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931.
932.
Due to the COVID-19 infection, which was recognized as a global pandemic by the WHO on March 11, 2020, the number of cases and disease-related deaths increases day by day globally. For this reason, antiviral agents used in treatment and vaccines, the most effective weapon in prevention, continue to be the most popular topic of the plan. Several situations are expected to affect the course of the pandemic. The loss of the ability of the virus to mutate and cause disease, the fact that those who become immunized by having the disease in the society reach a critical rate and create social immunity (herd immunity), and the provision of social immunity with effective vaccination can be counted as some of these situations.Candidate vaccines in the clinical phase among RNA-based vaccines: This review aimed to examine COVID-19 vaccine candidates using RNA technology and compile its current data. We used PubMed, Google Scholar, and World Health Organization (WHO) databases. Also, we followed up on the latest news and developments on vaccine companies’ websites.Conclusion: Vaccination trials, which started due to the seriousness and urgency of the situation that we are in, continue exceptionally quickly and effectively. As per the WHO›s data on July 9, 2021, there have been 291 vaccine trials, 107 of which are in the clinical phase, and 18 (16%) of the vaccine candidates in the clinical phase are RNA-based vaccines. Also, the number of RNA-based vaccines with ongoing preclinical trials is 2  相似文献   
933.
Objectives:  To test whether the submandibular/sublingual (SMSL) salivary secretion, mucin concentration and candida carriage status were altered in human immunodeficiency virus-positive (HIV+) patients.
Subjects and methods:  SMSL saliva collected from 48 HIV-infected and 31 HIV-negative men were analyzed for flow rates, total protein and mucin concentrations. Salivary cultures were performed for Candida assessment.
Results:  The salivary flow rate and protein secretion of the HIV+ patients was 37% and 32% less than that of the controls ( P  <   0.0001, P  =   0.0087). The mucin concentrations (MG1 and MG2) were higher in the HIV+ subjects compared with controls ( P  =   0.0186, P  =   0.0014); however, the mucin secretions were not different. The frequency of Candida -positive cultures was higher in the HIV+ subjects than in the controls (61.4% vs 24.1%, P  =   0.0018). In the HIV-infected group, the unstimulated SMSL flow rates were lower in Candida -positive than in Candida -negative patients ( P  =   0.0158).
Conclusion:  The salivary secretion of the SMSL glands was reduced in HIV infection. Although the mucin concentration increased in HIV+ subjects, mucin secretion was not altered. Highly active antiviral therapy had no effect on salivary function. We found an association between the level of candida carriage and salivary flow rate in HIV-infected patients.  相似文献   
934.
Shellock  FG; Mink  JH; Deutsch  AL; Fox  JM 《Radiology》1989,172(3):799-804
A kinematic magnetic resonance (MR) imaging technique for assessment of malalignment of the patella, involving the acquisition of multiple sequential axial images of the patellofemoral joint during the early increments of passive knee flexion, was used to evaluate 130 patients (235 symptomatic patellofemoral joints) showing clinical evidence of having patellar tracking abnormalities. Twenty-three of the patellofemoral joints had undergone previous surgical procedures for patellar realignment. In addition, 14 (28 patellofemoral joints) asymptomatic control subjects were studied. Normal patellar tracking was observed in all of the asymptomatic subjects and in 43 (17%) of the 260 patellofemoral joints in the patient population, 18 (7%) of which were symptomatic. Sixty-nine (26%) of the patellofemoral joints had lateral subluxation of the patella, 106 (41%) had medial subluxation of the patella, 21 (8%) had excessive lateral pressure syndrome, 19 (7%) had lateral-to-medial subluxation of the patella, and two (1%) had dislocation of the patella. Of the 235 patellofemoral joints with suspected abnormalities, 217 (93%) had patellar malalignment. Of the 23 patellofemoral joints that had undergone prior surgery, 20 (87%) had abnormal patellar tracking. Thirteen of 14 (93%) patellofemoral joints that had undergone a prior arthroscopic lateral retinacular release had a medially displaced patella.  相似文献   
935.
Chronic wrist pain: evaluation with high-resolution MR imaging   总被引:6,自引:0,他引:6  
The diagnostic performance of magnetic resonance (MR) imaging in the evaluation of the triangular fibrocartilage complex and the intrinsic and extrinsic ligaments of the wrist was assessed in 43 patients with chronic wrist pain. Forty-one patients underwent correlative arthrography. Twenty-three patients underwent arthroscopy or arthrotomy or both. The normal anatomy of the triangular fibrocartilage and the intrinsic and extrinsic ligaments could be demonstrated effectively with MR imaging. MR imaging was effective in the evaluation of triangular fibrocartilage tears with a sensitivity of 1.0, a specificity of 0.93, and an accuracy of 0.95 when compared with arthrography; 0.89, 0.92, and 0.90, respectively, when compared with arthroscopy and arthrotomy. MR imaging could also be used effectively to evaluate tears of the intercarpal ligaments, particularly the scapholunate ligament. Disruptions of the extrinsic ligaments, articular cartilage defects, and subluxations of the distal radioulnar joint were also well demonstrated. MR imaging is an effective procedure in assessing patients with chronic wrist pain.  相似文献   
936.
In 261 infants with vomiting, 11 duodenal abnormalities were diagnosed with fluid-aided ultrasound (US). These abnormalities included duodenal obstruction, malrotation with and without associated volvulus, incomplete rotation, and duodenal stenosis. US was the initial modality used in the evaluation of vomiting in these neonates and young infants. The overall sensitivity and specificity of fluid-aided US evaluation of duodenal abnormalities were 100% and 99%, respectively. (Workup bias limits the reliability of these figures.) Fluid-aided US examination of the stomach and duodenum provided a dynamic view of duodenal rotation and anatomy, and at the very least provided a method of triaging those infants who may require surgery, upper gastrointestinal series, or follow-up US to make a definitive diagnosis.  相似文献   
937.
Common tumors of the parapharyngeal space: refined imaging diagnosis   总被引:2,自引:0,他引:2  
Som  PM; Sacher  M; Stollman  AL; Biller  HF; Lawson  W 《Radiology》1988,169(1):81-85
Computed tomographic (CT) scans and magnetic resonance (MR) images in 103 patients with either a deep-lobe parotid tumor extending into the parapharyngeal space, a minor salivary gland tumor, a neuroma, or a paraganglioma were reviewed. The parotid or extraparotid nature of these masses was established by identifying a fat plane between the mass and the parotid gland. This was more reliably accomplished with MR imaging than with CT. Although dynamic CT allowed identification of the glomus tumors, MR imaging also permitted diagnosis of these lesions. The inherent CT and MR imaging characteristics of most of the neuromas and minor salivary gland tumors were indistinguishable. However, the neuromas tended to displace the internal carotid artery anteriorly, whereas the salivary lesions displaced this vessel posteriorly. This artery was better identified on MR images than on CT scans. Thus, these lesions, which are the four most common primary parapharyngeal space tumors, can be distinguished on MR images by evaluating not only their inherent signal characteristics but also the surrounding fat planes and any displacement of the internal carotid artery.  相似文献   
938.
An efficient robust LMI‐based scheme is developed for decentralized state‐estimation of linear interconnected systems with static nonlinear interconnections and subjected to sensor nonlinearities. The interconnections satisfy quadratic constraints with manipulated parameters and the sensor nonlinearities are modeled as sector nonlinearities. The design procedure utilizes a general linear estimator structure and consists of two steps: the first giving a block‐diagonal Lyapunov matrix together with the robustness degree and the second determining the filter parameters. A numerical example is provided to illustrate the applicability of the method. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
939.
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