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991.
We examined Escherichia coli and Klebsiella spp. from US hospitals for class 1 integrons. Of 320 isolates, 181 (57%) were positive; association of integrons with resistance varied by drug and organism. Thus, determining integron epidemiology will improve understanding of how antibacterial resistance determinants spread in the United States.  相似文献   
992.
Dengue prevention and 35 years of vector control in Singapore   总被引:2,自引:0,他引:2  
After a 15-year period of low incidence, dengue has reemerged in Singapore in the past decade. We identify potential causes of this resurgence. A combination of lowered herd immunity, virus transmission outside the home, an increase in the age of infection, and the adoption of a case-reactive approach to vector control contribute to the increased dengue incidence. Singapore's experience with dengue indicates that prevention efforts may not be sustainable. For renewed success, Singapore needs to return to a vector control program that is based on carefully collected entomologic and epidemiologic data. Singapore's taking on a leadership role in strengthening disease surveillance and control in Southeast Asia may also be useful in reducing virus importation.  相似文献   
993.

Objectives

A voluntary surveillance system was implemented in Catalonia (Spain) to ascertain the feasibility, incidence, and characteristics of occupational respiratory diseases and compare them with those of the compulsory official system.

Methods

In 2002, in collaboration with the Occupational and Thoracic Societies of Catalonia, occupational and chest physicians and other specialists were invited to report, on a bimonthly basis, newly diagnosed cases of occupational respiratory diseases. Information requested on each case included diagnosis, age, sex, place of residence, occupation, suspected agent, and physician''s opinion on the likelihood that the condition was work related. Compulsory official system data derived from statistics on work related diseases for possible disability benefits declared by insurance companies, which are responsible for declaring these diseases to the Autonomous Government of Catalonia.

Results

Of 142 physicians seeing patients with occupational respiratory diseases approached, 102 (74%) participated. Three hundred and fifty nine cases were reported, of which asthma (48.5%), asbestos related diseases (14.5%), and acute inhalations (12.8%) were the most common. Physicians rated 63% of suspected cases as highly likely, 28% as likely, and 8% as low likelihood. The most frequent suspected agents reported for asthma were isocyanates (15.5%), persulphates (12.1%), and cleaning products (8.6%). Mesothelioma (5.9%) was the most frequent diagnosis among asbestos related diseases. The number of acute inhalations reported was high, with metal industries (26%), cleaning services (22%), and chemical industries (13%) being the most frequently involved. The frequency of occupational respiratory diseases recorded by this voluntary surveillance system was four times higher than that reported by the compulsory official system.

Conclusions

The compulsory scheme for reporting occupational lung diseases is seriously underreporting in Catalonia. A surveillance programme based on voluntary reporting by physicians may provide better understanding of the incidence and characteristics of these diseases. Persulphates and cleaning products, besides isocyanates, were the most reported causes of occupational asthma. Metal industries and cleaning services were the occupations most frequently involved in acute inhalations with a remarkably high incidence in our register.  相似文献   
994.
PURPOSE: To clarify the association between use of widely distributed low-dose combined oral contraceptives (COCs) in China and the risk of stroke in order to decrease adverse reactions to COCs. METHODS: A prospective surveillance cohort study was undertaken in 25 towns in two counties in Jiangsu Province, China. Women (44,408 ) on hormonal contraceptives (HC) and 75,230 women with an intrauterine device (IUD) were followed up from July 1997 to June 2000 to study the difference in the incidence of stroke. RESULTS: The incidence of haemorrhagic stroke (age- and county-standardised rate) was far higher than that of ischaemic stroke (34.74 vs. 11.25 per 100,000 person years) among HC cohort. The relative risk (RR) of incidence of haemorrhagic stroke in the HC cohort (52 cases) was 2.72 times compared with that in the IUD cohort (23 cases). Compared with IUD users, the current users of HC had a higher RR of 4.20 (95%CI, 2.11-8.36) of haemorrhagic stroke, and still reached 2.17 (95%CI, 1.16-4.06) among past users after they stopped taking COCs for more than 10 years. The RR of haemorrhagic stroke was 3.09 (95%CI, 1.26-7.57) among women who had last used low-dose COCs during the previous 5 years. In women aged less than 45 years, compared to IUD users, the haemorrhagic stroke was strongly associated with current use of low-dose combined norethisterone pills, with RR being 19.06 (95%CI, 3.08-118.03). CONCLUSIONS: There is an increased risk of haemorrhagic stroke among Chinese users of long-term low-dose oral contraceptives, which appears to persist long after discontinuation.  相似文献   
995.
Continuous transepidermal drug collection (CTDC) has been proposed for use in assessing ethanol intake and in monitoring compliance with therapeutic regimens. Exploration of a theoretical basis for use of CTDC in these circumstances and for its use in assessing other aspects of drug disposition kinetics was undertaken. Effects of single and multicompartmental drug disposition models, single dose and multiple dose regimens, with regular and irregular doses and dosing intervals, and zero-order, first-order, and Michaelis-Menten excretion patterns were explored. First-order transepidermal drug transfer was assumed with and without back transfer from the collection device. These analyses suggest that the utility of CTDC is severely restricted when back transfer from the collection device is substantial. With back transfer minimized, CTDC may be a useful tool for assessing amount of drug exposure, compliance with therapeutic regimens, and relative bioavailability, but offers little advantage over discrete sampling of other body fluids in the study of other aspects of drug disposition kinetics.The views of the authors do not purport to reflect the positions of the Department of the Army or the Department of Defense. (Para. 4-3, AR 360-5).  相似文献   
996.
BACKGROUND: In many European countries, primary care surveillance networks play a role in public health surveillance. OBJECTIVES: To update an inventory of surveillance networks, to describe them and to report on their organization and function in a standardized way. To investigate whether and under what conditions their information can contribute to surveillance at a European level. METHODS: Surveillance networks were defined as 'A network of practices or community based primary care physicians who monitor one or more specific illness problems on a regular and continuing basis'. For the inventory questionnaires were sent out, followed by site visits to seven networks using a standardized audit checklist. RESULTS: We sent out 75 questionnaires and received 57 back (73% response rate), with 33 (58% of responders) fitting our selection criteria. National surveillance networks were identified in 11 countries. Many had an infectious disease surveillance component, particularly for influenza. Most were funded by the Ministry of Health, some by research funds. The median number of general practitioners was 120, comprising a stable group of general practitioners and covering a representative sample of the general population. The frequency of reporting varied from daily to annually, depending on the purpose of the network. CONCLUSIONS: A large number of primary care surveillance networks exist in Europe. Their value has been shown with the surveillance of influenza, but the challenge is now to extend their use to other diseases. When fulfilling identical minimal criteria they can provide comparable estimates of morbidity, ultimately leading to improved national and European surveillance.  相似文献   
997.
Liver function assessment in workers exposed to vinyl chloride   总被引:2,自引:0,他引:2  
Objective: To investigate liver function in vinyl chloride workers and assess its relation with current/past occupational exposure to vinyl chloride monomer (VCM). Methods: A medical examination including the execution of liver function tests (LFTs) and liver ultrasonography was executed in a group of 757 workers with a long-standing service in the production of VCM/polyvinylchloride (PVC). Cumulative and maximum VCM exposures were calculated. History of viral hepatitis and alcohol intake were carefully investigated. Regression analysis explored the association between abnormal LFTs and a group of possible determinants (VCM cumulative and maximum exposure, BMI, age, history of viral hepatitis, alcohol and triglyceride levels). Also, synergistic effect between VCM and a history of hepatitis was analysed, as well as the possible association between VCM exposure and aspartate aminotransferase/alanine amino transferase (AST/ALT) ratio >1. Distribution of abnormal LFTs was also assessed in relation to the results provided by liver ultrasonography. Results: The most frequently abnormal serum parameters were, in decreasing order: total cholesterol (27.3%), triglycerides (12.2%), total bilirubin (9.1%), gamma glutamil transpeptidase (GGT; 9.0%) and ALT (8.2%). The AST/ALT ratio >1 was present in 28.1% of workers. Abnormal LFTs were not found to be associated with current or past VCM exposure. High ALT resulted positively associated with BMI, AST with alcohol intake, GGT with alcohol intake and triglycerides. No synergistic effect on LFTs of exposure to VCM and a history of hepatitis was observed. The AST/ALT ratio >1 was not found to be associated with VCM exposure. The prevalence of abnormal LFTs was higher in case of liver steatosis (ALT) or periportal fibrosis (GGT), but not in case of pure hepatomegaly, as documented by ultrasonography. Conclusions: Liver function assessment only including LFTs is not able to detect VCM-induced liver damage, but reveals alterations due to non-occupational factors, such as dietary and/or metabolic disfunctions. The LFTs are however of importance to detect conditions that could recommend avoidance of exposure to VCM and are useful for medical counselling and health promotion purposes.  相似文献   
998.
BACKGROUND: Child obesity has unclear determinants and consequences. A precautionary approach requires best-guess interventions and large-scale surveillance. This study was to determine the current measurement activities and the information systems required for child obesity surveillance. METHODS: DESIGN: Questionnaire-based surveys. SETTING: Primary Care Trusts (PCTs) in United Kingdom. PARTICIPANTS: Two hundred and forty-seven (82%) PCTs in 2004 and 240 (79%) in 2006. MAIN MEASURES: Children's ages at which height and weight are routinely measured, the type of personnel taking the measurements, arrangements for recording data, information systems and uses of the data. RESULTS: PCTs measure height/length and weight most commonly at 6 weeks (74%) and 5 years (74%)-also at 6-12 months (58%), 1.5-2.5 years (50%), 2.5-4 years (40%), 11 years (18%) and 7 years (11%). Seventy-seven per cent of PCTs transferred the measurements to a database-26 different information systems were named. Six per cent of PCTs in 2004, rising to 34% in 2006, used the data to produce public health reports. CONCLUSIONS: Body mass index (BMI) surveillance requires new arrangements in 25% of PCTs at school entry and 80% at transfer to senior school. Important aspects of child obesity surveillance not yet addressed are pre-school measurement, longitudinal assessment and the public health requirements of (child) electronic health records.  相似文献   
999.
1000.
BACKGROUND: In 2004, The Victorian Hospital Acquired Infection Surveillance System Coordinating Centre established a smaller hospital (<100 beds) surveillance programme that included an optional 'surgical antibiotic prophylaxis' (SAP) module. Appropriate SAP is believed to be one of the most effective strategies to reduce surgical site infections after certain surgical procedures. METHODS: Trained infection control nurses in the participating hospitals were asked to collect SAP data for the first 50 consecutive procedures that could be classified into 1 of 12 surgical groups. The choice, timing and duration of antibiotics were compared against the Australian Therapeutic Antibiotic version 12 Guidelines and the US National Surgical Infection Prevention Project Advisory Statement. RESULTS: Fifty-one of the 87 smaller hospitals that participated in the surveillance programme of The Victorian Hospital Acquired Infection Surveillance System Coordinating Centre carried out surgery. Over 20 months, 25 of these hospitals contributed data on 1872 procedures. Antibiotic choice, timing and duration were 52.6, 54.7 and 76.1%, respectively, concordant with published recommendations. For antibiotic choice in five surgical groups (appendectomy, colon surgery, gastric surgery and abdominal and vaginal hysterectomies), less than half of the procedures were concordant with the Australian Therapeutic Antibiotic Guidelines. CONCLUSIONS: Substantial opportunities exist in smaller hospitals to improve compliance with published SAP recommendations. Further studies are required to determine the reasons for poor compliance with these recommendations.  相似文献   
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