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151.
Uvarov VYu YD Ivanov AN Romanov MO Gallyamov OI Kiselyova IV Yaminsky 《Canadian Metallurgical Quarterly》1996,78(8-9):780-784
In the present paper, the application of scanning tunneling microscopy in cytochrome P450s membrane topology is discussed. The method enables visualization of heme location in the lipid-bilayer-incorporated protein. It is supposed that the membrane-bound cytochrome P450 on the tunneling microscope substrate should behave as 'molecular diode'. A model explaining the liposome and the proteoliposome images observed is proposed. 相似文献
152.
SKh al-Shukri NN Petrishchev AG Gorbachev IA Mikha?lova IuA Bobkov IV Kuz''min SIu Borovets IB Savel''eva MV Korokhodkina 《Canadian Metallurgical Quarterly》1997,42(3):38-41
Continuous monitoring of dynamic changes of transcranial regional cerebral oxygenation (rSO2) was performed in 7 healthy volunteers (mean age 40.9 +/- 12.6 years; range 25-62 years) during normo- and hyperbaric oxygenation (HBO at 2.5 and at 1.95 ATA) using an INVOS 3100 cerebral oximeter. A significant change between HBO and control phase could be found in rSO2, alterations (p < 0.05; ANOVA, Tukey test). The results suggest that the calculation of rSO2 may be a useful method to monitor changes of oxygen saturation under hyperbaric conditions. However, the absolute quantification of rSO2 is useless at the moment and needs further investigation. 相似文献
153.
The purpose of this study was to determine the pharmacokinetics and absolute bioavailability of cisapride after intravenous (i.v.) and intragastric (i.g.) administration in healthy, adult horses. Five animals received single doses of 0.1 mg/kg, 0.2 mg/kg and 0.4 mg/kg cisapride by the i.g. route in an open, randomized fashion on different occasions separated by a washout period of at least 48 h. Four of these horses were also given a single i.v. dose of 0.1 mg/kg cisapride. Jugular venous blood was collected periodically up to 24 h after dosing. Plasma cisapride concentrations were measured by high-performance liquid chromatography. There was considerable inter individual variability in pharmacokinetic parameters. The mean (SD) values for systemic clearance (CI) and steady-state volume of distribution (Vss) were 494 (43.6) mL/h/kg and 1471 (578) mL/kg, respectively. Although the rate of cisapride absorption was quite rapid, only about half the i.g. dose was absorbed systemically. The average terminal half-life (t1/2) calculated over three i.g. doses was 2.06 h and that for i.v. administration was 2.12 h. The pharmacokinetics of cisapride from 0.1 mg/kg to 0.4 mg/kg were independent of the i.g. dose. 相似文献
154.
VN Buneva OA Andrievskaia IV Romannikova GV Gololobov RP Iadav VI Iamkovo? GA Nevinski? 《Canadian Metallurgical Quarterly》1994,28(4):738-743
The interaction of antibodies from blood sera of patients with autoimmune pathology, systemic lupus erythematosus with oligoribonucleotides was studied. The RNA-hydrolyzing activity was shown to be an intrinsic property of autoantibodies. Enzymic activity of antibodies in hydrolysis of poly(U) was estimated at 20-40% of that of RNase A. In contrast to known eukaryotic RNases, the autoantibodies possess a specific RNA-hydrolyzing activity for oligo r(A). The RNA-nicking activity of antibodies in hydrolysis of oligoadenylates was more higher than with hydrolysis of oligo d(A). Optimal conditions of r(pA)13 hydrolysis were selected, including the optimal of pH = 8.7. 相似文献
155.
Hudnall Stamm B. Tuma F. Norris F.H. Piland N.F. Van Der Hart O. Fairbank J.A. Stamm H.E. IV Higson-Smith C. Barbanel L. Levant R.F. 《IEEE engineering in medicine and biology magazine》2004,23(1):149-161
As human beings, we share the trait of being able to experience extreme fear A variety of events can bring about this level of distress, some of which occur naturally and others that are caused by human action. One such event, terrorism, results from human action. In recent times, there has been a shift from conventional weapons for war and terrorism to a type of weapon of mass destruction (WMD) that includes chemical, biological, radiological, nuclear, and high yield explosives (CBRNE) weapons These types of weapons, in addition to their obvious effects, may be particularly capable of causing widespread fear, confusion, and stress that may alter the long-term health of affected communities and the larger community's sense of well-being. 相似文献
156.
MS Ivanova SD Lapshin VV Roginski? NA Rabukhina IV Gunenkova AA Kotesheva 《Canadian Metallurgical Quarterly》1995,74(3):56-59
The authors view results of conservative and surgical treatment of constant tooth chronic periodontitis in 90 children and adolescents aged 7-18 20 hemisections, 45 apicoectomies, 10 radix amputations were performed. The patients were followed up 6 months to 5 years. X-ray films show osseous restoration on the maxilla tooth to complete in 5-6 months, on the mandible tooth in over 8 months. The authors describe indications and contraindications to such kind. 相似文献
157.
Data are submitted on the condition of haemodynamics of greater and lesser circulation in patients with ischemic heart disease (IHD) presenting with the bundle-branch block. On the basis of the results from a combined clinical-instrumental investigation involving electro- and echocardiography the authors present the early objective quantitative criteria for the diagnosis of those haemodynamic shifts occurring in formation of the bundle-branch block. The blockade of the left bundle of His has a more pronounced effect on the greater circulation haemodynamics while that of the right one--on the lesser circulation. The authors give a comparative assessment of haemodynamic effects of a single dose of isosorbide dindtrate and nifedinin in the patients. Nitrosorbide and corinfar improve contractility of the left ventricle, decrease pulmonary hypertension and overloading of the right side of the heart. 相似文献
158.
159.
SC Grant SP Guy WR Lamb NH Brooks PE Brenchley IV Hutchinson 《Canadian Metallurgical Quarterly》1996,62(7):910-916
Different groups of cytokines may initiate or inhibit the rejection process. We used the polymerase chain reaction to study the expression of cytokine mRNA for interleukin (IL)-2, -4, -6 and -10, tumor necrosis factor-alpha, and interferon-gamma in 187 biopsy specimens from 24 human cardiac transplant recipients 5-555 days after transplantation. Cytokine levels in the serum were also measured. Cytokine mRNA was detected in 38.5% of biopsy specimens. IL-10 mRNA was detected more frequently with mild or absent rejection (11.6% in grades 0 and 1 - vs. 1.4% in grades 2 and 3, P=0.01). Up to 90 days after transplantation, IL-2 mRNA was detected more frequently with moderate rejection (13% in grades 2 and 3 vs. 0% in grades 0 and 1, P=0.076), and IL-4 mRNA was detected more frequently with mild or absent rejection (16% in grades 0 and 1 - vs. 0% in grades 2 and 3, P=0.061). More than 90 days after transplantation, IL-2 mRNA was detected more frequently with mild or absent rejection (10% in grades 0 and 1 vs. 0% in grades 2 and 3, P=0.078). Serum IL-4 levels corresponding to biopsy specimens positive for IL-4 mRNA were higher than those corresponding to specimens negative for IL-4 mRNA (59 pg/ml vs. 32 pg/ml medians, P=0.028). Our results suggest that IL-10 and possibly IL-4 (T helper 2 cytokines) may suppress graft rejection, whereas IL-2 (T helper 1 cytokine) may promote cellular rejection. In addition, cytokine profiles may change with length of time after transplantation. The association of elevated serum levels of IL-4 with increased expression of intragraft IL-4 mRNA may suggest release of this cytokine from the graft into the circulation. 相似文献
160.