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991.
Uranotaenia sapphirina, Culex erraticus, and Cx. peccator were collected in an enzootic eastern equine encephalomyelitis (EEE) virus focus in central Alabama (Tuskegee National Forest) from 2001 to 2003 and analyzed for virus as well as host selection. EEE virus was detected in each species every year except 2003, when pools of Cx. peccator were negative. Most (97%) of the 130 Cx. peccator blood meals identified were from ectothermic hosts; 3% were from birds. Among blood meals from reptiles (approximately 75% of the total), 81% were from Agkistrodon piscivorus (cottonmouth); all amphibian blood meals (approximately 25%) were from Rana spp. with > 50% taken from the bullfrog R. catesbeiana. Host identifications were made from 131 of 197 Cx. erraticus, but only 3 (2%) were derived from ectothermic species. Identification of Ur. sapphirina blood meals proved difficult and only 2 of 35 hosts were determined. Both were from R. catesbeiana. Ectothermic species are possible EEE virus reservoirs in the southeastern United States where species such as Cx. peccator and Ur. sapphirina occur with large, diverse reptilian, amphibian, and avian populations such as those at the Tuskegee site.  相似文献   
992.
Background  Although previous studies suggest an association between provider burnout and suboptimal self-reported communication, no studies relate physician burnout to observed patient-physician communication behaviors. Objective  To investigate the relationship between physician burnout and observed patient-physician communication outcomes in patient-physician encounters. Design  Longitudinal study of enrollment data from a trial of interventions to improve patient adherence to hypertension treatment. Setting  Fifteen urban community-based clinics in Baltimore, MD. Participants  Forty physicians and 235 of their adult hypertensive patients, with oversampling of ethnic minorities and poor persons. Fifty-three percent of physicians were women, and the average practice experience was 11.2 years. Among the 235 patients, 66% were women, 60% were African-American, and 90% were insured. Measurements  Audiotape analysis of communication during outpatient encounters (one per patient) using the Roter Interaction Analysis System and patients’ ratings of satisfaction with and trust and confidence in the physician. Results  The median time between the physician burnout assessment and the patient encounter was 15.1 months (range 5.6–30). Multivariate analyses revealed no significant differences in physician communication based on physician burnout. However, compared with patients of low-burnout physicians, patients of high-burnout physicians gave twice as many negative rapport-building statements (incident risk ratio 2.06, 95% CI 1.58 – 2.86, p < 0.001). Physician burnout was not significantly associated with physician or patient affect, patient-centeredness, verbal dominance, or length of the encounter. Physician burnout was also not significantly associated with patients’ ratings of their satisfaction, confidence, or trust. Conclusions  Physician burnout was not associated with physician communication behaviors nor with most measures of patient-centered communication. However, patients engaged in more rapport-building behaviors. These findings suggest a complex relationship between physician burnout and patient-physician communication, which should be investigated and linked to patient outcomes in future research.  相似文献   
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BACKGROUND: The optimal virologic and immunologic stage at which to initiate antiretroviral therapy in individuals infected with human immunodeficiency virus type 1 (HIV-1) is undefined. METHODS: Among 1054 HIV-1-infected women in a prospective cohort study, we determined the time from initiation of highly active antiretroviral treatment (HAART) to acquired immunodeficiency syndrome (AIDS) and death. RESULTS: Median follow-up was 3.4 years. Of 553 women without AIDS at HAART initiation, 62 (11%) developed AIDS. Compared with women with CD4(+) cell counts greater than 350/microL at HAART initiation, women with cell counts of 200 to 350/microL and less than 200/microL had relative hazards (RHs) for progression to AIDS of 0.93 (95% confidence interval [CI], 0.46-1.86) and 2.48 (95% CI, 1.39-4.42), respectively. Compared with those with HIV-1 RNA values less than 5000 copies/mL, women with 5000 to 50,000 copies/mL and greater than 50,000 copies/mL had RHs of 1.39 (95% CI, 0.74-2.64) and 2.09 (95% CI, 1.09-3.99), respectively. Among women with AIDS at HAART initiation (n = 501), RHs of death were 1.97 (95% CI, 0.84-4.66) and 3.35 (95% CI, 1.59-7.08) with CD4(+) cell counts of 200 to 350/microL and less than 200/microL, respectively, relative to those with greater than 350/microL, and 1.90 (95% CI, 0.84-4.30) and 3.70 (95% CI, 1.81-7.54) for those with HIV-1 RNA values of 5000 to 50,000 and greater than 50,000 copies/mL, respectively, relative to those with less than 5000 copies/mL. CONCLUSIONS: Progression to AIDS and death was predicted by pre-HAART values of less than 200/microL for CD4(+) cells and greater than 50,000 HIV-1 RNA copies/mL, indicating that deferral of HAART until the CD4(+) cell count is between 350 and 200/microL is a valid strategy in the clinical management of HIV-1 infection.  相似文献   
994.
Distress and ad lib alcohol consumption after interactions with child confederates were investigated in parents of children with externalizing disorders—attention-deficit hyperactivity disorder (ADHD), conduct disorder (CD), or oppositional defiant disorder (ODD). Sixty subjects interacted with boys trained to act like either normal children or children with ADHD/CD/ODD. Interactions with deviant confederates resulted in feelings of inadequacy and produced negative affect but had no effect on alcohol consumption. Post hoc analyses showed that parents with a family history of alcohol problems (FH+) showed increased drinking after interaction with a deviant confederate, compared with FH+ parents who interacted with the normal confederate. FH- parents showed the opposite pattern of results. (Am J Addict 1998; 7:103–114)  相似文献   
995.
PURPOSE: This study was designed to evaluate a new anticolorectal carcinoma monoclonal antibody (1A3), conjugated with the bifunctional chelating agent N,N′-bis (2-hydroxybenzyl) 1 (4-bromoacetamidobenzyl) 1,2-ethylenediamine-N,N′-diacetic acid and labeled with indium-111, in a Phase I/II study involving 38 patients with localized or advanced colorectal cancer. METHODS: Patients were injected with indium-111-N,N′-bis(2-hydroxybenzyl) 1 (4-bromoacetamidobenzyl) 1,2-ethylenediamine-N, N′-diacetic acid-monoclonal antibody 1A3 (1–50 mg, 1–5 mCi) and imaged at two or three sessions one to five days later. Scintigraphic findings were compared with radiologic, pathologic, surgical, and other clinical findings to assess the accuracy of radioimmunoscintigraphy. RESULTS: At least one known tumor site was clearly defined by planar scintigraphy in 29 (76 percent) patients. Increased radioactivity was seen in 40 of 63 known tumor sites (37/43 abdominal-pelvic, 3/15 hepatic, and 0/5 pulmonary sites) without any apparent dose-related effects. Nineteen previously undetected sites were considered positive by imaging, and, of these, six were biopsy-proven tumor sites, four were probable tumor sites, three were definitely false positive sites, and six were probable false positive sites. Radioimmunoscintigraphy detected proven tumor in 15 of 16 patients with negative or equivocal computed tomography results. Of the 28 patients with rectosigmoid cancer, 25 (89 percent) had positive studies with 34 of 47 tumor sites showing definite uptake on the scintigrams. This included 3 of 9 hepatic metastases. The only adverse reaction occurred in one patient who developed transient hives. Human anti-mouse antibody responses occurred in approximately one-half of the patients injected with doses of 10 or 50 mg. CONCLUSION: This study shows that radioimmunoscintigraphy with this indium-111-labeled monoclonal antibody is safe, it can detect most nonhepatic abdominalpelvic tumors with a positive predictive value of 83 (44/ 53) percent, and it should prove to be useful, particularly in the diagnosis of recurrent rectal carcinoma.  相似文献   
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The growing problem of antibiotic resistant bacteria, along with a dearth of new antibiotics, has redirected attention to the search for alternative antimicrobial agents. Conjugated oligoelectrolytes (COEs) are an emerging class of antimicrobial agents which insert into bacterial cell membranes and are inhibitory against a range of Gram-positive and Gram-negative bacteria. In this study, the extent of COE resistance that Enterococcus faecalis could achieve was studied. Enterococci are able to grow in hostile environments and develop resistance to membrane targeting antibiotics such as daptomycin in clinical settings. Herein we expand our knowledge of the antimicrobial mechanism of action of COEs by developing COE-resistant strains of E. faecalis OG1RF. Evolution studies yielded strains with a moderate 4–16 fold increase in antimicrobial resistance relative to the wild type. The resistant isolates accumulated agent-specific mutations associated with the liaFSR operon, which is a cell envelope-associated stress-response sensing and regulating system. The COE resistant isolates displayed significantly altered membrane fatty acid composition. Subsequent, exogenous supplementation with single fatty acids, which were chosen based on those dominating the fatty acid profiles of the mutants, increased resistance of the wild-type E. faecalis to COEs. In combination, genetic, fatty acid, and uptake studies support the hypothesis that COEs function through insertion into and disruption of membranes and that the mechanism by which this occurs is specific to the disrupting agent. These results were validated by a series of biophysical experiments showing the tendency of COEs to accumulate in and perturb adapted membrane extracts. Collectively, the data support that COEs are promising antimicrobial agents for targeting E. faecalis, and that there is a high barrier to the emergence of severely resistant strains constrained by biological limits of membrane remodeling that can occur in E. faecalis.

COEs are emerging antimicrobials to combat drug resistant infections and to which bacteria develop only limited resistance.  相似文献   
999.
Purpose: To conduct a literature review identifying barriers and facilitators students with physical disabilities (SwD-P) may encounter in science and engineering (S&E) laboratories.

Method: Publications were identified from 1991 to 2015 in ERIC, web of science via web of knowledge, CINAHL, SCOPUS, IEEEXplore, engineering village, business source complete and PubMed databases using search terms and synonyms for accommodations, advanced manufacturing, additive manufacturing, assistive technology (AT), barriers, engineering, facilitators, instructor, laboratory, STEM education, science, students with disabilities and technology.

Results: Twenty-two of the 233 publications that met the review’s inclusion criteria were examined. Barriers and facilitators were grouped based on the international classification of functioning, disability and health framework (ICF). None of the studies directly found barriers or facilitators to SwD-P in science or engineering laboratories within postsecondary environments. The literature is not clear on the issues specifically related to SwD-P.

Conclusion: Given these findings, further research (e.g., surveys or interviews) should be conducted to identify more details to obtain more substantial information on the barriers that may prevent SwD-P from fully participating in S&E instructional laboratories.

  • Implications for Rehabilitation
  • Students with disabilities remain underrepresented going into STEM careers.

  • A need exist to help uncover barriers students with disabilities encounter in STEM laboratory.

  • Environments.

  • Accommodations and strategies that facilitate participation in STEM laboratory environments are promising for students with disabilities

  相似文献   
1000.
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