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1.
Lidocaine with epinephrine is currently the most common local anesthetic agent used for impacted third molar surgery. The purpose of the present study was to define the adverse hemodynamic effects and plasma concentrations of lidocaine and epinephrine on 17 healthy patients during the impacted teeth operations. Arterial blood pressure (systolic blood pressure, diastolic blood pressure), heart rate, peripheral oxygen saturation range, and electrocardiography were measured by an automatic noninvasive pressure device and monitor. High-performance liquid chromatography was used to measure the changes of plasma concentrations of epinephrine and lidocaine from blood samples taken 5 different times during the operation. We concluded that lidocaine-epinephrine is effective local anesthetic and had no important adverse events in healthy patients during the third molar surgery.  相似文献   
2.
In 24 patients with diagnostically not clear, short, recurrent episodes of consciousness disturbances and heart diseases and/or a history of arrhythmia simultaneous 24-hour recording was done of eeg and ecg. In the differential diagnosis epilepsy was considered, especially since in most cases routine eeg records demonstrated slight episodic changes. During 24-hour recording in 8 cases typical episodes of consciousness disturbances developed but in none of them these episodes were associated with arrhythmia which ruled out their cardiogenic origin. In 2 cases EEG recording served for establishing the diagnosis of partial complex seizures, 2 patients had hyperventilation syncope, one had TIA, in the remaining 3 cases absence of eeg and ecg changes during these episodes and coexistence of anxiety neurosis suggested functional origin. So the combined 24-hour eeg+ecg recording made possible establishing of diagnosis in 1/3 of these patients, enabling adequate treatment to be instituted.  相似文献   
3.
Carbon dioxide and propylene oxide (PO) were copolymerized using diethylzinc in addition with benzenedi- and triols, aliphatic diols and triols, and aminophenols as catalyst systems. A large amount of CO2/PO alternating copolymer, {poly(propylene carbonate), poly(oxycarbonyloxypropylene), of high molecular weight was obtained using the homogeneous (C2H5)2Zn/pyrogallol (2:1 by mole) system ( 1 ). The (C2H5)2Zn/o-aminophenol system ( 2 ) (also homogeneous) appeared to be much less active in the copolymerization of CO2 with PO than the former one. From the other studied systems, that appeared to be heterogeneous, (C2H5)2Zn/resorcinol (1:1 by mole) was the most active one, but less active than the system 1 . Further, the copolymerization of CO2 and PO was studied in the presence of the (C2H5)2Zn/resorcinol (1:1 by mole) system at various temperatures and in reaction media of different basicity. On the basis of the obtained results of the copolymerization of CO2 with PO and of measurements of the quantity of ethane evolved in the reactions between the catalytic systems' components, structures of several catalysts, particularly homogeneous ones, are suggested and some aspects of the copolymerization mechanism are discussed.  相似文献   
4.
Investigations on the reactions of diethylzinc ( 1 ) with resorcinol ( 2 ) and phloroglucinol ( 8 ) were carried out for different mole ratios of the reactants. It was found that the reaction of 1 with 2 at a mole ratio of 1:1 is a two step process. In the first step 1 reacts very rapidly with half of applied 2 yielding di(ethylzinc) resorcinolate ( 6 ), which then reacts slowly with the remaining amount of 2 . It was found that zinc 3-ethylzincoxyphenolate resorcinolate ( 5 ) formed in the second step is an active catalyst of the copolymerization reaction of carbon dioxide with propylene oxide. The reaction of 1 with 8 shows a similar course.  相似文献   
5.
Complexes of acrylonitrile and of methyl methacrylate with various Lewis acids, 1 and 2 , were studied by means of IR, NMR, and UV spectroscopy. The influence of the Lewis acid strength on the induction effect and on the delocalization of π-electrons in the complexed monomer molecule was established. As the relative acidity of the complexing agent is increased, the inductive effect of the nitrile or of the carbonyl group in the complex molecule rises, whereby the electron density on the carbon atom in β-position in the vinyl group diminishes. Complexation of the monomer also results in increased delocalization of π-electrons in the molecule. In the complexes with moderately strong Lewis acids like CH3AlCl2 and C2H5AlCl2, delocalization of π-electrons seems to reach its maximum. The methyl methacrylate-C2H5AlCl2 complex was found to give a charge-transfer complex with 1,5-cyclooctadiene. On the basis of the present spectroscopic studies and of earlier studies on copolymerization of acryl monomers with butadiene, the delocalization of π-electrons in the complexed monomer molecule is believed to be one of the major factors controlling the rate of copolymerization.  相似文献   
6.
The copolymerizations of acrylonitrile, methacrylonitrile, methyl acrylate, methyl methacrylate, methyl vinyl ketone, acroleine, and acrylic acid with butadiene were carried out in the presence of the Lewis acids ZnCl2, BF3, CH3AlCl2, C2H5AlCl2, AlCl3, SnCl4, and TiCl4 and also in the absence of catalyst. Relative reactivity orders of the above polar vinyl monomers in the copolymerization and 1,4-cycloaddition reactions with butadiene and also the catalytic activity orders of Lewis acids in these reactions were determined. The composition of the polymers formed and the structure of their butadiene units were also determined. The mechanism of the copolymerization and 1,4-cycloaddition of the polar vinyl monomers with butadiene in the presence of Lewis acids is discussed.  相似文献   
7.
Investigations of calcium-phosphate metabolism were carried out in a group of 11 children and adults with intracerebral calcifications. It was possible to isolate three different pathogenetic types of calcifications in the striatum and dentate nuclei in the cerebellum. The authors suggest restriction of the term "Fahr's syndrome" to cases without true of false hypoparathyroidism. The assessment of the calcium-phosphate metabolism, and particularly, the test with parathyroid hormone, seem to be an indispensable element in the differential diagnosis of this type of intracerebral calcifications.  相似文献   
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Abstract:  One of the targets of modern plant physiology is to identify tools for improving seed germination and plant growth under unfavorable environmental conditions. Seeds of Brassica oleracea rubrum were pretreated with melatonin at concentrations: 1, 10, and 100 μ m using a hydropriming method. Air-dried seeds of each experimental variants that were nonpretreated (control), hydroprimed (H) or hydroprimed with melatonin (HM1, HM10, and HM100) were germinated in darkness for 3 days at 25°C. Young seedlings were then transferred to the light and grown for an additional 5 days. Both germination and growth tests were performed in water and in CuSO4 water solutions in concentrations of 0.5 and 1 m m . H, HM1 and HM10 improved seed germination both in water and in the presence of Cu2+. One or 10 μ m melatonin eliminated the inhibitory effect of the 0.5 m m metal concentration on the fresh weight of seedlings. HM100 had a negative effect; thus seed germination was lower and seedlings had poor establishment. The toxic effect of Cu2+ manifested by membrane peroxidation and DNA endoreplication blocking in the seedlings grown from nontreated (control) and H seeds was not observed in the seedlings grown from HM1 and HM10 seeds; in contrast, HM100 enhanced the toxic effect of Cu2+.  相似文献   
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