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1.
Discordant Electrocardiogram Left Ventricular Wall Thickness and Strain Findings in Influenza Myocarditis
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Nael Hawwa M.D. Zoran B. Popovic M.D. Ph.D. Hussain A. Isma'eel M.D. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(12):1880-1884
A 42‐year‐old man presented with a viral prodrome and tested positive for influenza A. He rapidly deteriorated developing cardiogenic shock, rhabdomyolysis, and acute kidney injury. Patient improved 1 week later with supportive measures including vasopressors, inotropes, and an intraaortic balloon pump. We report this case as it highlights the discordance between echocardiographic ventricular wall thickening as a result of myocardial edema, and electrocardiographic findings at presentation, with a reversal in findings at time of resolution. Additionally, there was some suggestion of a regional pattern to the reduced longitudinal strain. 相似文献
2.
Khaled Adil Marija Popovic Fabio L. Cury Sergio L. Faria Marie Duclos Luis Souhami 《Practical radiation oncology》2019,9(1):24-28
Purpose
This study aimed to investigate 3 planning target volume (PTV) margin expansions and determine the most appropriate volume to be used in bladder preservation therapy when using daily cone beam computed tomography (CBCT). We aimed to establish whether a smaller PTV expansion is feasible without risking geographical miss.Methods and materials
The study included patients with bladder cancer who were treated with a hypofractionated course of radiation therapy delivered with intensity modulated radiation therapy. The clinical target volume (CTV) was the whole empty bladder, and the PTV consisted of a 1.5-cm margin around the bladder (PTV1.5 cm). Patients underwent daily CBCT imaging before treatment to assess the bladder volume and ensure accurate positioning. We investigated 2 additional smaller PTV margin expansions to determine the most appropriate volume to be used with CBCT as a daily image guided radiation therapy modality. These margins were created retrospectively on every CBCT. The first additional volume was a uniform PTV margin of the surrounding 1 cm (PTV1 cm). When considering that the majority of the internal bladder movement was due to the variation in filling that occurs in the superior and anterior directions, a second volume of an anisotropic PTV margin with a 1.5-cm superior/anterior and 1 cm in other directions (PTV1/1.5 cm) was created. We recorded the frequency and measured the volume of bladder falling out of each PTV based on the daily CBCT.Results
For the purpose of this study, we considered an arbitrary 5 cm3 of CTV falling out of the designated PTV as a clinically significant volumetric miss. The frequency of such a miss when applying the uniform PTV1 cm was 1%. However, when applying the uniform PTV1.5 cm and anisotropic PTV1/1.5 cm margins, the frequency was 0.5% and 0.5%, respectively.Conclusions
The anisotropic PTV expansion of 1.5 cm superiorly and anteriorly and 1 cm in all other directions around the bladder (CTV) provides a safe PTV approach when daily CBCT imaging is used to localize an empty bladder. 相似文献3.
4.
M Engelhardt P Bast N Jeblink W Lauer A Popovic H Eufinger M Scholz A Christmann A Harders K Radermacher K Schmieder 《Minimally invasive neurosurgery》2006,49(2):98-103
This study was performed to evaluate the surgical strategy in patients with calvarial tumours, in order to design and modify a robot-assisted trepanation system. A total of 75 patients underwent craniectomy for the treatment of calvarial tumours during the 10-year period from 1993 to 2002. The patients' complaints, the size, location and histology of the tumour, and the various cranioplasty techniques used were analysed retrospectively. In a second procedure several craniectomies at typical locations according to the study's results were performed in a laboratory setting using a hexapod robotic tool, constructed at the Helmholtz-Institute, RWTH Aachen University, and plastic model heads. The workflow was documented and the reproducibility and the accuracy of the procedure were registered. A total of 83 surgical procedures were performed on 75 patients. The majority (87 %) of lesions treated surgically were located in the frontal, temporal and anterior parts of the parietal region. Histological examination revealed benign lesions in 66 % of the patients and dural involvement in 46 %. According to these results craniectomies were performed using the robotic system. Mean positioning accuracy of the robotic system while milling was 0.24 mm, with a standard deviation of 0.04 mm, and maximum error under 1 mm. Craniectomies leaving a 1-mm layer of the tabula interna intact to ensure a healthy dura were performed in several regions successfully. The majority of calvarial tumours, requiring surgical treatment in our patients, were located in cosmetically relevant areas in which drilling can be carried out with the robotic trepanation system. Consequently, the surgical approach had to be planned carefully in order to achieve a good cosmetic outcome. 相似文献
5.
Use of algal fluorescence for determination of phytotoxicity of heavy metals and pesticides as environmental pollutants 总被引:3,自引:0,他引:3
The phytotoxicity of heavy metals and pesticides was studied by using the fluorescence induction from the alga Dunaliella tertiolecta. The complementary area calculated from the variable fluorescence induction was used as a direct parameter to estimate phytotoxicity. The value of this parameter was affected when algae were treated with different concentrations of mercury, copper, atrazine, DCMU, Dutox, and Soilgard. The toxic effect of these pollutants was estimated by monitoring the decrease in the complementary area, which reflects photosystem II photochemistry. Further, the authors have demonstrated the advantage of using the complementary area as a parameter of phytotoxicity over using variable fluorescence yield. The complementary area of algal fluorescence can be used as a simple and sensitive parameter in the estimation of the phytotoxicity of polluted water. 相似文献
6.
M Popovic J Kolarovic M Mikov S Trivic B Kaurinovic 《European journal of drug metabolism and pharmacokinetics》2007,32(2):101-108
Our research was aimed at establishing if and how selenium (Se) ion, N-acetylcysteine (NAC), sodium salt of monoketocholic acid (MKH) and superoxide-dismutase (SOD), administered in the experimental animal model, could affect the possible cytotoxicity associated with anthracycline-based combined chemotherapy with doxorubicin, vincristine and prednisolone (DVP). The following biochemical parameters were investigated: the extent of lipid peroxidation (LPx), and the activity of peroxidase (Px), catalase (CAT), glutathione-peroxidase (GSHPx), and xanthine-oxidase (XOD). A statistical increase in LPx activity was obtained by SOD, MKH, DVPSe and DVPMKH. All chemotherapeutic agents reduced Px activity in a statistically significant manner. There was no statistical significance for the results regarding the effects of the administered substances on GSHPx activity. The results for DVP, SOD, MKH, DVPSOD, DVPSe and DVPMKH showed reduced XOD activity which was statistically significant, which was lowest in the case of MKH, while NAC and Se reduced the activity of this enzyme but statistically non significant. NAC, Se, DVP, MKH and DVPMKH caused a reduction in CAT activity, while DVPSOD and DVPSe caused an increase of the latter. 相似文献
7.
V. Popovic D. Micic S. Damjanovic L. Calovic Z. Rolovic A. Mijovic M. Petakov D. Manojlovic J. Micic 《Postgraduate medical journal》1992,68(805):925-927
There is experimental evidence that a portion of follicle-stimulating hormone (FSH) secretion is independent of hypothalamic influences. A 29 year old woman with familial pure gonadal dysgenesis developed myelodysplastic syndrome. Endocrine investigations showed discrepancy between serum FSH and luteinizing hormone (LH) levels. FSH levels remained elevated while LH levels decreased. The FSH to LH ratio was 10 (normal 2-2.5). The fall in LH is likely to be due to factor(s) involved directly and specifically in LH synthesis and release. Exogenous LH releasing hormone administration as well as hormonal replacement treatment increased LH levels. The FSH to LH ratio decreased to 7. This case supports the hypothesis of differential regulation of FSH and LH, and that FSH secretion is at least partly autonomous. 相似文献
8.
A D Popovic B Milovanovic A N Neskovic K Pavlovski B Putnikovic I Hadzagic 《Cardiology》1992,80(2):94-99
Transesophageal echocardiography is a new echocardiographic technique with indications that are still expanding and being redefined. Recently, the usefulness of transesophageal echocardiography in pulmonary embolism has been demonstrated in several case reports. In this article, we present 3 cases with pulmonary embolism diagnosed by transesophageal echocardiography and discuss its diagnostic value in this clinical setting. 相似文献
9.
Guarner J Jernigan JA Shieh WJ Tatti K Flannagan LM Stephens DS Popovic T Ashford DA Perkins BA Zaki SR;Inhalational Anthrax Pathology Working Group 《The American journal of pathology》2003,163(2):701-709
During October and November 2001, public health authorities investigated 11 patients with inhalational anthrax related to a bioterrorism attack in the United States. Formalin-fixed samples from 8 patients were available for pathological and immunohistochemical (IHC) study using monoclonal antibodies against the Bacillus anthracis cell wall and capsule. Prominent serosanguinous pleural effusions and hemorrhagic mediastinitis were found in 5 patients who died. Pulmonary infiltrates seen on chest radiographs corresponded to intraalveolar edema and hyaline membranes. IHC assays demonstrated abundant intra- and extracellular bacilli, bacillary fragments, and granular antigen-staining in mediastinal lymph nodes, surrounding soft tissues, and pleura. IHC staining in lung, liver, spleen, and intestine was present primarily inside blood vessels and sinusoids. Gram's staining of tissues was not consistently positive. In 3 surviving patients, IHC of pleural samples demonstrated abundant granular antigen-staining and rare bacilli while transbronchial biopsies showed granular antigen-staining in interstitial cells. In surviving patients, bacilli were not observed with gram's stains. Pathological and IHC studies of patients who died of bioterrorism-related inhalational anthrax confirmed the route of infection. IHC was indispensable for diagnosis of surviving anthrax cases. The presence of B. anthracis antigens in the pleurae could explain the prominent and persistent hemorrhagic pleural effusions. 相似文献
10.
Dejan Popovic Tessa Gordon Victor F. Rafuse Dr. Arthur Prochazka 《Annals of biomedical engineering》1991,19(3):303-316
Implanted wire electrodes are increasingly being used for the functional electrical stimulation of muscles in partially paralysed
patients, yet many of their basic characteristics are poorly understood. In this study we investigated the selectivity, recruitment
characteristics and range of control of several types of electrode in triceps surae and plantaris muscles of anaesthetized
cats. We found that nerve cuffs are more efficient and selective (i.e., cause less stimulus spread to surrounding muscles)
than intramuscular electrodes. Bipolar intramuscular stimulation was more efficient and selective than monopolar stimulation,
but only if the nerve entry point was between the electrodes. Monopolar electrodes are efficient and selective if located
close to the nerve entry point, but their performance declines with distance from it. Nonetheless, for a variety of reasons
monopolar stimulation provides the best compromise in many current applications. Short duration pulses offer the best efficiency
(least charge per pulse to elicit force) but high peak currents, increasing the risk of electrode corrosion and tissue damage.
Electrode size has little effect on recruitment and should therefore be maximised because this minimises current density. 相似文献