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排序方式: 共有467条查询结果,搜索用时 31 毫秒
1.
W F Rayburn M Z Johnson K L Hoffman S M Donn R M Nelson 《American journal of perinatology》1987,4(2):98-101
A goal for the obstetrician and neonatologist is to screen for risk factors associated with intraventricular hemorrhage (IVH) in the low-birthweight infant. Perinatal events that lead to neonatal metabolic and cardiovascular derangements seem to provoke IVH, and conflicting reports have implicated labor as being contributory. A fetal heart rate (FHR) abnormality during premature labor may be a predictor of subsequent neonatal IVH. For this reason, 5 years of FHR tracings at two university medical centers were reviewed for inborn infants who were delivered after premature labor and weighed less than or equal to 2000 gm. Sixty-four infants developed IVH, but pre-existing labor with a discernible FHR pattern was recorded in only 38 (59%) cases. Interpretations were reassuring in 17 (45%) cases, suspicious in 7 (18%) cases, and ominous in 14 (37%) cases. This proportion of FHR patterns was not significantly different from a matched group of premature infants without IVH during the same period. Interpretations of intrapartum FHR patterns of low-birthweight infants are limited, especially before 30 weeks gestation, and not useful in predicting neonatal IVH. 相似文献
2.
Lorna M Gillespie Simon D White Sunil K Sinha Steven M Donn 《Journal of perinatology》2003,23(3):205-207
OBJECTIVE: We performed a prospective, randomized clinical trial to compare the usefulness of the minute ventilation test (MVT) with clinical judgement in predicting readiness for extubation in preterm newborns with respiratory distress syndrome requiring surfactant therapy and mechanical ventilation. STUDY DESIGN: A total of 42 preterm infants with respiratory distress syndrome were randomized when they reached preselected ventilator settings. The primary outcome measure was the time from study entry to extubation, provided the infant remained extubated for at least 24 hours. RESULTS: Infants evaluated by the MVT were extubated in a significantly shorter period of time (mean of 8 hours) than those evaluated clinically (mean of 36 hours). The extubation failure rate was similar in the two groups. CONCLUSION: The MVT is an easily performed objective measure that can be used to predict readiness for extubation in preterm infants. In this study, it significantly shortened the time for extubation and was not associated with a higher rate of reintubation. 相似文献
3.
Detection of foot-and-mouth disease virus-infected cattle by assessment of antibody response in oropharyngeal fluids. 总被引:2,自引:0,他引:2 下载免费PDF全文
The detection of foot-and-mouth disease virus (FMDV)-persistent carriers among convalescent ruminants is of paramount importance in the aftermath of a field outbreak. To this purpose, FMDV-specific antibody should be investigated first, since virus isolation procedures from such carriers are seriously constrained. The complexity of the overall picture may be compounded by possible emergency vaccinations in the affected areas at the beginning of the outbreak. In this case, it is suggested that mucosal rather than serum antibody be investigated. In fact, we showed that FMDV-infected cattle regularly mount an antibody response in oropharyngeal fluids, in contrast to vaccinated cattle. Antibody could be revealed by neutralization assays and/or an immunoglobulin A (IgA)-specific kinetic enzyme-linked immunosorbent assay (ELISA). Cattle vaccinated once seldom showed a mucosal antibody response, which could be only detected by a total immunoglobulin-specific kinetic ELISA. Very few, if any, cattle showed a mucosal IgA response after repeated vaccinations. Our kinetic, IgA-specific ELISA generally allowed an early detection of FMDV-infected cattle; in particular, it proved to be more sensitive than the usual indirect, antigen-trapping ELISA in experiments on saliva samples. 相似文献
4.
5.
Asphyxia neonatorum 总被引:1,自引:0,他引:1
Various biochemical and structural changes affecting the newborn's wellbeing develop as a result of perinatal asphyxia. Central nervous system abnormalities are frequent complications with high mortality and morbidity. Cardiac compromise may lead to dysrhythmias and cardiogenic shock. Coagulopathy in the form of disseminated intravascular coagulation or massive pulmonary hemorrhage are potentially lethal complications. Necrotizing enterocolitis, acute renal failure, and endocrine problems affecting fluid electrolyte balance are likely to occur. Even the adrenal glands and pancreas are vulnerable to perinatal oxygen deprivation. The best form of management appears to be anticipation, early identification, and prevention of potential obstetrical-neonatal problems. Every effort should be made to carry out effective resuscitation measures on the depressed infant at the time of delivery. 相似文献
6.
Summary Persistent foot-and-mouth disease (FMD) virus infection in vitro has been studied in a chronically infected cloned BHK-21 cell line. Virus growth during serial cell passages was followed by infectivity assay and immunocytochemical staining. Only a small percentage of cells (0.006–6%) was found to harbour virus during persistence. Light and electron microscopy showed the presence of cytoplasmic protuberances (blebs) at the surface of persistently infected cells. The curing of cell cultures was achieved by passaging them in the presence of polyvalent immune serum. The absence of virus in cured cells was confirmed by infectivity assay and immunocytochemistry. This finding, together with the low percentage of infected cells in cultures confirms that persistently infected BHK-21 cells satisfy the definitions of a carrier culture. The characteristics of the in vitro system and its relevance to the study of FMD carrier state in vivo are discussed. 相似文献
7.
Starr PA Rau GM Davis V Marks WJ Ostrem JL Simmons D Lindsey N Turner RS 《Journal of neurophysiology》2005,93(6):3165-3176
Dystonia is a movement disorder defined by sustained muscle contractions, causing twisting and repetitive movements and abnormal postures. To understand the abnormalities in pallidal discharge in dystonia, we have analyzed the spontaneous activity of 453 neurons sampled from the internal or external pallidum (GPi or GPe) of 22 patients with dystonia, 140 neurons from 11 patients with Parkinson's disease (PD), and 157 neurons from two normal non-human primates (NHPs; Macacca mulatta). All recordings were performed without systemic sedation. Mean GPi discharge rate in dystonia was 55.3 +/- 1.3 (SE) Hz. This was significantly lower than in the normal NHPs (82.5 +/-2.5 Hz) and lower than in PD patients (95.2 +/- 2.3 Hz). Mean GPe discharge rate in dystonia (54.0 +/- 1.9 Hz) was lower than in the normal NHPs (69.7 +/- 3.3 Hz) and was indistinguishable from that in PD patients (56.6 +/- 3.5 Hz). Mean GPi discharge rate was inversely correlated with dystonia severity. GPi showed increased oscillatory activity in the 2- to 10-Hz range and increased bursting activity in both dystonia and PD as compared with the normal NHPs. Because the abnormalities in discharge patterns were similar in dystonia compared with PD, we suggest that bursting and oscillatory activity superimposed on a high background discharge rate are associated with parkinsonism, whereas similar bursting and oscillations superimposed on a lower discharge rate are associated with dystonia. Our findings are most consistent with a model of dystonia pathophysiology in which the two striatal cell populations contributing to the direct and indirect intrinsic pathways of the basal ganglia both have increased spontaneous activity. 相似文献
8.
Barton A Lamb R Symmons D Silman A Thomson W Worthington J Donn R 《Genes and immunity》2003,4(7):487-491
The aim of the study was to investigate whether polymorphisms of macrophage migration inhibitory factor (MIF) determine susceptibility to or severity of inflammatory polyarthritis (IP). Genotypes for a single-nucleotide polymorphism (MIF-173*G/C) and a tetranucleotide (CATT)(n) repeat mapping to the promoter region of the MIF gene were compared between UK Caucasian IP cases (n=438) and controls (n=343). Both polymorphisms were also investigated for association with features of disease activity and severity at baseline and by 5 years. The MIF-173*C allele (OR 1.7, 95% CI 1.3-2.4, P=1.8 x 10(-4)) and the CATT(7) allele (OR 1.5, 95% CI 1.0-2.1, P=0.02) were found to be associated with increased susceptibility to IP. Furthermore, presence of the haplotype containing both associated polymorphisms was associated with a three-fold increase risk of developing IP. No association with disease severity or activity either at baseline or by 5 years was detected for either of the promoter polymorphisms studied. In conclusion, MIF is a susceptibility gene for the development of IP. The same alleles previously reported to be associated with susceptibility to juvenile idiopathic arthritis account for the increased risk. The promoter polymorphisms of MIF, investigated in this study, do not influence the severity of disease outcome by 5 years. 相似文献
9.
HIV knowledge and risk factors among men who have sex with men in Ho Chi Minh City,Vietnam 总被引:4,自引:0,他引:4
Colby DJ 《Journal of acquired immune deficiency syndromes (1999)》2003,32(1):80-85
OBJECTIVES: To describe health risk behavior, knowledge, and attitudes about HIV/AIDS and its prevention in men who have sex with men (MSM) in Ho Chi Minh City (HCMC), Vietnam. METHODS: A cross-sectional survey of 219 MSM using a standardized questionnaire. RESULTS: Men who have sex with men were easy to locate and willing to answer detailed questions about their sexual behavior. Self-identified sexual orientation was 67% homosexual, 31% bisexual, and 1.4% heterosexual. High-risk sexual behavior was common. The mean number of sexual partners was 3.3 in the previous month and 14.8 in the previous year. Only 32% used condoms during their last intercourse, and only 40% used a condom when their last intercourse included anal sex. Eighty-one percent reported sex with nonregular male partners, and 22% also had sex with women in the past year. Drug use other than alcohol was rare. Most correctly identified high-risk sexual behavior and body fluids that could transmit HIV; however, only about half knew that someone who appeared healthy could transmit HIV or that there was no cure for AIDS. Self-rated risk for HIV was very low, and fewer than one third believed that homosexuals in Vietnam are at increased risk for HIV. CONCLUSION: Men who have sex with men in HCMC are at high risk for HIV. Knowledge about HIV transmission and prevention could be improved. Education and interventions specifically aimed at MSM are needed, because education targeted at the general population may not reach MSM or influence their behavior. 相似文献
10.
Pickard C Mann C Sinnott P Boggild M Hawkins C Strange RC Hutchinson IV Ollier WE Donn RP 《Journal of neuroimmunology》1999,101(2):207-210
Interleukin-10 (IL10) is an anti-inflammatory cytokine which may modulate disease expression in multiple sclerosis (MS). Three dimorphic polymorphisms within the IL10 promoter region at positions - 1082, -819 and -519 have previously been identified. The - 1082*A allele has been associated with low and the - 1082*G allele with high in vitro IL10 production. We have genotyped 185 Caucasian MS patients and 211 ethnically matched controls for each of these three dimorphisms. MS patients were stratified for severity of disease outcome. No associations were found for any IL10 promoter polymorphisms when the MS cases were compared with controls or with disease outcome with regards to disability. IL10 polymorphism does not appear to be associated with MS or to influence disease progression. 相似文献