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At least 91 records · Page 5Linked to original sources
PubMed2003

Orthopaedic crossfire--Stem modularity is unnecessary in revision total hip arthroplasty: in the affirmative.

Numerous options are available for femoral stem fixation in revision total hip arthroplasty, including cemented stems, proximally-coated cementless stems, extensively coated cementless stems, impaction grafting cemented stems, and modular cementless stems. In terms of versatility, ease of insertion, use with an extended trochanteric osteotomy, and clinical results, extensively coated cementless stems remain the gold standard. Modular cementless stems have not matched the clinical results of extensively coated cementless stems. In addition, modular stems introduce increased complexity, cost, and potential complications and are therefore, rarely, if ever, necessary in revision total hip arthroplasty.

Arthroplasty, Replacement, Hip↗
PubMed1978

Altruism: its characteristics and evolution.

Altruism is a group phenomenon in which some genes or individuals, which must be presumed to be selfish, benefit others at cost to themselves. The presumption of selfishness and the fact of altruism are reconciled by kin-group selection and by reciprocal altruism. Kin-group selection is clearly visible only in special cases; its role even among social insects may be overestimated; it is probably usually inhibited by competition. However, reciprocal altruism is ubiquitous. All altruism is: (i) potentially reciprocal; (ii) potentially profitable to altruists as well as to recipients; (iii) environmentally determined, usually by position of individuals in group or environmental situations; and (iv) a net-gain lottery. These generalizations are illustrated by four idealized cases; the difficulty of applying them to real cases is illustrated by alarm-calling in groups of birds. Although altruism is a group phenomenon, it evolves by individual selection, by processes equivalent to co-evolutions. Its evolution is: (i) opposed by competition; (ii) costly, complex, and slow, and tending to produce an imprecise flexible altruism rather than a precisely detailed one; and (iii) supplemented by group selection (differential extinction of groups). That altruism in human beings conforms to these generalizations is a good working hypothesis. However, analysis does not "take the altruism out of (human) altruism." Humans do not calculate it, but behave altruistically because they have human altruistic emotions.

Altruism↗
PubMed1979

Practical approach to hypertension. 1. Diagnostic evaluation.

The comprehensive diagnostic evaluation once recommended for hypertension is no longer practical or necessary. In the majority of cases, a thorough history, physical examination, and basic laboratory workup are sufficient to determine the severity of the hypertension and to detect target organ damage. Secondary hypertension is truly rare in clinical practice and should not be pursued with complex, costly, and possibly risky tests unless specific indications are present.

Adult↗
PubMed2006

An evaluation of four measures of adolescents' exposure to cigarette marketing in stores.

This study evaluates four measures of exposure to retail cigarette marketing in relation to adolescent smoking behavior. The measures are (a) shopping frequency in types of stores known to carry more cigarette advertising than other store types, (b) shopping frequency in specific stores that sell cigarettes in the study community, (c) the amount of exposure to cigarette brand impressions in stores where students shopped, and (d) perceived exposure to cigarette advertising. The study combined data from classroom surveys administered to 6th-, 7th-, and 8th-grade students in three California middle schools, and direct store observations quantifying cigarette marketing materials and product placement in stores where students shopped. Logistic regression models were used to examine how each exposure measure related to the odds of ever smoking and susceptibility to smoke, controlling for grade, gender, ethnicity, school performance, unsupervised time, and exposure to household and friend smoking. Frequent exposure to retail cigarette marketing as defined by each of the four measures was independently associated with a significant increase in the odds of ever smoking. All but the measure of exposure to store types was associated with a significant increase in the odds of susceptibility to smoke. Four measures of exposure to retail cigarette marketing may serve equally well to predict adolescent smoking but may vary in cost, complexity, and meaning. Depending on the outcomes of interest, the most useful measure may be a combination of self-reported exposure to types of stores that contain cigarette marketing and perceived exposure to such messages.

Adolescent↗
PubMedDate not supplied

Traditional sampling with laboratory analysis and solid phase microextraction sampling with field gas chromatography/mass spectrometry by military industrial hygienists.

The opinions or assertions contained herein are the private ones of the authors and are not to be construed as official or reflecting the views of the United States Department of Defense or the Uniformed Services University of the Health Sciences. Rapid on-site detection and identification of environmental contaminants to which personnel may be exposed is often needed during military deployment situations. The availability of military industrial hygienists with capabilities for "complete" on-site exposure assessment of chemical species should allow detection and identification of a number of important stressors almost immediately following sample collection. Portable gas chromatography/mass spectrometry (GC/MS) provides a rapid and efficient separation of volatile and semivolatile organic analytes, accompanied by sensitive electron impact ionization-mass spectrometry (EI-MS) detection. The use of GC/MS in the field is limited, however, by equipment cost, complexity of the equipment, and the analytical process. Additionally, a skilled operator is needed to obtain useful separations and to interpret mass spectral data. To demonstrate benefits and limitations of "complete" exposure assessment capabilities, a previously unidentified complex mixture, produced by thermal dispersion of riot control agents, was examined. Established active sampling methods were used with laboratory analyses. Solid phase microextraction, a passive sampling method that simplifies preparation for GC/MS analysis, also was used with a field-portable GC/MS system. Both sampling/analysis methods were used to detect CS riot control agent-derived air contaminants dispersed from riot control type canisters through oxidizer-supported combustion of a chemical fuel.

Chemistry Techniques, Analytical↗
PubMed2004

Current approaches to the management of osteoporosis in men.

PURPOSE: The epidemiology, pathophysiology, diagnosis, and management of osteoporosis in men are reviewed. SUMMARY: Men with osteoporosis account for approximately one fifth of all patients with osteoporosis, and their morbidity and mortality rates from this disease are higher than in other patients. Guidelines specifically addressing the management of osteoporosis in men are not available. Lifestyle modifications, including smoking cessation, limited alcohol consumption, routine exercise, and fall prevention strategies, are beneficial to maintain bone health. Appropriate calcium and vitamin D intakes are critical components of any osteoporosis management strategy. Drug therapy should be initiated in all men at high risk for fracture. Alendronate is indicated for the treatment of osteoporosis. It is considered first-line therapy because of its efficacy and safety profiles. Teriparatide is indicated for the management of osteoporosis in high-risk men, but the drug's cost, complex administration schedule, and potential risks have caused it to be restricted to a second-line therapy. Other options reserved for select patients include calcitonin and testosterone. Further studies are needed to better understand the distinctive features and management strategies for men with osteoporosis. CONCLUSION: While the rate of osteoporosis in men is lower than in women, the consequences are possibly more devastating. Evaluation of secondary causes, especially hypogonadism, is important, as they can play a significant role in the development of osteoporosis in men. All men should be educated to improve modifiable risk factors and maintain recommended daily intakes of calcium and vitamin D. Bone mineral density should be evaluated in high-risk men using central dual energy x-ray absorptiometry, and drug treatment should be considered in those with a history of low-trauma fracture or significant bone loss.

Humans↗
PubMed1994

Growing a classification tree using the apparent misclassification rate.

A method to determine the size of a classification tree is proposed. This method is based on the change of the apparent misclassification rate (AMR) of the tree at each growing stage. The method is simple and fast compared to the other classification tree methods, which are based on minimizing a cost complexity function. To test the method, it was used to classify species of fungi, and the results are in good agreement with those obtained by linear discriminant analysis. Also, 21 proteins with known structures and functions were classified using the proposed method. For this purpose the coefficient of variation for several properties of the secondary structures of these proteins has been used. Again, the results were in good agreement with the classification obtained previously using dynamic programming.

Algorithms↗
PubMed2003

Progress in imaging stroke: emerging clinical applications.

Recent years have seen major advances in the imaging of cerebrovascular disease. Although quantitative positron emission tomography (PET) has continued to be the gold standard in acquiring functional imaging data, with recent developments continuing to bear fruit, it remains a complex, costly, and not readily available technique. The emphasis in this overview is in the development of the newer magnetic resonance (MR) techniques, such as diffusion-weighted (DWI) and perfusion-weighted imaging (PWI), which allow rapid assessment of the underlying pathophysiology in acute ischaemic stroke. This is of major importance in classifying patients according to pathophysiology rather than clinical and structural imaging data, which may be essential in deciding therapy such as thrombolysis (which has proven benefit within 3-6 h of clinical onset, but can also lead to harmful haemorrhagic transformation) and/or neuroprotection, as well as patient selection in clinical trials. In conjunction with magnetic resonance angiography (MRA), DWI-PWI has been shown to improve the diagnosis and clinical management of stroke. Other novel MR techniques which have yet to reach the clinician, such as spectroscopic imaging, diffusion tensor imaging (DTI) and blood oxygenation level-dependent functional MRI (BOLD-fMRI), are currently established research tools which provide data about infarct evolution, fibre disruption and the mechanisms of stroke recovery. Electrophysiological methods including transcranial magnetic stimulation (TMS) and magneto-encephalography (MEG) will not be addressed here.

Brain Ischemia↗
PubMed1999

RN participation in organizational decision making and improvements in resident outcomes.

In the study on which this article is based, nursing homes with the most improvements in resident outcomes had greater registered nurse (RN) participation in decision making than did homes with the least improvements. The results suggest that nursing homes that want to improve quality can use RN participation to make improvements without significantly increasing costs. Complexity theory served as a framework for the study.

Decision Making, Organizational↗
PubMedDate not supplied

Development and initiation of computer generated documentation for burn patient care.

Burn care is costly, complex, and poorly reimbursed. Capturing evaluation and management codes is an essential step in obtaining reimbursement for services rendered. For surgeons used to billing on the basis of Current Procedural Terminology codes, this represents a significant paradigm shift. In an effort to document the care provided and increase compliance with billing standards, we created computerized history and physical examination notes and progress notes specifically for burn patients. Drop down menus are included to answer directed queries, which allows the majority of the documentation to be completed with a point and click of the mouse. The note is completed by the house staff except for the "assessment and plan," which are entered by the attending physician who reviews and then electronically signs the note. A log of electronically signed notes is generated weekly for billing purposes. The use of these computerized documents has been reviewed and approved by the coding and quality assurance specialists within our billing organization. We believe these tools maximize the efficiency of documenting burn patient care, while minimizing the effort necessary to comply with evaluation and management guidelines. The aim of this study was to test the new computerized method at our institution to see whether it would improve documentation for evaluation and management services provided to burn patients. The results prove that this new system accomplished the goal we had set.

Burn Units↗
PubMed2004

The World Cancer Report and the burden of oral cancer.

The WHO has recently provided the most comprehensive global examination of cancer to date, through the publication of the World Cancer Report (WCR). According to IARC-WHO estimates, cancer rates are set to increase at an alarming rate, from 10 million new cases globally in 2000, to 15 million in 2020. However, the report states that we have the opportunity to stem the predicted sharp increase in new cancer cases by taking action now, especially through planning effective cancer control strategies, such as reducing tobacco consumption, suggesting healthy lifestyle and diet, and performing early detection through screening. Although cancer of the oral cavity is largely related to lifestyle and can be easily detected and diagnosed at early stages through a 5 min visual inspection of the oral mucosa, actual figures concerning its prevention and early detection are dismal. Most oral cancers are detected at a late stage, requiring complex, costly and often ineffective therapies. Similarly, current research, educational and financial resources are focused on procedures burdened by high cost, high morbidity and unacceptable high mortality. Here we suggest that it is time to change this common point of view towards this disease and to alter this trend, stressing that there is no other oncologic specialty in which the WCR preventive guidelines could be applied in such an easy and effective manner, as in the field of oral cancer.

Cost-Benefit Analysis↗
PubMed2000

A proposal for the integration of immunohistochemical staining and DNA-based techniques for the determination of TP53 mutations in human carcinomas.

The p53 protein plays an important role in the control of the cell cycle and DNA repair. Mutations in the TP53 gene may be a prognostic factor for certain forms of human cancer, with specific mutation sites being associated with significantly worse prognosis, particularly for colorectal and breast cancer. Thus, standardization of accurate, rapid, and cost-effective techniques for the detection of TP53 mutations is a high priority. At present, the only widely available technology that reliably detects and defines all mutations is DNA sequencing. However, the routine sequencing of the entire TP53 gene in all breast and colorectal cancer cases in hospital laboratories is prohibitively costly, complex, and time consuming. In order for the analytical power of DNA to be accessed by the routine laboratory, initial screening using immunohistochemistry, which is widely used as a test for detection of accumulated, mutated protein, followed by heteroduplex analysis of exons 4 to 9 to detect frameshift mutations in immunohistochemistry-negative cases, is proposed. To illustrate the effectiveness of this approach, 28 cases of head and neck squamous-cell carcinomas that were known to contain TP53 mutations were retrospectively analyzed. All missense mutations stained positive on immunohistochemistry using the monoclonal antibody DO7, and all insertions and deletions, even those involving a single nucleotide, were positive using an extremely simple heteroduplex analysis. Only rare nonsense mutations were not detected by this strategy. Nevertheless, application of these results to published data suggests that the prescreening would detect 80% of mutations but would result in a 75% reduction in the sequencing load of the laboratory.

Antibodies, Monoclonal↗
PubMed1997

Anaesthesia for the management of distal radius fractures in adults in Scottish hospitals.

The objective of this study was to determine the methods of anaesthesia used for the reduction of distal radius fractures in adults in Scotland and to compare this with the UK situation. The method used was a telephone questionnaire of accident and emergency doctors in 25 Scottish hospitals dealing with trauma. Thirty-two per cent still use general anaesthesia routinely for these procedures despite its cost, complexity and need for admission in the majority of cases. Forty-four per cent now use the Bier's block technique of regional anaesthesia, with the attendant advantages of ease of use, rapid recovery and no need for admission in the majority of patients. Twelve per cent use intravenous sedation and 12% use haematoma blocks for manipulations. It is concluded that Bier's block may be the anaesthetic method of choice for the management of distal radius fractures both in efficiency and economic terms in Scotland. However, training for Bier's blocks needs to be standardized and improved.

Adult↗
PubMed2004

Neurophysiologic evaluation of spastic hypertonia: implications for management of the patient with the intrathecal baclofen pump.

A number of techniques attempt to objectively quantify various clinical characteristics associated with spastic hypertonia and related motor disorders. These range in cost, complexity, physiologic basis of measured response, and invasiveness. With a greater range of treatment options for spasticity and an increase in the number of centers participating in studies of interventions for spasticity, published reports reflect increasing use of objective quantification techniques. We review studies that highlight the potential utility of neurophysiologic techniques, including the H-reflex, F-wave, and flexion withdrawal reflex, in the objective evaluation of response to intrathecal baclofen administration. The accumulated knowledge suggests that neurophysiologic evaluation is useful for assessing spinal cord responsiveness, and we recommend it as an adjunct to clinical evaluation when judging the overall effectiveness of intrathecal baclofen administration.

Baclofen↗
PubMed2004

Methods for haptic feedback in teleoperated robot-assisted surgery.

Teleoperated minimally invasive surgical robots can significantly enhance a surgeon's accuracy, dexterity and visualization. However, current commercially available systems do not include significant haptic (force and tactile) feedback to the operator. This paper describes experiments to characterize this problem, as well as several methods to provide haptic feedback in order to improve surgeon's performance. There exist a variety of sensing and control methods that enable haptic feedback, although a number of practical considerations, e.g. cost, complexity and biocompatibility, present significant challenges. The ability of teleoperated robot-assisted surgical systems to measure and display haptic information leads to a number of additional exciting clinical and scientific opportunities, such as active operator assistance through "virtual fixtures" and the automatic acquisition of tissue properties.

Journal Article↗
PubMed1993

Cost/benefit criterion for selection of pulsed Doppler ultrasound spectral mean frequency and bandwidth estimators.

A flexible selection criterion for spectral estimators based on the weighted statistical accuracy (benefit) of estimation of decisive spectral parameters under the constraint of low computational complexity (cost) is proposed. This new cost/benefit criterion also selects the model order for parametric spectral estimators-selecting model orders significantly lower than those determined by accepted criteria. The importance of different Doppler signal parameters (e.g., mean frequency and spectral bandwidth) and their accuracy of estimation is incorporated by the use of weighting factors. The use of this method with simulated Doppler signals led to the selection of the modified covariance Alt estimator.

Arteriosclerosis↗
PubMed2005

Investigation into sleep disturbance of patients suffering from cluster headache.

The new discoveries relating to cluster headache (CH) encouraged the study of the relationship of the hypothalamus to respiratory physiology and its comorbidity with sleep apnoea. The question is whether the apnoeas are more frequent during REM sleep and the desaturations could be involved as triggers of the cluster attacks. Furthermore, could the connection with the hypothalamus, already proved, be responsible for an alteration in the structure of REM sleep and a chemoreceptor dysfunction. We set out to analyse when polysomnography investigation is necessary in patients with CH. We studied 37 patients suffering from episodic CH, 31 (83.8%) men and six (16.2%) women. For the control group, we selected 35 individuals, 31 (88.6%) men and four (11.4%) women. There was a greater percentage of obstructive sleep apnoea (OSA) in patients with CH (58.3%) compared with the control group (14.3%) and with the general population (2-4%). In cases of pain during sleep, the majority is deflagrated during the REM phase, following a desaturation episode. A stratified analysis of the apnoea/hypnoea index relating to body mass index (BMI) and age showed that patients with CH have 8.4 times more chance of exhibiting OSA than normal individuals (P < 0001). This risk increases to 24.38 in patients with a BMI > 25 kg/m(2) and increases to 13.5 in patients > 40 years old. Surprisingly, the risk decreases sharply in patients with a BMI < 25 kg/m(2) and who are < 40 years old. Due to the fact that polysomnography is a complex, costly and sometimes difficult examination, we suggest, in concordance with the results, that it should be carried out routinely in patients with CH that exhibit a BMI of > 25 kg/m(2) and/or in patients who are > 40 years of age.

Adolescent↗
PubMed1996

Dual sensor VVIR mode pacing: is it worth it?

Dual sensor ventricular demand rate responsive (VVIR mode) pacing was compared with single sensor rate responsive pacing to assess whether this new development should be more widely incorporated in modern pacemaker devices. A within patient randomized, double-blind crossover study involving ten patients, mean age 67.4 years (70% male), had Medtronic Legend Plus dual sensor VVIR pacemakers implanted for high grade AV block and chronic or persistent paroxysmal atrial fibrillation. Performance values were compared to 20 healthy control subjects of a similar age and gender. Patients were both subjectively and objectively assessed after 2 weeks of out-of-hospital activity in VVIR mode (minute ventilation sensing), VVIR mode (activity sensing), VVIR mode (dual sensor), and VVI mode (no rate response). All patients were assessed for subjective preference for, and objective improvement in, any pacing modality as assessed by standardized daily activity protocols and graded exercise treadmill testing. Subjective perception of exercise capacity and functional status was significantly lower in VVI mode (P < 0.05) compared to any of the VVIR modes, which did not differ. After completion of the study 70% of patients chose VVIR as their preferred mode, with 30% expressing no preference. Forty percent preferred activity sensor VVIR mode pacing, 30% preferred dual sensor VVIR mode pacing, and 70% found either dual sensor VVIR mode, minute ventilation sensor VVIR mode, or both modalities least acceptable. No patient found activity sensing VVIR mode least acceptable. Graded treadmill testing revealed significantly lower exercise tolerance during VVI mode pacing (P < 0.01) compared to the VVIR modalities, which did not differ. Overall, chronotropic response was best with dual sensor pacing during standardized daily activity protocols and during the standard car journey. The data from this study suggest that there is no marked clinical advantage obtained from the use of dual sensor devices over current activity sensing ventricular demand rate responsive pacemakers, but with the probable added disadvantages of increased size, complexity, cost, and decreased longevity.

Activities of Daily Living↗