| 1. |
- Anderson, Leif G., et al.
(författare)
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The effect of the Siberian tundra on the environment of the shelf seas and the Arctic Ocean
- 1999
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Ingår i: Ambio. - 0044-7447. ; 28:3, s. 270-280
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Tidskriftsartikel (refereegranskat)abstract
- The Tundra Ecology -94 expedition investigated inflow of inorganic and organic carbon to the shelf seas by river runoff, and its transformation by biochemical processes in seawater and sediment. In addition, anthropogenic radionuclides, 137Cs, 90Sr, and 239,240Pu, were studied in water and sediments. The distribution of dissolved inorganic carbon indicates that the majority of the Ob and Yenisey discharges flow into the Laptev Sea before entering the central Arctic Ocean. The sediment study shows that there is a marked difference in benthic oxygen uptake, efflux of dissolved inorganic carbon and nutrients between localities. 137Cs activity from the Chernobyl accident is 30% in the Barents, Kara, and Laptev Seas. 137Cs increased from 5-8 Bq m-3 in Barents Sea, 5-13 Bq m-3 in the Kara Sea to 8-15 Bq m-3 in the Laptev Sea, but with locally low concentrations at the river mouths. Corresponding values for 90Sr were 2.5, 3, and 4 Bq m-3, respectively.
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| 2. |
- Engström, Per E., et al.
(författare)
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Effect of high voltage electrical pulses on subcutaneous glioma tumours on rats
- 1998
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Ingår i: Bioelectrochemistry and Bioenergetics. - 0302-4598. ; 47:1, s. 163-166
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Tidskriftsartikel (refereegranskat)abstract
- The antitumour effect of applied high voltage exponential pulses was investigated on rats with subcutaneously implanted N32 brain tumours. Superficial tumours on the thigh were produced by the injection of 100 000 N32 glioma cells on Fischer-344 rats. Four weeks after inoculation, a solid tumour has grown to a size of about 1 cm located directly under the skin. Short electric high voltage pulses were given transdermally through stainless steel plate electrodes. Sixteen exponential pulses with initial field strength of 1300-1400 V/cm and a time constant of 1 ms were delivered with a BTX600 device at approximately one pulse per second. The treatment was repeated during 4 consecutive days. Tumour response was studied by measuring the length, width and thickness of the tumour with a slide-calliper and estimating the tumour volume as an ellipsoid. Animals (treated and controls) were sacrificed when the size of the tumour had reached a predetermined value (5 cm3). In the first experiment this occurred after 50±4 days for the treated animals, excluding cured, compared to 40±1.3 for their controls and in the second experiment after 64±24 days excluding cured animals compared to 37.6±3 for the controls. All treated animals showed an initial partial or complete tumour remission within a few days after the end of the 4-day treatment. Two out of ten treated animals were cured with no sign of recurrence after 100 days. Copyright (C) 1998 Elsevier Science S.A.
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| 3. |
- Friberg, Britt, et al.
(författare)
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Endometrial destruction by thermal coagulation : Evaluation of a new form of treatment for menorrhagia
- 1998
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Ingår i: Gynaecological Endoscopy. - : Wiley. - 0962-1091 .- 1365-2508. ; 7:2, s. 73-78
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Tidskriftsartikel (refereegranskat)abstract
- Objective. To report the first clinical evaluation of a new balloon endometrial, thermal destruction system Cavaterm®, for outpatient treatment of menorrhagia. Design. To elucidate possible technical problems during treatment, to evaluate how the patients tolerated the treatment and to judge which patients were suitable for this form of treatment. Main outcome measures. Measurements of bleeding volumes in pads and tampons before and after treatment were performed as well as subjective evaluation by bleeding charts. Patients also estimated their degree of satisfaction. Setting. Gynaecology department at a university hospital. Subjects. 36 patients under 52 pears of age with menorrhagia, without suspicion of intracavitary pathology including malignancy. Results. No procedure-related complications occurred. The patients tolerated the treatment well. There was a significant reduction in measured bleeding volumes in pads and tampons, collected during one menstruation, 2-7 months after treatment compared with measurements before treatment. Four patients subsequently underwent hysterectomy and should not have been included in the study (two with pedunculated myoma and one with a septum; the fourth showed premalignant endometrial changes in the curettage preceding the treatment). At 18-28-month follow up, 29 of the suitable patients (91%) reported a significant reduction in bleeding and another three patients reported reduced but still profuse bleeding compared with pretreatment; 88% (28/32) rated the treatment results as excellent, and a further 9% (3/32) as good. Conclusions. We found the Cavaterm® system for endometrial destruction to be safe, efficient and easy to use.
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| 4. |
- Möller, Páll H., et al.
(författare)
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Interstitial laser thermotherapy : Comparison between bare fibre and sapphire probe
- 1995
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Ingår i: Lasers in Medical Science. - 0268-8921. ; 10:3, s. 193-200
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Tidskriftsartikel (refereegranskat)abstract
- A sapphire probe and a bare fibre were compared with respect to temperature control and distribution and light fluence in interstitial laser thermotherapy. Experiments were performed in processed liver using an Nd-YAG laser and output power levels of 1-4 W. The temperature was controlled at a distance of 10 mm using a feedback circuit with an automatic thermometry system and thermistor probes. With the sapphire probe, carbonization was rare at power levels of 1-2 W but was observed in half of the experiments at 3 W and in all experiments at 4 W. Using the bare fibre, carbonization was seen in almost all experiments. Absence of carbonization was associated with a moderate decrease in the penetration of light and excellent control of the temperature, whereas carbonization led to rapid impairment of light penetration and temperature control. In addition, the temperature gradient was smaller with the sapphire probe than with the bare fibre or when carbonization was absent. It is concluded that a diffuser tip, such as the sapphire probe, may be preferable to the bare fibre for interstitial laser thermotherapy because it gives a smaller temperature gradient and helps to avoid carbonization which results in preserved light penetration and improved temperature control.
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| 5. |
- Persson, Bertil R.R., et al.
(författare)
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Numerical calculations of temperature distribution resulting from intracavitary heating of the uterus
- 1998
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Ingår i: Gynaecological Endoscopy. - 0962-1091. ; 7:4, s. 203-209
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Tidskriftsartikel (refereegranskat)abstract
- Objective To estimate, using numerical calculations, the depth of tissue damage in the uterus following balloon thermal endometrial destruction. Design A parameter, therapeutic depth, was defined. This was the maximum depth into the uterine myometrium, from the uterine cavity, at which a predefined temperature was reached after a certain time and with a constant intracavitary temperature. Setting Departments of radiation physics and gynaecology at a university hospital. Results After 30 min of treatment with an intracavitary temperature of 75°C, the maximum depth into the myometrium at which the tissue had been exposed to a temperature of 55°C, when blood flow was neglected, was 8.9 mm. Taking into account blood flow the depth was 3.4 mm, and including the pressure because of the balloon it was 5.6 mm. With the inclusion of a local increase in blood flow because of elevated tissue temperature the depth was 4.4mm. Finally when damage to blood vessels due to coagulation was also accounted for, the depth was 5.2mm. The therapeutic depth decreased only slightly when the treatment time was shortened to 15 min. Conclusions Numerical calculations provide a basis for estimation of the optimal intracavitary temperature and treatment time when performing thermal endometrial destruction by means of a balloon catheter.
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