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At least 451 records · Page 25Linked to original sources
PubMed1998

The use of confluence stages does not decrease the overall variability in primary human osteoblasts but can give additional information on differentiation in vitro.

Primary cultures of human osteoblast-like cells are frequently used to study osteoblast function. Due to inhomogeneous growth of primary osteoblasts in culture, it is of interest if the use of confluence stages for analysis would reduce the overall variability. Consequently, we have tested the influence of degree of confluence and passage number on the growth and differentiation of human primary osteoblast-like cells. Phenotypic features of primary human osteoblast-like cells were compared at four successive cell densities defined as stage of confluence I (50%), stage II (75%), stage III (100%) and stage IV (5 days post confluence). The stability of the system was also tested by comparing these observations obtained using cells from the 2nd and 4th passages. As a sign for further differentiation, the number of AP-positive cells increased with a decrease in proliferation. The secretion of procollagen-I decreased to 50% during culture while procollagen I mRNA doubled from proliferation to confluence. A constant activity of alkaline phosphatase, procollagen-I secretion and procollagen I gene expression over passages was seen together with a decrease in growth. The paper introduces a potential model of osteoblastic differentiation in vitro for human primary osteoblast-like cells. We were able to show an increasing differentiation with a decrease in proliferation and the stability of this differentiation behaviour over cell passages in this model, but we were not able to reduce the overall variability.

Adult↗
PubMed2000

Differential influence of nucleoside analog-resistance mutations K65R and L74V on the overall mutation rate and error specificity of human immunodeficiency virus type 1 reverse transcriptase.

Human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) variants with the K65R or L74V substitution display resistance to several nucleoside analogs. An in vitro dNTP exclusion assay revealed an increased fidelity for K65R RT compared with wild-type RT, but little change for L74V RT. When the forward mutation rates were measured via a gap-filling assay, the K65R variant displayed an 8-fold decrease in the overall mutation rate (1.0 x 10(-3) versus 8.6 x 10(-3) for wild-type HIV-1 RT), whereas the rate for the L74V variant was closer to that for wild-type RT (5.0 x 10(-3)). The increase in overall fidelity observed for K65R RT is the largest reported for any drug-resistant HIV-1 RT variant. Nucleotide sequence analysis of lacZalpha mutants generated by variant RTs indicated that K65R RT displays uniform reduction in most types of errors, whereas L74V RT does not. Modeling the substitutions into the x-ray structure of the ternary complex revealed that the major influence of Leu(74) in stabilizing the templating base is unaffected by Val substitution, whereas the K65R substitution appears to increase the stringency of dNTP binding. It is speculated that the increased fidelity of K65R RT is due to an altered interaction with the dNTP substrate.

Anti-HIV Agents↗
PubMed2003

Consumption of bakery products, sweetened soft drinks and yogurt among children aged 6-7 years: association with nutrient intake and overall diet quality.

The present study tests the hypothesis that higher consumption of bakery products, sweetened soft drinks and yogurt is associated with higher intake of energy, saturated fats, sugars and worse overall diet quality among Spanish children. This is a cross-sectional study covering 1112 children aged 6.0-7.0 years in four Spanish cities. Nutrient and food intake were obtained through a food-frequency questionnaire, and overall diet quality calculated using the healthy-eating index (HEI) developed by Kennedy et al. (1995). Standardized methods were used to measure anthropometric variables. Associations of interest were summarized as the difference in nutrient and food consumption between the value of the fifth and the first quintile of consumption (dq) of bakery products, sweetened soft drinks or yogurt, adjusted for energy intake and BMI. Bakery products, sweetened soft drinks and yogurt supplied 15.5, 1.0 and 5.6 % energy intake respectively. Higher consumption of these three foods was associated with greater energy intake (P<0.001), but not with higher BMI. Consumption of bakery products was associated with the proportion of energy derived from intake of total carbohydrates (dq 4.5 %, P<0.001) and sugars (dq 2 %, P<0.001), but did not show association with the HEI. Consumption of sweetened soft drinks was associated with a lower consumption of milk (dq -88 ml, P<0.001) and Ca (dq -175 mg/d, P<0.001), and worse HEI (dq -2, P<0.01). Consumption of yogurt, while associated with higher energy intake from saturated fats (dq 1.77 %, P<0.001) and sugars (dq 2.02 %, P<0.001), showed no association with the HEI. Differences in the intake of nutrients and foods across quintiles of consumption of bakery products, sweetened soft drinks and yogurt were usually very small. We conclude that the impact of the consumption of bakery products, sweetened soft drinks and yogurt on the quality of the diet of Spanish children is only modest, although it may contribute to aggravating certain unhealthy characteristics of their diet, particularly excess energy, saturated fats and sugars. Therefore, consumption of bakery products and sweetened soft drinks should be moderated, and priority given to consumption of low-fat, low-sugar yogurt.

Beverages↗
PubMed2005

Appetite sensations as a marker of overall intake.

The aim of this study was to evaluate the clinical utility of appetite sensations to characterize individual overall energy intake. A group of men (n 28) and women (n 23) was recruited to record their 'desire to eat', 'hunger', 'fullness' and 'prospective food consumption' (PFC) on visual analogue scales before a standardized meal test, immediately after and every 10 min for a period of 1 h after the meal. The 1 h post-meal area under the curve (1 h AUC) and the satiety quotient (SQ) were calculated for all appetite sensations. In a second visit, all participants were invited to eat three meals in order to measure total energy intake (TEI) and food preferences. Metabolic rate (MR) was also assessed to derive daily relative energy intake (REI) by subtracting this variable from TEI (TEI-MR=REI). The Three-Factor Eating Questionnaire scores were also calculated for all participants. One h AUC for fullness was the appetite sensation most strongly associated with TEI and REI (r-0.42, P< or =0.003 and r-0.32, P< or =0.05, respectively). SQ for fullness was the only predictor of TEI and REI (r-0.42, P< or =0.0003 and r-0.30, P< or =0.05, respectively). Restraint, disinhibition and hunger scores were not associated with appetite sensation variables. These results suggest that the fullness dimension seems to be a useful appetite sensation to predict long-term TEI and REI. Thus, assessment of appetite sensation such as fullness in response to a fixed load may be useful to evaluate individual overall energy intake.

Adult↗
PubMed2000

Quantitative prediction of overall seat discomfort.

Static seat characteristics (seat stiffness) and dynamic seat characteristics (vibration magnitude) can both influence judgements of seat comfort. It is proposed that seat comfort can be predicted on the basis of Steven's psychophysical law: psi = kphi(n), where psi is a sensation magnitude, phi is the stimulus magnitude and k is a constant. The law is modified to: psi = a + bphis[n(s)] + cphiv[n(v)], where phis and phiv represent seat stiffness and vibration magnitude, n(s) and n(v) are exponents determined by the rate of increase in discomfort associated with the stiffness and vibration magnitude, and a, b and c are constants. The stiffness of foam loaded to 490 N may indicate static seat comfort, while the vibration dose value (VDV) on the seat surface may indicate vibration discomfort. Two experiments with 20 subjects investigated this approach. The first experiment with five magnitudes of vibration, three foams and a rigid wooden flat seat yielded 0.929 for the exponent, n(v), for VDV. In the second experiment subjects judged the overall seat discomfort while exposed six vibration magnitudes with the same four seating conditions. This experiment yielded 1.18 for the exponent, n(s), for seat stiffness. The overall prediction of seat discomfort was given by: psi = -50.3 + 2.68phis1.18 + 101phiv0.929. The prediction equation provided more accurate estimates of subject discomfort than models using either the VDV alone or the stiffness alone, especially when the vibration magnitude was low or the seats were similar. An interaction variable between the VDV and the stiffness slightly improved the prediction. The equivalence of the two stimuli was given by log10 (stiffness) = 0.787 log10 (VDV) + 1.34, or log10 (VDV) = 1.27 log10 (stiffness) - 1.70.

Adult↗
PubMed1990

The usefulness of human figure drawings as an index of overall adjustment.

This study investigates the relation between global ratings of human figure drawings and psychological adjustment. The sample was comprised of a group of Vietnamese refugees who were evaluated at their entry into a residential education program. Adjustment was defined as the number of foster-care placements experienced by these clients during the 5 years following the program. Results showed that ratings of overall artistic quality, figure bizarreness, and estimated client adjustment all varied linearly as a function of number of foster-care placements. A fourth predictor variable, number of Koppitz emotional indicators, did not produce this result. All four predictor variables were found to be related, and it was shown that ratings of figure bizarreness alone adequately predicted the criterion. Implications of these results are discussed, and results suggest that projective drawings could provide a useful index of overall adjustment when better sources of information are not available.

Acculturation↗
PubMedDate not supplied

An improved olive oil overall migration test for plastics using Karl Fischer titration.

Karl Fischer titration has been used to eliminate the need to humidity-condition food contact plastics under test for overall migration into olive oil. The water content of the oil is measured before and after the migration test. This direct measure of the loss (or uptake) of water by the test plastic is then used in calculations of the overall migration. The use of Karl Fischer titration gives faster analysis with reduced labour input. The time savings varied from a few days to several weeks depending on the type of plastic. Karl Fischer titration is particularly useful in the high temperature testing of polar plastics where incomplete humidity conditioning can lead to erroneous results. The technique should be equally valuable when employing sunflower oil or the triglyceride HB307 in place of olive oil.

Dietary Fats, Unsaturated↗
PubMed2004

Influence of overall treatment time and radiobiological parameters on biologically effective doses in cervical cancer patients treated with radiation therapy alone.

The aim of the study was to examine the influence of overall treatment time (OTT) on the value of calculated biological effective doses (BEDs) for different biological variables. These variables were: tumour proliferation rate, different cell radiosensitivity (alpha=0.2, 0.3, and 0.4 /Gy), and different start time for repopulation (Tk=21, 28, and 35 days). Also the influence of age (</= 50 years >), Hb level (</= 116 g/l>), tumor proliferation rate (bromodeoxyuridine labelling index; BrdUrdLI), and DNA ploidy on survival after shorter (</= 60 days) or longer (>60 days) OTT was investigated. The study included 229 patients with cervix carcinoma treated entirely by standard radiotherapy (RT) (external beam RT plus low-medium dose-rate (LDR/MDR) brachytherapy (BT) at the Center of Oncology in Krakow. The linear quadratic equation was used to calculate BED, which is proportional to log cell kill. BEDs 10 (for tumours) were calculated with consideration of OTT for each patient and tumour proliferation rate (standardized potential doubling time; standardized Tpot) based on BrdUrdLI assessed on biopsy material before RT. Median OTT was 90 days (range 30-210). The mean calculated total BED for point A for tumour and 'early reactions' was equal to 103.0 Gy10. The longest median survival time--52 months--was seen for patients treated with OTT </= 60 days. If OTT exceeded 90 days to more than 120 days, loss in BED10 for relatively radiosensitive tumours (alpha=0.3-0.4/Gy and Tk=28 days) was equal to 0.37-0.26 Gy/day. However, for radioresistant tumours (alpha=0.2/Gy) it was 0.6 Gy/day. For fast proliferating tumours (BrdUrdLI >8.8%) BED loss was 1.4 Gy/day and for slowly proliferating tumours (BrdUrdLI </= 8.8%) it was 0.2 Gy/day. Assuming shorter (21 days) or longer (35 days) periods for Tk and relatively radiosensitive tumours similar BED loss of 0.38 Gy/day was observed. Kaplan-Meier analysis revealed that OTT </= 60 days was a significant prognostic factor for overall survival (OS) (p=0.019), disease-free survival (DFS) (p=0.0173), and local control (LC) (p=0.011). BED10 had significant influence on survival (p=0.047). Cox multivariate analysis revealed that for OTT shorter than 60 days the only favourable significant parameters were: age >50 years (p=0.003) and high Hb level (>116 g/l) (p=0.041). For longer treatments (OTT >60 days) the unfavourable parameters were: age </= 50 years (p=0.037), BrdUrdLI </= 8.8% (p=0.003), tumour aneuploidy (p=0.043), and BED10 </= 103 Gy (p=0.017). The examined tumour biological parameters should be taken into account for RT and provide a basis for adjuvant RT.

Adult↗
PubMed2005

The role of epidermal growth factor receptor and E-cadherin for the outcome of reduction in the overall treatment time of radiotherapy of supraglottic larynx squamous cell carcinoma.

Reduction of the overall treatment time (OTT) of radiotherapy results in increased T-site control in squamous cell carcinomas of the head and neck (HNSCC). However, the response is heterogeneous and accelerated repopulation of clonogenic tumour cells during therapy may be one of the factors determining this response. The aim of the present study was to identify the influence of the epidermal growth factor receptor (EGFr) and E-cadherin for T-site control when the OTT was reduced and whether the markers add information to the histopathological grading in selecting patients for accelerated radiotherapy. A total of 209 patients from randomized DAHANCA-trials with supraglottic larynx squamous cell carcinomas treated with primary radiotherapy with different OTT of 9(1/2), 6(1/2), and 5(1/2) weeks. Available formalin-fixed paraffin embedded tumour tissues were re-evaluated for histopathological characteristics and stained for EGFr and E-cadherin. Data were correlated with patient and tumour characteristics and 5-year T-site control. EGFr and E-cadherin were not associated with patient or tumour characteristics except that EGFr correlated to carcinomas with a well to moderate histopathological feature. Tumours with high EGFr or low E-cadherin did benefit from reduced OTT, and the combination of the two (high EGFr and low E-cadherin) had the most significant acceleration of treatment effect, compared with tumours with other combinations of EGFr and E-cadherin expression. Tumours with high expression of EGFr and low expression of E-cadherin showed the most significant increase in T-site control when the overall treatment time of radiotherapy was reduced, and the markers may be useful for selecting patients who will benefit from accelerated radiotherapy.

Adult↗
PubMedDate not supplied

Overall vigilance and sustained attention decrements in healthy aging.

Age differences in sustained attention were investigated using a high-event rate digit-discrimination task at 6 levels of stimulus degradation (lasting 8.1 min each). Twenty-one young, 21 middle-aged, and 20 old healthy subjects were studied. Overall sensitivity (d') was equivalent in all groups. Although all subjects showed a sensitivity decrement over blocks, there were no age-related differences in sustained attention capacity. All subjects had larger decrements in d' over blocks at higher degradation levels. However, the performance decrement at higher degradation levels was equivalent in all groups, indicating similar decrement rates in sensitivity with increasing demands on effortful processing. These results indicate that overall levels of vigilance and the ability to sustain attention over time are equivalent in all groups under conditions requiring both automatic (low-degradation) and effortful (high-degradation) stimulus processing.

Adult↗
PubMedDate not supplied

Overall and event-free survivals for acute lymphoblastic leukemia in children at a single institution in Taiwan.

The results of treatment for childhood acute lymphoblastic leukemia (ALL) have improved dramatically over the past three decades. The authors present the long-term outcome of patients (n = 151) with ALL enrolled in 4 consecutive clinical trials conducted from 1982 to 1993 at Mackay Memorial Hospital. During this period, the backbone of the treatment remained relatively unchanged, including a 3- to 4-drug remission induction, central nervous system (CNS)-directed therapy, and cyclic pulses of vincristine and dexamethasone during maintenance therapy. More intensive therapy, consisting of reintensification and addition of more drugs during maintenance, was reserved for high-risk and very-high-risk patients. The overall survival and event-free survival (+/- 1 SE) were 70 +/- 4.1% and 64 +/- 4.3 %, respectively, with follow-up ranging from 7.6 to 18.7years (median 12.2 year). The isolated CNS relapse rate was 4.3%. The dropout rate significantaly decreased from 35% in 1982-1984 to 0% in 1991-1993. Although the patient population is small, the overall results for childhood ALL at the authors' hospital are encouraging as compared to earlier reports in Taiwan.

Adolescent↗
PubMed2004

In vitro drug sensitivity and apoptosis induction in newly diagnosed pediatric acute lymphoblastic leukemia: correlation with overall survival.

The present study looked for any associations between in vitro drug sensitivity and clinical outcome in pediatric acute lymphoblastic leukemia (ALL) with the standard drugs used for leukemia therapy. A total of 72 samples were analyzed. In vitro sensitivity to drugs was tested by a methylthiazol-tetrazolium assay in 6 serial fold dilutions. Apoptosis was determined by TUNEL assay and apoptotic index was calculated for each sample. Patients sensitive to prednisone, asparginase, vincristine, and 6-mercapto purine had higher overall survival compared to patients whose tumor cells were resistant to these drugs (p < .01). For the other drugs tested, overall survival did not vary from that of the resistant patients. For doxorubicin, asparginase, vincristine, prednisone combination sensitivity, there was a significant worsening of prognosis from the extremely sensitive patients through an intermediate sensitive group to a most resistant group. The present study thus shows that in vitro drug-sensitivity testing provides significant prognostic information in childhood ALL.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Alcohol consumption and overall accident mortality in 14 European countries.

AIMS: To evaluate the effects of changes in aggregate alcohol consumption on overall accident mortality in 14 western European countries after 1950, and to compare traditional beer, wine, and spirits countries with respect to the impact of alcohol. DESIGN, SETTING AND PARTICIPANTS: The countries were sorted into three groups--traditional spirits countries of northern Europe, traditional beer countries of central Europe and wine countries of southern Europe. Gender- and age-specific annual mortality rates were analysed in relation to per capita alcohol consumption, utilizing the Box-Jenkins technique for time series analysis. All series were different to remove long-term trends. The results of the analyses in individual countries were pooled within each group of countries to increase the statistical power. MEASUREMENTS: Overall accident mortality data for 5-year age groups were converted to gender and age specific mortality rates in the age groups 15-29, 30-49 and 50-69 years. Rates were age adjusted within groups. Data on per capita alcohol consumption were converted to consumption per inhabitant 15 years and older. FINDINGS: The analyses demonstrated a statistically significant and positive relationship between changes in aggregate alcohol consumption in all three groups of countries. The estimated effect parameter was larger in northern Europe than in central Europe, and smallest in southern Europe. CONCLUSION: The results are compatible with the hypothesis that accident mortality rates are influenced by per capita alcohol consumption in southern, central and northern Europe. However, alcohol appears to play a larger role in northern Europe than in southern Europe.

Accidents↗
PubMed2002

Alternation of epirubicin and mitoxantrone in CHOP-like regimens retains efficacy and reduces overall toxicity in elderly patients with high and intermediate grade non-Hodgkin lymphomas.

Mitoxantrone and Epirubicin are active agents in non-Hodgkin's lymphomas (NHL). These drugs have reduced cardiotoxicity and therefore are indicated in treatment of elderly patients. Cyclophosphamide, mitoxantrone, vincristine and methylprednisone (CNOP) and cyclophosphamide, epirubicin, vincristine and methylprednisone (CEOP) are combination chemotherapy and contain Mitoxantrone and Epirubicin that have been shown to be effective in treatment of NHL of intermediate and highgrade of malignancy in the elderly. Since Mitoxantrone and Epirubicin are partially non-cross resistant their combined use may diminish emergence of resistant neoplastic clones and may be associated with enhanced anti-neoplastic activity. In this study, a polychemotherapy schedule alternating 3 cycles of CEOP and 3 cycles of CNOP, was used in a single center between December 1988 and April 1995 to treat 41 previously untreated patients, over 60 years of age affected by intermediate or high grade non-Hodgkin's lymphoma according to the Working Formulation. In treated patients, 57.5% achieved complete response, 35% partial response and 7.5% were non-responders. Overall survival was 52.4 % at 4 years, Disease free survival (DFS) for complete responders was 48.9%. Only one case of severe extrahematological toxicity (grade 3-4 WHO) was observed. Severe mucositis (grade 3-4 WHO) was absent, and delayed administration of chemotherapy was required in only 7/230 cycles. No treatment related deaths were registered. This regimen achieved results comparable to that of other anthracycline or mitoxantrone based chemotherapy, but determined lower toxicity. Alternating CEOP and CNOP may improve overall toxicity.

Aged↗
PubMed2006

The addition of oral idarubicin to a chlorambucil/dexamethasone combination has a significant impact on time to treatment failure but none on overall survival in patients with low grade non-Hodgkin's lymphoma: Results of the Scotland and Newcastle Lymphoma Group randomized NHL VIII trial.

Two hundred untreated patients with low grade NHL (KIEL), including 155 follicular NHL, were randomized to six courses of treatment with chlorambucil 20 mg m-2 for 3 days and dexamethasone 4 mg bd for 5 days (CD) vs the same regimen plus oral idarubicin 10 mg m-2 for 3 days (CID). Responding patients could be randomized to no further treatment or maintenance treatment for up to 36 months with alpha interferon. Complete remissions/CRu were more frequent in the CID arm (35% vs 24%) but the overall response rate was similar; 87/91 (96%) vs 86/92 (93%). Overall survival (OS) did not differ between the two arms. Time to treatment failure (TTTF) was prolonged in the CID arm, p = 0.03; median time 28 vs 19 months. TTTF for the B-cell follicular group alone was for CID (77 patients) 33 months vs 18 months for CD (78 patients). Interferon conferred no apparent benefit. The Follicular Lymphoma International Prognostic Index (FLIPI) is confirmed as a good predictor of risk groups including a group of 23% with shorter survival. The addition of the oral anthracycline, idarubicin, led to a significant improvement in TTTF with low toxicity. The use of radiotherapy in this sub-group may have contributed to this result. CID is a potential for combination with antibody therapy particularly in older patient groups.

Administration, Oral↗
PubMed2006

Omnibus permutation tests of the overall null hypothesis in datasets with many covariates.

Tests of the overall null hypothesis in datasets with one outcome variable and many covariates can be based on various methods to combine the p-values for univariate tests of association of each covariate with the outcome. The overall p-value is computed by permuting the outcome variable. We discuss the situations in which this approach is useful and provide several examples. We use simulations to investigate seven omnibus test statistics and find that the Anderson-Darling and Fisher's statistics are superior to the others.

Computer Simulation↗
PubMed2001

Racial differences in rates of type 2 diabetes in American women: how much is due to differences in overall adiposity?

BACKGROUND: Although the rates of type 2 diabetes attributable to obesity have been documented by numerous studies, little attention has been paid to an important question of, "what fraction of the differences in rates of diabetes between high-risk and low-risk women is due to their differences in prevalence of obesity? This study aimed, therefore, to determine how much of the relative difference in the rates of type 2 diabetes between high-risk non-Hispanic Black and low-risk non-Hispanic White American women can be attributed to differences in overall adiposity. METHODS: Data (n = 1,222) from the Third National Health and Nutrition Examination Survey (1988-94) was used in this investigation. Obesity was defined as body mass index of 30 kg/m2 or more. Estimates of population attributable risks and relative attributable risks were derived using multiple logistic regression models, adjusting for age, smoking and alcohol intake. RESULTS: There were within and between population differences in the impact of obesity on diabetes. The impact of obesity on diabetes as measured by odds ratio and population attributable risk was greater for White women compared to Black women. Obesity was independently associated with a 4-fold (OR = 4.43; 95% CI: 2.65, 7.44) and almost a 2-fold (OR = 1.85; 95% CI: 0.99, 3.47) increased risks of diabetes for White and Black women, respectively. Being Black was associated with an almost 2-fold (OR = 1.86; 95% CI: 1.22, 2.82) increased risk of diabetes relative to White. The population attributable risks of diabetes due to obesity were 49.9% and 28% in Whites and Blacks, respectively. Over one-third (39%) of the difference in rates of diabetes between Black and White women was attributable to differences in the prevalence of overall obesity, adjusting for age, smoking and alcohol consumption. CONCLUSIONS: The result of this study indicating that obesity is a significant factor in explaining the higher prevalence of diabetes among Black women has public health relevance. Since obesity is a preventable and an avoidable risk factor for type 2 diabetes in all populations, the result of this investigation presents a compelling reason to emphasize public health measures to educate women on the need to reduce weight, particularly the high-risk black American women.

Adipose Tissue↗
PubMed2001

Experimental determination of the overall perturbation factor for the NACP chamber in electron beams for dmax < d < or = d80.

In electron beam dosimetry with an ionization chamber, a factor that corrects for the cavity perturbation of the medium, Prepl, and one to account for the disturbance due to the chamber wall material differing from the medium, Pwall, are required. The overall perturbation correction factor, p(q) = PreplPwall, has been introduced because of the difficulty in separately measuring these two components. An advantage of parallel-plate ionization chambers is that p(q) has been shown to be close to unity at dmax. However, many dosimetry applications require knowledge of the overall perturbation factor at depths greater than dmax. We determined p(q) for the NACP chamber at depths beyond dmax by intercomparing percentage depth dose measurements made with it with those obtained with a PTW/diamond detector for which p(q) was taken as unity at all the measurement depths. Data were obtained at depths corresponding to approximately the 90 and 80 per cent of the dose maxima for 20, 16, 12 and 6 MeV incident electrons. The beam energy at depth, Ed, and the percentage depth-dose gradient varied from 1.4 to 14.3 MeV and 0 to 5.8% mm(-1) respectively. Our results show that within the estimated uncertainty of 1.3%, p(q),NACP is unity over the range of energies and dose gradients studied.

Biophysical Phenomena↗