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101.
Human immunodeficiency virus binds to CD4 T lymphocytes by interaction between its envelope glycoprotein gpl20 and the CD4 molecule. The latter is non-covalently associated with a src-related tyrosine kinase, p56lck. CD4 cross-linking increases the activity of p56lck, leading to phosphorylation of several cellular substrates. We report here that gpl60/120 increases both the autophos-phorylation of p56lck and its enzymatic activity (reflected by phosphorylation of an exogeneous substrate) in normal T cells and the HUT78 CD4+ T cell line. This effect was detectable 5 min after activation and persisted for 40 min in normal T cells. It did not require gpl20 cross-linking and was associated with phosphorylation of tyrosine residue on several proteins, as shown by phosphotyrosine Western blot analysis. The pattern of proteins phosphorylated on tyrosine residues in response to gpl20 activation was distinct from that induced by anti-CD4 antibodies. p56lck activation required its association with CD4, since p56lck activity was not modified in HUT78 T cell lines expressing a truncated or mutated form of CD4 unable to associate with p56lck. Peptides mimicking residues 418 to 434 and 449 to 464 of HIV-1 Bru gpl20, regions known to participate in gpl20 binding to CD4, also increased p56lck activity and triggered phosphorylation of similar substrates. Taken together, these results show that gpl60/120 and derived peptides can transiently increase p56lck activity without the need for CD4 cross-linking. This activation led to a specific pattern of tyrosine phosphorylation on cellular proteins that may be of significance in the biological effects of the gpl20/CD4 interaction, e.g. syncytium formation and inhibition of T cell activation.  相似文献   
102.

Background  

Although back pain is the most common reason patients use complementary and alternative medical (CAM) therapies, little is known about the willingness of primary care back pain patients to try these therapies. As part of an effort to refine recruitment strategies for clinical trials, we sought to determine if back pain patients are willing to try acupuncture, chiropractic, massage, meditation, and t'ai chi and to learn about their knowledge of, experience with, and perceptions about each of these therapies.  相似文献   
103.
104.
Evolution of sleep and sleep EEG after hemispheric stroke   总被引:3,自引:0,他引:3  
The evolution of subjective sleep and sleep electroencephalogram (EEG) after hemispheric stroke have been rarely studied and the relationship of sleep variables to stroke outcome is essentially unknown. We studied 27 patients with first hemispheric ischaemic stroke and no sleep apnoea in the acute (1-8 days), subacute (9-35 days), and chronic phase (5-24 months) after stroke. Clinical assessment included estimated sleep time per 24 h (EST) and Epworth sleepiness score (ESS) before stroke, as well as EST, ESS and clinical outcome after stroke. Sleep EEG data from stroke patients were compared with data from 11 hospitalized controls and published norms. Changes in EST (>2 h, 38% of patients) and ESS (>3 points, 26%) were frequent but correlated poorly with sleep EEG changes. In the chronic phase no significant differences in sleep EEG between controls and patients were found. High sleep efficiency and low wakefulness after sleep onset in the acute phase were associated with a good long-term outcome. These two sleep EEG variables improved significantly from the acute to the subacute and chronic phase. In conclusion, hemispheric strokes can cause insomnia, hypersomnia or changes in sleep needs but only rarely persisting sleep EEG abnormalities. High sleep EEG continuity in the acute phase of stroke heralds a good clinical outcome.  相似文献   
105.
Results from a genome-wide screen of 10 multiplex families ascertained through probands with nonsyndromic cleft lip with or without cleft palate (CL/P) in Mexico, Argentina, and the United States yielded suggestive evidence of linkage to chromosomes 2, 6, 17 and 18. Fine mapping excluded all regions except chromosome 2. Subsequent analysis was performed on the original 10 families plus an additional 16 families using 31 markers on chromosome 2. This analysis showed intriguing evidence of linkage to 2q (Zlr=2.26, empirical P-value=0.028 in a chromosome-wide analysis). Transmission disequilibrium tests also revealed evidence of linkage and disequilibrium for two markers in this region (D2S168 and D2S1400 with P-values=0.022 and 0.006, respectively). A subset of these 26 families provided additional evidence for a susceptibility gene for CL/P on 2q, suggesting that further studies of genes in this region are warranted.  相似文献   
106.
The contributions of changes in cognitions (degree of belief in automatic thoughts) and the patient's relationship with his therapist to mood changes occurring during sessions of cognitive therapy were examined in data collected from 17 depressed and anxious patients. Results showed that both changes in automatic thoughts and the patient's relationship with his therapist made independent, additive contributions to mood changes. In addition, two patient characteristics (initial degree of belief in automatic thoughts and diagnosis) made significant unique contributions to mood changes. The stronger the patient's initial belief in his automatic thoughts, the smaller the mood change occurring in the session. Smaller mood changes also occurred in patients with a personality disorder diagnosis. These results suggest that mood changes in cognitive therapy sessions are a function of three types of factors: technical cognitive therapy interventions, the patient's relationship with his/her therapist, and patient characteristics. A multiple regression model with independent variables measuring these factors accounted for 89% of the variance in mood change in the session.We thank our patients for their generous contributions. Anna Rose Childress and Juli Kinchla contributed to the inception of the study. We thank Jeffrey M. Perloff for advice concerning the statistical analysis. Jonathan Baron, Susan Krantz, Ricardo Muõz, S. Lloyd Williams, and the anonymous reviewers gave helpful comments on an earlier draft. This paper was presented at a meeting of the Society for Psychotherapy Research, Lake Louise, Canada, June 1984.  相似文献   
107.
Prevention Science - We examined whether participation in adolescent substance use prevention programming can enhance long-term resilience into adulthood such that individuals were better able to...  相似文献   
108.
This is a review of randomized controlled trials using docosahexaenoic acid (DHA) interventions in the first 1000 days of life with assessments of behavioral functioning in childhood. Electronic databases were searched for trials with a DHA intervention (compared with a placebo group that received no or less DHA) at any time to either women or infants during the first 1000 days, with a subsequent assessment of child behavior. There were 25 trials involving 10,320 mother–child pairs, and 71 assessments of behavior in 6867 of the children (66.5% of those originally enrolled). From the 71 assessments administered, there were 401 comparisons between a DHA group and a control group, with most reporting a null effect. There were no findings of a positive effect of DHA, and 23 instances where the DHA group had worse scores compared with the control group. There was limited evidence that DHA supplementation had any effect on behavioral development, although two of the largest trials with behavioral measures detected adverse effects. Future trials, and future follow-ups of existing trials, should make an effort to evaluate the effect of DHA intervention on behavioral functioning.  相似文献   
109.
Maternal and Child Health Journal - To assess university students’ knowledge of reproductive health information about miscarriage. A single-centre, cross-sectional study was carried out using...  相似文献   
110.
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