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G H Jones T D Hernandez D A Kendall C A Marsden T W Robbins 《Pharmacology, biochemistry, and behavior》1992,43(1):17-35
This series of experiments compared isolation-reared and socially reared rats for their locomotor activity, behavioural stereotypy, and monoamine function both postmortem and in vivo using intracerebral dialysis. In Experiment 1, isolates showed an altered time course of locomotor activity following d-amphetamine sulphate (AMPH) administration (0.5, 2.0, 3.0, or 5.0 mg/kg, SC). Isolation-reared rats also showed increased sensitivity to the sedative effects of a low dose of apomorphine hydrochloride (0.1 mg/kg) but did not differ from social controls following higher doses of the drug (0.5, 1.5, or 3.0 mg/kg, SC). Isolates showed a decrease in the intensity of apomorphine-induced stereotyped behaviours but no change in stereotypy induced by AMPH. In Experiment 2, isolates had higher postmortem dopamine (DA) concentrations and an altered asymmetry in DA function in the medial prefrontal cortex (PFC) but not in the nucleus accumbens (NAC) or caudate putamen (CPu). Isolated rats also had a lower 5-hydroxyindoleacetic acid (5-HIAA)/5-hydroxytryptamine (5-HT) ratio in the NAC (but not in the PFC or CPu) compared to controls. Experiment 3 used intracerebral dialysis to examine monoamine function in vivo following isolation rearing. Isolates showed greater increases in extracellular DA and greater decreases in DOPAC in response to 2 mg/kg AMPH SC in both the NAC and CPu. There were no apparent differences in the perfusate concentrations of either dopamine (DA), dihydroxyphenylacetic acid (DOPAC), or homovanillic acid (HVA) prior to drug administration. However, consistent with the results of Experiment 2, isolates had a reduced basal perfusate concentration of 5-HIAA from the NAC but not from the CPu. Experiment 4 measured postsynaptic DA function in CPu tissue slices following isolation. Isolation rearing did not affect cAMP accumulation in response to stimulation of D1 DA receptors by DA (0, 2.7, 9, or 30 microM). In addition, isolation rearing did not affect the coupling between D1 and D2 receptors, as measured by the increase in cAMP accumulation with 1 microM 2,3,4,5-tetrahydro-7,8-dihydroxy-1-phenyl-1 H-3-benzazepin (SK&F 38393) and its reduction by 10 microM quinperole hydrochloride (LY 171555). These results are discussed in terms of the possible relationship between these neurochemical findings and the behavioural disturbances following isolation rearing of rats. 相似文献
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AIM: The aim of the study was to explore the information needs of informal carers, and how information from health professionals can become more effective for families caring for people with epilepsy. METHODS: A combined methodology was used, comprising an interview study and a survey. Twelve in-depth interviews with carers were carried out. The questionnaire was developed using the interview data, to which 70 carers responded. RESULTS: Four main themes have been drawn from the study. Carers' of people with epilepsy have a need for improved and more appropriate levels of information giving by health professionals in both primary and secondary care. Carers' perceived self-efficacy expectations in seeking information are positive but they do not always feel listened to. Carers' prefer to receive information in a one-to-one setting but also need information from formats other than leaflets. Carers' perceive barriers to having their information needs met, such as their needs being unrecognised in relation to the person with epilepsy. 相似文献
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Traumatic intratemporal facial nerve injury: management rationale for preservation of function 总被引:6,自引:0,他引:6
N J Coker K A Kendall H A Jenkins B R Alford 《Otolaryngology--head and neck surgery》1987,97(3):262-269
A retrospective review of 29 cases of intratemporal facial nerve injuries included 18 temporal bone fractures, 7 gunshot wounds, and 4 iatrogenic complications. Surgical exploration confirmed involvement of the fallopian canal in the perigeniculate region in 14 longitudinal and 3 transverse or mixed fractures of the petrous pyramid. Gunshot and iatrogenic injuries usually occurred within the tympanic and vertical segments of the facial canal and at the stylomastoid foramen. When hearing is salvageable, the middle fossa approach provides the best access to the perigeniculate region of the facial nerve. In the presence of severe sensorineural hearing loss, the transmastoid-translabyrinthine approach is the most appropriate for total facial nerve exploration. Grade I to III results can be anticipated in timely decompression of lesions caused by edema or intraneural hemorrhage. Undetectable at the time of surgery, stretch and compression injuries with disruption of the endoneural tubules often lead to suboptimal results. Moderate-to-severe dysfunction (Grade IV), with slight weakness and synkinesis, is the outcome to be expected from the use of interpositional grafts. 相似文献
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J. W. Thorpe B. E. Kendall D. G. MacManus W. I. McDonald D. H. Miller 《Neuroradiology》1994,36(7):522-529
Arteriovenous fistulae and malformations (AVFs and AVMs) of the spinal cord are rare, potentially treatable causes of progressive disability. Although a variety of MRI abnormalities has been described, the diagnosis rests on the findings on selective spinal angiography.Collecting T2*-weighted MR images during the passage of a gadolinium bolus gives information about perfusion and blood volume. We carried out dynamic MRI in seven patients with vascular abnormalities (5 dural AVFs, 1 intramedullary AVM, 1 cryptic angioma) and in two patients without an AVM. High resolution T1- and T2-weighted sagittal images of the whole spinal cord were first obtained using a multiarray receiver coil. Sagittal radiofrequency spoilt gradient echo images (GE34/25, flip angle 100) were then obtained during bolus injection of gadolinium-DTPA. Abnormalities were seen in all seven patients with AVFs or AVMs. In the patient with an intramedullary AVM and four of the five with dural AVFs transient signal reduction was seen within the perimedullary venous plexus during passage of the bolus. The findings correlated well with those from selective spinal angiography. We conclude that dynamic MRI offers a useful adjunct to angiography and may localise an arteriovenous shunt when conventional MRI fails to do so. In combination with high-resolution imaging of the entire spinal cord the technique may make myelography redundant; it is simple, well tolerated and can be carried out without significant time penalty. 相似文献
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J Kendall 《ANS. Advances in nursing science》1992,15(2):1-15
Poverty, education, and social problems are inextricably linked to health concerns and cannot be addressed in isolation from each other. Nurses are being challenged to care for clients who are socially, politically, and economically disadvantaged. The model of emancipatory nursing actions is derived from the work of Freire, Habermas, and Katz and presented as a practice model in guiding nurses to begin choosing actions that seek to help people fight back from the depths of their despair, rather than helping people cope and adapt to their oppression. Emancipatory interventions are provided to help nurses launch a new direction toward freeing their clients, rather than herding them through an uncaring and disjointed health and social service system. 相似文献
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