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81.
BACKGROUND: The clinical efficacy and safety of doxycycline hyclate (8.5% w/w) delivered subgingivally in a biodegradable polymer (DH) was compared to placebo control (VC), oral hygiene (OH), and scaling and root planing (SRP) in 2 multi-center studies. METHODS: Each study entered 411 patients who demonstrated moderate to severe periodontitis. Patients had 2 or more quadrants each with a minimum of 4 qualifying pockets > or =5 mm that bled on probing. At least 2 of the pockets were > or =7 mm. Treatment with DH, VC, OH, or SRP was provided at baseline and again at month 4. Clinical parameters were recorded monthly. RESULTS: DH and SRP resulted in nearly identical clinical changes over time in both studies. Mean 9 month clinical attachment level gain (ALG) was 0.8 mm for the DH group and 0.7 mm for the SRP group in Study 1, and 0.8 mm (DH) and 0.9 mm (SRP) in Study 2. Mean probing depth (PD) reduction was 1.1 mm for the DH group and 0.9 mm for the SRP group in Study 1 and 1.3 mm for both groups in Study 2. Frequency distributions showed an ALG > or =2 mm in 29% of DH sites versus 27% of SRP sites in Study 1 and 31% of DH sites versus 34% of SRP sites in Study 2. PD reductions > or =2 mm were seen in 32% of DH sites versus 31% of SRP sites in Study 1 and 41% of DH sites versus 43% of SRP sites in Study 2. Comparisons between DH, VC, and OH treatment groups showed DH treatment to be statistically superior to VC and OH. Safety data demonstrated a benign safety profile with use of the DH product. CONCLUSIONS: Results of this trial demonstrate that treatment of periodontitis with subgingivally delivered doxycycline in a biodegradable polymer is equally effective as scaling and root planing and superior in effect to placebo control and oral hygiene in reducing the clinical signs of adult periodontitis over a 9-month period. This represents positive changes resulting from the use of subgingivally applied doxycycline as scaling and root planing was not limited regarding time of the procedure or use of local anesthesia.  相似文献   
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AIM: To investigate the association between attributes of subject location and incidence of clinically relevant levels of depressive symptoms (CRLDS), and to investigate whether an association remained after adjusting for individual-level factors using data from the population-based African American Health Study. METHODS: An 11-item depression scale (Center for Epidemiologic Studies Depression scale) was obtained at baseline and 3 years later through in-home evaluations. Census tract and block group deprivation indices were obtained from the 2000 census. The external appearance of the block where the subject lived was rated during sample enumeration, and the interior and exterior of the subject's dwelling were observed during the initial in-home interview. RESULTS: Of 998 subjects at baseline, 21.1% had CRLDS. Although 12.7% of the 672 people without CRLDS at baseline developed them by the 3-year follow-up, univariate and propensity-adjusted analyses revealed no association between the subject's location and the incidence of CRLDS. Sensitivity analyses confirmed the robustness of the findings. CONCLUSION: Despite other studies showing independent effects of neighbourhood characteristics on the prevalence of CRLDS, attributes of subject location are not independent contributors to the incidence of CRLDS in middle-aged urban African Americans.  相似文献   
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Four asymptomatic homosexual men reverted from positive to negative serologic results for the human immunodeficiency virus, type 1 (HIV-1) over 2.5 years, as shown by enzyme-linked immunosorbent assay (ELISA) and Western blot. Antibody bands in the Western blot from three men were undetectable 6 to 12 months after being positive; gradual fading of the number and intensity of bands was seen in the other man. No HIV-1-p24 antigenemia was detected; cryopreserved peripheral blood mononuclear cells were negative for HIV-1 by standard culture assay. Polymerase chain reaction (gene amplification) assays were done on peripheral blood mononuclear cells and showed the HIV-1 provirus in all subjects 6 to 18 months after the last positive antibody test. Serum specimens from each participant were genetically identical. Polymerase chain reaction showed that peripheral blood mononuclear cells from one subject at different times matched by HLA DNA typing. Clinical and laboratory features of these four men were similar to those of other seronegative subjects. Rare, asymptomatic persons seropositive for HIV-1 may not remain seropositive, but may remain latently infected with HIV-1.  相似文献   
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OBJECTIVE: The objectives of this work were to determine the prevalence of self-reported subclinical status for functional limitation and disability at baseline and assess their independent effects on the onset of functional limitation and disability 1-2 years later. METHODS: Nine hundred ninety-eight African American men and women 49-65 years old in St. Louis, MO, received comprehensive in-home evaluations at baseline and two annual telephone follow-ups. Outcome measures included walking a half-mile, climbing steps, stooping-crouching-kneeling, lifting or carrying 10 lbs., and doing heavy housework. RESULT: The baseline prevalence of subclinical status was 26.4% for walking a half-mile, 26.8% for climbing steps, 39.0% for stooping-crouching-kneeling, 29.1% for lifting or carrying 10 lbs., and 22.7% for doing heavy housework. The adjusted odds ratios for the task-specific subclinical status measure at baseline on developing difficulty 1-2 years later were 1.68 (p < .05) for walking a half-mile, 4.46 (p < .001) for climbing steps, 2.48 (p < .001) for stooping-crouching-kneeling, 2.51 (p < .001) for lifting or carrying 10 lbs., and 2.22 (p < .001) for doing heavy housework. Performance tests (tandem stand, chair stands, and preferred gait speed) did not have consistent independent effects on the onset of functional limitation or disability. CONCLUSION: The subclinical status measures were the main predictors of the onset of difficulty in all tasks and functions 1-2 years later. Interventions to reduce frailty should focus on self-reported subclinical status as an early warning system.  相似文献   
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Gorry PR  Zhang C  Wu S  Kunstman K  Trachtenberg E  Phair J  Wolinsky S  Gabuzda D 《Lancet》2002,359(9320):1832-1834
Entry of HIV-1 into a cell happens only after viral envelope glycoproteins have bound to CD4 and a chemokine receptor. Generally, macrophage-tropic strains use CCR5, and T cell-line-tropic strains use CXCR4 as coreceptors for virus entry. Dual-tropic viruses can use both CCR5 and CXCR4. About 1% of white people are homozygous for a non-functional CCR5 allele, containing a 32 base pair deletion (CCR5 Delta 32). We studied the persistence of dual-tropic HIV-1 in an individual homozygous for this deletion. Our results suggest that structural features of the HIV-1 envelope linked to CCR5 tropism could confer a selective advantage in vivo.  相似文献   
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Activity of daily living (ADL) and instrumental ADL (IADL) data from the 1989 National Long-Term Care Survey (NLTCS) are used to replicate two domains of functional status with a total of five dimensions among them. LISREL analysis of the 14,415 Black and White older adults obtained from the 1989 NLTCS screen replicates three ADL disability dimensions (basic, household, and advanced) with few modifications, except among Black males. Similarly, analysis of the 4,297 Black and White disabled older adults replicates five functional status dimensions (3 ADL disability dimensions plus lower- and upper-body functional limitation dimensions) with few modifications, except among Black males. These results suggest that improved understanding of functional status will occur from studies that take into consideration the differences between functional limitation and ADL disability. The results also indicate that further research on the validity of functional reports among Black males is needed.  相似文献   
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