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101.
Le but de ce travail a été d’évaluer l’efficacité du captopril dans la prévention de l’élévation de la pression artérielle
lors de chirurgie du membre inférieur sous garrot pneumatique en anesthésie balancée. Vingt patients consécutifs ont été inclus
dans cette étude et randomisés en deux groupes. L’un (n = 10), recevant un comprimé de captopril de 50 mg avec la prémédication,
l’autre (n = 10), recevant un comprimé de placebo au même moment. Les différentes variables étudiées (tension artérielle,
fréquence cardiaque) ont été mesurées continuellement. Cette étude a démontré, que le prétraitement par du captopril ne permet
pas de prévenir une augmentation de la pression artérielle pendant la durée de gonflage d’un garrot pneumatique, les moyennes
des tensions artérielles systoliques et diastoliques, à la fin de la période de gonflage du garrot, s’élèvent à 128 /86 et
128/81 dans le groupe captopril et dans le groupe placebo, respectivement. Ce résultat montre que le système rénine-angiotensine
n’intervient pas, ou que peu, dans le phénomène d’augmentation des valeurs tensionnelles induite par un garrot pneumatique.
The aim of this study was to evaluate the effectiveness of captopril for the prevention of the increase of arterial pressure
during orthopaedic surgery requiring the application of lower limb tourniquets with balanced anaesthesia. Twenty consecutive
patients were included in the study and were randomly divided into two groups. The first (n = 10) received 50 mg captopril
orally together with the preanaesthetic medication, the second (n = 10) received a placebo at the same time. The different
variables studied (arterial pressure, heart rale) were continuously measured. This study demonstrated that the pretreatment
with captopril did not prevent an increase of the arterial pressure during the application of a tourniquet. The means of the
systolic and diastolic arterial pressures at the end of the application of the tourniquet were 128/86 and 128/81 in the captopril
group and the placebo group, respectively. This result shows that the renin-angiotensin system does not significantly contribute
to the increase of the arterial pressure induced by a tourniquet. 相似文献
102.
High exposures to organic solvents among graffiti removers 总被引:3,自引:0,他引:3
Helena Anundi Marie-Louise Lind Lennart Friis Nadja Itkes Sven Langworth Christer Edling 《International archives of occupational and environmental health》1993,65(4):247-251
Summary The exposure to organic solvents among 12 graffiti removers was studied. Health effects were also assessed by structured interview and a symptom questionnaire. Blood and urine samples were collected at the end of the day of air sampling. The concentrations of dichloromethane, glycol ethers, trimethylbenzenes and N-methyl-2-pyrrolidinone in the breathing zone of each worker were measured during one working day. The 8-h time-weighted average exposure to dichloromethane ranged from 18 to 1200 mg/m3. The Swedish Permissible Exposure Limit value for dichloromethane is 120 mg/m3. The air concentrations of glycol ethers, trimethylbenzens and N-methyl-2-pyrrolidinone were low or not detectable. No exposure-related deviations in the serum concentrations of creatinine, aspartate transaminase, alanine transaminase, -glutamyl transpeptidase or hyaluronan or the urine concentrations of 1-microglobulin, R2-microglobulin or N-acetyl--glucos-aminidase were found. Irritative symptoms of the eyes and upper respiratory tract were more prevalent than in the general population. This study demonstrates that old knowledge about work harzards is not automatically transferred to new professions. Another aspect is that the public is also exposed as the job is performed during daytime in underground stations. At least for short periods, bystanders may be exposed to high concentrations of organic solvent vapours. People with predisposing conditions, e.g. asthmatics, may risk adverse reactions. 相似文献
103.
Lennart Berglin Peter Gouras Yoahua Sheng Javier Lavid Po-Kang Lin Huiyun Cao Hild Kjeldbye 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1997,235(2):103-110
Background: RPE transplantation offers the possibility of treating certain forms of retinal degeneration. Understanding how to optimize the surgical technique for performing RPE transplantation, especially in primates, is therefore of considerable interest. Methods: Fifteen patch RPE transplants were performed in six monkeys. The transplant sites were examined at follow-up by ophthalmoscopy, biomicroscopy, fluorescein angiography and histology. Foveal and peripheral retinal transplants were compared. Results: Human fetal RPE xenografts can survive without rejection for at least 6 months after transplantation in monkey retina. Such grafts form a basal lamina and make intimate contacts with the outer segments of the host. Both rods and cones retain a normal appearance when in contact with unrejected transplants. Rejection occurred in only 30% (3/10) of the peripheral but in 60% (3/5) of the foveal transplants. Conclusions: Cultured human fetal RPE patch transplants can survive and maintain local photoreceptor integrity for relatively long periods of time in monkey subretinal space without immunosuppression. Rejection, when it occurs, is more frequent near the fovea. 相似文献
104.
105.
107 Swedish subjects, all 20 years old, were studied for the first three years (1990-1992) after they had left the organised dental care for children and adolescents (which is free of charge for all youth through the age of 19). They were registered in four different risk-grouping systems in order to estimate the amount of their future dental care. Three of the systems used registrations from the Public Dental Service records and in the fourth one a dentist made a subjective estimation. The follow-up used dental insurance claims to study performed treatments, courses of treatments and cost. The risk group system that used subjective estimations appeared to be the one that most accurately predicted the actual dental care consumption. Approximately 70% of the subjects received some kind of dental care during the three years. The distribution was not confined to any particular risk group. Ten per cent had received complete dental care annually. Twenty-five per cent went to a private dentist and 75% continued to go to the Public Dental Service. Those who went to a private dentist received substantially more treatment and the annual cost was a little more than twice as much as in the Public Dental Service. 相似文献
106.
Adenosine reduces secondary hyperalgesia in two human models of cutaneous inflammatory pain 总被引:4,自引:0,他引:4
Secondary hyperalgesia is characterized by increased sensitivity to noxious mechanical stimuli in the area surrounding injured skin. The pathophysiological mechanisms involve increased excitability of second-order neurons located in the spinal cord, i.e., central sensitization. The mechanisms behind this phenomenon may be of importance in clinical pain, including neuropathic pain. To study the effects of systemic infusion of the endogenous compound adenosine (ADO) on sensory function, a superficial cutaneous burn injury was induced by the 4-min topical application of mustard oil or by heat (47 degrees C for 7 min) during i.v. ADO infusion (60 microg x kg(-1) x min(-1)). Healthy human subjects (n = 10 for each model) were tested, using a blinded, placebo-controlled procedure. The area of secondary hyperalgesia, as well as tactile and thermal sensory function, was tested using psychophysical methods during and after treatments. ADO significantly reduced the area of secondary hyperalgesia in both models. The maximal reduction compared with placebo was 58% +/- 20% (heat burn) and 39% +/- 13% (mustard oil burn). No other differences in sensory function were observed. The results are interpreted as an ADO-induced modulatory effect on the mechanisms of central sensitization. IMPLICATIONS: We tested the effects of adenosine on the development of increased sensitivity in the skin surrounding a superficial skin injury in humans. A superficial skin bum was induced with a chemical irritant or heat. The results show that adenosine reduces the skin area with increased sensitivity surrounding the injury. 相似文献
107.
Jonsdottir IH Sjöqvist A Lundgren O Thorén P 《Journal of the autonomic nervous system》1999,78(1):18-23
The effects of somatic nerve stimulation on cholera toxin induced secretion was investigated in vivo in anaesthetised rats. Small intestinal secretion was induced with cholera toxin and measured by a gravimetric technique. Afferent stimulation (pulse frequency within train; 100 Hz; train duration: 50 ms; train frequency: 3 Hz) of the sciatic nerve over 30 min significantly reduced the net fluid secretion both during (P < 0.05) and after cessation of the stimulation (P < 0.01). The greatest effect was obtained immediately after the termination of the nerve stimulation when the secretion was reversed to net fluid absorption. The opioid receptor antagonist naloxone (10 mg kg(-1) i.v.) administrated during the stimulation, significantly inhibited the antisecretory effect seen after the stimulation, thus no significant difference was seen between the control period and the periods after cessation of the stimulation. The opioid receptor antagonist naloxone methiodide (10 mg kg(-1) i.v.), which does not cross the blood-brain barrier, partly inhibited the antisecretory effects but not with the same magnitude as naloxone, thus the net fluid secretion was still significantly inhibited after the stimulation (P < 0.05). We conclude that afferent stimulation of the sciatic nerve strongly inhibits the cholera toxin induced secretion in the small intestine. This inhibition involves primarily a central opioid mechanism and to a lesser extent peripheral opioid mechanism. 相似文献
108.
In the Pite? River Valley all persons with memory impairment that interferes with normal life are referred to one hospital department for clinical workup and diagnosis. 619 patients were assessed in the department during the years 1990-1995. Of these, 36.9% had Alzheimer's disease (AD), 30.4% had vascular dementia (VaD), 3.0% had a mixed AD/VaD, 3.2% had frontotemporal dementia and 5.3% had other forms of dementia. Another 7% had memory impairment but no dementia. The overall mean annual incidence rate of clinically relevant dementia was 295/100,000 persons at risk and the mean prevalence rate was 755/100,000 persons. For persons 65 years and older the incidence and prevalence rates were 840 and 2,150/100,000 persons, respectively. This means that annually, approximately 300 persons/100,000 population over the age of 40 need medical attention or social services. 相似文献
109.
Enteropathogenic bacteria in faecal swabs of young children fed on lactic acid-fermented cereal gruels 总被引:2,自引:0,他引:2
The influence of consumption of a lactic acid-fermented cereal gruel togwa with pH < or = 4 on the presence of faecal enteric bacteria such as campylobacter, enterohaemorrhagic Escherichia coli (EHEC:O157), enterotoxigenic Escherichia coli (ETEC), salmonella and shigella was evaluated. Under 5 years old healthy children listed in an ascending order of age were alternatively assigned and given either a lactic-acid fermented cereal gruel togwa (test diet) or an unfermented cereal gruel uji (control diet) once a day for 13 consecutive days. The presence of the enteropathogens was examined in rectal swabs collected from the children at baseline (before feeding session started), on days 7 and 13, and additionally 14 days (follow-up day) after the feeding session had stopped. The swabs were cultured on to different optimal media for respective enteropathogen and confirmed by standard microbiological and serological methods. Campylobacter spp. dominated among the enteropathogens (62% out of total) followed by Salmonella spp., ETEC and Shigella spp. Children with isolated enteropathogens in the togwa group was significantly reduced (P < 0.001) from 27.6% at baseline to 7.8, 8.2 and 12.7% on days 7, 13 and follow-up day, respectively. The effect was more pronounced in those children taking togwa > 6 times during the study period. In the control group, there was a slight decrease from 16.7% at baseline to 11.4% on day 7 and 8.1% on day 13. On the follow-up day, enteropathogens were found in 22.6% of the children, which was significantly higher than in those children taking togwa > 6 times. We conclude, that regular consumption of togwa with pH < or = 4, once a day, three times a week may help to control intestinal colonization with potential diarrhoea-causing pathogens in young children. 相似文献
110.
Accommodative facility training with a long term follow up in a sample of school aged children showing accommodative dysfunction 总被引:3,自引:0,他引:3
Sterner B Abrahamsson M Sjostrom A 《Documenta ophthalmologica. Advances in ophthalmology》1999,99(1):93-101
The primary aim of this project was to study the effect of flip lens-training on the accommodative function in a group of
children with accommodative dysfunction and subjective symptoms such as asthenopia, headache, blurred vision, and avoidance
of near activity. We also wanted to measure the accommodative facility among the children in comparison with a control group.
Another aim of the study was whether flip lens-training increased accommodative facility, and to find out if it also had a
positive effect on their asthenopia and related problems also in long term. Following the training period the accommodative
facility and accommodative function significantly increased and two years after finishing the training period no child had
regained any subjective symptoms and the objective findings were almost the same as at the end of facility training period.
These results suggest that accommodative facility training is an efficient method built on loss of symptoms among children
with accommodative infacility.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献