4,232 research outputs found
Isolated Lepton Production at Colliders
The production of isolated leptons with high transverse momentum in high
energy e-e, p-p or e-p collisions is reviewed. The leptons are produced either
through boson splitting or by boson-boson collision and yield experimentally
simple and spectacular topologies which can be exploited to validate the
Standard Model or to search for new phenomena.Comment: 50 page
Electroweak Measurements
The measurements of electroweak sector of the Standard Model are presented,
including most recent results from LEP, Tevatron and HERA colliders. The
robustness of the Standard Model is illustrated with the precision
measurements, the electroweak fits and the comparisons to the results obtained
from low energy experiments. The status of the measurements of the boson
properties and rare production processes involving weak bosons at colliders is
examined, together with the measurements of the electroweak parameters in
collisions.Comment: 12 pages, Proceedings of "Lepton-Photon 2005", Upsalla, Swede
Improved variables for measuring the polarization
We discuss a few possible strategies for measuring the polarization of the
baryons produced in -annihilation at the
resonance through their inclusive semileptonic decays. After
reviewing the existing methods, a new method is proposed, based on the ratio of
the averages of the squared electron and neutrino energy, including both
perturbative and nonperturbative corrections. This variable minimizes the
statistical error on the polarization, while keeping the
systematic theoretical errors at the level of 1-2%. A number of other
polarization-sensitive variables are also discussed, such as averages of ratios
of the electron and neutrino energy and the distribution in the difference of
the electron and neutrino rapidities.Comment: 23 pages, 4 uuencoded figures, REVTe
Pheochromocytoma – clinical manifestations, diagnosis and current perioperative management
Pheochromocytoma is a neuroendocrine tumor characterized by the excessive production of catecholamines (epinephrine, norepinephrine, and dopamine). The diagnosis is suspected due to hypertensive paroxysms, associated with vegetative phenomena, due to the catecholaminergic hypersecretion. Diagnosis involves biochemical tests that reveal elevated levels of catecholamine metabolites (metanephrine and normetanephrine). Functional imaging, such as 123I-metaiodobenzylguanidine scintigraphy (123I-MIBG), has increased specificity in identifying the catecholamine-producing tumor and its metastases. The gold-standard treatment for patients with pheochromocytoma is represented by the surgical removal of the tumor. Before surgical resection, it is important to optimize blood pressure and intravascular volume in order to avoid negative hemodynamic events
Pelvic floor disorders in gynecological malignancies. An overlooked problem?
Cervical, endometrial, ovarian, vulvar, and vaginal cancers affect women of a broad age spectrum. Many of these women are still sexually active when their cancer is diagnosed. Treatment options for gynecological malignancies, such as gynecological surgery, radiation, and chemotherapy, are proven risk factors for pelvic floor dysfunction. The prevalence of urinary incontinence, fecal incontinence, and sexual dysfunction before cancer treatment is still unclear. Hypotheses have been raised in the literature that these manifestations could represent early symptoms of pelvic cancers, but most remain overlooked even in cancer surviving patients.
The primary focus of therapy is always cancer eradication, but as oncological and surgical treatment options become more successful, the number of cancer survivors increases. The quality of life of patients with gynecological cancers often remains an underrated subject. Pelvic floor disorders are not consistently reported by patients and are frequently overlooked by many clinicians. In this brief review we discuss the importance of pelvic floor dysfunction in patients with gynecological malignant tumors
Determination of pyrrolizidine alkaloids in dietary sources using a spectrophotometric method
Pyrrolizidine alkaloids (PAs) are a class of toxic compounds found in the composition of more than 6000 plants. People can be exposed to PAs by consuming phytotherapeutic products, food from crops contaminated with seeds of some species with high content of PAs, and/ or contaminated animal products like bee products. For this reason we developed and validated a method for quantitative determination of PAs, from the most frequently contaminated food sources, honey and flour. Colorimetric Ehrlich reagent method was used with standard addition (1mg/kg senecionine). The extraction solvent was methanol 50% acidified with citric acid to pH 2-3, as this solvent can be used for alkaloids and N-oxides. We found that, in extracting the alkaloid only once from the dietary sources, the percent of recovery is low (52.5% for honey, and 45.75% for flour). Using successive extractions, three times with the same solvent, the senecionine retrieval percentage increased to 86.0% for honey and 76.0% for flour. The method was validated using the following parameters: selectivity, linearity (0,25- 20 mg/ mL senecionine), accuracy (average recovery 93.5 - 107.93%) and precision (RSD 3,26-4.55%.). The calculated limit of quantification (0.174 mg/ mL) makes this method applicable for determining Pas occurring at toxic levels for consumers
Pancreatogenic type 3C diabetes
Background. The relationship between chronic pancreatitis and diabetes is well established. This form of diabetes is secondary to exocrine pancreatic disorder and is known as diabetes mellitus type 3c (T3cDM).
Materials and Methods. In this retrospective study we included 261 patients, 59 patients being diagnosed with chronic pancreatitis and secondary diabetes mellitus, and admitted in the Fundeni Clinical Institute, 2nd Department of Gastroenterology or N.C. Paulescu Institute/ Carol Davila University of Medicine and Pharmacy.
Results and Discussions. Patients were 22.2% women and 77.8% men, with an average age of 56.8 years and 53.4 years respectively. 63% came from urban areas. The mean duration of chronic pancreatitis was six years. Non-diabetic patients were compared with patients who were previously diagnosed with T3cDM and who had been analyzed for body mass index (BMI). Imaging investigations were also performed to confirm pseudotumors or pancreatic tumours. Patients already considered non-diabetic had basal blood glucose values and were mostly overweight and obese. In this context, insulin resistance cannot be excluded for this group of patients.
Conclusions. T3cDM is a new pathological entity that needs to be explored more deeply, and that should benefit from both a diagnostic stratification and treatment
New oral anticoagulants and their reversal agents
Atrial fibrillation is a commonly encountered pathology in medical practice, and its prevalence has shown a continuous rise over the past years. Atrial fibrillation has a significant impact on patients\u27 quality of life, not only due to the standard anticoagulant treatment with vitamin K antagonists that require close monitoring and dose adjustment, but also due to the fragile equilibrium between hemorrhagic and thrombotic risks. The introduction of new oral anticoagulants (NOACs) in the treatment guidelines for atrial fibrillation has improved the quality of life, as NOACs do not require close monitoring or dose adjustments. However, even if the safety profile of the NOACs regarding the hemorrhagic risk is superior to vitamin K antagonists, the problem raised by an unexpected hemorrhage (e.g. severe hemorrhage after an accident) and the need for efficient hemostasis in a chronic anticoagulated patient has remained unsolved. To find a solution for this problem, reversal agents for NOACs have been developed and tested, and two of them, idarucizumab and andexanet-alpha, have already been approved by the FDA, thus making NOACs increasingly appealing as a choice of anticoagulation treatment
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