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51.
The evolutionary conservation of brain Thy-1 glycoprotein in 24 vertebrate and invertebrate species has been investigated by means of a soluble phase radioimmunoassay (RIA) and by the "Western blot" technique. The brain glycoproteins from virtually all the vertebrate species inhibited the precipitation of mouse Thy-1.1 by a rabbit anti-rat Thy-1 antiserum. Most reagents also inhibited the binding of a mouse anti-rat Thy-1 monoclonal antibody to rat Thy-1. Whole tissue glycoproteins from earthworm, snail and oyster and ganglia glycoproteins of a locust species were also found to be inhibitory. Western blotting analysis on NaDod SO4 polyacrylamide gel electrophoresis under reducing conditions revealed a Thy-1 homologous molecule (22-25 KD) in mammals, birds, fish, reptiles and invertebrate species. The snail Thy-1-like molecule was eluted from the gel and was shown to specifically inhibit the serological reaction. The rabbit anti-rat Thy-1 antiserum also detected a doublet molecule of approximately 85,000 KD, which is conserved in all species, including yeast and bacteria. The origin and nature of the presumed glycoproteins is unknown. Our results suggest that the Thy-1 molecule has been conserved throughout metazoan evolution and that the Thy-1 gene is the most conserved among the immune related genes (immunoglobulins, beta 2-microglobulin and major histocompatibility) which share extensive amino acid homology.  相似文献   
52.
BACKGROUND: If a validated questionnaire, when applied to patients reporting with symptoms of intermittent claudication, could adequately discriminate between those with and without peripheral arterial disease, GPs could avoid the diagnostic measurement of the ankle brachial index. AIM: To investigate the Edinburgh Claudication Questionnaire (ECQ) in general practice and to develop a clinical decision rule based on risk factors to enable GPs to easily assess the likelihood of peripheral arterial disease. DESIGN OF STUDY: An observational study. SETTING: General practice in The Netherlands. METHOD: This observational study included patients of > or =55 years visiting their GP for symptoms suggestive of intermittent claudication or with one risk factor. The ECQ and the ankle brachial index were performed. The prevalence of peripheral arterial disease, defined as an ankle brachial index <0.9, was related to risk factors using logistic regression analyses, on which a clinical decision rule was developed and related to the presence of peripheral arterial disease. RESULTS: Of the 4790 included patients visiting their GP with symptoms suggestive of intermittent claudication, 4527 were eligible for analyses. The prevalence of peripheral arterial disease in this group was 48.3%. The sensitivity of the ECQ was only 56.2%. The prevalence of peripheral arterial disease in a clinical decision rule that included age, male sex, smoking, hypertension, hypercholesterolemia, and a positive ECQ, increased from 14% in the lowest to 76% in the highest category. CONCLUSION: This study indicates that the ECQ alone has an inadequate diagnostic value in detecting patients with peripheral arterial disease. The ankle brachial index should be performed to diagnose peripheral arterial disease in patients with complaints suggestive of intermittent claudication, although our clinical decision rule could help to differentiate between extremely high and lower prevalence of peripheral arterial disease.  相似文献   
53.
54.
This article presents an integrated conception of the self based on cognitive and interpersonal theories. Implications for clinical practice are outlined, which include understanding the therapeutic relationship as a laboratory and change as involving self-expansion. Implications for clinical research are also presented and exemplified by two strategies, which are demonstrated in a single case study of a patient who successfully underwent a brief-term treatment. The first involves the use of Interpersonal Scenarios, which are structured idiographic vignettes scaled on several parameters, to measure change between psychotherapy sessions. The second involves the use of the Structural Analysis of Social Behavior, a measure of interpersonal process, and the Experiencing Scale, a measure of emotional involvement, to measure change within a session.  相似文献   
55.
A mouse model of galactose-induced cataracts   总被引:4,自引:0,他引:4  
Galactokinase (GK; EC 2.7.1.6) is the first enzyme in the metabolism of galactose. In humans, GK deficiency results in congenital cataracts due to an accumulation of galactitol within the lens. In an attempt to make a galactosemic animal model, we cloned the mouse GK gene (Glk1) and disrupted it by gene targeting. As expected, galactose was very poorly metabolized in GK-deficient mice. In addition, both galactose and galactitol accumulated in tissues of GK-deficient mice. Surprisingly, the GK-deficient animals did not form cataracts even when fed a high galactose diet. However, the introduction of a human aldose reductase transgene into a GK-deficient background resulted in cataract formation within the first postnatal day. This mouse represents the first mouse model for congenital galactosemic cataract.  相似文献   
56.
Sera from military personnel found to have antibodies to hepatitis B surface antigen (anti-HBS) in an epidemiological study of a hepatitis B outbreak were tested for persistence of that antibody 1 year later. Initially, 64% of the anti-HBS-positive sera reacted in passive hemagglutination tests with erythrocytes coated with hepatitis B surface antigen of both ayw and adw subtypes; the remaining sera reacted only with adw-coated erythrocytes (19%) or ayw-coated erythrocytes (17%). After 1 year, anti-HBS was detectable by passive hemagglutination tests in 87% of individuals with initial antibody to both subtypes but in only 41% and 16% (P less than 0.001) of those initially reacting only to adw- or ayw-coated erythrocytes, respectively. Seropositivity for anti-HBS correlated best with history of contact with jaundiced people (20.3%) and duty in Asia.  相似文献   
57.
Regulation of interleukin 1 generation in immune-activated fibroblasts   总被引:1,自引:0,他引:1  
In the present study we have demonstrated that fibroblasts can generate the inflammatory cytokine interleukin 1 (IL 1) under conditions similar to those abundant in cellular immune responses. Thus, induction of IL 1 requires a sequential two-step protocol which consists of preactivation of mouse embryo fibroblasts (MEF) with crude preparations of T cell or macrophage-derived conditioned media (CM; 72 h), followed by a challenge with lipopolysaccharide (LPS; 24 h). Unstimulated fibroblasts or such cells activated by either CM or LPS produced only low levels of IL 1, while a synergism between both signals was observed for obtaining maximal IL 1-like activity in MEF. Each of a series of individual recombinant lymphokines and cytokines (IL 2, granulocyte/macrophage-colony-stimulating factor, tumor necrosis factor, IL 1 beta and interferons-alpha, beta and gamma) was shown to serve as an efficient priming signal for the induction of IL 1. IL 1-like activity in fibroblasts was detected in cell lysates or associated with the producing-cell membrane but not in culture fluids. Immune-stimulated fibroblasts, activated under such experimental conditions, were shown to actively transcribe mRNA of both IL 1 genes (alpha and beta). For the expression of IL 1-specific mRNA in fibroblasts a single stimulus, provided by either LPS or a lymphokine/cytokine, was sufficient; however, a more intense signal was observed when both stimuli were applied. The IL 1-like biological activity of fibroblast origin was significantly reduced by anti-IL 1 alpha antibodies. Thus, fibroblasts, when activated by immune and bacterial products, generate IL 1 which in turn possibly amplifies cellular immune responses or inflammatory processes in connective tissues.  相似文献   
58.
The kinetics of a model reaction between the antitumor drug cis-diamminedichloroplatinum(II)(cis-DDP) and the signal nucleotide diadenosine 5',5"'-P1,P4-tetraphosphate (Ap4A) has been investigated by spectrophotometry. The formation of the reactive platinum aquated species was first analyzed by potentiometry using a chloride-specific electrode. Both equilibrium and rate constants were measured. The rate constants for the release of the first and second chloride were found 1.1 +/- 0.5 (S.D.) X 10(-4) and 4.2 +/- 0.2 X 10(-5) sec-1, respectively, at 37 degrees. It was shown that anions such as acetate, phosphate, and pyrophosphate were able, in some conditions, to exchange with chloride to form acetato, phosphato, or pyrophosphato complexes. The reaction of cis-DDP with Ap4A or other targets involves at least four steps, which have been analyzed separately. The values of rate constants deduced from the analysis of the overall reaction are in agreement with those determined independently from the separated steps. The second-order rate constants for the reaction of acetato, phosphato, and pyrophosphato complexes with Ap4A (0.2 +/- 0.02, 0.20 +/- 0.02, and 0.16 +/- 0.03 M-1 sec-1, respectively) are close to that of monoaqua-monochloro (0.16 +/- 0.1 M-1 sec-1) and lower than that of the diaqua species (0.94 +/- 0.06 M-1 sec-1). At a high concentration of Ap4A, the reaction kinetics is slowed down. The formation of a complex of cis-platinum with the Ap4A phosphate groups is suggested. The intracellular concentration of phosphates, pyrophosphates, and carboxylates is large enough to displace chloride from cis-DDP. Inside cells, therefore, ligand exchange processes have to be taken into account to analyze the in vivo reactivity of cis-DDP with its potential targets.  相似文献   
59.
Electrophysiological and cytofluorometric data suggest that doses of amphetamine which enhance locomotor activity and promote focused stereotypies produce pronounced effects on serotonin pathways in the CNS. However, the biochemical evidence regarding changes in serotonergic function produced by moderate doses of this drug is inconsistent. Therefore, the present study was designed to further examine the effects of amphetamine (1–5 mg/kg) on regional brain serotonin and its metabolite and to compare these effects to behaviorally comparable doses of methylphenidate and apomorphine. At doses which produce a multiphasic behavioral response pattern, including a stereotypy phase consisting primarily of repetitive head movements and occasional oral stereotypies, amphetamine (3 mg/kg) and methylphenidate (30 mg/kg) increased levels of 5HIAA in striatum and frontal cortex, two brain regions which receive serotonergic projections from the dorsal raphe nucleus. In contrast, these drugs decreased or had no effect on 5HIAA levels in hippocampus, a brain region which receives its serotonergic innervation from the median raphe nucleus. A moderate dose of apomorphine (0.5 mg/kg) produced a comparable pattern of neurochemical effects. These data are consistent with electrophysiological and cytofluorometric data suggesting enhanced dorsal raphe serotonergic function following amphetamine-like stimulants. Pretreatment of animals with -methyltyrosine at a dose sufficient to prevent the locomotor stimulation and stereotypy promoted by amphetamine, or by haloperidol, failed to prevent the amphetamine-induced increase in 5HIAA, indicating that these serotonergic effects are not secondary to the amphetamine facilitation of dopaminergic transmission. The results of this study suggest that serotonin may play a modulatory role in the behavioral effects of amphetamine-like stimulants which is dependent for its expression on an intact dopamine system.Abbreviations DA dopamine - AMPH S(+)amphetamine - 5HT serotonin - MP methylphenidate - APO apomorphine - 5HIAA 5-hydroxyindoleacetic acid - MT -methyltyrosine - DOPAC 3,4-dihydroxyphenylacetic acid - HVA homovanillic acid - HAL haloperidol  相似文献   
60.
Two patients with true synovial cysts in atypical sites (internal compartment of knee and inguinal hollow) were investigated by radioarthrography, ultrasound and computed tomography imaging. The cyst in the hip region originated from a dilated serous bursa of the iliopsoas muscle that did not communicate or was no longer in communication with the joint. In contrast, the cyst of the knee appeared to be a lateral synovial capsule hernia. Positive diagnosis in both cases was dependent on combined ultrasound-CT scan imaging, this eliminating a tumor (sarcoma) of soft tissues. However, affirmation of the synovial origin (mesothelial covering of the wall) of the lesion was obtained by histology only, this allowing differentiation from a "capsular" (fibrous wall) cyst, which probably provokes similar ultrasound and CT scan images.  相似文献   
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