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Biomedical subjects

J Olsen

Publications and source records attributed to J Olsen.

At least 469 records · Page 26Linked to original sources
PubMed1984

Calculating risk ratios for spontaneous abortions: the problem of induced abortions.

The frequency of induced abortions varies greatly between and within populations, and the currently employed measures of the ratio of spontaneous abortions are distorted proportionally to the number of induced abortions. Corrections are therefore often necessary to avoid bias when risk ratios for spontaneous abortions are estimated. The potential magnitudes and direction of the bias associated with such risk ratios (under the null hypothesis) are given under certain model assumptions. Adjustment of the estimated risk ratios using an appropriate model for the given data is proposed, rather than using a fixed correction factor.

Abortion, Incomplete↗
PubMed1984

Occupational causes of laryngeal cancer.

In a case-control study of all new cases of laryngeal cancer in Denmark from 1980 to 1982, 326 cases and 1134 community selected controls participated. Questionnaires were used to obtain information on education, occupation, and number of occupational exposures as well as smoking and drinking habits. High risk ratios for laryngeal cancer were found for semiskilled and unskilled workers, workers exposed to dust, out of doors workers, drivers, and people working in the cement industries and port services. The study hypothesis was that exposure to chromium or nickel increases the incidence rate of laryngeal cancer. No support for this was found concerning chromium, but exposure to nickel had a statistically significant risk ratio of 1.7.

Chromium↗
PubMed1984

Screening for neuropsychiatric dysfunction. A latent structure analysis of two questionnaires.

Summing up information from interview or questionnaire data into a single number, an index, is not uncommon in social medical research, but the conceptual and mathematical background for this is too often neglected. The so-called "Rasch models" specify circumstances where a single index can be used. The necessary computer programs for doing this are now generally available (10, 11). Two often used questionnaires concerning neurotoxicity due to solvent exposure are tested using a Rasch model. None of the questionnaires were found to be in agreement with the necessary requirements for the model and no single number describes the respondent's degree of neuropsychiatric dysfunction. Much more work is needed before a suitable screening questionnaire is available.

Denmark↗
PubMed1984

Prevention of relocation of the aged in nursing homes.

In the period 1972-76 a descriptive and experimental socio-geriatric longitudinal investigation was carried out in the municipality of Odense. The aim of the experimental aspect was prevention of relocation of the aged in nursing homes. The practical work consisted in casefinding and social medical intervention by nurses experienced in geriatrics and in close contact with interdisciplinary groups. Emphasis was placed on familiarity with the structure of the social and health services, the provisions available, and with problem areas and deciding channels. Contact with the aged focused on gaining an overall impression of their situation, establishing mutual trust and cooperation. Aspects of the practical work that were emphasized were introduction to services, advice to the aged and personnel, coordination and follow-up for assessment of results. Twenty-three per cent of the age group 70-79 years and 51 per cent of the 80-years-olds and over were drawn randomly from the national person-register. In all, 4,128 persons were picked. They were then randomly divided into an intervention group and a control group. On December 31st, 1976, 154 persons from the intervention group and 189 from the control group had been relocated in nursing homes. The difference concerned mainly women over 80 years of age who had a statistically significant low relocation risk in the intervention group. Fewer elderly in the intervention group were relocated in nursing homes compared to controls after mid 74. Findings showed that on March 1st, 1983, duration of residence (survival) in nursing homes for the 343 persons who had taken up residency, was rather similar for both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1984

Testicular germ cell tumours in Denmark 1976-1980. Pathology of 1058 consecutive cases.

In the first five-year period of the Danish Testicular Carcinoma Study (DATECA) 1058 consecutive testicular germ cell tumours were examined. Of these, 554 were seminomas comprising 515 of typical type, 26 anaplastic and 13 spermatocytic; 497 were non-seminomas comprising 145 pure tumours and 352 mixed tumours of various types. Among the various subtypes of non-seminomas embryonal carcinoma (EC) was recorded in 87 per cent, endodermal sinus tumour (yolk sac tumour; EST) in 22 per cent, teratoma (T) in 55 per cent and choriocarcinoma (CC) in 17 per cent. Only very few tumours were pure EST or pure CC. Five tumours were recorded as 'others or uncertain'. The tumours were graded with regard to various histologic features. Moderate and severe necrosis, bleeding, and a large number of mitoses were significantly more frequent in non-seminomas. The presence of tumour tissue at the resection margin was also more frequent in non-seminomas. Tumours with a largest diameter of less than 2.5 cm had already caused metastases in 16 per cent of the seminomas and 29 per cent of the non-seminomas. Increasing size of the tumours was associated with increasing frequency of metastatic disease but this association was not directly proportional. Distribution of the various histologic types according to the stage of disease varied. Thus, 78 per cent of the seminomas presented in stage I while 54 per cent of the non-seminomas had localized disease. Anaplastic seminomas were distributed similarly to the non-seminomas while all spermatocytic seminomas, with one exception, were recorded as stage I. Of non-seminomatous subtypes pure EC was associated with the highest frequency of stage III, followed by mixed tumours containing CC components. Although the present series is large the heterogeneity of germ cell tumours demands further investigation of larger numbers to confirm some of the findings.

Adult↗
PubMed1984

Pulmonary blastoma: remission with chemotherapy.

A 59-year-old man with pulmonary blastoma, who had undergone right-sided pneumonectomy, had a relapse of the tumour 7 months later. Light-microscopic and ultrastructural studies were consistent with recurrence from the primary tumour. Cell kinetic studies revealed a high fraction of tumour cells in the S-phase. Complete remission of the recurrence was obtained within 16 days after initiation of combination chemotherapy consisting of CCNU, vincristine, VP-16 and cyclophosphamide.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1983

Transcriptional enhancer elements in the mouse immunoglobulin heavy chain locus.

Two regions in the immunoglobulin heavy chain locus were tested for their ability to enhance transcription of the SV40 early promoter. A portion of the intervening sequence between the heavy chain joining region (Jh) and the constant region of the mu chain (Cmu) can enhance transcription when it is cloned either 5' or 3' to the SV40 early promoter. The region between C alpha and the alpha switch site, which occurs 5' to the translocated c-myc oncogene in many murine plasmacytomas, does not show transcriptional enhancer activity in this assay.

Animals↗
PubMed1983

Tumor heterogeneity in lung cancer based on light microscopic features. A retrospective study of a consecutive series of 200 patients, treated surgically.

In order to study the problem of morphological tumor heterogeneity in lung cancer, 200 consecutive patients who had undergone surgery for a malignant lung tumor, were evaluated retrospectively with regard to morphological type. The tumor was classified morphologically in 187 patients, and 163 (87%) had a morphologically homogeneous tumor, based on light microscopic features and using the criteria recommended by the World Health Organization. The remaining 24 patients (13%) had a tumor with morphologic features of more than one cell type. It is concluded that morphological heterogeneity is a considerable problem in the classification of malignant lung tumors. This heterogeneity had been regarded as evidence of an endodermal origin of all major types of lung cancer. Future prospective studies will have to determine whether it has any therapeutic significance.

Adenocarcinoma↗
PubMed1983

Tobacco use, alcohol consumption and infertility.

An epidemiological study of the association between alcohol consumption, tobacco use and subfecundity is presented. Study subjects were recruited for a case-control study whose primary objective was to examine the association between occupational exposures and subfecundity. All 1069 women treated for infertility at Odense University Hospital during the period 1977-1980 were eligible for participation as cases. A control group was chosen consisting of 4305 women who had each delivered a healthy child with a gestational age over 258 days at the same hospital in the period 1977-1979. Data regarding occupational exposures and smoking and drinking habits were collected by mailed questionnaires. A response rate of 87% was obtained for both case and control groups. Use of tobacco and alcohol was significantly higher in cases compared to controls. A within-group comparison of alcohol consumption among controls with delayed conception of more than one year with controls who conceived their children within one year failed to demonstrate a statistical association. However, a statistically significant association was observed between smoking and delayed conception among controls. On the basis of this finding, along with further analyses, the authors suggest that the statistical association between smoking and subfecundity may be real and ought to be studied further. Moderate alcohol consumption does not seem to play a role in the development of subfecundity. The paper provides a systematic review of possible sources of bias in the study.

Alcohol Drinking↗
PubMed1983

Alcohol use, conception time, and birth weight.

Predictors of birth weight and birth length were studied using sociodemographic data collected from 2259 women who resided in Funen County, Denmark, and delivered a healthy child during the period 1978-9 at Odense University Hospital. Low birth weight was significantly related to tobacco use in the year of delivery (p less than 0.01), alcohol use during the same period (p less than 0.05), and a delay in conception of over six months (p less than 0.01). Smoking history and a delay in conception were also significantly associated with short birth length (p less than 0.01 and p less than 0.01, respectively).

Alcohol Drinking↗
PubMed1983

Analysis of pathological outcome of pregnancy.

A series of publications have demonstrated that women undergoing numerous pregnancies during their reproductive lives show considerably higher pregnancy order-specific abortion rates or perinatal mortality rates than women who have been pregnant less often. This gives rise to a statistical problem of control in connection with analytical epidemiology, especially since these differences are far greater than those expected for rates of abortion or perinatal mortality, for example between various occupational categories. The present article is concerned with statistical control problems of this nature. On the basis of computer simulations, the extent and direction of the bias which inadequate statistical control may bring about is calculated for situations in which the presumed deleterious effect is reflected in gravidity- and pregnancy order-specific relative risks.

Abortion, Spontaneous↗