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81.
Tariq S. Marroush Andrew R. Boshara Bassent Botros Philip Vendittelli Zohaib Ahmed Luay Dawood Howard S. Rosman 《Heart & lung : the journal of critical care》2018,47(2):131-135
Background
The rupture of sinus of Valsalva aneurysm (RSoVA) is a rare disorder that affects the integrity of the cardiovascular system, disrupting its dynamics and resulting in a variety of manifestations. In this report, we discuss two cases of RSoVA that we encountered and review similar cases reported in the literature.Methods
literature review of reported cases of RSoVA in PubMed and Google Scholar.Results
A total of 223 cases were found and the final analysis included 225 cases, of which 69% occurred in males and the mean age was 38.9 years.Dyspnea was the most common presenting symptom and 76% of the cases described continuous murmur on examination. The right sinus was affected in 61% of the cases and the fistula connected to the right chambers of the heart 73% of the time.Conclusion
RSoVA is a rare condition that is difficult to diagnose, it should be considered in the right context, particularly in young patients with symptoms of heart failure and the presence of continuous murmur on cardiac examination. 相似文献82.
The depletion of fossil fuels and associated environmental problems have drawn our attention to renewable energy resources in order to meet the global energy demand. Electrocatalytic hydrogen evolution has been considered a potential energy solution due of its high energy density and environment friendly technology. Herein, we have successfully synthesized a noble-metal-free Co–Ni/MoS2 nanocomposite for enhanced electrocatalytic hydrogen evolution. The nanocomposite has been well characterized using HRTEM, elemental mapping, XRD, and XPS analysis. The as-synthesized nanocomposite exhibits a much smaller onset potential and better current density than those of Co–MoS2, Ni–MoS2 and MoS2, with a Tafel value of 49 mV dec−1, which is comparable to that of a commercial Pt/C catalyst. The synergistic effect and interfacial interaction of Co–Ni bimetallic nanoparticles enhances the intrinsic modulation in the electronic structure resulting in an improved HER performance. Moreover, the electrochemical impedance spectroscopic results suggest smaller resistance values for the Co–Ni/MoS2 nanocomposite, compared to those for the charge transfer of bare nanosheets, which increase the faradaic process and in turn enhance the HER kinetics for a better performance. Our as-synthesized Co–Ni/MoS2 nanocomposite holds great potential for the future synthesis of noble-metal-free catalysts.A noble-metal-free Co–Ni/MoS2 nanocomposite was synthesized, which showed enhanced electrocatalytic hydrogen evolution performance. 相似文献
83.
Jung Suk Kim Jong Hyuck Park Sung Chan Jeong Dong Shik Kim Abid Mehmood Yousaf Fakhar Ud Din 《Journal of microencapsulation》2013,30(5):421-427
AbstractTo develop a novel revaprazan-loaded gelatine microsphere with enhanced solubility and oral bioavailability, numerous gelatine microspheres were prepared using a spray-drying technique. The impact of gelatine amount on drug solubility in the gelatine microspheres was investigated. The physicochemical properties of the selected gelatine microsphere, such as shape, particle size and crystallinity, were evaluated. Moreover, its dissolution and pharmacokinetics in rats were assessed in comparison with revaprazan powder. Amongst the gelatine microspheres tested, the gelatine microsphere consisting of revaprazan and gelatine (1:2, w/w), which gave about 150-fold increased solubility, had the most enhanced drug solubility. It provided a spherical shape, amorphous drug and reduced particle size. Furthermore, it gave a higher dissolution rate and plasma concentration than did revaprazan powder. Particularly, it gave about 2.3-fold improved oral bioavailability in comparison with revaprazan powder. Therefore, this novel gelatine microsphere system is recommended as an oral pharmaceutical product of poorly water-soluble revaprazan. 相似文献
84.
Barone GW Wright CF Krause MW Brosnahan GM Portilla D Banerjee S McCowan TC Culp WC Yousaf M 《American journal of surgery》2007,194(5):668-671
BACKGROUND: Publication of the Kidney Disease Outcomes Quality Initiative (KDOQI) Guidelines has reinforced an already increased focus within the Veterans Health Administration (VHA) on arteriovenous (AV) hemodialysis (HD) vascular access. Meeting these KDOQI goals has been the responsibility of individual VHA centers. We responded by organizing a dedicated HD AV clinic to provide preoperative evaluation and postoperative follow-up. METHODS: The records of 130 patients referred from January 2004 through June 2006 to our AV HD clinic were retrospectively reviewed. A minimum of 6 months of postoperative follow-up was required. RESULTS: AV fistulae were performed in 71% of the patients, with approximately 45% being Brescia-Cimino fistulae. Importantly, only 38% of AV fistulae matured and were used without secondary intervention. The remaining 62% of AV fistulae each required 2.2 +/- .3 interventions. The final AV fistula use rate was approximately 85%. CONCLUSIONS: To meet these KDOQI guidelines, the VHA should continue to support the concept of dedicated AV HD teams and clinics. This is essential because the majority of our new AV fistulae required secondary intervention for AV fistulae maturation and use. A dedicated HD access team should better be able to assess AV fistula maturation and organize subsequent intervention to promote AV fistulae use. 相似文献
85.
Purpose
Colon cancer is more common in the elderly than in younger and middle-aged people. Cancer clinical trials focus more on younger patients and the management of elderly patients with advanced disease is still unclear. 相似文献86.
Rahim MK Durr-E-Sabih Mateen A Najam-Uddin Yousaf M 《Nuclear medicine communications》2007,28(11):852-858
PURPOSE: To assess the gastric emptying pattern of a standardized solid meal in patients with non-ulcer dyspepsia by using scintigraphic techniques. METHODS: Results for the half-emptying time for solids (T1/2) and percent clearance of solid meal at 60 min (C60) of patients (n=35) having non-ulcer dyspepsia according to Rome II criteria were compared with age- and sex-matched controls (n=28). Gastric emptying was studied by using egg omelette labelled with Tc tin colloid. Data acquisition was done using two protocols: dynamic acquisition was performed for the first 100 min and then static acquisition was carried out for up to 4 h. T1/2 and C60 were calculated from the computer-generated time-activity curve. RESULTS: The normal range of T1/2 was 29-88 min (mean+/-2 SD) among the control group. The mean T1/2 of the patient group was 160.1+/-96.1 min (P<0.01). Twelve of 22 male patients and 11 of 13 female patients had prolonged T1/2. The normal range of C60 was 92-28% (mean+/-2 SD) in the control group. The mean C60 of the patient group was 33.1+/-18.5% (P<0.01). Fifteen of 22 male patients and 11 of 13 female patients had shortened C60. CONCLUSION: Gastric emptying is significantly delayed in both men and women having non-ulcer dyspepsia as the T1/2 is prolonged and the C60 is shortened in a significant number of these patients. Radionuclide tests might offer an objective way of assessing this particular aspect of gastric physiology. 相似文献
87.
Compared to the general population, the suicide risk among Danish cancer patients diagnosed in 1971-1986 was increased by 50% for men and 30% for women. We updated the earlier study to evaluate both long-term and recent trends in the suicide risk. Cancer patients with a first cancer diagnosed between 1971 and 1999 in Denmark were followed-up for completed suicide through 1999. Excluding nonmelanoma skin cancer, 564 508 cancer patients were included and 1241 suicides observed. Both the standardised mortality ratio (SMR) of suicide relative to the general population and the suicide rates were analysed with Poisson regression methods. The overall SMR was increased to 1.7 (95% CI. 1.6-1.9) for men and 1.4 (95% CI: 1.3-1.5) for women. Following the cancer diagnosis, the suicide risk was highest in the first 3 months for men and between months 3 and 12 for women. The risk was higher for nonlocalized cancer and for cancers with perceived poor prognosis. Breast cancer patients had a higher risk than other cancer patients with similar good prognosis. The suicide rates among cancer patients decreased with calendar time, but less so than the rates in the general population. The suicide risk among cancer patients has not decreased as much as in the Danish population and reasons for this should be explored. Breast cancer might be believed by patients to be more life threatening than it is. Assessment and treatment of depression could improve the quality of life for cancer patients who suffer from unrecognised depressions and in turn reduce the risk of suicide in cancer patients. 相似文献
88.
A case of recurrent intracranial abscess at the initial site after a latency of 16 years is presented. The causes and possible mechanisms of recurrence are discussed. 相似文献
89.
BACKGROUND: This study was conducted to estimate the neonatal tetanus (NNT) mortality rate and to identify the risk factors for NNT deaths in Loralai District, Pakistan. METHOD: We conducted a community-based cross-sectional survey during July-September 1997. We stratified the sample proportionate to population of union councils. The most populous village in a union council was selected first. We interviewed the women, selected randomly, who had a live birth in the 18 months preceding the survey. We conducted a matched case-control study to identify the risk factors for NNT deaths. We used the World Health Organization criteria to enrol cases, identified during the cross-sectional survey or registered at the district hospital. We enrolled three community-based controls per case, matched on the area of residence, immunization status and date of birth. RESULTS: Of the 1547 live births, there were 36 neonatal deaths due to tetanus. The NNT mortality rate in the district was 23 per 1000 live births (95% CI: 16-30). For the case-control study, we enrolled 41 cases and 123 controls. Using conditional logistic regression, the risk of NNT death was increased with the use of soil as delivery surface (O.R = 3.2, 95% CI: 1.1-10.2), father's illiteracy (OR = 3.2, 95% CI: 1.3-8.1) and possession of sheep at home (OR = 2, 95% CI: 1.0-5.0). The population attributable risk per cent for soil as delivery surface was 64%. CONCLUSION: Transmission of infection while using soil as the delivery surface can occur through direct or indirect contamination of the fresh umbilical wound. Use of safer delivery practices in general and clean surfaces in particular should be encouraged to reduce the NNT mortality rate in the area. 相似文献
90.
Studies in cobra venom factor treated rats of antibody coated erythrocyte clearance by the spleen: differential influence of red blood cell antigen number on the inhibitory effects of immune complexes on Fc dependent clearance 总被引:1,自引:1,他引:1
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The splenic component of the mononuclear phagocyte system (MPS) was investigated in decomplemented rats by determining the clearance from the blood of erythrocytes coated with a monoclonal antibody (R3/13). The infusion of immune complexes (IC), prepared at 10-fold antigen excess, at an appropriate time during the erythrocyte clearance produced a significant increase in the T1/2 of the antibody coated cells. Immune complexes formed with the F(ab')2 fragment of the rabbit antibody did not have any significant effect. A positive correlation was seen between the dose of immune complex infused and the degree of inhibition of erythrocyte clearance. The influence of red cell antigen number on the behaviour of erythrocytes sensitized with R3/13 was studied by comparing the clearance of DA and (DA X PVG) F1 erythrocytes. F1 erythrocytes, with only half the number of specific antigens on their surface that bind R3/13 antibody were cleared much more slowly (82 +/- 2.6 min, mean +/- s.e.) by the spleen than the DA erythrocytes (44 +/- 1.5 min P less than 0.001). Both cell suspensions were equally susceptible to inhibition by soluble IC. These studies show that the number of specific antigens on the red cell surface influences the rate at which sensitized cells are removed by splenic macrophage Fc receptors but not their susceptibility to inhibition by IC. Our results draw attention to a major defect in the use of autologous erythrocytes coated with anti-rhesus (D) immunoglobulin to assess macrophage Fc receptor function in man. 相似文献