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At least 1,513 records · Page 84Linked to original sources
PubMed2005

[Time-series analysis on road traffic injury in China].

OBJECTIVE: To establish the predictive models of road traffic injury(RTI) in China, to know the trend of RTI, and to provide the reference data for controlling RTI in China. METHODS: The China RTI data from 1951 to 2003 were collected, and in view of the problem of missing values, the method of intrapolation was adopted. The Box-Jenkins technique was used to analyze and predict the trend of RTI in China. Following the process for stationary time-series analysis, model identification, parameter estimation and model diagnosis, the predictive equation for RTI would be established. RESULTS: A series of predictive equations on RTI were finally established based on ARIMA models. The curve fitting is effective and the predictive data of RTI in 2003 are close to the true statistical data. CONCLUSION: The time-series model thus established proves to be of significant usefulness in RTI prediction.

Accidents, Traffic↗
PubMed2005

Calcipotriol monotherapy versus calcipotriol plus UVA1 versus calcipotriol plus narrow-band UVB in the treatment of psoriasis.

The purpose of this study was to evaluate the efficacy of calcipotriol ointment as monotherapy versus calcipotriol in combination with narrow-band ultraviolet (UV)-B or UVA1 phototherapy and to determine whether calcipotriol in combination with UVA1 is an alternative to calcipotriol with narrow-band UVB phototherapy. Forty-five patients with plaque psoriasis were divided into three treatment groups with no significant differences in Psoriasis Area and Severity Index (PASI) scores, mean age, sex or skin type. The total duration of the treatment was 3 months. Regarding PASI score, psoriasis regression was statistically significant between the groups. The response to UVA1 and narrow band UVB with calcipotriol was superior to calcipotriol monotherapy. UVA1 phototherapy with calcipotriol could be an alternative to narrow-band UVB phototherapy with calcipotriol.

Adult↗
PubMed2002

[Transcutaneous oxygen tension in hyperbaric condition as a predictor of ischaemia in non-healing diabetic foot ulcers].

UNLABELLED: The aim of the study was to evaluate the contribution of basal and modify transcutaneous oxygen tension measurement (TcpO2) to diagnosis of ischaemia and indication of angiography in non-healing diabetes foot ulcers: METHOD: 69 patients with non-healing diabetic ulcers localised on 76 legs underwent angiography (DSA) and basal and modify TcpO2 measurement after 100 % O2 exposition under normo- and hyperbaric conditions. CHARACTERISTIC OF PATIENTS: mean age 66 years (42 81), diabetes duration 14.3 years (1 - 36), glycated hemoglobin 7.9 % (+/-1,35). RESULTS: Clinically important angiographic findings were obtained in 80 % (61/76) all ulcers. Basal TcpO2 < or = = 30 mm Hg was detected in 82 % diabetic ulcers with positive DSA (sensitivity - SN). The specificity (SP), positive and negative predictive value (PPV, NPV), relative risk (RR) and accuracy (A) of test were 60 %, 89 %, 47 %, 1.7 and 78 % respectively. TcpO2 with hyperbaric 100 % O2 was determined as the strongest predictor of ischaemia by statistical logistic regression. SN (91%), SP (77%), PPV (94 %), NPV (67 %, RR (2.8) and A (88 %) of test were increased (cut off 270 mmHg). CONCLUSION: TcpO2 measurement contributes to the diagnosis of ischaemia in non-healing diabetic ulcers. Modify TcpO2 increases the test value.

Adult↗
PubMed2006

[Medico-genetic prediction of cerebral stroke risk].

A population family study including 1410 residents of Rostov region (280 families) was conducted. The study included questioning and analysis of medical records for the presence or absence of chronic diseases, including cardiovascular pathology, arterial hypertension, coronary heart disease, diabetes mellitus, and their complications, cerebral stroke (CS) and myocardial infarction, as well as the time of their occurrence. Statistic analysis included conventional descriptive statistics and regressive analysis, as well as a special part, population genetic analysis. The results showed that MI mortality was 21.4 times higher in the group of a high genotypic risk vs. the low risk group, 8.1 and 0.38%, respectively. The authors developed tools of MI risk prediction depending on hereditary burden, the use of which present a significant addition to the conventional system of phenotypic risk assessment. In order to adapt calculations to practical healthcare, the authors developed risk charts which allow MI risk assessment according to the magnitude of risk factors.

Catchment Area, Health↗
PubMedDate not supplied

Testing for sexually transmitted diseases among women of reproductive age: United States, 1988.

Approximately 13.3 million women aged 15-44--about 26 percent of all women of reproductive age who had ever had intercourse--were tested for sexually transmitted diseases (STDs) in the 12 months before the 1988 National Survey of Family Growth. Slightly over half of the women tested received the test as part of a family planning visit. Women who used clinics for family planning services were most likely to be tested--54 percent compared with 34 percent of women who used a private doctor for family planning and 16 percent of women who did not receive family planning services that year. The findings suggest that access to medical care, especially access to family planning clinics, has strong effects on a woman's chances of being screened for STDs, independent of her individual characteristics. The most important individual characteristic affecting the chance of being tested for an STD was race: About 47 percent of black, 27 percent of Hispanic, and 23 percent of white and other women were tested in the 12 months before the survey. Among groups with high-risk behaviors, only 34 percent of sexually experienced teenagers were screened for STDs in the past year, as were only 43 percent of women with a positive STD history and 32 percent of women with 10 or more lifetime partners.

Adolescent↗
PubMed1991

Modelling digit preference in fecundability studies.

Retrospective studies of fecundability, in which women are asked how many cycles they required to become pregnant, are often affected by problems of digit preference. A probability model for such digit preference is proposed in which misreporting favours 6 or 12 (and possibly also 3) cycles. It is assumed that in the absence of misreporting the number of cycles follows a beta-geometric distribution. The model is applied to two data sets, with clear-cut results: The inclusion of additional parameters to model the misreporting can lead to substantial improvements in fit, but causes little change to the estimated parameters of the underlying beta-geometric distribution. In some cases misreporting parameters may be regarded as nuisance parameters, while in others they may be of interest. We have found estimates of these parameters to vary between different categories of women in an interpretable manner. The models may also be used to estimate the percentage of couples in any study that misreport their conception waiting time.

Biometry↗
PubMed1991

Use of limiting-dilution type long-term marrow cultures in frequency analysis of marrow-repopulating and spleen colony-forming hematopoietic stem cells in the mouse.

We have developed an in vitro clonal assay of murine hematopoietic precursor cells that form spleen colonies (CFU-S day 12) or produce in vitro clonable progenitors in the marrow (MRA cells) of lethally irradiated mice. The assay is essentially a long-term bone marrow culture in microtiter wells containing marrow-derived stromal "feeders" depleted for hematopoietic activity by irradiation. To test the validity of the assay as a quantitative in vitro stem cell assay, a series of unsorted and physically sorted bone marrow cells were simultaneously assayed in vivo and overlaid on the feeders in a range of concentrations, while frequencies of cells forming hematopoietic clones (cobblestone area forming cells, CAFC) were calculated by means of Poisson statistics. Linear regression analysis of the data showed high correlations between the frequency of CFU-S day 12 and CAFC day 10, and between MRA cells and CAFC day 28. A majority of MRA activity and CAFC day 28 was separable from CFU-S day 12 and CAFC day 10. This correlation study validates the CAFC system as a clonal assay facilitation both the quantitative assessment of a series of subsets in the hematopoietic stem cell hierarchy and the study of single long-term repopulating cells in vitro.

Animals↗
PubMed1991

Effect of progestin therapy on cortical and trabecular bone: comparison with estrogen.

PURPOSE: To determine the effect of progestin therapy on bone mineral density in postmenopausal women and to compare its effects to those of estrogen. SUBJECTS AND METHODS: A prospective, randomized clinical trial was performed in 81 postmenopausal women aged 51.7 +/- 4.4 years (mean +/- SD). They were assigned to one of four groups: Provera 20 mg, Premarin 0.6 mg, Premarin 0.3 mg plus Provera 10 mg, and a placebo. In addition, all women received calcium supplementation, if necessary, to a calcium intake of 1,000 mg/day. We used single- and dual-photon absorpiometry, metacarpal radiogrammetry, and computed axial tomography to measure bone mineral density in the total skeleton, spine, radius, and metacarpal. RESULTS: Women receiving placebo lost bone at all sites (p less than 0.01). The Provera-treated group showed no change in total body calcium, but there were decreases in radial density (p less than 0.01), metacarpal cortex (p less than 0.01), and spine density (p less than 0.01). The Premarin-treated group had an increase in spine density and total body density (p less than 0.05), but a decrease in radial density (p less than 0.05). The Premarin-plus-Provera group showed no change in spine density, total body calcium, or radial density but had a decrease in metacarpal cortex (p less than 0.01). CONCLUSIONS: Compared to placebo, Provera reduced the rate of loss in cortical areas of the skeleton, but not in the spine, which contains more trabecular bone. In contrast, Premarin reduced the rate of loss in both cortical and trabecular areas of the skeleton. The low-dose combination of Premarin plus Provera was similar in its effect on bone to that of Premarin alone, suggesting that there may be a synergistic effect of this hormone combination on bone. Serum cholesterol levels decreased with Provera, Premarin, and the combination of both, whereas levels of serum triglycerides increased with Premarin treatment, decreased with the Provera regimen, and were unchanged with the combination therapy. Provera does not adversely affect the lipid profile.

Bone Density↗
PubMed1991

[Three-dimensional analysis on facial structures correlation of the facial aesthetics of Chinese].

The frontal facial moire photographs of 50 male and 50 female young adults with esthetic face strictly selected from Chinese population on the basis of the standard were taken and analysed three-dimensionally. It was found that not only significant correlation but also a statistical linear regressive equation existed between nose, lip and chin, between lip and chin, and between the width and the height of the face. So it is possible, on the basis of a known variable, to calculate another variable by means of the mathematical equation, which will provide quantitative variables for the orthognathic and the plastic surgery creating the esthetic face.

Adult↗
PubMed1991

Attributes of growth in the U.S. dental economy, 1950-89.

Previous research has established dentistry as a growth sector of the U.S. economy. This study examines the economic relationship between dentistry's growth and factors operating on the demand and supply sides of the dental market. Output, defined as real per capita dental expenditures, was hypothesized to be a function of consumer income, dental insurance and the supply of dentists. Data for the period 1950-89, were analyzed using a generalized least squares approach. The analysis supported the hypothesis, indicating a significant relationship between growth in the dental sector and economic market factors. The study concludes that dentistry's real growth since 1950 was: (1) induced by increases in demand, mainly attributable to insurance and to a lesser extent consumer incomes; and (2) supported by increases in supply. The findings provide support for the insurance hypothesis, which suggests that growth in dental insurance has had a significant impact on the dental economy in recent years.

Dental Health Services↗
PubMedDate not supplied

Consistency between reproductive preferences and behavior: the Sri Lankan experience.

Data collected in the 1982 Sri Lanka Contraceptive Prevalence Survey and the 1985 Sri Lanka Contraceptive Survey, a follow-up study, were used to examine the reliability of respondents' preferences for additional children. At the aggregate level, consistency was remarkable: In 1982, 47 percent of women said they wanted more children and in 1985, 49 percent had more, for a slight excess of actual over wanted fertility. Even though inconsistencies existed, at the individual level preferences were moderately predictive of subsequent behavior. Unwanted fertility was related not only to the demographic characteristics of the women but also to disagreement with their husbands on desired fertility. More of those who believed that their husbands wanted additional children than those who believed otherwise reported births in the follow-up period. Nonusers of contraception were over three times more likely than contraceptors using modern methods to have had an unwanted birth.

Adult↗
PubMedDate not supplied

Women's status and fertility: successive cross-sectional evidence from Tamil Nadu, India, 1970-80.

This study explores linkages between the status of women and fertility over time in Tamil Nadu, India, using sample survey data for currently married women aged 35-44 in 1970 and 1980. The effects of individual indicators of the status of women on fertility are decomposed into effects through each of the proximate variables, notably those affecting marriage duration, marital fertility, and contraception. There is considerable variation in the direction and magnitude of the relationships between the status indicators and fertility behavior and in the relationship to the underlying mechanisms at the two points in time. On balance, the evidence suggests improvements in the status of women come to exert an increasingly negative effect on fertility over the course of demographic transition.

Adult↗
PubMed1991

Air pollution and infant mortality from pneumonia in the Rio de Janeiro metropolitan area.

The authors report the results of an investigation into the possible association between air pollution and infant mortality from pneumonia in the Rio de Janeiro Metropolitan Area. This investigation employed multiple linear regression analysis (stepwise method) for infant mortality from pneumonia in 1980, including the study population's areas of residence, incomes, and pollution exposure as independent variables. With the income variable included in the regression, a statistically significant association was observed between the average annual level of particulates and infant mortality from pneumonia. While this finding should be accepted with caution, it does suggest a biological association between these variables. The authors' conclusion is that air quality indicators should be included in studies of acute respiratory infections in developing countries.

Air Pollution↗
PubMed1990

Independent prognostic value of laminin receptor expression in breast cancer survival.

We studied the possible prognostic role of laminin, estrogen (ER), and progesterone (PR) receptors and other pathological factors in relation to the disease-free interval and overall survival of female breast carcinoma patients. Multivariate analyses of clinical and pathological data with respect to the above survival time variables were performed by Cox regression. The statistical dependence of prognosis on ER, PR, and tumor size was based on the discriminant cutoff value that could best distinguish between survival curves. Axillary nodal status was the most significant independent factor in the prediction of both disease-free interval and overall survival of these patients. Use of the information on laminin receptor expression, PR concentration, tumor size, lymphocytic infiltrate, and tumor necrosis improved significantly the prediction of the risk of recurrence. Patients with tumors expressing laminin receptors had 40% less risk of recurrence (P = 0.0209) than those with no expression. On the other hand, four covariates were independently predictive of the risk of death: axillary nodal status, lymphocytic infiltrate, PR and ER concentration. There was a marginally significant (10% level) interaction between tumor size and lymphocytic infiltrate with respect to the prediction of the risk of recurrence. The above sets of variables were used to classify patients into risk groups for the prediction of recurrence and death.

Breast Neoplasms↗
PubMed1990

[Effect of the main factors of the phosphorus industry on the level and prognosis of morbidity with temporary disability].

It has been established that service record, occupation, sex, volume and quality of medical care influence the level of morbidity with temporary disability (TD) among workers of phosphorous factories under unfavourable and favourable labour conditions. Under rather favourable conditions the major impact on the reduction of morbidity with TD is made by the level of organization and quality of medical care provided for the workers. Under unfavourable labour conditions with simultaneous optimization of medical care for the workers, radical improvement of labour conditions and strict observance of technological production regime are required. By means of equation factors of multiple regression a statistical evaluation of the association between changes in morbidity with TD and trends of development in time of factor signs has been made. Prognostic estimations of morbidity level with TD and economic losses accordingly up to the year 2000 are determined.

Air Pollutants, Occupational↗
PubMed1989

[Blood viscosity is a chronic adjustment factor of arterial vasodilatation in humans].

Arteriolar geometry and blood viscosity, the two main factors determining vascular resistance were studied in 44 normotensive subjects and 106 hypertensive patients at the brachial circulation level. Vascular resistance was calculated as the ratio between mean blood pressure and mean arterial flow determined by pulsed Doppler. Blood viscosity at 240 sec-1 was measured with a coaxial cylinder viscometer: Compared to controls, hypertensive patients had higher vascular resistance (161 + 8 vs 124 + 9 mmHg.ml-1.sec, P less than 0.05) and higher viscosity (4.75 + 0.05 vs 4.50 + 0.07 mPasec, P less than 0.01). Vascular resistance was negatively correlated to blood viscosity both in control (r = 0.48; P less than 0.001) and in hypertensive (r - 0.39, P less than 0.001) groups. Arteriolar equivalent radius (a) calculated from Poiseuille's equation from the relation a = (8 mu/pi R) 1/4 was positively correlated to viscosity in the two regressions were statistically different (P less than 0.001) indicating that at higher viscosity levels, arteriolar equivalent radius had lesser increase in normotensive than in hypertensive groups. Thus chronic increase in blood viscosity is accompanied by a small vessels vasodilatory phenomenon which seems less efficient in normotensive than in hypertensive subjects and might contribute in part to the mechanisms of vascular resistance elevation observed in hypertension.

Adult↗
PubMedDate not supplied

Alpha 1-antitrypsin and lung function in cement workers.

The relationship between the serum concentration of alpha 1-antitrypsin (AAT), the concentration of dust at the workplace and lung function abnormalities was examined in 48 male workers occupationally exposed to cement dust. Measurements were performed in all subjects and included ventilatory volumes (FVC, FEV1), airway resistance (Raw), static lung volumes (RV, FRC, TLC), transfer factor for CO and AAT serum concentration. The relationship between lung function, smoking, respirable cement dust exposure, and AAT serum concentration was investigated by the method of multiple linear regression. A statistically significant correlation was observed between AAT blood concentration and respirable dust exposure. The contribution of respirable dust exposure to the description of AAT concentration was positive as was the contribution of Raw. The contributions of transfer CO, smoking and RV/TLC ratio were negative. All the variables considered accounted for approximately 30% of the total variability of the AAT concentration. To conclude, in cement workers the higher AAT serum concentration which is associated with a loss of lung function, and higher respirable cement dust concentration may be part of the defence mechanism against the potential proteolytic activity occurring in occupational dust exposure.

Airway Resistance↗