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1.
Patrick E. Barta Richard E. Powers Elizabeth H. Aylward Gary A. Chase Gordon J. Harris Peter V. Rabins Larry E. Tune Godfrey D. Pearlson 《Psychiatry Research: Neuroimaging》1997,68(2-3):65-75
Volumes of medial and lateral temporal lobe structures were assessed using magnetic resonance imaging (MRI) in 11 patients with late-life onset schizophrenia (LOS), 18 normal elderly controls and 12 patients with moderate cognitive impairment due to Alzheimer's disease (AD) who had no non-cognitive symptoms. While both patient groups has smaller volumes of several medial temporal regions (e.g. entorhinal cortex, left hippocampus), schizophrenics had significantly smaller anterior superior temporal gyri (STG) than normal controls, but AD patients did not. We have previously demonstrated anterior STG volume to be reduced in early life onset schizophrenia. 相似文献
2.
Syrian hamster sera may be assayed for hemolytic complement (C) activity by standard procedures with sensitized sheep erythrocytes as used for human sera, but mongolian gerbil sera had higher complement titers when tested with sensitized guinea pig erythrocytes as target cells. The optimal conditions for in vitro testing of hamster C were pH 7.3, ionic strength 0.15, and presence of 1 micrometer of Mg2+ and 0.3 micrometer Ca2+. For gerbil C the optimum pH was 8, ionic strength 0.074, and the same concentration of Mg2+ and Ca2+ as for hamster. Incubation at 37 degrees C for 60 minutes yielded optimal results. Complement components in the serum of both species could be tested with commercially prepared intermediates of sheep erythrocytes pretreated with guinea pig C1 and human C4 respectively, using purified human C2 through 9 and standard methods applied for testing human C components. Both species have all nine components of the complement system. 相似文献
3.
Rapid eye movements (REMs), EEG alpha, and tonic heart rate (HR) were measured during 6 types of cognitive tasks—imagining a liked person, suppressing thoughts of the person, searching one's mind for alternative solutions, arithmetic involving little concentration, problems involving high concentration, and choosing a preferred activity. The latter 3 required verbalization, the former 3 did not. Only suppression and search did not differ significantly from each other on at least one physiological variable. Imagining, suppression, and search yielded few REMs, high alpha, and low HR. High concentration yielded many REMs, low alpha, and high HR. Choice yielded many REMs, low alpha, and intermediate HR. Low concentration yielded few REMs, low alpha, and high HR. Suppression produced somewhat less alpha than imagining but did not differ significantly in REMs. 相似文献
4.
A low molecular weight (LMW) antigen of Eimeria tenella, initially identified using a murine monoclonal antibody (mAb C34F1) raised against E. tenella sporozoites, was partially characterized using enzymatic degradation, solvent extraction, and immunization into various inbred
lines of mice. The LMW antigen could be isolated using Folch extraction (methanol/chloroform/water) and the epitope recognized
by mAb C34F1 was resistant to degradation by α-amylase, pronase, and proteinase K, but was sensitive to sodium m-periodate treatment or digestion using mixed glycosidases (from Turbo cornutus). These observations suggest that the antigenic epitope recognized by mAb C34F1 is carbohydrate-dependent and, based on our ability to isolate the LMW antigen by Folch extraction, the epitope probably
resides on a polar glycolipid. The inability of sporozoite-immunized nude mice to elicit a serum antibody response to this
molecule indicates that it acts as a T-dependent antigen. Furthermore, sporozoite-immunized male CBA/N mice (with an X-linked
immunodeficiency) also failed to elicit a serum antibody response to this molecule, which is consistent with a carbohydrate
antigenic epitope. We propose that this antigenic molecule be designated ET-GL1 to reflect its origin and probable structure
(E. tenella glycolipid 1).
Received: 30 June 1999 / Accepted: 2 December 1999 相似文献
5.
6.
A cross-reactive monoclonal antibody (mAb), designated 1205, was used to study redistribution, parasitophorous vacuole (PV) incorporation, and in situ antigen production during the intracellular parasite development ofEimeria acervulina andE. tenella. Western-blot analysis of sporozoite preparations showed that the mAb recognized antigenic bands at 55 and 80 kDa. Indirect immunofluorescent antibody (IFA) labeling of sporozoites produced an internal dot pattern. Immunogold electron microscopy (IM) showed labeling of dense granules within sporozoites. The IFA pattern changed to a general-internal label in immature schizonts followed by a surface-tip pattern in mature merozoites both in vitro and in vivo. IM of the asexual stages revealed the same labeling pattern for the in vivo development of both species, and labeling of rhoptries was seen. In vitro, the PV membrane together with amorphous material within the PV was labeled by IFA during schizont development forE. tenella. No IM labeling of either the PV membrane or material within the PV was observed. Sexual stages seen in vivo for both species had the general-internal IFA pattern. 相似文献
7.
Jana Jedlickova Marie Vajter Tomas Barta Graeme C. M. Black Rahat Perveen Jan Mares Marek Fichtl Bohdan Kousal Lubica Dudakova Petra Liskova 《Clinical genetics》2023,104(4):418-426
Four members of a three-generation Czech family with early-onset chorioretinal dystrophy were shown to be heterozygous carriers of the n.37C>T in MIR204. The identification of this previously reported pathogenic variant confirms the existence of a distinct clinical entity caused by a sequence change in MIR204. Chorioretinal dystrophy was variably associated with iris coloboma, congenital glaucoma, and premature cataracts extending the phenotypic range of the condition. In silico analysis of the n.37C>T variant revealed 713 novel targets. Additionally, four family members were shown to be affected by albinism resulting from biallelic pathogenic OCA2 variants. Haplotype analysis excluded relatedness with the original family reported to harbour the n.37C>T variant in MIR204. Identification of a second independent family confirms the existence of a distinct MIR204-associated clinical entity and suggests that the phenotype may also involve congenital glaucoma. 相似文献
8.
The authors describe the coexistence of the carcinoid of the appendix and Crohn's disease. In the case of their woman patient the carcinoid was identified with the examination of the resected ileoascendent part of the bowel resulting of the complication of the Crohn's disease. 10 similar association is known in the literature but none of the patients had the signs of the carcinoid syndrome. Subsequent adrenerg syndrome after an alimentary hypoglycemia (increased evacuation of the cathecolamines and their metabolites in the urine), food allergy (increased IgE type antibody to milk protein) or gastroenteropancreatic (GEP) neuroendocrine tumor (based on the result of the 111In-octreoscan and the increased 5-hydroxyindolaceticaciduria) equally suspected of the symptoms (palpitation, flush) manifested after the operation. They look for the connection between the genesis of the intestinal carcinoid and the Crohn's disease with working up the bibliography. Summing up the references with a view of the latest it can be stated that the carcinoid of the appendix occurs more than orders of magnitude in the samples from inflamed surrounding than the samples from autopsy (0.24%--820/338,000 inflamed appendix and 0.03%--19/53,430 appendix from autopsy). Consequently the inflammation create favourable condition for the development of the carcinoid of the appendix. 相似文献
9.
MRI volumes of the hippocampus and amygdala in adults with Down's syndrome with and without dementia 总被引:4,自引:0,他引:4
Aylward EH Li Q Honeycutt NA Warren AC Pulsifer MB Barta PE Chan MD Smith PD Jerram M Pearlson GD 《The American journal of psychiatry》1999,156(4):564-568
OBJECTIVE: This study sought to determine whether volumes of the hippocampus and amygdala are disproportionately smaller in subjects with Down's syndrome than in normal comparison subjects and whether volume reduction is greater in Down's syndrome subjects with dementia. METHOD: The subjects were 25 adults with Down's syndrome (eight with dementia) and 25 cognitively normal adults who were individually matched on age, sex, and race. Magnetic resonance imaging measures included volumes of the hippocampus, amygdala, and total brain. Nineteen of the Down's syndrome subjects had follow-up scans (interscan interval = 9-41 months). RESULTS: Nondemented Down's syndrome subjects had significantly smaller volumes of the hippocampus, but not the amygdala, than their comparison subjects, even when total brain volume was controlled for. Volumes of both the hippocampus and the amygdala were smaller in the demented Down's syndrome subjects than in their comparison subjects, even when total brain volume was controlled for. Age was not correlated with volume of the hippocampus or amygdala among the nondemented Down's syndrome subjects and the comparison subjects; age was correlated with volume of the amygdala, but not the hippocampus, among the Down's syndrome subjects with dementia. Changes in volume over time were not statistically significant for either the demented or the nondemented subjects. CONCLUSIONS: Hippocampal volume, while disproportionately small for brain size in individuals with Down's syndrome, remains fairly constant through the fifth decade of life in those without dementia. All subjects over age 50 who had Down's syndrome demonstrated volume reduction in the hippocampus as well as clinical signs of dementia. Dementia was also associated with volume reductions in the amygdala that exceeded reductions in total brain volume. 相似文献
10.
Thomas Dierks Stefan Barta Lothar Demisch Klaus Schmeck Ekkehart Englert Andrea Kewitz Konrad Maurer Fritz Poustka 《Psychopharmacology》1999,146(1):101-107
Rationale: The intensity dependence of the auditory evoked potentials (AEP) has been suggested to be a specific biological marker of
central serotonergic activity. Objective: While previous studies used circumstantial evidence to support this hypothesis, we manipulated (decreased) cerebral levels
of serotonin directly by using tryptophan depletion. Methods: Twelve healthy young subjects were investigated using placebo and two different amino acid mixtures in a double blind cross
over design on three different occasions. AEPs recorded during tryptophan depletion were analyzed by dipole analysis and regional
sources using methods published in the literature. Results: For none of the mixtures a significant effect of tryptophan depletion was found. There was a trend towards reduced intensity
dependency after tryptophan depletion, especially in the right hemisphere. This reduction correlated with the amount of reduced
tryptophan in plasma. Conclusions: The results indicate, in contrast to earlier indirect studies, that the intensity dependence of AEPs is not a specific marker
of central serotonergic activity.
Received: 8 March 1999 / Final version: 25 May 1999 相似文献