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51.
G M Simpson K G Yadalam D F Levinson M J Stephanos E S Lo T B Cooper 《Journal of clinical psychopharmacology》1990,10(6):417-421
Fluphenazine decanoate is commonly used as part of maintenance treatment of schizophrenia, but its pharmacokinetics are poorly understood. We administered a single intramuscular dose of fluphenazine decanoate to nine patients and found that plasma fluphenazine level did not decline to 50% of the peak level by day 26 in any of the patients. This means that it has a long half-life measurable in months rather than weeks. 相似文献
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54.
Adenosine receptor-induced cyclic AMP generation and inhibition of 5-hydroxytryptamine release in human platelets. 总被引:1,自引:0,他引:1
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J A Cooper S J Hill S P Alexander P C Rubin E H Horn 《British journal of clinical pharmacology》1995,40(1):43-50
1. We have assessed the effects of adenosine receptor agonists and antagonists on collagen-induced 5-hydroxytryptamine (5-HT) release and cyclic AMP generation in human platelets. 2. 5'-N-ethylcarboxamidoadenosine (NECA) and CGS 21680 elicited accumulations of cyclic AMP with mean EC50 values of 2678 and 980 nM, respectively. The maximal response to CGS 21680 was approximately half that of the response to 10 microM NECA. 3. NECA and CGS 21680 inhibited collagen-induced 5-hydroxytryptamine release with mean EC50 values of 960 and 210 nM, respectively. The maximal response to CGS 21680 was approximately 25% of the response to 10 microM NECA. 4. The A1/A2a-selective adenosine receptor antagonist PD 115,199 was more potent as an inhibitor of NECA-elicited responses than the A1-selective antagonist DPCPX with calculated Ki values of 22-32 nM and > 10 microM, respectively. 5. In the presence of a cyclic AMP phosphodiesterase inhibitor, the effects of CGS 21680 on cyclic AMP accumulation and 5-HT release were enhanced to levels similar to those elicited by 10 microM NECA. In the absence of phosphodiesterase inhibition, CGS 21680 did not antagonise the effects of NECA. Furthermore, endogenous adenosine did not contribute to the effects of CGS 21680 when phosphodiesterase was inhibited. 6. We conclude that an A2a adenosine receptor appears to be involved in the NECA-elicited increases in cyclic AMP levels and inhibition of 5-HT release in human platelets.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
55.
Tony Hope Kathleen M. Tilling Kathy Gedling Janet M. Keene Sandra D. Cooper Christopher G. Fairburn 《International journal of geriatric psychiatry》1994,9(2):149-155
‘Wandering’ is one of the most troublesome of behavioural problems in dementia. The term ‘wandering’ covers many different types of behaviour. We examined the hypothesis that the different types of wandering behaviour seen in dementia from a scale using data collected on 83 elderly subjects suffering from either Alzheimer's disease or multiinfarct dementia. We reject the scaling hypothesis. Our data suggest that there are three main categories of wandering behaviour, and that one of these categories is usefully divided into four subcategories. 相似文献
56.
R L Cooper M L Mole G L Rehnberg J M Goldman W K McElroy J Hein T E Stoker 《Toxicology》1992,71(1-2):69-81
Two experiments were conducted in which the acute effects of inhaled methanol on serum hormones associated with reproductive function in the male rat were evaluated. In the first experiment, rats exposed to methanol (0, 200, 5000 and 10,000 ppm) for 6 h were killed at the end of the exposure period (6 h) or the following morning (24 h). Also, because the process of exposure itself could modify neuroendocrine function, the effect of the handling associated with placing the rat in the exposure chamber was evaluated further by dividing the exposed animals into acclimated (2 weeks of prior handling) and non-acclimated groups. At 6 h, an effect of prior handling was noted in the sham-exposed rats, with serum luteinizing hormone (LH) of the non-acclimated group being greater than that of the acclimated group. Serum LH concentrations were altered by methanol exposure, but the direction of change and the exposure level at which an effect was noted differed between the acclimated and non-acclimated rats. Methanol (5000 ppm) reduced serum LH in the non-acclimated animals, while 10,000 ppm increased LH in the acclimated rats. Follicle stimulating hormone (FSH) and testosterone were unchanged by methanol in rats killed at 6 h. Thus, this experiment did not confirm earlier reports that exposure to 200 ppm for 6 h reduced serum testosterone. At 24 h, an effect of prior handling was still present in the hormonal measures, with serum and interstitial fluid testosterone concentrations being greater in the non-acclimated rats. Also, there was a dose x handling interaction with methanol exposure inducing an increase in serum testosterone in the non-acclimated rats (up to 5000 ppm) and a decrease in the acclimated rats (up to 10,000 ppm). In the second experiment, groups of acclimated and non-acclimated rats were exposed to 0 or 5000 ppm methanol for 1, 2 and 6 h and killed immediately after removal from the chamber. Serum LH, testosterone and FSH values were not different in sham- vs methanol-exposed rats at any time point. As in experiment 1, an effect of prior handling was noted. In general, the concentrations of these hormones and serum prolactin in the non-acclimated rats were greater than those observed for acclimated rats. Methanol exposure resulted in increased prolactin concentrations under both handling conditions.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
57.
Phosphorylation of neurofilament proteins and chromatolysis following transection of rat sciatic nerve 总被引:7,自引:0,他引:7
M E Goldstein H S Cooper J Bruce M J Carden V M Lee W W Schlaepfer 《The Journal of neuroscience》1987,7(5):1586-1594
States of phosphorylation of neurofilament proteins were examined in the perikarya of rat sensory and motor neurons between 3 and 28 d following either a distal transection [6-7 cm from the L4-L5 dorsal root ganglia (DRG)] or a proximal transection (1-2 cm from the L4-L5 DRG) of the sciatic nerve. Paraffin sections of the right (experimental) and left (control) L4 and L5 DRG from animals with unilateral transection of the right distal sciatic nerve were stained immunocytochemically with monoclonal antibodies to phosphorylation-dependent (NF-P), dephosphorylation-dependent (NF-dP), or phosphorylation-independent (NF-ind) epitopes on the largest (NF200), mid-sized (NF150), or smallest (NF68) neurofilament protein subunits. Increased immunoreactivity to NF-P on NF200 and NF150 was detected in experimental DRC at 10 d, peaking by 20 d, and declining to near control levels by 28 d. Conversely, immunoreactivity to NF-dP declined in experimental DRG beginning at 6 d, reaching a maximum decline at 10-16 d, and returning to near control levels by 28 d. Immunocytochemical changes were confirmed with biochemical studies on tissue homogenates that demonstrated an increase of immunoreactivity to NF-P and a decrease of reactivity to NF-dP in the experimental DRG. Changes in immunoreactivities to NF-P and NF-dP were observed only in the perikarya of large neurons and were closely associated with chromatolytic changes in these neurons. Marked enhancement of chromatolysis, as well as the immunoreactivities to NF-P and NF-dP, occurred following a proximal (left side) versus distal (right side) transection in the same animal.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
58.
Physical fitness and all-cause mortality. A prospective study of healthy men and women 总被引:45,自引:9,他引:36
We studied physical fitness and risk of all-cause and cause-specific mortality in 10,224 men and 3120 women who were given a preventive medical examination. Physical fitness was measured by a maximal treadmill exercise test. Average follow-up was slightly more than 8 years, for a total of 110,482 person-years of observation. There were 240 deaths in men and 43 deaths in women. Age-adjusted all-cause mortality rates declined across physical fitness quintiles from 64.0 per 10,000 person-years in the least-fit men to 18.6 per 10,000 person-years in the most-fit men (slope, -4.5). Corresponding values for women were 39.5 per 10,000 person-years to 8.5 per 10,000 person-years (slope, -5.5). These trends remained after statistical adjustment for age, smoking habit, cholesterol level, systolic blood pressure, fasting blood glucose level, parental history of coronary heart disease, and follow-up interval. Lower mortality rates in higher fitness categories also were seen for cardiovascular disease and cancer of combined sites. Attributable risk estimates for all-cause mortality indicated that low physical fitness was an important risk factor in both men and women. Higher levels of physical fitness appear to delay all-cause mortality primarily due to lowered rates of cardiovascular disease and cancer. 相似文献
59.
Barrett's oesophagus: a clinical study of 52 patients 总被引:4,自引:0,他引:4
This paper reports a series of 52 patients with Barrett's (or columnar-lined) oesophagus from one medical unit diagnosed over a six-year period. The commonest associated symptoms were heartburn, regurgitation and dysphagia but 10 patients had no oesophageal symptoms and two had no symptoms at all. Gastrointestinal bleeding (overt or occult) was observed in almost one-third of patients. At diagnosis, 26 patients had oesophagitis, 23 had oesophageal ulceration and 10 had benign oesophageal strictures. An association between oesophageal ulceration and non-steroidal anti-inflammatory drug ingestion was suggested by the data and patients with oesophageal ulceration were significantly older than patients with uncomplicated Barrett's oesophagus. No patient had adenocarcinoma of the oesophagus at diagnosis and neither carcinoma nor dysplasia were seen during a mean period of 16.4 months. However, 17 per cent of patients in the series had malignancies in other sites. Most patients did well on medical treatment and only two were referred for anti-reflux surgery (both for non-healing oesophageal ulcers). Barrett's oesophagus was seen in 10 per cent of patients with gastro-oesophageal reflux at endoscopy. Oesophageal ulceration in patients with Barrett's oesophagus made up 21 per cent of oesophageal ulcers seen and benign oesophageal stricture in patients with Barrett's oesophagus constituted 13 per cent of all benign strictures seen. Barrett's oesophagus is common in our population and despite complications, it can be managed successfully, at least in the short term, by conservative means. 相似文献
60.
The sanctity of the upper lid in lower eyelid reconstruction questioned. A modification of a lid sharing procedure with a long-term follow-up 总被引:1,自引:0,他引:1
Sharing techniques using the upper eyelid to reconstruct the lower one have been criticised for causing distortion of the normal upper lid leading to corneal exposure and possible visual disturbance, and for creating second-rate lids. A modification of previously described tarsoconjunctival flap techniques is described which minimises the known complications of earlier methods. A flap of conjunctiva alone is mobilised from the upper eyelid and covered with a full thickness skin graft. A second minor procedure to divide the flap from its donor site is necessary 2 weeks later. Forty-three patients over a 25-year period have undergone total lower eyelid reconstruction with this modified technique and are reviewed with some illustrative cases. Total or subtotal lower eyelid reconstruction is most commonly performed following tumour resection and only occasionally to correct congenital or traumatic defects. The surgical techniques available still cause controversy (Byrd, 1983). An upper lid sharing technique has been criticised for possibly causing a shortened or distorted normal lid (Mustardé, 1981). A modification of this method is described which has been used for over 25 years and has reduced the morbidity of the procedure, leading to acceptable cosmetic and functional long-term results. 相似文献