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51.
A series of new isoniazid hydrazones was synthesized by two procedures. In the first isoniazid was activated with diethoxymethyl acetate and condensed with the appropriate anilines. Alternatively, substituted anilines were activated by diethoxymethyl acetate and subsequently condensed with isoniazid. NMR study confirmed that both synthetic approaches gave the same tautomer. All compounds were screened for in vitro antimycobacterial activity. Most of them exhibited the same activity against Mycobacterium tuberculosis (MIC 1 μmol L−1) as isoniazid (INH), better activity against Mycobacterium kansasii 325/80 (MIC 0.125–0.250 μmol L−1), high value of selectivity index (SI) and IC50 between 0.0218 and 0.326 mmol L−1. Compound 2o with the best SI was used as a model compound for the stability test and was found to be stable at neutral pH, but under acidic conditions it slowly hydrolysed.  相似文献   
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This article presents local protocols for antithrombotic therapy used in a tertiary care institution—the cardiocenter of a university hospital. The protocols were discussed in detail among the whole team of physicians of the cardiocenter. This article addresses cardiac conditions requiring hospitalization whenever antithrombotic therapy is indicated. These protocols do not include antithrombotic therapy in other medicinal disciplines (e.g., orthopedics, surgery). These protocols are mostly based on the current guidelines of the European Society of Cardiology (ESC). The partial differences between the ESC guidelines and this text are usually based on the results of the latest clinical trials, which have not yet been included in the ESC guidelines.  相似文献   
55.
The Czech Society of Cardiology is proposing here the new classification of acute coronary syndromes at the time of the first medical contact. The proposal suggests to remove the terms “ST elevation myocardial infarction” and “non-ST elevation acute coronary syndrome” and to replace these terms by “acute coronary syndrome with ongoing myocardial ischemia” and “acute coronary syndrome without ongoing myocardial ischemia”. The proposed new classification better reflects current treatment approaches and will facilitate the decision making at the first medical contact.  相似文献   
56.
In non-invasive diagnosis of renal osteodystrophy the levels of bone minerals and the extent of bone turnover are evaluated. The contents of bone minerals are assessed quantitatively by different modalities of bone densitometry, among which the most accurate one is double-energy bone densitometry. So far no standard examination method was defined nor the most suitable portion of the skeleton for densitometric examination. In order to find such an area and also to assess the prevalence of bone demineralization, its severity and regional differences the authors made a cross-sectional study of bone density in dialyzed patients. The group comprised 45 patients, 24 men and 21 women subjected to regular dialyzation treatment for 20-24 months. In a lambda whole body bone densitometry was performed with evaluation of regional densities of the trunk, upper and lower extremities. At the same time the state of bone turnover was assessed arbitrarily using values of serum concentrations of intact parathormone; parathormone concentrations below 50 pg/ml were considered low, above 200 pg/ml high and concentrations within the mentioned range as the normal bone turnover. In the group of patients 62% had a high, 22% a normal and 16% a low bone turnover. The study provided evidence of a significant reduction of bone density (Z score <-1) in 58% of patients. In 92% of patients demineralization affected most and first the extremities. In 69% it affected the lower extremities and in 23% the upper ones. 8% of the patients had the most severe affections in the area of the trunk. This order of affliction was not influenced by bone turnover, sex and in women by age. The diaphysis of long bones seems to be a representative examination area of the skeleton for densitometric measurements in patients with regular dialyzation treatment.  相似文献   
57.
The cytogenetic effects of in vitro exposure to benzene were investigated in cultured bovine peripheral lymphocytes. Stable and unstable chromosome aberrations (CA) and sister chromatid exchanges (SCE) were examined. Cultures of lymphocytes from two healthy donors were treated with benzene at concentrations of 5, 10, 50, 100, 500 and 1000 micromol.l-1 for the last 24 hours and for 2 hours of cultivation, both without and with metabolic activation (S9). In the CA assays with conventional Giemsa staining for 24 hours without metabolic activation, no dose-dependence in the induced chromosome aberration was achieved. A significant elevation in the induction of CA was found only after the application of benzene at a dose of 100 micromol.l-1 (p<0.01). Similar results were observed using fluorescence in situ hybridization (FISH) method for the detection both of non-stable and persistent chromatid-type aberrations and in the SCE assay for 24 hours without S9. All the lower and higher concentrations tested have no positive influence on CA and SCE induction. In experiments with S9 a significant increase in CAs, and a dose-dependence was achieved after exposure to benzene for 2 hours at concentrations ranging from 50 to 500 micromol.l-1 (p<0.05 and p<0.01, respectively).  相似文献   
58.
Blood platelet activation is a complex process involved in the physiological hemostasis and also in a number of disorders. Platelets change their morphology, modify their surfaces glycoprotein receptors with adhesive functions. Procoagulant microparticles are shedding and the aggregates of platelets with leucocytes are appearing. The activated platelet can be detected by flow cytometry after imunofluorescent staining.  相似文献   
59.
The authors submit the case of a patient with polycystic degeneration of the kidneys where after haemorrhage from the anterior cerebral artery hypernatraemia developed and concurrently significant acceleration in the progression of renal insufficiency to failure developed. Hypernatraemia was caused by non-natrium osmotic diuresis conditioned by increased urea excretion. In chronological association with increased dietary protein intake renal insufficiency was hastened.  相似文献   
60.

Background  

The objective of this study was to review the effects of adjunctive corticosteroids on overall mortality and the need for mechanical ventilation in HIV-infected patients with Pneumocystis jiroveci pneumonia (PCP) and substantial hypoxemia (arterial oxygen partial pressure <70 mmHg or alveolar-arterial gradient >35 mmHg on room air).  相似文献   
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