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1.
Using indirect immunohistochemistry and an antiserum raised against rat corticotrophin-releasing factor (CRF) we have outlined an asymmetric network of cells and varicose fibers in sheep adrenal cortex. This network was not associated with the larger splanchnic nerves, but was occasionally found in small bundles or with blood vessels; in most instances fibers were found weaving independently through cortical parenchyma. A plexus of fibers was found in the zona reticularis, with a few fibers ramifying into adjacent medulla. Uni or bipolar cells were found throughout the cortex, with the greatest frequency at the corticomedullary junction; a multipolar-type cell was also found in this area. Staining of varicose structures and most cells was abolished by incubation with excess rat CRF 1-41, but not by ovine CRF or a range of other peptides. Though the immunoreactive species has not as yet been identified, it may thus share homology with sequences present in rat but not ovine CRF. 相似文献
2.
Factors influencing women to undergo screening mammography 总被引:2,自引:0,他引:2
3.
The long-term consequences for infants with problems of feeding and crying behavior remain unknown. The purpose of this research was to determine whether such children are later perceived by their parents as vulnerable and more often have behavior problems and have different personalities than children without problems in infancy. The implications of managing such problems by changing milk formulas is explored. Mothers of 379 infants were enrolled in the postpartum period. Information about problems of feeding and crying behavior was obtained at 4 months. Thirty-six percent of the infants had problems and the formula had been changed for 17%. At 3 1/2 years, 320 (84%) mothers completed a questionnaire. Children who had had problems were more often perceived as vulnerable (relative risk [RR] 1.86; 95% confidence interval [CI] 1.09, 3.19) and more often had behavior problems (RR 1.78; 95% CI 1.03, 3.07). There were no differences in personality. Children whose problems had been managed by changing milk formulas were more often perceived as vulnerable (RR 2.18; 95% CI 1.05, 4.53). Although allergies were reported significantly more often for those children who had had problems, there were no differences in the prevalence of asthma or eczema. Problems of feeding and crying behavior in early infancy and the way they are managed may have long-term implications for the child. 相似文献
4.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
5.
6.
Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
7.
P E Rafuse C L Canny 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》1992,27(4):189-193
A 21-year-old man presented with an acute life-threatening illness that was diagnosed and treated as thrombotic thrombocytopenic purpura. The patient survived and during his recovery noted that his central vision was markedly impaired in both eyes. An ophthalmologic examination showed inflammatory and ischemic changes in the retinal vasculature consistent with a diagnosis of systemic lupus erythematosus (SLE). Review of the patient's clinical and laboratory findings did in fact support a diagnosis of SLE that was negative for antinuclear antibody but positive for anticardiolipin antibody. The authors discuss the importance of an ophthalmic examination in patients with SLE-like syndromes and the significance of positivity for anticardiolipin antibody and other antiphospholipid antibodies in patients with thrombosis in the eye or elsewhere. 相似文献
8.
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
9.
10.
Frequent administration by inhalation of salbutamol and ipratropium bromide in the initial management of severe acute asthma in children 总被引:1,自引:0,他引:1
J Reisman M Galdes-Sebalt F Kazim G Canny H Levison 《The Journal of allergy and clinical immunology》1988,81(1):16-20
A study was performed to compare the efficacy and safety of two therapeutic regimens for the treatment of children presenting to the emergency department with acute asthma. A regimen of inhaled salbutamol alone was compared to inhaled salbutamol combined with ipratropium bromide. Twenty-five children ranging in age from 5 to 15 years were enrolled in the study. Children with FEV1 less than or equal to 55% predicted were eligible to participate in the study. Subjects were randomized in a double-blind fashion into one of two treatment groups. Both groups received an initial dose of salbutamol by nebulizer of 150 micrograms/kg (0.03 cc/kg), followed by six consecutive doses of 50 micrograms/kg (0.01 cc/kg) at 20-minute intervals. In one group of subjects, 250 micrograms (1.0 ml) of ipratropium bromide respirator solution was added to the salbutamol administered at the time of the initial inhalation, and at 40 and 80 minutes, whereas the remaining subjects received a placebo with salbutamol at those times. Formal one-way statistical ANOVA with change in percent predicted FEV1 as a response variable confirmed there was a statistically significant difference at all time points caused by drug regimen during the 150-minute observation period. There was no significant difference in side effects reported in the two groups. Significant additional bronchodilation achieved with salbutamol and ipratropium bromide together indicates that there is likely a substantial cholinergic element to the bronchospasm observed in acute exacerbations of asthma in the pediatric age group. 相似文献