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11.
The ability of the SP fragments SP2–11 and SP3–11 to release histamine from rat peritoneal mast cells has been compared with that of the whole peptide. SP1–11 was found to be about 3.4 times more active than SP2–11 and about 10.4 times more active than SP3–11. The substance P antagonist [D-Pro4, D-Trp7,9,10] SP4–11 was equally effective at antagonizing the histamine releasing action of SP1–11, SP2–11 and SP3–11. Benzalkonium chloride was found to be a competitive antagonist of SP and SP3–11: the dissociation constants for the benzalkonium chloride-receptor interaction being about the same when either SP1–11 or SP3–11 was used as the agonist. 相似文献
12.
Psychological differentiation, psychophysiological arousal, hearing capacity, and ability to lipread unrelated sentences presented in a silent technicolor film were investigated in 62 children (mean age 10 years, 4 months), classified into three hearing categories (normal, mild to moderate hearing loss, severe hearing loss) based on their average hearing threshold in the range of speech frequencies for their best ear. All subjects were administered the Rod and Frame Test, Craig Lipreading Inventory, and skin conductance measures under two conditions (pre-task and task). The results showed that the ability to lipread sentences from a film was related significantly to psychological differentiation (cognitive style) and pre-task conductance level, but was not related to hearing capacity or task conductance level. The best predictors of lipreading ability were successful performance on the Rod and Frame Test and high increases in skin conductance from pre-task to task situation. 相似文献
13.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
14.
Eleven elderly confused patients were given a single dose of chlormethiazole, temazepam and placebo on separate nights with-in a 10-day period. There was no statistically significant difference between the three treatments the next morning in any of the tests, which included subjective and objective measures of mental ability, orientation and hangover effect. These results mirror those previously found in normal, healthy, elderly patients, and do not therefore support the contention that hypnotics increase confusion in demented patients, or that such patients are more sensitive to their actions. Indeed, plasma drug concentrations were on average twice as high in demented as in normal elderly subjects, thus raising the possibility of decreased sensitivity in the demented group. There was little correlation between plasma concentration and pharmacological effect. 相似文献
15.
Cloning, sequencing, and expression of a gene from Campylobacter jejuni encoding a protein (Omp18) with similarity to peptidoglycan-associated lipoproteins.
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A Campylobacter jejuni genomic plasmid library was screened with antiserum generated against whole C. jejuni, revealing two immunoreactive clones. Sequence analysis of the recombinant plasmids revealed a common open reading frame of 498 nucleotides encoding a protein of 165 amino acids with a calculated molecular mass of 18,018 Da. The recombinant product partitioned to the outer membrane fractions of Escherichia coli transformants and has been designated Omp18. The deduced amino acid sequence of the cloned C. jejuni gene exhibits considerable similarity to peptidoglycan-associated lipoproteins from other gram-negative bacteria. 相似文献
16.
In a child with some features of Turner's syndrome, gonosomal mosaicism with an isodicentric nonfluorescent (idic)Y chromosome was detected (mos 45,X/47,X,idic(Y)(q11),idic(Y)(11)/46,X,idic(Y)(q11)). Histopathological examination showed streak gonads with some evidence of ovarian stroma and no sign of gonadoblastoma. Polymerase chain reaction (PCR) analysis in blood lymphocytes and gonadal tissues using primers of seven loci along the Y chromosome, including the sex determined region (SRY), azoospermia factor region (AZF) and the deleted in azoospermia ( DAZ ) gene was positive for all loci tested, confirming the isodicentric character of the Y chromosome and indicating the presence of the AZF region. It is remarkable that the existence of spermatogenesis controlling genes does not play an important role in gonadal development and differentiation in a phenotypic female with some Turner stigmata. The data presented here are briefly discussed with previously-described patients. 相似文献
17.
Temperament as a potential predictor of mortality: Evidence from a 41-year prospective study 总被引:3,自引:0,他引:3
Pirkko L. Graves Lucy A. Mead Nae-Yuh Wang Kung-Yee Liang Michael J. Klag 《Journal of behavioral medicine》1994,17(2):111-126
Psychological factors were hypothesized to influence mortality, in particular, early versus later mortality. To explore the relationship between temperament, a psychological factor, and mortality in a prospective study of 1337 medical students, we constructed a measure portraying three temperament types, using latent class analysis. Death occurred in 113 subjects over 25–41 years of follow-up. In univariate survival analysis, subjects tending to direct tension inward when under stress (Tension-In) had a higher risk of mortality than Tension-Out or Stable types. These associations persisted after adjustment for age, smoking, cholesterol level, and Quetelet Index. The relative risk (RR) of mortality for Tension-In was 1.56 (95% confidence interval, 1.00–2.44) compared with the Stable group. The risk was due entirely to the excess risk in persons under 55 years of age (RR, 2.59; 95% confidence interval, 1.46–4.62); the corresponding risk of death in older persons was 0.66 (0.30–1.48). Thus temperament is a significant risk factor for mortality, in particular, premature death. 相似文献
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R A Cattan P P Barry G Mead W E Reefe A Gay M Silverman 《Journal of the American Geriatrics Society》1990,38(7):753-758
Medical records of 81 older patients (65 years of age and over) who underwent electroconvulsive therapy (ECT) at a university-affiliated private geriatric hospital were reviewed to evaluate the safety and efficacy of this treatment for depression in the "young-old" (65 to 80 years) compared with the "old-old" age group (over 80 years), a group that has not yet been adequately studied. Information was obtained regarding demographics, medical and psychiatric diagnosis, medications, indications for ECT, number and laterality of treatments, outcome, and complications. Thirty-nine patients 80+ years of age (mean age, 85 +/- 3.2) were compared with 42 patients 65 to 80 years of age (mean age, 74 +/- 5.2). Statistical analysis was performed using confidence intervals of the difference in proportions of patients in each group. There were no significant differences in the demographics, number and laterality of ECT treatments, indications for ECT treatment, medical diagnosis, medications, or prior history of falls, but psychiatric diagnoses differed slightly. Patients over 80 years had significantly more cardiovascular complications and falls (95% confidence interval) and tended to have a worse ASA (American Society of Anesthesiologists) scale rating and a somewhat less successful outcome. This study confirms the role of ECT as a relatively safe and effective treatment, which may be lifesaving in selected depressed older patients. Prospective studies are needed to understand better the long-term outcome and to prevent the morbidity and mortality associated with ECT in this frail, high-risk older group. 相似文献