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11.
The authors examined variables differentiating singly and multiply victimized youth with a national household probability sample of 4,023 adolescents. Youth endorsing one episode (i.e., one incident or series of repeat incidents) of sexual or physical assault were classified as singly victimized (n = 435). Multiply victimized youth were those who endorsed multiple discrete episodes of sexual or physical assault and both sexual and physical assault (n = 396). For boys, heightened risk of multiple victimization was associated with family alcohol problems, Native American race, and earlier age at assault onset. For girls, increased multiple victimization risk was associated with family alcohol problems, older current age, and several characteristics of the initial assault episode-earlier age at onset, acquaintance perpetrator, chronicity, perceived life threat, and injury. Findings imply that secondary prevention programs may be strengthened by broadening risk-reduction strategies to address a greater range of victimization experiences. Additional implications for secondary prevention are discussed.  相似文献   
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The prevalence of methicillin-resistant and multiply antibiotic-resistant staphylococci causing infections in hospitalized patients was studied over a two-year period. Among 122 clinically significant staphylococci, the prevalence of methicillin resistance was 66 %, with a higher prevalence ofStaphyloccus haemolyticus (85 %) andStaphylococcus epidermidis (83 %) observed than ofStaphylococcus aureus (49 %). Multiple antibiotic resistance was observed more frequently among coagulase-negative staphylococci (52 to 70 %) than amongStaphylococcus aureus (17 %). All strains of methicillin-resistantStaphylococcus aureus were susceptible to glycopeptide antibiotics and to trimethoprim-sulfamethoxazole, whereas approximately 50 % of coagulase-negative staphylococci exhibited either moderate susceptibility or resistance to teicoplanin. For these latter strains, vancomycin remains the agent of choice, whereas teicoplanin cannot be recommended unless its efficacy is established by MIC determination.  相似文献   
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OBJECTIVE: This study compared diabetes Treatment As Usual (TAU) with Pathways To Change (PTC), an intervention developed from the Transtheoretical Model of Change (TTM), to determine whether the PTC intervention would result in greater readiness to change, greater increases in self-care, and improved diabetes control. RESEARCH DESIGN AND METHODS: Participants were stratified by diabetes treatment and randomized to treatment with PTC or TAU as well as being randomized regarding receipt of free blood testing strips. The PTC consisted of stage-matched personalized assessment reports, self-help manuals, newsletters, and individual phone counseling designed to improve readiness for self-monitoring of blood glucose (SMBG), healthy eating, and/or smoking cessation. A total of 1029 individuals with type 1 and type 2 diabetes who were in one of three pre-action stages for either SMBG, healthy eating, or smoking were recruited. RESULTS: For the SMBG intervention, 43.4% of those receiving PTC plus strips moved to an action stage, as well as 30.5% of those receiving PTC alone, 27.0% of those receiving TAU plus strips, and 18.4% of those receiving TAU alone (P < 0.001). For the healthy eating intervention, more participants who received PTC than TAU (32.5 vs. 25.8%) moved to action or maintenance (P < 0.001). For the smoking intervention, more participants receiving PTC (24.3%) than TAU (13.4%) moved to an action stage (P < 0.03). In intention-to-treat (ITT) analysis of those receiving the SMBG intervention, PTC resulted in a greater reduction of HbA(1c) than TAU, but this did not reach statistical significance. However, in those who moved to an action stage for the SMBG and healthy eating interventions, HbA(1c) was significantly reduced (P < 0 0.001). Individuals who received the healthy eating intervention decreased their percentage of calories from fat to a greater extent (35.2 vs. 36.1%, P = 0.004), increased servings of fruit per day (1.89 vs. 1.68, P = 0.016), and increased vegetable servings (2.24 vs. 2.06, P = 0.011) but did not decrease weight. However, weight loss for individuals who received the healthy eating intervention and who increased SMBG frequency as recommended was significantly greater, with a 0.26-kg loss in those who remained in a pre-action SMBG stage but a 1.78-kg loss in those performed SMBG as recommended (P 相似文献   
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OBJECTIVES: To identify diabetes-related characteristics of individuals at different stages of readiness to change to healthy, low-fat eating. RESEARCH DESIGN AND METHODS: Stage-based differences in demographic, eating-related, health care utilization, and psychosocial factors were examined in a sample of 768 overweight (BMI >27 kg/m(2)) individuals with diabetes enrolled in a randomized behavioral intervention trial. RESULTS: Stage-based differences occurred for type 1 diabetic participants on percent of calories from fat and number of daily vegetable servings. For type 2 diabetic participants, sex, disease-specific quality of life, percent calories from fat, and number of daily vegetables servings differed across stages. Those in action stages were more likely to be female and have a better quality of life and healthier eating habits. Type 2 diabetic insulin-requiring participants in action stages were more likely to be married. Social support was highest for those in the contemplation stage and lowest for those in the action stage. Type 2 diabetic participants on pills in the action stages were older, had a lower BMI, ate more fruit, were nonsmokers, recently attended diabetes education, had a better quality of life and social support, and had less stress. One anomalous finding for type 2 diabetic participants was that precontemplators scored similarly to those in action stages. CONCLUSIONS: These data validate the Transtheoretical Model, where those in the action stages displayed healthier eating. They also indicate that demographic and psychosocial factors may mediate readiness to change diet. Precontemplators were a heterogeneous group and may need individually tailored interventions.  相似文献   
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To determine the pattern and significance of the HCV genetic heterogeneity before and during treatment with recombinant-2b or lymphoblastoid alpha-interferon, hypervariable region 1 (HVR-1) and NS5A quasispecies were characterised by cloning and sequencing in 12 HCV-1b-infected subjects. Patients were either responder-relapsers or non-responders to treatment. Extensive amino acid sequence analysis was applied to reveal the significance of HCV variation at key sites within HVR-1 and NS5A regions. Genetic complexity, genetic diversity, and the non-synonymous to synonymous substitution ratios of HVR-1 quasispecies decreased during treatment in responder-relapser patients only, and more markedly so following lymphoblastoid alpha-interferon. In non-responders, the HVR-1 quasispecies broadened. Amino acids G406 and Q409, which represent a major viral epitope, were highly conserved throughout treatment. Responder-relapser patients had a higher mutation frequency in NS5A than non-responders. Lymphoblastoid alpha-interferon promoted the selection of intermediate Interferon Sensitivity Determining Region (ISDR) sequences, whereas recombinant-2b alpha-interferon favoured maintenance or selection of conserved ISDR sequences. Variability upstream of the ISDR was associated with treatment response, but the amino acid substitutions conferring higher replicative ability to in vitro HCV replicons were absent in in vivo isolates. In conclusion, the pattern of HVR-1 quasispecies evolution correlates with the clinical response, and the conservation of specific amino acids may be useful for immune targeting in vivo. In responder-relapser patients, the initial HVR-1 evolution resembles that found in sustained responders. Variability within the entire NS5A, as opposed to a single region (ISDR), may have a role in influencing alpha-interferon treatment outcome. A differential effect of different alpha-interferon preparations on HCV quasispecies kinetics may exist.  相似文献   
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BACKGROUND: To evaluate the effect of chemotherapy on humoral immunity to vaccine-preventable disease, the authors investigated the persistence of protective antibody titers in a group of patients who were alive and well after they were treated for pediatric malignancies. METHODS: Serum antibody levels were evaluated for polio, tetanus, hepatitis B, rubella, mumps, and measles in 192 children. The terms lack of immunity and loss of immunity, respectively, were used to describe the absence of immunity in patients who were tested only after chemotherapy and in patients who were tested both before and after chemotherapy and determined to have immunity before chemotherapy. RESULTS: Overall, the absence of a protective serum antibody titer for hepatitis B, measles, mumps, rubella, tetanus, and polio was detected in 46%, 25%, 26%, 24%, 14%, and 7% of patients, respectively. On univariate analysis, loss of antibodies against rubella, mumps, and tetanus was associated significantly with younger age (P < 0.001, P = 0.02, and P = 0.001, respectively), and loss of antibodies against measles was significantly associated with younger age and female gender (P = 0.0003 and P = 0.008, respectively). The administration of 59 booster vaccinations to 51 patients who had lost > or = 1 protective antibody titer resulted in an overall response rate of 93%. CONCLUSIONS: Chemotherapy induced different rates of loss of protective antibody titers depending on the type of vaccination administered. This finding may be responsible for the failure of vaccination programs for patients who have undergone chemotherapy. The administration of a booster dose after the completion of chemotherapy is a simple and cost-effective way to restore humoral immunity against most vaccine-preventable diseases.  相似文献   
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