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101.
ObjectiveTo understand social media growth in both diagnostic and interventional radiology compared to other related specialties by quantifying and comparing hashtag utilization at annual medical conferences.MethodsOfficial annual conference hashtags for Society of Interventional Radiology (SIR), American College of Radiology (ACR), Radiological Society of North America, American College of Cardiology, American Heart Association, and American Society of Clinical Oncology were analyzed from 2015 to 2019, along with the IR hashtag #IRad. Twitter analytics were obtained with the use of Symplur Signals, a healthcare social media analytics platform. Linear regression analysis was performed on the number of tweets and users for each hashtag.ResultsFor annual ACR meetings, the number of tweets/user (6.96 in 2019), retweets/user (4.39 in 2019), and impressions/user (40,051 in 2019) were among the highest of all the specialties studied. This trend was observed despite a smaller number of users among ACR than most other conferences. SIR tweets increased significantly at a rate of 1032.8 tweets/year (P = 0.008) while users also significantly grew at a rate of 212.5 users/years (P = 0.007). #IRad tweets are also growing at a rate of 13,234.8 tweets/year (P = 0.026) while #IRad users are growing at a rate of 1309.5 users/year (P = 0.003). Radiological Society of North America users were significantly decreasing at ?1207.1 users/year (P = 0.018).ConclusionACR consistently had one of the highest counts of tweets/user, retweets/user, and impressions/user compared to the other studied specialties, suggesting that ACR's Twitter users are more active than users outside of the field of radiology. SIR was the only studied specialty conference that had statistically significant increases in the number of tweets and users.  相似文献   
102.
Sequestration of Plasmodium falciparum-infected erythrocytes (PfIE) in the capillaries of the central nervous system (CNS) is the pathognomonic feature of cerebral malaria, a condition frequently leading to death. Sequestration of PfIE in the placental intervillous spaces is the characteristic feature of malaria in pregnancy and is associated with low birthweight and prematurity. Although both patterns of sequestration are thought to result from the expression of different parasite proteins involved in cytoadhesion to human receptors, scant information exists on whether both conditions can coexist and whether this can lead to death. We conducted a prospective autopsy study including all consecutive pregnancy-related deaths in a tertiary-level referral hospital in Maputo, Mozambique, between October 2002 and December 2006. Extensive sampling of all major viscera was performed. All cases showing parasites in any of the viscera were included in the analysis. From 317 complete autopsies PfIEs were identified in ten women (3.2%). All cases showed massive accumulation of PfIE in small capillaries of the CNS but also in most visceral capillaries (heart, lung, kidney, uterus). Placental tissue, available in four cases, showed a massive accumulation of maternal PfIE in the intervillous space. Coma (six women) and dyspnoea (five women) were the most frequent presenting clinical symptoms. In conclusion, massive visceral sequestration of PfIE with significant involvement of the CNS is an infrequent but definite direct cause of maternal death in endemic areas of Africa. The PfIE sequestered in cerebral capillaries and the placenta coexist in these fatal cases.  相似文献   
103.
We herein have developed a mild approach for the fabrication of glauconite clay (G)-modified chitosan (CS) nanocomposites by the combination of a simple blending and crosslinking method. The chitosan was modified with ethylenediaminetetraacetic acid (EDTA), glutaraldehyde (GL), sodium dodecyl sulfate (SDS), and cetyltrimethyl ammonium bromide (CTAB). The as-prepared composites were identified using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), nitrogen physical adsorption (BET), atomic absorption spectrophotometry (AA), and thermal gravimetric analysis (TGA). The adsorption activities of the as-prepared materials were assessed for the removal of fluoride ions from aqueous media using a batch technique. Raw glauconite (G), GL-CS/G, SDS-CS/G, EDTA-GL-CS/G, and CTAB-CS/G adsorbents displayed maximum adsorption capacity values of 1.15, 4.31, 4.55, 6.90, and 9.03 mg g−1, respectively. The adsorption results were well described by employing the pseudo-second-order kinetic and Langmuir isotherm models. The estimated thermodynamic constants indicated that the F ion adsorption was a spontaneous, physisorption process. Furthermore, the modified chitosan adsorbents are good candidates for the adsorptive elimination of F ions from aqueous solutions, according to their reusability, high stability, good adsorption capacity, and applicability for actual field water samples.

We herein have developed a mild approach for the fabrication of glauconite clay (G)-modified chitosan (CS) nanocomposites by the combination of a simple blending and crosslinking method.  相似文献   
104.
Catheter/endoscope-based optical coherence tomography (OCT) is a powerful modality that visualizes structural information in luminal organs. Increases in OCT speed have reduced motion artifacts by enabling acquisition faster than or comparable to the time scales of physiological motion. However motion distortion remains a challenge because catheter/endoscope OCT imaging involves both circumferential and longitudinal scanning of tissue. This paper presents a novel image processing method to estimate and correct motion distortion in both the circumferential and longitudinal directions using a single en face image from a volumetric data set. The circumferential motion distortion is estimated and corrected using the en face image. Then longitudinal motion distortion is estimated and corrected using diversity of image features along the catheter pullback direction. Finally, the OCT volume is resampled and motion corrected. Results are presented on synthetic images and clinical OCT images of the human esophagus.  相似文献   
105.
IntroductionPassive antibody therapy has been used to immunize vulnerable people against infectious agents. In this study, we aim to investigate the efficacy of convalescent plasma (CP) in the treatment of severe and critically ill patients diagnosed with COVID-19.MethodThe data of severe or critically ill COVID-19 patients who received anti-SARS-CoV-2 antibody-containing CP along with the antiviral treatment (n = 888) and an age-gender, comorbidity, and other COVID-19 treatments matched severe or critically ill COVID-19 patients at 1:1 ratio (n = 888) were analyzed retrospectively.ResultsDuration in the intensive care unit (ICU), the rate of mechanical ventilation (MV) support and vasopressor support were lower in CP group compared with the control group (p = 0.001, p = 0.02, p = 0.001, respectively). The case fatality rate (CFR) was 24.7 % in the CP group, and it was 27.7 % in the control group. Administration of CP 20 days after the COVID-19 diagnosis or COVID-19 related symptoms were associated with a higher rate of MV support compared with the first 3 interval groups (≤5 days, 6?10 days, 11?15 days) (p=0.001).ConclusionCP therapy seems to be effective for a better course of COVID-19 in severe and critically ill patients.  相似文献   
106.
107.
Heterotopic pancreas is a relatively common variant of foregut embryologic dystopia that can be described as pancreatic tissue found outside the normal anatomic location, being independent from vascular supply of normal pancreas. Having all features of pancreatic tissue except for the major duct structures, this ectopic tissue may be clinically recognized when pathologic changes take place. Inflammation, hemorrhagic or obstructive states, and eventually malignancy-related problems may become a diagnostic challenge for clinician and finally lead to consequences of misdiagnosis. In this article we will discuss a case of heterotopic pancreatic tissue located in gastric cardia, which was diagnosed preoperatively as gastrointestinal stromal tumor.Key words: Ectopic pancreas, Pseudocyst, Gastrointestinal stromal tumor, MisdiagnosisHeterotopic (ectopic) pancreas is defined as the presence of pancreatic tissue in an aberrant site that is not anatomically and vascularly connected to the pancreas proper.1,2 Ectopic pancreatic tissue is most commonly found in the duodenum (particularly the second portion), ampulla, stomach (prepyloric antrum), and upper jejunum; it can also occur in the liver, biliary tract, Meckel''s diverticulum, and several other sites such as large bowel, spleen, omentum, mediastinum, lung, thyroid, and even brain.16 The heterotopic pancreatic tissue is usually located in the submucosa and/or the muscularis or subserosa.1,2,4Practically any pancreatic pathology can also occur in the heterotopic pancreatic tissue including acute pancreatitis and neoplastic transformation.1,4,7,8 Episodes of acute pancreatitis may cause local inflammation and typical pancreatitis-related complications in the host organ. The ectopic pancreatic tissue can lead to ulceration and bleeding in the cases located beneath a mucosa. Being a mass-forming lesion, it may also result in luminal obstruction (particularly in the prepyloric antrum).1,4Although it is a relatively common congenital anomaly (0.5% to 13% in autopsy series), in most cases heterotopic pancreas remains clinically silent and is found incidentally during surgery or an endoscopic and/or radiological investigation.1,9 Heterotopic pancreas may be confused with other solid tumors of the host organ.Heterotopic pancreas in the stomach is usually located in the prepyloric area.10 We report here an unusual case of heterotopic pancreas with a pseudocyst formation in the gastric cardia mimicking gastrointestinal stromal tumor.  相似文献   
108.
109.
The bipolar radiofrequency device (Habib®) has been recently introduced in order to reduce intraoperative bleeding for a safe hepatic resection as an alternative to the conventional tools. However, indications, perioperative findings, and outcome of the device for hepatic resections remain and deserve to be analyzed. The current study aims to analyze the feasibility of the bipolar radiofrequency device (Habib®) for hepatic resections. Information of the patients that underwent hepatic resection using with the Habib® device between 2007 and 2011 was abstracted. Patient, disease, and operation-related findings and perioperative data were investigated. A total of 71 cases (38 [53.5 %] males, mean age was 56.8 ± 11.9) were analyzed. Metastatic disease (n = 55; 77.5 %) was the leading indication followed by primary liver and biliary malignancies (n = 7; 9.9 %), hemangioma (n = 5; 7 %), hydatid disease (n = 3; 2.8 %), and hepatic gunshot trauma (n = 1; 1.4 %). Metastasectomy was the most commonly performed procedure (n = 31; 56.3 %), but in 24 (77.4 %) cases, it was performed in addition to extended resections. Other procedures in the study patients include segmentectomy in 17, bisegmentectomy in 19, trisegmentectomy in 17, right or left hepatectomy in 8, and extended right/left hepatectomy in 3. The mean (±SD) operation time was 241.7 ± 78.2 min. The median amount of bleeding was 300 cc (range 25–2500), and 23 (32.4 %) cases required perioperative transfusion. The median hospitalization period was 5 days (range 1–47). Lengthened drainage (n = 9, 12.7 %) and intraabdominal abscess (n = 8, 11.23 %) were the most common problems. Hepatic resections using the Habib® device seem to be feasible in cases with primary and metastatic hepatic lesions and benign liver masses and even those with hepatic trauma. It may lessen the amount of intraoperative hemorrhage, although lengthened drainage and intraabdominal abscess were the major postoperative problems in these cases.  相似文献   
110.
Pulmonary resections comprise most of the operations performed in thoracic surgery departments. Diseases like pulmonary cancers, bronchiectasis, pulmonary abscess, tuberculosis and fungal infections are treated surgically by pulmonary resections. One of the important steps of the pulmonary resection is to suture the bronchi through which the air is supplied to the resected pulmonary tissue. Bronchopleural fistula developed in the bronchial stump is encompassed as one of the most important factors affecting mortality and morbidity regarding postoperative complications.  相似文献   
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