The author proposes a typology for the case study following a definition wherein various layers of classificatory principle are disaggregated. First, a clear distinction is drawn between two parts: ...(1) the subject of the study, which is the case itself, and (2) the object, which is the analytical frame or theory through which the subject is viewed and which the subject explicates. Beyond this distinction the case study is presented as classifiable by its purposes and the approaches adopted— principally with a distinction drawn between theory-centered and illustrative study. Beyond this, there are distinctions to be drawn among various operational structures that concern comparative versus noncomparative versions of the form and the ways that the study may employ time. The typology reveals that there are numerous valid permutations of these dimensions and many trajectories, therefore, open to the case inquirer.
Furin catalyses a simple biochemical reaction--the proteolytic maturation of proprotein substrates in the secretory pathway. But the simplicity of this reaction belies furin's broad and important ...roles in homeostasis, as well as in diseases ranging from Alzheimer's disease and cancer to anthrax and Ebola fever. This review summarizes various features of furin--its structural and enzymatic properties, intracellular localization, trafficking, substrates, and roles in vivo.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Patients with testicular germ cell tumors (TGCT) have an increased risk for venous thromboembolism (VTE). We identified risk factors for VTE in this patient cohort and developed a clinical risk ...model.
In this retrospective cohort study at the Medical University of Graz we included 657 consecutive TGCT patients across all clinical stages. A predictive model for VTE was developed and externally validated in 349 TGCT patients treated at the University Hospital Zurich.
Venous thromboembolic events occurred in 34 (5.2%) patients in the Graz cohort. In univariable competing risk analysis, higher clinical stage (cS) and a retroperitoneal lymphadenopathy (RPLN) were the strongest predictors of VTE (p<0.0001). As the presence of a RPLN with more than 5cm in greatest dimension without coexisting visceral metastases is classified as cS IIC, we constructed an empirical VTE risk model with the following four categories (12-month-cumulative incidence): cS IA-B 8/463 patients (1.7%), cS IS-IIB 5/86 patients (5.9%), cS IIC 3/21 patients (14.3%) and cS IIIA-C 15/70 patients (21.4%). This risk model was externally validated in the Zurich cohort (12-month-cumulative incidence): cS IA-B (0.5%), cS IS-IIB (6.0%), cS IIC (11.1%) and cS IIIA-C (19.1%). Our model had a significantly higher discriminatory performance than a previously published classifier (RPLN-VTE-risk-classifier) which is based on the size of RPLN alone (AUC-ROC: 0.75 vs. 0.63, p = 0.007).
According to our risk stratification, TGCT patients with cS IIC and cS III disease have a very high risk of VTE and may benefit from primary thromboprophylaxis for the duration of chemotherapy.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this essay, Gary Thomas argues that education research repeatedly makes a mistake first noted by Dewey: it misunderstands our science. This misunderstanding has led to attempts to import various ...putatively scientific precepts into education inquiry. But in reality, he argues, those "scientific" precepts do not characterize scientific endeavor, which is fluid and plural: science flexes to any angle to answer the questions that are posed in any field. Questions in education concern worlds of practice and social relations where change and corrigibility draw the parameters for inquiry. Education research becomes valuable only when it takes account of the reality of the educational endeavor. Thomas urges us to strive to forge a new science of education based on singular and shared understandings of such practice. (Contains 10 notes, 1 table, and 2 figures.)
This accessible guide takes you through the process of designing, conducting and writing up a research project using case study methods. In his characteristic warm and friendly style, Gary Thomas ...covers each step at a confidence-building pace, helping you to get to grips with the theory and practice of doing a case study. Focusing on vital issues like validity, reliability and quality in research, the author helps you ensure your research is rigorous and methodologically sound. This third edition: Offers an expanded discussion of key ethical issues in case study research Provides up to date information about using social media in research Presents a new navigation tool to help you plan your case study project Enables you to develop the skills you need to become a critical and reflexive researcher Covering international examples of case study in practice and accompanied by downloadable checklists and templates, this book is the perfect companion to help you successfully complete a case study.
Cancer is an independent risk factor for the development of venous thromboembolism (VTE). Glioblastomas are amongst cancer types with the most thrombogenic potential and patients are at a ...particularly high risk of VTE with an incidence up to 20-30% per year. Currently, major efforts are underway to gain novel insights into risk factors and pathomechanisms to provide a better understanding of development of VTE in patients with primary brain tumors. Treatment of VTE requires therapeutic anticoagulation, which accordingly to recently-published guidelines should be performed using low molecular weight heparin or, in case of low bleeding risk, using a direct oral anticoagulant. However, this can be very challenging due to an increased risk of intracranial hemorrhage in this patient group. Furthermore, limited data are available on the subgroup of patients with primary brain tumors.
Platelet-to-Lymphocyte Ratio (PLR) is an easily applicable blood test. An elevated PLR has been associated with poor prognosis in patients with different oncologic disorder. As platelets play a key ...role in atherosclerosis and atherothrombosis, we investigated PLR and its association with critical limb ischemia (CLI) and other vascular endpoints in peripheral arterial occlusive disease (PAOD) patients.
We evaluated 2121 PAOD patients treated at our institution from 2005 to 2010. PLR was calculated and the cohort was categorized into tertiles according to the PLR. An optimal cut-off value for the continuous PLR was calculated by applying a receiver operating curve analysis to discriminate between CLI and non-CLI. In our cohort occurrence of CLI significantly increased with an increase in PLR. As an optimal cut-off value, a PLR of 150 was identified. Two groups were categorized, one containing 1228 patients (PLR≤150) and a second group with 893 patients (PLR>150). CLI was more frequent in PLR>150 patients (410(45.9%)) compared to PLR≤150 patients (270(22.0%)) (p<0.001), as was prior myocardial infarction (51(5.7%) vs. 42(3.5%), p = 0.02). Regarding inflammatory parameters, C-reactive protein (median 7.0 mg/l (3.0-24.25) vs. median 5.0 mg/l (2.0-10.0)) and fibrinogen (median 457 mg/dl (359.0-583.0) vs. 372 mg/dl (317.25-455.75)) also significantly differed in the two patient groups (both p<0.001). Finally, a PLR>150 was associated with an OR of 1.9 (95%CI 1.7-2.1) for CLI even after adjustment for other well-established vascular risk factors.
An increased PLR is significantly associated with patients at high risk for CLI and other cardiovascular endpoints. The PLR is a broadly available and cheap marker, which could be used to highlight patients at high risk for vascular endpoints.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Haemoglobin concentration was 10·8 g/dL (normal 12·0–15·3); microcytic–hypochromic red blood cell indices, a low ferritin concentration of 12 ng/mL (normal 22–112), and a soluble transferrin receptor ...concentration of 10·1 mg/L (normal 1·78–4·59) indicated an iron deficiency anaemia. A thrombophilia screen—including resistance to activated protein C, and protein C and protein S activity—was negative; no antibodies to platelet factor 4 were found and genetic testing for prothrombin mutations was negative. Tests for hantaviruses, HIV, hepatitis B virus, hepatitis C virus, and antiphospholipid antibodies (cardiolipin, β2 glycoprotein, and lupus) were negative.
Updated PMC trends derived from SBUV data DeLand, Matthew T.; Thomas, Gary E.
Journal of geophysical research. Atmospheres,
16 March 2015, Letnik:
120, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Previous analysis of polar mesospheric clouds (PMCs) observed by Solar Backscatter Ultraviolet (SBUV) instruments found that long‐term variations in PMC brightness and occurrence frequency were ...anticorrelated with solar activity and that an increasing secular trend was present at most latitudes. In this paper, long‐term PMC variations are presented in terms of ice water content (IWC), a physically based variable which is easier to interpret than previously reported UV albedo values. This model‐based conversion from albedo to IWC removes most scattering angle effects. The derived long‐term PMC variations in the SBUV data set are qualitatively the same using either an empirically derived adjustment for local time effects or no adjustment (i.e., assuming cancelation of interannual variations in tidally induced amplitude and/or phase). When we use stratospheric ozone variations as a proxy for mesospheric temperature changes, as suggested by recent model studies, we can explain more of the long‐term IWC variability than if we use a linear trend. These results show that PMC ice water content in bright clouds increased rapidly from 1979 through the late 1990s and has been approximately constant from the late 1990s through 2013. The numerical value and sign of this trend during the last 15 years depend on the choice of end points and latitude band. Simultaneously, the solar response of IWC observed by SBUV has weakened during the most recent cycle in the Northern Hemisphere, but increased in the Southern Hemisphere.
Key Points
SBUV instruments have observed long‐term changes in PMCs since 1978
Expressing PMC behavior in terms of ice water content reduces local time effects
PMC trends in IWC have been significantly flatter since the late 1990s
On examination she was afebrile, her peripheral oxygen saturation was 98% (fraction of inspired O2 21%), blood pressure was 150/90 mm Hg, heart rate was 98 beats per min, and body-mass index was 31 ...kg/m2. Serum concentrations of D-dimer (>34 mg/dL; normal <0·5) and C-reactive protein were increased (42 mg/L; normal <0·5); prothrombin time, partial thromboplastin time, fibrinogen, creatinine, electrolytes, aspartate aminotransferase, alanine aminotransferase, and high-sensitivity troponin T were within normal range. Activation of the coagulation system producing thromboses in the context of thrombocytopenia and hypofibrinogenaemia—as occurred in our patient—is similar to heparin-induced thrombocytopenia and to that seen in critically ill COVID-19 patients (video).
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