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991.
This paper analyses the role of computers within the nursery sector and what are viewed as the potential benefits and concerns of introducing young children to computers. It also examines how the computer is introduced and presented to young children and the form it takes. Data collection comprises a number of methods: questionnaires, semi-structured observations of children using the computer in the nursery setting and interviews with nursery school teachers. Findings indicate that, where computers are present, they appear to be incorporated as a Play Centre where children are provided with adult support. The programs used tend to focus on early literacy and mathematics. Although organizational approaches vary across settings, it would seem that teachers who incorporate their use find computers providing a positive learning experience for young children who, in turn, are highly motivated and keen to exercise their emergent Information and Communications Technology skills.  相似文献   
992.
Reacting to a pandemic influenza outbreak will require the mass distribution of vaccine, when available, which will require county health departments to set up and operate one or more mass vaccination clinics, also known as points of dispensing (PODs). Carefully planning these PODs before an event occurs is a difficult but important job. First, this article describes a tool--the Clinic Planning Model Generator computer program--designed to help public health agencies evaluate and make adjustments to their POD plans. The Clinic Planning Model Generator was built on data from a smallpox exercise and other biological agent POD exercises. Second, this article demonstrates the application of the Clinic Planning Model Generator through an example pandemic influenza scenario. This work is the result of an ongoing collaboration between Montgomery County, Maryland's Advanced Practice Center for Public Health Emergency Preparedness and Response, and the Institute for Systems Research at the University of Maryland.  相似文献   
993.
994.
Recent innovations to improve employment rates among persons with psychiatric disabilities include hybrid case management/employment services. Project WINS was a research/demonstration project which integrated specialized vocational services into case management teams. In this report, client outcomes of WINS involvement are evaluated, using a quasiexperimental, longitudinal design. On almost all the work-related variables, participants in the immediate and delayed treatment conditions displayed better outcomes than those in the control condition, as did individuals receiving moderate or substantial service versus no/minimal services. To address possible selection bias due to the quasiexperimental nature of the design, further analyses used baseline differences across conditions and participation levels as covariates. Results of multivariate analyses showed some anomalous findings regarding significant positive effects for the delayed, but not the immediate treatment condition versus the no-treatment control group. However, in similar analyses involving participation level as the independent variable, a moderate or substantial amount of service increased the odds of working by almost five times and also positively affected three other work-related variables. While limitations of this quasiexperimental design are noted, the results appear promising enough to support replications of WINS.  相似文献   
995.
PURPOSE: The purpose of the present study was to evaluate a boronated EGFRvIII-specific monoclonal antibody, L8A4, for boron neutron capture therapy (BNCT) of the receptor-positive rat glioma, F98(npEGFRvIII). EXPERIMENTAL DESIGN: A heavily boronated polyamido amine (PAMAM) dendrimer (BD) was chemically linked to L8A4 by two heterobifunctional reagents, N-succinimidyl 3-(2-pyridyldithio)propionate and N-(k-maleimidoundecanoic acid)hydrazide. For in vivo studies, F98 wild-type receptor-negative or EGFRvIII human gene-transfected receptor-positive F98(npEGFRvIII) glioma cells were implanted i.c. into the brains of Fischer rats. Biodistribution studies were initiated 14 days later. Animals received [(125)I]BD-L8A4 by either convection enhanced delivery (CED) or direct i.t. injection and were euthanized 6, 12, 24, or 48 hours later. RESULTS: At 6 hours, equivalent amounts of the bioconjugate were detected in receptor-positive and receptor-negative tumors, but by 24 hours the amounts retained by receptor-positive gliomas were 60.1% following CED and 43.7% following i.t. injection compared with 14.6% ID/g by receptor-negative tumors. Boron concentrations in normal brain, blood, liver, kidneys, and spleen all were at nondetectable levels (<0.5 microg/g) at the corresponding times. Based on these favorable biodistribution data, BNCT studies were initiated at the Massachusetts Institute of Technology Research Reactor-II. Rats received BD-L8A4 ( approximately 40 microg (10)B/ approximately 750 mug protein) by CED either alone or in combination with i.v. boronophenylalanine (BPA; 500 mg/kg). BNCT was carried out 24 hours after administration of the bioconjugate and 2.5 hours after i.v. injection of BPA for those animals that received both agents. Rats that received BD-L8A4 by CED in combination with i.v. BPA had a mean +/- SE survival time of 85.5 +/- 15.5 days with 20% long-term survivors (>6 months) and those that received BD-L8A4 alone had a mean +/- SE survival time of 70.4 +/- 11.1 days with 10% long-term survivors compared with 40.1 +/- 2.2 days for i.v. BPA and 30.3 +/- 1.6 and 26.3 +/- 1.1 days for irradiated and untreated controls, respectively. CONCLUSIONS: These data convincingly show the therapeutic efficacy of molecular targeting of EGFRvIII using either boronated monoclonal antibody L8A4 alone or in combination with BPA and should provide a platform for the future development of combinations of high and low molecular weight delivery agents for BNCT of brain tumors.  相似文献   
996.

Background  

The optimal cancer treatment for an older population is largely unknown because of the low numbers of elderly patients accrued into clinical trials. This project focuses on the attitudes of the elderly about participation in clinical trials to determine if this is one of the barriers to the involvement of this population in clinical trials.  相似文献   
997.
Conclusions Limited-stage HL is highly curable. Fiveyear progression-free survival in this study favors the RT-containing treatments. However, no significant difference was found in event-free and overall survival at 5 years. The progression-free survival benefit for patients receiving RT-containing therapy was offset by additional toxicity, including a higher rate of second cancers and cardiovascular events. For those patients in the chemotherapy-alone arms who achieved a CR or CRu after two cycles of ABVD, the progression-free survival rate was 95% with only four cycles total of ABVD administered. This result was similar to the 5-year progression-free survival rate of the RT-containing arms.  相似文献   
998.
PURPOSE: This open-label study assessed the safety and immunogenicity of two doses and two routes of the anti-idiotypic monoclonal antibody abagovomab (formerly ACA125) in patients with epithelial ovarian, fallopian tube, or primary peritoneal cancer. EXPERIMENTAL DESIGN: Eligible patients from the three participating institutions were any stage at diagnosis, had relapsed, and had complete or partial response to additional chemotherapy. Patients were randomized to receive abagovomab at 2.0 versus 0.2 mg and i.m. versus s.c. for four immunizations every 2 weeks and then monthly for two additional immunizations. Planned evaluation included interval physical examinations and laboratory assessments with immune assessment, including HLA typing, human anti-mouse antibody, ELISA, and enzyme-linked immunospot. Patients were required to remain on study until week 10 (the first post-baseline Ab3 determination) to be considered for immunologic assessment. The primary end points were safety and immunogenicity primarily determined by Ab3 response. RESULTS: Forty-two patients received at least one vaccination and were eligible for safety analysis. Thirty-three patients were available for Ab3 analysis (removed for progression of disease, 6; withdrawal of consent, 2; unrelated adverse event, 1). The most common adverse events were self-limited pain at injection site, myalgia, and fever. No hematologic or nonhematologic toxicity grade>2 related to immunization was seen. Ab3 was detectable in all patients (median, 236,794 ng/mL); none of route of administration (P=0.6268), dose (P=0.4602), or cohort (P=0.4944) was statistically significant in terms of effect on maximum post-baseline Ab3 titer. Human anti-mouse antibody was not detectable at baseline but was present in all patients at week 16 (range, 488-45,000 ng/mL). CONCLUSIONS: Immunization with abagovomab is well tolerated and induced robust Ab3 responses at the two doses and routes tested. A phase III randomized study with abagovomab (2.0 mg s.c.) is warranted.  相似文献   
999.
This study examines, in 11 cynomolgus monkeys with unilateral laser-induced glaucoma, the ocular hypotensive mechanism of action of AL-6598, partial agonist at the DP and EP prostanoid receptors. In a crossover fashion, both eyes of each monkey were dosed twice daily with 25 microL of either AL-6598 0.01% or vehicle for 2 days and on the morning of the 3rd day. Measurements were made on day 3 of each treatment. Alternative treatments were separated by at least 2 weeks. Intraocular pressures (IOPs) were measured by pneumatonometry and aqueous flow and outflow facility by fluorophotometry. Uveoscleral outflow was calculated mathematically. In the normotensive eyes, compared to vehicle treatment, AL-6598 decreased IOP from 22.5 +/- 0.7 to 18.7 +/- 0.9 mmHg (P = 0.006), increased uveoscleral outflow from 0.47 +/- 0.17 to 1.22 +/- 0.17 microL/min (P = 0.03), and increased aqueous flow from 1.49 +/- 0.10 to 1.93 +/- 0.13 microL/min (P = 0.01). No measurement in AL-6598-treated hypertensive eyes was significantly different from vehicle treatment. It is concluded that AL-6598 reduces IOP by increasing uveoscleral outflow in normotensive eyes of ketamine-sedated monkeys, despite an increase in aqueous flow. This effect is different from that of PGD(2), which decreases aqueous flow, and of the selective DP receptor agonist, BW245C, which increases both outflow facility and uveoscleral outflow in addition to decreasing aqueous flow.  相似文献   
1000.
PURPOSE: To investigate the activity of a novel dioxolane L-nucleoside analog, troxacitabine (L-(-)-OddC, BCH-4556), in patients with refractory leukemia. PATIENTS AND METHODS: Study participants were patients with refractory or relapsed acute myeloid (AML) or lymphocytic (ALL) leukemia, myelodysplastic syndromes (MDS), or chronic myelogenous leukemia in blastic phase (CML-BP). Troxacitabine was provided as an intravenous infusion for more than 30 minutes daily for 5 days at a dose of 8.0 mg/m(2)/d (40 mg/m(2) per course). Courses were given every 3 to 4 weeks according to antileukemic efficacy. RESULTS: Forty-two patients (AML, 18 patients; MDS, one patient; ALL, six patients; CML-BP, 17 patients) were treated. Median age was 51 years (range, 23 to 80 years); 22 patients were male. Stomatitis was the most significant adverse event, with three patients (7%) and two patients (5%), respectively, experiencing grade 3 or 4 toxicity. Ten patients (24%) had grade 3 hand-foot syndrome, and two patients (5%) had grade 3 skin rash. One patient (2%) had grade 3 fatigue and anorexia. Marrow hypoplasia occurred between days 14 and 28 in 12 (75%) of 16 assessable patients with AML. Two complete remissions and one partial remission (18%) were observed in 16 assessable patients with AML. None of six patients with ALL responded. Six (37%) of 16 assessable patients with CML-BP experienced a return to chronic-phase disease. CONCLUSION: Troxacitabine has significant antileukemic activity in patients with AML and CML-BP.  相似文献   
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