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Radiofrequency (RF) catheter ablation has ushered in a new era in the management of patients with symptomatic tachyarrhythmias. By providing the ability to cure the underlying arrhythmic substrate, RF catheter ablation obviates the need for life-long antiarrhythmic drugs. In the reported series, the success has been high and the complications have been infrequent and relatively minor. Not unexpectedly, RF catheter ablation has become the treatment of choice for patients with symptomatic paroxysmal tachyarrhythmias. The role of radiofrequency catheter ablation in infants and small children remains controversial, and awaits a larger experience and longer follow-up data.  相似文献   
43.
Kindling has been suggested as a possible mechanism for cocaine-induced seizures in chronic cocaine abusers, even though no convincing examples have been reported. We report a 37-year-old woman who initially experienced generalized tonic-clonic seizures (GTC) only immediately after "crack" use. She had a normal examination, negative family or past history for seizures, and normal cranial computed tomography and EEG. After she had abused cocaine almost daily for 2 years, her EEG demonstrated bitemporal slowing with independent spikes, and seizures were no longer temporally associated with acute cocaine use. Thereafter, despite complete abstinence from cocaine and treatment with phenytoin, she continued to experience four to six GTC a month. In light of the lack of other predisposing factors for epilepsy, this case may represent an example of cocaine-induced kindling in humans.  相似文献   
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In 2019, Burkholderia pseudomallei was isolated from the backyard of 2 siblings with melioidosis in Kerala, India. This finding highlights the value of healthcare providers being aware of risk for melioidosis in febrile patients, of residents taking precautions when outside, and of increasing environmental surveillance for B. pseudomallei in this region.  相似文献   
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Zika virus (ZIKV) causes significant human diseases without specific therapy. Previously we found erythrosin B, an FDA-approved food additive, inhibited viral NS2B−NS3 interactions, leading to inhibition of ZIKV infection in cell culture. In this study, we performed pharmacokinetic and in vivo studies to demonstrate the efficacy of erythrosin B against ZIKV in 3D mini-brain organoid and mouse models. Our results showed that erythrosin B is very effective in abolishing ZIKV replication in the 3D organoid model. Although pharmacokinetics studies indicated that erythrosin B had a low absorption profile, mice challenged by a lethal dose of ZIKV showed a significantly improved survival rate upon oral administration of erythrosin B, compared to vehicle control. Limited structure−activity relationship studies indicated that most analogs of erythrosin B with modifications on the xanthene ring led to loss or reduction of inhibitory activities towards viral NS2B−NS3 interactions, protease activity and antiviral efficacy. In contrast, introducing chlorine substitutions on the isobenzofuran ring led to slightly increased activities, suggesting that the isobenzofuran ring is well tolerated for modifications. Cytotoxicity studies indicated that all derivatives are nontoxic to human cells. Overall, our studies demonstrated erythrosin B is an effective antiviral against ZIKV both in vitro and in vivo.KEY WORDS: Flavivirus, Zika virus, Dengue virus, Antiviral, Protease inhibitor, Erythrosin B  相似文献   
48.
Cancer therapy is a fast-emerging biomedical paradigm that elevates the diagnostic and therapeutic potential of a nanovector for identification, monitoring, targeting, and post-treatment response analysis. Nanovectors of superparamagnetic iron oxide nanoparticles (SPION) are of tremendous significance in cancer therapy because of their inherited high surface area, high reactivity, biocompatibility, superior contrast, and magnetic and photo-inducibility properties. In addition to a brief introduction, we summarize various progressive aspects of nanomagnets pertaining to their production with an emphasis on sustainable biomimetic approaches. Post-synthesis particulate and surface alterations in terms of pharmaco-affinity, liquid accessibility, and biocompatibility to facilitate cancer therapy are highlighted. SPION parameters including particle contrast, core-fusions, surface area, reactivity, photosensitivity, photodynamics, and photothermal properties, which facilitate diverse cancer diagnostics, are discussed. We also elaborate on the concept of magnetism to selectively focus chemotherapeutics on tumors, cell sorting, purification of bioentities, and elimination of toxins. Finally, while addressing the toxicity of nanomaterials, the advent of ultrasmall nanomagnets as a healthier alternative with superior properties and compatible cellular interactions is reviewed. In summary, these discussions spotlight the versatility and integration of multi-tasking nanomagnets and ultrasmall nanomagnets for diverse cancer theragnostics.  相似文献   
49.
Timely follow‐up for positive cancer screening results remains suboptimal, and the evidence base to inform decisions on optimizing the timeliness of diagnostic testing is unclear. This systematic review evaluated published studies regarding time to follow‐up after a positive screening for breast, cervical, colorectal, and lung cancers. The quality of available evidence was very low or low across cancers, with potential attenuated or reversed associations from confounding by indication in most studies. Overall, evidence suggested that the risk for poorer cancer outcomes rises with longer wait times that vary within and across cancer types, which supports performing diagnostic testing as soon as feasible after the positive result, but evidence for specific time targets is limited. Within these limitations, we provide our opinion on cancer‐specific recommendations for times to follow‐up and how existing guidelines relate to the current evidence. Thresholds set should consider patient worry, potential for loss to follow‐up with prolonged wait times, and available resources. Research is needed to better guide the timeliness of diagnostic follow‐up, including considerations for patient preferences and existing barriers, while addressing methodological weaknesses. Research is also needed to identify effective interventions for reducing wait times for diagnostic testing, particularly in underserved or low‐resource settings. CA Cancer J Clin 2018;68:199–216 . © 2018 American Cancer Society .  相似文献   
50.
OBJECTIVE: To assess whether supracervical hysterectomy (SCH) is a reasonable alternative to total abdominal hysterectomy in patients with advanced ovarian cancer. METHODS: We reviewed the records of patients with advanced ovarian cancer who underwent a SCH at one institution between 1993 and 2004 and a similar cohort who underwent total abdominal hysterectomy (TAH) at the same institution during the same period. Patients without complete surgical staging done at the institution were excluded. Independent-sample t tests, Fisher exact test, and log rank tests were used for statistical analysis. RESULTS: The study included 47 patients who underwent SCH (mean age, 59.6 years) and 190 who underwent TAH. There were no significant differences between the two groups in age (P=.51), preoperative CA 125 level (P=.55), or receipt of taxane-based and platinum-based chemotherapy (P=.84). Although limited by sample size, there were no significant differences between the two groups in rates of intraoperative complications (4 of 47 in the SCH group, or 8.5%, compared with 7 of 190 in the TAH group, or 3.7%; P=.24), vaginal or cervical recurrence (5 of 47 in the SCH group, or 10.6%, compared with 22 of 190 in the TAH group, or 11.6%; P=1.00), or in progression-free survival (SCH of 1.01 years compared with TAH of 1.19 years; P=.64) or overall survival (SCH of 3.28 years compared with TAH of 3.36 years; P=.12). CONCLUSION: Supracervical hysterectomy may be a reasonable alternative to TAH in patients with advanced ovarian cancer. LEVEL OF EVIDENCE: II.  相似文献   
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