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991.
Increased capsaicin cough sensitivity in patients with multiple chemical sensitivity 总被引:1,自引:0,他引:1
Ternesten-Hasséus E Bende M Millqvist E 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2002,44(11):1012-1017
Multiple chemical sensitivity (MCS) is characterized by chemically induced symptoms from multiple organ systems. No consistent physical findings or laboratory abnormalities have been determined for the associated symptoms. Twelve patients with chemically induced airway symptoms, who satisfied Cullen's criteria for MCS, were provoked double-blind, randomized with saline and three increments of inhaled capsaicin. The recordings were compared with those of a control group of healthy individuals. The results found that the patients coughed more than the control subjects at each dose of capsaicin (P < 0.05 for 0.4 mumol/L capsaicin and P < 0.005 for 2 mumol/L and 10 mumol/L). The capsaicin provocation also induced significantly more symptoms in patients with MCS. We conclude that airway sensory reactivity is increased in patients with MCS, a finding which suggests that neurogenic factors may be of importance in this condition. 相似文献
992.
PURPOSE: To investigate the morbidity of postoperative endophthalmitis (POE) following cataract surgery in Sweden in 1998. METHODS: Clinically presumed cases of POE were reported in a prospective survey in which all Swedish ophthalmic surgical units except one had agreed to participate. Data on intraocular cultures and visual outcomes at 3 months after infection were supplied. Surgical cases that became infected were identified in the Swedish National Cataract Register, thereby enabling screening for various putative risk factors. RESULTS: The nationwide incidence of POE amounted to 58 cases out of 54 666 cataract operations, or 0.1% of surgical cases. The predominant aetiology was gram-positive bacteria, which comprised 57% of the material. Acrylic intraocular lenses were found to decrease the risk of POE significantly in comparison to hydrogel and polymethylmethacrylate lenses. CONCLUSIONS: The incidence of POE after cataract surgery in Sweden is similar to that currently reported elsewhere in the developed world. We hope that continued registration of cases of POE in Sweden will shed light on the possible influences of various prophylactic measures and different intraocular lens materials on the development of postoperative infection. 相似文献
993.
The Swedish National Cataract Register (NCR) has been collecting data on cataract extractions in Sweden since 1992. This unique national database now contains data pertaining to more than 400 000 operations, representing 93.4% of all operations performed nationwide during 1992-2000. Clinic participation in the NCR is voluntary. Tests have shown NCR data to be extremely reliable, while the participation of nearly all providers of cataract surgery in Sweden makes the data highly representative of cataract surgery throughout the country. The NCR collects pre- and per-operative data for every cataract extraction performed at participating clinics. Surgical outcome data and data about patients' self-assessed visual function is collected in approximately 10% of cases. Since 1998, all cases of suspected postoperative endophthalmitis have also been reported to the NCR. The rate of surgery has increased from 4.47 to 7.26 per 1000 inhabitants during the period. Female subjects have constituted about 66% of all operated subjects each year and the mean age of patients has slowly increased from 75.2 to 76.1 years. Average pre-operative visual acuity has improved each year. Second eye surgery has increased from 28.5% to 36.8% of all surgeries. Phacoemulsification has reached 98% as type of surgery (in 2000) and 92.7% of all intraocular lenses are foldable. Surgical outcome has improved by achieving a final refraction closer to the target refraction and less surgically induced astigmatism. The positive impact of cataract surgery in very elderly people has been demonstrated, as has the positive effect of second eye surgery, especially in young subjects. The NCR has served to enhance knowledge about trends and results of cataract surgery in Sweden. This review article describes some of the activities carried out and their results. 相似文献
994.
We have developed an Internet-based tool for remote realtime auscultation. The device was based on a commercially available electronic stethoscope and a PC which digitized and transmitted the signals. A voice and video channel were also available. The remote auscultation tool was evaluated between two sites in Sweden separated by a distance of 500 km. A doctor at one of the sites performed cardiac and pulmonary auscultations on patients located at the other site. Four test patients were assisted by a nurse operating the electronic stethoscope. The auscultation sessions were performed with and without video support to assess the importance of visual contact between doctor and patient. Twenty sessions were conducted (excluding technical testing to solve problems with the equipment). Audio quality was sufficient, as judged subjectively by the doctors concerned. Video support improved the doctor s confidence that the stethoscope was being operated properly and greatly simplified the interaction. Moreover, it improved all participants subjective impression of the virtual meeting. Our work demonstrates the feasibility of performing remote auscultation sessions over the Internet. 相似文献
995.
Althin R Lundström M Roos P 《International journal of technology assessment in health care》2002,18(3):635-644
OBJECTIVES: An index approach for measuring the reduction in daily activities of patients suffering from an eye disease associated with progressive visual loss is proposed. The approach is illustrated using data collected from patients with cataract. METHOD: The approach uses recently developed methods based on index theory together with measurements of daily activities. In a simulation based on observations of visual acuity and daily activities in patients with cataract, indexes of changes in benefits were estimated for varying levels of visual acuity. RESULTS: Results show the development of loss in benefits resulting from a progressive deterioration in visual acuity. The results indicate a 40% loss in benefits at low levels of visual acuity, equivalent to a potential increase in benefits of 75% for these individuals following successful treatment. CONCLUSIONS: The proposed index approach may prove useful for measuring reductions in daily activities resulting from the progressive loss of vision in eye disease. The approach has successfully measured the reduction in daily activities in patients with cataract and may be applicable in patients with other eye diseases, including age-related macular degeneration and open-angle glaucoma. 相似文献
996.
Resistance to activated protein C (APC resistance) is the single most important hemostatic defect associated with venous thromboembolic disease. However, little is known about this defect in arterial disease. The aim of this study was thus to investigate the frequency and prognostic importance of APC resistance and its influence on the coagulation system in one type of arterial thrombosis. In this study, 323 patients admitted to hospital because of unstable coronary artery disease, that is, unstable angina pectoris or non-Q-wave myocardial infarction, were investigated and compared with a reference group of apparently healthy individuals. The patients participated in a prospective, multicenter, randomized, and placebo-controlled investigation evaluating the protective value of low molecular weight heparin (dalteparin) in unstable coronary artery disease. The APC ratio was assayed using a modified activated partial thromboplastin time reaction method to measure the response to activated protein C. APC resistance was defined as an APC ratio 2.2. Signs of thrombin activation were measured by prothrombin fragment 1+2 levels. The 7.2% (23/318) occurrence of APC resistance found in patients did not differ from the 5.8% (4/69) level in the reference population (P = 0.16). A significant elevation of the prothrombin fragment 1+2 median level of 2.5 nM (interquartile range, 1.9-3.2 nM) was found in the patients with APC resistance compared with 1.7 nM (interquartile range, 1.2-2.4 nM) in the group with a normal APC ratio (P < 0.01). During the 150-day follow-up period, there was no increased risk of cardiac events in patients with APC resistance. Although accompanied by signs of increased thrombin formation, APC resistance does not seem to be an important risk factor for the development of instability in coronary artery disease. 相似文献
997.
Mats Söderström Melker Lindqvist Jan Hillert Tor-Björn Käll Hans Link 《Journal of neurology》1994,241(6):391-397
Optic neuritis (ON) is a common first manifestation of multiple sclerosis (MS), and examination of patients with ON provides opportunities to study the early clinical stages of MS. This prospective study compares results of brain magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) examinations and HLA-Dw2 phenotyping in 60 consecutive patients with ON. At a median of 17 days after the onset of ON, 69% had oligoclonal IgG bands, and at a median on 79 days after onset, 53% had multiple ( 3) white matter lesions on MRI. Subgroup analyses revealed that MRI abnormalities and oligoclonal IgG bands were equally common in patients examined early or late after the onset of ON. Strong correlations were found between the presence of MRI abnormalities and oligoclonal IgG bands. The HLA-Dw2 phenotype was significantly increased in ON patients compared with controls, but also significantly different from a group of MS patients from the same geographical area. A significant relation was found between Dw2 phenotype and oligoclonal IgG bands. During a mean follow-up time of about 2 years, the diagnosis in 17 of the patients changed to clinically definite MS. Initially, 16 of them had oligoclonal IgG bands and 12 had three or more MRI lesions. Both MRI and CSF studies are important diagnostic tools in the work-up of ON patients. 相似文献
998.
Mats E. Johansson Marianne Brundin Lisbeth Adamson Lena Grillner Margareta Landqvist rke Thrner Benita Zweygberg Wirgart 《Journal of medical virology》1989,28(2):63-68
The authors isolated during 1987 seven adenovirus type 31 (Ad31) within a 9-month period. The isolates were obtained from urine, throat, and feces, implying a systemic spread of the infection. Most patients displayed gastrointestinal symptoms, but some had respiratory symptoms and fever. All of the strains differed by restriction endonuclease analysis from the prototype strain (1315) by an additional Bgl II restriction site. Ad31 isolates 1-6 could be divided into two groups by the enzymes Bam HI, Msp I, and Xho I. Each enzyme gave rise to the same group distribution: isolates 1-3 and 4-6, respectively. Digestion with Bst EII, Hind III, Kpn I, and Sma I resulted in identical patterns for isolates 1-6. Isolate 7, however, demonstrated a DNA deletion of approximately 0.8 kbp, but it was otherwise identical to isolates 4-6. In conclusion, two separate genome types of Ad31 were isolated, one of which included a DNA deletion mutant. The increased isolation rate may reflect an epidemiological situation, as the same isolation procedure had been used both before and after this period. 相似文献
999.
The urinary excretion in guinea pigs of the major urinary metabolite of prostaglandins E1 and E2, viz 5β,7α-dihydroxy-11-ketotetranor-prostanoic acid, was increased 5–9 fold following scalding injury. Lipid extracts of homogenates of scalded guinea pig skin contained 20–40 times more smooth muscle stimulating activity than did extracts of non-scalded skin. Prostaglandins (mainly PGE2 and PGF2α) were responsible for about 80% of this activity. 相似文献
1000.
We investigated the effect of between and within trial changes in pitch and loudness on the electrodermal orienting reaction (OR), perceptions of movement, and their interaction. First, following 20 habituation trials (6-s, 80dB, 1000 Hz), four groups of 10 subjects experienced either an increase or a between-trial decrease in pitch (2000 or 500 Hz) or loudness (90 or 70 dB) on the 21st trial. Second, four additional groups of 20 subjects heard 20 tones that, within each 6-s trial, either increased or decreased in pitch (500 to 2000 or 2000 to 500 Hz) or loudness (70 to 90 or 90 to 70 dB). During a dishabituation phase each group was split into halves having a nonchanging tone either increasing or decreasing relative to mean pitch or loudness. After each session subjects rated whether they perceived tones as approaching, retreating, or motionless. Compared with groups experiencing constant stimuli, groups presented tones changing within trials had greater skin conductance responses that habituated slower irrespective of direction of change or its perception. During dishabituation a similar number of subjects dishabituated to a stimulus increase as compared to a decrease irrespective of whether the change was in pitch or loudness. Perceptions of movement treated as an independent variable did not predict habituation or dishabituation of the OR. The results generally support Sokolov, and are discussed in relation to hypotheses presented by Sokolov, O'Gorman, and Bernstein. 相似文献