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21.
We used a quantitative immunoassay to examine the effects of human serum and immunoglobulins on neurofilament protein expression in cultures of chick spinal neurons. Compared with cultures grown in the presence of serum from healthy controls or patients with other neurologic disorders, ALS serum lowered the level of neurofilament proteins. Effects were similar with or without muscle-derived neurotrophic factors; there was no specificity for motor neurons. No neurotoxic activity was found in immunoglobulin fractions, and there was no evidence of circulating antibodies that might neutralize muscle-derived neurotrophic factors or induce cytolysis of spinal neurons. 相似文献
22.
BACKGROUND: Production of grammatical morphology is typically impaired in agrammatic aphasic individuals, as is their capacity to produce the syntactic structure responsible for licensing that morphology. Whether these two impairments are causally related has been an issue of long-standing debate. If morphological deficits are a side-effect of underlying syntactic ones, as has been claimed (Friedmann & Grodzinsky, 1997; Izvorski & Ullman, 1999), therapy which improves the syntactic deficit should remediate the morphological deficit as well. This paper reports a case study of one individual with such co-occurring impairments and describes their recovery in response to linguistically-motivated treatment targeting his syntactic deficits. METHODS #ENTITYSTARTX00026; PROCEDURES: MD is a 56 year-old male diagnosed with non-fluent Broca's aphasia subsequent to a left-hemisphere CVA, with limited capacity to produce syntactically complex utterances and grammatical morphology. He was enrolled in therapy using Treatment of Underlying Forms (TUF; Thompson & Shapiro, 2005), targeting production of sentences involving Wh-movement (object relative clauses). MD participated in twice-weekly treatment sessions for approximately two months, with daily probes assessing his production of treated and untreated sentence types. In addition, probes assessing his grammatical morphology and sentence production were administered pre- and post-treatment. OUTCOMES #ENTITYSTARTX00026; RESULTS: Pre-treatment scores in tests of grammatical morphology and sentence production indicated deficits in both domains. During treatment, MD successfully acquired production of a variety of sentence with Wh-movement, though this did not generalize to sentences involving a grammatically distinct movement operation (NP-movement). Post-treatment scores also indicated a lack of improvement in production of grammatical morphology. CONCLUSIONS: The dissociation between MD's morphological and syntactic recovery indicates that the recovery of syntactic and morphological processes in aphasia may occur independently. This result is thus surprising under approaches in which morphological and syntactic impairments are strongly and causally related in aphasia, such as the Tree-Pruning Hypothesis (Friedmann, 2001; Friedmann & Grodzinsky, 1997). Further, these results reinforce the conclusion that aphasia treatment can lead to generalization, but only to linguistic material which is in a subset relation to trained structures (Thompson, Shapiro, Kiran & Sobecks, 2003). 相似文献
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25.
Epiploic appendagitis and omental infarction are benign self-limiting conditions that are more frequent than generally assumed.
Both disorders frequently mimic symptoms of an abdominal surgical emergency, often leading to clinical misdiagnosis of appendicitis
or diverticulitis. Because a misdiagnosis can result in an unnecessary laparotomy, a correct diagnosis is of great importance.
Ultrasound and computed tomography can be used to make a reliable diagnosis. This pictorial essay illustrates the various
ultrasonographic and computed tomographic appearances of epiploic appendagitis and omental infarction and focuses on their
radiologic differential diagnoses and pitfalls.
Received: 22 February 2001/Accepted: 18 April 2001 相似文献
26.
Selma C. Tromp Geert Jan Tangelder Dick W. Slaaf Robert S. Reneman S. van Velzen Wim Engels E. van Breda M. G. A. oude Egbrink 《Pflügers Archiv : European journal of physiology》1998,436(2):255-261
The objective of the present study was to determine the role of mast cells and histamine in leukocyte-endothelium interactions
in mesenteric venules of four rat strains: Brown Norway, Lewis, Sprague-Dawley and Wistar. Intravital microscopy showed that
the mast cell stabilizer cromoglycate (5 mg/kg i.v. just before exteriorization of the mesentery) did not affect the baseline
level and velocity of leukocyte rolling in any of the four strains. This finding is in agreement with the observation that
cromoglycate pretreatment only slightly influenced mast cell degranulation in all strains except the Brown Norway. After mast
cell stabilization, only in Sprague-Dawley did topical administration of histamine (10–4 M) result in a significant increase in the level of leukocyte rolling and a decrease in the rolling velocity compared with
the time control. Histamine induced leukocyte adhesion only in the Brown Norway strain. In conclusion, the hypothesis presented
in other studies, that degranulation of mast cells, and more specifically the release of histamine, is of major importance
for the induction of leukocyte-endothelium interactions in rat mesenteric venules is not generally applicable; the present
study shows a clear strain dependency.
Received: 18 July 1997 / Received after revision: 17 November 1997 / Accepted: 13 March 1998 相似文献
27.
28.
Characterisation of black-pigmented anaerobes isolated from diseased and healthy periodontal sites 总被引:4,自引:0,他引:4
Prevotella intermedia has recently been re-defined and a new species, Prevotella nigrescens has been proposed. However, there is little data available on the incidence of these new species in periodontal health or disease. Black-pigmented anaerobes isolated from diseased and healthy subgingival sites were identified by serotyping, SDS-PAGE and physiological tests. In adult periodontitis subjects, 64% of active sites, 35.7% of inactive sites and 38.5% of healthy sites yielded black-pigmented anaerobes. Of these, Porphyromonas gingivalis was found in 11% of active and 5% of healthy sites in diseased patients, Prevotella intermedia in 15.5% of active and 20.5% of healthy sites, Prevotella nigrescens in 37.7% of active and 11.5% of healthy sites and Prevotella denticola in 3% of active and 1% of healthy sites. In healthy subjects, 50% of sites yielded black-pigmented anaerobes. P. gingivalis was not found in healthy subjects but P. intermedia was found in 18% and P. nigrescens in 31% of sites. SDS-PAGE proved to be a useful method for routinely differentiating P. intermedia and P. nigrescens and two sub-types of the latter species were detected on the basis of band pattern. Only one P. nigrescens sub-type was found in any given individual and one type, typified by ATCC 25261, was more commonly found in deep pockets. However, overall both P. nigrescens and P. intermedia as species were just as frequently found at healthy sites as diseased sites. Thus, these species, in contrast to P. gingivalis , appear to be common commensals but they may act as opportunistic pathogens. 相似文献
29.
30.
Daniel W. Walsh Vincent B. Ho Michael F. Haggerty 《Journal of magnetic resonance imaging : JMRI》1997,7(2):312-315
Mycotic aneurysms of the abdominal aorta are potentially fatal but uncommon. We report the MRI and MRA features of an abdominal aortic mycotic aneurysm in a patient who presented with nonspecific low back pain. By delineating the saccular nature of the aneurysm and identifying the coexistence of vertebral enhancement, MRI was crucial for the final diagnosis. A potential pitfall of contrast-enhanced MRA is also demonstrated. 相似文献