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991.
Due to lack of evidence from prospective clinical trials, the diagnostic procedures, their frequency, as well as the length of the follow-up period in cutaneous melanoma patients should be based on the individual risk of disease recurrence, which is strongly dependent on the stage of disease at the time of diagnosis. In the paper we propose the current recommendations for follow-up strategy. Nowadays, new effective treatment options with biological agents justify the closer monitoring of high risk melanoma patients. 相似文献
992.
Marcin G. Prost H. Jacobus Gilhuis Rolf E. Brouwer Piotr Gawda 《Case reports in ophthalmology》2014,5(3):416-422
Purpose
To report our experience in managing a case of bilateral optic disc oedema and unilateral cystoid macular oedema with a posterior subtenon (PST) injection of triamcinolone acetonide and intravitreal bevacizumab (IVB) in a patient with polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome.Case Report
A 50-year-old healthy woman complaining of bilateral blurred vision for several days was referred to the ophthalmologist. An eye examination showed a bilateral optic disc swelling and small preretinal haemorrhages. In addition, a peripheral neuropathy was found. Laboratory tests showed elevated levels of M-protein type IgA of 1.4 g/l and a vascular endothelial growth factor (VEGF) concentration of 6.1 ng/ml. The cerebrospinal fluid protein content was 131 mg/dl. An abdominal CT scan revealed hepatosplenomegaly. The diagnosis of POEMS syndrome was made based on the polyneuropathy, hepatosplenomegaly, IgA lambda monoclonal proteinemia, and optic disc swelling. As vision declined, 40 mg PST injection of triamcinolone was given bilaterally. Ten weeks thereafter, 2 IVB injections of 2.5 mg were administered to the left eye, with a 4-week interval. Because of an incomplete recovery of her visual functions, diarrhoea and general malaise, melphalan, followed by autologous peripheral blood stem cell transplantation, was initiated. After systemic treatment, she had no visual complaints anymore, the optic disc oedema had resolved, and the VEGF serum concentration had normalized.Discussion
Local treatment with IVB and PST injection of triamcinolone can be an option for ocular symptoms in POEMS syndrome. However, given the incomplete recovery of the ocular abnormalities and the other symptoms, systemic treatment remains standard.Key words: POEMS syndrome, Optic disc oedema, Macular oedema, Bevacizumab, Triamcinolone 相似文献993.
Ewa Majchrzak Bartosz Szybiak Anna Wegner Piotr Pienkowski Jakub Pazdrowski Lukasz Luczewski Marcin Sowka Pawel Golusinski Julian Malicki Wojciech Golusinski 《Radiology and oncology》2014,48(1):1-10
Background
Head and neck squamous cell carcinoma (HNSCC) is a disease of middle-aged to elderly adults. However, an increased incidence of HNSCC in young people under 45 years of age has been reported recently. In the present review, we focused on the epidemiology and aetiology of HNSCC in adults under 45 years of age.Methods
We reviewed literature related to HNSCC in adult patients less than 45 years of age and discussed current treatment options and prognosis.Results
HNSCC in young adults is associated with a higher incidence rate in nonsmokers, lower female-to-male ratio, a higher percentage of oral cavity and oropharynx tumours, and fewer second primary tumours. However, aside from traditional risk factors of tobacco and alcohol exposure, the causes of these cancers in young adults remain unclear. Agents that might contribute to risk include infection with high-risk human papillomavirus subtypes as well as genetic factors or immunodeficiency status. The expected increase in incidence and mortality of the young with HNSCC may become a major public health concern if current trends persist, particularly lifestyle habits that may contribute to this disease.Conclusions
Given the younger age and potential long-term adverse sequelae of traditional HNSCC treatments, young adults should be treated on a case-by-case basis and post-therapy quality of life must be considered in any treatment-decision making process. 相似文献994.
Adam Staron Manish Bansal Piyush Kalakoti Ayumi Nakabo Zbigniew Gasior Piotr Pysz Krystian Wita Marek Jasinski Partho P. Sengupta 《The international journal of cardiovascular imaging》2013,29(4):797-808
Regression of left ventricular (LV) mass in severe aortic stenosis (AS) following aortic valve replacement (AVR) reduces the potential risk of sudden death and congestive heart failure associated with LV hypertrophy. We investigated whether abnormalities of resting LV deformation in severe AS can predict the lack of regression of LV mass following AVR. Two-dimensional speckle tracking echocardiography (STE) was performed in a total of 100 subjects including 60 consecutive patients with severe AS having normal LV ejection fraction (EF > 50 %) and 40 controls. STE was performed preoperatively and at 4 months following AVR, including longitudinal strain assessed from the apical 4-chamber and 2-chamber views and the circumferential and rotational mechanics measured from the apical short axis view. In comparison with controls, the patients with AS showed a significantly lower LV longitudinal (p < 0.001) and circumferential strain (p < 0.05) and higher apical rotation (p < 0.001). Following AVR, a significant improvement was seen in both strains (p < 0.001 for each respectively), however, apical rotation remained unchanged (p = 0.14). On multivariate analysis, baseline LV mass (odds ratio 1.02; p = 0.011), left atrial volume (odds ratio 0.81; p = 0.048) and circumferential strain (odds ratio 0.84; p = 0.02) independently predicted LV mass regression (>10 %) following AVR. In conclusion, STE can quantify the burden of myocardial dysfunction in patients with severe AS despite the presence of normal LV ejection fraction. Furthermore, resting abnormalities in circumferential strain at LV apex is related with a hemodynamic milieu associated with the lack of LV mass regression during short-term follow up after AVR. 相似文献
995.
Robert Panowicz Marcin Konarzewski Tomasz Durejko Mateusz Szala Magdalena aziska Magdalena Czerwiska Piotr Prasua 《Materials》2021,14(14)
The influence of the thermo-oxidative aging semi-crystalline polyethylene terephthalate process on the thermal and mechanical properties was analysed in the article. For this purpose, PET was aged at 140 °C for 21, 35 and 56 days. The research showed that as a result of aging, the amount of the crystalline phase increases by about 8%, which translates into the properties of the aged material. The glass transition and melt temperature of lamellar crystals formed during first and second crystallisation increase with aging. The mechanical properties of the material were analysed in the temperature range of 25 to 75 °C. The tests were showing an increase in Young’s modulus and a decrease in elongation at the break as a result of aging. This phenomenon was particularly visible during tests at 75 °C and during the morphological observation of the fracture surface, where the fracture character of the material changes from ductile to brittle. In the case of the material aged for the longest time, the temperature has a negligible influence on the elongation at break. 相似文献
996.
Kölsch H Jessen F Wiltfang J Lewczuk P Dichgans M Kornhuber J Frölich L Heuser I Peters O Schulz JB Schwab SG Maier W 《Neuroscience letters》2008,440(1):68-71
SORL1 gene variants were described as risk factors of Alzheimer's disease (AD). We investigated the association of four SORL1 variants with CSF levels of Abeta42 and Abeta40 in 153 AD patients recruited from a multicenter study of the German Competence Net Dementias. Only one SORL1 SNP was associated with altered Abeta42 levels in the single marker analysis (SNP21: p=0.011), the other SNPs did not show an association with Abeta42 or Abeta40 CSF levels. Haplotype analysis identified a three marker SORL1 haplotype consisting of SNP19 T-allele, SNP21 G-allele and SNP23 A-allele (T/G/A) which was associated with reduced Abeta42 CSF levels in AD patients (p=0.003). Abeta40 levels were also lower in carriers of this haplotype; however, this did not reach statistical significance (p=0.15). We found a SORL1 haplotype which was associated with CSF levels of amyloid-beta cleavage products, measured as altered levels of Abeta42. Thus our data suggest that SORL1 gene variants might influence AD pathology. 相似文献
997.
We have developed an independent algorithm for the prediction of electronic portal imaging device (EPID) response. The algorithm uses a set of images [open beam, closed multileaf collimator (MLC), various fence and modified sweeping gap patterns] to separately characterize the primary and head-scatter contributions to EPID response. It also characterizes the relevant dosimetric properties of the MLC: Transmission, dosimetric gap, MLC scatter [P. Zygmansky et al., J. Appl. Clin. Med. Phys. 8(4) (2007)], inter-leaf leakage, and tongue and groove [F. Lorenz et al., Phys. Med. Biol. 52, 5985-5999 (2007)]. The primary radiation is modeled with a single Gaussian distribution defined at the target position, while the head-scatter radiation is modeled with a triple Gaussian distribution defined downstream of the target. The distances between the target and the head-scatter source, jaws, and MLC are model parameters. The scatter associated with the EPID is implicit in the model. Open beam images are predicted to within 1% of the maximum value across the image. Other MLC test patterns and intensity-modulated radiation therapy fluences are predicted to within 1.5% of the maximum value. The presented method was applied to the Varian aS500 EPID but is designed to work with any planar detector with sufficient spatial resolution. 相似文献
998.
Objectives
Therapeutic hypothermia improves survival and neurological outcome in patients successfully resuscitated after cardiac arrest. Accurate temperature control during cooling is essential to prevent cooling-related side effects.Methods
Prospective observational study of 12 patients assessed during therapeutic hypothermia (32-34 °C) achieved by intravascular cooling following cardiac arrest. Simultaneous temperature measurements were taken using a Swan-Ganz catheter (blood temperature BLT), nasopharyngeal probe (nasopharyngeal temperature NPT) and the urinary bladder catheter (urinary bladder temperature UBT). A total of 1728 measurements (144 measurements per patient) were recorded over a 48-h period and analyzed. Blood temperature was considered as the reference measurement.Results
Temperature profiles obtained from BLT, NPT and UBT compared with the use of analysis of variance did not differ significantly. Pearson correlation revealed that the correlation between BLT and NPT as well as BLT and UBT was statistically significant (r = 0.96, p < 0.001 and r = 0.95, p < 0.001, respectively). Bland-Altman analysis proved that the agreement between all measurements was satisfactory and the differences were not clinically important.Conclusions
In 12 post-cardiac arrest patients undergoing intravascular cooling, both nasopharyngeal and urinary bladder temperature measurements were similar to blood temperatures measured using a pulmonary artery catheter. 相似文献999.
1000.
Phalangeal quantitative ultrasound measurements in chronic hemodialysis patients: a 4-year follow-up
Zywiec J Pluskiewicz W Adamczyk P Skubala A Gumprecht J 《Ultrasound in medicine & biology》2012,38(6):962-971
In the course of chronic kidney disease, bone metabolism disturbances occur and become aggravated simultaneously with the progression of renal disorder, worsening patients' quality of life. We conducted a 4-year follow-up to assess phalangeal quantitative ultrasound (QUS) measurements in 32 patients undergoing chronic hemodialysis (17 males and 15 females) whose mean ages were 56.3 ± 15.2 years. The QUSs of hand phalanges were performed using DBM 1200 (IGEA, Carpi, Italy) and are expressed as amplitude-dependent speed of sound (Ad-SoS), Z-scores, and T-scores. In comparison with the age-, sex-, and body mass index-adjusted control group, QUS parameters were significantly decreased in all patients undergoing dialysis. During the 4-year follow-up, Ad-SoS and T-scores in all study groups sloped significantly with time. The significant negative relationships between follow-up Ad-SoS results and both baseline and follow-up parathormone values were demonstrated. Our results confirm a high prevalence of bone disturbances in patients undergoing chronic hemodialysis, and they do not improve during renal replacement therapy. The parathormone level seems to be an important agent in influencing bone status, but further studies are needed to understand the other risk factors in kidney-related bone disease. 相似文献