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At least 1,099 records · Page 61Linked to original sources
PubMed1994

Correlates of impaired function in older women.

OBJECTIVE: To determine the factors associated with impaired function in older women. DESIGN: Cross-sectional analysis of baseline data collected for a multicenter, prospective study of risk factors for osteoporotic fractures. SETTING: Four clinical centers in Portland, Oregon, Minneapolis, Minnesota, Baltimore, Maryland, and the Monongahela Valley, Pennsylvania. PARTICIPANTS: A total of 9,704 ambulatory, non-black women, aged 65 years and older, recruited from population-based listings. MEASUREMENTS: Independent variables, including demographic and historical information (medical conditions, health habits, and medications) and physiologic measures (anthropometry, blood pressure, mental status, vision, and neuromuscular performance) were obtained from a baseline questionnaire, interview, and examination. Measurement of function was assessed by self-reported ability to perform six physical and instrumental activities of daily living (ADL) and impaired function (dependent variable) was defined as difficulty performing three or more physical and instrumental ADLs. RESULTS: In order of decreasing strength of association, hip fracture, osteoarthritis, parkinsonism, slower walking speed, lower hip abduction force, back pain, greater Quetelet index, osteoporosis, former alcohol use, stroke, never drinking alcohol, lower mental status, use of anxiolytics and/or sleeping medications, inability to hold the tandem position, postural dizziness, cataracts, greater waist to hip ratio, lower physical activity in the past year, greater lifetime cigarette consumption, and lower grip strength were independently associated with impaired function in multivariate analyses. Age, low educational level, diabetes, current heavy alcohol use, postural hypotension, depth perception, and contrast sensitivity were not independent predictors. A combination of neuromuscular performance measures, including decreased muscle strength and impaired balance and gait, appeared to account for the effect of age on disability. CONCLUSION: A combination of many factors, including medical conditions, health habits such as obesity, smoking, alcohol abstinence, and physical inactivity, and direct measures of neuromuscular performance are associated with impaired function in older women.

Activities of Daily Living↗
PubMed1980

The use of the Nd-YAG and the CO2 laser in neurosurgery.

Over the last 3 years 130 patients have been operated on using laser techniques. This technique was chosen where technical difficulties were anticipated due to the size, the vascular supply or the localization of the process. Although the use of laser techniques requires experimental work, before it can be applied clinically some distinct advantages could be demonstrated when compared with the use of the bipolar cautery. Due to its shrinking effect the laser beam is target oriented and makes the surgical procedure safe without the use of additional instruments. The Nd-YAG laser was preferred in tumors with a rich vascular supply. Thus there was a definitely decreased need for blood transfusions in patients operated on with the laser. Even those parts of the tumors that can not easily be reached, using conventional techniques can now be eliminated by laser irradiation. The variable distance between the handpiece of the laser instrument and the target organ allows a pin point as well as a more diffuse irradiation. Since it is not necessary to touch the tissue, laser techniques are particularly useful in critical areas, e.g. close to the brainstem or the spinal cord, because they make it unnecessary to touch the tissue. The question as to whether the use of laser technique will reduce the rate of recurrent tumor growth needs further studies based on longer follow-up periods. Further technical improvements are needed to make the laser device a true microinstrument. Finally a combination of both laser types--that is the Nd-YAG laser for coagulation and the CO2 laser for cutting--might be a definite advantage.

Adolescent↗
PubMedDate not supplied

Living kidney donors' long-term psychological status and health behavior after nephrectomy - a retrospective study.

BACKGROUND: The aim of the study was a comprehensive psychological evaluation of living kidney donors. Existing studies indicate a high donor satisfaction with the decision to donate and good donor quality of life in short-term, as well as in long-term follow-up periods. In many studies, questionnaires with only a few items have been used to assess psychological health or well-being; however, most studies exclusively measured quality of life. Therefore, our retrospective single center study applied a broad assessment of psychological variables. We evaluated whether standardized, differentiated and specific psychological research instruments confirmed the positive, long-term condition of kidney donors as reported in the scientific literature, albeit based on a limited set of variables. METHODS: From 1973 to 2001, 152 nephrectomies were performed in Frankfurt. In the context of a detailed medical follow-up examination, a psychological study was implemented using a semi-structured interview and a set of four standardized, well-established questionnaires. Overall, data from 145 donors was included in the medical follow-up and 112 donors participated in the psychological investigation. RESULTS: The mean age of donors was 55.9 (+/- 10.7) yrs at follow-up, and the time-since-donation was 11.2 (+/- 7.5) yrs. Donors scored better on a wide range of the psychological scales such as psychological symptoms, health behavior and health consciousness that was to be expected in comparison with data from representative German population samples. Nearly all donors (97%) would choose to donate again, and 91% remain entirely satisfied with their decision. CONCLUSION: The study demonstrates that existing results, reporting positive long-term psychological donor well-being, could be confirmed by a set of comprehensive, standardized and multi-methodological psychological instruments.

Adult↗
PubMed1996

Factors affecting the cutting ability of sonic files.

The aim of this study was to investigate the cutting ability of sonic files. A model system was developed and the following variables evaluated: file type. Heliosonic or Shaper; file length, 21 or 29 mm; power, air inlet ring opening of half or fully open; stroke length, 2 or 4 mm; stroke rate, one or two cycles per second; and load 50 or 100 g. A 2(6) full-factorial analysis with two replications into the effect of the above variables on the cutting ability of the MM1500 sonic instrument was performed. A new size 25 file was used for each cut, together with water irrigation, and the substrate used was 1-mm thick sections of bovine bone. The differences between the variables were significant (ANOVA, P < 0.001). However, examination of the F-values showed that the most significant variable to affect cutting was load, followed by power, file type, stroke length and stroke rate, with the least significant variable being file length. The most significant interaction was between rate and length of stroke. An increase in stroke rate from one to two cycles per second at a stroke length of 2 mm produced an increase in cutting for both the Heliosonic and Shaper files. However, at the longer stroke length of 4 mm, the same increase in rate resulted in a decrease in cutting for the Shaper files. Therefore, it is suggested that operators should press the file against the canal wall and move it slowly to maximise cutting.

Analysis of Variance↗
PubMed1976

The "sick but slick" syndrome as a personality component of parents of battered children.

Thirteen parents convicted in court of battering their children and 13 matched controls were administered a battery of personality tests, with significant differences obtained on 5 of 21 study variables. Battering parents appeared healthier on those instruments based on content validity, where the social desirability of the items is more obvious. They appeared more disturbed (i.e., psychopathic) on items based on concurrent or statistical validity. It was concluded that battering parents were psychopathically disturbed, but whenever possible presented a distorted picture of themselves as healthy and unlikely to abuse their children. This tendency has been labeled the "sick but slick syndrome."

Antisocial Personality Disorder↗
PubMed2002

Functional assessment using Constant's Shoulder Scale after modified radical and selective neck dissection.

BACKGROUND: Constant's Shoulder Scale is a validated and widely applied instrument for assessment of shoulder function. We used this instrument to assess which treatment and demographic variables contribute to shoulder dysfunction after neck dissection in head and neck cancer patients. METHODS: A convenience sample of 54 patients with 64 neck dissections and minimum follow-up of 11 months were evaluated. Thirty-two accessory nerve-sparing modified radical (MRND) and 32 selective neck (SND) dissections were performed. Multivariable regression analysis was used to determine the variables that were predictive for shoulder dysfunction. Clinical variables included age, time from surgery, handedness, weight, radiation therapy, neck dissection type, tumor stage, and site. RESULTS: Patients receiving MRND had significantly worse shoulder function than patients with SND (p =.0007). Radiation therapy contributed negatively, whereas weight contributed positively (p =.0001). CONCLUSIONS: The critical factors contributing to shoulder dysfunction after neck dissection were weight, radiation therapy, and neck dissection type.

Female↗
PubMed1994

Maternal-fetal attachment: influence of mother-daughter and husband-wife relationships.

Intergenerational attachment relationships between the pregnant woman and her mother, her husband, and her fetus were examined. Self-completed instruments were used to measure the attachment variables for a convenience sample of 115 middle-class mothers who attended urban prenatal classes. Results supported the hypothesis that mother-daughter and husband-wife attachment were correlated positively. Contrary to study predictions, maternal-fetal attachment scores were not related to mother-daughter and husband-wife attachment scores. Maternal-fetal attachment was related to length of gestation. Results provide only partial support for the intergenerational model of attachment relationships.

Adult↗
PubMed1987

Prediction of therapeutic response in acute treatment with antidepressants. Results of an empirical study involving 159 endogenous depressive inpatients.

A study was carried out involving 159 endogenous depressive inpatients treated with antidepressants. Using standardized rating instruments, a large set of potential predictor variables was tested. After cross-validation according to the split-half technique, only very few of these proved to be suitable as predictors for the main outcome criteria. These predictors included premorbid maladjustment, neurotic traits of premorbid personality, intensity of depressive-apathetic symptoms at admission, and the self-evaluated mood assessment score 3 weeks after commencement of treatment. This last criterion demonstrated the highest predictive value. Several predictors known from the literature could not be reproduced in this study.

Adolescent↗
PubMed1993

Prediction of short-term outcome of neurotic-depressive inpatients. Results of an empirical study of 134 inpatients.

A study was carried out involving 134 neurotic-depressive inpatients (according to ICD-9) treated with cognitive behaviour therapy and in a subgroup additionally with antidepressants. Using standardized rating instruments, a large set of potential predictor variables was tested. After cross-validation according to the split-half technique, only very few of these proved to be suitable as predictors for the main outcome criteria. These predictors included certain aspects of social functioning before index admission, intensity of depressive symptoms at admission and the degree of self-evaluated mood disturbances three weeks after admission. Several predictors known from the literature could not be reproduced in this study, demonstrating the well-known instability of most predictor findings. On the other side, the predictor profile of the neurotic-depressive patients was quite similar to that found in endogenous depressives, a result which might--together with other findings, such as the response of neurotic depressives to antidepressants--question the traditional subclassification of functional depressive states into these subgroups.

Adolescent↗
PubMed2001

web-based interactive data processing: application to stable isotope metrology.

To address a fundamental need in stable isotope metrology, the National Institute of Standards and Technology (NIST) has established a web-based interactive data-processing system accessible through a common gateway interface (CGI) program on the internet site http://www. nist.gov/widps-co2. This is the first application of a web-based tool that improves the measurement traceability afforded by a series of NIST standard materials. Specifically, this tool promotes the proper usage of isotope reference materials (RMs) and improves the quality of reported data from extensive measurement networks. Through the International Atomic Energy Agency (IAEA), we have defined standard procedures for stable isotope measurement and data-processing, and have determined and applied consistent reference values for selected NIST and IAEA isotope RMs. Measurement data of samples and RMs are entered into specified fields on the web-based form. These data are submitted through the CGI program on a NIST Web server, where appropriate calculations are performed and results returned to the client. Several international laboratories have independently verified the accuracy of the procedures and algorithm for measurements of naturally occurring carbon-13 and oxygen-18 abundances and slightly enriched compositions up to approximately 150% relative to natural abundances. To conserve the use of the NIST RMs, users may determine value assignments for a secondary standard to be used in routine analysis. Users may also wish to validate proprietary algorithms embedded in their laboratory instrumentation, or specify the values of fundamental variables that are usually fixed in reduction algorithms to see the effect on the calculations. The results returned from the web-based tool are limited in quality only by the measurements themselves, and further value may be realized through the normalization function. When combined with stringent measurement protocols, two- to threefold improvements have been realized in the reproducibility of carbon-13 and oxygen-18 determinations across laboratories.

Journal Article↗
PubMed2000

The role of aminosalicylates at the beginning of the new millennium in the treatment of chronic inflammatory bowel disease.

OBJECTIVE: To discuss the pharmacological properties of aminosalicylates and their potential value in the treatment of chronic inflammatory bowel disease (IBD). METHODS: A review of clinical studies on the pharmacokinetics and mode of action of aminosalicylates is provided. In addition, the clinical efficacy and safety of aminosalicylates in the treatment of IBD, according to several recent meta-analyses, is summarised. RESULTS: Whereas aminosalicylates represent drugs of first choice in the acute treatment of ulcerative colitis and also for maintaining those patients in remission, their value for patients with Crohn's disease, either for achieving or maintaining remission, is at best modest. There is a large variability in the clinical results, especially in Crohn's disease, which is probably due to the variable extent and severity of IBD, different instruments in the evaluation of therapeutic outcome, and also at least partly caused by the different preparations and dosages of aminosalicylates used, as well as the high variation in drug disposition and topical availability of the active drug. The popular use of aminosalicylates is most likely due to the low incidence of side effects and the good overall safety records of mesalazine (mesalamine). CONCLUSIONS: Apparently, the full therapeutic potential of aminosalicylates has not yet been evaluated (e.g. upper dosage range, combination therapy, responding subgroups). Consequently, the imperfect treatment might be improved in the new millennium by novel insights in the complex mode of action of mesalazine as well as in the etiopathogenesis of IBD.

Aminosalicylic Acids↗
PubMed2000

Use of arterial oxygen saturation, heart rate, and blood pressure as indirect objective physiologic markers to predict aspiration.

If an indirect bedside variable can reliably predict whether an objective instrumental dysphagia evaluation is needed, time and money can be saved without compromising patient care. To date, the search for a reliable indirect subjective marker of aspiration has not been successful. However, research on indirect objective markers of aspiration is alluring. The purpose of the present study was to investigate changes, if any, in the physiologic parameters of arterial oxygen saturation (SpO(2)), heart rate, and blood pressure during simultaneous objective confirmation of aspiration status with Fiberoptic Endoscopic Evaluation of Swallowing (FEES). Sixty adult subjects were divided into 4 groups of 15. Group 1 did not require supplemental oxygen and did not aspirate. Group 2 did not require supplemental oxygen and exhibited aspiration. Group 3 required supplemental oxygen and did not aspirate. Group 4 required supplemental oxygen and exhibited aspiration. Simultaneous SpO(2), heart rate, and blood pressure measurements were collected at 1-min intervals, i.e., pre-FEES baseline for 5 min; during FEES; and post-FEES for 5 min. Results indicated no significant differences in SpO(2) levels based on aspiration status or oxygen requirements for any of the 4 groups. A consistent pattern of higher heart rate values during FEES and continuing for 5 min post-FEES was observed for all 4 groups. A consistent pattern of higher blood pressure values during FEES and then lower blood pressure values post-FEES was observed for all 4 groups. It was concluded that the use of changes in SpO(2), heart rate, or blood pressure values as indirect objective markers of aspiration was not supported.

Adult↗
PubMed1989

Acute physiologic and perceptual responses during three modes of ambulation: walking, axillary crutch walking, and running.

This study compared the acute physiologic responses during three modes of ambulation--walking, axillary crutch walking (ACW), and running. Twelve healthy women volunteered to ambulate for one kilometer at their self-selected speeds for each of the three activities. Before the ACW test, the subjects completed one or two training sessions to familiarize themselves with this mode of ambulation. Standardized instruments were used to monitor the cardiorespiratory variables, and perceptual responses were recorded using the Borg scale for ratings of perceived exertion (RPE). The results indicated that walking was the least stressful of the three activities. Comparisons between ACW and running revealed that although the steady-state heart rate and minute oxygen consumption were significantly higher during running (173.5 vs 168.6 beats/min and 2.05 vs 1.06 L/min for running and ACW, respectively), the net metabolic cost per unit distance traveled was significantly higher during ACW (1.77 vs 1.01 kcal/kg/km) because of the longer time taken to ambulate the one-kilometer distance. The other variables studied--the oxygen pulse, ventilatory equivalent for oxygen, and RPE--also clearly indicated that ACW was the most stressful activity. Based on these limited observations, it is suggested that special precautions be taken when prescribing axillary crutches to women who have significant cardiorespiratory problems but are unaware of them, or to cardiac patients because of their coronary insufficiency.

Adult↗
PubMed1994

Epidural anesthesia in early compared with advanced labor.

OBJECTIVES: To examine whether continuous lumbar epidural analgesia administered in the early phase of labor leads to an increased incidence of instrumental vaginal deliveries. METHODS: In a retrospective analysis we have studied 563 consecutive term cephalic vaginal deliveries where an epidural was given for pain relief in labor. The type of delivery was compared in two groups. In Group 1 epidurals were given when the cervix was 3 cm or less dilated; in Group 2 when they were greater than 3 cm dilated. RESULTS: There was no difference in the incidence of instrumental deliveries in the two groups. Other variables including station of the fetal head, premature rupture of membranes, meconium, and administration of pitocin and pethidine did not effect these results. CONCLUSIONS: There is no justification in delaying epidural analgesia in labor when it is clinically indicated.

Anesthesia, Epidural↗
PubMed1981

The hysterophore: a new instrument for uterine manipulation during laparoscopy.

The hysterophore was developed for moving the uterus around during laparoscopy. The instrument provides an intra-uterine sound variable in length and direction, fixed to the cervix by a sliding cup. Especially in cases of a large retroverted uterus or multiple pelvic adhesions the hysterophore can place the uterus in a safe position for sterilization procedures.

Female↗
PubMed1994

Guidelines for experimental studies.

OBJECTIVES: The purpose of this document is to present guidelines for the training of researchers and for the planning of experiments that ensure optimum interaction and communication among the investigators and statisticians of the research team. METHODS: The protocol described in this document is designed to systematically guide a researcher through a sequence of planning steps and checkpoints to ensure proper experimental design, data management, statistical analyses, and interpretation. RESULTS: The investigator and the statistician, as a collaborative team, will be able to determine the most effective and appropriate procedures and tools necessary for the successful completion of a research project. SIGNIFICANCE: Planning an experimental study necessitates much thought. Lack of essential communication with a statistician in the initial stages of the experimental design can doom the experiment to failure. Flawed research studies may be associated with one or more of the following: failure of the established testable hypothesis, uncontrolled biases, insufficient sample size, lack of appropriate controls, variability in specimen preparation, improper calibration of instruments or standardization of measurements, incorrect data entries, inappropriate statistical analyses, errors in interpretation of statistical analyses, and erroneously drawn conclusions. Standard guidelines will eliminate many of these potential problems.

Data Collection↗
PubMed1985

Construction and performance of a variable-frequency phase-modulation fluorometer.

We describe the construction and performance of a variable-frequency phase-modulation fluorometer. This instrument, which provides modulation frequencies from 1 to 200 MHz, was constructed using commercially available components. To facilitate the introduction of these instruments into other laboratories we describe in detail the chosen components and the principles of operation. The present light source is a continuous-wave helium-cadmium laser, which provides convenient excitation wavelengths of 325 and 442 nm. Modulation of the incident light is provided by one of several electro-optic modulators. The extent of modulation ranges from 1.0 to 0.2 as the frequency increases from 1 to 200 MHz. Phase angles and demodulation factors are measured using the cross-correlation method. The closely spaced frequencies are provided by two direct frequency synthesizers. The phase and modulation measurements are accurate to 0.2 degrees and 0.002, respectively, from 1 to 200 MHz. This accuracy allows considerable resolution of complex decay laws. The usefulness of frequency-domain fluorometry for the resolution of multiexponential decays is illustrated by the analysis of several difficult mixtures. As examples, we resolved a two-component mixture of anthracene (4.1 ns) and 9,10-diphenylanthracene (6.3 ns), and confirmed that the intensity decay of NADH in aqueous buffer is at least a double exponential (0.2 and 0.86 ns). We also resolved an especially difficult mixture of anthracene (4.1 ns) and 9-methylanthracene (4.5 ns), and a three-component mixture with decay times of 1.3, 4.1 and 7.7 ns. Frequency-domain fluorometers appear to be particularly useful for determination of complex decays of fluorescence anisotropy. This capability is illustrated by the determination of rotational correlation times as short as 47 ps for p-bis[2-(5-phenyloxazolyl)]benzene (POPOP) in hexane at 40 degrees C, and by the resolution of the two correlation times of anisotropic rotators such as perylene and 9-aminoacridine. Resolution of two anisotropy decay times for 9-aminoacridine is a difficult test because these correlation times differ by less than 2-fold. The resolution of multiexponential decays of intensity and anisotropy possible with this instrument is at least equivalent to that obtained using state-of-the-art time-resolved instruments based on mode-locked laser sources. The ease and rapidity of frequency-domain measurements, the relative simplicity of the equipment, the accuracy of the measurements and the lack of significant systematic errors indicate that frequency-domain fluorometry will be widely useful in chemical and biochemical research.

Aminoacridines↗
PubMed1989

Sources of variability for Doppler color flow mapping of regurgitant jets in an animal model of mitral regurgitation.

To determine whether Doppler color flow mapping could be used to quantify changing levels of regurgitant flow and define the technical variables that influence the size of color flow images of regurgitant jets, nine stable hemodynamic states of mitral insufficiency were studied in four open chest sheep with regurgitant orifices of known size. The magnitude of mitral regurgitation was altered by phenylephrine infusion. Several technical variables, including the type of color flow instrument (Irex Aloka 880 versus Toshiba SSH65A), transducer frequency, pulse repetition frequency and gain level, were studied. Significant increases in the color flow area, but not in color jet width measurements, were seen after phenylephrine infusion for each regurgitant orifice. For matched levels of mitral regurgitation, an increase in gain resulted in a 125% increase in color flow area. An increase in the pulse repetition and transducer frequencies resulted in a 36% reduction and a 28% increase in color flow area, respectively. Jet area for matched regurgitant volumes was larger on the Toshiba compared with the Aloka instrument (5.2 +/- 3.1 versus 3.2 +/- 1.2 cm2, p less than 0.05). Color flow imaging of mitral regurgitant jets is dependent on various technical factors and the magnitude of regurgitation. Once these are standardized for a given patient, the measurement of color flow jet area may provide a means of making serial estimates of the severity of mitral insufficiency.

Animals↗