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101.
We describe a new method for the percutaneous drainage of pancreatic pseudocysts using a transgastric approach. We used this technique in three dogs and six patients for whom no other "safe" access route was available. The procedures were performed under US guidance alone or with US combined with fluoroscopy. No complications were observed. 相似文献
102.
T. S. Olsen 《Acta neurologica Scandinavica》1986,73(4):321-337
Occlusions of the middle cerebral artery (MCA) are mostly of embolic origin (appr. 80%) and give rise to about one third of all ischemic strokes, most of these being major strokes. MCA occlusions lasting for less than 1/2 h are tolerated without occurrence of permanent tissue damage. Occlusions lasting between 1/2 h to 4-8 h lead to permanent tissue damage and neurological deficits that are proportional to the duration of occlusion. Maximal tissue damage is obtained after 4-8 h occlusion. A cerebral blood flow of 8-23 ml/100 gr/min is sufficient for cellular viability but insufficient for normal tissue function ("ischemic penumbra"). Cellular function is completely abolished in the interval 8-16 ml/100 gr/min and flow at that level is tolerated only for 1-3 h before neuronal death ensues. In the interval 18-23 ml/100 gr/min there is some functional activity although it is reduced. Experimental and clinical evidence suggests that flow in this interval may be tolerated for several days, months or even longer ("chronic ischemic penumbra"). After MCA occlusion the blood flow falls below 8 ml/100 gr/min in most cases and permanent MCA occlusion always leads to relatively large areas of frank infarction. The ischemic infarcts may be surrounded by collaterally perfused areas where the blood flow is pressure-dependent (impaired autoregulation) and quite commonly insufficient for normal neuronal function (below 23 ml/100 gr/min). Such collaterally perfused areas may include a "chronic ischemic penumbra". Emboli causing MCA occlusions commonly disintegrate and/or migrate more peripherally within the first few weeks post stroke. This leads to reperfusion and changes of ischemic infarcts into hyperemic infarcts where flow is severely increased. The vascular reactivity is completely abolished in hyperemic infarcts and the hyperemic state lasts for about two weeks. Probably, anemic infarcts are equivalent to ischemic infarcts while the hemorrhagic variety is equivalent to hyperemic infarcts. The "partial infarct" with selective neuronal necrosis occurs in experimental animals after MCA occlusions of less than four h but not after permanent MCA occlusion. The significance of partial infarction in human stroke is not clarified. The extent of irreversible tissue damage can be reduced only if therapy sets in within 4-8 h after the occlusion. If a "chronic penumbra" exists the extension of reversible tissue damage can be reduced if therapy aimed at increasing the blood flow in the penumbra sets in within weeks or even months after the stroke.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
103.
Rao VM; Dalinka MK; Mitchell DG; Spritzer CE; Kaplan F; August CS; Axel L; Kressel HY 《Radiology》1986,161(1):217-220
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements. 相似文献
104.
The effect of prolonged administration of the potent and specific 5-HT uptake inhibitor citalopram on behavioural measures of dopaminergic and serotonergic activity has been studied in rats. Administration of citalopram in the diet at a daily dose of 99 mol/kg led to supersensitivity to d-amphetamine-induced hypermotility and stereotypy and to subsensitivity to apomorphine-induced hypomotility 2 h after withdrawal. Forepaw clonus induced by 5-methoxy-N,N-dimethyltryptamine was decreased 2 h and 24 h after withdrawal and the number of head shakes induced by 1-5-HTP and citalopram were decreased 24 h after withdrawal. The d-amphetamine potentiation was still seen after 24 h, whereas the response had returned to normal 3 and 7 days after withdrawal. The content of amphetamine in three different brain regions was about 50% higher compared with controls 24 h after withdrawal of prolonged citalopram administration. At this time citalopram had been eliminated, and citalopram itself could not affect amphetamine metabolism. Other experiments indicated a linear relation between d-amphetamine brain concentration and motility level. Thus, a 50% increase in citalopram-treated rats cannot alone account for 3-fold increase in d-amphetamine-induced motility. Potentiation of d-amphetamine-induced hypermotility was also found after citalopram in a daily dietary dose of 25 mol/kg for 13 days and after oral bolus injection (49 mol/kg twice daily for 14 days). Acute citalopram injection had no effect in any of these models. The results suggest increased responsiveness of dopaminergic mechanisms mediating hypermotility, and decreased sensitivity of dopamine receptors mediating sedation (proposed autoreceptors). Sensitivity of 5-HT receptors was also decreased. The mechanisms by which citalopram induces d-amphetamine supersensitivity as well as subsensitivity to apomorphine and 5-HT agonists are presently unknown, since no changes in dopaminergic and serotonergic receptor binding have been found after an identical dose regimen. 相似文献
105.
Quality of Life Research - This study aims to provide new knowledge on the relative importance of key life domains amongst older adults, and how the Coronavirus pandemic has influenced their life... 相似文献
106.
IntroductionPatients with traumatic brain injury are referred to the neurosurgical unit at James Cook University Hospital, Middlesbrough, either from local accident and emergency departments (direct transfer from the scene) or from other hospitals (indirect transfer). This study looked at the outcome in both groups.Material and methodsThis was a retrospective observational study using trauma audit research network data for patients treated for traumatic brain injury at the neurosurgery department at the neurosurgical unit at James Cook University Hospital.ResultsA total of 356 patients with traumatic brain injury were admitted under the care of neurosurgeons; 143 (40%) of these patients had a neurosurgical procedure. Of the patients undergoing a neurological procedure, 111 patients were transferred directly while 32 were indirect transfers; 213 patients were managed conservatively. Of those managed conservatively, 165 were transferred directly while 48 were indirect transfers.We compared the length of hospital stay and Glasgow Outcome Scale score for the patients based on whether they were conservatively managed or required surgery in the direct and indirect transfer groups. The difference in the length of stay in the surgical and conservative groups following direct and indirect transfer was insignificant (p = 0.07). The time to the operation in direct and indirect transfer was also not statistically significant (p = 0.06).ConclusionPatients are as safe, if not safer, by reaching the nearest trauma unit with facilities for resuscitation and imaging. 相似文献
107.
Characterization of Salmonella enterica serovar gallinarum biovars gallinarum and pullorum by plasmid profiling and biochemical analysis 总被引:4,自引:0,他引:4
One-hundred-and-five strains of Salmonella enterica serovar gallinarum, biovar pullorum and 43 strains of biovar gallinarum were characterized by biochemical reactions, and 95 strains of biovar pullorum and 32 strains of biovar gallinarum were examined for plasmid content. Twenty-one (66%) of the strains classified as biovar gallinarum contained a 85-kb virulence plasmid. Six of these strains also contained a 2.5-kb plasmid. Ten strains (31%) were without plasmids. Ninety-three strains (98%) belonging to biovar pullorum contained the virulence plasmid and, in addition, these strains contained from one to four small plasmids. Two strains did not contain plasmids. Restriction enzyme digestions of the virulence plasmid showed three different profiles, two of which were common for biovars gallinarum and pullorum. It is suggested that the phenotypic diversity of biovars gallinarum and pullorum, as well as the diversity of plasmid profiles of biovar pullorum, could be used as epidemiological markers. Differences in phenotypic characters were not related to plasmids demonstrated in biovars of S. enterica serovar gallinarum. 相似文献
108.
Olsen JA 《Journal of health economics》1993,12(2):187-191
109.
Olsen RV 《Health facilities management》1990,3(2):28, 30-21, 33
110.