter M Lewinsohn Richard A Brown 《Nicotine & tobacco research》2004,6(3):509-522
The present study examined whether lifetime psychopathology, regular smoking and psychopathology in family members, and smoking characteristics were associated with successful cessation among daily smokers. A sample of 941 young adults was interviewed for lifetime psychopathology and smoking at three time points; biological parents and siblings were interviewed once for lifetime psychopathology and regular smoking. Within the subset of 242 daily smokers with complete data, most (83%) had tried to quit at least once, although only 22% met our definition of successful cessation (no smoking during the 12 months prior to turning age 25 years). Successful cessation was positively associated with being married and having a higher household income in young adulthood, and negatively associated with lifetime major depressive disorder, elevated antisocial personality disorder symptoms, a family history of drug and alcohol use disorder, and nicotine dependence (for women but not men). Marital status, nicotine dependence (for women but not men), and male gender were significant in multivariate analyses; the effect for major depressive disorder approached significance (p=.052). None of the measures of familial smoking were associated with successful smoking cessation. In conclusion, whereas almost all Axis I disorders in our two previous papers were associated with smoking initiation and progression to daily smoking, major depressive disorder and antisocial personality disorder symptoms were the only psychiatric conditions negatively associated with successful cessation. The causal nature of the significant associations and the degree to which modification of these factors increases the probability of future smoking cessation deserve further attention. 相似文献
122.
JP van Leeuwen M Pruszczynski HA Marres JA Grotenhuis CW Cremers 《Canadian Metallurgical Quarterly》1995,109(12):1186-1189
A case report of a six-year-old child is presented, who had had a unilateral sensorineural hearing loss for several years. Because of impairment in the ABR as well as in the caloric testing a MRI and CT scan were performed. A 17 mm tumour in the cerebellopontine angle (CPA) was detected, which after suboccipital surgery proved to be a rhabdomyoma. This tumour has not been described before in the CPA. Unilateral sensorineural hearing loss should, at all ages, be an indication for further (radiodiagnostic) investigations. 相似文献
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Current standard therapy for distant metastatic melanoma is ineffective and often compromises the quality of a patient's life. Immunotherapy is briefly reviewed in relation to its many forms: from local non-specific to the more recent specific vaccines, including those using specific melanoma peptides (e.g. from the proteins encoded by melanoma-associated gene (MAGE)) and those involving genetically transduced autologous melanoma cells using retroviral vectors in vitro. The mode of action of genetically transduced melanoma cells incorporating the granulocyte macrophage colony stimulating factor (GM-CSF) gene (GVAX) is presented as a paradigm for cytokine-mediated strategies. Trials of GVAX and other cytokine gene strategies are under way in Brisbane, Boston and Amsterdam, and some interim perspectives on the clinical outcomes and immunological mechanisms involved are sketched. Some of the compounding problems in immunotherapeutic strategies for cancer are identified, and possible adjunct manoeuvres for overcoming them are discussed. 相似文献
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The study on the solvent extraction for quantitative and selective separation of total rare earth metals from the polymetallic nodule leach liquor was investigated. The typical leach liquor bearing 0. 094 g/L total rare earth, 0. 23 g/L Mn, 0.697 g/L Cu, 0.2 g/L Fe, 0.01 g/L Co and 0.735 g/L Ni was subjected to the removal iron content by precipitation method using Ca(OH)2 at pH 3.95, prior to solvent extraction of rare earth metals. Three different organo-phosphoric acid reagents(D2EHPA, PC88 A, Cyanex 272) were used to ascertain their performances and selectivity towards the loading of rare earth metals in presence of other base metals. Based on the results of eq. pH effect, the performances of above three extractants followed the order as: D2EHPA>PC88A>Cyanex 272. To ensure the absence of extraction of base metals(Cu, Co, Ni), the eq. pH of the solution was optimized at the level of 2.21, though higher rare earth metal extraction efficiency was observed at higher eq. pH with either of the extractants. The complete process flow diagram for substantial recovery of total rare earth was developed using D2 EHPA. Extraction isotherm plot was constructed at A:O=12:1, 3-stages and pHe=2.21, using 0.8 mol/L D2 EHPA and the predicted condition of this study was further confirmed by 6-Cycles Counter Current Simulation(CCS) study. The stripping of total rare earth from loaded organic phase(LO) was conducted using HCl solution. Mc-Cabe Thiele diagram study carried out at A:O=1:5 using 4 mol/L HCl showed that three theoretical stages were needed for quantitative stripping of total rare earth. The subsequent stripped solution resulted thus led to contain total rare earth of 5.6 g/L indicating a very high enrichment of total metals by solvent extraction(SX) process. 相似文献
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Amy M. Kahler Theresa L. Cromeans Jacquelin M. RobertsVincent R. Hill 《Water research》2011,45(4):1745-1751
There is a need for more information regarding monochloramine disinfection efficacy for viruses in water. In this study, monochloramine disinfection efficacy was investigated for coxsackievirus B5 (CVB5), echovirus 11 (E11), murine norovirus (MNV), and human adenovirus 2 (HAdV2) in one untreated ground water and two partially treated surface waters. Duplicate disinfection experiments were completed at pH 7 and 8 in source water at concentrations of 1 and 3 mg/L monochloramine at 5 and 15 °C. The Efficiency Factor Hom (EFH) model was used to calculate CT values (mg-min/L) required to achieve 2-, 3-, and 4-log10 reductions in viral titers. In all water types, monochloramine disinfection was most effective for MNV, with 3-log10 CT values at 5 °C ranging from 27 to 110. Monochloramine disinfection was least effective for HAdV2 and E11, depending on water type, with 3-log10 CT values at 5 °C ranging from 1200 to 3300 and 810 to 2300, respectively. Overall, disinfection proceeded faster at 15 °C and pH 7 for all water types. Inactivation of the study viruses was significantly different between water types, but there was no indication that overall disinfection efficacy was enhanced or inhibited in any one water type. CT values for HAdV2 in two types of source water exceeded federal CT value recommendations in the US. The results of this study demonstrate that water quality impacts the inactivation of viruses and should be considered when developing chloramination plans. 相似文献
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