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PubMed2001

The effects of overbite on the maxillary and mandibular morphology.

The aim of this study was to investigate the differences in the maxillary and mandibular morphology related to the overbite. A total of 80 untreated subjects were divided into 4 groups with normal overbite, edge-to-edge bite, open bite, or deep bite and were compared with one another. Differences between the overbite groups and between genders were assessed by means of variance analysis and the least significant difference test. In addition, correlation coefficients between the overbite and other variables were calculated. The results showed that there are statistically significant differences in the maxillary and mandibular morphology among the overbite groups.

Adolescent↗
PubMed2003

The condylar asymmetry measurements in different skeletal patterns.

In the present study, condylar asymmetry measurements were investigated on the lateral cephalometric head radiographs and the panoramic radiographs of 72 subjects (36 males and 36 females), aged 12-16-years and having different skeletal patterns. The lateral cephalometric head radiographs were divided into three groups according to the ANB angle: ANB angles smaller than 1 degrees, between 1 degrees and 5 degrees, and larger than 5 degrees. In addition, each group was also divided into two subgroups according to sex. The effects on the ANB angle and sex on the condylar asymmetry measurement were investigated on the panoramic radiographs by means of variance analysis. It was observed that while condylar + ramus ratio measurement was affected by the change of ANB angle, the other measurements were not affected by it.

Adolescent↗
PubMed1975

[Prevention of postoperative thrombo-embolism using a new principle of drug treatment (author's transl)].

Slowing of venous return is, in addition to endothelial damage and hypercoagulability, one of the decisive factors in the development of thrombi. This is especially so in operated patients with loss of vessel tone caused by general anaesthesia. The radiofibrinogen test was used on a group of 106 patients to check whether the administration of dihydroergotamine, which produces vasoconstriction particularly of the venous channels, can bring about a reduction in the incidence of postoperative thrombo-embolism. There was a statistically (variance analysis) highly significant difference in the average thrombosis rate between treated (8.8%) and untreated (34.7%) patients. In patients especially at risk, the rate was more than three times as high in the untreated group (39.5% and 12.9%, respectively). In low-risk patients the rate actually dropped to zero (from 20%).

Adult↗
PubMed1995

[Peripheral occlusive arterial diseases: comparison of diagnostic value of MRA and DSA].

MATERIAL AND METHODS: In 59 patients with arterial flow disturbances 2-D inflow sequence of the abdominal and lower leg arteries were prospectively obtained on a 1.5 T MR-imager and were compared with additional DSA examinations. Supplementary Phase Contraste RSE ("Rapid Sequential Excitation") sequences were carried out in 29 patients. MRA and DSA angiograms were evaluated in random order by 4 readers using a questionnaire. The assessment of image quality were evaluated by variance analysis. Diagnostic performance of MRA and DSA was assessed by comparison of the readers' diagnostic assessments with reference diagnoses established by a radiologist and a vascular surgeon with full knowledge of all data concerning a patient. Image quality of inflow MRA was considered inferior to i.a. DSA (p < 0.001) and comparable with i.v. DSA (p = 0.1361). Image quality of RSE-MRA was inadequate (p < 0.001). Correspondingly, i.a. DSA was the superior and RSE-MRA the inferior imaging technique. The accuracy of inflow MRA in determining stenosis grade was 66% and that of RSE-MRA 59%.

Aged↗
PubMed2006

Sorptive behavior of sorgoleone in ultisol in two solvent systems and determination of its lipophilicity.

Sorgoleone (SGL) exuded by sorghum roots inhibits the development of some weeds. Due to its high hydrophobicity, it is expected that SGL presents low soil mobility and limited allelopathic activity in the field. This work aims to evaluate the sorptivity of sorgoleone in octanol-water and in soil under two solvent systems. The two solvent systems were methanol:water (60:40) (MeOH:H2O) and pure methanol (MeOH). These two solvent systems promote different conditions for SGL solubility. Treatments were arranged in a 2 x 6 factorial (solvent systems x equilibrium concentrations in the solution (EC)). For each solvent, the sorption was achieved by shaking 500 mg of soil with 10 ml of 0, 5, 10, 15, 25, 40, and 60 mg L-1 of SGL solution, during 24 h. After centrifugation, the supernatant was filtered and the SGL concentration was determined by high performance liquid chromatography (HPLC). Data of sorbed amount of SGL were submitted to variance analysis, using a hierarchic factorial model. The data of sorbed amount (x/m) and equilibrium concentration (C) were fitted to the linear (x/m = a + KdC) and to the Freundlich (x/m = KfC1/n) models. The isotherm obtained for the MeOH:H2O system presented linear shape, whereas for the MeOH system a two subsequent linear isotherm was fitted. Sorgoleone is a highly hydrophobic compound, presenting a log Kow of 6.1. The sorption of sorgoleone to the soil was very high. The organic environment stimulated the sorgoleone sorption to the soil.

Adsorption↗
PubMed2001

Mexico City physicians' awareness about cervical cancer prevention: implications for cancer screening.

BACKGROUND: In spite of an early cancer detection program (CCSP), Mexico has a mortality rate for cervical cancer of 16.5 per 100,000 women. METHOD: A cross-sectional study of 330 physicians at the Mexico City General Hospital evaluated their knowledge of the CCSP, etiology, diagnostic alternatives, and treatment guidelines. Variance analysis was the statistical procedure used. Replies to a questionnaire about cervical cancer prevention awareness were scored on a scale from 1 to 9. RESULTS: According to the awareness scale, the global average classification was 4.4, with 50% of the physicians scoring 4 or less. There was no difference in the CCSP knowledge scores of gynecologists (mean 4.92, 95% CI 4.2-5.3), oncologists (mean 4.85, 95% CI 4.3-5.5), pathologists (mean 5.23, 95% CI 4.9-5.6), and those in other specialties (mean 4.29, 95% CI 4.2-5.0), p > 0.05. Many respondents attributed CCSP's lack of effectiveness to public apathy (68.12%). CONCLUSIONS: The effectiveness of the CCSP can be improved by educating health professionals if this education is combined with elimination of obstacles to its use. More information is needed to justify revising how doctors are educated in terms of not only quality of the training but also the contents of pre- and postgraduate training programs.

Analysis of Variance↗
PubMed2003

A comparison of three fatigue measures in veterans with cancer.

Fatigue is a highly prevalent and distressing symptom in cancer patients. The purpose of this study was to assess the validity of three fatigue measures [the Brief Fatigue Inventory (BFI), the Functional Assessment of Cancer Therapy Fatigue Subscale (FACT-F), and the lack of energy item from the Memorial Symptom Assessment Scale Short Form (MSAS-SF)] and compare these measures in relation to broader quality-of-life (QOL) constructs and clinical factors in veteran cancer patients. One-hundred-eighty cancer patients completed the BFI, FACT-F, FACT-G, MSAS-SF, and the Zung depression scale with concurrent Karnofsky performance status (KPS), laboratory tests, and demographic data. The Cronbach alpha coefficient was from 0.93 to 0.94 for BFI fatigue scales and 0.94 for FACT-F. There were significant correlations between BFI subscales, FACT-F, and lack of energy from MSAS-SF (p < 0.0001). All three fatigue measures showed significant correlation with MSAS-SF symptom subscales (p < 0.0001), FACT-G subscales (p < 0.0001), depression (p < 0.0001), KPS (p < 0.0001), inpatient status (P < 0.0001), insomnia (p < 0.05), hemoglobin (p < 0.05), and albumin levels (p < 0.01). Distress from lack of energy discriminated among levels from the BFI, FACT-F, and FACT-G subscales and MSAS-SF subsclea by one-way of variance analysis. Patient responses to BFI, FACT-F, and the lack of energy item yielded similar information about broader QOL constructs and clinical factors. Single questions about lack of energy, or fatigue severity, may provide a simple and acceptable way to assess fatigue.

Adult↗
PubMed2006

Fully 4D motion-compensated reconstruction of cardiac SPECT images.

In this paper, we investigate the benefits of a spatiotemporal approach for reconstruction of image sequences. In the proposed approach, we introduce a temporal prior in the form of motion compensation to account for the statistical correlations among the frames in a sequence, and reconstruct all the frames collectively as a single function of space and time. The reconstruction algorithm is derived based on the maximum a posteriori estimate, for which the one-step late expectation-maximization algorithm is used. We demonstrated the method in our experiments using simulated single photon emission computed tomography (SPECT) cardiac perfusion images. The four-dimensional (4D) gated mathematical cardiac-torso phantom was used for simulation of gated SPECT perfusion imaging with Tc-99m-sestamibi. In addition to bias-variance analysis and time activity curves, we also used a channelized Hotelling observer to evaluate the detectability of perfusion defects in the reconstructed images. Our experimental results demonstrated that the incorporation of temporal regularization into image reconstruction could significantly improve the accuracy of cardiac images without causing any significant cross-frame blurring that may arise from the cardiac motion. This could lead to not only improved detection of perfusion defects, but also improved reconstruction of the heart wall which is important for functional assessment of the myocardium.

Algorithms↗
PubMed2001

Radiographic measurement of residual root thickness in premolars with post preparation.

A minimum thickness of 1 mm has been suggested for the residual root wall in post preparation. The objective of this paper is to evaluate the reliability of radiography when used to measure root thickness. In 106 upper first premolars with one and two root canals, post preparations were made with Peeso reamers to a depth in the root equal to the crown length. Bucco-palatal radiographs were taken of each tooth. The films were processed and projected with a magnification of x20. The smallest thickness of the mesial and distal walls of each root at the apical end of the preparation was measured and recorded. The teeth were then cut at the level of the measurement, and the smallest thickness of the proximal walls was measured using a microscope with a micrometric eyepiece. Fourteen percent of the teeth with one root canal and 27% of the teeth with two root canals could not be measured due to blurred radiographic contours. Variance analysis showed a highly significant difference (p < 0.001) when radiographic and anatomical measurements were compared. The radiograph showed greater thicknesses than were actually present and should not therefore be considered to be a reliable method for measuring residual thickness of tooth walls after post preparation.

Analysis of Variance↗
PubMed1993

Cyclosporine-induced stimulation of the renin-angiotensin system after liver and heart transplantation.

To analyze the status of the renin-angiotensin system in hypertensive transplant recipients on cyclosporine, we prospectively explored 21 cardiac (CTR: 52 +/- 8.2 yr) and 12 liver (LTR: 45 +/- 10 yr) transplant recipients on a normal salt diet with 19 normotensive controls in the same age range. Systolic and diastolic blood pressure was measured in the supine and standing positions. Renal function was assessed by serum creatinine values, and 24-hr urinary sodium and potassium excretion were recorded. Plasma renin activity (PRA), active renin, total renin, angiotensinogen, aldosterone, and cortisol plasma levels were simultaneously determined. Results were expressed as mean +/- SD, and between-group differences were compared using variance analysis. Supine blood pressure (+/- SD) was 158 +/- 15/103 +/- 8.4 in CTR and 155 +/- 21.4/102 +/- 11.7 mmHg in LTR. Serum creatinine was higher in CTR (159 +/- 52 mumol/L) than in LTR (117 +/- 24.7, P < 0.05) and values in both groups were above controls (83 +/- 14.1, P < 0.05). Urinary sodium excretion tended to be lower in transplant recipients (59 +/- 42 mmol/L) for CTR and 44 +/- 36.7 in LTR than in healthy controls (117 +/- 24.7 mmol/L). Supine and upright PRA values tended to be higher in hypertensive transplant recipients than in healthy volunteers, although not significantly. Supine active renin was significantly higher in CTR (47 +/- 42 pg/ml) and in LTR (44 +/- 29.8 pg/ml) than in normal subjects (17 +/- 4.8 pg/ml, P < 0.05). Total renin levels in CTR (supine: 716 +/- 357 pg/ml) and in LTR (supine: 647 +/- 365 pg/ml) were 3- to 4-fold higher than in controls (supine: 207 +/- 69 pg/ml) (P < 0.05), as were inactive renin levels (P < 0.01). Active renin was effectively correlated with PRA (P < 0.001) and with total renin (P < 0.001) in the supine and in the upright position. Plasma aldosterone was almost within the normal range in CTR and in LTR, and it did not correlate with PRA values. Plasma angiotensinogen levels were normal in LTR (1032 +/- 226 ng/ml) but were significantly lower in CTR (938 +/- 216 ng/ml, P < 0.05). Cortisol plasma levels were lower in both CTR (7 +/- 4.4 micrograms/L) and LTR (6 +/- 1.9 micrograms/L) than in healthy controls (11 +/- 4 micrograms/L, P < 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)

Aldosterone↗
PubMed1995

Prehospital resuscitation--outcome in an urban area.

All prehospital resuscitations performed by emergency physicians in the city of Bochum, Germany, were recorded and evaluated prospectively from 1 August 1989 to 30 September 1990. Initially successful cardiopulmonary resuscitation (CPR) was achieved in 33.8% (alive at admission), and definitive success in 10.4% (discharged alive). Of the patients who presented with cardiac arrest before the arrival of the emergency physician, 28.4% could be resuscitated initially and 7.6% survived definitively. In patients who suffered circulatory arrest on or after the arrival of the emergency physician, the initial success rate of CPR was 51.7%, and the definitive success rate 11.1%. Although the initial success rate was significantly more favourable, the definitive outcome did not differ statistically between these two groups. Two time periods were compared. During the first period of 5 months only one base with two ambulances staffed with emergency physicians was available. During the second period of 9 months an additional base with a physician-staffed ambulance was established. This reorganization resulted in the reduced call to arrival time falling from 8.5 +/- 2.4 min to 7.6 +/- 2.4 min (univariate variance analysis: f = 8.89, d.f. = 1.31, p < 0.01). This decrease, however did not improve either the initial or the definitive success of CPR. From these results we conclude that further improvement of prehospital resuscitation can only be achieved to a small extent by reducing the call to arrival time of ambulances staffed with emergency physicians. Improvement is more likely to be seen when immediate resuscitation is performed by bystanders present at the scene.

Adolescent↗
PubMed1993

A strategic approach to human resource planning in nursing.

In Britain, Canada and the USA, a chronic shortage of registered nurses has existed since World War II. This situation is predicted to become worse. Reviews both the general and nursing literature in human resource planning, and recommends a system which can be build up step by step and individualized for each nursing department. The core planning activities are a planning database, demand forecasting, supply forecasting, variance analysis and forecasting, and recruitment policies.

Analysis of Variance↗
PubMed2005

Sleep quality in hospitalized patients.

AIMS AND OBJECTIVES: The objective of this study was to evaluate and compare sleep quality of the hospitalized patients and matched healthy controls. BACKGROUND: Although the functions of sleep are not clearly understood, it is generally accepted that it is necessary for the maintenance of good health. Hospitalized patients' sleep may not be refreshing or restorative. The reasons for this can be categorized into three groups: environmental, physiological and psychological. DESIGN AND METHODS: This research was conducted at the Cumhuriyet University Hospital in Turkey. One hundred and fifty hospitalized patients (psychiatry = 50; orthopaedic + general surgery + cardiovascular surgery + urology = 50; internal medicine + chest diseases + infectious diseases + physical therapy and rehabilitation = 50) and 50 healthy controls constituted the sample. The researchers administered to the patient and control groups Sociodemographic Information Form and the Pittsburgh Sleep Quality Index. We compared sociodemographic and illness variables with sleep characteristics. The following statistical analyses were used in order to evaluate the data: variance analysis, Tukey HSD test, Student's t-test, Kruskall-Wallis test. RESULTS: We found that patients in psychiatric ward experienced worse sleep quality than the other patients, worse in female patients than male patients, and worse sleep characteristics in patients than controls. CONCLUSIONS: Health professionals must be educated about sleep and must provide intervention when needed. Relevance to clinical practice. The enhancing of sleep quality accelerates to the recovery from illness.

Adolescent↗
PubMed2006

Evidence-based clinical guidelines: a new system to better determine true strength of recommendation.

RATIONALE, AIMS AND OBJECTIVES: Clinical practice guidelines often grade the 'strength' of their recommendations according to the robustness of the supporting research evidence. The existing methodology does not allow the strength of recommendation (SOR) to be upgraded for recommendations for which randomized controlled trials are impractical or unethical. The purpose of this study was to develop a new method of determining SOR, incorporating both research evidence and expert opinion. METHODS: A Delphi technique was employed to produce 10 recommendations for the role of exercise therapy in the management of osteoarthritis of the hip or knee. The SOR for each recommendation was determined by the traditional method, closely linked to the category of research evidence found on a systematic literature search, and on a visual analogue scale (VAS). Recommendations were grouped A-D according to the traditional SOR allocated and the mean VAS calculated. Difference across the groups was assessed by one-way ANOVA variance analysis. RESULTS: Mean VAS scores for the traditional SOR groups A-D and one proposition which was 'not recommended' showed significant linearity on one-way ANOVA. However, certain recommendations which, for practical reasons, could not assessed in randomized controlled trials and therefore could not be recommended strongly by the traditional methodology, were allocated a strong recommendation by VAS. CONCLUSIONS: This new system of grading strength of SOR is less constrained than the traditional methodology and offers the advantage of allowing SOR for procedures which cannot be assessed in RCTs for practical or ethical reasons to be upgraded according to expert opinion.

Analysis of Variance↗
PubMed1981

Intellectual efficiency in manic-depressive patients treated with lithium. A control study.

A longitudinal study of 21 non-hospitalized manic-depressive subjects treated with lithium was carried out over a 3-year period: year 1 (Y1), year 2 (Y2), year 3 (Y3). A control group C of 21 subjects matched for age, sex and educational level was compared to Y1, Y2 and Y3 using the Cattell Intelligence Scale, the immediate memory recall test of numbers, the Code Test (WAIS), the 15-Word Test and the Benton Visual Retention Test. The vocabulary test of Binois and Pichot was first applied to C and Y1 to test the homogeneity of intellectual level between these two groups. A strategy of variance analysis followed by non-parametric Mann-Whitney and Wilcoxon tests was applied for statistical analysis of the results. Generally, except for the Cattell test, the patients presented lower scores than the control group. This decrease was not accentuated as time elapsed; the non-verbal were not affected more than the verbal tests. A clinical analysis was carried out relating the importance of the criteria "deterioration" to four other criteria: "age", "gravity and duration of illness ", "history of E.C.T." and "insufficient mood stabilization". The factor "gravity of the illness" was slightly more frequently associated with factor deterioration.

Adult↗
PubMed2004

Assessment of different methods for diagnosing dental caries in epidemiological surveys.

AIMS: The aims of the study were: (i) to assess different clinical diagnostic methods of dental caries during epidemiological surveys; (ii) to determine which combinations of methods and diagnostic adjuncts show the best performances in epidemiological surveys when compared with examinations performed in a traditional dental setting (standard); (iii) to evaluate the influence of including noncavitated (NC) lesions in dental caries estimation. METHODS: Forty 12-year-old children were divided into low and moderate caries prevalence groups. The individuals were submitted to 12 epidemiological examinations (in an outdoor setting), which combined three methods (blade, mirror and mirror + CPI (Community Periodontal Index) dental probe) with or without diagnostic adjuncts (previous dental brushing and dental drying). The last examination was performed in a traditional dental setting (standard examination). The unit of measure was the DMFS (decayed, missing and filled surfaces) index according to WHO criteria. The variance analysis, Dunnet's and Tukey's tests were applied. RESULTS: For the DMFS analysis, the visual/tactile method, with or without diagnostic adjuncts, was the best method for both groups, presenting a performance higher than 90% when compared with the standard examination, except for the examinations without previous dental brushing for the low caries prevalence group. Previous dental brushing was more relevant than dental drying (P = 0.0054). All of the epidemiological examinations underestimated the NC diagnosis even with the association of diagnostic adjuncts when compared with the standard examination. CONCLUSION: The visual-tactile (for both groups) and the visual (mirror) methods plus dental brushing (for the moderate group) are appropriate for diagnosing cavitated lesions, but not NC lesions.

Analysis of Variance↗