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11.
Tyler D. Hartwell Willo Pequegnat Janet L. Moore Corette B. Parker Lisa C. Strader Annette M. Green Thomas C. Quinn Judith N. Wasserheit Jeffrey D. Klausner 《AIDS and behavior》2013,17(9):2893-2901
A human immunodeficiency virus (HIV) as a biological endpoint in HIV prevention trials may not be feasible, so investigators have used surrogate biological outcomes. In a multisite trial, the epidemiology of STIs may be different across sites and preclude using one STI as the outcome. This study explored using a composite STI outcome to address that problem. The combined biological endpoint was the incidence of any of six new STIs (chlamydia, gonorrhea, trichomonas (women only), syphilis, herpes simplex virus type 2 infection and HIV) during a 24-month follow up period. We investigated how a composite STI outcome would perform compared to single and dual STI outcomes under various conditions. We simulated outcomes for four populations that represented a wide range of sex and age distributions, and STI prevalences. The simulations demonstrated that a combined biologic outcome was superior to single and dual STI outcomes in assessing intervention effects in 82 % of the cases. A composite biological outcome was effective in detecting intervention effects and might allow more investigations to incorporate multiple biological outcomes in the assessment of behavioral intervention trials for HIV prevention. 相似文献
12.
McCoy DL Jones JM Anderson JW Harmon M Hartwell I Hameedi J 《Environmental toxicology and chemistry / SETAC》2002,21(8):1618-1627
The Delaware River-Bay system, USA, was the subject of a study by the National Oceanic and Atmospheric Administration that involved chemical and biological analyses, including the use of the biomarker P450 human reporter gene system (HRGS) to document the occurrence and distribution of cytochrome P450 (CYP) 1A1-inducing compounds. Sediment extracts from 81 locations along the Delaware River, Delaware Bay and immediate coastline were tested by utilizing HRGS as an inexpensive screening test, and were also analyzed for polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls, with selected stations analyzed for dioxins and furans. Benthic community degradation has been observed when benzo[a]pyrene equivalents (BaPEq) exceeded 60 microg/g. The average levels of BaPEq for the largely industrialized upper, middle, and lower regions of the Delaware River were 107, 62, and 5 microg/g, respectively, excluding outliers. Tributaries leading into river averaged 21 microg/g BaPEq, whereas the central Bay and open coast had relatively low values (2.0 and 0.5 microg/g BaPEq, respectively). The HRGS values were highly correlated with total PAHs measured in the same sediment samples (r2 = 0.81). Overall, contamination levels consistently decreased from the upper and middle river sites as collection locations progressed down through the lower river and bay to the coast. Thus, despite the relatively high contaminant load in the river system, Delaware Bay and the immediate coastline seem to have relatively low levels of contaminants, and, therefore, impacts on the benthic organisms in the bay and coast would not be expected from these findings. 相似文献
13.
Interventional uroradiologic procedures performed using gadodiamide as an alternative to iodinated contrast material 总被引:2,自引:0,他引:2
Spinosa DJ Angle JF Hagspiel KD Hartwell GD Jenkins AD Matsumoto AH 《Cardiovascular and interventional radiology》2000,23(1):72-75
Three patients with either a history of severe allergic reactions to iodinated contrast or marked renal insufficiency underwent interventional uroradiologic procedures using full-strength gadodiamide (Gd) as a contrast agent in place of iodinated contrast material. The procedures were percutaneous access for nephrostolithotomy, antegrade pyelography with placement of a nephroureteral stent, and a diagnostic nephrostogram with exchange of a nephroureteral stent. Gd was visualized fluoroscopically and produced satisfactory digital radiographs without allergic reaction or worsening renal function. Gd can be useful in guiding interventional uroradiologic procedures when iodinated contrast material is contraindicated. 相似文献
14.
Cytotoxic reduction and regeneration of murine marrow stem cells 总被引:1,自引:0,他引:1
P L Page P A Cook H M Greenberg B L Hartwell S H Robinson 《Experimental hematology》1983,11(3):202-211
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Green C Dinnes J Takeda A Shepherd J Hartwell D Cave C Payne E Cuthbertson BH 《Health technology assessment (Winchester, England)》2005,9(11):1-126, iii-iv
17.
OBJECTIVE: Suicidal thinking has been associated with cognitive rigidity, however, not all depressed patients contemplate suicide. Therefore, we hypothesized that compared with depressed subjects without suicidal ideation, depressed individuals with suicidal ideation would display poorer performance on measures of executive functioning that involve mental flexibility. METHOD: In-patients with a current major depressive episode who had no current suicidal ideation (n=28) were compared with those who had current suicidal ideation (n=5) on measures of executive functioning and two neurocognitive tests that predominantly assess non-frontal regions. RESULTS: Compared with non-suicidal depressed patients, depressed suicidal patients performed significantly worse on several measures of executive functioning after controlling for age, IQ, severity of depression and prior suicide attempts. The two groups performed similarly on tests that predominantly assess non-frontal regions. CONCLUSION: Depressed individuals contemplating suicide have cognitive rigidity, which does not appear to be a global brain dysfunction. Suicidal mental states may result from dysfunctional executive decision-making that is associated with the frontal lobe. 相似文献
18.
Hartwell JK Barnett RC Borgatti S 《Journal of health organization and management》2004,18(4-5):262-278
This paper examines medical managers' beliefs about the impact reduced-hour career paths for physicians has on organizational effectiveness. The findings of this exploratory inductive study of 17 medical managers at nine medical organizations in the Boston area suggest that managers believe the benefits of reduced-hour physicians (RHPs) far outweigh the disadvantages. However, many of their reasons appear to be exploitative of RHPs. In particular, managers believe that employing RHPs results in increased managerial control and that RHPs should: work more than they are compensated for; do a disproportionate share of the undesirable work; and remain extra flexible and available to the organization. An interpretation of the findings based on psychological contract theory is offered, and may help to illuminate other results reported in the literature, including some controversial findings that reduced-hour workers tend to have poor health outcomes. 相似文献
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