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1.
A mixed‐method study of effects of a therapeutic play intervention for children on parental anxiety and parents' perceptions of the intervention 下载免费PDF全文
2.
Previous studies indicate that crude oil leads to increased pigmentation and erythema (sunburn) in response to sunlight in exposed individuals. However, no information is currently available concerning whether crude oil exposure might enhance the immunosuppressive effects of solar ultraviolet radiation (UVR) on the skin. In order to address this question, the back skin of shaved, female C3H/HeN mice was exposed to crude oil with or without subsequent treatment with medium-wavelength (UVB) (200 J/m2) or long-wavelength (UVA) (20,000 J/m2) UVR. Immune function was assessed in treated mice by measuring their ability to mount contact hypersensitivity responses to a hapten (2,4-dinitro-1-flyorobenzene, DNGFB) applied to the site of crude oil and UVR treatment as determined by ear swelling upon subsequent challenge. Since Langerhans cells represent an important component of immunity within the skin and because suppression of contact hypersensitivity following UVR treatment is often accompanied by disappearance of Langerhans cells from the epidermis, the impact of these agents on epidermal Langerhans cell density was also analyzed. This was accomplished by enumerating IA-positive cells within the epidermis of treated skin. In these studies, crude oil alone induced inhibition of contact hypersensitivity but had no effect on epidermal Langerhans cells. In contrast, combined treatment with crude oil and UVA led to suppression of contact hypersensitivity, which was accompanied by depletion of epidermal Langerhans cells. 相似文献
3.
Effect of CNTF on low-affinity NGF receptor expression by cultured neurons from different rat brain regions. 总被引:4,自引:0,他引:4
Our previous work indicated that in E14 embryonic rat spinal cord cultures ciliary neuronotrophic factor (CNTF) exerted (1) a survival-promoting effect on motor neurons and on a large population of unidentified neurons, and (2) a regulatory role on the expression of ChAT and low affinity NGF receptor (LNGFR) in a population of small/medium-sized neurons. In the present study, we examined the effect of CNTF on the expression of LNGFR in cultures of different regions from the E18 embryonic rat brain, namely cortex, septum, striatum, mesencephalon, hippocampus, brainstem, and cerebellum. The number of LNGFR-positive neurons (stained with the 192-IgG monoclonal antibody) was determined in untreated cultures and in cultures treated for 6 days (0-6) with human recombinant CNTF. To distinguish between effects on survival and on LNGFR expression, experiments were performed in which CNTF was administered only for the last 48 h of the culture (from days 4-6). LNGFR positive neurons were found in the cultures of all the regions examined. In each one of them, CNTF increased the number of LNGFR-positive neurons by three- to fourfold after 6 days of treatment. In the striatum, septum, mesencephalon, and cerebellum, the effect of CNTF was shown to be on the regulation of LNGFR expression and not on survival. In cultures from the cortex, hippocampus and brainstem, a survival-promoting role of CNTF could be demonstrated. The effect of CNTF was dose dependent, with half-maximal effects (ED50) achieved at 2-4.5 TU/ml for all the brain regions. Maximal effects were reached at 100-250 TU/ml. From these results, we conclude that (1) there exists a wide spectrum of CNTF-responsive neurons in the central nervous system, and (2) CNTF plays an important and widespread role in regulating the expression of the LNGFR in neurons. 相似文献
4.
J. P. Neary T. P. Martin D. C. Reid R. Burnham H. A. Quinney 《European journal of applied physiology》1992,65(1):30-36
Summary The influence of tapering on the metabolic and performance parameters in endurance cyclists was investigated. Cyclists (n = 25) trained 5 days · week–1, 60 min·day–1, at 75–85% maximal oxygen consumption (VO2max) for 8 weeks and were then randomly assigned to a taper group: 4D (4 days;n = 7), 8D (8 days;n = 6), CON (control, 4 days rest;n = 6), NOTAPER (non-taper, continued training;n = 6). Muscle biopsy specimens taken before and after training and tapering were analysed for carnitine palmityltransferase (CPT), citrate synthase, ß-hydroxyacyl CoA dehydrogenase (HOAD), cytochrome oxidase (CYTOX), lactate dehydrogenase, glycogen and protein. Significant increases inVO2max (6%), a 60-min endurance cycle test (34.5%), oxidative enzymes (77–178%), glycogen (35%) and protein (34%) occurred following training. After the taper, HOAD and CPT decreased 25 % (P<0.05) and 26% respectively, in the CON. Post-taper CYTOX values were different (P<0.05) for 4D and 8D compared with CON. Muscle glycogen levels were increased (P<0.05) after tapering in the 4D, 8D and CON, but decreased in NOTAPER. Similarly, power output at ventilation threshold was significantly increased in the 4D (27.4 W) and 8D (27 W) groups, but decreased (22 W) in the NOTAPER. These findings suggest that tapering elicited a physiological adaptation by altering oxidative enzymes and muscle glycogen levels. Such an adaptation may influence endurance cycling during a laboratory performance test. 相似文献
5.
P Iranzo MM Alsina I Martínez-De Pablo S Segura JM Mascaró C Herrero 《Journal of the European Academy of Dermatology and Venereology》2007,21(7):902-907
BACKGROUND: The mainstay of treatment for pemphigus is systemic corticosteroids. Different adjuvants have been used to reduce side-effects of long-term corticotherapy. Gold is an anti-inflammatory drug used in autoimmune diseases, whose use has waned with the advent of new immunosuppressive agents. OBJECTIVE: To study the outcome of the use of intramuscular gold treatment of pemphigus vulgaris refractory to previous therapies. METHODS: Thirteen patients with pemphigus vulgaris who had failed to respond to several prior therapies were treated with aurothiomalate, as a steroid-sparing agent. Patients were monitored to assess disease activity and gold toxicity. RESULTS: Seven patients achieved complete remission. Four patients were able to taper prednisone doses, although pemphigus flared when prednisone was discontinued or reduced. Toxicity was observed in the other two patients. CONCLUSIONS: In 53.4% of the patients, the use of chrysotherapy resulted in the complete clearing of the disease, discontinuation of all systemic therapies and induced a long-term clinical remission. Prednisone doses were able to be reduced in the remaining 46.6%. Any side-effects were reversible with drug discontinuation. Gold therapy showed efficacy as a secondary line treatment in refractory pemphigus vulgaris. 相似文献
6.
Picotamide inhibition of excess in vitro thromboxane B2 release by colorectal mucosa in inflammatory bowel disease. 总被引:1,自引:0,他引:1
Collins CE Benson MJ Burnham WR Rampton DS 《Alimentary pharmacology & therapeutics》1996,10(3):315-320
BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease. 相似文献
7.
D Mahalanabis H Ashraf MM Rahman GJ Fuchs 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(11):1113-1115
One-hundred and six male children aged 6-23 months with a history of acute watery diarrhoea of less than 72 h duration were randomized to receive either folic acid in a dose of 5 mg at 8-h intervals or placebo for 5 d. There were 54 children in the folic acid group and 52 in the placebo group. The admission characteristics were comparable between the two groups. No significant differences were observed in the intake of oral rehydration solution or stool output between the groups. The mean ± SD of total stool output (g kg−1 ) was 532 ± 476 vs 479 ± 354 and the duration (h) of diarrhoea was 108 ± 68 vs 103 ± 53 in the folic acid vs placebo group, respectively. The findings, therefore, should have a positive influence on preventing the inappropriate use of folic acid in acute diarrhoea. 相似文献
8.
9.
Effects of phenytoin, carbamazepine, and clonazepam on cortex- and amygdala-evoked potentials in partially kindled rats 总被引:1,自引:0,他引:1
The kindling technique has been reported to produce a long-lasting enhancement in both the early and late phases of evoked potentials triggered from the kindled focus. It also alters paired-pulse facilitation and depression in the pathways which support these phenomena. The present experiment was designed to determine whether the drugs which antagonize secondary generalization in the kindling model also antagonize kindling-enhanced excitation in the pathways leading out of the focus. Multiple doses of phenytoin, carbamazepine, and clonazepam were therefore tested against single- and double-pulse evoked potentials triggered from the focus in rats that had been subjected to parital kindling from either the amygdala or the cortex. Responses were recorded in monosynaptic sites and in the mesencephalic reticular formation--a polysynaptic site thought to play an important role in secondary generalization. No drug-related effects were found on early evoked potential components, either in the single-pulse or the double-pulse paradigm. Kindling-enhanced late components ("late waves"), however, were clearly and selectively antagonized by clonazepam. 相似文献
10.
W.M. Burnham 《Neuroscience and biobehavioral reviews》1989,13(4):281-288
The GABA (gamma-aminobutyric acid) hypothesis of kindling suggests that the permanent changes caused by the kindling procedure result from a loss of GABA-mediated inhibition. Pharmacological studies have generally supported this hypothesis: GABA-complex antagonists accelerate (or stimulate) kindling, whereas GABA-complex agonists retard (or reverse) it. Assay studies, however, have presented an inconsistent picture. Earlier studies found no GABAergic brain changes after kindling, whereas recent studies have reported postkindling changes in a number of GABA-related parameters. The crucial difference seems to be that earlier studies assayed GABA parameters in "whole tissue," whereas recent studies have concentrated on "synaptic" GABA. As indicated by recent studies, when the "metabolic pool" is excluded, kindled subjects show a variety of persistent abnormalities in the GABA system. These data are generally consistent with the GABA hypothesis of kindling. 相似文献