Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Freedom”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 325 records · Page 18Linked to original sources
PubMed2004

Postoperative adjuvant and salvage radiotherapy for prostate cancer: impact on freedom from biochemical relapse and survival.

OBJECTIVES: To determine the therapeutic outcomes in patients with high-risk prostate cancer treated with adjuvant or salvage radiotherapy (RT) after radical prostatectomy. METHODS: Between 1982 and 2000, 163 patients were treated with RT after radical prostatectomy. Adjuvant therapy was administered to 107 consecutive node-negative patients (T2-T4N0) referred to our institution less than 1 year after surgery for postoperative RT. Salvage treatment was delivered to 56 patients for a persistently elevated prostate-specific antigen level, biochemical relapse after surgery, or local recurrence. RESULTS: The median follow-up was 70 months (range 2 to 167) from the initiation of RT. Patients treated with adjuvant RT were less likely than those treated with salvage RT to experience biochemical relapse. At 5 and 10 years, the rate of freedom from biochemical relapse was 80% and 66% in the adjuvant cohort compared with 39% and 22% for patients treated with salvage intent, respectively (P <0.0001). This did not translate into a statistically significant improvement in absolute survival (72% versus 70%) or cause-specific survival (93% versus 86%) at 10 years. On multivariate analysis, neoadjuvant hormonal therapy (P = 0.0187), presence of seminal vesicle involvement (P = 0.0002), and referral indication for postoperative RT (salvage versus adjuvant RT; P <0.001) were predictors of biochemical relapse. CONCLUSIONS: In this single-institution experience, patients at high risk of disease recurrence after radical prostatectomy realized a greater biochemical relapse-free survival benefit when treated with adjuvant RT than with salvage RT. Neoadjuvant hormonal therapy and seminal vesicle involvement predicted for inferior treatment outcome.

Aged↗
PubMed2006

Percentage of positive biopsies associated with freedom from biochemical recurrence after low-dose-rate prostate brachytherapy alone for clinically localized prostate cancer.

OBJECTIVES: To examine the relationship between the percentage of positive biopsies (PPBs) and freedom from biochemical recurrence (FFBR) in men treated with low-dose-rate prostate brachytherapy (LDRPB) alone. The PPBs has been associated with FFBR in men treated with radical prostatectomy and external beam radiotherapy for prostate cancer. METHODS: This report concerns 108 men treated with LDRPB alone between November 1997 and December 1999. All patients had clinically localized prostate cancer confirmed by biopsy. All men were treated with iodine-125 to 144 Gy. FFBR was estimated using the product-limit method. Putative covariates for FFBR, including T stage, Gleason score, pretreatment prostate-specific antigen level, minimal dose received by 90% of the target volume, and PPBs, were examined using the proportional hazards regression model. RESULTS: The median follow-up was 61 months. Of the 108 men, 13 developed evidence of biochemical relapse at a median of 25 months. The 5-year estimate of FFBR was 87% (95% confidence interval 81% to 93%) for the entire cohort. On univariate analysis, prostate-specific antigen, T stage, minimal dose received by 90% of the target volume, and PPBs were associated with FFBR. In the multivariate model, the PPBs was the only variable that predicted for FFBR (P = 0.002). The 5-year estimate of FFBR was 95% for patients with less than 50% PPB disease versus 63% in patients with more than 50% PPB disease (P < 0.0001). CONCLUSIONS: The PPBs is an important independent predictor of FFBR after LDRPB alone. The FFBR after LDRPB in the group of patients with more than 50% PPBs was poor.

Aged↗
PubMed2006

Application of non-structural protein antibody tests in substantiating freedom from foot-and-mouth disease virus infection after emergency vaccination of cattle.

There has been much debate about the use of the so-called "vaccinate-to-live" policy for the control of foot-and-mouth disease (FMD) in Europe, according to which, spread of the FMD virus (FMDV) from future outbreaks could be controlled by a short period of "emergency" vaccination of surrounding herds, reducing the need for large-scale preemptive culling of at-risk animals. Since vaccinated animals may become subclinically infected with FMDV following challenge exposure, it is necessary to either remove all vaccinates (vaccinate-to-kill) or to detect and remove vaccinates in which virus is circulating or has established persistent infections (vaccinate-to-live), in order to rapidly regain the most favoured trading status of FMD-free without vaccination. The latter approach can be supported by testing vaccinated animals for the presence of antibodies to certain non-structural proteins (NSP) of FMDV, which are induced by infection with the virus, but not by vaccination with purified FMD vaccines. Using test sensitivity and specificity data established at a recent workshop on NSP assays [Brocchi E, Bergmann I, Dekker A, Paton DJ, Sammin DJ, Greiner M, et al. Comparative performance of six ELISAs for antibodies to the non-structural proteins of foot-and-mouth disease. Vaccine, in press], this paper examines the ways in which serological testing with NSP ELISAs can be used and interpreted and the effect that this will have on the confidence with which freedom from infection can be demonstrated within guidelines specified by the World Animal Health Organisation and the European Commission.

Animals↗
PubMed1989

Kinematics of helical motion of microorganisms capable of motion with four degrees of freedom.

The kinematics of helical motion are described for an organism with four degrees of freedom, relative to the organism's frame of reference. It can rotate about any of three orthogonal axes, but can translate only in the direction of one axis. In particular, equations are developed for calculating the pitch, radius, and angular frequency of the helical path from the translational and rotational velocities of the microorganism, correcting, and expanding the analysis of Gray J. (1955. J. Exp. Biol. 32:775-801).

Cell Movement↗
PubMed2002

A new two-degree-of-freedom level control scheme.

In this paper, a two-degree-of-freedom level control scheme for delay free processes is analyzed. The nominal performance and robustness are examined. And sufficient and necessary conditions for robust stability are derived. An alternative level control scheme is developed for processes with dead time and suboptimal controllers that can produce smooth response are derived analytically based on the internal model control. The scheme has an important feature in that it is simple and transparent in design and in the corporation of performance and robust stability issues. Numerical examples are provided to compare the proposed scheme with those developed.

Equipment Design↗
PubMed2001

Assessment of the accuracy of a human arm model with seven degrees of freedom.

We are proposing a human arm model that consists of three rigid segments with seven degrees of freedom. The shoulder joint was modeled as a ball-and-socket joint and the elbow and wrist joints were modelled as skew-oblique joints. Optimal parameters for this model were calculated on the base of in vivo recordings with a spatial tracking system. The criterion of optimality was defined as the minimum of the mean-square deviation between the experimentally obtained sensor positions and orientations and their positions and orientations calculated by solving the direct kinematics problem. The minimal value of the direct kinematics error was found to be 0.5-0.6cm for sensor positions and 5-7 degrees for sensor orientations. We are proposing that these values serve as the assessment for the accuracy of the arm model.

Adult↗
PubMed2003

A single-degree-of-freedom dynamic model predicts the range of human responses to impulsive forces produced by power hand tools.

The human operator is modelled as a single-degree-of-freedom dynamic mechanical system for predicting the response to impulsive torque reaction forces produced by rotating spindle power hand tools such as nutrunners or screwdrivers. The model uses mass, spring and damping elements to represent the standing operator supporting the tool in the hand. It was hypothesized that these mechanical elements are affected by work location and vary among individuals. These elements were ascertained by measuring the resulting frequency and amplitude of a freely oscillating defined mechanical system when externally loaded using maximal effort to oppose its motion. Twenty-five subjects (13 female, 12 male) participated in the full factorial experiment that measured the effects of gender, vertical and horizontal work location for various tool shapes (in-line, pistol, right angle), and orientations (horizontal and vertical). The mean operator stiffness decreased from 1721 to 1195 N/m when the horizontal work location increased from 30 to 90 cm in front of the ankles for a pistol-grip handle used on a vertical surface. Males had greater mass moment of inertia of (0.0099 kg m2) than females (0.0072 kg m2) for an in-line handle used on a horizontal surface. Internal validation by independently measuring apparatus torque found that the model satisfactorily explained the measured operator dynamics with an average error of 2.86%. Group variance reflects the range of operator capacities to react against power hand tool generated forces for the sample group and therefore it may also be useful for understanding the range of capacities among a group of operators performing similar tasks.

Adult↗
PubMed2001

Pretreatment nomogram for predicting freedom from recurrence after permanent prostate brachytherapy in prostate cancer.

OBJECTIVES: To develop a prognostic nomogram to predict the freedom from recurrence for patients treated with permanent prostate brachytherapy for localized prostate cancer. METHODS: We performed a retrospective analysis of 920 patients treated with permanent prostate brachytherapy between 1992 and 2000. The clinical parameters included clinical stage, biopsy Gleason sum, pretreatment prostate-specific antigen (PSA) value, and administration of external beam radiation. Patients who received neoadjuvant androgen deprivation therapy were excluded. Failure was defined as any post-treatment administration of androgen deprivation, clinical relapse, or biochemical failure, defined as three PSA rises. Patients with fewer than three PSA rises were censored at the time of the first PSA rise. Data from two outside institutions served as validation. RESULTS: A nomogram that predicts the probability of remaining free from biochemical recurrence for 5 years after brachytherapy without adjuvant hormonal therapy was developed using Cox proportional hazards regression analysis. External validation revealed a concordance index of 0.61 to 0.64, and calibration of the nomogram suggested confidence limits of +5% to -30%. CONCLUSIONS: The pretreatment nomogram we developed may be useful to physicians and patients in estimating the probability of successful treatment 5 years after brachytherapy for clinically localized prostate cancer.

Adenocarcinoma↗
PubMed1998

Task-dependent reduction of the number of degrees of freedom in sensorimotor systems.

In this paper we present a concise review of experiments on sensorimotor performance in man from the perspective of new opportunities provided by research in microgravity, which will contribute to our basic understanding of sensorimotor processes. In particular, we will discuss some new results on strategies for dealing with the large number of degrees of freedom in biological limbs with special emphasis on human motor control and on the specific role for mono- and bi-articular muscles. Finally, we propose some ideas for future experiments on motor function in microgravity, which will reveal new basic knowledge about the role of the CNS in motor control and which will contribute to a better performance of man in sensorimotor tasks in microgravity conditions.

Extremities↗
PubMed2002

A method of indirect registration of the coordinates of condylar points with a six-degree-of-freedom jaw tracker.

Previous studies have indicated that the location of a condylar point can significantly influence its trajectory. The aim of this investigation was to develop a method of registering the location of radiographically defined condylar points in the coordinate system of a six-degree-of-freedom jaw-tracking device and to determine the accuracy of this method by using a perspex model in one experiment and a dry skull in another. A direct measurement ('the gold standard') of condylar point coordinates in the coordinate system of JAWS3D was done using a three-dimensional (3D) digitizer (MicroScribe-3DX). The indirect measurement used a distributed fiducial marker as the interface between the coordinate system of MicroScribe-3DX (which was used to register the fiducial marker and the JAWS3D coordinate system) and the coordinate system of the CT scans (used to define condyle anatomy and the relation with the fiducial marker). The coordinates of condylar points could then be calculated in the coordinate system of JAWS3D. The results showed that the indirect method could register condylar point coordinates on either side to an accuracy of approximately 0.5 mm.

Computer Simulation↗
PubMed2002

Analysis of sampling strategies to substantiate freedom from disease in large areas.

In this paper, we deal with the strategies of surveys to substantiate freedom from disease for a certain territory. Infection might not be distributed homogeneously. So, a relatively high within-herd prevalence might be observed while the herd-level prevalence is lower. For this situation, we compare various two-stage sample strategies. The calculation of appropriate sample sizes becomes quite complicated. The theoretical generalization of the hypergeometric distribution by Cameron and Baldock [Prev. Vet. Med. 24 (1998) 1] introduces a simple way to evaluate multi-stage sample sizes while regarding real-test properties. We demonstrate the theoretical foundations of these calculations. These principles open up the possibility of optimizing costs or other relevant variables, by choosing the appropriate sample strategy (each of which ensures the same alpha-level for the first stage). In addition, we evaluate the statistical power of the complete strategies under consideration.Furthermore, we apply our theoretical results to a data example of Brucella melitensis. We used the herd-size situation in Germany, characterized by many small sheep holdings and only a few large ones. The consequences of real-test properties on sample sizes and on the applicability of several strategies are discussed.

Animals↗
PubMed1998

A new probability formula for surveys to substantiate freedom from disease.

Surveys to substantiate freedom from disease are becoming increasingly important. This is due to the changes in rules governing international trade in animals and animal products, and to an increase in disease eradication and herd-level accreditation schemes. To provide the necessary assurances, these surveys must have a sound theoretical basis. Until now, most surveys have been based on the assumption that the screening test used was perfect (sensitivity and specificity both equal to one), and/or that the study population was infinite. Clearly, these assumptions are virtually always invalid. This paper presents a new formula that calculates the exact probability of detecting diseased animals, and considers both imperfect tests and finite population size. This formula is computationally inconvenient, and an approximation that is simpler to calculate is also presented. The use of these formulae for sample-size calculation and analysis of survey results is discussed. A computer program, 'FreeCalc', implementing the formulae is presented along with examples of sample size calculation for two different scenarios. These formulae and computer program enable the accurate calculation of survey sample-size requirements, and the precise analysis of survey results. As a result, survey costs can be minimised, and survey results will reliably provide the required level of proof.

Animal Diseases↗
PubMed2003

Learning to coordinate redundant degrees of freedom in a dynamic balance task.

The present study investigated Bernstein's [The co-ordination and regulation of movements, 1967] proposal regarding the three stages of learning in the changing coordination and control of redundant joint-space degrees of freedom. Six participants practiced maintaining balance on a moving platform that was sinusoidally translated in the anterior-posterior direction for 30 trials on day 1 and 10 trials on day 2. At the beginning of practice, the motion of the torso and limb segments was less coherent in the attempt to compensate for the movement of the support surface in retaining a balanced posture. However, with practice, the organization of a compensatory postural coordination mode became highly coherent and also progressively utilized the passive, inertial forces generated by the movement of the support surface. The findings support the propositions that: (a) the pathway of change over time in the coordination pattern of the torso and joint motions depends on the task goal and constraints to action and (b) the changes in limb and torso motion are in support of the learning of a global body center of mass/platform dynamic.

Adult↗
PubMed1998

3D shoulder position measurements using a six-degree-of-freedom electromagnetic tracking device.

OBJECTIVE: To describe a recording and processing methodology for obtaining kinematic data of the shoulder which meets three more criteria besides usual requirements regarding precision and accuracy: sufficient speed, obtaining complete 3D kinematics including joint rotations, and usage of coordinate systems based on reference points. DESIGN: Static recordings of shoulder bone orientations during standardized humerus elevations based on the palpation technique using a six-degree-of-freedom electromagnetic tracking device. BACKGROUND: An easy, fast, well standardized measurement methodology for obtaining complete 3D shoulder kinematic data is urgently needed for fundamental musculoskeletal and clinical research. METHODS: A measurement methodology was designed and developed. Shoulder kinematics were obtained from repeated measurements on 15 healthy subjects performed by two observers. Inter-trial, inter-day, inter-observer and inter-subject variability were established. Results were compared to literature. RESULTS: Complete kinematic descriptions were obtained. A measurement speed of about one position per second could be reached. The measured kinematics and accuracy of the measurements were found to be in concordance with the literature. CONCLUSION: All previously formulated criteria for a clinical useful method for obtaining shoulder kinematics have been met.

Journal Article↗
PubMed1995

Exobiology research on Space Station Freedom.

The Gas-Grain Simulation Facility (GGSF) is a multidisciplinary experiment laboratory being developed by NASA at Ames Research Center for delivery to Space Station Freedom in 1998. This facility will employ the low-gravity environment of the Space Station to enable aerosol experiments of much longer duration than is possible in any ground-based laboratory. Studies of fractal aggregates that are impossible to sustain on Earth will also be enabled. Three research areas within exobiology that will benefit from the GGSF are described here. An analysis of the needs of this research and of other suggested experiments has produced a list of science requirements which the facility design must accommodate. A GGSF design concept developed in the first stage of flight hardware development to meet these requirements is also described.

Cosmic Dust↗
PubMed1998

Improved freedom from PSA failure with whole pelvic irradiation for high-risk prostate cancer.

PURPOSE: To determine the impact of whole pelvic irradiation on the risk of PSA failure in prostate cancer patients, at high predicted risk for lymph node involvement, receiving definitive radiotherapy. MATERIALS AND METHODS: Between October 1987 and December 1995, 506 patients with clinically localized prostate cancer were treated with definitive radiotherapy at UCSF and affiliated institutions. Treatment consisted of 4-field whole pelvic irradiation followed by a prostate-only boost, or prostate-only treatment (median follow-up was 35 months and 30 months, respectively). PSA failure was defined as: 1. a PSA value > or = 1 ng/ml; or 2. a PSA value that rose > or = 0.5 ng/ml in < or = 1 year posttreatment on two consecutive measurements, with the first rise defined as the time of failure. The calculated risk of lymph node positivity (%rLN+) was defined as 2/3(iPSA) + 10(GS-6), and high risk was defined as %rLN+ > or = 15%. Univariate and multivariate analyses were performed. RESULTS: A total of 201 high-risk patients were identified. High-risk patients who received whole pelvic irradiation had significantly improved freedom from PSA failure compared to those who received prostate-only treatment (median PFS = 34.3 months vs. 21.0 months; p = 0.0001). Potential confounding variables, including initial PSA, Gleason score, T stage, radiation dose, year of treatment, use of three-dimensional (3D) conformal techniques, and use of hormone therapy, did not account for the observed difference in time to PSA failure. Multivariate analysis revealed type of radiation treatment to be the most significant independent predictor of outcome. CONCLUSION: Whole pelvic radiotherapy significantly improves the PSA failure-free survival in patients with a high calculated risk of lymph node positivity.

Analysis of Variance↗
PubMed2003

Physiological axial compressive preloads increase motion segment stiffness, linearity and hysteresis in all six degrees of freedom for small displacements about the neutral posture.

The stiffness of motion segments, together with muscle actions, stabilizes the spinal column. The objective of this study was to compare the experimentally measured load-displacement behavior of porcine lumbar motion segments in vitro with physiological axial compressive preloads of 0, 200 and 400 N equilibrated in a physiological fluid environment, for small displacements about the neutral posture. These preloads are hypothesized to increase stiffness, hysteresis and linearity of the load-displacement behavior. At each preload, displacements in each of six degrees of freedom (+/-0.3 mm AP and lateral translations, +/-0.2 mm axial translation, +/-1 degrees lateral bending and +/-0.8 degrees flexion/extension and torsional rotations) were imposed. The resulting forces and moments were recorded. Tests were repeated after removal of posterior elements. Using least squares, the forces at the vertebral body center were related to the displacements by a symmetric 6 x 6 stiffness matrix. Six diagonal and two off-diagonal load-displacement relationships were examined for differences in stiffness, linearity and hysteresis in each testing condition. Mean values of the diagonal terms of the stiffness matrix for intact porcine motion segments increased significantly by an average factor of 2.2 and 2.9 with 200 and 400 N axial compression respectively (p<0.001). Increases for isolated disc specimens averaged 4.6 and 6.9 times with 200 and 400 N preload (p<0.001). Changes in hysteresis correlated with the changes in stiffness. The load-displacement relationships were progressively more linear with increasing preload (R(2)=0.82, 0.97 and 0.98 at 0, 200 and 400 N axial compression respectively). Motion segment and disc load-displacement behaviors were stiffer, more linear and had greater hysteresis with axial compressive preloads.

Animals↗
PubMed2002

A user perspective on type 1 diabetes: sense of illness, search for freedom and the role of the pharmacy.

The aim of the study described in this article was to explore young type 1 diabetic patients self-perceived knowledge, perception of diabetes, ways of regulating insulin intake, purpose of behaviour and attitudes about and requirements of the pharmacy. The interest group for utilising this study comprises pharmacy practice researchers and staff at community pharmacies who plan to focus on type 1 diabetic patients. The study, based on 10 semi-structured qualitative interviews, showed how young type 1 diabetic patients can be divided into three different groups based on the way they regulate their insulin intake. These groups are described and discussed in detail in the article. What drives the diabetic patients in terms of regulating insulin intake is primarily their experience-based knowledge and their search for freedom.

Adult↗