[Improved diagnosis of early cerebral infarct by the combined use of diffusion and perfusion].

Purpose: To evaluate the feasibility and the diagnostic efficacy of multislice diffusion-weighted and perfusion imaging in addition to FLAIR-TSE, T2w-GraSE and MR-angiography in the diagnosis of acute stroke.

Methods: 18 patients with acute stroke were examined at 1.5 Tesla (Gyroscan ACS-NT, Philips Medical Systems) within 6 (n = 9) and 6-48 (n = 9) hours, respectively, and followed at regular intervals.

[TIPSS: technical and clinical results after 4 years].

Purpose: Retrospective analysis of the technical and clinical results after transjugular portosystemic stent shunt (TIPSS) procedure.

Method: Between 1992 and 1996 we tried to establish a TIPSS in 90 patients. The indications were: recurrent variceal haemorrhage (n = 74), refractory ascites (n = 12), hepatorenal syndrome (HRS) (n = 4).

Breast lesion localization: a freehand, interactive MR imaging-guided technique.

Purpose: To evaluate interactive magnetic resonance (MR) imaging-guided preoperative needle localization and hookwire placement in the noncompressed breast in patients in the prone position.

Materials And Methods: Nineteen MR imaging-guided breast lesion localization procedures were performed in 17 patients aged 38-70 years (mean age, 48 years) by using an open-platform breast coil in either a 1.5-T, closed-bore imager (n = 14) or a 0.

[31P-mr spectroscopy of peripheral skeletal musculature under load: demonstration of normal energy metabolites compared with metabolic muscle diseases].

Purpose: 31P-MR spectroscopy of skeletal muscle under exercise was used to obtain the range of normal variation and comparison was made for different neuromuscular diseases.

Methods: 41 examinations of 24 volunteers and 41 investigations in 35 patients were performed on 1.5 T MR systems (Gyroscan 515 und S15/ACSII, Philips).

[MRI in patients with cardiac pacemakers: in vitro and in vivo evaluation at 0.5 tesla].

Purpose: MRI is currently regarded as absolutely contraindicated in patients with implanted cardiac pacemakers. In this prospective study safety and feasibility of MRI in patients with new generation pacemakers (PM) was evaluated in vitro and in vivo.

Methods: 14 PM models in vitro and 18 patients with implanted new generation PM underwent a MRI exam at 0.

Diagnostic value of a superparamagnetic iron oxide in MR imaging of chronic liver disease in an animal model.

Objective: The enhancement characteristics and the diagnostic value of a cell-specific superparamagnetic contrast agent (NSR 0430) in different degrees of liver fibrosis and cirrhosis were experimentally studied in an animal model.

Materials And Methods: Chronic liver damage was induced in rats either by oral administration of carbon tetrachloride (CCl4) for 15 weeks (n = 37) or by oral administration of thioacetamide (TAA) in drinking water for 24-26 weeks (n = 48). Twenty-six animals served as control subjects.

[MR relaxation time measurements with and without selective fat suppression (SPIR) in endocrine orbitopathy].

Purpose: To determine the value and utility of relaxation time measurements with magnetic resonance (MR) imaging in patients with Graves' ophthalmopathy (G.O.).

Aspects of the Cryobiology of the Intertidal Harpacticoid Copepod Tigriopus brevicornis (O. F. Muller).

Cold-resistance studies of marine invertebrates have concentrated on intertidal sedentary organisms, which are often subjected to subzero air temperatures in winter. Mobile rock pool inhabitants have been rarely studied because such habitats are thought to buffer environmental variation. However, it is not uncommon for small upper-shore rock pools ( approximately 2 by 1 cm) to become completely frozen.

Effect of cytochrome P450 induction on phosphorus metabolites and proton relaxation times measured by in vivo 31P-magnetic resonance spectroscopy and 1H-magnetic resonance relaxometry in human liver.

Experimental and clinical studies have led to the hypothesis that the phosphodiester signal obtained by 31P magnetic resonance (MR) spectroscopy may be a specific marker for the hepatic induction of oxidative metabolism (P450 induction) by phenobarbitone or ethanol. Systematic studies in humans are lacking. Therefore, we studied 10 volunteers who received rifampin (600 mg/d) for 6 days, resulting in a documented induction of oxidative metabolism as measured by an increase in urinary 6-beta-hydroxycortisol output in all volunteers (P = .

Relationship between cytochrome P-450 induction by rifampicin, hepatic volume and portal blood flow in man.

Objective: Induction of hepatic cytochrome P-450-dependent oxidative metabolism is related to an almost identical increase (30%) in both the liver weight and portal blood flow in animals. In humans by contrast, an increased liver blood flow (44%) but no significant increase in liver volume has been reported.

Design: Therefore, we studied prospectively the relationship between P-450 induction by rifampicin, hepatic volume and portal blood flow in 10 healthy volunteers.

Consistent fat suppression with compensated spectral-spatial pulses.

Reliable fat suppression is especially important with fast imaging techniques such as echo-planar (EPI), spiral, and fast spin-echo (FSE) T2-weighted imaging. Spectral-spatial excitation has a number of advantages over spectrally selective presaturation techniques, including better resilience to B0 and B1 inhomogeneity. In this paper, a FSE sequence using a spectral-spatial excitation pulse for superior fat suppression is presented.

Comparative nutritional ecology of grass-feeding in a sub-Antarctic beetle: the impact of introduced species on Hydromedion sparsutum from South Georgia.

South Georgia has many introduced plant and animal species, a consequence of its long history of human habitation. Introduced reindeer have a strong effect on the vegetation of the Stromness Bay area by causing the replacement of indigenous species by grazing-tolerant grasses such as the exotic Poa annua, and in certain circumstances, the indigenous Festuca contracta. Recently it has been argued that an introduced predatory carabid has contributed to declines in the abundance and an increase in the body size of adults of the indigenous perimylopid beetle Hydromedion sparsutum.

RARE spiral T2-weighted imaging.

Spiral imaging has a number of advantages for fast imaging, including an efficient use of gradient hardware. However, inhomogeneity -induced blurring is proportional to the data acquisition duration. In this paper, we combine spiral data acquisition with a RARE echo train.

[Shortening of the measurement time by 1H-MR turbo spectroscopic imaging of the brain].

Purpose: Development of a new technique for reduction of measurement time in 1H-MR spectroscopic imaging of the brain. Optimisation of the sequence parameters in volunteer and in patient examinations and comparison to the results obtained with conventional 2 D-SI.

Methods: Examination of 20 healthy volunteers and 5 patients in a 1.

Differential scanning calorimetry studies on an Antarctic nematode (Panagrolaimus davidi) which survives intracellular freezing.

Differential scanning calorimetry was used to characterize thermal events associated with freezing and melting of suspensions and extracts of Panagrolaimus davidi, an Antarctic nematode which can survive intracellular freezing. Nematode suspensions produced a single freezing exotherm with a shoulder on the peak representing the freezing of the nematodes. A shoulder on the peak of melting endotherms indicates the melting of the nematodes and of the water surrounding them.

Temperature Regulation of Supercooling and Gut Nucleation in Relation to Diapause of Pyrrhocoris apterus (L.) (Heteroptera).

The heteropteran Pyrrhocoris apterus (L.) does not survive freezing of its body fluids; there is a good correlation between values of survival at subzero temperatures and the supercooling point (SCP), i.e.

A gE deleted infectious bovine rhinotracheitis marker vaccine for use in improved bovine herpesvirus 1 control programs.

Based on a glycoprotein E (gE) deleted bovine herpesvirus 1 (BHV1) strain (Kaashoek et al., 1994) a killed virus as well as a modified live virus marker vaccine have been developed that allow differentiation between immunized and BHV1 infected cattle. Safety and efficacy of both vaccines were tested extensively following the current European Union (EU) requirements for the development of bovine vaccines.

Determination of 1H relaxation times of water in human bone marrow by fat-suppressed turbo spin echo in comparison to MR spectroscopic methods.

Relaxation times of water were measured in human vertebral bodies by a fat-suppressed dual-echo turbo spin echo/turbo inversion recovery MRI sequence. Comparison was made with T1 and T2 values obtained by localized 1H-MR spectroscopy. The accuracy of the results and the diagnostic potential of the fast quantitative MRI technique were evaluated in 20 volunteers, 11 patients with osteoporosis, 6 patients with lymphoma, and 6 patients with bone marrow metastasis.

Enhancement efficacy of magnetic starch microshperes (MSM) in conventional spin-echo and turbo spin-echo sequences at 0.5 T and 1.5 T.

The efficacy of the superparamagnetic contrast agent magnetic starch microspheres (MSM) was evaluated in vitro by NMR relaxometry and in vivo by MR imaging using T2-weighted spin-echo (SE) and turbo spin-echo (TSE) sequences at 0.5 T and 1.5 T in 60 normal rats who received MSM in doses of 10-50 mu mol/kg.

[1H-MR spectroscopic imaging in patients with clinically diagnosed Alzheimer's disease].

Purpose: To detect regional differences in accompanying metabolic changes, 1H-Magnetic Resonance Spectroscopic Imaging (MRSI) was performed in 16 patients with Alzheimer's disease (AD); the clinical diagnosis was based upon DSM-III-R and NINCDS-ADRDA guidelines.

Methods: In the hippocampal region metabolic maps of the local distribution of N-acetylaspartate (NAA), choline (Cho), creatine compounds (P(Cr)) and lactate were determined. Ratios of Cho/NAA, (P)Cr/NAA and Cho/(P)Cr calculated from selected hippocampal spectra were compared to those from healthy volunteers (n = 17).

The invasion of the carnivorous carabid beetle Trechisibus antarcticus on South Georgia (sub-Antarctic) and its effect on the endemic herbivorous beetle Hydromedion spasutum.

Recently two species of carabid beetle were accidentally introduced onto the sub-Antarctic island of South Georgia. Both species are carnivorous and flightless. One of the species, Trechisibus antarcticus, is locally very abundant and in the process of invading the coastal lowland area, where the endemic herbivorous beetle Hydromedion sparsutum (Perimylopidae) is common.

Safety aspects in the development of an infectious bovine rhinotracheitis marker vaccine.

Clinical trials in cattle demonstrated that the IBR marker modified live vaccine based on the gE-deleted IBR strain Difivac is immunogenic and safe for bovines of all ages. Potential effects of the vaccine virus have also been tested in swine and sheep and proved safe for these species as well. For evaluation of other environmental aspects, the spread of the vaccine virus after immunisation was investigated.

Mitochondrial encephalomyopathy: correlation of P-31 exercise MR spectroscopy with clinical findings.

Purpose: To evaluate the sensitivity of standardized exercise phosphorus-31 magnetic resonance (MR) spectroscopy in screening for subclinical muscle involvement in mitochondrial encephalomyopathy and to estimate if changes seen at biopsy have functional consequences.

Materials And Methods: Exercise MR spectroscopy was performed in 52 examinations of 18 healthy volunteers and 14 patients with defects of mitochondrial respiratory chain enzymes. Calculation and kinetic analysis of the phosphocreatine (PCr) index and pH time courses were standardized with a microcomputer program.

Effects of temperature elevation on a field population of Acyrthosiphon svalbardicum (Hemiptera: Aphididae) on Spitsbergen.

A manipulation experiment was carried out on a field population of the aphid Acyrthosiphon svalbardicum near Ny Ålesund, on the high arctic island of Spitsbergen, using cloches to raise temperature. An average rise in temperature of 2.8 deg.