Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “corrective measures”

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 235 records · Page 13Linked to original sources
PubMed2002

Combining DNA sequences and morphology in systematics: testing the validity of the dragonfly species Cordulegaster bilineata.

Morphological and molecular techniques are rarely combined when answering questions of taxonomic validity. In this study, we combine morphological techniques with DNA sequences to determine the validity of the dragonfly species Cordulegaster bilineata. The two dragonfly species C. bilineata and C. diastatops are very similar in size, body color, and morphological characters, and due to these similarities, the status of C. bilineata as a valid species is in question. In this study we compare morphological measurements of males and internal transcribed spacer 1 (ITS-1) sequences of rDNA between the two taxa. The hamule measurements (where copulation occurs) of males show little difference between the taxa in question, but the anal appendage measurements (where the male first contacts the female) show marked divergence between the two taxa. Cluster analysis with these anal appendage measurements correctly assigns almost all individuals measured into their respective taxon. PCR amplification products of ITS-1 display a approximately 50 bp size difference between C. bilineata (n = 4) and C. diastatops (n = 5) regardless of collection site. Sequence data for these amplifications show 51 bp missing in one locus in the ITS-1 of C. bilineatarelative to C. diastatops. A lone population of C. diastatops from Wisconsin has three individuals with ITS-1 products that match the size of both C. bilineata and C. diastatops. One individual from this population appears to yield two ITS-1 amplification products that match both C. bilineata and C. diastatops. Although this population may be evidence for hybridization between the two taxa, such hybridization is not necessarily sufficient to disqualify the validity of a separate species designation for C. bilineata. Morphology and ITS-1 sequences depict a high degree of divergence that is consistent with species-level differences.

Animals↗
PubMed1976

Special pacemaker catheter techniques. The transmediastinal placement of sensing electrodes.

The clinical utilization of atrial programmed pacemakers is limited by the lead systems available for sensing of atrial activity. The endocardial method of lead placement is burdened by a dislodgement rate of up to 30 per cent. Alternatively, the patient must submit to the risks of a thoracotomy. Thirty-one patients have been treated with a transmediastinally, retrocardially positioned atrial detector electrode. In 20 patients (65 per cent) the detector performed as desired with no postimplant revision. In 11 patients (35 per cent) corrective measures were required primarily to correct lead placement; seven of these were corrected under local anesthesia merely by pulling the catheter. Spontaneous lead dislocation occurred in four patients. Four patients (13 per cent) underwent remediastinoscopy due to cranial displacement of the detector electrode with a resulting decrease in atrial potential to less than 0.5 mV. For technical reasons, the lead placements were performed without the benefit of x-ray illumination, with only an ECG check of the posterior atrial wall, and this may account for the relatively high incidence of revision. Transmediastinal placement of sensing electrodes presents a practicable alternative to methods presently used.

Adult↗
PubMed2004

Improving the prediction of final infarct size in acute stroke with bolus delay-corrected perfusion MRI measures.

PURPOSE: To investigate whether bolus delay-corrected dynamic susceptibility contrast (DSC) perfusion MRI measures allowed a more accurate estimation of eventual infarct volume in 14 acute stroke patients using a predictive tissue classifier algorithm. MATERIALS AND METHODS: Tissue classification was performed using a expectation maximization and k-means clustering algorithm utilizing diffusion and T2 measures (diffusion-weighted imaging [DWI], apparent diffusion coefficient [ADC], and T2) combined with uncorrected perfusion measures cerebral blood flow ((CBF) and mean transit time [MTT]), bolus delay-corrected perfusion measures (cCBF and cMTT), and bolus delay-corrected perfusion indices (cCBF and cMTT with bolus delay). RESULTS: The mean similarity index (SI), a kappa-based correlation statistic reflecting the pixel-by-pixel classification agreement between predicted and 30-day T2 lesion volumes, were 0.55 +/- 0.19, 0.61 +/- 0.15 (P < 0.02) and 0.60 +/- 0.17 (P <0.03), respectively. Spearman's correlation coefficients, comparing predicted and final lesion volumes were 0.56 (P < 0.05), 0.70 (P < 0.01), and 0.84 (P < 0.001), respectively. We found a more significant correlation between predicted infarct volumes derived from bolus delay-corrected perfusion measures than from conventional perfusion measures when combined with diffusion measures and compared with final lesion volumes measured on 30-day T2 MRI scans. CONCLUSION: Bolus delay-corrected perfusion measures enable an improved prediction of infarct evolution and evaluation of the hemodynamic status of neuronal tissue in acute stroke.

Acute Disease↗
PubMed1997

Atmospheric leakage and method for measurement of gas exchange rates of a crop stand at reduced pressure.

The variable pressure growth chamber (VPGC) was used in a 34-day functional test to grow a wheat crop using reduced pressure (70 kPa) episodes totalling 131 hours. Primary goals of the test were to verify facility and subsystem performance at 70 kPa and to determine responses of a wheat stand to reduced pressure and modified partial pressures of carbon dioxide and oxygen. Operation and maintenance of the chamber at 70 kpa involved continuous evacuation of the chamber atmosphere, leading to CO2 influx and efflux. A model for calculating CO2-exchange rates (net photosynthesis and dark respiration) was developed and tested and involved measurements of chamber leakage to determine appropriate corrections. Measurement of chamber leakage was based on the rate of pressure change over a small pressure increment (70.3 to 72.3 kPa) with the pump disabled. Leakage values were used to correct decreases and increases in chamber CO2 concentration resulting from net photosynthesis (Ps) and dark respiration (DR), respectively. Composite leakage corrections (influx and efflux) at day 7 of the test were 9% and 19% of the changes measured for Ps and DR, respectively. On day 33, composite corrections were only 3% for Ps and 4% for DR. During the test, the chamber became progressively tighter; the leak rate at 70.3 kPa decreasing from 2.36 chamber volumes/day pretest, to 1.71 volumes/day at the beginning of the test, and 1.16 volumes/day at the end of the test. Verification of the short-term leakage tests (rate of pressure rise) were made by testing CO2 leakage with the vacuum pump enabled and disabled. Results demonstrate the suitability of the VPGC or conducting gas exhange measurements of a crop stand at reduced pressure.

Air Conditioning↗
PubMed1999

Response time and word recognition using a Modified-Rhyme monitoring task: list equivalency and time-order effects.

OBJECTIVE: The purpose of this study was to assess list equivalency and time-order effects of word recognition scores and response time measures obtained using a digital recording of the Modified Rhyme Test (MRT) with a response time monitoring task (Mackersie, Neuman, & Levitt, 1999). DESIGN: Response times and percent correct measures were obtained from listeners with normal hearing using the MRT materials presented at a signal to noise ratio of +3 dB. Listeners were tested using a word-monitoring task in which six alternatives were presented in series and listeners pushed a button when they heard the target word (as displayed on the computer monitor). Listeners were tested in two sessions. During each session each of the six MRT lists was administered once. Time-order effects were examined both between and within test sessions. RESULTS: All lists were equivalent for both speech recognition accuracy and response time except List 1, which showed slightly higher percent correct scores than the other lists. Varied patterns of systematic change over time were observed in 75% of the listeners for the response time measures and for 33% of the listeners for the percent correct measures. CONCLUSIONS: Lists 2 through 6 of this version of the MRT are equivalent, with List 1 producing slightly higher word recognition scores. Systematic changes over time in response time data for the majority of listeners suggest the need for careful implementation of the test to avoid time-order effects.

Adult↗
PubMed1994

Optical and mathematical corrections of micropipette measurements of red blood cell geometry during anisotonic perifusion.

Accurate knowledge of red blood cell (RBC) membrane surface area and cellular volume is critical to understanding the geometric factors that affect RBC deformability. A useful method to determine RBC geometry is via micropipette aspiration in which the cell partially enters the tip of a glass pipette with a diameter of about 2 microns. Measurement of the cell while in the pipette allows calculation of cell geometry, but such measurements are subject to several artifacts. Herein, we analyze the effects of three artifacts on calculated RBC geometry during experimental osmotic manipulation. 1) The pipette internal diameter, as measured optically, requires correction for refractive index and focusing errors; 2) the pipette barrel is tapered rather than cylindrical; 3) the observed RBC outline is affected by a diffraction phenomenon. These optical and mathematical errors were all found to influence the calculated RBC geometry; both absolute values and relative changes during osmotic manipulation were affected. For RBC in isotonic medium, use of the above corrections significantly (p < 0.001) reduced the calculated area by 3.7%, the volume by 7.0%, and the minimum cylindrical diameter by 3.9%. The calculated membrane area dilation for cells exposed to hypotonic media was also significantly reduced; at 200 mOsm, the dilation was 2.8% +/- 0.2% without correction vs. 1.5% +/- 0.2% when all corrections were employed (p < 0.01). We therefore suggest that micropipette aspiration of RBC requires use of these correction techniques to obtain accurate values for RBC geometry and that such correction methods are of particular importance when RBC of different sizes are compared.

Adult↗
PubMed2007

Intraoperative awakening of the patient during orthognathic surgery: a method to prevent the condylar sag.

PURPOSE: The intraoperative diagnosis, during orthognathic procedures, of an unfavorable condylar position is highly desirable. A simple technique that can reliably identify a malpositioned condyle intraoperatively has obvious advantages. The manual positioning of the condyle is easier, but it requires the utmost care and an experienced operator. Muscle tone is described as maintaining contact across the temporomandibular joint. The anesthetized and curarized patient has a condylar position posterior to that in the same patient when he is awake, with the same seating force applied. Under general anesthesia, the condyle may be inferior and might not feel stable until it moves posteriorly and has adequate compression of the retrodiscal tissues on the posterior wall. Relapse of the occlusion as a result of changes in the condylar position may occur immediately after the removal of the temporary intermaxillary fixation (IMF). The surgeon needs to understand the mechanism of condylar sag and the specific patterns of malocclusion that it may produce. This will enable him to make a diagnosis and to implement the appropriate corrective measures, providing the opportunity for immediate correction of condylar position, thereby obviating the need for a second operation or orthodontic compromise. MATERIALS AND METHODS: A study group (group A, 76 patients) and a control group (group B, 73 patients) were randomly formed from the dysgnathic patients scheduled for bimaxillary orthognathic surgery (Le Fort I osteotomy and bilateral sagittal split osteotomy). The free mandibular proximal segment was gently and manually positioned in the glenoid fossa. All the mandibles were fixed with bicortical screws. In group A, immediately after the fixation, IMFs were removed and the occlusions were checked with light digital pressure on the chin, then the patients were rapidly awakened (maintaining the intubation) in a state of conscious analgo-sedation and asked to open and close, and to laterally move the mandible. If clinical examination of the passive and active movements of the mandible was suitable, the anesthesia was reinforced and the operation was concluded. RESULTS: In 11 of the 76 patients of group A, malocclusion was noted, after the rigid fixation, with the method of digital pressure on the chin; the intraoperative awakening of the patients confirmed the clinical appearance and it provided further clinical signs to identify the offending condyle and to favor appropriate corrections. In 8 of the group A patients, malocclusions were not noted with manipulation of the mandible, but they were pointed out during the intraoperative awakening, and then they were appropriately corrected. In 2 of the group B patients, malocclusion was noted, after the rigid fixation, with the method of digital pressure on the chin, and it was immediately corrected. In 7 of the group B patients, malocclusion was not noted during the operation with the method of digital pressure on the chin, but it was noted at the end of the surgical procedure (12-24 hours after). CONCLUSION: Muscle tone, muscular activity, and proprioception appear to have important roles in the clinical evidence of a postoperative malocclusion during the intraoperative awakening; they can reliably implement the accuracy of the diagnosis of condylar sag, and they can favor its correction.

Adolescent↗
PubMed1975

Exstrophy of the bladder. I. Long-term results in a series of 37 cases treated by ureterosigmoidostomy.

Of the 37 patients with exstrophy of the bladder in whom ureterosigmoidostomy was selected as the mainstay of treatment 4 died of causes related to the procedure. Faulty judgment and poor followup accounted for these deaths, which might well be preventable today. In 18 survivors, or approximately half of the entire series, the operation has held up well for many years, with no further surgical procedure being required for complications. In 12 patients, or approximately a third of the group, remedial operations for complications attributable to the ureterosigmoidostomy have been required but it was elected to retain this form of diversion. The long-term end result in these patients also remains acceptable. Combining these 2 groups 30 of 37 patients with ureterosigmoidostomy may be considered to have been eventually successful. However, in 7 of 37 patients the method was a frank failure, in that 4 patients died and 3 required substitution of another form of diversion. While all forms of treatment of exstrophy of the bladder leave much to be desired, results obtainable in today's setting lead us to recommend ureterosigmoidostomy as first choice in the management of this disorder. This recommendation is accompanied by the admonition that systematic followup is imperative so that if things do go badly from the clinical, laboratory or urographic viewpoint corrective measures can be done before renal deterioration occurs. The measures required may range from simple correction of electrolytes to conversion to an ileal loop.

Adolescent↗
PubMed1976

Ultracentifuge studies of the binding of IgG of different subclasses to the Clq subunit of the first component of complement.

Normal IgG and myeloma proteins of the IgG1, 2, 3,and 4 subclasses were mixed with human Clq and studied in the analytical ultracentrifuge for complex formation. Binding of IgG to Clq is apparent both from the enlargement of area and from the increase in sedimentation rate of the well-separated schlieren peak of Clq. The accurate determination of binding parameters requires that sedimentation rates be corrected for hydrodynamic interaction, and area measurements corrected for the Johnston-Ogston effect. At the highest immunoglobulin concentrations employed in these studies more than ten IgG molecules are bound to each Clq. If we assume that the number of binding sites must be an integral multiple of 6, then the data best support a 12 binding site model, although an 18 site model cannot be rule out. Myeloma IgG proteins of all subclasses bind to Clq, with affinities decreasing in the order G3 greater than G1 greater than G2 greater than G4. No binding of IgA to Clq could be detected.

Binding Sites↗
PubMed1975

Prejudice and dietary counseling.

Current medical practice requires us to be able to educate and alter an individual's approach to health maintenance. The objective is to prevent illness--not only to treat illness. This approach should result in keeping people out of hospitals and clinics. Diet should be thought of as a noun, not a verb. It is not synonymous with the corrective measures it supposedly sill insure, i.e., correct obesity, reduce hypertension, control blood lipid abnormalities. In keeping with this approach, USAF medical team members should be able to do dietary counseling. This paper will examine each of these topics, emphasizing dietary prejudice at the level of the counselor, the subject and his family, and the USAF medical team.

Aerospace Medicine↗
PubMed2000

Prostate-specific antigen and prostate cancer.

Serum prostate-specific antigen (PSA) measurement is used to investigate patients with lower urinary tract symptoms and to screen for prostatic malignancy in symptom-free males over 50 years of age. Approximately 60% of patients with early (prostate-confined) occult malignancy show increased serum PSA levels, as do some 20% of patients with prostatic symptoms from benign prostatic disease. When PSA is only slightly raised, serial PSA measurements, correction for prostatic volume and especially measurement of free (unbound) PSA (which is reduced in prostatic malignancy) may assist the differentiation of prostatic cancer from benign hypertrophy. Serial measurements are also of value for monitoring treatment of prostate cancer and for post-treatment surveillance.

Aged↗
PubMed2004

[Hypertriglyceridemia--diagnostics, risk and treatment].

BACKGROUND: Hypertriglyceridemia and low HDL cholesterol values are associated with adiposity, type 2 diabetes and metabolic syndrome. METHODS: This review article is based on literature studies, data from Rikshospitalet and Furst Medical Laboratory, sales figures for fibrates and clinical experience. RESULTS AND INTERPRETATION: Insulin resistance is a common contributory cause to hypertriglyceridaemia. In hypertriglyceridaemia, fasting glucose, HbA1c, TSH, creatinine, ALAT, ASAT, gamma GT, ALP and urine strips should be measured. The patient must be evaluated with regard to adiposity, use of alcohol, eating disorders and pregnancy. Direct measurement of LDL cholesterol gives a correct measure independent of the triglyceride level up to 13.0 mmol/L. LDL cholesterol levels may be low despite high total cholesterol levels and high triglyceride levels. Diet and lifestyle intervention is important. Blood sugar control is crucial. Statins are the first choice of drugs in combined hyperlipidaemia. Isolated hypertriglyceridaemia >10 mmol/L represents a large risk for pancreatitis. Purified omega-3 fatty acids, fibrates and eventually niacin are the drugs of choice in this condition. If LDL cholesterol levels are elevated, statins should also be considered. Combination of statin/fibrate or statin/niacin increase the risk of myopathy.

Anticholesteremic Agents↗
PubMedDate not supplied

Contraceptive continuation among adolescents attending family planning clinics.

An attempt to find a reliable way to measure contraceptive continuation among teenagers was made in a study of 445 adolescents under age 18 who made an initial visit to one of nine federally funded family planning clinics in the Philadelphia area in 1980 and 1981. The participants were interviewed at their initial visit and at six and 15 months to collect information on background characteristics, pregnancy history and contraceptive use. A cross-check of the information on contraceptive use reported during the study showed that 38 percent of the respondents who reported that they had been continuous users during the 15 months supplied information at other points indicating that they had not always used contraceptives during that period. In an attempt to examine the effects of adolescent reporting errors on measures of contraceptive use, the investigators constructed three alternative measures of contraceptive continuation. The simplest measure assessed current use at 15 months. A second measure accepted only reports of continuous use at 15 months and ignored inconsistent data. The third measure corrected for inconsistent data. Applying these measures to the study population produced proportions of contraceptive continuation ranging from a low of 43 percent when the most stringent measure was used to a high of 82 percent for the current-use category. Whatever the measure used, much of the discontinuation appears to have occurred in the first three months after the initial visit to a family planning clinic.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2000

Evaluation of waist circumference, waist-to-hip ratio, and the conicity index as screening tools for high trunk fat mass, as measured by dual-energy X-ray absorptiometry, in children aged 3-19 y.

BACKGROUND: A central fat pattern has adverse health implications in both children and adults. Because adiposity tracks from childhood into adulthood, the ability of simple anthropometric techniques to correctly measure truncal adiposity in childhood needs to be assessed. OBJECTIVES: We sought to assess the validity of waist circumference, waist-to-hip ratio (WHR), and the conicity index as indicators of trunk fat mass in children and adolescents. DESIGN: Trunk fat mass (kg) was measured with dual-energy X-ray absorptiometry in 278 girls and 302 boys aged 3-19 y. Receiver operating characteristic (ROC) curves and areas under the curves (AUCs) for the ROCs were calculated to compare the relative abilities of the anthropometric measures to correctly identify children with high trunk fat mass (z score for our study population of > or =1). RESULTS: The 80th percentile for waist circumference correctly identified 89% of girls and 87% of boys with high trunk fat mass (sensitivity) and 94% of girls and 92% of boys with low trunk fat mass (specificity). Waist circumference performed significantly better as an index of trunk fat mass than did WHR or the conicity index, as shown by the AUCs in girls and boys, respectively: waist circumference AUCs = 0.97 and 0.97, conicity index AUCs = 0.80 and 0.81, and WHR AUCs = 0.73 and 0.71. Our cutoffs for high trunk fat mass and high waist circumference are provided for both sexes for each year of age. CONCLUSION: Waist circumference provides a simple yet effective measure of truncal adiposity in children and adolescents.

Abdomen↗
PubMedDate not supplied

In vivo measurements of lung corrections for fast-neutron therapy.

Silicon diodes were inserted into the esophagus and bronchus of anesthetized rhesus monkeys in order to measure the corrections to tumor dose resulting from intervening lung tissue during fast-neutron therapy. The derived corrections were applied to tumor doses for patients being treated for cancer of the esophagus on the fast-neutron beam at TAMVEC. In vivo dosimetry performed on these patients using silicon diodes in the esophagus confirmed the accuracy of the lung corrections. The measured dose and calculated dose agreed to within 4% for four different patients. Tha magnitude of the correction is on the order of 16% for the typical esophageal cancer patient. These studies were also done with Cobalt-60 in order to test, against other data, the results obtained with this animal model.

Animals↗
PubMed1994

[Osteophyte formation in the knee joint: a radiological study].

Reported here are the results of a study on the significance of osteophyte formation in the osteoarthritic knee joint. The osteophyte formation was examined in a total of 795 cases involving 1040 joints. Of these, 415 cases (660 joints) had no symptoms of osteoarthritis of the knee joint (Group A); while the other 380 (380 joints) had primary osteoarthritis of the knee joint (Group B). The osteophyte location and osteophyte length were determined in all cases of Group A and Group B. The rate of annual increase in osteophyte length was determined in 224 cases (369 joints) of Group A (average study period: 7.1 years) and in 122 cases (122 joints) of Group B (average study period: 7.5 years). A special measuring unit called the "spur index" was devised for the present study to determine a corrected measurement of the osteophyte length; 1 spur index unit corresponded to 1/100 of the width of the proximal tibial articular surface. By using this spur index, measurements could be corrected for the magnifying effect of X-ray photography and for variations in the size of knee joints. On the assumption that age, obesity, arteriolosclerosis and femorotibial angle were factors that promoted the progression of osteoarthritis in the knee joint, the correlation between the osteophyte length and each of these factors was investigated. A significant difference in osteophyte length, and in the annual increase in osteophyte length, was found between Group A and Group B, but no difference between them with regard to osteophyte location. A significant correlation was found between the osteophyte formation and each of the above-mentioned factors. The correlation was strongest with the femorotibial angle followed by age, arteriolosclerosis and obesity, in that order.

Adult↗
PubMed1996

[Food habits in the school population from rural areas].

OBJECTIVE: To find the nutritional habits, qualitatively speaking, of school-children in our area in order to analyse their possible nutritional deficiencies and establish corrective measures. DESIGN: A crossover study with a randomised sample, stratified by school years. SETTING: A school in a rural area. PATIENTS AND OTHER PARTICIPANTS: A sample of students from this school: 101 out of 247 (41%). MEASUREMENTS AND RESULTS: Using a closed survey without prior notice to the pupils, the food taken the day before at different meals was recorded and placed in each of the 7 groups of the nutritional circle. In addition two food groups considered of high energy content and low nutritional value were included (group 8, cakes and group 9, sweets). 17.82% of pupils had correct nutrition. 99% had milk for breakfast. 37.62% had only milk for breakfast. 46% did not consume vegetables all day. 34% did not consume fruit all day. 34% did not consume pulses all day. 72.28% consumed cakes and/or sweets at some time during the day. CONCLUSIONS: It can be concluded that these school-children eat low-quality food and that this is independent of school cycles or gender. The food of 82% of school-children is incorrect, with insufficient vegetables, fruit and/or pulses. They eat little for breakfast. We propose introducing, jointly with the teachers, measures to correct the problems found.

Child↗
PubMed1991

Assessment of lawn care worker exposure to dithiopyr.

Eighteen ChemLawn lawn care specialists were monitored for worker exposure by both passive dosimetry and biological monitoring techniques in the performance of normal duties of mixing/loading and application of Dimension herbicide to turfgrass. Passive dosimetry was performed, utilizing cotton gauze patches, silica gel air sampling absorption media, and hand washes as per US Environmental Protection Agency Pesticide Assessment Guidelines. Biological monitoring was performed by analysis of all urine specimens collected from each specialist from initiation until 72 h after application of dithiopyr. The mean body dose estimate from urinalysis of the specimens collected over the 72 h period was 4.60 x 10(-5) mg/kg/lb applied. The passive dosimetry body dose estimates using dermal deposition measurements corrected for skin penetration and simulated inhalation measurements were calculated for the two clothing scenarios observed in the worker tests. The mean body dose estimate for a fully clothed specialist wearing a long-sleeved shirt was 8.09 x 10(-5) mg/kg/lb while for a specialist wearing a short-sleeved shirt the estimate was 3.62 x 10(-4) mg/kg/lb. The lower leg regions, which were protected by long pants and boots, had the highest exposure by passive dosimetry data.

Animals↗