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31.
Vaginal specimens for culture of group B Streptococcus and anonymous questionnaires were obtained from 499 college women. Group B Streptococcus was isolated from 90 (18.0%) of the participants. A selective broth medium was more sensitive for detection of vaginal isolates (85 of 493; 17.2%) than was direct inoculation of blood agar plates (44 of 466; 9.4%). The most prevalent serotypes among the isolates were type III (37.9%) and type II (25.3%). Logit analysis identified four factors associated with a higher prevalence of vaginal colonization with group B Streptococcus. These organisms were isolated significantly more often from (1) women who had an intrauterine device (50% vs. 18.6%; P less than 0.001), (2) sexually experienced women (20% vs. 7.1%; P less than 0.02), (3) women studied during the first half of the menstrual cycle (26.5% vs. 14.5%; P less than 0.01), and (4) women 20 years of age or younger (21.4% vs. 14.8%; P less than 0.05). The prevalence of colonization with group B Streptococcus was not related to sexual practices, history of venereal disease, use of oral contraceptives, presence of gynecologic symptoms, use of antibiotics, race, educational level, marital status, or history of pregnancy.  相似文献   
32.
Patients with chronic obstructive pulmonary disease and a stable daytime PaO2 of < or = 55 mmHg (7.3 kPa) live longer and have a better quality of life if provided with long-term continuous oxygen therapy. It is reasonable to offer continuous oxygen therapy also to patients with other lung diseases that cause chronic hypoxaemia. Indications for supplemental oxygen therapy during exercise (ambulatory oxygen therapy) and sleep (nocturnal oxygen therapy) are less clear.  相似文献   
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Diet is one of the most important environmental factors influencing growth, body weight, survival, and age-related diseases of rodents in chronic studies. NIH-07 open formula diet was the selected diet for the NTP studies from 1980 to 1994. A new diet designated as NTP-2000 diet is the current diet for mice in the NTP studies beginning in 1994. This report is a summary of results of untreated control groups of B6C3F1 mice fed NTP-2000 or NIH-07 diet from several retrospective 2-year dosed-feed and inhalation studies for differences in growth, body weight, survival, and tumor incidences. The dosed-feed studies were conducted in 3 different facilities located in the United States, and all the inhalation studies were conducted in 1 facility. During dosed-feed studies, male and female mice housed in polycarbonate cages and fed the NTP-2000 diet had lower maximum body weights than those fed NIH-07 diet. However, during inhalation studies, mice housed in wire mesh cages and fed the NTP-2000 diet had higher maximum body weights than the mice fed NIH-07 diet. Survival was higher in groups fed NTP-2000 diet irrespective of sex, housing conditions, or body weight compared to the corresponding groups fed NIH-07 diet. Survival was higher in mice housed in polycarbonate cages irrespective of diet and sex compared to the respective sex and diet groups housed in wire mesh cages. During inhalation studies, survival of male and female mice fed NTP-2000 diet was higher than that of the groups fed NIH-07 diet, although the body weights of NTP-2000 diet groups were higher than those of the groups fed NIH-07 diet. When the NTP-2000 diet was used, male and female mice in dosed-feed studies and male mice in inhalation studies had markedly lower incidences of liver tumors than the corresponding groups fed NIH-07 diet. Significant decreases in the incidences of lung tumors were observed only in the male groups fed NTP-2000 diet during dosed-feed studies. These results suggest that body weight may not be the major contributing factor for mortality and liver tumors and that an interaction between diet and housing conditions appears to affect the growth, survival and tumor incidences of B6C3F1 mice.  相似文献   
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BACKGROUND: After markedly decreasing for 3 years, HIV/AIDS mortality declined only slightly in 1999. METHODS: The authors conducted a case-control study in four Florida urban public health HIV clinics to evaluate modifiable factors associated with HIV/AIDS mortality in a non-research setting. Structured chart review was conducted for 120 case-patients who died in 1999 and for 240 randomly selected control-patients. Risk factors associated with death in univariate analysis were entered into three conceptually related, matched logistic regression models. RESULTS: In the final multivariate model, homelessness (adjusted odds ratio [AOR], 9.98; 95% confidence interval [CI], 2.34-42.5), Medicaid insurance (AOR, 3.10; 95% CI, 1.43-6.74), having a documented adherence problem (AOR, 3.50; 95% CI, 1.64-7.47), injection drug use (AOR, 2.46; 95% CI, 1.11-5.43), non-specific liver failure (AOR, 76.9; 95% CI, 6.79-870.9), interrupted highly active antiretroviral therapy (HAART) secondary to side effects (AOR, 4.00; 95% CI, 1.46-10.9), and not receiving HAART (AOR, 2.62; 95% CI, 1.03-6.68) were independent predictors of mortality. CONCLUSIONS: In addition to medical and clinical indicators, several sociobehavioral-demographic factors remained important throughout the multivariate analysis. Improvement in care should include a focus on social circumstances of infected people. Special attention to the homeless, those with adherence problems, and those with liver disease is clearly indicated.  相似文献   
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OBJECTIVE: To systematically evaluate the quality of the development of guidelines for the management of chronic obstructive pulmonary disease (COPD). METHODOLOGY: MEDLINE and Excerpta Medica search for published guidelines, followed by independent evaluation by two reviewers, according to previously reported guideline development quality criteria, on a three-point scale. RESULTS: Five national COPD guidelines and two international COPD guidelines were retrieved. Reviewers demonstrated good inter-observer agreement in assessing the 10 combined guideline development criteria for the seven guidelines [kappa = 0.66]. Guidelines were only partly multi-disciplinary with little or no consumer input, were up to 48 pages in length, and often lacked practical summaries or management flow charts which could have facilitated retrieval of key management recommendations. Almost all the papers were based upon a consensus approach, rather than evidence based, and methods of resolution of differences of opinion were not stated. Patient outcomes, ethical and medico-legal implications were not addressed and six of the guidelines were sponsored directly or indirectly by a single drug company. CONCLUSIONS: In spite of COPD guidelines being reported by major national bodies for over a decade now, most fail to meet important criteria for high-quality guideline development, and evaluation of clinical impact remains undetermined.  相似文献   
40.

Objectives

To assess the prevalence of chronic respiratory conditions in metropolitan fire-fighters and to study associations between occupational exposure, use of respiratory protection and health-related quality of life (HRQoL) in fire-fighters with and without chronic respiratory conditions.

Methods

Cross-sectional cohort analysis: Respiratory symptoms, medical conditions, occupational tasks and exposures and consistency of using respiratory protection were inquired by questionnaire. The SF12®V2 Health Survey was used to measure physical (PCS-12) and mental (MCS-12) HRQoL. Fire-fighters were categorised in subgroups: asthma; COPD/emphysema/chronic bronchitis; no chronic respiratory conditions; and as being ‘not involved’ or ‘involved’ in fire-fighting tasks, the latter further categorised as ‘consistent’ or ‘inconsistent’ use of respiratory protection. PCS-12 and MCS-12 scores were compared between subgroups and categories using linear regression.

Results

Five hundred and seventy fire-fighters were analysed, 24 (4 %) fulfilled the criteria for asthma, 39 (7 %) for COPD/emphysema/chronic bronchitis. Fire-fighters with asthma were older than those in the other two subgroups and had been employed in the fire service longer. Respiratory subgroups did not differ in their involvement in fire-fighting tasks. Ninety-one percent of fire-fighters reported relevant occupational exposure in the past year. Mean PCS-12 scores for fire-fighters with no chronic respiratory conditions, asthma and COPD/emphysema/bronchitis were 52.0 (SD 6.9), 47.0 (8.5) and 48.1 (9.4). For PCS-12 (but not for MCS-12), interaction between having a chronic respiratory condition and inconsistent use of respiratory protection during fire knockdown was observed (p < 0.001).

Conclusions

Ten percent of metropolitan fire-fighters reported underlying chronic respiratory conditions. Presence of such a condition in combination with suboptimal protection from inhaled exposures may lead to poorer physical HRQoL.  相似文献   
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