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At least 523 records · Page 29Linked to original sources
PubMed1978

Adrenoleukodystrophy. A correlative analysis of computed tomography and radionuclide studies.

A discrepancy in location of abnormality has been noted between computed tomography (CT) and radionuclide studies in patients with adrenoleukodystrophy (ALD). Radionuclide concentration occurs only in the periphery of the lesion or area of acute demyelinating process and no concentration is seen in the area af gliosis whereas gliosis appears as a low-density lesion in the CT scan. Forward migration of radionuclide uptake in the follow-up study is another characteristic feature of this disease.

Child↗
PubMed1979

Cross-correlation analysis of connectivities among cat lumbosacral dorsal horn cells.

1. Eighty-three cell pairs were recorded in dorsal horns of 19 cats. Cross-correlograms were flat in 65 cell pairs; of the remaining 18 pairs, cross-correlograms had broad peaks or troughs suggestive of nonmonosynaptic causal relations in their discharges; one cell pair had a biphasic deviation from base line. 2. No cross-correlograms indicative of monosynaptic interactions were observed. 3. All cell pairs with nonflat cross-correlograms had overlapping receptive fields. 4. It is concluded that monosynaptically connected cell pairs are rare at the interelectrode distances used in this experiment because such cell pairs must lie close together on the somatotopic map or because our recording methods bias against monosynaptically linked cell pairs.

Animals↗
PubMed1981

Accuracy of angiographic determination of left main coronary arterial narrowing. Angiographic--histologic correlative analysis in 28 patients.

To evaluate the accuracy of coronary angiography in identifying severe narrowing of the left main coronary artery (LMCA), the degree of narrowing observed by angiography was compared to that observed at necropsy in 28 patients with symptomatic coronary heart disease in whom angiography had been performed within 40 days of death. The angiograms were evaluated independently by three experienced angiographers. In 20 of the 28 patients (71%), the degree of narrowing of the LMCA was either underestimated (13 patients) or overestimated (10 patients) by two or three of three angiographers; of 84 angiographic judgments made by the three angiographers in the 28 patients, 54 (64%) were underestimates (33 judgments, 39%) or overestimates (21 judgments, 25%) of the degree of LMCA narrowing. Of 12 LMCAs narrowed 76-100% in cross-sectional area at necropsy, six were underestimated at preoperative angiography by two or three of three angiographers; of 12 LMCAs narrowed 51-75% in cross-sectional area at necropsy, all 12 were either under- or overestimated angiographically by two or three of three angiographers; of four LMCAs narrowed 26-50% in cross-section at necropsy, two were overestimated by two of three angiographers. Thus, angiographic determination of degrees of narrowing of the LMCA during life is subject to considerable error. The angiographic errors appear to have resulted primarily from the presence of atherosclerotic plaque in the LMCA and an insufficient number of angiographic projections.

Adult↗
PubMed1987

Gas chromatographic-light microscopic correlative analysis of excimer laser photoablation of cardiovascular tissues: evidence for a thermal mechanism.

The present series of experiments used gas chromatography to identify vapor-phase photoproducts liberated during excimer laser irradiation of cardiovascular tissues in air and blood. In air, laser beams produced from ArF (193 nm) and XeF (351 nm) excimer laser gas mixtures were delivered to samples of myocardium and atherosclerotic coronary arterial segments through the wall of a quartz cell, using 8-40 mJ/pulse. In blood, 351 nm were delivered via an optical fiber, using 14 mJ/pulse. When the experiments were performed using an air-tissue interface, the dominant photoproducts identified in order of elution from the gas chromatographic column were methane, acetylene, ethylene, ethane, propyne, allene, propylene, propane, and butene. When a fiberoptic was used to accomplish 351-nm excimer laser tissue ablation in a blood field, a similar gas chromatographic spectral distribution was observed. These vapor-phase photoproducts are indistinguishable from those observed following continuous wave laser irradiation or flame torching of cardiovascular tissues. Thus, despite the fact that excimer laser ablation of cardiovascular tissues is characterized by the absence of signs of thermal injury, the results of these experiments suggest that the predominant mechanism of excimer ablation is, like continuous-wave laser irradiation, a thermal process.

Biomechanical Phenomena↗
PubMed1996

Overnight growth hormone secretion in achondroplasia: deconvolution analysis, correlation with sleep state, and changes after treatment of obstructive sleep apnea.

The normal profile for overnight GH secretion in achondroplasia has not been previously studied. Factors that have been shown to influence GH secretion include age, obesity, sleep state, and the presence of obstructive sleep apnea (OSA). We assessed GH levels in a group of subjects with achondroplasia, during overnight polysomnography. Nineteen subjects with achondroplasia were studied at 11.3 y of age (median 6.7, range 1.8-30.9). Levels of GH were measured using time-resolved immunofluorometric assay (DELFIA, Pharmacia Biotech Inc.) and analyzed by a deconvolution method. Five subjects were restudied after treatment for OSA. Secretion rates of GH were greater in slow wave (SWS) and rapid eye movement (REM) sleep than in stage one and two (SI-II = light non-REM) sleep (p < 0.01). Total overnight GH secretion decreased with increasing age (r2 = 0.22 p < 0.04). Neither the frequency of arousals, frequency of sleep state transitions nor the severity of OSA correlated with measures of GH secretion. Levels of IGF-I correlated independently with age, body weight (percent ideal), and GH secretion rate (r2 = 0.76, p < 0.001). In a group of five subjects treated for OSA, improved respiratory distress index and reduced sleep state transitions were not associated with significant changes in GH secretion rate by sleep stage; SWS [from 0.62 +/- 0.28 mIU/L/min to 1.02 +/- 0.25 mIU/L/min (NS)] and SI-II sleep [from 0.26 +/- 0.07 mIU/L/min to 0.60 +/- 0.16 mIU/L/min (NS)]. However, in those five subjects, a GH secretion peak during the first 2 h of SWS was initially absent, appearing only after treatment of OSA (1.09 +/- 0.38 mIU/L/min) compared with (2.40 +/- 0.59 mIU/L/min (p = 0.01). A profile of overnight GH secretion is presented for subjects with achondroplasia.

Achondroplasia↗
PubMed1994

Aberrant reinnervation of facial musculature in a subhuman primate: a correlative analysis of eyelid kinematics, muscle synkinesis, and motoneuron localization.

A macaque monkey with a preexisting facial nerve injury showed a synkinesis of perioral muscles with blinking and thus provided a serendipitous model for a multiphasic analysis of this common neurologic syndrome. The amplitude of the paretic eyelid in spontaneous and air-puff-induced blinks was about one-third that of the normal eyelid. Despite the blink hypometria, induced blink durations remained matched for the two lids. EMG confirmed co-contraction of the zygomaticus and orbicularis oculi muscles on the affected side during blinking, with silence of the zygomaticus on the normal side. Neuroanatomic investigation showed that, on the affected side, some zygomaticus motoneurons were in the somatotopically correct nuclear subdivisions but that the majority were in the dorsal subdivision, which normally innervates the orbicularis oculi. This study supports the contention that some orbicularis oculi motoneurons are incorrectly rerouted to supply the perioral musculature following recovery from a peripheral seventh-nerve injury. This same pattern of relative weakness in eyelid muscles and the stereotyped co-contraction of lid and perioral muscles with blinking occurs in humans, suggesting that aberrant reinnervation may be the mechanism for this clinical phenomenon.

Animals↗
PubMed2005

Histogenetic phenotypes of B cells in posttransplant lymphoproliferative disorders by immunohistochemical analysis correlate with transplant type: solid organ vs hematopoietic stem cell transplantation.

We immunohistochemically defined the histogenesis of posttransplantation lymphoproliferative disorders (PTLDs; B-cell phenotype) occurring after allogeneic T cell-depleted hematopoietic stem cell transplantation (HSCT; n = 15) or solid organ transplantation (SOT; n = 11) to determine whether transplantation type or morphologic subtype of PTLD affected the histogenetic subtype. Immunohistochemical stains using histogenetic markers for germinal center (GC) B cells, late GC and post-GC B cells, and post-GC B cells were performed on paraffin-embedded samples. Morphologically, 14 cases were polymorphic; 12 were monomorphic. Histogenetic marker expression was as follows: 1 monomorphic case (4%), GC phenotype expressing bcl-6 and CD10; 17 cases (65%; polymorphic, 9; monomorphic, 8), late GC-early post-GC phenotype expressing MUM1/IRF4; 8 cases (31%; polymorphic, 5; monomorphic, 3), post-GC phenotype expressing MUM1/IRF4 and CD138 but not bcl-6. PTLD cases after HSCT more frequently were post-GC phenotype than after SOT (7/15 vs 1/11, respectively; P = .040) and were independent of morphologic subclassification. Results suggest that most PTLDs are late GC-early post-GC phenotype with a minor group of post-GC phenotype and rare cases of GC phenotype. Findings also suggest a correlation between histogenetic phenotype of B-cell PTLD and type of transplantation.

Adult↗
PubMed2006

[Correlation analysis of microsatellite DNA markers with wool traits in Liangshan semi-fine wool sheep].

Eighteen microsatellites on chromosomes 1, 2, 3, 9 were studied to detect their genotypes in 206 individuals in a Liangshan Semi-fine Wool Sheep nucleus breeding population. A GLM procedure was used to analyze the effects of these 18 microsatellites on wool traits. Results uncovered 7 loci that had a significant impact on wool traits. Genotypes of that favorably affect wool traits were determined.

Animals↗