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排序方式: 共有624条查询结果,搜索用时 500 毫秒
161.
162.
Gender and the sudden infant death syndrome 总被引:1,自引:0,他引:1
Abstract A nationwide case-control study compared the prevalence and magnitude of risk factors for sudden infant death syndrome (SIDS) in male and female infants. The risk factors of SIDS and their magnitude for males and females are very similar. After adjustment for potential confounders male infants had a 1.42-fold (95% CI = 1.04, 1.94) increased risk of SIDS compared with females. Risk factors identified in most epidemiological studies are not the reason for the increased SIDS mortality seen in male infants. 相似文献
163.
WJ Rodriguez WC Gruber JR Groothuis EA Simoes AJ Rosas M Lepow A Kramer V Hemming 《Pediatrics》1997,100(6):937-942
OBJECTIVE: To evaluate the efficacy of high titer respiratory syncytial virus (RSV) immune globulin (RSVIG) in the treatment of previously healthy children hospitalized with proven RSV lower tract infection (LRI). METHOD: Infants and young children =2 years of age with RSV LRI of =4 days duration, and respiratory scores >/=2. 5 were enrolled. RESULTS: One hundred and one previously healthy children hospitalized with RSV LRI received either 1500 mg/kg of RSVIG (RespiGam, MedImmune Inc, Gaithersburg, MD) or albumin placebo in a randomized, double-blind, placebo-controlled trial. Forty-six RSVIG and 52 recipients of placebo met all eligibility criteria. Demographic characteristics of the two groups were similar. More RSVIG recipients (46% vs 29%) had an SaO2 =85% at entry than did placebo recipients, but a higher proportion of placebo recipients required intensive care unit (ICU) care and mechanical ventilation at study entry. The mean RSV hospital stay was 5.52 +/- 0.69 days (SE) for placebo and 4.58 +/- 0.40 days for RSVIG. Additionally, there was an interaction between treatment group and entry respiratory score, which led to subgroup analysis. Children with modest respiratory illness did not receive any benefit from RSVIG therapy. RSVIG recipients with more severe illness (entry respiratory scores >/=3.0) had 1.6 fewer hospital days and 2.7 days less ICU stays. CONCLUSION: RSVIG infusions seemed safe and generally well tolerated. Although some beneficial effect trends were seen for those with more severe disease who were treated there was no evidence that treatment with RSVIG resulted in reduced hospitalization and reduced ICU stays in all children with RSV disease. 相似文献
164.
RP Ford EA Mitchell AW Stewart R Scragg BJ Taylor 《Archives of disease in childhood》1997,77(1):54-55
One component of the Back to Sleep campaign to reduce the risk of sudden infant death syndrome (SIDS) is the recommendation that parents seek medical attention if their infant is unwell. The aim of this study was to investigate of SIDS could in part be explained by sick infants not getting appropriate medical care. Data on symptoms of illness and on acute medical contacts made for infants dying from SIDS (n = 390) within two weeks of their death were compared with those from a randomly selected group of control infants (n = 1592). SIDS cases had more severe illness than controls (odds ratio (OR) = 3.43; 95% confidence interval (CI) = 1.69 to 5.38), and were more likely to have seen a general practitioner (OR = 1.37; 95% CI = 1.09 to 1.73) or attended hospital (OR = 3.43, 95% CI = 1.09 to 1.73). Only 1.3% of all SIDS cases had symptoms suggesting severe illness and had not seen a general practitioner. A lack of medical contacts in the two weeks before death does not contribute to the risk of SIDS. 相似文献
165.
Martin EA; Heydon RT; Brown K; Brown JE; Lim CK; White IN; Smith LL 《Carcinogenesis》1998,19(6):1061-1069
A novel HPLC system has been developed that has allowed the separation of
tamoxifen DNA adducts formed in the livers of rats and mice treated with
this drug. At least 13 different peaks have been separated from
32P-post-labelled DNA, with two major peaks jointly accounting for >60%
of the total adducts formed by tamoxifen in the livers of treated rats and
mice. This is a great improvement on the resolution obtained by thin layer
chromatography, which separates the adducts into one main product
consisting of a group of major adduct spots eluting together, plus several
other minor spots. Identification of the nature of some of the peaks has
been investigated. Comparisons of the products formed when
alpha-acetoxytamoxifen is reacted with DNA in vitro with 32P-post- labelled
liver DNA adducts from rats treated with tamoxifen or alpha-
hydroxytamoxifen in vivo, appear to confirm that a major route of
activation of tamoxifen in vivo is via alpha-hydroxylation. The resolving
power of this HPLC system has further extended this result to show that six
of the peaks, including the two major peaks, are formed by the reaction of
an activated alpha-hydroxytamoxifen with DNA. Activation of
4-hydroxytamoxifen by the peroxidase/H2O2 system in vitro gives a more
polar DNA adduct seen only at trace levels in liver DNA from
tamoxifen-treated rats and mice.
相似文献
166.
MA Gatzoulis ML Rigby EA Shinebourne AN Redington 《Archives of disease in childhood》1995,73(1):66-69
The purpose of this study was to compare contemporary results of balloon dilatation and surgery for valvar aortic stenosis in infants and children in the five years between August 1988 and October 1993. Thirty four children underwent attempted balloon valvuloplasty (age 1 day-16 years, weight 1720 g-68 kg) (group 1), eight of whom were neonates with critical aortic stenosis. During the same period, 17 children underwent direct surgical valvotomy (group 2) (seven neonates). Successful balloon valvuloplasty was achieved in 33 (97%) with immediate reduction in the instantaneous systolic pressure gradient from 82 to 34 mm Hg (mean). There were two deaths in this group (both neonates), the second in a preterm neonate from necrotising enterocolitis. Complications requiring intervention in group 1 were aortic regurgitation in one and femoral artery injury in two. Follow up from four months to five years showed sustained results in most cases. There were two neonatal deaths in the surgical group. When the two groups were compared there was no significant difference in mortality, morbidity, or need for reintervention within 12 months. Deaths from both groups were attributed to small left ventricles. Hospital stay was significantly shorter in group 1. It is concluded that balloon dilatation for valvar aortic stenosis is effective and safe for the entire paediatric population. The results compare favourably with those of surgery. 相似文献
167.
Whole-cell patch clamp recordings were made from neurons of the rat subpostremal region of the nucleus tractus solitarius (NTS) in transverse brainstem slices. Neurotensin (NT) enhanced the firing rate of action potentials from 0.8 +/- 0.4 Hz in control to 1.9 +/- 1.3 Hz (n = 9) and increased their decay time. The peak amplitude of the after-hyperpolarization was decreased by 34+/-5% (n = 9). These effects were associated with a depolarization of 4 +/- 1 mV (n = 10) in the resting membrane potential and an increase in the input resistance (from 768 +/- 220 MOmega to 986+/-220 MOmega; n = 5) and were compensated by manually hyperpolarizing the cell to control values. In voltage clamp experiments NT decreased an outward current (from 488 +/- 161 to 340 +/- 96 pA at +40 mV; n = 5) which reversed near the potassium equilibrium potential. In addition, NT increased the frequency of both excitatory and inhibitory spontaneous synaptic currents, an effect blocked by tetrodotoxin, and did not change the evoked excitatory or inhibitory postsynaptic currents. The selective NTR1 receptor antagonist SR48692 reversibly blocked the effects of NT on both action potentials and spontaneous synaptic currents. Our results suggest that NTR1 receptors can modulate post-synaptic responses in neurons of the subpostremal NTS by increasing cell excitability as a result of blockade of a potassium conductance. 相似文献
168.
FMR2 expression in families with FRAXE mental retardation 总被引:1,自引:3,他引:1
Gecz J; Oostra BA; Hockey A; Carbonell P; Turner G; Haan EA; Sutherland GR; Mulley JC 《Human molecular genetics》1997,6(3):435-441
169.
Fu K; Hartlen R; Johns T; Genge A; Karpati G; Shoubridge EA 《Human molecular genetics》1996,5(11):1835-1840
A novel mtDNA point mutation was detected in the tRNAleu(CUN) gene (G to A
at position 12315) in a sporadic patient with chronic progressive external
ophthalmoplegia, ptosis, limb weakness, sensorineural hearing loss and a
pigmentary retinopathy. The mutation disrupts base pairing in the T psi C
stem at a site which has been conserved throughout evolution. Although the
other mtDNA tRNAleu gene (UUR) is a hotspot for mutation, this is the first
pathogenic mutation to be reported in the gene coding for tRNAleu(CUN).
MtDNAs carrying the mutation constituted 94% of total mtDNAs in two
separate muscle biopsies. Single fibre analysis showed that skeletal muscle
fibres without detectable cytochrome c oxidase activity (COX-ve fibres)
contained predominantly mutant mtDNAs (93-98%) while fibres with apparently
normal COX activity had up to 90% mutant mtDNAs, demonstrating that the
G12315A mutation is functionally recessive. Immunofluorescence studies with
specific antibodies to mtDNA- or nuclear-encoded subunits of COX were
consistent with a defect in mitochondrial protein translation. The mutation
was not present in blood cells or cultured fibroblasts and surprisingly, it
could not be detected in satellite cells cultured from the patient's
muscle. This pattern, which may by typical of patients who have inherited
new germline pathogenic mtDNA mutations, possibly reflects loss of the
mutation by random genetic drift in mitotic tissues and proliferation of
mitochondria containing the mutant mtDNA in post- mitotic cells. The
absence of mtDNA carrying the mutation in satellite cells suggests that
regeneration of skeletal muscle fibres from satellite cells could restore a
wild-type mtDNA genotype and normal muscle function.
相似文献
170.
Replicative segregation of mitochondrial DNA (mtDNA) can produce large
differences in the proportions of wild-type and mutant mtDNAs in different
cell types of patients with mitochondrial encephalomyopathy. This is
particularly striking in the skeletal muscle of patients with Kearns-Sayre
syndrome (KSS), a sporadic disease associated with large- scale mtDNA
deletions, and in sporadic patients with tRNA point mutations. Although the
skeletal muscle fibres of these patients invariably contain a large
proportion of mutant mtDNAs, mutant mtDNAs are rare or undetectable in
satellite cells cultured from the same muscle biopsy specimens. Since
satellite cells are responsible for muscle fibre regeneration, restoration
of the wild-type mtDNA genotype might be achieved in these patients by
encouraging muscle regeneration. To test this concept, we re-biopsied a
patient with a KSS phenotype and a mtDNA point mutation in the
tRNAleu(CUN)gene and analysed muscle fibres regenerating at the site of the
original muscle biopsy. Regenerating fibres were identified by
morphological criteria and by expression of neural cell adhesion molecule
(NCAM). All such fibers were positive for cytochrome c oxidase (COX)
activity by cytochemistry and essentially homoplasmic for wild-type mtDNA,
while the majority of non-regenerating fibres were COX-negative and
contained predominantly mutant mtDNAs. These results demonstrate that it
may be possible to improve muscle function in similar patients by methods
that promote satellite cell incorporation into existing myofibres.
相似文献