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1.

Thromboembolic complications are the most reported cause of death in coronavirus disease-2019 (COVID-19). Hypercoagulability, platelets activation and endotheliopathy are well-recognized features in COVID-19 patients. The aim of this work was to evaluate circulating soluble selectins P, E and L at the time of hospital admission as predictors for upcoming thrombosis. This retrospective study included 103 hospitalized COVID-19 patients and 50 healthy volunteer controls. COVID-19 patients were categorized into two groups; group 1 who developed thrombosis during hospitalization and group 2 who did not. Soluble selectins were quantitated using ELISA technique. Higher levels of sP-selectin, sE-selectin and sL-selectin were detected in COVID-19 patients compared to controls. Furthermore, significantly higher levels were found in group 1 compared to group 2. Their means were [5.86 ± 1.72 ng/mL vs. 2.51 ± 0.81 ng/mL]; [50 ± 8.57 ng/mL vs. 23.96 ± 6.31 ng/mL] and [4.66 ± 0.83 ng/mL vs. 2.95 ± 0.66 ng/mL] for sP-selectin, sE-selectin and sL-selectin respectively. The elevated selectins correlated with the currently used laboratory biomarkers of disease severity. After adjustment of other factors, sP-selectin, sE-selectin and sL-selectin were independent predictors for thrombosis. At sP-selectin ≥ 3.2 ng/mL, sE-selectin ≥ 32.5 ng/mL and sL-selectin ≥ 3.6 ng/mL thrombosis could be predicted with 97.1%, 97.6% and 96.5% sensitivity. A panel of the three selectins provided 100% clinical sensitivity. Admission levels of circulating soluble selectins P, E and L can predict thrombosis in COVID-19 patients and could be used to identify patients who need prophylactic anticoagulants. E-selectin showed a superior clinical performance, as thrombo-inflammation biomarker, to the most commonly studied P-selectin.

  相似文献   
2.
Neurological Sciences - Multiple sclerosis (MS) is a chronic inflammatory neurodegenerative disease of the central nervous system. Vasoactive and intestinal peptide (VIP) and pituitary adenylate...  相似文献   
3.

PURPOSE

Porcelain fused to metal (PFM) crowns provide the best treatment option for teeth that have a large or defective restoration. More than 20% of teeth with PFM crowns or bridges require non-surgical root canal treatment (NSRCT). This may be due to the effect of restorative procedures and the possible leakage of bacteria and or their by-products, which leads to the demise of the tooth pulp. Thus, this study was planned to compare the ability of the restorative materials to seal perforated PFM specimens.

MATERIALS AND METHODS

The study evaluates the ability of amalgam, composite or compomer restorative materials to close perforated PFM specimen''s in-vitro. Ninety PFM specimens were constructed using Ni-Cr alloys and feldspathic porcelain, and then they were divided into 3 groups: amalgam (A), composite + Exite adhesive bond (B) and compomer + Syntac adhesive bond (C). All the PFM samples were embedded in an acrylic block to provide complete sealing of the hole from the bottom side. After the aging period, each group was further divided into 3 equal subgroups according to the thermocycling period (one week for 70 cycles, one month for 300 cycles and three months for 900 cycles). Each subgroup was put into containers containing dye (Pelikan INK), one maintained at 5℃ and the other at 55℃, each cycle for 30 sec time. The data obtained was analyzed by SPSS, 2006 using one way ANOVA test and student t-test and significant difference level at (P<.01).

RESULTS

The depth of dye penetration was measured at the interfaces of PFM and filling materials using Co-ordinate Vernier Microscope. The lowest levels of the dye penetration for the three groups, as well as subgroups were during the first week. The values of dye leakage had significantly increased by time intervals in subgroups A and C.

CONCLUSION

It was seen that amalgam showed higher leakage than composite while compomer showed the lowest level of leakage.  相似文献   
4.
Most studies have examined pacing strategies with cyclical activities (running and cycling). It has been demonstrated that males employ different pacing strategies during repeated maximal voluntary contractions (MVCs) dependent upon a known endpoint. Since different fatiguing mechanisms have been identified between the genders, it is not known if females use comparable pacing strategies. The purpose of this study was to examine if informing female subjects regarding the number of MVCs to perform would affect force and electromyography (EMG). Twenty well-trained females completed 3 fatiguing protocols in a randomized order. In the control condition participants were informed they would perform twelve MVCs and then actually completed twelve. In the unknown condition they were not told how many MVCs to perform but were stopped after twelve. In the deception condition they were initially informed to perform 6 MVCs, but after the 6th MVC they were asked to perform a few more MVCs and were stopped after twelve. During the first 6 MVCs, forces in the deception condition were greater compared to the unknown (p = 0.021, ES = 0.65, 5%) and control (p = 0.022, ES = 0.42, 3%) conditions. No differences were found between conditions in the last 6 MVCs. A main effect for repetitions showed force deficits during the first 6 MVCs (p = 0.000, ES = 1.81, 13%) and last 6 MVCs (p = 0.05, ES = 0.34, 3%). No differences were found between conditions in biceps and triceps EMG. However, EMG decreased during the first 6 MVCs for biceps (p = 0.001, ES = 1.0, 14%) and triceps (p = 0.001, ES = 0.76, 14%) across conditions. No differences were found in the last 6 MVCs. The anticipation of performing fewer MVCs led to increased force, whereas no endpoint led to decreased force production.

Key points

  • Pacing strategies occur during repeated (fatiguing) MVCs as a function of end point expectations.
  • Females use similar pacing strategies as previously published results with males.
  • Without a known end point, females will tend to pace themselves by decreasing force output even when asked to perform maximal contractions.
Key words: Fatigue, electromyography, deception, pacing  相似文献   
5.
Immunotherapy has evolved considerably in the last decade and is becoming an integral component of the armamentarium for the treatment of patients with advanced solid tumors. It is important for clinicians, especially surgeons, to understand the basic principles of novel immunotherapies and the immune system. This review summarizes the evolution of the most relevant immunotherapies, their mechanisms of action, the data supporting their clinical use, and integration of immunotherapy into multidisciplinary management of solid tumors. This review should serve as a primer for clinicians and surgeons to understand the rapidly evolving field of immunotherapy.  相似文献   
6.
7.
Cystic dystrophy of the duodenal wall is a rare benign disease characterized by development of multiple cysts in heterotopic pancreatic tissue in the duodenal wall. A forty-five-year-old male came to the emergency department of our hospital complaining of severe abdominal pain and vomiting. Computerized tomography (CT) scan of the chest, abdomen and pelvis had been done. The patient was treated by pancreaticoduodenectomy.  相似文献   
8.
Introduction. Pancreas cancer is the fourth commonest cause of cancer-related mortality across the world, with incidence equalling mortality. A recent study has suggested that both the incidence and the mortality of pancreatic cancer are falling in the UK. We investigated whether this trend was being seen all over the world. Methods. Age-standardized mortality (world) rates [ASR(W)] for pancreatic cancer were extracted separately for males and females from a database maintained by the International Agency for Research on Cancer for 51 countries across the world (Europe, 33 countries; Americas, 8 countries; and Asia, 10 countries) for the period 1992–2002; log-linear regression analysis was performed to analyse trends in the past decade. Results. In the period 1992–2002, the ASR(W) remained static across most countries for both sexes. The highest mortality rates (for both sexes) were seen in Central Europe [range: men (8–12), women (4.5–7)] with trends towards increasing mortality in Romania (p<0.001), along with Albania, Spain and Croatia (p<0.01). Korea in the Far East, too, demonstrated increasing mortality trends for both sexes (men p<0.001, women p<0.01). Increasing mortality trends were also observed among women in France (p<0.001). In Canada, there was a decline in mortality [men (7.5–6.4), women (5.9–5); p<0.01], while for men there was a downward trend in Ireland, the UK, Switzerland, Austria, and Poland [p<0.05]. Conclusion. The changes perhaps reflect standardization and consolidation of diagnostic tests for pancreatic cancer in the Western world and further in-depth analysis would be required.  相似文献   
9.
Plasmablastic lymphoma (PBL) is a unique type of diffuse proliferation of large neoplastic lymphoid cells most of which resemble B immunoblasts, but all tumor cells show the immunophenotype of plasma cells. It has a strong predilection for jaw and oral cavity in HIV-positive patients. Incidences of extraoral location of this tumor is increasingly being recognized especially in HIV-negative patients for example, stomach, jejunum, omentum, anorectum, lungs, testes, soft tissues, lymph nodes, bone marrow, skin, and central nervous system. We present a case of PBL found in cecum in an HIV-negative patient. It was accompanied by lung and lymph node involvement and presented as abdominal mass. This is only the second reported case of PBL originating in cecum.  相似文献   
10.
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