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排序方式: 共有1115条查询结果,搜索用时 15 毫秒
1.
Martin F. Ward Angie Titchen Clare Morrell Brendan McCormack Alison Kitson 《Journal of clinical nursing》1998,7(1):29-36
? The paper describes a multiproject practice development programme undertaken over a period of 1 year. ? The background and development of the programme are outlined, whilst attention is paid to the innovatory nature of the work, particularly the use of inductive, deductive and integrated approaches to both change implementation and project supervision. ? The programme was monitored throughout using different data sources and the paper uses evaluative material retrospectively to provide answers to organizational and professional difficulties which arose during the course of the programme. ? The authors conclude that the use of combinations of different models for practice development has potential, but requires careful supervision. ? They also recommend that those involved in practice development are made fully aware of its local or micropolitics, and develop strategies to deal with change before it occurs, not after it has taken place. 相似文献
2.
M. S. Avidan N. Jones R. Ing M. Khoosal C. Lundgren & D. F. Morrell 《Anaesthesia》1997,52(11):1073-1076
We sought to determine whether the forced air convection warmers (nine Bair Huggers, Augustine Medical, and one Warm Touch, Mallinkrodt Medical) used in our operating theatres could be a source of microbial pathogens. Agar plates were placed directly in the air stream of the warmers. Four of these grew potentially pathogenic organisms. When the warmers were set to blow through perforated blankets, no growth occurred. Three of the warmers were swabbed and sites of colonisation were found in their hoses. After fixing a microbial filter to the end of the hose, organisms were no longer detectable. We conclude that these warming devices are a potential source of nosocomial infection. They should only be used in conjunction with perforated blankets, should have their microbial filters changed regularly and their hoses sterilised. The inclusion of a microbial filter into the nozzle of the hose could be incorporated into the design of the warmer. 相似文献
3.
4.
Multiple subpial transection: a new approach to the surgical treatment of focal epilepsy 总被引:50,自引:0,他引:50
A new operative approach has been designed for the relief of medically intractable focal epilepsy. It is intended particularly to be used in those cases where the epileptogenic lesion lies in "unresectable" cortex; that is, those cerebral regions subserving speech, memory, and primary motor and sensory function. The procedure is based upon experimental evidence indicating 1) that epileptogenic discharge requires substantial side-to-side or horizontal interaction of cortical neurons, and 2) that the major functional properties of cortical tissue depend upon the vertical fiber connections of the columnar units. The technique requires severing of tangential intracortical fibers while preserving the vertical fiber connections of both incoming and outgoing nerve pathways and of the penetrating blood vessels which also have a vertical orientation. In this study, the effect of multiple subpial transection was assessed on both function and seizure control. The effect on function was reviewed in 32 cases; only 20 cases were evaluated with respect to seizure control, since a follow-up period of 5 years or more (5 to 22 years) is required before conclusions can be drawn. Multiple subpial transection was applied to the precentral gyrus in 16 cases, the postcentral gyrus in six, Broca's area in five, and Wernicke's area in five. With respect to function, the major finding was that none of the 32 patients has suffered a clinically significant behavioral deficit (although subtle deficits could be detected by careful neurological examination). Complete control of seizures has been obtained in 11 (55%) of the 20 cases evaluated. Nine patients developed recurrent seizures consequent to progressive disease unsuspected before operation (Rasmussen's encephalitis in five, tumor in three, and subacute sclerosing panencephalitis in one). In none of these cases, however, did the recurrent seizures arise in the transected zone. Thus, the results indicate that multiple subpial transection is about as effective as standard excisional therapy, and can be successfully employed when epileptogenic lesions encroach upon cortical territories, the removal of which would be functionally incapacitating. 相似文献
5.
Pete Kaiser Tuang Yeow Poh Lisa Rothwell Stuart Avery Sucharitha Balu Uday S Pathania Simon Hughes Marianne Goodchild Shaun Morrell Michael Watson Nat Bumstead Jim Kaufman John R Young 《Journal of interferon & cytokine research》2005,25(8):467-484
As most mechanisms of adaptive immunity evolved during the divergence of vertebrates, the immune systems of extant vertebrates represent different successful variations on the themes initiated in their earliest common ancestors. The genes involved in elaborating these mechanisms have been subject to exceptional selective pressures in an arms race with highly adaptable pathogens, resulting in highly divergent sequences of orthologous genes and the gain and loss of members of gene families as different species find different solutions to the challenge of infection. Consequently, it has been difficult to transfer to the chicken detailed knowledge of the molecular mechanisms of the mammalian immune system and, thus, to enhance the already significant contribution of chickens toward understanding the evolution of immunity. The availability of the chicken genome sequence provides the opportunity to resolve outstanding questions concerning which molecular components of the immune system are shared between mammals and birds and which represent their unique evolutionary solutions. We have integrated genome data with existing knowledge to make a new comparative census of members of cytokine and chemokine gene families, distinguishing the core set of molecules likely to be common to all higher vertebrates from those particular to these 300 million-year-old lineages. Some differences can be explained by the different architectures of the mammalian and avian immune systems. Chickens lack lymph nodes and also the genes for the lymphotoxins and lymphotoxin receptors. The lack of functional eosinophils correlates with the absence of the eotaxin genes and our previously reported observation that interleukin- 5 (IL-5) is a pseudogene. To summarize, in the chicken genome, we can identify the genes for 23 ILs, 8 type I interferons (IFNs), IFN-gamma, 1 colony-stimulating factor (GM-CSF), 2 of the 3 known transforming growth factors (TGFs), 24 chemokines (1 XCL, 14 CCL, 8 CXCL, and 1 CX3CL), and 10 tumor necrosis factor superfamily (TNFSF) members. Receptor genes present in the genome suggest the likely presence of 2 other ILs, 1 other CSF, and 2 other TNFSF members. 相似文献
6.
7.
The effect of sleep on reflex genioglossus muscle activation by stimuli of negative airway pressure in humans. 总被引:3,自引:4,他引:3
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The present study was designed to determine the effect of sleep on reflex pharyngeal dilator muscle activation by stimuli of negative airway pressure in human subjects. Intra-oral bipolar surface electrodes were used to record genioglossus electromyogram (EMG) responses to 500 ms duration pressure stimuli of 0 and -25 cmH2O applied, via a face-mask, in four normal subjects. Stimuli were applied during early inspiration in wakefulness and in periods of non-rapid-eye-movement (non-REM) sleep, defined by electroencephalographic (EEG) criteria. The rectified and integrated EMG responses to repeated interventions were bin averaged for the 0 and -25 cmH2O stimuli applied in wakefulness and sleep. Response latency was defined as the time when the EMG activity significantly increased above prestimulus levels. Response magnitude was quantified as the in ratio of the EMG activity for an 80 ms post-stimulus period to an 80 ms prestimulus period; data from after the subject's voluntary reaction time for tongue protrusion (range, 150-230 ms) were not analysed. Application of the -25 cmH2O stimuli caused genioglossus muscle activation in wakefulness and sleep, but in all subjects response magnitude was reduced in sleep (mean decrease, 61%; range, 52-82%; P = 0.011, Student's paired t test). In addition, response latency was increased in sleep in each subject (mean latency awake, 38 ms; range, 30-50 ms; mean latency asleep, 75 ms; range, 40-110 ms; P = 0.072, Student's paired t test). Application of the -25 cmH2O stimuli caused arousal from sleep on 90% occasions, but in all cases the reflex genioglossus muscle responses (maximum latency, 110 ms) always proceeded any sign of EEG arousal (mean time to arousal, 643 ms; range, 424-760 ms). These results show that non-REM sleep attenuates reflex genioglossus muscle activation by stimuli of negative airway pressure. Attenuation of this reflex by sleep may impair the ability of the upper airway to defend itself from suction collapse by negative pressures generated during inspiration; this may have implications for the pathogenesis of obstructive sleep apnoea. 相似文献
8.
P E Klapper G M Cleator D Prinja-Wilks D J Morris G Morrell 《Journal of virological methods》1990,27(3):327-339
An immunoradiometric assay (radio-immunosorbent test; RIST) for the detection of IgG antibodies to human herpesvirus 4 [human cytomegalovirus (CMV)] has been developed. The technique utilizes CMV antigen passively adsorbed to a polyvinyl microtitration plate and a radiolabelled murine monoclonal anti-human IgG antibody to detect binding of human antibody to the 'solid phase' reagent. The assay was optimized, and its specificity confirmed by testing paired acute and convalescent sera from patients with acute CMV or other human herpesvirus infections. To determine the assay's sensitivity 1433 blood donor sera were examined. The RIST was more sensitive than a standard complement fixation (CFT), in that 53% of these sera were positive by RIST and 48% positive by CFT. There were 1303 concordant results, 88 sera positive only by RIST and 19 sera were only positive by CFT. These discrepant results remained after an attempt to exclude false positive reactivity; their significance is discussed. Use of a monoclonal anti-human IgG antibody in the RIST reduced non-specific binding to the control uninfected cell antigen such that blood donor sera could be tested in the assay using only a CMV antigen without generating an unacceptable false positive rate. 相似文献
9.
A family study of bipolar I disorder in adolescence. Early onset of symptoms linked to increased familial loading and lithium resistance 总被引:7,自引:0,他引:7
M Strober W Morrell J Burroughs C Lampert H Danforth R Freeman 《Journal of affective disorders》1988,15(3):255-268
Lifetime rates of psychiatric illness were compared in relatives of adolescent probands with bipolar I disorder and in relatives of age-matched schizophrenic controls. Familial aggregation of major affective disorders was observed in bipolar probands, the rate of bipolar I disorder greatly exceeding that reported in relatives of adult bipolar probands. Adolescent probands with childhood onset of psychiatric disturbance were distinguished from probands who had no premorbid childhood psychiatric abnormality in two ways: (1) significantly increased aggregation of bipolar I disorder in first-degree relatives; and (2) poorer antimanic response to lithium carbonate. These data underscore important heterogeneity in adolescent-onset bipolar disorder. 相似文献
10.
Vaughan JR; Farrer MJ; Wszolek ZK; Gasser T; Durr A; Agid Y; Bonifati V; DeMichele G; Volpe G; Lincoln S; Breteler M; Meco G; Brice A; Marsden CD; Hardy J; Wood NW 《Human molecular genetics》1998,7(4):751-753
A mutation in exon 4 of the human alpha-synuclein gene was reported
recently in four families with autosomal dominant Parkinson's disease (PD).
In order to examine whether mutations in this exon or elsewhere in the gene
are common in familial PD, all seven exons of the alpha- synuclein gene
were amplified by PCR from index cases of 30 European and American
Caucasian kindreds affected with autosomal dominant PD. Each product was
sequenced directly and examined for mutations in the open reading frame. No
mutations were found in any of the samples examined. We conclude that the
A53T change described in the alpha- synuclein gene is a rare cause of PD or
may even be a rare variant. Mutations in the regulatory or intronic regions
of the gene were not excluded by this study.
相似文献