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991.
992.
BACKGROUND: Prospective assessment of non-reactivity to local anaesthetics is a frequent reason for allergy consultation. OBJECTIVES: To investigate the clinical profiles of subjects referred for allergy evaluation; to prospectively reduce the frequency of evaluation by assessing the persistence, during clinical use, of non-reactivity to contaminant/additive-free mepivacaine; and to determine the usefulness of a diagnostic protocol involving patch testing. METHODS: In a prospective study, 198 consecutive patients underwent collection of clinical data, skin prick tests and patch tests using allergens/antigens relevant for the investigation, and an intradermal/subcutaneous challenge procedure using contaminant/additive-free mepivacaine, as appropriate. Patients were followed up for 3 years for assessment of non-reactivity persistence using the same diagnostic protocol. RESULTS: Only one-third of the patients had a history of previous adverse local anaesthetic reactions. Absence of sensitization to contaminant/additive-free mepivacaine persisted in all subjects completing the follow-up. Controlled challenge with mepivacaine was negative in 196 patients with both negative specific skin prick tests and patch tests but it was eventful in two subjects with positive specific patch tests. A few subjects displayed positive skin prick tests and/or patch tests for latex and/or additives. CONCLUSIONS: A few patients had a relevant history for potential local anaesthetic-induced adverse reactions. Upon assessment of absence of sensitization and reactivity, contaminant/additive-free mepivacaine could safely be given for as long as 3 years. The patch testing was shown to be useful and safe for prediction of challenge outcomes. True allergic reactions to contaminant/additive-free mepivacaine were not observed in our patient series.  相似文献   
993.
994.
995.
The diagnosis of rheumatoid arthritis (RA) must be made early, because prompt initiation of treatments tailored to disease activity is crucial to improve structural and functional outcomes. Anti-citrullinated peptide antibodies (ACPAs) are well-established diagnostic markers for RA and should be included in the classification criteria. Here, we describe the main tests for detecting ACPAs and we underline the diagnostic and prognostic usefulness of ACPAs in patients with RA. The presence of ACPAs predicts poorer functional and structural outcomes, and ACPA titers respond to some of the medications used in RA. Therefore, ACPA titers should be determined at regular intervals throughout follow-up.  相似文献   
996.
Aims To determine if impulsivity and socio‐economic status (SES) interact to influence gambling onset in youth. Design Longitudinal study of grade 7 students followed for 8 years. Setting Montréal, Canada. Participants A total of 628 adult students aged 12.6 years on average at cohort inception. Measurements Impulsivity and SES (parent education, area deprivation) were collected during secondary school. Age of gambling onset was collected retrospectively when participants were aged 20.3 years. Cox proportional hazards regression was used to model the association between time to first report of gambling and interaction terms for each of impulsivity and parent education, and impulsivity and area deprivation accounting for sex and ethnicity. Findings Median (interquartile range) age of gambling onset was 17.0 (4.0) years. Impulsivity independently increased the risk of gambling onset among participants with no university‐educated parent [hazard ratio (HR) 1.3; 95% confidence interval 1.1–1.5] and those living in highly deprived areas (HR 1.7; 1.5–2.0). Impulsivity was not associated with gambling onset among high SES youth. Among participants with high impulsivity, risks were elevated for those with no university‐educated parent relative to one or more university‐educated parent (HR 1.7; 1.1–2.7), and for participants living in deprived relative to advantaged areas (HR 5.0; 2.6–9.6). SES was not associated with gambling onset among participants with low impulsivity. Conclusions Impulsivity is a risk factor for gambling onset among low but not high SES youth, and low SES influences gambling onset primarily among impulsive youth. Gambling prevention programmes may need to consider potential interaction between impulsivity and SES.  相似文献   
997.
Thrombolytic stroke therapy with tissue plasminogen activator (tPA) remains complicated by serious risks of cerebral hemorrhage and brain injury. In this study, a novel model of tPA-induced hemorrhage was used in spontaneously hypertensive rats to examine the correlates of hemorrhage, and test methods of reducing hemorrhage and brain injury. Homologous blood clot emboli were used to occlude the middle cerebral artery in spontaneously hypertensive rats, and delayed administration of tPA (6 hours postischemia) resulted in high rates of cerebral hemorrhage 24 hours later. Compared with untreated rats, tPA significantly increased hemorrhage volumes by almost 85%. Concomitantly, infarction and neurological deficits were worsened by tPA. A parallel experiment in normotensive Wistar-Kyoto rats showed markedly reduced rates of hemorrhage, and tPA did not significantly increase hemorrhage volumes. To examine whether tPA-induced hemorrhage was caused by the delayed onset of reperfusion per se, another group of spontaneously hypertensive rats was subjected to focal ischemia using a mechanical method of arterial occlusion. Delayed (6 hours) reperfusion via mechanical means did not induce hemorrhage. However, administration of tPA plus delayed mechanical reperfusion significantly increased hemorrhage volumes. Since reperfusion injury was implicated, a final experiment compared outcomes in spontaneously hypertensive rats treated with tPA plus the free radical spin trap alpha-phenyl tert butyl nitrone (alpha-PBN) versus tPA alone. tPA-induced hemorrhage volumes were reduced by 40% with alpha-PBN, and infarction and neurological deficits were also decreased. These results indicate that (1) blood pressure is an important correlate of tPA-induced hemorrhage, (2) tPA interacts negatively with reperfusion injury to promote hemorrhage, and (3) combination therapies with anti-free radical treatments may reduce the severity of tPA-induced hemorrhage and brain injury after cerebral ischemia.  相似文献   
998.
999.
Here we report median and common peroneal nerve SEPs in a patient with tabes dorsalis. SEPs were within normal limits following median nerve stimulation, but of prolonged latency for common peroneal nerve. This was in keeping with clinical findings of posterior column involvement confined to the lumbosacral tract and with pathological features of tabetic neurosyphilis.
Sommario Gli autori riportano le caratteristiche dei potenziali evocati somatosensoriali del nervo mediano e peroneo comune in un paziente affetto da tabe dorsale. I potenziali evocati somatosensoriali sono risultati nei limiti della norma stimolando il nervo mediano ma di latenza aumentata per il nervo peroneo comune. Ciò risultava in accordo sia con le caratteristiche cliniche di segni di interessamento dei cordoni posteriori limitato al tratto lombosacrale che con le caratteristiche anatomopatologiche della neurosifilide.
  相似文献   
1000.
Postoperative cholangitis is a frequent and unpredictable complication of unknown etiology following bile duct reconstruction (BDR), particularly for biliary atresia. This study was undertaken to correlate the growth of bacteria in the hepaticojejunostomy with that in the liver after BDR. Quantitative bacterial culture was done on the specimens taken from the liver and from the hepaticojejunostomy at 1 week (group 1, n = 7), 1 month (group 2, n = 7), and 2 months (group 3, n = 7) following BDR with Roux-en-Y hepaticojejunostomy in piglets after 2 weeks of common bile duct ligation. The histological examination of the liver and the hepaticojejunostomy, as well as serial monitoring of hemogram and liver function tests, were performed to correlate the findings with the bacterial concentration of the liver and the hepaticojejunostomy following BDR. The bacterial concentration of the hepaticojejunostomy, expressed as log10 colony-forming units per gram (log10 CFU/g) of the hepaticojejunostomy, showed a progressive decrease from 8.38 ± 1.36 in group 1, 7.07 ± 2.54 in group 2, to 3.56 ± 1.31 in group 3 (p = 0.001). The log10 CFU/g of the liver also showed a progressive decrease from 5.02 ± 1.59 in group 1, 3.16 ± 1.56 in group 2, to 2.19 ± 1.09 in group 3 (p = 0.006). There was a significant positive correlation of the log10 CFU/g of the liver (n = 21) with that of the hepaticojejunostomy (n = 21) following BDR (r = 0.600, p = 0.004). Most of the infectious pathogens isolated from the liver were also isolated from the hepaticojejunostomy. The changes in hemoglobin, bilirubin, albumin, and ammonia significantly correlated with the changes of the bacterial concentration of the liver. The results of the study suggests that hepatic bacterial proliferation after BDR is significantly affected by microbial overgrowth in the bilioenteric anastomosis and is associated with deteriorated liver function and hemogram.  相似文献   
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