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131.
OBJECTIVES: This report describes the epidemiology of Haemophilus influenzae type b (Hib) invasive disease and oropharyngeal colonization among Navajo and White Mountain Apache children younger than 7 years in an era of widespread immunization. METHODS: We conducted active surveillance for invasive H influenzae disease from 1992 to 1999 and an oropharyngeal carriage study from 1997 to 1999. The predominant vaccine used was PedvaxHib. RESULTS: The average annual incidence of invasive Hib disease among children younger than 24 months was 22 cases per 100,000. Of 381 children younger than 7 years, only 1 (0.3%; 95% confidence interval = 0.0%, 1.3%) was colonized with Hib; 370 (97%) had received 2 or more doses of Hib conjugate vaccine. CONCLUSIONS: Among Navajo and White Mountain Apache children, Hib conjugate vaccines have led to a sustained reduction in invasive Hib disease and a reduction in oropharyngeal Hib carriage. The disease incidence among children younger than 24 months remains 20 times higher than in the general US population. Hib elimination will require additional characterization of colonization and disease in these high-risk populations.  相似文献   
132.
Children discriminated tactual dot patterns by size or form and by texture. Adding irrelevant, easy, correlated texture cues improved size and form discrimination while orthogonal irrelevant texture cues interfered. Facilitation and interference could be reversed by reversing dimensional difficulty, but were found also when the two dimensions were equally accurate, for both blindfolded sighted and for blind children. The theoretical implication with regard to age effects, and practical implications for using dot numerosity and dot density differences for Braille learning were discussed.  相似文献   
133.
A number of approaches have been developed in recent years to try effectively to engage service users in the process of planning and delivering health-care services. The consumerist methodology for the strategy described in this paper was designed to maximise staff involvement in capturing user views, in order to develop services at a district general hospital. This strategy--the Patient Care Development Programme (PCDP)--provides a framework for both staff and patient involvement in shaping and influencing the development of health-care services. Uses the findings from applying the strategy to modify care packages, roles, skills, layouts, protocols and procedures, in response to both the "shortfalls" and the service strengths that the patient's view uncovers. Discusses the results of an evaluation of the programme which has been replicated in another part of the UK. The PCDP now forms part of a clinical governance framework and is being used to develop multi-agency integrated care pathways.  相似文献   
134.
Seventy-five children with pyogenic liver abscess are reviewed and compared with 21 with amoebic liver abscess occurring within the same 13-year period (1974–1986). Both groups presented with a similar syndrome complex. Noted differences were age at presentation (pyogenic: mean age 4.5 years and amoebic: mean age 2 years), the association of dysentery in 43% of the amoebic group, and the 76% incidence of Ascaris infestation in the pyogenic group. Predisposing disease was uncommon. Diagnosis was often delayed, which led to 4 deaths in the pyogenic group (overall mortality 4%). Diagnosis was confirmed with ultrasound or nucleotide liver scan. Non-operative management with antibiotics and metronidazole was successful in 37% of pyogenic and 43% of amoebic abscesses. Laparotomy and open drainage was performed for clinical evidence of peritonitis or failure to improve within 48–72 h of commencing therapy. There was no operative mortality and little morbidity in both groups. Offprint requests to: S. Cywes  相似文献   
135.
Speech processing for cochlear implant prostheses   总被引:1,自引:0,他引:1  
The transformation of speech into electrical signals which can stimulate the auditory nerve in order to create hearing sensations that carry speech information depends on many factors. These include the limitations imposed by the current state-of-the-art in otological surgery, microelectronic and micromechanical technology, and knowledge of the functioning of the auditory system under both acoustic and electrical stimulation. Sufficient advances have been made in all these areas to enable several research centers to develop cochlear prostheses which give some hearing to certain totally deaf persons. The work of these centers towards the goal of full unaided speech perception via the prosthesis is examined and evaluated.  相似文献   
136.
PURPOSE: The effect of different phospholipids in stabilising the tear film was investigated to determine if particular polar head groups gave greater stability than others. METHODS: Purified phosphatidylcholine (PC), lysophosphatidylcholine (LPC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylserine (PS) and cardiolipin (CL) were used. These were applied to a model eye loaded with an artificial tear fluid and the tear break-up time (TBUT) was measured. Three variants of the artificial tear fluid were utilised: buffered saline alone; one with proteins and mucins; and one containing proteins, mucins and lipids. RESULTS: TBUT was improved by the presence of phospholipids. In particular, the best performance was with PI applied to artificial tear fluid containing proteins mucins and lipids. Use of buffered saline as the artificial tear fluid gave very short break-up times. CONCLUSION: Increase in tear film stability by phospholipids is probably not due to the charge carried by the polar head group, but more likely due to the charge distribution, and the presence of hydroxyl groups in the head group also tends to increase stability, possibly through specific interactions with proteins and mucins in the subphase.  相似文献   
137.
OBJECTIVES: To conduct a systematic review of the literature to describe and critically appraise studies reporting on the cost and/or effectiveness of interventions proposed to control the emergence of antimicrobial resistance (AMR). METHODS: The search for relevant studies encompassed consultation with world experts in AMR, and electronic bibliographic database search of: Medline (1960-2000); ISI (1981-2000); EMBASE (1988-2000); Grey Literature (1999-2000); Database of Reviews of Effectiveness (DARE) and the NHS Health Economic Evaluation Database (HEED) at York University's Centre for Reviews and Dissemination (CRD) (numerous years); OPAC (1975-2000); and the Cochrane Library Online (1990-2000). Only studies that concerned the effectiveness or cost-effectiveness of measures specifically designed to contain the emergence of AMR were reviewed. Standardised data extraction sheets, based on existing checklists for effectiveness and cost-effectiveness, were used to assess the validity of each study using the 'risk of bias criteria' suggested in the Cochrane Handbook. Only studies categorised as being at low or moderate risk of bias were reported fully. The reliability of the data review process was monitored by comparison of several, random, independent assessments by all authors. The mix of study methods (i.e. including studies based on non-randomised controlled trials) meant that formal meta-analysis was not possible, and thus a qualitative review was performed. RESULTS: In total, 43 studies were reviewed, with 21 classed as being at moderate or low risk of bias and therefore reported in the paper. These studies covered policies on: restricting the use of antimicrobials (five studies, suggesting that restriction policies can alter prescriber behaviour, although with limited evidence of subsequent effect on AMR); prescriber education, feedback and use of guidelines (six studies, with no clear conclusion); combination therapies (seven studies, showing the potential to lower drug-specific resistance, although for an indeterminate time period); vaccination (three studies showing cost/effectiveness). Most of these studies were: from the developed world, principally the USA; hospital-based, with few community level interventions; and concerned with effectiveness, not cost-effectiveness. CONCLUSIONS: Overall, there is an absence of good evidence concerning what is effective, and especially cost-effective, in reducing the emergence of AMR. However, in addition to more research concerning these forms of intervention, the paper highlights four specific areas for further investigation: validating intermediate or surrogate outcome measures to enable better use to be made of the literature on intermediate measures; development and evaluation of 'macro' strategies; research into specific aspects of AMR in developing countries; and empirical and methodological research concerning the economic evaluation of interventions.  相似文献   
138.
The inclusion of population health in the accreditation process is an important new direction in the Canadian healthcare system. While quality improvement is a concept familiar to most clinicians and administrators, the inclusion of population health may raise some questions: What is "population health?"; Should healthcare organizations be responsible for population health?; If so, what could they and should they be doing about it?; How would a healthcare organization achieve accreditation in population health?  相似文献   
139.
The current focus on staffing ratios as a means to assure appropriate care for patients ignores the very real differences among patients in their needs for nursing care. Implementing a system that identifies these needs provides a more accurate indication of staffing requirements. In addition, storing the raw data from the system at their most basic level provides opportunities for more extensive analyses and informed, data-driven decision-making related to resource allocation, performance improvement, and productivity enhancement.  相似文献   
140.
Sub-Saharan Africa is dominated by diseases of poverty. HIV/AIDS affects 28.5 out of a total of 600 million in the region. South Africa is the only country in sub-Saharan Africa in which implantable cardiovertor defibrillators (ICDs) are implanted (0.8/million in 2001). Only 3 of the 35 new ICDs were implanted in state-funded public hospitals. The pacemaker implantation rate for South Africa was 41/million in 2001. Approximately 20% of the population consume 56% of the health care expenditure, mainly funded by Medical Insurance. A tax-funded state health care system serves the rest of the population, but is concentrated on improving sanitation and primary health care. Diversion of funds from academic tertiary hospitals has reduced specialised services, particularly cardiology and cardiac surgery, and has resulted in an exodus of skilled personnel to the private sector. In the rest of sub-Saharan Africa, tertiary health care is mainly privately funded. Cardiology and cardiac surgery is not widely available. Many countries are crippled by debt and chronic local conflicts.Only one state hospital (Groote Schuur, Cape Town) provides an electrophysiology (EP) service including catheter ablation and ICD implantation, and training in EP, by two electrophysiologists. EP services are available privately in 3 centres. No EP service exists in the rest of sub-Saharan Africa.  相似文献   
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