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21.
OBJECTIVES: Non-painful sensory phenomena or "phantom" sensations are common after spinal cord injury. However, the physiological mechanisms responsible for these sensations are poorly understood. The aim of this study, therefore, was to document in a prospective fashion the time course, prevalence, and features of non-painful sensory phenomena after spinal cord injury, and to determine whether there was a relation between the presence of these sensations and completeness, level of injury, and type of spinal cord injury. METHODS: Patients admitted to an acute spinal injuries unit were interviewed after admission and at several time points over a 2 year period to determine the presence and characteristics of non-painful sensations. Sensations were divided into simple and complex, with complex referring to sensations that incorporated a sensation of volume, length, posture, or movement. RESULTS: The present study showed that the large majority (90%) of patients experience either type of sensation and most complex sensations (60%) are first experienced within 24 hours after the injury. Complex sensations were more common in those patients who had complete spinal cord injuries. The presence of either type of sensation did not seem to be related to the level of injury or the type of injury (cord syndrome). A relatively small proportion (22%) of patients reported that the postural sensations were related to their position at the time of injury and sensations were more commonly related to a familiar, comfortable, or often used position before the spinal cord injury. CONCLUSION: Complex sensations such as postural illusions seem to be due to functional changes in the CNS that may occur almost immediately after spinal cord injury. These sensations may be related to a strong sensory memory "imprint" that has been established before injury. 相似文献
22.
23.
Warrington SJ Turner P Mant TG Morrison P Haywood G Glover V Goodwi BL Sandler M John-Smith PS McClelland GR 《Journal of psychopharmacology (Oxford, England)》1991,5(1):82-91
The clinical pharmacology of the new reversible monoamine oxidase (MAO) inhibitor, moclobemide, was examined in three separate studies in healthy male volunteers. In a single oral dose study, moclobemide (25-150 mg) was rapidly absorbed from the gastrointestinal tract and had a relatively short plasma half-life (mean 1.3 h after 150 mg). A decrease in the plasma concentrations of the noradrenaline metabolite 4- hydroxy-3-methoxyphenylglycol (HMPG), however, indicated a longer time to peak pharmacodynamic effect and longer duration of activity. Assay of platelet MAO activity did not reveal any evidence of irreversible inhibition of the B form of the isoenzyme. Single oral doses of moclobemide (150 and 300 mg) significantly lowered the threshold to the cardiovascular effects ('cheese reaction') of intravenous tyramine. However, after repeated administration of 100 mg three times daily for over 2 weeks, moclobemide caused significantly less potentiation than did phenelzine (15 mg three times per day) on the cardiovascular effects of oral tyramine, a clinically more relevant model. The MAO-B inhibitor, selegiline (5 mg once daily), also lowered the oral tyramine threshold significantly. Moclobemide was generally well tolerated by these healthy volunteers. 相似文献
24.
Higher fat and energy intakes confer a survival advantage in cystic fibrosis (CF). There is a need to develop effective nutrition programmes that ensure optimal energy intake in CF.
A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.
Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.
Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item. 相似文献
Methodology:
A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.
Results:
Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.
Conclusion:
Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item. 相似文献
25.
OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease. 相似文献
26.
27.
Predicting readmission to hospital with asthma 总被引:2,自引:0,他引:2
D RAYMOND RL HENRY N HIGGINBOTHAM & M COORY 《Journal of paediatrics and child health》1998,34(6):534-538
28.
Oestrogen-regulated genes in breast cancer: association of pLIV1 with response to endocrine therapy.
R. A. McClelland D. L. Manning J. M. Gee P. Willsher J. F. Robertson I. O. Ellis R. W. Blamey R. I. Nicholson 《British journal of cancer》1998,77(10):1653-1656
Northern hybridization analyses of the oestrogen-inducible mRNAs pLIV1 and pS2 were compared with oestrogen receptor (ER) immunocytochemistry assessments in 40 untreated primary or early recurrent breast tumours. Significant associations were observed between pLIV1/ER (P < 0.03), pS2/ER (P < 0.001) and pLIV1/pS2 (P < 0.04) status. After disease recurrence, patients were treated with assessable courses of endocrine therapies. Positive pLIV1, pS2 and ER statuses in primary disease were consequently found to be predictive of endocrine responsiveness in the secondary lesions (P < 0.03, P < 0.02, P < 0.005 respectively). However, despite these associations, a number of pLIV1- and/or pS2-positive tumours failed to respond to therapy. 相似文献
29.
Bolontrade MF; Stern MC; Binder RL; Zenklusen JC; Gimenez-Conti IB; Conti CJ 《Carcinogenesis》1998,19(12):2107-2113
In this study we have analyzed the vascular response induced in the two-
stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not
been explored in this model, which is the paradigm of multistage
carcinogenesis and a model for neoplastic lesions derived from exophytic
premalignant lesions (e.g. colon carcinoma, bladder papilloma). We
investigated if angiogenesis is involved in the formation of papillomas and
in the progression from papilloma to carcinoma. To this end we analyzed the
vasculature of normal and hyperplastic skin, focal epidermal hyperplasias
that are precursors of papillomas, papillomas at different stages and
squamous cell carcinomas. We also analyzed the vascularization of
papillomas induced in two strains of mice that differ in their
susceptibility to malignant progression. We show here that angiogenesis is
turned on in the earliest stages of papilloma formation. In late stages,
regardless of state of progression, the predominant response is an increase
in the size of blood vessels. Thus, in the SENCAR mouse model,
representative of exophytic tumors, the angiogenesis switch is a very early
event, probably mechanistically related to the development of the primarily
exophytic lesions. Therefore, the density of blood vessels cannot be used
as a predictor of malignant progression in this model.
相似文献
30.
The Basis of Hyperspecificity in Autism: A Preliminary Suggestion Based on Properties of Neural Nets
McClelland JL 《Journal of autism and developmental disorders》2000,30(5):497-502
This article reviews a few key ideas about the representation of information in neural networks and uses these ideas to address one aspect of autism, namely, the apparent hyperspecificity that is often seen in autistic children's application of previously acquired information. Hyperspecificity is seen as reflecting a possible feature of the neural codes used to represent concepts in the autistic brain. 相似文献