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991.
Mikhail V. Ivanov Dmitri Babikov 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(44):17708-17713
Theoretical treatment of ozone forming reaction is developed within the framework of mixed quantum/classical dynamics. Formation and stabilization steps of the energy transfer mechanism are both studied, which allows simultaneous capture of the delta zero-point energy effect and η-effect and identification of the molecular level origin of mass-independent isotope fractionation. The central role belongs to scattering resonances; dependence of their lifetimes on rotational excitation, asymmetry; and connection of their vibrational wave functions to two different reaction channels. Calculations, performed within the dimensionally reduced model of ozone, are in semiquantitative agreement with experiment. 相似文献
992.
Twelve patients with cavitating lung lesions of uncertain aetiology, who had percutaneous aspiration combined with the instillation of radiographic contrast media, are presented. A diagnosis was made in 11 of the 12 patients (92%). A positive culture was obtained in all patients already receiving treatment for lung abscesses. Cultures of lavage fluid were positive in 89% of infected cavities. The instillation of radiographic contrast media into the lung cavity assists biopsy of the cavity wall, can be used to lavage the cavity, and may facilitate expectoration of sputum. 相似文献
993.
OBJECTIVES: 1) To describe the asthma morbidity, primary care practices, and asthma home management of inner-city children with asthma; 2) to determine the responses of parental caretakers to asthma exacerbations in their child; and 3) to compare these responses to the recommendations of the National Heart, Lung, and Blood Institute (NHLBI) asthma guidelines for home management of acute exacerbations of asthma. DESIGN AND METHODS: A 64-item telephone survey was administered between July 1996 and June 1997 to 220 parental caretakers of 2- to 12-year-old children who had been hospitalized with asthma at an inner-city medical center from January, 1995 to February, 1996. Sociodemographics, primary care practices, asthma morbidity, and asthma home management were assessed. Parents were asked what they would do if their child "began wheezing and breathing faster than usual." RESULTS: Morbidity measures indicated that there were an average of 2.5 +/- 4.5 emergency department visits for asthma in the last 6 months, 1.6 +/- 2.2 hospitalizations for asthma in the last 12 months, and 18.1 +/- 17.9 asthma-related school absences in the previous school year. Most, but not all, of the families had primary care providers and most had phone access to them. Half of the families (51%) reported having been given a written asthma action plan. Only 30% of families with children age 5 years and older had peak flow meters. In contrast, almost all families (97%) had equipment for inhalation of beta-agonists. Only 39% of the 181 children with persistent symptoms were receiving daily antiinflammatory agents as recommended in the guidelines of the NHLBI. In response to the scenario of an acute exacerbation of asthma, no one mentioned that they would refer to a written plan, only 1 caretaker would measure peak flow and 36% would give beta-agonists. Two percent would give oral steroids initially, and 1 additional person would do so if wheezing continued 40 minutes later. Only 4% responded that they would contact their clinician. Reports of actual practice differed from the scenario responses in that more people began beta-agonists and oral steroids in response to an exacerbation in the past 6 months than said they would in response to the scenario. CONCLUSION: In this population of previously hospitalized inner-city children with asthma, the NHLBI guidelines for the home management of asthma exacerbations are not being followed. Interventions are needed to affect both clinician and caretaker practices. 相似文献
994.
995.
This study aimed to examine the overnight temperature pattern of babies during the prodromal phase of minor illnesses. The overnight rectal temperature pattern of 123 babies was recorded weekly from about 6 to at least 16 weeks old, while parents maintained detailed records of signs of illness. By analysis of patterns of signs and visits to the general practitioner, 86 periods of minor illness were identified, mostly upper respiratory tract infections, though it was not usually possible to identify the infection by conventional virology. Data were analysed separately for babies who had developed an adult-like night time temperature pattern and those who had not. In both groups, obvious signs of illness were preceded by a disturbance of night time temperature pattern. Temperature was significantly raised over control weeks, though few babies were clinically febrile. The greatest temperature disturbances were seen in the three days before illness, though some disturbances were seen up to seven days before. A similar disturbance of temperature was seen the night after diphtheria, pertussis, and tetanus immunisation, and individual responses to natural infection and immunisation were well correlated, suggesting that the temperature change is more a function of the host response than the infecting agent. 相似文献
996.
Launey T Ivanov A Kapus G Ferrand N Tarnawa I Gueritaud JP 《The European journal of neuroscience》1999,11(4):1324-1334
We used brainstem motoneurons recorded in organotypic slice co-cultures maintained for more than 18 days in vitro, together with multibarrel ionophoretic applications of glutamate receptor agonists and bath applications of specific blocking agents, to study the responses of rat brainstem motoneurons to glutamate receptor activation, and the contribution of these receptors to synaptic transmission. Differentiated brainstem motoneurons in vitro are depolarized by glutamate, N-methyl-d-aspartate (NMDA) and dl-alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) iontophoresis, and express NMDA, AMPA and also specific kainate receptors, as evidenced by (+/-)2-amino-5-phosphonovaleric acid (APV)- and (-)1-(4-aminophenyl)-3-methyl-carbamoyl-4-methyl-7, 8-methylenedioxy-3,4-dihydro-5H-2,3-benzo-diazepine [GYKI 53784 (LY303070)]-resistant depolarizations. Electrical stimulations applied to the dorsal part of the explant trigger excitatory synaptic potentials with latencies distributed in three regularly spaced groups. Excitatory postsynaptic potentials (EPSPs) in the earliest group have a similar latency and time course and correspond to monosynaptic activation. EPSPs in later groups have more scattered latencies and time courses and correspond to polysynaptic activation. Monosynaptic EPSPs are insensitive to the specific NMDA blocker APV, and are completely and reversibly suppressed by the non-competitive AMPA receptor antagonist GYKI 53784 (LY303070). Detailed analysis of the spontaneous excitatory synaptic activity shows that APV decreases the frequency of spontaneous EPSPs without modifying their shape or amplitude. We conclude that excitatory synapses on brainstem motoneurons in vitro are mainly activated through AMPA receptors (AMPA-Rs). NMDA receptors (NMDA-Rs) are present in the membrane, but are located either at extrasynaptic sites or silent synapses, and are not directly involved in synaptic transmission on motoneurons. On the contrary, NMDA receptors contribute to synaptic transmission within the premotor interneuronal network. 相似文献
997.
A B Zemliano? A A Pal'tsyn A M Svetukhin R N Korotkina L V Elagina M V Pavlova R P Terekhova E G Kolokol'chikova E I Bozh'eva L S Makhmudova A N Lebedeva L O Ivanov 《Khirurgiia》1999,(10):44-48
For the period from 1996 to 1998 in the Division of wounds and wound infection of A.V. Vishnevsky Institute of Surgery 92 patients with pyonecrotic forms of "diabetic foot" underwent thorough examination and treatment. The patients were divided into groups by the form of "diabetic foot": with pyonecrotic forms of "diabetic foot" without critical ischemia (group 1) and with it (group 2). In 18 patients of both groups the data of electron autoradiography were used to reveal peculiarities of the wound process. Group 1 patients had at admittance a large number of neutrophiles in various stages of destruction in biopsies of the wound. In patients of group 2 a great majority of the vessels in biopsies of the wound were in different stages of destruction with lost connections between their separate cells or some of their part absent. Separate cells (endotheliocytes and pericytes) which make up the walls of destroying vessels, were synthesizing RNA and were functionally active. In both groups, the studied parts of the wound before plastic repair of its defect usually represented as well developed granulation tissues with a number of microvessels and cells. Intensive synthesis of PNA in the cells of microvascular wall evidenced of their high functional activity, and the synthesis of DNA in them showed their ability for proliferation, i.g.--for growth. Thus, microangiopathy was reversible, and the solution of the problem of critical ischemia should be considered in the light of macroangiopathy. Thus, in patients of group 1 the cause of pyonecrotic damage consists in infection process, while in patients of group 2--in combination of infection with ischemia of the extremity. In both groups pyonecrotic disease of the extremity ruses at the background of severe disturbances of cellular immunity. 相似文献
998.
Experiments on 55 outbred adult white rats narcotized with calipsol (50 mg/kg intraperitoneally) showed that separate infusions of a synthetic creatine phosphate analog neoton (100 mg/kg) and calcium antagonist finoptin (0.1 mg/kg) into the carotid artery directly after infliction of dosed craniocerebral injury improve energy metabolism and limit the intensity of lipid peroxidation in the brain during the first hour of the posttraumatic period. 相似文献
999.
1000.
We wanted to assess the effect of tamoxifen treated women with breast cancer, as well as to examine patients with diabetes blood hypertension, and obesity. The influence of Tamoxifen was searched over the endometrium in patients treated with it for 3 years. In this research work is assessed the effect of this medicament from this risk group. The second risk group were the women with high blood pressure, obesity and diabetes mellitus. We used transvaginal sonography and the progesterone test to find endometrial pathology and especially endometrial cancer in asymptomatic women-measuring the depth of the endometrium, and using abrasio probatoria separata in order to find endometrial cancer. With these tests we found polyps, hyperplasia, and early endometrial cancer. We wanted with progesteron test and vaginal sonography in these risk groups to find endometrial pathology and especially early endometrial cancer in asymptomatic women. 相似文献