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991.
OBJECTIVE: Our objective was to determine the ease of installation and use of relatively inexpensive and free software applications that allow Macintosh users to receive and view CT images from a Digital Imaging and COmmunication in Medicine-compliant imaging network. CONCLUSION: Simple-to-use Macintosh-based options to transfer and view images are readily available and easily installed by users with minimal computer expertise. 相似文献
992.
Unilateral 6-hydroxydopamine lesions of meso-striatal dopamine neurons and their physiological sequelae 总被引:1,自引:0,他引:1
One of the primary approaches in experimental brain research is to investigate the effects of specific destruction of its parts. Here, several neurotoxins are available which can be used to eliminate neurons of a certain neurochemical type or family. With respect to the study of dopamine neurons in the brain, especially within the basal ganglia, the neurotoxin 6-hydroxydopamine (6-OHDA) provides an important tool. The most common version of lesion induced with this toxin is the unilateral lesion placed in the area of mesencephalic dopamine somata or their ascending fibers, which leads to a lateralized loss of striatal dopamine. This approach has contributed to neuroscientific knowledge at the basic and clinical levels, since it has been used to clarify the neuroanatomy, neurochemistry, and electrophysiology of mesencephalic dopamine neurons and their relationships with the basal ganglia. Furthermore, unilateral 6-OHDA lesions have been used to investigate the role of these dopamine neurons with respect to behavior, and to examine the brain's capacity to recover from or compensate for specific neurochemical depletions. Finally, in clinically-oriented research, the lesion has been used to model aspects of Parkinson's disease, a human neurodegenerative disease which is neuronally characterized by a severe loss of the meso-striatal dopamine neurons. In the present review, which is the first of two, the lesion's effects on physiological parameters are being dealt with, including histological manifestations, effects on dopaminergic measures, other neurotransmitters (e.g. GABA, acetylcholine, glutamate), neuromodulators (e.g. neuropeptides, neurotrophins), electrophysiological activity, and measures of energy consumption. The findings are being discussed especially in relation to time after lesion and in relation to lesion severeness, that is, the differential role of total versus partial depletions of dopamine and the possible mechanisms of compensation. Finally, the advantages and possible drawbacks of such a lateralized lesion model are discussed. 相似文献
993.
DM Brown N Kania LA Lantieri EN Pasia RK Khouri 《Canadian Metallurgical Quarterly》1995,16(11):757-759
The concentration of phosphate in buffered saline irrigation solutions was evaluated for its effect upon the incidence of arterial thrombosis. A rabbit thrombosis model of combined intimal abrasion and twisted pedicle in the rabbit central ear artery was used. Higher concentrations of phosphate (20 mM) in normal saline yielded a lower thrombosis rate at 7 days postoperatively (50%) in comparison to 5 mM phosphate (89% thrombosis rate; P < 0.05). A standard phosphate-buffered salt solution (Dulbecco's; 9.5 mM phosphate with potassium, calcium, and magnesium salts) also had a high thrombosis rate (91%). This study demonstrates that subtle variations in the irrigation solution can have profound effects upon arterial thrombosis. 相似文献
994.
This article reviews the numerous applications of ultrasound in the musculoskeletal system. Emphasis is made on the important and often under-utilized role of ultrasound in infections, vascular lesions, arthritis, and trauma. 相似文献
995.
W Gilchrist E Burkhalter C Eaton RP Schaudies C Maydonovitch F Andrada AR Maged RK Wong 《Canadian Metallurgical Quarterly》1994,89(1):97-100
The first case of cutaneous lymphatic sporotrichosis from Nagaland and a case of cutaneous sporotrichosis from Kerala who had acquired infection from Assam are reported. The diagnosis in both cases were established by isolating Sporothrix schenckii from multiple cutaneous lesions. The dimorphic nature of fungus was established in vitro by demonstrating the mycelial phase at 25-30 degrees C and yeast phase at 37 degrees C and pathogenicity to white mice. Both the patients were successfully treated with oral administration of potassium iodide for 3 months. 相似文献
996.
997.
Our previous canine research suggested that the determination of peritoneal fluid lactic acid levels may be helpful in the evaluation of potential acute abdomen cases. To investigate the clinical significance of those findings, we obtained simultaneous peritoneal and plasma lactic acid values from patients undergoing emergency celiotomy or in whom surgical consultation was sought to rule out an acute abdomen. The lactic acid value was significantly higher in peritoneal fluid than in plasma in patients who were found to have hollow viscus perforation, gangrenous intestine, peritonitis, or intra-abdominal abscess. In contrast, the values were similar in patients who did not have those conditions. Our findings suggest that the calculated difference between simultaneous peritoneal and plasma lactic acid values is a helpful diagnostic index for patients in whom the diagnosis of acute abdomen is not otherwise obvious. 相似文献
998.
A series of substituted 1-acyl- and 1,2-diacyl-3,5-pyrazolidinediones were found to have hypolipidemic properties lowering both serum cholesterol and triglyceride levels in rodents. For optimal activity of the pyrazolidinediones, both nitrogen atoms of the ring needed to be substituted preferentially with MeCO groups. This compound lowered rat VLDL but did not elevate HDL cholesterol content. 相似文献
999.
Neutrophil adhesion to microvascular endothelium at sites of acute inflammation is regulated by both chemotactic peptides and lipid-derived mediators. Tumour necrosis factor-alpha (TNF-alpha) is a pro-inflammatory peptide that up-regulates endothelial expression of intercellular adhesion molecule-1 (ICAM-1) and endothelial leucocyte adhesion molecule-1 (E-selectin), while platelet-activating factor (PAF) is a potent lipid mediator that induces vascular changes via an unknown mechanism. Both have been shown to increase leucocyte-endothelial adhesion in various in vitro models of acute inflammation; however, the combined effects of recombinant TNF-alpha (rTNF-alpha) and PAF on neutrophil-endothelium adhesion have not been well described. In this study, we found rTNF-alpha at 0.5 ng/ml and PAF at 10 microM acted synergistically to increase neutrophil adherence to cultured umbilical vein endothelial cells 4 hr after stimulation. This increased neutrophil-endothelial adhesion was, in part, dependent on up-regulated expression of ICAM-1 and E-selectin since application of anti-ICAM1 and anti-E-selectin F(ab')2 fragments markedly diminished adhesion. Cultures stimulated with rTNF-alpha (0.5 ng/ml) or PAF (10 microM) alone did not show a significant increase in neutrophil adhesion, and neither ICAM-1 nor E-selectin expression was up-regulated as determined by flow cytometric analysis of endothelial cells. These results indicate that rTNF-alpha and PAF act synergistically to increase neutrophil-endothelial adhesion by stimulating endothelial expression of ICAM-1 and E-selectin and, thus, may play important roles in the onset and severity of acute inflammatory reactions. 相似文献
1000.