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B Dahl

Publications and source records attributed to B Dahl.

At least 19 recordsLinked to original sources
PubMed1998

Self-reported need of information, counselling and education: needs and interests of re-applicants.

An interview study was performed to establish and evaluate the need for education and counselling of hearing aid users (HA users) in order to review present procedures of information and potential referral to the educational sector. The study comprises 102 consecutively selected hearing-impaired adults (>18 years), the only inclusion criterion being experienced HA user. The interview took place immediately after the patient's latest HA fitting appointment and consisted of 24 structured and closed questions. The findings indicate that a significant proportion of HA users, especially the elderly, do not experience a need for or show an interest in further education and counselling concerning their hearing handicap. It is concluded that the present organization of services meets the demands of a majority of re-applicants.

Adult↗
PubMed1998

Comparison of the levels of quality of inpatient care delivered by pediatrics residents and by private, community pediatricians at one hospital.

PURPOSE: To compare the quality and cost of inpatient care provided by pediatrics residents with the quality and cost of that provided by private, practicing pediatricians. METHOD: Valley Children's Hospital--a 175-bed, private, nonprofit, university-affiliated pediatric hospital located in Fresno, California--has both a resident service and a community physician service. From May 1994 to March 1995 a total of 154 pediatric patients (64 from the resident service, 90 from the community service) were selected for the study using incidental sampling. In order to be included in the study, patients had discharge diagnoses of uncomplicated gastroenteritis or asthma. The parent or guardian of each patient completed a satisfaction questionnaire at discharge and agreed to a home visit one month later, when the same questionnaire and another were completed. Patients' charts were studied for treatment procedures, and follow-up data for a year were compiled. Statistical analyses were conducted with analysis of variance for continuous measures and chi-squares for dichotomous variables. RESULTS: The findings indicated no difference between the two services in terms of the parents' and guardians' satisfaction with patient care, hospital charges, and degrees of adherence to follow-up care after discharge. The community physicians were more likely than were the residents to employ non-standard laboratory and management procedures with both the asthma and gastroenteritis patients. The asthma patients cared for by community physicians had significantly more frequent asthma attacks after discharge, with a higher frequency of patients being subsequently treated in the emergency room and readmitted to the hospital, than did the asthma patients cared for by the residents. CONCLUSION: Common perceptions that physicians-in-training (1) overuse medical services and (2) fail, due to their inexperience, to provide high-quality services were not supported in this study.

Adolescent↗
PubMed1998

Serum Gc-globulin in the early course of multiple trauma.

OBJECTIVES: In patients with multiple trauma, actin released from damaged cells may cause severe circulatory disturbance due to thrombi formation. The aim of this study was to evaluate serum concentrations of the actin scavenger, Gc-globulin, in relation to the severity of injury and outcome. DESIGN: Prospective, longitudinal, observational study. SETTING: Trauma center at a university hospital. PATIENTS: Twelve patients with multiple trauma, consecutively included, according to defined criteria. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Serum Gc-globulin concentrations were measured at the time of admission and daily thereafter for 1 wk or until death. In all patients, the Gc-globulin concentration was significantly low (p < .0001), and the proportion of Gc-globulin bound to actin was already increased compared with normal values (p < .0001) by the time of hospital arrival. There was an inverse correlation between the mean concentration of serum Gc-globulin in the first week after trauma and the Injury Severity Score (r = -0.72, p < .05). Surviving patients had a significantly (p < .05) higher concentration of serum Gc-globulin in the first week after trauma compared with nonsurvivors. CONCLUSIONS: Serum concentrations of Gc-globulin were significantly low in trauma patients. The reduction took place within 60 mins after injury. Because the normal half-life of Gc-globulin is almost 48 hrs, our observations suggest a marked consumption of Gc-globulin immediately after the trauma. This finding could be the first clinical evidence that Gc-globulin plays a role in the systemic inflammatory response syndrome after trauma. This result is supported by the finding that lack of Gc-globulin was related to nonsurvival and the severity of the trauma.

Actins↗
PubMed1997

Clinical outcome after spinal fusion with a rigid versus a semi-rigid pedicle screw system.

Several biomechanical studies have evaluated the quality of fusion obtained with a rigid versus a semi-rigid pedicle screw implant. Some studies indicate that increased rigidity of the implant system results in an increased strength of the fusion mass. Other reports have underlined the risk of stress shielding due to rigid implant systems. Based on these findings some authors have recommended the use of a semi-rigid system. There are, however, few studies focusing on any possible difference in clinical outcome between the two different types of implant systems. Questionnaires were sent to 89 patients who had undergone primary spinal fusion with either a rigid or a semi-rigid pedicle-screw-based implant system. In every case the diagnosis was spondylolisthesis or degenerative lumbar disease. The questionnaires were analysed using forward stepwise logistic regression analysis. Eighty (90%) of the questionnaires were returned. There was a mean follow-up of 4 years (range 2-8 years). It was not possible to demonstrate any difference in clinical outcome between patients undergoing lumbar fusion with a rigid implant system and those given a semi-rigid system. The overall patient satisfaction rate was 69%, with no difference between the two types of implant. No difference in clinical outcome between the two types of implant was found. Considering the fact that the primary goal of spinal fusion procedure is to obtain a solid fusion mass, biomechanical tests favour the used of a rigid pedicle screw system. This fact combined with the fact that early mobilisation is possible with rigid implants justifies the use of rigid implant systems, although no difference in clinical outcome could be demonstrated in this study.

Adolescent↗
PubMed1997

A validational study of the Structured Interview of Symptoms Associated with Sexual Abuse (SASA) using three samples of sexually abused, allegedly abused, and nonabused boys.

OBJECTIVE: With the rapid rise of sexual abuse allegations, there is a growing need to develop instruments to help clinicians determine the likelihood that sexual abuse has occurred. METHOD: This study evaluated the discriminant validity of a structured parent interview regarding emotional, behavioral, and physical symptoms by comparing results among three subsamples of age matched boys: 22 sexually abused boys whose perpetrator confessed, 47 boys evaluated in a sexual abuse clinic but without a history of perpetrator confession and 52 nonabused boys selected after rigorous screening. RESULTS: In comparison with the nonabused (NA) boys, the sexually abused boys were significantly more likely to demonstrate sudden emotional and behavioral changes, frequent stomach aches, more knowledge about sex and sexual activities than expected for age, unusual aggressiveness toward playmate or toy's private parts, crying easily, difficulty getting to sleep, and a change to poor school performance. The internal reliability of the SASA was determined to be .83 and scoring of an abbreviated 12-item scale demonstrated a sensitivity of 90.9% and a specificity of 88.5%. CONCLUSIONS: The findings suggest that Structured Interview of Symptoms Associated with Sexual Abuse (SASA) is an effective tool which may help in the comprehensive assessment of boys who may have been sexually abused.

Adolescent↗
PubMed1996

Inhibition of a Src homology 2 domain containing protein tyrosine phosphatase by vanadate in the primary culture of hepatocytes.

Inhibition of protein tyrosine phosphatase (PTP) activities by vanadate was examined in cultured rat hepatocytes. The incubation of hepatocytes with sodium orthovanadate inhibited PTP activities, measured with labeled polyglutamate tyrosine (4:1) and insulin receptor peptide (1142-1153), in a dose- and time-dependent manner. The PTP activities in cytosolic and particulate fractions were inhibited with the IC50 values of 30-50 and 2-20 microM, respectively. Vanadate-mediated inhibition of protein phosphatase, type 1 (a serine phosphatase) was less pronounced, requiring 50- to 150-fold higher concentrations. Molybdate and tungstate, the other potent inhibitors of PTPs, exerted approximately 70% less inhibition of enzyme activities compared to vanadate in intact liver cells. The cytosolic and particulate PTPs inhibited by vanadate were further resolved by fast protein liquid chromatography on Mono Q and Superose-12 columns. Vanadate exerted stable and differential inhibition of several PTPs. One of them was identified as SHPTP2 (Syp, SHP-2) in cytosolic as well as particulate fractions. Immunoprecipitation of this PTP with Syp-antibody coupled to protein A-agarose confirmed the vanadate-induced decrease in SHPTP2 activity. Vanadate did not alter the expression of SHPTP2 and its distribution between cytosolic and particulate fractions as indicated by the immunoblots. The decrease in the activities of PTPs in vanadate-treated hepatocytes in general was found to be reversed by the reducing agent dithioerythreitol. This study shows that vanadate inhibits many PTPs in intact liver cells, one of them being SHPTP2/SHP-2. The inhibition is stable after chromatography on ion-exchange and gel filtration chromatography. The enzyme inhibition seems to involve the oxidation of the thiol group of PTPs.

Animals↗
PubMed1996

CO(2) and indomethacin vasoreactivity in patients with head injury.

The purpose of this study was to compare the effect of hyperventilation and indomethacin on cerebral circulation, metabolism and pressures in patients with acute severe head injury in order to see if indomethacin may act supplementary to hyperventilation. Fourteen severely head injured patients entered the study. Intracranial pressure (ICP), mean arterial blood pressure (MABP) and cerebral perfusion pressure (CPP) were monitored continuously. Within the first four days after the trauma the CO(2) and indomethacin vasoreactivities were studied by measurements of cerebral blood flow (CBF) (Cerebrograph 10a, intravenous (133)Xe technique) and arterio-venous difference of oxygen (AVdO(2)). Ischaemia was evaluated from changes in CBF, saturation of oxygen in the jugular bulb (SvjO(2)), lactate and lactate/oxygen index (LOI). Data are presented as medians and ranges, results are significant unless otherwise indicated. Before intervention ICP was well controlled ,(14.8 (9-24) mmHg) and basic CBF level was 39.1 (21.6-75.0) ml/100 g/min). The arterio-venous oxygen differences were generally decreased (AVdO(2) = 4.3 (1.8-8.1) ml/100 ml) indicating moderate luxury perfusion. Levels of CMRO(2) were decreased (1.54 (0.7-3.2) ml/100 g/min) as well. During hyperventilation (delta PaCO(2)=0.88 (0.62-1.55) kPa) CBF decreased with 11.8 (-33.4-29.7) %/kPa and ICP decreased with 3.8 (0-10) mmHg. AVdO(2) increased 34.0 (4.0-139.2) %/kPa, MABP was unchanged, CMRO(2) and CPP increased (delta CPP = 3.9 (-10-20) mmHg). AVD (lactate) and LOI were unchanged. No correlations between CBF responses to hypocapnia and outcomes were observed. An i.v. bolus dose of indomethacin (30 mg) decreased CBF 14.7 (-16.7-57.4)% and ICP decreased 4.3 (-1-17) mmHg. AVdO(2) increased 27.8 (-40.0-66.7)%, MABP (delta MABP = 4.9 (-2-21) mmHg) and CPP (delta CPP = 8.7 (3-29) mmHg) increased while CMRO2 was unchanged. No changes in AVd (lactate) and LOI indicating cerebral ischaemia were found. Compared to hyperventilation (changes per 1 kPa, at PaCO(2) level = 4.05 kPa) the changes in MABP, CPP and CBF were significantly greater after indomethacin, while the changes in AVdO(2), ICP, SvjO(2) and LOI were of the same order of magnitude. No correlation between relative reactivities to indomethacin and CO(2), evaluated from changes in CBF and AVdO(2), or between the decrease in ICP after the two procedures were found. Thus, some patients reacted to indomethacin but not to hyperventilation, and vice versa. These results suggest that indomethacin and hyperventilation might act independently, or in a complementary fashion in the treatment of patients with severe head injury.

Adult↗
PubMed1996

Predictors of 10-year macrovascular and overall mortality in patients with NIDDM: the Munich General Practitioner Project.

The 10-year follow-up of the Munich General Practitioner Project was designed as a long-term prospective study to evaluate factors predicting macrovascular and overall mortality in a random cohort of non-insulin-dependent diabetic (NIDDM) patients. Of the original 290 patients (103 males, 187 females, median age 65 years) 92.5% could be assessed, 103 subjects had died, 58 from macrovascular causes. In an univariate analysis of baseline data, deceased patients, and especially those who died from macrovascular causes had significantly higher fasting blood glucose, HbA1c, von Willebrand-factor protein, urine albumin excretion, and serum beta 2-microglobulin, were significantly older, exhibited significantly more ischaemic heart disease (abnormal ECG Minnesota codes), carotid artery and peripheral vascular disease (both determined by ultrasound-Doppler), and had significantly inferior knowledge about diabetes and its treatment. No significant differences were seen for gender, blood pressure, smoking, total cholesterol, triglycerides, HDL-cholesterol, or the use of antidiabetic, antihypertensive or coronary drugs. In a multiple logistic regression analysis, the risk factors for macrovascular death were age, HbA1c and von Willebrand-factor protein. When baseline macrovascular disease was taken into account, carotid artery disease was also a determinant. The main variables from the metabolic syndrome (blood pressure, dyslipidaemia, body mass index) did not enter a multiple logistic regression analysis. The data suggest that age and haemoglobin A1c are major determinants, and that in addition von Willebrand-factor associated endothelial damage is a risk factor for macrovascular mortality in NIDDM patients.

Age Factors↗
PubMed1995

[Pregnancy and delivery in a woman with neuromuscular disease. Spinal muscular atrophy and severely reduced pulmonary function].

Pregnancy and delivery are described in a 22-year-old woman suffering from spinal muscular atrophy. In spite of severe respiratory insufficiency with a vital capacity of 0.6 litre, pregnancy and planned caesarean section in general anaesthesia went without complications. Some explanations for this are presented. Teams involving respiratory centres specialized in the treatment of patients with neuromuscular diseases, obstetricians and neurologists are recommended. These teams may carry out individual counselling, frequent controls, respiratory support and planning of delivery.

Adult↗
PubMed1995

Functional and social long-term results after free tissue transfer to the lower extremity.

We report the long-term social and functional results in 53 patients receiving free tissue transfer after trauma to the lower extremity. The results are compared with those of a matched group of patients receiving primary amputation. The microsurgically treated patients had significantly more complaints over pain during walk (p = 0.02) and edema (p < 0.00005). Regarding social results, no significant differences between the two groups were found. Time until surgery, infection, or bone defect before free flap surgery did not alter the overall results significantly. It is concluded that the long-term functional and social results after free tissue transfer are almost the same as those achieved after simple amputation. Because the median time until free flap surgery in this series was 158 days, early limb-saving procedures could possibly improve the long-term results.

Adult↗
PubMed1993

The relationship between inert gas wash-out and radioactive tracer microspheres in measurement of bone blood flow: effect of decreased arterial supply and venous congestion on bone blood flow in an animal model.

Several methods have been employed in the study of bone perfusion. We used a method of determining inert gas wash-out by mass spectrometry in the study of blood flow rates in pigs. The method was validated by comparison of the result obtained with inert gas wash-out to that with measurement by microspheres. Furthermore, the effect of decreased inlet flow and venous congestion on the bone perfusion data was tested. The undisturbed bone blood flow was not significantly different when measured with wash-out of inert gas (7 +/- 0.7 ml/min/100 g) or with microspheres (9 +/- 2.9 ml/min/100 g), and the methods were correlated. Perfusion was reduced significantly, to 20% of the original value, after arterial occlusion. The changes in wash-out curves and accumulation of radioactive tracer provided substantial evidence for impaired intraosseous circulation following venous obstruction also. In conclusion, the study showed that this method of determining inert gas wash-out is feasible for studies of local perfusion rates in bone. The flow rates obtained by wash-out correlated well with the results of microsphere studies. In this animal model, both methods detected a fivefold reduction in flow rate after clamping of the arterial inflow. Obstruction of the venous outflow also impaired blood flow and lowered the cellular supply.

Animals↗
PubMed1993

Laser Doppler flowmetry for estimation of bone blood flow: studies of reproducibility and correlation with microsphere technique.

The blood flow in the femoral condyles of six pigs was measured by the microsphere technique and by laser Doppler flowmetry (LDF) before and after clamping of the external iliac artery. A significant decrease in the bone blood flow was found with both microsphere and LDF measurements, and a high correlation was found between the two methods. After release of the arterial clamp, the LDF values rapidly returned to approximately the same values as before clamping. In a second part of the study, the LDF output signal was studied in the intertrochanteric area of eight patients. The reproducibility of two LDF measurements at the same location was within 15%. The temporal variability of the LDF signal during 10 min of recording showed only slight variations. It is concluded that LDF is relative in nature and that the mean LDF output signal is suitable for monitoring dynamic responses of the bone blood flow to various stimuli. Several consecutive measurements have to be performed if the blood flow at different locations of a specific bone are to be compared with each other.

Animals↗
PubMed1992

[Oxygen conserving nasal catheters. Oxymizer pendant].

The Oxymizer pendant consists of a 40 ml pendulating reservoir bag which is connected to the prongs by two tubes. Both reservoir and tubes serve as oxygen reservoirs. We wanted to examine if it was possible to save oxygen by changing from the usual nasal cannula to Oxymizer pendant. 11 patients with hypoxaemia due to chronic obstructive pulmonary disease were examined. We were able to reduce the oxygen requirement by approximately 65% without significant changes in SaO2. All 11 patients evaluated the Oxymizer pendant to be more comfortable than the usual nasal cannula.

Catheterization↗
PubMed1992

Partial pressures of oxygen and carbon dioxide in bone and their correlation with bone-blood flow: effect of decreased arterial supply and venous congestion on intraosseous oxygen and carbon dioxide in an animal model.

Pathological changes in bone have been related to a preceding impediment of the arterial or venous bone circulation and hypoxia. In this study, we analyzed the feasibility of mass spectrometry in measuring intraosseous oxygen and carbon dioxide. The partial pressures were also measured in intraosseous blood samples, and blood flow in bone was measured with the radioactive microspheres technique. The average partial pressure of oxygen in the lateral femoral condyle was 34 +/- 1.6 mm Hg when measured in intraosseous blood samples and 36.3 +/- 2.3 mm Hg when measured with the on-line mass spectrometer, with significant correlation between the methods. The absolute value of the partial pressure of carbon dioxide measured in situ with mass spectrometry was correlated with the value in the withdrawn blood. There was no significant difference in partial pressures of oxygen and carbon dioxide between the two sides or between repetitive measurements. Arterial occlusion resulted in severe hypoxia, whereas more moderate changes followed venous occlusion.

Animals↗
PubMed1991

Older's classification of Colles' fractures. Good intraobserver and interobserver reproducibility in 185 cases.

To evaluate the reliability of the Older classification, 4 observers classified 185 distal radius fractures twice with 1 month's interval. Both the intraobserver agreement and the interobserver agreement were high, with kappa values of 0.75 (0.69-0.79) and 0.69 (0.60-0.77), respectively. The agreement was especially high for type 1 and type 4 fractures. Older's method of classifying distal radius fractures can thus be recommended for clinical use.

Colles' Fracture↗
PubMed1990

Characterization of rat brain NCAM mRNA using DNA oligonucleotide probes.

A number of different isoforms of the neural cell adhesion molecule (NCAM) have been identified. The difference between these is due to alternative splicing of a single NCAM gene. In rat brain NCAM mRNAs with sizes of 7.4, 6.7, 5.2, 4.3 and 2.9 kb have been reported. We have synthesized six DNA oligonucleotides, that hybridize to different exons in the NCAM gene. Furthermore we have constructed three oligonucleotides, that exclusively hybridize to mRNAs lacking certain exons, by letting them consist of sequences adjacent to both sides of the splice sites. By means of these probes we have characterized the five NCAM mRNAs in rat brain.

Animals↗
PubMed1990

The possible use of a spallation neutron source for neutron capture therapy with epithermal neutrons.

Spallation is induced in a heavy material by 72-MeV protons. The resulting neutrons can be characterized by an evaporation spectrum with a peak energy of less than 2 MeV. The neutrons are moderated in two steps: first in iron and then in carbon. Results from neutron fluence measurements in a perspex phantom placed close to the moderator are presented. Monte Carlo calculations of neutron fluence in a water phantom are also presented under some chosen configurations of spallation source and moderator. The calculations and measurements are in good agreement and show that, for proton currents of less than 0.5 mA, useful thermal-neutron fluences are attainable in the depth of the brain. However, the dose contribution from the unavoidable gamma background component has not been included in the present investigation.

Boron↗