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71.
Gary L. Davis MD 《Current hepatitis reports》2003,2(1):40-46
There has been considerable progress in the treatment of chronic hepatitis C since the first report that interferon (IFN)
monotherapy was effective in 1989. Early results were meager, with sustained loss of hepatitis C virus from blood in fewer
than 10% of cases. The combination of IFN with the oral nucleoside analogue ribavirin was a major breakthrough in clinical
hepatology; it led to dramatic increases in treatment responses, with 30% to 40% of patients clearing virus. Pegylated IFNs
that have prolonged activity and can be dosed once a week have now replaced standard IFNs. The combination of pegylated IFN
with ribavirin is the new standard of care; it causes sustained loss of virus in more than half of treated patients. Treatment
responses continue to be highly dependent on viral genotype. Patients with genotype 1, the most common type in the United
States, have a sustained clearance rate of 42% to 46%, whereas those with genotype 2 or 3 have a response rate approaching
80%. 相似文献
72.
Levodopa improves physical fatigue in Parkinson's disease: a double-blind, placebo-controlled, crossover study. 总被引:1,自引:0,他引:1
Jau-Shin Lou Greg Kearns Theodore Benice Barry Oken Gary Sexton John Nutt 《Movement disorders》2003,18(10):1108-1114
We quantitatively investigated the effect of carbidopa/levodopa (25/100) on physical fatigue during finger tapping and force generation in a double-blind, placebo-controlled crossover study. Parkinson's disease (PD) subjects were randomly assigned to carbidopa/levodopa or placebo for Visit 1 or 2 and participated in the following two studies: (1) Finger tapping. Twenty-five PD patients used their index fingers to strike two keys 20 cm apart on a musical instrument digital interface (MIDI) keyboard. The slopes of the regression line of dwell time and movement time were used to assess the rate of fatigue development. (2) Force generation. Twelve PD patients contracted the wrist extensors maximally to obtain a baseline maximum voluntary contraction (BMVC) force. Then they repetitively contracted the wrist extensors at 50% of the BMVC for 7 seconds and rested for 3 seconds. An interval maximum voluntary contraction (IMVC) was measured every three repetitions. Fatigue was defined as an IMVC of less than 60% of the BMVC. The slope of the regression line of IMVC was used to assess the rate of force decline. These two studies were repeated 1 hour after carbidopa/levodopa (25/100) or placebo. Subjects filled out the Multidimensional Fatigue Inventory (MFI) at the beginning of the first visit. Results showed that the slope of dwell time decreased with levodopa but not with placebo (P = 0.004). The rate of force decline also decreased with levodopa but not with placebo (P = 0.01). The subscores in the dimension of physical fatigue in the MFI did not correlate with the rate changes in dwell time or the rate changes in force decline. We concluded that (1) levodopa improves physical fatigue in finger tapping and force generation, (2) physical fatigue in Parkinson's disease is at least partially related to dopamine deficiency, and (3) the MFI measures different aspects of physical fatigue compared with those measured by finger tapping and force generation. 相似文献
73.
Claude W. Drake DDS MPH MS Ronald J. Hunt DDS MS James D. Beck PhD Gary G. Koch PhD 《Journal of public health dentistry》1994,54(1):24-30
In this longitudinal study of a random sample of North Carolinians over the age of 65 and living in their homes, 325 blacks and 280 whites were examined and interviewed 18 months after baseline examinations. Coronal caries incidence was greater among whites than blacks. The increment due to teeth becoming root fragments were similar for both races; however, there were more newly crowned teeth among whites. Newly crowned surfaces were not used as part of the caries increment in logistic regression models to investigate potential risk predictors. For blacks, caries development over the 18-month period was associated with a higher lactobacillus score and more coronal caries at baseline, more previously filled coronal surfaces, and lack of active membership in clubs or other groups. For whites, having no self-reported tooth sensitivity, having a lower socioeconomic index score, taking antihistamine medications at baseline, and having the perception of more problems after the age of 40 than before were all associated with the development of coronal caries. 相似文献
74.
75.
Gary N. Holland 《International ophthalmology》1994,18(3):163-165
The progressive outer retinal necrosis (PORN) syndrome is a recently described clinical variant of necrotizing herpetic retinopathy in patients with the acquired immunodeficiency syndrome (AIDS). It is caused by varicellazoster virus infection of the retina. Its course and clinical features distinguish it from the acute retinal necrosis syndrome and CMV retinopathy. Early disease is characterized by multifocal deep retinal opacification. Lesions rapidly coalesce and progress to total retinal necrosis over a short period of time. Despite aggressive therapy with intravenous antivirial drugs, prognosis is poor; disease progression and/or recurrence is common, and the majority of patients develop no light perception vision. Total retinal detachments are common. Prophylaxis against retinal detachment using laser retinopexy has not been useful in most cases. PORN syndrome is an uncommon, but devastating complication of AIDS. 相似文献
76.
Glenn A Pacio Paul Visintainer George Maguire Gary P Wormser John Raffalli Marisa A Montecalvo 《Infection control and hospital epidemiology》2003,24(4):246-250
OBJECTIVE: To determine the natural history of colonization with vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA), and resistant gram-negative bacilli among long-term-care facility (LTCF) residents. DESIGN: Observational cohort study. SETTING: A 355-bed LTCF with a ventilator unit and a subacute unit. PARTICIPANTS: Residents with colonization or infection with VRE, MRSA, or resistant gram-negative bacilli housed at the LTCF between December 1, 1999, and February 29, 2000. METHODS: Cultures of clinical and surveillance sites were performed at regular intervals. Charts were reviewed for clinical characteristics associated with clearance of colonization. Kaplan-Meier curves were constructed to analyze the number of days to clearance of colonization. RESULTS: Forty-nine residents had 65 episodes of colonization (27 VRE, 30 MRSA, and 8 resistant gram-negative bacilli). Eighteen (28%) of the episodes cleared. The clearance rate was 2.7 episodes per 1,000 person-days. Clearance occurred significantly more often with resistant gram-negative bacilli colonization compared with VRE or MRSA colonization (6 [75%] vs 12 [21%]; P = .007; relative risk, 4.17; 95% confidence interval, 1.26 to 11.8). There was a trend toward longer use of antimicrobial agents among residents with persistent colonization. Infections occurred most frequently with MRSA. The urinary tract was the most common site of infection. CONCLUSION: Among LTCF residents, colonization with resistant gram-negative bacilli is four times more likely to clear than colonization with VRE or MRSA. Performance of surveillance cultures at regular intervals may reduce the need for contact precautions for LTCF residents with resistant gram-negative bacilli colonization. 相似文献
77.
Revision chronic ear surgery. 总被引:6,自引:0,他引:6
David M Kaylie Edward K Gardner C Gary Jackson 《Otolaryngology--head and neck surgery》2006,134(3):443-450
OBJECTIVE: To report results of revision chronic ear surgery following guidelines of the American Academy of Otolaryngology-Head and Neck Surgery and to establish expectations for infection and cholesteatoma control and hearing outcomes. STUDY DESIGN: Retrospective case review of all patients who underwent revision chronic ear surgery from January 1, 1990 to December 31, 2000. Revision chronic ear surgery included canal wall up and canal wall down procedures with ossicular chain reconstruction performed as needed. Cholesteatoma control, hearing improvement, and closure of middle ear space are main outcome measures. SETTING: Tertiary referral center. RESULTS: Cholesteatoma recurrence rate was 57% at 1 year after surgery and 14% in patients with a minimum of a 5-year follow-up. Disease control was achieved in 96% of patients. Hearing was significantly improved in all surgical groups. Closure of the air-bone gap for revision partial ossicular replacement prosthesis cases (PORP) to less than 20 dB occurred in 50% of patients. Closure of the air-bone gap to within 30 dB for revision total ossicular replacement prosthesis (TORP) occurred in 60% of patients. Canal wall down status had a significant impact on hearing results after PORPs and TORPs; patients with intact canal walls had significantly better hearing results. Diagnosis of cholesteatoma significantly impacted hearing results for TORPs but not PORPS. CONCLUSIONS: Cholesteatoma control rates after revision surgery are similar to primary cases. Significant improvement in hearing can be expected after revision chronic ear surgery. Hearing results after a revision surgery that requires a PORP is worse than primary cases and is canal wall status dependent. Closure of the middle ear space and creation of a safe dry ear can be expected after revision chronic ear surgery. SIGNIFICANCE: This is a review of a large series of exclusively revision chronic ear surgery. EBM rating: C-4. 相似文献
78.
79.
Gary Gerber 《Optometry》2007,78(12):678-679
80.
What Is Sufficient Evidence for the Reliability and Validity of Patient-Reported Outcome Measures? 总被引:1,自引:0,他引:1