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Biomedical subjects

J F Huber

Publications and source records attributed to J F Huber.

34 records · Page 2Linked to original sources
PubMed1977

Improvement of the efficiency of ion-exchange cellulose columns and their application.

Packing procedures and operating conditions for microparticulate ion-exchange cellulose columns were investigated. The efficiencies of ion-exchange cellulose and mixed-bed ion-exchange cellulose columns were compared. The mixed-bed columns contained ion-exchange cellulose and diatomite, and those with a 5:1 volume ratio of ion-exchange cellulose (average particle size 7 micronm) and diatomite were found to be superior in almost every respect. Medical, pharmaceutical, biochemical and environmental applications of this type of column are shown.

Cellulose↗
PubMed1977

Separation of estrogen glucorinides, sulphates and phosphates on ion-exchange cellulose by high-pressure liquid chromatography.

In continuation of previous work, the selectivity of anion-exchange cellulose systems with respect to thirty estrogen conjugates was studied. The influence of the type and particle size of cellulose anion exchangers, the type and concentration of the counter anion, pH and temperature was investigated. On the basis of the results the optimal choice of the ion-exchange material, the eluent and the operating conditions is demonstrated. The results of the optimization are exemplified by a number of chromatograms showing rapid separations, including the determination of the estrogen conjugate profile of human pregnancy urine.

Cellulose↗
PubMed1977

Rapid trace analysis of barbiturates in blood and saliva by high-pressure liquid chromatography.

The performances of a number of liquid--solid systems, consisting of mixtures of water and methanol as liquid phase and methyl silica as solid phase, were investigated with respect to their use in the separation of barbiturates by high-pressure liquid chromatography (HPLC). Phase system selectivities and column efficiencies were determined. The results were applied to the development of a rapid method for the determination of trace amounts of barbiturates in blood. The first step in the analysis, the extraction of barbiturates from blood, was also investigated and good recoveries were achieved. The extracts were analyzed by HPLC using ultraviolet detection at 220 nm. A low detection limit and high precision were obtained; An amount of 5 ng hexobarbital, for example, can be determined with a precision of +/-15% and 5 mug with a precision of +/-0.3%. The time course of the concentration of hexobarbital in the serum and saliva of man after an oral administration of 400 mg is demonstrated.

Autoanalysis↗
PubMedDate not supplied

[Optimizing primary total hip replacement--a technique to effect saving of manpower].

PURPOSE: Development of a standardized surgical technique for total hip replacement thereby saving manpower (one assistant) by using a retractor system. METHOD: Total hip replacement is performed with the patient in a true lateral position on a tunnel cushion. By means of a direct lateral approach the pelvitrochanteric muscles are partially detached using an omega-shaped cut. The Bookwalter retractor is fixed dorsally on the operating table. The ring is centered keeping the greater trochanter in the middle. The Hohmann retractors are fixed to the ring to sufficiently expose the acetabulum. To insert the femoral stem the ring needs to be opened dorsally and the patient's leg is bent 90 degrees in the hip and the knee over the tunnel cushion. The muscles inserting at the greater trochanter are retracted by a separate Hohmann retractor with weight. In a case control study with matched pairs the patients treated with this technique were compared with those treated in supine position with the transgluteal approach. The number of assistants required and the operating time were assessed. RESULTS: All the hip replacements with the patient in side position were performed with one assistant, in supine position with two assistants. The operating time did not differ significantly (supine position 110 min/side position 112 min). The complication rate in both groups was comparable (one secondary wound healing, one transient ischalgia). CONCLUSION: The process of total hip replacement can be optimized. The described technique allows to spare one surgical assistant without prolonging the operating time.

Appointments and Schedules↗
PubMedDate not supplied

[Clinical results 2 years after total hip replacement (WOMAC/SF-36) and comparison with the normal population (SF-36)].

AIM: The aim of this study was to determine the outcome after total hip replacement (THR) with the WOMAC and the SF-36 as well as to identify the most responsive items and to elucidate the reasons for increased pain postoperatively. METHODS: 73 patients filled out the questionnaires preoperatively and 3, 6, 12, 24 months postoperatively. All mean subscales and the responsiveness for each question were calculated. The patients with increased pain postoperatively were reassessed. RESULTS: All WOMAC subscales and six of the eight SF-36 subscales showed significant improvements after THR (p < 0.05). The most responsive items were the pain and disability questions (SRM, ES > 1.5). Two patients with a higher pain score postoperatively had associated symptomatic degenerative lumbar spinal disease. CONCLUSIONS: The WOMAC and the SF-36 are valid measures of the outcomes of THR in their German translations and document the good results after THR. Two years after THR the patients reach the same health state compared to an age matched control group in the population. The WOMAC contains more questions of higher responsiveness than the SF-36. A higher pain score postoperatively may be caused by degenerative disease of the lumbar spine.

Activities of Daily Living↗
PubMedDate not supplied

Determination of 1,2,4-trimethylbenzene (pseudocumene) in serum of a person exposed to liquid scintillation counting solutions by GC/MS.

1,2,4-Trimethylbenzene (pseudocumene) is often used as the solvent for liquid scintillation counting solutions. In the present work, the determination of 1,2,4-trimethylbenzene in the serum of a person exposed to the solvent vapor during the handling of liquid scintillation counting cocktails is described. The identification of 1,2,4-trimethylbenzene was carried out by GC/MS. The analyte was quantified by GC with flame ionization detection. The detection limit of the method is 0.01 ppm. Two hours after exposure of a person to the solvent vapor, the concentration of 1,2,4-trimethylbenzene in her serum was found to be 0.20 ppm.

Benzene Derivatives↗