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This paper is of some historical interest. It describes an investigation to determine whether byssinosis occurred among workers in the waste cotton industry. It was undertaken in 1950 at the instigation of the Minister of National Insurance.

The materials used in the industry were (1) cotton that had been previously spun, and (2) waste material discarded during the preparations for spinning higher grades of yarn. A proportion of raw cotton was sometimes blended with the waste.

Twenty-two mills, representative of the industry, were surveyed. All the men in these mills, who were over 35 years of age and with at least 10 years' exposure to cotton dust, were seen. The investigations included a work history, a clinical examination, an assessment of effort dyspnoea, and a chest radiograph.

There were 140 men who had never been exposed to any dust hazard other than waste cotton. In this group were found seven (5%) men with disabling byssinosis and 35 (25%) men with lesser degrees of the same disease. There were also 15 (11%) men with bronchitis or emphysema without byssinosis.

Thus it was established that byssinosis did occur in the waste cotton industry. Insurance cover, under the National Insurance (Industrial Injuries) Act, 1946, was subsequently extended to workers in the waste cotton industry.

The survey provided no evidence that either the type of waste cotton processed or an admixture of raw cotton played a significant part in the aetiology or incidence of the disease.

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ObjectiveTo increase adult caregiver Tdap vaccination rates by offering Tdap vaccine during infant well-child visits.MethodsWe developed a pilot vaccine initiative wherein pediatricians offered Tdap vaccine to mothers and non-mother caregivers attending the 2-week well-child visit at a hospital-based clinic serving predominantly low-income families. We evaluated this initiative by asking mothers and caregivers to participate in a survey after the 2-week visit to determine self-reported Tdap vaccination status, demographics, and the source of their adult primary care.ResultsSeventy (69%) participants received the Tdap vaccine during the newborns’ 2-week well-child visit. Forty-six percent of the infants’ 152 adult household contacts were vaccinated through this initiative. Of those mothers and caregivers, more caregivers reported not having insurance (38% vs 15%, P < .001), and no routine medical care (23% vs 8%, P = .007).ConclusionsThrough this pilot initiative, we vaccinated 69% of mothers and non-mother caregivers presenting to the 2-week well-child visit. A large proportion of caregivers did not receive routine medical care or have insurance, which suggests that they otherwise may have poor access to the vaccine. Tdap vaccination in the pediatric office represents a substantial opportunity to increase vaccination rates.  相似文献   
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Mammographic screening of asymptomatic women has shown effectiveness in the reduction of breast cancer mortality. We are developing a computerized scheme for the detection of mammographic masses as an aid to radiologists in mammographic screening programs. Possible masses on digitized screen/film mammograms are initially identified using a nonlinear bilateral-subtraction technique, which is based on asymmetric density patterns occurring in corresponding portions of right and left mammograms. In this study, we analyze the characteristics of actual masses and nonmass detections to develop feature-analysis techniques with which to reduce the number of non-mass (ie, false-positive) detections. These feature-analysis techniques involve (1) the extraction of various features (such as area, contrast, circularity and border-distance based on the density and geometric information of masses in both processed, and original breast images), and (2) tests of the extracted features to reduce nonmass detections. Cumulative histograms of both actual-mass detections and nonmass detections are used to characterize extracted features and to determine the cutoff values used in the feature tests. The effectiveness of the feature-analysis techniques is evaluated in combination with the computerized detection scheme that uses the nonlinear bilateral-subtraction technique using free-response receiver operating characteristic analysis and 77 patient cases (308 mammograms). Results show that the feature-analysis techniques effectively improve the performance of the computerized detection scheme: about 35% false-positive detections were eliminated without loss in sensitivity when the feature-analysis techniques were used.  相似文献   
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