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21.

Objectives

Fake news: misinformation and falsehood of health news in social media constitute a potential threat to the public health, but the scope of this issue remains unclear. Our pilot study is an initial attempt to measure a number of the top shared health misinformation stories in the Polish language social media.

Methods

Using the BuzzSumo Application, a range of the top shared health web links in the Polish language social media was assessed during the period between 2012 and 2017. We used the following keywords which were related to the most common diseases and causes of death: cancer, neoplasm, heart attack, stroke, hypertension, diabetes, vaccinations, HIV, and AIDS. Each link was checked for the presence of fake news.

Results

40% of the most frequently shared links contained text we classified as fake news. These were shared more than 450,000 times. The most fallacious content concerned vaccines, while news about cardiovascular diseases was, in general, well sourced and informative. More than 20% of dangerous links from our material was generated by one source.

Conclusions

Analyzing social media top shared news could contribute to identification of leading fake medical information miseducating the society. It might also encourage authorities to take actions such as put warnings on biased domains or scientifically evaluate those generating fake health news.  相似文献   
22.
In the present work, we investigated in detail the thermal/crystallization behavior and magnetic properties of materials with Fe84.5-xCoxNb5B8.5P2 (x = 0, 5, 10, 15 and 20 at.%) composition. The amorphous ribbons were manufactured on a semi-industrial scale by the melt-spinning technique. The subsequent nanocrystallization processes were carried out under different conditions (with/without magnetic field). The comprehensive studies have been carried out using differential scanning calorimetry, X-ray diffractometry, transmission electron microscopy, hysteresis loop analyses, vibrating sample magnetometry and Mössbauer spectroscopy. Moreover, the frequency (up to 300 kHz) dependence of power losses and permeability at a magnetic induction up to 0.9 T was investigated. On the basis of some of the results obtained, we calculated the values of the activation energies and the induced magnetic anisotropies. The X-ray diffraction results confirm the surface crystallization effect previously observed for phosphorous-containing alloys. The in situ microscopic observations of crystallization describe this process in detail in accordance with the calorimetry results. Furthermore, the effect of Co content on the phase composition and the influence of annealing in an external magnetic field on magnetic properties, including the orientation of the magnetic spins, have been studied using various magnetic techniques. Finally, nanocrystalline Fe64.5Co20Nb5B8.5P2 cores were prepared after transverse thermo-magnetic heat treatment and installed in industrially available portable heating equipment.  相似文献   
23.
BACKGROUND: Intravenous glycoprotein GP IIb/IIIa receptor antagonists administered to patients with acute coronary syndromes limit platelet-dependent thrombus formation and vasoconstriction and lower the complication rate of PCI. The efficacy of glycoprotein IIb/IIIa inhibitors critically depends on appropriate suppression of platelet aggregation. A growing body of evidence indicates that regimen of tirofiban used in several recent trials may be suboptimal. We investigated if a novel regimen of dosage of tirofiban administered to patients with acute myocardial infarction with ST elevation (STEMI) before primary angioplasty is safe, feasible and whether such treatment improves coronary flow in infarct-related artery. METHODS: It was an open-label, non-randomized, prospective observational study. 253 consecutive patients with STEMI, qualified to PCI were included. 104 of patients (group 1) received heparin plus tirofiban at a novel regimen (10 microg/kg bolus, followed by 0.4 microg/kg/min for 30 min and then 0.1 microg/kg/min for 12-24 hours) and the remaining 149 of the patients (group 2) received a standard dose of heparin prior to PCI. Bleeding complications were recorded. The primary end point of the study was combined TIMI 1 + 2 + 3 grade flow at the time of first contrast medium injection during angiography for primary PCI. RESULTS: Heparin was administered 50.3 +/- 58.1 minutes (group 1) or 62.3 +/- 67.3 minutes (group 2) ( p = 0.205). Tirofiban was administered for an average of 14.5 +/- 14.4 minutes before TIMI assessment (group 1). In patients treated with heparin + tirofiban the rate of combined TIMI 1 + 2 + 3 coronary flow was higher (38.4% vs. 24.8%, p = 0.020) as compared to patients treated with heparin alone. The difference in the rate of TIMI > or = 2 coronary blood flow between the groups 1 and 2 (24.0% vs. 20.1%) has not reached statistical significance ( p = 0.459). At the same time the significant difference in the rate of TIMI 1 coronary blood flow between the groups 1 and 2 was noted (14.4 vs. 4.7%, p = 0.007). In hospital mortality in the groups 1 and 2 was similar (5.3 vs. 4.8%, p = 0.838). Significant difference was noted between the groups 1 and 2 with regard to minor bleeding complications (17.3 vs. 8.7%, p = 0.041). CONCLUSION: In patients undergoing primary angioplasty for acute myocardial infarction the novel regimen of tirofiban is well tolerated and feasible, and is associated with improvement in coronary blood flow in the infarct related artery. Larger studies assessing the effects of tirofiban on clinical outcomes of patients with AMI undergoing primary angioplasty seem worthwhile.  相似文献   
24.
25.
Preclinical studies in our laboratory have demonstrated that prior exposure to hydroxyurea increases the percentage of cells in S phase, enhancing the cytotoxicity of subsequent gemcitabine treatment in human oropharyngeal KB cells. To evaluate the clinical implications of this time- and sequence-dependent potentiation, we performed a phase I trial of hydroxyurea given over 24 h followed by a 30-min infusion of gemcitabine in weeks 1 and 2 of a 3-week cycle. The dose of hydroxyurea was fixed at 500 mg orally every 6 h for four doses starting 24 h before each dose of gemcitabine. The initial dose level of gemcitabine was 250 mg/m(2) on days 2 and 9, and this was escalated stepwise to 1000 mg/m(2) on days 2 and 9. Gemcitabine pharmacokinetics were determined on days 2 and 9 of the first cycle. Of 27 patients enrolled (12 female, 15 male), 24 were evaluable for response and 23 were evaluable for toxicity. Their median age was 56 years (range 27-76 years). Tumor types included lung, head and neck, pancreas, breast, colon, prostate, stomach, ovary, esophagus, germ cell, thyroid, gallbladder, and unknown primary. A total of 80 cycles of treatment were completed. One patient (unknown primary) had an objective partial response lasting 21 months, and 12 patients had stable disease. All observed dose-limiting toxicities were related to myelosuppression. The gemcitabine maximum tolerated dose was established at 750 mg/m(2) on days 2 and 9. Hydroxyurea had no effect on the plasma pharmacokinetics of gemcitabine. These results suggest that hydroxyurea followed by gemcitabine can be safely administered and has activity on this schedule. We are presently developing a phase II trial of this regimen for patients with platinum-resistant head and neck cancer.  相似文献   
26.
BACKGROUND: BMS-275291 is a selective matrix metalloproteinase inhibitor (MMPI) that does not inhibit sheddases implicated in the dose-limiting arthritis of older MMPIs. We conducted a randomized phase II trial of two doses of BMS-275291 (1,200 versus 2,400 mg) in hormone-refractory prostate cancer (HRPC) patients with bone metastases to probe for a dose-response relationship and to assess differential toxicities. Serial serum and urine specimens were collected to assess for markers of bone metabolism. METHODS: The primary end point was 4-month progression-free survival (PFS). Eligibility criteria included documentation of androgen-independent disease (including anti-androgen withdrawal), skeletal metastasis, adequate end-organ function and performance status, and no more than one prior chemotherapy regimen. Patients were randomized to 1,200 mg orally once daily (arm A) or 1,200 mg orally twice daily (arm B). Response was assessed every 56 days. RESULTS: Eighty patients were enrolled: 39 in arm A and 41 in arm B. There were no responders by prostate-specific antigen or measurable disease to treatment. Stable disease was noted at 8 weeks in 39% of patients in arm A and in 17% of patients in arm B. Progression of disease at 8 weeks was seen in 61% of patients in arm A versus 83% of patients in arm B. Median survival time was 21.6 months (95% confidence interval, 17.5; not reached), whereas median PFS time was 1.8 months (95% confidence interval 1.74; 2) for all patients. Patients in arm A had a median survival time that was not reached, whereas patients on arm B has a median survival time of 21 months (P = 0.2). PFS at 4 months favored arm A: 22% versus 10% (log-rank, P = 0.008). Grade 3 toxicities occurred in 5 (13%) patients in arm A and in 9 (22%) patients in arm B. Grade 4 toxicities were uncommon (only 4% of patients): one each of thrombosis, fatigue, and motor neuropathy was seen in the arm B. Bone marker studies showed that baseline serum levels of N-telopeptide, osteocalcin, procollagen I NH2-terminal propeptide, and PICP had prognostic significance for PFS and/or overall survival. CONCLUSIONS: Regardless of dose schedule, BMS-275291 was well tolerated in HRPC patients and had no dose-limiting arthritis. Toxicities differed modestly according to the dose schedule employed. As overall survival and PFS favored the once daily schedule, this dose schedule is recommended for future studies. Baseline markers of bone metabolism may have prognostic value in HRPC patients with bone metastases.  相似文献   
27.
Studies have shown white beans to be an effective fat replacer in dropped cookies. However, research is needed to determine whether legumes may be an effective replacement for fat in other types of cookies. This study determined the overall acceptability, sensory characteristics, and nutrient content of brownies (bar cookie) made using cannellini beans as a replacement for shortening. Cannellini beans were used to replace 25%, 50%, and 75% of the shortening (by weight) in a control brownie formula. One hundred twenty untrained panelists participated in rating the brownies on a seven-point hedonic scale. Analysis of variance conducted on the acceptability and sensory characteristics indicated a statistically significant effect when replacing fat with beans for acceptability, tenderness, texture, and flavor (P<.05). Post-hoc testing (Scheffe's test) indicated that neither the 25% nor the 50% bean brownies were significantly different from the control in overall acceptability, tenderness, texture, or flavor. Also, the 50% bean brownies, compared with control, had 2.6 g less fat and 21 fewer kcal per 1.4-oz serving. This study demonstrated that pureed cannellini beans can replace as much as 50% of the fat (by weight) in brownies, while yielding an acceptable and more nutritious product.  相似文献   
28.
The genetics of geometry   总被引:1,自引:0,他引:1       下载免费PDF全文
Although much progress has been made in understanding how gene expression patterns are established during development, much less is known about how these patterns are related to the growth of biological shapes. Here we describe conceptual and experimental approaches to bridging this gap, with particular reference to plant development where lack of cell movement simplifies matters. Growth and shape change in plants can be fully described with four types of regional parameter: growth rate, anisotropy, direction, and rotation. A key requirement is to understand how these parameters both influence and respond to the action of genes. This can be addressed by using mechanistic models that capture interactions among three components: regional identities, regionalizing morphogens, and polarizing morphogens. By incorporating these interactions within a growing framework, it is possible to generate shape changes and associated gene expression patterns according to particular hypotheses. The results can be compared with experimental observations of growth of normal and mutant forms, allowing further hypotheses and experiments to be formulated. We illustrate these principles with a study of snapdragon petal growth.  相似文献   
29.
The combination of a nitric oxide (NO) donor and a paclitaxel-NO donor conjugate coated on a vascular stent was tested in a rabbit iliac artery model of stenosis as a potential therapy for restenosis. Paclitaxel was conjugated with a NO donor at the 7-position to give compound 7. An adamantane-based NO donor 14 was synthesized and combined with 7 to provide a burst of NO in the first few critical hours following injury to the vessel wall. Both 7 and 14 demonstrated antiproliferative activity (IC(50) = 20 nM and 15 microM, respectively) and antiplatelet activity (IC(50) = 10 and 1 microM, respectively). Stents were coated with a layer of a polymer containing test compounds. The total amount of NO eluted from the stents after a 6 h implantation in the rabbit iliac artery was 35%, 95%, and 69% of the original content for the stents coated with 7, 14, and the combination of 7 and 14, respectively. The antistenotic activity of 7 and 14 was determined in a 28-day rabbit model with two control groups (uncoated stents and polymer-coated stents) and two study groups (paclitaxel-coated stents and stents coated with the combination of 7 and 14). Polymer-coated stents caused inflammation and increased stenosis by 39% when compared to the uncoated stents. The stents coated with 7 plus 14 were as good as the uncoated stents, 41% better than the polymer-coated stents and 34% better than the paclitaxel-coated stents. These data indicate a beneficial effect of adding NO to an antiproliferative agent (paclitaxel) and suggest a potential therapeutic combination for the treatment of stenotic vessel disease.  相似文献   
30.
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