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T Iversen

Publications and source records attributed to T Iversen.

At least 37 records · Page 2Linked to original sources
PubMed1994

IS1032 from Acetobacter xylinum, a new mobile insertion sequence.

IS1031 elements constitute a family of related insertion sequences (IS) in Acetobacter xylinum strains. A new IS1031-related element, IS1032, was isolated from A. xylinum ATCC 23770. Southern hybridization analysis showed that one or more sequences similar to IS1032 are present in most of the A. xylinum strains examined. In addition, one copy was detected in Acetobacter aceti ATCC 15973. The transposition of IS1032 was evident from the appearance of an extra insertion in a spontaneous exopolysaccharide-negative mutant of A. xylinum ATCC 23770. IS1032 consists of 916 bp and has imperfect terminal inverted repeats of 14 bp (IR-Left) and 16 bp (IR-Right). A 3-bp target sequence is duplicated upon insertion. IS1032 displays a single open reading frame, encoding a putative 276-amino-acid protein sharing 58% identity with the corresponding protein encoded by IS1031. Thus, IS1032 is a member of the IS1031 family in A. xylinum. A striking degree of nucleotide sequence similarity between IS1032 and ISRm4 from Rhizobium meliloti was found. Furthermore, the IS1031-family transposases also display stretches of amino acid sequence similarities with putative transposases encoded by IS elements from other species.

Amino Acid Sequence↗
PubMed1993

A theory of hospital waiting lists.

The noncooperative character of resource allocation in a national health service may contribute to excessive waiting lists. A theory of hospital waiting lists is derived from this idea. Waiting lists imply loss of efficiency; the hospital's resources are drawn away from medical work. Although there is scope for Pareto improvements, the structure of budget allocation may prevent these improvements from being achieved. Some reforms of the institutional structure are suggested.

Budgets↗
PubMed1993

Radiation-induced insufficiency fractures of the sacrum: evaluation with MR imaging.

In patients with malignant pelvic tumors, radiation-induced insufficiency fractures of the sacrum may be mistaken for metastasis. Magnetic resonance (MR) imaging was performed in 18 patients with this condition, and the findings were studied retrospectively. The diagnosis was confirmed with at least one additional imaging modality in 16 patients, whereas the other two patients underwent clinical follow-up at 13 and 20 months without evidence of metastasis. In 17 patients, the lesions were consistent with edema and had diffuse low signal intensity on T1-weighted images and diffuse high signal intensity on short-inversion-time inversion-recovery images, thereby simulating metastasis. In one patient, bilateral sacral wing fractures were demonstrated directly as fairly well-defined linear zones. The alae sacri were involved in all patients; 16 patients had bilateral lesions. Awareness of this clinical entity and of the high sensitivity of MR imaging for demonstrating edema caused by the fracture should prevent confusion with metastatic disease and inappropriate treatment.

Aged↗
PubMed1993

Clinical stage I carcinoma of the cervix. Value of MR imaging in determining invasion into the parametrium.

Using MR imaging with a body coil parametrial invasion was determined prospectively in 169 consecutive patients considered on the basis of clinical examination to have carcinoma confined to the cervix. After radical hysterectomy correlation with histologic examination was performed for the left and right parametrium separately. The criterion for parametrial invasion was a high-signal-intensity lesion with disruption of the full thickness of the cervical stroma combined with areas of abnormal signal intensity within the parametrial region on T2-weighted images. Histologic examination showed that 18 parametria in 13 patients were invaded by tumor. MR had an overall accuracy of 93%, a sensitivity of 89%, and a specificity of 93% in demonstrating parametrial involvement. Positive and negative predictive values were 43% and 99%. The main weakness of MR was 21 false-positive tests. This represents a limitation when MR is performed with a body coil.

Adult↗
PubMed1991

[Carotid endarterectomy. Surgical complications and long-term prognosis].

227 patients underwent 259 carotid endarterectomies because of transitory ischemic attacks (TIA). All had a 50% or more carotid lumen reduction as revealed by angiography, and symptoms from the arteriosclerotic lesion. Surgical mortality/morbidity at 30 days was 2.6%. 5.3 years after the operation (1 month-13 years) the probability of stroke was 4.9%, which corresponds to a postendarerectomy stroke rate of 1% per year. The procedure may be of value if the rate of surgical complication is very low, but the net effect still depends upon the occurrence of other vascular complications during the follow-up period. The incidence of vascular diseases in this series of seriously affected arteriosclerotics was higher than in a matched normal population, and mortality was much higher. At present a somewhat restrictive indication for surgery seems justified.

Adult↗
PubMed1990

A phase II study of 5-fluorouracil/cisplatinum in recurrent cervical cancer.

Thirty-seven patients with recurrent cervical carcinoma entered a phase II study of cisplatinum and 5-fluorouracil (5-FU). They were divided into patients with recurrent lesions outside previously irradiated area (group 1) and those with at least one recurrent lesion inside this volume (group 2). The treatment schedule consisted of 5-FU 1,000 mg/m2 i.v. days 1 to 5 and cisplatinum 100 mg/m2 i.v. day 1. Thirty-two patients were evaluable for response and toxicity. In group 1, 4 out of 19 patients had complete response with a median duration of 18 months, 9 out of 19 had partial response with a median duration of 10 months. Only 2 out of 13 patients in group 2 achieved partial response. All patients suffered from nausea and vomiting. The dose limiting factor was bone marrow suppression. The response rate in group 1 (68%) is impressive and higher than previously reported after other chemotherapy regimens. We found, however, the regimen too toxic for patients with central recurrences in previously irradiated areas, though some of these patients achieved substantial pain relief.

Adult↗
PubMed1989

[Is short-stay treatment profitable?].

It is often said that the reimbursement from public insurance is too small to make it profitable for hospitals to perform day surgery and outpatient surgery. It is essential to make it clear whether one is referring to transferring a patient from inpatient stay to an outpatient situation of treatment or a patient who would alternatively not have been treated in hospital. In the first case outpatient treatment will be profitable for the hospital even if there is no specific reimbursement. If suitable patients are not transferred to the outpatient department, this must be because the hospital does not find the reimbursement profitable enough to compensate for problems connected with the organizational change. The second case represents an increase in the hospital's capacity and, strictly speaking, is quite different from a comparison of inpatient stays and outpatient treatment. To illustrate the method used to calculate the costs and benefits to the society from day surgery or outpatient treatment, we present key results from an examination of a short-stay unit at the county hospital of Ostfold, in Fredrikstad. Although this was not a pure day surgical unit (60 per cent of the patients remained until the next day), the results shed light on the economic aspects of pure day surgery as well. The most important effect of this unit was an increase in treatment capacity and a reduction in the time the patients spent waiting for treatment. We show that the unit was certainly profitable if patients were on sick leave for at least one percent of the months spent waiting.

Ambulatory Surgical Procedures↗
PubMed1989

Consistency in synesthetic experience to vowels and consonants: five case studies.

The present study attempted to specify the actual degree of consistency in synesthetic experience in two synesthetes and three non-synesthetes. By comparing colour chip selections, and size and density ratings, to the same set of stimulus letters on separate occasions, it was found that the synesthetic subjects showed a high consistency in responding over a short (24 hours) as well as a long (one year) time span. In comparison, the non-synesthetic subjects demonstrated less consistent responding when retested after 24 hours. However, the differences between the two groups were smaller than expected. Consistency to vowels and consonants was compared, and it was found that consistency to consonants was comparable to, or even higher than, vowel consistency in all subjects.

Adult↗
PubMed1987

Single and repeated dose pharmacokinetics of thio-TEPA in patients treated for ovarian carcinoma.

Triethylenethiophosphoramide (thio-TEPA) pharmacokinetics were studied in 15 patients being treated for epithelial ovarian carcinoma. Unchanged thio-TEPA was assayed in serum and urine by means of a gas chromatographic procedure. No accumulation or alteration of the pharmacokinetics occurred during therapy, which was continued for up to 7 months with biweekly administrations of 20 mg, after two initial loading courses with 20 mg daily for 3 consecutive days 2 weeks apart. No significant difference in the pharmacokinetics between i.m. and i.v. administration was demonstrated. However, three patients showed a reduced absorption ability from the i.m. injection site to the systemic circulation and an apparent increase in the elimination half-life (3.86 +/- 0.97 h), which could be of clinical relevance. A first-order elimination process with a short elimination half-life (approximately 1.5 h) was demonstrated for thio-TEPA in all patients after i.v. administration. The apparent volume of distribution averaged 50 1. The renal clearance was below 1% of the total-body clearance, which averaged 412 ml/min. The urinary excretion of unchanged thio-TEPA was complete within 8 h after administration, with an average urinary recovery of 0.14% of the dose. Calculation of the area under the serum concentration vs time curve revealed wide variation between patients (range 517-1480 ng/h ml-1), indicating the need for drug monitoring during therapy.

Adenocarcinoma↗
PubMed1986

Postabortal insertion of IUD.

During 1983, 823 first trimester therapeutic abortions were performed at the University Hospital of Trondheim, Norway. Of these patients, 229 had an IUD inserted at the end of the operative procedure. The remaining 594 patients served as controls. Microbiological samples were taken from the cervix and the urethra. No prophylactic antibiotic treatment was given. Compared to the group of patients not selecting an IUD as contraception, there was no increase in readmission frequency due to immediate postabortal IUD insertion. There were no positive cultures for N. gonorrhoeae, and the relative number of positive chlamydia cultures was the same in both groups. In the IUD group we did not find any increase in complications such as bleeding, pain, perforations or infections. During the first year of observation, 3 pregnancies occurred in the IUD group, giving a Pearl index of 1.3 pregnancies per year. Continuation rate after one year was 72.8%. We recommend immediate postabortal insertion of an IUD after first trimester abortion as a practical and safe procedure.

Abortion, Therapeutic↗