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1.
Spontaneous abortions and congenital malformations among women exposed to tetrachloroethylene in dry cleaning. 总被引:2,自引:1,他引:1
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P Kyyr?nen H Taskinen M L Lindbohm K Hemminki O P Heinonen 《Journal of epidemiology and community health》1989,43(4):346-351
STUDY OBJECTIVE: The aim of the study was to determine whether exposure to tetrachloroethylene during the first trimester of pregnancy has harmful effects on pregnancy outcome. DESIGN: The study used record linkage identification of cases and case-control comparison. SETTING: The study involved dry cleaner and laundry workers throughout Finland who had become pregnant during the study period. Controls were age matched but otherwise unselected women giving birth to normal babies in the study period. SUBJECTS: Cases were defined as women who had been treated for spontaneous abortion or had delivered a malformed child. Out of 5700 workers nearly half had been pregnant during the study period. One pregnancy only was randomly selected for study per worker, and the final study population was 247 women with spontaneous abortions and 33 with malformed infants. Three age matched controls were selected for each abortion case and five for each malformation case. MEASUREMENTS AND MAIN RESULTS: Three women out of four had worked in early pregnancy. Exposure information was collected from 1108 women by mailed questionnaires, with a 77% response, and was partly confirmed by biological monitoring data. Exposure to tetrachloroethylene was found to be significantly associated with spontaneous abortions (odds ratio 3.6, p less than 0.05). CONCLUSION: The findings, together with other available data, indicate that exposure of pregnant women to tetrachloroethylene needs to be minimised. 相似文献
2.
Risto Nikku Yrj N Nietosvaara Pentti E. Kallio Kari Aalto Jarl-Erik Michelsson 《Acta orthopaedica》1997,68(5):419-423
To assess whether initial surgery is beneficial for patients with primary dislocation of the patella, we carried out a prospective randomized study. Knee stability was examined under anesthesia, and associated injuries were excluded by diagnostic arthroscopy. 55 patients then had closed treatment and 70 patients were operated on with individually adjusted proximal realignment procedures.
Surgery gave no benefit based on 2 years of follow-up. The subjective result was better in the non-operative group in respect of mean Houghston VAS knee score (closed 90, operative 87), but similar in terms of the patient's own overall opinion and mean Lysholm II knee score. Recurrent instability episodes (redislocation or recurrent subluxation) occurred in 20 nonoperated and in 18 operated patients. Of these, 15 and 12, respectively, then suffered redislo-cations. Function was better after closed treatment. Serious complications occurred after surgery in 4 patients.
In conclusion, the recurrence of patellar dislocation may be more frequent than reported, whatever the form of treatment. Routine operative management cannot be recommended for primary dislocation of the patella. 相似文献
Surgery gave no benefit based on 2 years of follow-up. The subjective result was better in the non-operative group in respect of mean Houghston VAS knee score (closed 90, operative 87), but similar in terms of the patient's own overall opinion and mean Lysholm II knee score. Recurrent instability episodes (redislocation or recurrent subluxation) occurred in 20 nonoperated and in 18 operated patients. Of these, 15 and 12, respectively, then suffered redislo-cations. Function was better after closed treatment. Serious complications occurred after surgery in 4 patients.
In conclusion, the recurrence of patellar dislocation may be more frequent than reported, whatever the form of treatment. Routine operative management cannot be recommended for primary dislocation of the patella. 相似文献
3.
Ilkka Sinisaari Hannu Pätiälä Ole Böstman E. Antero Mäkelä Esa K. Partio Eero Hirvensalo Pertti Törmälä Pentti Rokkanen 《Journal of orthopaedic science》1997,2(2):88-92
Between November 1984 and January 1994 in our department, a total of 2500 patients were treated with totally absorbable internal
fixation devices. We studied these patients and analyzed results with regard to the volume of the absorbable implants and
the development of wound infection. Of the 2500 patients 2044 were trauma patients and 456 were operated on for orthopedic
disease. In 1466 patients treated with implants made of self-reinforced polyglycolic acid (SR-PGA) only, the patients who
developed wound infection had a higher implant volume (P=0.07) than those who did not; this difference was close to statistical significance. In the 446 patients who received only
implants made of self-reinforced poly-l-lactic acid (SR-PLLA), the 5 who developed wound infection had a mean implant volume more than three times that of the non-infected
patients (P=0.01). We found that in the patients treated with the earlier SR-PGA implants, which contained a green staining material,
there was no correlation between implant volume and incidence of wound infections. On the other hand, both the non-stained
SR-PGA implants, which have been in clinical use since 1989, and the SR-PLLA implants, seem to be more predictable in terms
of wound infections. We believe that this difference, is largely due to the lower level of tissue reactions with these newer
implants. 相似文献
4.
Evaluation of a new cellulose sponge-tipped swab for microbiological sampling: a laboratory and clinical investigation
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Osterblad M Järvinen H Lönnqvist K Huikko S Laippala P Viljanto J Arvilommi H Huovinen P 《Journal of clinical microbiology》2003,41(5):1894-1900
A new type of swab (Cellswab; Cellomeda, Turku, Finland), utilizing a highly absorbent cellulose viscose sponge material, was compared to some traditional swabs. The survival of 14 aerobic and 10 anaerobic and microaerophilic bacterial species in the Cellswab, two commercial swab transport systems (Copan, Brescia, Italy, and Orion Diagnostica, Espoo, Finland), and one Dacron swab (Technical Service Consultants Ltd. [TSC], Heywood, United Kingdom) was evaluated. Bacteria were suspended in broth, into which the swabs were dipped. The Cellswab absorbed 1.3 times more fluid and released 3.5 times more fluid upon plating than the other swabs. Aerobic bacteria were stored in dry tubes, the others in transport medium, at 4 degrees C and room temperature (RT), for up to 14 days. Swab samples were transferred to plates at 0, 1, 2, 4, 7, and 14 days. For 10 strains the Cellswab yielded > or =10% of the original CFU for longer than all the other swabs. In the clinical study, the ability of the Cellswab to detect beta-hemolytic streptococci from throat samples (n = 995) was compared to that of the TSC Dacron swab. The swabs performed equally, both when their samples were transferred to plates immediately and after storage for 1 day at 4 degrees C or RT. The changes in normal microbiota after storage were also similar. The Cellswab was found to perform at least as well as ordinary swabs. It was better at storing fastidious strains, and at keeping bacteria viable for long storage times; it might well be a useful replacement or complement to ordinary swabs. 相似文献
5.
Larsson J Persson C Tengvall P Lundqvist-Gustafsson H 《Journal of biomedical materials research. Part A》2004,68(3):448-457
Polymorphonuclear neutrophils (PMN) are among the first inflammatory cells to arrive at an implant interface, where they encounter with the foreign material and may produce reactive oxygen species (ROS). During the interaction between titanium and ROS, titanium-peroxy (Ti-peroxy) compounds may be formed. We used a Ti-peroxy gel, made from titanium and hydrogen peroxide, to study the effects of Ti-peroxy compounds on PMN. In the absence of serum, the Ti-peroxy gel decreased the oxidative response of PMN to yeast and PMA and reduced PMN apoptosis without inducing necrosis. These effects could not be ascribed to the release of hydrogen peroxide from the Ti-peroxy gel, because a steady-state hydrogen peroxide producing system failed to mimic the effects of the gel. The effects were similarly unaffected when PMN were preincubated with beta(2)-integrin antibodies, questioning the involvement of adhesion molecules. Nevertheless, when a filter was used to separate the Ti-peroxy gel from the cells, the gel effect on PMN life span was abolished, pointing to a contact-dependent mechanism. In the presence of serum, the Ti-peroxy gel had no effect on the PMN oxidative response and life span, but appeared rather inert. In summary, this study demonstrates that the Ti-peroxy gel has potentially anti-inflammatory properties through a combined peroxide and physical contact effect, supporting the notion that interactions between titanium and inflammatory cells are responsible for the good performance of titanium in vivo. 相似文献
6.
Parental age and risk of sporadic and familial cancer in offspring: implications for germ cell mutagenesis. 总被引:6,自引:0,他引:6
We used the nationwide Swedish Family-Cancer Database to analyze the effect of parental age on cancer in offspring at ages 15-53 years. We studied 13 cancer sites, including 37,877 people. Data on familial and sporadic cancers were analyzed separately. We adjusted for age of spouse, year of diagnosis, and birth order. Rate ratios (RRs) were calculated by Poisson regression. Maternal age was associated with sporadic melanoma and leukemia, causing a 30% excess if mothers were more than 40 years vs. less than 20 years of age. A marginal effect of about 10% of both maternal and paternal age was observed for sporadic breast cancer. Paternal age increased the RR of sporadic nervous system cancer by about 15%. Accumulation of chromosomal aberrations and mutations during the maturation of germ cells may be a mechanism for these findings. In familial cancers of colon, melanoma, and thyroid, higher age showed an apparent protective effect, which was also noted for sporadic cervical cancer and melanoma. The results argue against major age-induced mutagenic/carcinogenic effects on germ cells as well as against age-induced adverse cancer-related hormonal effects during pregnancy. Because two or more mutations are required for adult cancers, however, these cancers may be an insensitive indicator of germ cell mutagenesis. 相似文献
7.
Rebecca Troisi Nancy Potischman James M Roberts Gail Harger Nina Markovic Bernard Cole David Lykins Pentti Siiteri Robert N Hoover 《Cancer epidemiology, biomarkers & prevention》2003,12(5):452-456
Evidence suggests that adult cancer risk of hormonally related tumors may be influenced by the in utero environment, and most speculation on the biological mechanism has focused on the hormonal component. Epidemiological studies investigating the biological nature of pregnancy and maternal factors associated with offspring's cancer risk have relied on maternal hormone measurements. The degree to which maternal hormone levels represent the fetal environment, however, is not widely known. Pregnancy estrogen, androstenedione, testosterone, dehydroepiandrosterone (DHEA), and DHEA-sulfate concentrations were measured in maternal and mixed umbilical cord sera from 86 singleton pregnancies. Spearman correlations between maternal and cord hormone levels generally ranged between 0.2 and 0.3. The correlation was 0.26 for estriol, the estrogen of highest concentration in pregnancy, and 0.27 for estradiol, the most biologically active estrogen. The correlations between mother and offspring for the estrogens and DHEA appeared similar for males and females, whereas there was a suggestion that the maternal-umbilical cord correlations for other androgens varied in magnitude by fetal sex, and all correlations appeared higher in pregnancies lasting <38 weeks compared with longer gestational lengths, although these stratified findings may have been attributable to chance. These data show a moderate degree of correlation in hormone concentrations between the maternal and fetal circulation. Studies using maternal hormone concentrations as a proxy for the fetal environment should consider the misclassification resulting with the use of this marker. 相似文献
8.
Pekka Venesmaa Clinical Research Fellow Ulf-Håkan Stenman Consultant † Matti Forss Physicist Arto Leminen Consultant Pentti Lehtovirta Consultant Juhani Vartiainen Clinical Research Fellow Jorma Paavonen Associate Professor 《BJOG : an international journal of obstetrics and gynaecology》1998,105(5):508-511
Objective To evaluate the use of the pre-operative tumour-associated trypsin inhibitor (TATI) level and residual tumour size at primary surgery as a prognostic indicators for patients with Stage III epithelial ovarian cancer.
Design Retrospective cohort study.
Setting Department of Obstetrics and Gynaecology, University Hospital, Helsinki, Finland.
Participants Ninety-eight women with Stage III ovarian cancer.
Methods TATI was measured by radioimmunoassay from serum samples obtained within one week before surgery. A cutoff value of 22 μg/L was used. Multivariate analysis included pre-operative TATI level, age, histologic grade and histologic type. Mantel-Cox test was used for calculating statistical significance of differences in survival between groups.
Main outcome measures Cumulative five-year survival, pre-operative serum TATI level and residual tumour size.
Results Surgery was optimal (residual tumour size ≤ 2 cm) in 55 patients and suboptimal (residual tumour size > 2 cm) in 43. Pre-operative TATI level ≤ 22 μg/L predicted better prognosis both in patients with optimal and suboptimal surgery compared with patients with pre-operative TATI level > 22 μ/L. Patients with optimal surgery and a pre-operative TATI > 22 μg/L had a twofold relative risk of death compared with those with a pre-operative TATI ≤ 22 μg/L. The cumulative survival was less than three years for patients with suboptimal surgery and pre-operative TATI > 22 μg/L.
Conclusions Pre-operative serum TATI in combination with residual tumour size may be useful in stratifying patients with Stage III ovarian cancer into different categories in randomised treatment trials. 相似文献
Design Retrospective cohort study.
Setting Department of Obstetrics and Gynaecology, University Hospital, Helsinki, Finland.
Participants Ninety-eight women with Stage III ovarian cancer.
Methods TATI was measured by radioimmunoassay from serum samples obtained within one week before surgery. A cutoff value of 22 μg/L was used. Multivariate analysis included pre-operative TATI level, age, histologic grade and histologic type. Mantel-Cox test was used for calculating statistical significance of differences in survival between groups.
Main outcome measures Cumulative five-year survival, pre-operative serum TATI level and residual tumour size.
Results Surgery was optimal (residual tumour size ≤ 2 cm) in 55 patients and suboptimal (residual tumour size > 2 cm) in 43. Pre-operative TATI level ≤ 22 μg/L predicted better prognosis both in patients with optimal and suboptimal surgery compared with patients with pre-operative TATI level > 22 μ/L. Patients with optimal surgery and a pre-operative TATI > 22 μg/L had a twofold relative risk of death compared with those with a pre-operative TATI ≤ 22 μg/L. The cumulative survival was less than three years for patients with suboptimal surgery and pre-operative TATI > 22 μg/L.
Conclusions Pre-operative serum TATI in combination with residual tumour size may be useful in stratifying patients with Stage III ovarian cancer into different categories in randomised treatment trials. 相似文献
9.
10.
Jaana I. Halonen Jussi Vahtera Stephen Stansfeld Tarja Yli-Tuomi Paula Salo Jaana Pentti Mika Kivim?ki Timo Lanki 《Environmental health perspectives》2012,120(10):1391-1396
Background: Associations between traffic noise and sleep problems have been detected in experimental studies, but population-level evidence is scarce.Objectives: We studied the relationship between the levels of nighttime traffic noise and sleep disturbances and identified vulnerable population groups.Methods: Noise levels of nighttime–outdoor traffic were modeled based on the traffic intensities in the cities of Helsinki and Vantaa, Finland. In these cities, 7,019 public sector employees (81% women) responded to postal surveys on sleep and health. We linked modeled outdoor noise levels to the residences of the employees who responded to the postal survey. We used logistic regression models to estimate associations of noise levels with subjectively assessed duration of sleep and symptoms of insomnia (i.e., difficulties falling asleep, waking up frequently during the night, waking up too early in the morning, nonrestorative sleep). We also used stratified models to investigate the possibility of vulnerable subgroups.Results: For the total study population, exposure to levels of nighttime–outside (Lnight, outside) traffic noise > 55 dB was associated with any insomnia symptom ≥ 2 nights per week [odds ratio (OR) = 1.32; 95% confidence interval (CI): 1.05, 1.65]. Among participants with higher trait anxiety scores, which we hypothesized were a proxy for noise sensitivity, the ORs for any insomnia symptom at exposures to Lnight, outside traffic noises 50.1–55 dB and > 55 dB versus ≤ 45 dB were 1.34 (95% CI: 1.00, 1.80) and 1.61 (95% CI: 1.07, 2.42), respectively.Conclusions: Nighttime traffic noise levels > 50 dB Lnight, outside was associated with insomnia symptoms among persons with higher scores for trait anxiety. For the total study population, Lnight, outside > 55 dB was positively associated with any symptoms. 相似文献