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991.
L C Ingram D L Fairclough W L Furman J T Sandlund L E Kun G K Rivera C H Pui 《Cancer》1991,67(9):2262-2268
Forty-five children with acute lymphoblastic leukemia or non-Hodgkin's lymphoma had cranial nerve palsy (CNP) as a complication of their disease. Twenty-two of these children had CNP initially and 23, at relapse, with or without previous hematologic relapse. Only one of the 23 patients with CNP at relapse was a long-term survivor. In contrast, 11 of the 22 children who had CNP initially survived in remission for 3+ months to 13+ years. Two factors are associated with an improved outcome for patients with CNP at diagnosis: treatment after 1979 (P less than 0.004) and male gender (P less than 0.01). Patients who received radiation therapy fared better than those for whom radiation was not given (disease-free survival at 2 years 53% versus 29%). The authors conclude that CNP signifies an aggressive or advanced disease requiring intensive systemic chemotherapy and that the role of irradiation should be examined for this group of patients. 相似文献
992.
Fernando I Soriano Lourdes M Rivera Kara J Williams Sandra P Daley Vivian M Reznik 《The Journal of adolescent health》2004,34(3):169-176
The purpose of this paper is to review three cultural concepts (acculturation, ethnic identity, bicultural self-efficacy) and their relationship to the known risk and protective factors associated with youth violence. We conducted a review of the relevant literature that addresses these three cultural concepts and the relationship among culture, violent behavior, and associated cognition. The available literature suggests that ethnic identity and bicultural self-efficacy can be best thought of as protective factors, whereas acculturation can be a potential risk factor for youth violence. We examine the connection between these cultural concepts and the risk and protective factors described in the 2001 Surgeon General's Report on Youth Violence, and present a summary table with cultural risk and protective factors for violence prevention. These concepts can assist physicians in identifying risk and protective factors for youth violence when working with multicultural adolescents and their families. Physicians are more effective at providing appropriate referrals if they are aware that navigating among different cultures influences adolescent behavior. 相似文献
993.
A pilot study of detection of DNA adducts in white blood cells of roofers by 32P-postlabelling 总被引:1,自引:0,他引:1
R Herbert M Marcus M S Wolff F P Perera L Andrews J H Godbold M Rivera M Stefanidis X Q Lu P J Landrigan 《IARC scientific publications》1990,(104):205-214
To assess the utility of DNA adducts as biomarkers of exposure to carcinogens in an industrial population, a pilot study of roofers occupationally exposed to a mixture of polycyclic aromatic hydrocarbons was conducted. DNA was isolated from peripheral white blood cells of roofers and non-occupationally exposed subjects matched for age, sex and smoking status. Occupational exposures to anthracene, fluoranthene, pyrene, benzanthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[g,h,i]perylene and benzo[k]fluoranthene were assessed by personal breathing zone air sampling and skin wipes. Exposures to benzo[a]pyrene in air of exposed subjects ranged from 0.60 microgram/m3 to 1.39 micrograms/m3, and exposures to total polycyclic aromatic hydrocarbon (the sum of eight hydrocarbons) ranged from 6.0 micrograms/m3 to 13.8 micrograms/m3 on the day before blood collection. In the biomarker studies 10 of 12 roofers, but only 2 of 12 comparison subjects, had detectable levels of aromatic DNA adducts by 32P-postlabelling assay (p less than 0.01). The two non-roofers with detectable adducts had levels at or near the detection limit of 2 adducts per 10(9) nucleotides. In two roofer samples which were studied in a mixing experiment, the major adduct spots did not co-migrate with the guanosine N2 adduct of benzo[a]pyrene diol epoxide. These results suggest that the 32P-postlabelling assay may be useful for monitoring exposures to complex mixtures of aromatic hydrocarbons in industrial populations. 相似文献
994.
A high frequency of conversion from L1 to L2 morphology in ALL at relapse has been reported in studies made without benefit of the French-American-British (FAB) scoring system. We compared the lymphoblast morphology at presentation and first hematologic relapse for 50 consecutive children with acute lymphoblastic leukemia using the FAB scoring system to determine the frequency of morphologic conversion. Forty-eight patients presented with L1 morphology, 42 of whom (88%) relapsed with L1 blasts, four (8%) with L2 blasts, and two (4%) with blasts intermediate between L1 and L2. Two presented with L2 morphology, both relapsing with L2 blasts. These data do not support previous findings of a high frequency of conversion from L1 to L2 at relapse. They suggest, instead, that L2 morphology is not a common morphologic expression of initial treatment failure. 相似文献
995.
Pregnancy after renal transplantation 总被引:1,自引:0,他引:1
F L Gaudier E Santiago-Delpin J Rivera Z Gonzales 《Surgery, gynecology & obstetrics》1988,167(6):533-543
996.
997.
Determination and metabolism of dithiol chelating agents. VIII. Metal complexes of meso-dimercaptosuccinic acid 总被引:1,自引:0,他引:1
Metal complexes of meso-dimercaptosuccinic acid (DMSA) with Pb2+, Cd2+, and Hg2+ were studied by potentiometric and infrared methods. This dimercapto metal-binding agent was found to form complexes whose structures are dependent on the metal ion to be complexed. In the cases of Pb2+ and Cd2+, one oxygen and one sulfur act as the donor atoms; in the case of Hg2+, two sulfur atoms act as the donors. The solubilities of all metal chelates were found to be pH dependent. Complexes of cadmium and lead are insoluble in the pH range 1.0 to 7.1, but are solubilized when the noncoordinated sulfhydryl and carboxylic acid groups are ionized. The mercury complex is insoluble in the pH range 1.0 to 3.0. It dissolves when one of the noncoordinated carboxylic acid groups is ionized. The dimethyl ester of meso-DMSA (DiMe-meso-DMSA) was synthesized and its acid dissociation constants were determined (pK1 = 6.38 and pK2 = 8.00). Esterification of the carboxyl groups of meso-DMSA changes its coordination properties in that the two sulfur atoms of DiMe-meso-DMSA are used to coordinate with Hg2+, Cd2+, or Pb2+. Esterification of meso-DMSA also changes its biological properties. DiMe-meso-DMSA, when given to rats 3 days after Cd administration, greatly increased the excretion of Cd via bile. In contrast, meso-DMSA was devoid of such activity. 相似文献
998.
Epidemiological studies by international groups have shown a demographic structure which in Latin America, by the year 2000, will cause especially complex problems demanding important social, political and economic changes. Between them, they emphasize the overall increase of population size (more than doubling, from 280 to 600 million people), the large urban concentration (64% of the total population), with rural depopulation, on 18% decrease in fertility, and an increased life expectancy. With regard to this point, 36 Latin American and Caribean countries will have an average life expectancy of 65 years, and 19 of 70 years. Increased longevity, causing a large elderly population, is an achievment of civilisation, but is also an overwhelming problem. Biophysiological and psychological considerations of the ageing process are raised, as are the inherent problems of forced retirement, which have influence in working, emotional and family sheres, in a poorly-understanding society, too disorganized to provide help. This, by feedback, creates a special emotional deterioration in the elderly individual (considered for this purpose as being an age of more than 60 years for men, and 55 years for women), which is made considerably worse by increased incidence of illness. The need for, and importance of, social care for this group, which concalves health as part of the greater concept of wellbeing and quality of life, is emphasized. It shows how the modern concept of social welfare as part of the state, with reference to securing the wellbeing of the elderly, should not be a charity which is offered but an obligation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
999.
A Rivera R J Roberts J R Wispe 《JPEN. Journal of parenteral and enteral nutrition》1990,14(1):101-103
A technique and nutritional regimen for intravenous feeding of neonatal rabbits is described. Central venous nutrition of 40- to 60-g newborn rabbits was accomplished in a modified infant incubator using a specially constructed catheter and light-weight harness to provide nutrients by central vein for periods up to 7 days. Throughout the infusion period the newborn rabbits appeared healthy and evidenced increasing activity with age. The pups grew an average of 6.3 g/day, while receiving an intake of 150 to 200 kcal/kg/day. This model appears capable of being utilized to provide information on neonatal growth and metabolism in response to parenteral nutrition. 相似文献
1000.
A G Friedman R K Mulhern D Fairclough P M Ward D Baker J Mirro G K Rivera 《Medical and pediatric oncology》1991,19(6):499-504
The ability of midazolam, a benzodiazepine, to reduce the distress associated with lumbar puncture and bone marrow aspiration was examined in 23 children with acute lymphocytic leukemia. Patients were randomized to receive 0.2 mg/kg midazolam HCl or placebo intravenously 3-5 min before the procedures, under double-blind conditions. Based on prior experiences, children in both groups anticipated severe pain from these procedures. Postprocedure pain ratings by patients were markedly reduced in the midazolam but not the placebo group. Both physicians and parents judged the midazolam group as significantly less distressed than controls during and after the procedures. Trained observers recorded significantly fewer pain- and anxiety-related behaviors in the midazolam group immediately before and after, but not during the procedures. The amnestic effects of midazolam, confirmed in a visual recall/recognition test, appear to account for the decreased pain ratings since the behavioral manifestations were similar in the two groups. There were no adverse drug reactions or significant changes in vital signs. Midazolam warrants further investigation as a premedication for painful diagnostic and treatment procedures in children with cancer. 相似文献