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C-F functionalizations that provide C-C bonds are challenging synthetic transformations, due in part to the large C-F bond strength, short bond length, nonpolarizable nature, the production of fluoride, and the regioselectivity-in the case of multifluorinated substrates. However, commercially available highly fluorinated arenes possess great synthetic potential because they already possess the C-F bonds in the desired locations that would be difficult to selectively fluorinate. In order to take advantage of this potential, selective C-F functionalizations must be developed. Herein, we disclose conditions for the photocatalytic reductive alkylation of highly fluorinated arenes with ubiquitous and unactivated alkenes. The mild reaction conditions provide for a broad functional group scope, and the reaction is remarkably efficient using just 0.25 mol% catalyst. Finally, we demonstrate the utility of the strategy by converting highly fluorinated arenes to elaborate (hetero)arenes that contain 2-5 Caryl-F bonds via synergistic use of photocatalysis and SNAr chemistry.

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We present a case of a 54 years old female patient after anterior wall left ventricular myocardial infarction in 2005 who underwent coronary artery bypass graft (CABG) surgery requiring cannulation of the right internal jugular vein (IJV). She was admitted to a Department of Pulmonary Diseases with left bronchopneumonia (BPN) following 7 day treatment, with hemoptysis, dyspnoea and fevers. Duplex ultrasound (DUS) was used to diagnose flapping thrombus in the right IJV, severe thrombocytopenia and, in addition, progressing multiple infiltrates on X-ray a few days later. We empirically adjusted the treatment initiated in primary care and observed deterioration of the severe thrombocytopenia during treatment with low molecular weight heparine. We diagnosed heparin-induced thrombocytopenia (HIT) and, even though this indication was not included in our drug formulary, we initiated treatment with Arixtra (fondaparinux) 2.5 mg s.c. daily. Intensive conservative treatment was associated with significant clinical and laboratory improvement of the condition, significant regression of the IJV thrombus as well as the finding on X-ray. The final effective antibiotic treatment lasted 20 (amoxicillin + clavulanate) and 10 (clindamycin) days, respectively. Treatment with Arixtra (fondaparinux) continued in primary care and lasted a total of 65 days until normal thrombocyte levels were achieved, with gradual transition to oral anticoagulation treatment. The patient was discharged to primary care on the 23rd day of hospitalization when she was stabilized, a febrile and her cardiopulmonary functions were compensated. We did not identify any case of treatment of jugular thrombosis and concurrent HIT with fondaparin anywhere in the international literature.

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A new cellular model of the propagation of short ultrasonic waves in cancellous bone is introduced. The theoretical results derived from the proposed model have been compared with the well known macrocontinual Biot's theory. Independently, the experimental results obtained by the pulse transmission method for cancellous bovine bone and a model material have been reported. The data from time and frequency domain are analyzed and discussed in light of the two-phase description developed under long and short wave assumption.

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The paper discusses the applicability of a two-phase model of saturated porous materials for a description of the results of broadband ultrasonic studies of wave parameters in bovine trabecular bone. The analysis is focused on the role of the internal structure of the materials in the propagation of dilatational waves within the frequency range with a significant attenuation of wave energy due to absorption and scattering. The applicability of ultrasonic studies for the determination of characteristic macro- and micro-structural parameters of biomaterials using a model-based approach is considered.

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The Nováky Power Station (NPS) has been using since 1953 as fuel coal with a high content of As and with a low content of other metals. This involves a constant risk for the workers as well as pollution of the surroundings. The authors described 16 cases of chronic As intoxication in NPS workers after 22.3 +/- 8.4 years of exposure (especially stokers, maintenance workers, boiler cleaners). Among clinical symptoms prevailed sensory and motor polyneuropathy (13 cases), pseudoneurasthenic syndrome (10 cases), toxic encephalopathy (6 cases) and nasal septum perforation (2 cases). After 1989 the intoxications with As did not occur any more due to technical measures and health protection of the workers. The authors present a review of actual results of clinical, haematological and biochemical investigations and tests for metals (AAS methods) in biological materials of workers at risk in NPS (n = 70), exposed on average for 11.9 +/- 0.5 years, of average age 35.91 +/- 1.7 years (mean +/- SE) and compared the results to a matched control group of blood donors not exposed to metals (n = 29). In NPS workers significantly lower Hb values, higher serum creatinine, higher serum beta 2-microglobulin, higher As content in hair as well as higher serum Mn and Pb concentrations compared with the C-group were found. The exposed group had significantly lower serum Se concentrations (0.64 +/- 0.025 mumol/l (mean +/- SE) compared to Se levels of persons from an adjacent district. The authors stress the necessity of individual evaluation of the metal concentrations in relation to clinical findings. With prolonged exposure the situation can become more urgent not only because of chronic poisoning but also because of the cancerogenic effects of these elements on the human organism.

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Plerocercoids of the tapeworm Spirometra mansonoides produce a substance that stimulates growth of experimental hosts. We report purification of plerocercoid growth factor (PGF) to homogeneity by a process involving isolation and solubilization of plerocercoid membranes, isoelectric point selection by chromatofocusing chromatography or preparative isoelectric focusing, and anion-exchange chromatography. A radioreceptor assay (RRA) for human growth hormone (hGH) was used to detect PGF and purity of the 27.5-kDa protein was judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Proteolytic activity was detected in the 27.5-kDa protein by gelatin substrate PAGE. Characterization of PGF as a neutral cysteine proteinase was based on substrate and inhibitor specificities and dependence on pH and thiol-containing reagents. The association of hGH agonist and proteinase activities was shown by comparing RRA and hydrolytic activities in the presence and absence of the cysteine proteinase inhibitor E-64.

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OBJECTIVE: To determine the reliability of seven different alternative glucose test strips manufactured for use with three different glucose meters. RESEARCH DESIGN AND METHODS: Venous blood samples were obtained from volunteers to test trade name glucose test strips on the manufacturers' glucose meters (One Touch II, Glucometer II, and Glucometer III), and the remainder of each sample was used for laboratory determination of blood glucose levels. In addition to the trade name test strips, Quick Check and First Choice test strips were tested on all meters, and Biotel test strips were also tested on the Glucometer III. RESULTS: In linear regression analysis, the R2 ranged from 0.84 to 0.97 for the test strips compared with plasma glucose values. The test strips with the highest accuracy and precision at all ranges of blood glucose levels were the One Touch II and Glucometer III trade name strips and the Quick Check and First Choice alternative strips for the One Touch II glucose meter and the First Choice alternative strip for the Glucometer II. Subgroup analysis based on ranges of blood glucose values, however, revealed that the alternative strips were not as accurate as the trade name test strips, with the exception of the First Choice alternative test strip for the Glucometer II. All of the trade name test strips were more precise than the alternative test strips designed for the individual meters. CONCLUSIONS: Alternative glucose test strips can be used to predict the actual laboratory blood glucose values but are generally not as accurate or precise as the trade name test strips.

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The authors submit case-histories of four patients with traumatic ruptures of the aorta where the patients survived for 1-10 days. All cases were fatal. The general condition of the patients did not permit surgical operation. The survival time of the patients provides evidence that in rupture of the aorta it is in some instances possible to make inevitable examinations and operations. If time permits, then transport to a specialized department is indicated. The operation requires satisfactory approach and availability of extracorporeal circulation.

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The leukotactic function of patients with sarcoidosis was studied. A defect was found in 19 of the 20 patients tested and was due to moderately elevated serum levels of the chemotactic factor inactivator. The chemotactic factor inactivator levels were not as high as those previously reported in patients with Hodgkin's disease or cirrhosis of the liver. The effect of the inactivator was irreversible and was directed toward all three of the chemotactic factors tested. The physicochemical characteristics of chemotactic factor inactivator in serum from sarcoid patients resembled in most respects the features of chemotactic factor inactivator in normal serum. As expected, the generation of chemotactic activity in some sarcoid serums by zymosan was impaired. The results of this study may relate to some of the reported defects in expression of immunity in sarcoid patients.

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Description of three pterygia in a patient, two of them on temporal side. In neighbourhood of the latters large prominent concrements were present in Meibaumian glands which were rubbing conjunctiva and cornea at each eye movement. They were thought to be the cause of these pterygia. On further examinations of pterygia and their surroundings it was found that besides hairs on caruncle and eyelashes in inner canthus also other pathological changes on eyelids may be the cause. Basing on findings in further 253 pterygia it may be accepted that pterygia occur after permanent microtrauma of conjunctiva and cornea. Those microtrauma may be due to pathological hairs on caruncle or in inner canthus and rarely due to concretion of Meibaumian glands, granulomas, Meibaumian cysts, lacrymal points, cysts and warts. In this way all the doubts about origin of pterygia may be explained. Knowledge of the causal factors may help prophylaxis and therapy of pterygium.

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