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51.
M. J. Peters R. C. Tasker K. M. Kiff R. Yates D. J. Hatch 《Intensive care medicine》1998,24(7):699-705
Objective: Acute hypoxemic respiratory failure (AHRF) is a common reason for emergency pediatric intensive care. An objective assessment
of disease severity from acute physiological parameters would be of value in clinical practice and in the design of clinical
trials. We hypothesised that there was a difference in the best early respiratory indices in those who died compared with
those who survived. Design: A prospective observational study of 118 consecutive AHRF admissions with data analysis incorporating all blood gases. Setting: A pediatric intensive care unit in a national children's hospital. Interventions: None. Results: Mortality was 26/118, 22 % (95 % confidence interval 18–26 %). There were no significant differences in the best alveolar-arterial
oxygen tension gradient (A-aDO2, torr), oxygenation index (OI), ventilation index (VI), or PaO2/FIO2 during the first 2 days of intensive care between the survivors and non-survivors. Only the mean airway pressure (MAP, cm
H2O) used for supportive care was significantly different on days 0 and 1 (p K 0.05) with higher pressure being used in non-survivors. Multiple logistic regression analysis did not identify any gas
exchange or ventilator parameter independently associated with mortality. Rather, all deaths were associated with coincident
pathology or multi-organ system failure, or perceived treatment futility due to pre-existing diagnoses instead of unsupportable
respiratory failure. When using previously published predictors of outcome (VI > 40 and OI > 40; A-aDO2 > 450 for 24 h; A-aDO2 > 470 or MAP > 23; or A-aDO2 > 420) the risk of mortality was overestimated significantly in the current population. Conclusion: The original hypothesis was refuted. It appears that the outcome of AHRF in present day pediatric critical care is principally
related to the severity of associated pathology and now no longer solely to the severity of respiratory failure. Further studies
in larger series are needed to confirm these findings.
Received: 16 December 1997 Accepted: 31 March 1998 相似文献
52.
Infection with a proposed new subspecies of Babesia canis, Babesia canis subsp. presentii, in domestic cats 下载免费PDF全文
Baneth G Kenny MJ Tasker S Anug Y Shkap V Levy A Shaw SE 《Journal of clinical microbiology》2004,42(1):99-105
Parasitemia with a large Babesia species was identified in two domestic cats from Israel. One cat, also coinfected with feline immunodeficiency virus and "Candidatus Mycoplasma haemominutum," had profound icterus and anemia which resolved after therapy, whereas a second cat was an asymptomatic carrier. Amplification and sequencing of the 18S rRNA gene, followed by phylogenetic analyses, indicated that infection was caused by Babesia canis. However, the sequences of the internal transcribed and 5.8S rRNA regions of the ribosomal operon used for subspeciation of B. canis were markedly different from the recognized subspecies of B. canis, which include B. canis vogeli, B. canis canis, and B. canis rossi. Based on phylogenetic comparisons of the 18S rRNA gene, 5.8S, and internal transcribed spacer sequences of the isolates from the cats and on the smaller sizes of the merozoite and trophozoite stages of this parasite, which distinguish it from the subspecies of B. canis present in dogs, we propose to identify the novel feline genotype of B. canis described in the present study as a new subspecies, B. canis subsp. presentii. 相似文献
53.
Séverine Tasker Iain R. Peters Michael J. Day Barbara Willi Regina Hofmann-Lehmann Timothy J. Gruffydd-Jones Chris R. Helps 《Microbial pathogenesis》2009
The aim of the study was to describe blood and tissue copy number distribution during Mycoplasma haemofelis infection and determine if sequestration of organisms in body tissues could explain blood copy number cycling in infected cats. Thirteen domestic–shorthaired cats were used. Blood samples were regularly collected, and at a differing time point post-infection for each cat, tissue samples also collected, for quantitative PCR (qPCR). Absolute haemoplasma copy numbers were calculated for all blood and tissue samples, as well as an estimation of the ratio of tissue haemoplasma copy number to that expected in the tissue if a positive qPCR result arose due to tissue blood supply alone. Cats with high or moderate M. haemofelis blood copy numbers at the time of tissue collection had fewer M. haemofelis copies in most tissues than expected due to the tissue blood supply alone; only splenic and lung tissues consistently contained more M. haemofelis. However tissues collected from cats at a time of very low M. haemofelis blood copy numbers, when putative copy number cycling nadirs were occurring, were usually qPCR negative. Hence no evidence of significant tissue M. haemofelis sequestration was found in this study to explain the copy number cycling reported with this feline haemoplasma species. 相似文献
54.
55.
A Papadopoulou MO Rawashdeh GA Brown AS McNeish IW Booth 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(1):79-83
The short- and long-term effects of an elemental diet in children with acute Crohn's disease were compared with those of prednisolone in historical controls. Clinical remission was induced in 25 of 30 and in 18 of 28 episodes treated for six weeks with an elemental diet and prednisolone. Patients with proximal disease had longer remission after treatment with an elemental diet (p < 0.05) than did patients with colonic disease after treatment with prednisolone (p < 0.01). Disease activity index score improved in both groups compared with the pretreatment scores (p < 0.05). However, the improvement in the elemental diet group was significantly better than in the prednisolone group (p < 0.001). Changes in linear growth were better after treatment with an elemental diet compared with steroids (p < 0.001). Serum albumin and haematocrit concentrations all improved significantly in the children treated with an elemental diet (p < 0.001) but not in those treated with steroids. Thus an elemental diet was better than prednisolone in proximal disease and confirmed improved growth and nutritional status. 相似文献
56.
IJ Griffin TJ Cole KA Duncan AS Hollman MDC Donaldson 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(5):544-549
Recently produced reference curves for various ultrasound dimensions were used to retrospectively assess 67 pelvic ultrasound scans carried out at the initial presentation in girls with sexual precocity. At presentation the group with precocious puberty had significantly increased uterine lengths and ovarian volumes compared with the normal population, and a significantly increased fundal–cervical ratio. Ovarian volume was also significantly increased in thelarche and thelarche variant. The fundal–cervical ratio was significantly increased in thelarche variant. There was considerable overlap between individuals with sexual precocity and normal subjects. The ultrasound findings that best discriminated early or precocious puberty from other forms of sexual precocity were the presence of a midline endometrial echo, and a uterine length above the 97th centile for age. An entirely normal pelvic ultrasound at presentation did not rule out the possibility of precocious puberty. 相似文献
57.
A retrospective chart review and telephone follow-up was conducted on patients who were treated for disseminated coccidioidomycosis involving bones or joints at the Naval Medical Center, San Diego, California from 1993-1999. Thirteen patients were identified, with average follow-up of 36 months. Six patients underwent surgical debridement and systemic medical therapy, and seven patients were treated medically only. All patients improved symptomatically with decreasing complement fixation titers at last follow-up. Five of the six patients treated with combined therapy are currently quiescent. Of those treated medically, four patients are quiescent; three were lost to follow-up. Coccidioidomycosis osteomyelitis remains a rare but difficult disease to treat, with a lifelong risk of recurrence. A combined medical and surgical approach has been shown to be effective, but medical therapy alone with intravenous amphotericin B followed by suppressive azole therapy may be effective in selected patients. 相似文献
58.
59.
Luther JA Daftary SS Boudaba C Gould GC Halmos KC Tasker JG 《Journal of neuroendocrinology》2002,14(12):929-932
Parvocellular neurones of the hypothalamic paraventricular nucleus (PVN) comprise neurosecretory and non-neurosecretory subpopulations. We labelled neurosecretory neurones with intravenous injection of the retrograde tracer, fluoro-gold, and recorded from fluoro-gold-positive and negative PVN parvocellular neurones in hypothalamic slices. Non-neurosecretory parvocellular neurones generated a low-threshold spike (LTS) and robust T-type Ca2+ current, whereas neurosecretory neurones showed no LTS and a small T-current. LTS neurones were located in non-neurosecretory regions of the PVN, and non-LTS neurones were located in neurosecretory regions of the PVN. These findings indicate that neurosecretory and non-neurosecretory subtypes of parvocellular PVN neurones express distinct membrane electrical properties. 相似文献
60.
Otitis media with effusion (glue ear) is the most frequent cause of deafness in children. We investigated the role of gastric juice reflux in this disease. We measured pepsin concentrations in middle ear effusions from children using ELISA and enzyme activity assays. 45 (83%) of 54 effusions contained pepsin/pepsinogen at concentrations of up to 1000-fold greater than those in serum. Our data suggest that reflux of gastric juice could be a major cause of glue ear in children. 相似文献