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111.
RJ O''Hara J Greenman PJ Drew AW McDonald GS Duthie PW Lee JR Monson 《Canadian Metallurgical Quarterly》1998,41(4):460-463
OBJECTIVE: Spontaneous spinal epidural hematoma (SSEH) is an idiopathic accumulation of blood in the vertebral epidural space without identifiable predisposing factors. First reported in 1869, the clinical outcome in children younger than 18 years old has not been clearly delineated. DESIGN: A comprehensive review of the English language literature revealed 26 patients younger than 18 years old with reported clinical outcomes. The 27th case is presented. RESULTS: Complete neurologic recovery occurred in 14 of 27 (52%) patients, partial recovery in 12 of 27 (44%) patients, and death in 1 of 27 (4%) patients. CONCLUSION: There is an overall good prognosis for neurologic recovery in children who experience SSEH. 相似文献
112.
PJ Mulrow 《Canadian Metallurgical Quarterly》1998,30(6-7):346-349
Extrarenal renin has been found in a number of tissues. All the components of the renin-angiotensin system have been identified in the adrenal cortex. Adrenal renin has been found in many animal species, including the human, but most of the studies have been carried out in the rat. Renin is present and synthesized mainly in the zona glomerulosa cells. Renin production is under physiological control and can be influenced by ACTH, changes in electrolyte balance and the genetic background of the rat. The evidence suggests that adrenal renin plays a role as a local hormone in regulating aldosterone production by the zona glomerulosa cells. 相似文献
113.
The nucleus accumbens and ventral pallidum receive dopamine (DA) projections from the mesencephalon. Although DA inputs to the nucleus accumbens are implicated in both locomotion and reward processes, little is known of the behavioural significance of DA in the ventral pallidum. These studies examined the effects of D-amphetamine injected into the nucleus accumbens or ventral pallidum on locomotor activity and responding for a conditioned reward (CR). In the nucleus accumbens D-amphetamine dose dependently (1, 3 and 10 microg) increased locomotion within 5-10 min of injection. Intra-ventral pallidum microinjections of D-amphetamine also increased activity in this dose range, but the effect occurred with a longer latency (5-20 min). The magnitude of the response evoked by ventral pallidum injections was lower than that evoked by nucleus accumbens injections. The GABAA antagonist picrotoxin (0.1 microg) stimulated activity when injected into the ventral pallidum but not the nucleus accumbens, providing a pharmacological dissociation between the two injection sites. In the CR studies, D-amphetamine injected into both sites potentiated responding for a CR previously paired with food delivery, without altering responding on an inactive lever. Picrotoxin injected into the ventral pallidum reduced responding and abolished the selectivity of responding for CR. The results show that DA release in the ventral pallidum enhances locomotion and responding for a CR, providing evidence that DA in the ventral pallidum plays a significant role in the mediation of the effects of D-amphetamine. The failure of picrotoxin to elevate responding for CR despite increasing locomotor activity indicates that pharmacologically-induced blockade of GABAA receptors in the ventral pallidum disrupts goal-directed responding. 相似文献
114.
MH Mullerworth P Angelopoulos MA Couyant AM Horton SM Robinson OU Petring PJ Mitchell JJ Presneill 《Canadian Metallurgical Quarterly》1998,66(4):1242-1245
The use of PCR to amplify a specific virA gene fragment serves as a highly specific and sensitive method to detect virulent bacteria of the genus Shigella and enteroinvasive Escherichia coli. Amplification of a 215-bp DNA band was obtained by using isolated genomic DNA of Shigella, individual cells of Shigella dysenteriae, and mayonnaise contaminated with S. dysenteriae. Moreover, a multiplex PCR with specific (virA) and bacterium-restricted (16S ribosomal DNA) primers generated an amplification product of approximately 755 bp for all bacteria tested and an additional 215-bp product for Shigella and enteroinvasive E. coli. 相似文献
115.
PJ Johnson SC Tyagi LC Katwa VK Ganjam LA Moore JM Kreeger NT Messer 《Canadian Metallurgical Quarterly》1998,142(15):392-396
Samples of connective tissue obtained from the hoof of six laminitic and eight non-laminitic adult horses were analysed zymographically to investigate whether connective tissue matrix metalloproteinases are activated or induced during laminitis. The activity or matrix metalloproteinases was substantially greater in the tissues from the laminitic horses than in the tissues from the non-laminitic horses. A comparison of the collagenolytic activity in the laminitic and control tissues showed that collagenolytic activities corresponding to the 92 kDa (P < 0.001), 72 kDa (P < 0.01) and 66 kDa (P < 0.01) bands were induced in the laminitic tissues. 相似文献
116.
MJ O'Neill JA Lewis HM Noble S Holland C Mansat JE Farthing G Foster D Noble SJ Lane PJ Sidebottom SM Lynn MV Hayes CJ Dix 《Canadian Metallurgical Quarterly》1998,61(11):1328-1331
Methanolic extracts prepared from the leaves of Lantana camara have been found to inhibit human thrombin. An assay, in which thrombin activity is measured as a function of clot formation from fibrinogen, was used to guide the fractionation and purification of five principal active constituents (1-5), which were all characterized as 5,5-trans-fused cyclic lactone-containing euphane triterpenes. 相似文献
117.
TE Cawston VA Curry CA Summers IM Clark GP Riley PF Life JR Spaull MB Goldring PJ Koshy AD Rowan WD Shingleton 《Canadian Metallurgical Quarterly》1998,41(10):1760-1771
OBJECTIVE: To study the interaction of interleukin-1alpha (IL-1alpha) and oncostatin M (OSM) in promoting cartilage collagen destruction. METHODS: Bovine, porcine, and human cartilage and human chondrocytes were studied in culture. The levels of collagenase (matrix metalloproteinase 1 [MMP-1]) and tissue inhibitor of metalloproteinases 1 (TIMP-1) were measured by bioassay and enzyme-linked immunosorbent assay (ELISA). The levels of OSM in rheumatoid synovial fluid were measured by ELISA. RESULTS: When combined with OSM, IL-1alpha, IL-1beta, and tumor necrosis factor alpha released proteoglycan and collagen from cartilage. OSM was the only member of the IL-6 family to have this effect. Human tendon also responded to IL-1alpha and OSM. OSM increased the production of MMP-1 and TIMP-1 but when combined with IL-1alpha, synergistically promoted MMP-1 production in human chondrocytes and synovial fibroblasts. High levels of OSM were found in human rheumatoid synovial fluids, and confocal microscopy showed that OSM was produced by macrophages in rheumatoid synovial tissue. CONCLUSION: These results highlight an important new mechanism by which there is irreversible loss of collagen from cartilage. 相似文献
118.
J Vion-Dury AM Salvan S Confort-Gouny PJ Cozzone 《Canadian Metallurgical Quarterly》1998,27(27):1398-1405
NONINVASIVE EXPLORATION: Proton localized magnetic resonance spectroscopy (MRS) is a noninvasive human neurochemistry method based on the magnetic resonance phenomenon. ADVANTAGES: This exploration of brain metabolism, performed without any injection, detects neuronal, glial, and membrane markers, and can be performed after an MRI examination without moving the patient. INDICATIONS: In vivo brain MRS plays a major role (i) in early diagnosis of HIV-related encephalopathy, (ii) in differential diagnosis of HIV-related encephalopathy versus psychiatric symptoms or occurring in AIDS patients, (iii) in differential diagnosis of HIV-related encephalopathy versus other brain lesions related to AIDS, and (iv) in the follow-up of patient response to therapy. In these indications, MRS is frequently more reliable than neuropsychologic testing and more sensitive than MRI. 相似文献
119.
CR Dudley B Keavney IM Stratton RC Turner PJ Ratcliffe 《Canadian Metallurgical Quarterly》1995,48(6):1907-1911
We performed a case-control study to determine whether molecular variants of genes of the renin-angiotensin system were associated with the presence of albuminuria in non-insulin dependent diabetes mellitus (NIDDM). A total of 180 diabetic patients with persistent microalbuminuria [median urinary albumin (interquartile range) of 74 (54 to 126 mg/liter)] were matched with two control groups of diabetic patients without microalbuminuria [median urinary albumin 7 (5 to 10) mg/liter] for variables known to be associated with raised urinary albumin concentration including hemoglobin A1c and triglyceride. One control group was also matched for blood pressure and the other group was not, to allow assessment of interactions with hypertension. Association with the I/D polymorphism of the ACE gene and M235T variant of the angiotensinogen gene (AGT) with microalbuminuria and retinopathy was examined. There were no significant differences in genotype frequency between cases and controls for ACE or AGT irrespective of blood pressure matching. However, among subjects with microalbuminuria, those with the ACE DD genotype had a significantly greater urinary albumin excretion than individuals with a non-DD genotype [median 88 (68 to 170) mg/liter vs. 67 (53 to 113) mg/liter, P < 0.001]. More subjects with the DD than non-DD genotype had persistent albuminuria > 100 mg/liter, twice the upper normal range (60% vs. 38%, P = 0.006). When increased albumin excretion occurs, the presence of the ACE DD genotype appears to be associated with higher urinary albumin levels. No association with retinopathy was observed. 相似文献
120.
Capillary morphogenesis involves cell-cell and cell-matrix interactions. Proteases elaborated by capillary cells modify the extracellular matrix (ECM) to facilitate capillary tube formation. Previously, we detected the presence of fibronectin fragments (Fn-f) associated with the proform of matrix metalloprotease-2 (MMP-2) in conditioned medium of human retinal endothelial cells (HRECs). Association of this fragment to latent MMP-2 prevented autocatalytic activation of MMP-2, suggesting a modulatory role of Fn-f in MMP-2 activation. In this report, we examined the potential role of Fn-f on two processes involved in angiogenesis, proliferation and migration of vascular cells. The effects of Fn-f on proliferation were determined by DNA synthesis and cell counts. Their effects on migration were assessed using modified Boyden chambers. Seven Fn-f were tested on vascular cell migration and/or proliferation. Three Fn-f induced migration. Fn-f of 30-kDa and 120-kDa size positively affected proliferation of microvascular cells but not macrovascular cells. A 45-kDa gelatin binding fragment of Fn inhibited HREC proliferation but stimulated pericyte and smooth muscle cell proliferation. The potency of these fragments exceeded that of the known angiogenic growth factor, basic fibroblast growth factor (bFGF), on HREC migration. ECM components such as fibronectin may influence capillary morphogenesis by the generation of fragments that can modulate proliferation, migration, and protease activation. In the setting of diabetes, excess Fn is generated and is available for degradation. Thus, the production of Fn-f may be specifically relevant to the angiogenesis observed in proliferative diabetic retinopathy. 相似文献