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Strongyloides hyperinfection syndrome may be complicated by paralytic ileus that interferes with the absorption of oral anti-helminthics. We report on the administration of ivermectin as a rectal enema preparation to a renal transplant recipient with Strongyloides hyperinfection syndrome and progressive ileus. Attempts at treatment using nasogastric albendazole and ivermectin were unsuccessful despite clamping the nasogastric tube after drug administration. Ivermectin tablets were ground to a powder, resuspended in a commercially available suspending agent, and administered per rectum. The suspending agent was chosen for its near-physiologic osmolality to allow longer retention, in contrast to many enema preparations that have a laxative effect. The patient improved markedly within 72 hours of initiation of the therapy per rectum and recovered fully. Ivermectin administered as an enema may be beneficial in patients with severe strongyloidiasis who are unable to absorb or tolerate oral therapy.  相似文献   
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Often as an epidemic spreads, the leading front is irregular, reflecting spatial variation in local transmission rates. We developed a methodology for quantifying spatial variation in rates of disease spread across heterogeneous landscapes. Based on data for epidemic raccoon rabies in Connecticut, we developed a stochastic spatial model of rabies spread through the state's 169 townships. We quantified spatial variation in transmission rates associated with human demography and key habitat features. We found that large rivers act as semipermeable barriers, leading to a 7-fold reduction in the local rates of propagation. By combining the spatial distribution of major rivers with long-distance dispersal we were able to account for the observed irregular pattern of disease spread across the state without recourse to direct assessment of host-pathogen populations.  相似文献   
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Percutaneous nonvascular splenic intervention: a 10-year review   总被引:6,自引:0,他引:6  
OBJECTIVE: We performed a retrospective review of our experiences with percutaneous splenic interventions to evaluate the safety and usefulness of these procedures. We examined both the success rate and the complication rate. MATERIALS AND METHODS: We used our electronic database to perform a retrospective analysis of patients treated from January 1990 to December 2000. Thirty-nine imaging-guided percutaneous splenic procedures were performed in 38 patients: 27 men and 11 women who ranged in age from 17 to 83 years (mean age, 56.5 years). For 28 procedures, sonographic guidance was used, and for 11, CT guidance was used. Procedures performed included splenic biopsy (n = 24), fluid aspiration (n = 8), and fluid drainage (n = 7). RESULTS: Splenic biopsy was successful in 91% of the procedures; fluid aspiration, in 100%; and fluid drainage, in 86%. The overall complication rate was 10.3%, with three patients requiring emergency splenectomy as a result of massive bleeding after the procedure. Two of these patients had previously unrecognized vascular tumors, and one had concomitant refractory thrombocytopenia. CONCLUSION: This study suggests that splenic biopsy can be performed safely and is of considerable value in diagnosis. Our findings also show that percutaneous catheter drainage of splenic abscesses is successful and that splenectomy should be reserved for failed percutaneous drainage. The complications that occur after procedures on vascular tumors emphasize the importance of requiring normal coagulation parameters before the procedure because the vascular nature of the lesion may be difficult to recognize on imaging before the procedure.  相似文献   
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To assess the effect of surfactant replacement therapy (SRT) on the prevalence and severity of retinopathy of prematurity (ROP), we compared data from 160 SRT-treated preterm infants with data from 230 historic controls. The prevalence of ROP was 30.6% in the treatment group and 23.4% in the control group. Severe ROP (stages 3-4) was seen in 6.1% of the infants with ROP in the treatment group and 20.3% of the ROP patients in the control group. Surfactant therapy had no influence on the prevalence of ROP (odds ratio 1.4, 95% confidence interval 0.797-2.459, p = 0.242). However, SRT was associated with a decreased risk for severe ROP, compared to mild ROP (odds ratio 0.226, 95% confidence interval 0.056-0.905, p = 0.036). These data suggest that SRT is associated with a decreased risk for severe ROP.  相似文献   
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To explore the time course and the mechanism of development of bronchial secretory cell metaplasia (SCM) induced by human neutrophil elastase (HNE), anesthetized hamsters were injected intratracheally with 300 micrograms highly purified HNE in 0.5 ml saline solution; saline-injected and untreated animals served as controls. At 3, 8, 16, and 21 days after treatment, animals were killed and their lungs fixed by vascular perfusion. Samples from the hilar region of the left lung, containing the main axial airway and its proximal branches, were embedded in Epon-Araldite, and 1 micron sections were stained with methylene blue. Epithelial cells with a luminal border were categorized into three cell types and expressed as a percent of total cells counted (mean 1900 per animal); cells containing at least three mucin granules were classified as secretory, ciliated cells displayed cilia or basal bodies, and cells with none of these characteristics were classified as indeterminate. Percentages of the three cell types in saline-treated animals, at all time points, were comparable to those in the untreated controls. With HNE treatment the secretory cell percentages were higher at 16 days (mean +/- SEM, 36.4% +/- 3.2%) and at 21 days (35.7% +/- 2.9%) than in the untreated animals (18.2% +/- 1.8%, P less than 0.05). The percentage of the indeterminate cells in the HNE group was decreased at days 8, 16, and 21 (7.2% +/- 1.6%, 5.0% +/- 1.4%, and 8.2% +/- 2.5%, respectively) compared with that in the untreated group (21.7% +/- 2.5%, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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金刚大化学成分的研究   总被引:1,自引:0,他引:1  
从百部科黄精叶钩吻属植物金刚大(Croomia japonica Miq)的根部分得五个成分,分别为粉蕊黄杨胺A(pachysamine A,Ⅰ)、金刚大啶(croomionidine,Ⅱ)、金刚大碱(croomme,Ⅲ)、脱氢金刚大碱(didehydrocroomine,Ⅳ)和β-谷甾醇。应用波谱(IP,MS,1HNMR和13CNMR等)分析、理化数据测定和化学转化,确定丁它们的结构,其中金刚大啶为新甾体生物碱。  相似文献   
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