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41.
This study investigated the hypothesis that the insertion/deletion (4G/5G) polymorphism of the plasminogen activator inhibitor type-1 gene affects the risk for ischemic stroke, since results concerning this association have been controversial. We therefore performed a meta-analysis of published data regarding this issue. A comprehensive electronic search was carried out until January 2006. The analysis was performed using random-effects models and meta-regression. Eighteen eligible studies were retrieved (15 case-control studies and three cohort studies). The case-control studies included 3104 cases and 4870 control individuals concerning the contrast of 4G/4G versus remaining genotypes. The 4G pooled allele frequencies in cases and controls were 54.21 and 54.75%, respectively. Overall, the per-allele odds ratio of the 4G allele was 0.98 (95% confidence interval, 0.858-1.121). Regarding genotypes, we derived nonsignificant odds ratios in all contrasts. The subanalysis including the three studies with a prospective design in the 4G/4G versus 5G/5G contrast derived a significant result (relative risk, 0.523; 95% confidence interval, 0.353-0.775), but the estimated effect size was insignificant when cohort and case-control studies were analyzed together (relative risk, 0.848; 95% confidence interval, 0.662-1.087). We failed to demonstrate a significant association between the 4G/5G polymorphism and ischemic stroke under basal conditions. Determination of plasminogen activator inhibitor type-1 function seems of much higher clinical value than determination of the 4G/5G polymorphism. The effect of this genotype on risk of ischemic stroke in acute stressful diseases and the role of cohort studies in genetic epidemiology, however, warrant further investigation.  相似文献   
42.
Antiphospholipid syndrome (APS) is an autoimmune condition characterized by thrombosis and/or recurrent fetal loss as well as the presence of autoantibodies against epitopes present on phospholipid-binding proteins. The role of cellular immunity in the pathogenesis of the syndrome remains unclear. We studied the cellular phenotype and the production of type 1 [interferon (IFN)-, interleukin (IL)-2] and type 2 (IL-4, IL-10) cytokines by CD4+ and CD8+ T-lymphocyte subsets in 13 patients with untreated primary APS (PAPS) and in 32 healthy controls. The production of cytokines was determined in T cells after a 5-h culture with or without mitogenic stimulation using a flow cytometric method of intracellular cytokine staining. In six of the patients these studies were repeated 6 months later. In PAPS patients we found a reduced percentage of circulating CD4+CD45RA+ and an increased percentage and absolute number of CD8+HLA-DR+ cells. A type 1 response was observed in the patients unstimulated cells, indicated by an increase in IFN--producing CD8+, IL-2-producing CD4+ T cells, and a decrease in IL-4-producing CD4+ and CD8+ T cells. Similar results were obtained in the patients at follow-up. Taken together, these results suggest a chronic in vivo stimulation of CD4+ and CD8+ T cells in PAPS patients exhibiting a type 1 polarization. Changes of cellular immunity may contribute to the pathogenesis of the clinical manifestations of the syndrome and might be proven to be useful targets for therapeutic interventions in the future.  相似文献   
43.
Thyroid invasion by Aspergillus spp. can occur with invasive aspergillosis, although it is rarely diagnosed antemortem. We describe a case of multiple thyroid abscesses from A. fumigatus that caused esophageal obstruction in a patient with myelodysplasia. Despite aggressive antifungal treatment, the outcome was rapidly fatal.  相似文献   
44.
Interest in Brucella species as a biological weapon stems from the fact that airborne transmission of the agent is possible. It is highly contagious and enters through mucous membranes such as the conjunctiva, oropharynx, respiratory tract and skin abrasions. It has been estimated that 10-100 organisms only are sufficient to constitute an infectious aerosol dose for humans. Signs and symptoms are similar in patients whatever the route of transmission and are mostly non-specific. Symptoms of patients infected by aerosol are indistinguishable from those of patients infected by other routes. Regimens containing doxycycline plus streptomycin or doxycycline plus rifampin are effective for most forms of brucellosis. Isolation of patients is not necessary. Trimethoprim-sulfamethoxazole and fluoroquinolones also have good results against Brucella, but are associated with high relapse rates when used as monotherapy. The combination of ofloxacin plus rifampicin is associated with good results. Even if there is little evidence to support its utility for post-exposure prophylaxis, doxycycline plus rifampicin is recommended for 3 to 6 weeks.  相似文献   
45.
Long-term outcome of pneumatic dilation in the treatment of achalasia   总被引:8,自引:0,他引:8  
OBJECTIVE: Achalasia is a well-defined esophageal motor disorder for which pneumatic dilation is an established therapeutic method. Even though it has been used for several years, there are limited data on the long-term outcomes of patients treated with this procedure. Hence, we aimed to evaluate the long-term efficacy of pneumatic dilation to control the symptoms of achalasia. METHODS: The medical records of all patients treated in our unit for achalasia with pneumatic dilation were reviewed. We identified the long-term result of the initial procedure, the date of the first dilation, and the time interval between dilation and retreatment. RESULTS: Of 260 patients who were treated with pneumatic dilation, 153 (67 men, 86 women) were followed up for more than 5 yr. The mean follow-up period was 11.09 +/- 3.91 yr, and the success rate of the dilation was 75.8%. Among these patients, 35 (19 men, 16 women) had follow-up periods of more than 15 yr. The mean follow-up time of those patients was 16.56 +/- 1.09 yr, and the success rate was 51.4%. Kaplan-Meier survival analysis showed that, overall, 50% of patients develop recurring symptoms after 10.92 yr. CONCLUSIONS: Although 51.4% of patients continued to be in clinical remission more than 15 yr after the initial pneumatic dilation, the long-term success rate of pneumatic dilation seems to drop progressively with time.  相似文献   
46.
47.
Sirolimus-eluting stents have been used in our institution for all percutaneous interventions, without clinical or anatomic exclusion criteria, as part of the Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital registry. We analyzed the incidence of (sub)acute stent thrombosis after sirolimus-eluting stent implantation in an unselected population of 510 consecutive patients. At 3-month follow-up, (sub)acute stent thrombosis was diagnosed in 2 patients (0.4%) 6 hours and 11 days after the procedure, respectively. These cases occurred in diabetic women with complex coronary lesions. Intravascular ultrasound examination showed inadequate stent expansion and uncovered distal dissection as possible mechanical explanations for the thrombosis.  相似文献   
48.
49.
Dikensoy O  Zhu Z  Donnelly E  Stathopoulos GT  Lane KB  Light RW 《Chest》2005,128(5):3735-3742
BACKGROUND: It has been suggested that talc and doxycycline might be acting through different pathways in creating pleurodesis. We hypothesized that combining doxycycline and talc in half the usual doses would be synergistic in inducing pleurodesis. METHODS: Thirty-two rabbits were equally allocated into four groups: group 1, half-dose combination (5 mg/kg of doxycycline and 200 mg/kg of talc slurry); group 2, quarter-dose combination (2.5 mg/kg of doxycycline and 100 mg/kg of talc slurry); group 3, half-dose doxycycline (5 mg/kg of doxycycline); and group 4, half-dose talc (100 mg/kg of talc slurry). The pleurodesis scores from historical groups that received a full dose of talc (400 mg/kg) or doxycycline (10 mg/kg) were also compared to those obtained in the current study. Pleural fluid lactate dehydrogenase and protein levels were measured 24 h after the injection. Pleurodesis was graded from 1 (none) to 8 (> 50% symphysis) by two observers blinded to treatment groups. All rabbits underwent an ultrasonic examination on each side of their chest for the evaluation of pleurodesis. RESULTS: The mean pleurodesis score in the half-dose combination group was significantly higher than that in the half-dose talc group, half-dose doxycycline group, and the historical full-dose talc group (p = 0.009, p = 0.01, and p < 0.05, respectively). The quarter-dose combination group also had a significantly higher mean pleurodesis score compared to the half-dose talc group (p = 0.013). The difference between the historical full-dose doxycycline and the half-dose combination or quarter-dose combination groups was not significant (p > 0.05). A significantly positive correlation existed between the pleurodesis score and the ultrasound scores (r = 0.876, p = 0.000000005). CONCLUSIONS: This study demonstrates that the combination of half doses of talc and doxycycline is more effective than the half dose of either drug alone or the full dose of talc in producing pleurodesis in rabbits. In addition, ultrasound is an accurate imaging modality for the evaluation of pleurodesis, in that the absence of pleural gliding on ultrasound correlates well with the presence of a pleurodesis in rabbits.  相似文献   
50.
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