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91.
Peptides may function as neurotransmitters liberated antidromically by sensory nerve fibres, provoking vascular responses having potential importance in some neurological disorders. Dose-response relaxation curves induced by substance P (SP) and calcitonin gene related peptide (CGRP) have been studied in porcine ophthalmic arteries in vitro. Both peptides induced vasodilation when tested separately (CGRP much greater than SP). Because of the putative interactions between such peptides in this vascular territory, a computerised system was also used for analysing over time the response to a single addition of either 10(-8) M CGRP, 10(-8) M SP or a combination of 10(-8) M SP + 10(-8) M CGRP. SP did not augment the maximum relaxation induced by CGRP alone, but increased significantly the rate of relaxation during the initial phase of the response. The effect induced by the SP+CGRP combination was stronger than the sum of the individual SP and CGRP-induced relaxations during the first 4 min of the response, which suggests a SP-CGRP synergism in this artery. 相似文献
92.
Electrophysiological techniques were used to determine the basal activity of A10 dopamine (DA) neurons in the rat ventral tegmental area after a 10-14 day withdrawal from repeated cocaine treatment (10.0 mg/kg i.p. twice daily for 14 days). The number of spontaneously active A10 DA cells was significantly decreased (42%) in the cocaine-treated rats. This decreased activity may underlie the diminished basal levels of synaptic DA within the nucleus accumbens previously reported in cocaine-withdrawn rats and may account for anhedonia, anergia and cocaine craving reported by withdrawn cocaine addicts. 相似文献
93.
94.
STUDY OBJECTIVE--The aim was to compare the ability of census based social deprivation scores devised by Jarman, Carstairs, and Townsend to predict workload in general practice. DESIGN--This was a prospective study of 140,050 patients registered with general practices over one year from 1 July 1981 (Third National Morbidity Survey). Main outcome measures were workload score for each patient, defined as a weighted sum of consultations at the surgery and consultations elsewhere, excluding preventive procedures. SETTING--25 general practices in England and Wales. MAIN RESULTS--In multivariate analyses the Jarman, Carstairs, and Townsend indices all predicted workload, but the Townsend index was the best predictor, with both housing tenure and car ownership being strong predictors of workload. The overcrowding and geographical mobility variables used in the Jarman index did not predict increased workload. The weighting assigned to children under five by the Jarman index underestimated the additional workload this group generated. CONCLUSIONS--For identifying social pressures on general practice workload the Jarman index is less valid than other census based scores because it fails to include car ownership and housing tenure. A more rational scheme for compensating general practitioners would directly weight the capitation fee for children aged under five years and allocate current deprivation payments according to the Townsend index or a similar score. This would redistribute resources from London to deprived areas in northern England. 相似文献
95.
The heating performance of prototype variable power control units attached to two domestic microwave ovens, 500 W and 700 W, was investigated. The units employed the phase control method where rated voltage was obtained by switching AC supply at a particular angular position on the sinusoidal voltage. In order to create experimental conditions employed in a previous study, Sydney tap water (50 mL) was heated at a 10% power level in the 500 W oven. Water boiled at 10 min in both experiments. However, the precision and control of the heating was greatly improved with addition of the control unit. A disinfecting solution (50 mL) and a tissue fixative (10 mL) were included for experiments with the 700 W oven. A power level of only 1% was sufficient to maintain the temperature of the fixative at low temperatures (30-40 degrees C) where many biological reactions occur. The present results indicate that microwave heating power can be controlled by the variable power control method. This will make temperature control possible through the provision of an electronic feedback loop which links a thermocouple with the power control unit. 相似文献
96.
J M White 《Clinical nurse specialist CNS》1992,6(2):58-63
The purpose of this study was to examine the effects of relaxing music on elevated state anxiety in patients with a confirmed medical diagnosis of acute myocardial infarction. In addition, the relationship between trait anxiety and state anxiety was analyzed. A purposive sample of 40 myocardial infarction patients was randomly assigned to an experimental or control group. Statistically significant reduction in heart rate, respiratory rate, and state anxiety scores were found in the group that listened to relaxing music. A statistically significant positive correlation was found between trait anxiety scores and baseline state anxiety scores. Statistically significant negative correlations were found between trait anxiety scores and the degree of change in posttreatment state anxiety scores when examined as a net change, as well as a percent change. Results suggested that music therapy may be an effective intervention to reduce state anxiety levels in the acute myocardial infarction patient. 相似文献
97.
98.
Linda R White Lars Jacob Stovner Maurice B Vincent Ole Petter Løbben Yara D Fragoso Kristian S Bjerve Ottar Sjaastad 《Cephalalgia : an international journal of headache》1992,12(2):107-110
Our group has previously reported significant changes in the incorporation of precursors into glycerophospholipids, particularly phosphatidylserine, in polymorphonuclear cells obtained from the peripheral blood of cluster headache patients, when compared with controls. The potential of these results led to further work using both the previous methodology and a modified isolation technique to obtain polymorphonuclear cells in as pure a state as possible. Neither the new results obtained using the original technique, nor the results with high purity polymorphonuclear cells from controls and cluster headache patients, confirm the marked changes in precursor uptake into glycerophospholipids originally reported. 相似文献
99.
Donna White Suzanne Moore Stephen Waring Karon Cook Eugene Lai 《Movement disorders》2007,22(7):915-923
To better understand the impact of incident Parkinson's disease (PD) on the Veteran's Health Administration (VHA) and to develop methods applicable to future epidemiological research, we performed a medical record review study at a tertiary referral VHA medical center. Searching the local data base, we identified 782 veterans with diagnostic codes for PD or secondary parkinsonism (SP) between 1998 and 2000. Based on structured medical record review, a movement disorders specialist confirmed diagnoses for incident parkinsonism cases. Among the 782, 191 incident parkinsonism cases were identified (100 PD, 75 SP, and 16 Parkinson's Plus). Incident PD cases were older at diagnosis (74.5 vs. 70.4 yr; P < 0.05) and more likely to be white (81% vs. 62; P < 0.07) than incident SP cases. Diagnostic codes were insufficient to distinguish between incident PD and SP (positive predictive value, 57% and 39%, respectively), and VHA sources failed to identify 21% of confirmed deaths among the incident PD cohort by November 2004. Although the large number of incident cases identified suggests PD is an important cause of disability among elderly VHA users, observed limitations of VHA sources for identifying incident PD cases and determining their vital status should be considered when designing future studies. 相似文献
100.
Angioid streaks were observed in a 31-year-old man with abetalipoproteinemia. Angioid streaks have now been described in hereditary spherocytosis, beta thalassemia, alpha thalassemia, sickle cell anemia, and acanthocytosis secondary to abetalipoproteinemia and hypobetalipoproteinemia. The nature of the association of angioid streaks and structural defects of hemoglobin and the red blood cell is not understood. 相似文献