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991.
Why do GPs not implement evidence-based guidelines? A descriptive study   总被引:7,自引:0,他引:7  
BACKGROUND: There is an acknowledged gap between research findings and their implementation in clinical practice despite the existence of effective educational interventions. OBJECTIVES: Our aim was to identify what is impeding GPs from pursuing currently recognized good practice and implementing evidence-based guidelines in their management of hypertension in the elderly. METHOD: We carried out a qualitative study using semi-structured interviews conducted during focus group outreach visits to 34 GPs from nine practices in Merseyside involved in an educational programme designed to improve the management of hypertension in the elderly. RESULTS: Several barriers to the implementation of evidence-based guidelines in the management of hypertension in the elderly were identified. These included: doubts about the applicability of trial data to particular patients; the poor adherence of GPs to practice protocols; ageist attitudes of some GPs; the effect of time pressure and financial considerations making the subject a low priority; the absence of an effective computer system; and the absence of an educational mentor. All participants demonstrated a very positive attitude to practice-based education. They also welcomed external audit data, which compared their performance with that of other practices. Single-handed GPs were particularly enthusiastic about this approach as it provided them with the peer pressure they lacked. CONCLUSIONS: In order to bridge the gap between research and practice, educators need to address the various 'barriers to change' amongst practitioners.  相似文献   
992.
BACKGROUND: Estimates of the extent of musculoskeletal disorders (MSD) are usually based upon workers' compensation reports, although recent reports indicate that there may be widespread under-reporting of MSD. METHODS: An estimate of the incidence of arm and hand work-related MSD was made using capture-recapture analysis of the overlap between state workers' compensation reports and physician reports in Connecticut for 1995. The resulting estimate was compared to a population-based survey of MSD. RESULTS: There was very small overlap between the two state injury reporting systems: 6.7% of 793 reported workers' compensation cases, or 8% of 661 physician's reports. The estimate for MSD not captured by either system was 13,285, resulting in 14,686 (95% CI: 9,733-18,453) total reported and non-reported cases. This compares to an estimate of 13,775 cases (95% CI: 8,800-18,800) based on a phone survey. CONCLUSIONS: This analysis points to substantial under-reporting of MSD in Connecticut: estimates of unreported cases exceed those officially reported by a factor of 11:1. The findings have an important bearing on injury prevention programs and policy making.  相似文献   
993.
Monocyte chemoattractant protein-1 is a chemokine with potent monocyte activating and chemotactic effects. Monocyte chemoattractant protein-1 gene and protein expression is rapidly up-regulated in response to a variety of acute and chronic central nervous system disorders. The activation and recruitment of microglia and monocytes into areas of inflammation may play a critical role in the pathogenesis of acute brain injury. Monocyte chemoattractant protein-1 could be a pathophysiologically important mediator of the microglial and monocyte responses in the brain. Using a well-characterized model of acute excitotoxic brain injury in neonatal rats, experiments were designed to evaluate whether monocyte chemoattractant protein-1 plays a role in the progression of tissue damage. Direct co-administration of recombinant monocyte chemoattractant protein-1 with the excitotoxin N-methyl-D-aspartate exacerbated injury, both in the striatum and in the hippocampus, by 55% and 167%, respectively. Complementary experiments to determine the effect of functional inhibition of monocyte chemoattractant protein-1, using an anti-monocyte chemoattractant protein-1-neutralizing antibody, revealed that co-administration of the antibody with N-methyl-D-aspartate attenuated tissue injury in the striatum and hippocampus by 57% and 39%, respectively.Together, these data suggest that monocyte chemoattractant protein-1 is a mediator of acute excitotoxic brain injury in neonatal rats and that inflammatory mechanisms contribute significantly to the pathogenesis of acute neonatal brain injury. Whether chemokines are pathophysiologically relevant mediators of neuronal injury in human neonates remains to be determined.  相似文献   
994.
Damage to the hippocampus and medial temporal (MT) structures can lead to anterograde amnesia and may also impair latent learning, in which prior exposure to cues affects their subsequent associability. Normally, latent learning may reflect both representational and attentional mechanisms. Prior work has suggested that individuals with MT amnesia have specific deficits in representational processing; thus, latent learning that invokes primarily representational mechanisms might be especially impaired in MT amnesia. The current results provide preliminary confirmation of this prediction. In Experiment 1, a latent learning paradigm expected to invoke representational mechanisms was impaired in individuals with MT amnesia, whereas in Experiment 2, a paradigm expected to invoke other attentional mechanisms was spared in individuals with MT amnesia. This suggests the representational and attentional components of latent learning are dissociable and differentially affected in anterograde amnesia.  相似文献   
995.
The mechanisms that account for the strength loss after contraction-induced muscle injury remain controversial. We present data showing that (1) most of the early strength loss results from a failure of excitation-contraction coupling and (2) a slow loss of contractile protein in the days after injury prolongs the recovery time.  相似文献   
996.
997.
目的:研究5/6肾切除大鼠模型中p38MAPK磷酸化的动态表达情况。方法:82只雄性SD大鼠分为两组:5/6肾切除模型组72只,假手术对照组10只。模型组造模完成后,分别于肾切除早期(术后1/2h、1h、3h、6h、12h、1d、2d、4d)相应时间点处死,每组9只,假手术组于术后12h处死,称量各组体重及残余肾重,计算肥大指数;下腔静脉取血留取血清测定血肌酐(Scr)、尿素氮(BUN);以Western blotting免疫印迹法检测肾皮质磷酸化p38MAPK活性的表达情况;以病理光镜和电镜观察肾小球、肾小管及肾间质组织形态学及超微结构的变化。结果:模型组与对照组相比,肾脏呈代偿性肥大,肥大指数增高(P〈0.05),Scr和BUN升高(P均〈0.01)。免疫印迹法显示5/6肾切除术后1/2h、1h、3h、6h、12h磷酸化p38信号呈递增趋势,尤以12h信号最强,之后信号减弱,2d时几乎不可见,4d有较弱的信号,假手术组未见明显信号。光镜下,发现肾小球有轻度系膜细胞增生,基质增宽不明显,肾小管偶有轻度变性,间质偶有炎性细胞浸润。电镜下,偶见足突局灶融合。结论:5/6肾切除大鼠在造模完成后12h时磷酸化p38MAPK表达最强。  相似文献   
998.
BACKGROUND: In studies of the association between antibiotic-resistant infection and mortality, the importance of controlling for the underlying severity of illness is well recognized. However, it is unclear when the severity of illness should be assessed. Controlling for severity of illness on the day the culture specimen is obtained may underestimate the true association between resistance and mortality. OBJECTIVE: To assess the impact of calculating the Acute Physiology and Chronic Health Evaluation (APACHE) II score at different time points on the association between antimicrobial resistance and mortality. METHODS: We used an existing data set from a study that investigated the association between fluoroquinolone resistance and mortality. The APACHE II score was calculated at 3 time points: the day the culture specimen was obtained, 1 day before the culture specimen was obtained, and 2 days before the culture specimen was obtained. Separate multivariable models were constructed using the 3 different APACHE II scores. These models were compared qualitatively. RESULTS: Of 91 total subjects, 51 were infected with a fluoroquinolone-resistant strain and 40 with a fluoroquinolone-susceptible strain. The median APACHE II score for all subjects was 13 (95% confidence interval [CI], 11-15) when calculated on the day the culture specimen was obtained, 12 (95% CI, 11-13) when calculated 1 day before, and 11 (95% CI, 10-13) when calculated 2 days before the culture specimen was obtained. Of 91 subjects, 12 (13.2%) died. The 3 multivariable models (each with the APACHE II score calculated on a different day) were not substantively different; the adjusted odds ratio for the association between fluoroquinolone-resistant infection and mortality varied only from 1.38 to 1.65 in the 3 models. CONCLUSIONS: APACHE II scores calculated at different time points relative to obtainment of the culture specimen did not differ substantively. Furthermore, when the adjusted association between fluoroquinolone resistance and mortality was assessed, there were no substantive differences across multivariable models that incorporated APACHE II scores calculated at different time points.  相似文献   
999.
OBJECTIVE: To determine the incidence of central venous catheter (CVC)-associated bloodstream infection (CA-BSI) among patients admitted to general medical wards outside the intensive care unit (ICU). DESIGN: Prospective cohort study performed over a 13-month period, from April 1, 2002, through April 30, 2003. SETTING: Four selected general medical wards at Barnes-Jewish Hospital, a 1,250-bed teaching hospital in Saint Louis, Missouri. PATIENTS; All patients admitted to 4 general medical wards. RESULTS: A total of 7,337 catheter-days were observed during 33,174 patient-days. The device utilization ratio (defined as the number of catheter-days divided by the number of patient-days) was 0.22 overall and was similar among the 4 wards (0.21, 0.25, 0.19, and 0.24). Forty-two episodes of CA-BSI were identified (rate, 5.7 infections per 1,000 catheter-days). Twenty-four (57%) of the 42 cases of CA-BSI were caused by gram-positive bacteria: 10 isolates (24%) were coagulase-negative staphylococci, 10 (24%) were Enterococcus species, and 3 (7%) were Staphylococcus aureus. Gram-negative bacteria caused 7 infections (17%). Five CA-BSIs (12%) were caused by Candida albicans, and 5 infections (12%) had a polymicrobial etiology. Thirty-five patients (83%) with CA-BSI had nontunneled CVCs in place. CONCLUSIONS: Non-ICU medical wards in the study hospital had device utilization rates that were considerably lower than those of medical ICUs, but CA-BSI rates were similar to CA-BSI rates in medical ICUs in the United States. Studies of catheter utilization and on CVC insertion and care should be performed on medical wards. CA-BSI prevention strategies that have been used in ICUs should be studied on medical wards.  相似文献   
1000.
OBJECTIVE: In 2000, the rate of surgical site infections (SSIs) associated with pacemaker and implantable cardioverter-defibrillator (ICD) procedures performed in the cardiothoracic operating rooms of hospital A was 16% (19 of 116 procedures resulted in infections). This study investigates risks for SSI associated with these procedures in the cardiothoracic operating room. DESIGN: Unmatched 1 : 3 case-control study performed over a 12-month period among patients who had undergone implantation of a pacemaker and/or ICD. A standardized observation scrutinized infection control practices in the area where the procedures were performed. SETTING: The cardiothoracic operating rooms of hospital A, which belongs to a hospital consortium in the midwestern United States. PATIENTS: Patients with SSI were identified as case patients. Control patients were chosen from the group of uninfected patients who had procedures performed during the same period as case patients. RESULTS: A total of 19 SSIs associated with pacemaker and ICD procedures were retrospectively identified among the patients who underwent procedures in these cardiothoracic operating rooms. Culture samples were obtained from 7 patients; 2 yielded coagulase-negative Staphylococcus on culture, 2 yielded Staphylococcus aureus, 1 yielded Serratia marcescens, and 2 showed no growth. In the case-control study, age, race, sex, diabetes mellitus, smoking history, timing of antibiotic therapy, and hair removal did not differ significantly between case patients and control patients. Case patients were more likely to have an abdominal device in place (odds ratio [OR], 5.5 [95% confidence interval {CI}, 1.6-19.3]; P=.006) and less likely to have received a new implant (OR 0.3 [95% CI, 0.1-0.8]; P=.02) or to have had new leads placed (OR, 0.2 [95% CI, 0.1-0.6]; P=.003). CONCLUSIONS: Abdominal placement of implanted devices was associated with occurrence of an SSI after pacemaker and/or ICD procedures.  相似文献   
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