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71.
SV Varha OH Reznikov IS Turchyn VM Demchenko OP Potikha PV Sinitsyn LV Tarasenko LV Cha?kovs'ka 《Canadian Metallurgical Quarterly》1994,40(5-6):105-109
The effect exerted by transplantation of the 5 day culture of testicles from newly born piglets on the hypogonadal state of mature X-ray irradiated (3 Gy) rats was studied. It has been found that a month after transplantation (two months after irradiation) the hypogonadal state disappeared for a while, which is confirmed by normalization of the weight of seminal vesicles, content of testosterone and biologically active lutropine, restoration of the reproductive function of rats. No significant changes in steroidogenesis activity have been found, which proves a substituent character of transplantation. The effect disappears three months later but certain restoration of the content of nucleic acids in the testicles is observed. 相似文献
72.
The role of intramuscular botulinum toxin A in the treatment of 26 children with cerebral palsy was evaluated. The indication for injection was the presence of a dynamic contracture of lower-limb muscles interfering with positioning or walking. Spastic target muscles were identified by clinical examination and, in ambulant children, by gait analysis. Between 50 and 320 units of botulinum toxin were injected into each muscle group to a total dose of 100 to 400 units per child. The effects of injection were monitored by repeated clinical examination and gait analysis. There were no clinically detectable systemic side-effects, and all but one patient had a reduction in tone, which occurred within three days and persisted for two to four months. There were significant improvements in ambulatory status and in sagittal-plane kinematics. In some cases these gains persisted after the tone-reducing effects of the toxin had worn off. 相似文献
73.
74.
IS Grewal P Borrow EG Pamer MB Oldstone RA Flavell 《Canadian Metallurgical Quarterly》1997,9(4):491-497
Research in the past few years has documented significant advances in our understanding of the CD40-CD40 ligand (CD154) system in diverse immune functions. This system influences many T cell mediated inflammatory immune responses and effector functions, unmasking a previously unexpected role for CD40-CD154 in cell mediated immunity. Manipulation of CD154 in animal models of infection by the use of CD154-deficient mice or anti-CD154 antibodies has shown the importance of this system in the initiation of the inflammatory response, in the activation of antigen-presenting cells and in resistance to infections. 相似文献
75.
JE Biaglow CJ Koch SW Tuttle Y Manevich IS Ayene EJ Bernhard WG McKenna AV Kachur 《Canadian Metallurgical Quarterly》1998,42(4):769-773
PURPOSE: Methylene blue (MB) can be used as an intracellular electron acceptor. The purpose of this study was to demonstrate the usefulness of MB for the determination of total bioreductive capacity of cell suspensions. METHODS AND MATERIALS: We measured oxygen consumption by Clark electrode and pentose cycle activity by release of 14CO2 from 1-14C-glucose. RESULTS: Methylene blue catalyzes the reaction of intracellular reductants NADPH, NADH, and reduced glutathione (GSH) with oxygen, causing the production of hydrogen peroxide. The reaction rate correlates with the negative charge of molecule (NADPH(-4) > NADH(-2) > GSH(-1)), suggesting that reaction with positively charged oxidized MB is the limiting step of the reaction. In a cellular system MB causes the electron flow from cellular endogenous substrates to oxygen. It is activated by the disruption of the NADP+/NADPH ratio due to several processes. These are direct oxidation of NADPH and GSH, the GSH peroxidase catalyzed reaction of GSH with H2O2, followed by NADPH oxidation by oxidized glutathione (GSSG). This results in increased cellular oxygen consumption and stimulation of the oxidative limb of pentose cycle (PC) in the presence of MB. The cellular effect of MB differs from other electron accepting drugs. Diamide and tert-butylhydroperoxide act as direct oxidants, while MB is an electron carrier to oxygen. Accordingly, MB shows the highest effect on PC activation and oxygen consumption. CONCLUSIONS: Our results indicate that MB may be used for the determination of the total bioreductive capacity of the cells, measured by oxygen consumption and PC activation. 相似文献
76.
To gain more insight into decision making around the termination of resuscitation (CPR), we studied factors which influenced the time before discontinuing resuscitation, and the criteria on which those decisions were based. These criteria were compared with those of the European Resuscitation Council (ERC) and the American Heart Association (AHA). For this study, we reviewed the audiotapes of resuscitation attempts in a hospital. A total of 36 attempts were studied, involving 27 men and nine women, mean (S.D.) age 64 (18) years. A total of 19 patients received resuscitation on general wards, and 17 in the emergency room after an out-of-hospital circulatory arrest. The median interval time (range) from start to termination was 33 min (8-81 min). Results from multiple linear regression showed that a delay greater than 5 min in first advanced life support measures, drawing a sample for biochemical analysis, and the patient's response shown by return of spontaneous circulation were independently associated with the time of terminating resuscitation. The team used a number of criteria which can be found in the guidelines of the ERC and the AHA, but also used additional criteria. The ERC and the AHA criteria were not sufficient to cover all termination decisions. We conclude that the point in time to terminate resuscitation is not always rationally chosen. Updating of the current guidelines for terminating resuscitation and training resuscitation teams to use these guidelines is recommended. 相似文献
77.
GI Cubero JJ Reguero A Batalla E Simarro IS Posada S Braga JL Negrete 《Canadian Metallurgical Quarterly》1998,53(5):269-273
Therapeutic interventions in the skeletal system are an essential part of interventional radiology. Although in terms of figures these procedures are applied less frequently, they are very effective. Percutaneous transarterial embolization of a spinal tumor is well-established interventional treatment. It is primary treatment for preoperative devascularization, but also for palliation of pain and for reduction of tumor volume. As an alternative access for embolization, direct percutaneous puncture of a vertebra is used. A new and promising technique is vertebroplasty, the percutaneous injection of acrylic surgical cement in destroyed vertebrae. The present paper discusses indications, technique, results and complications of these interventional therapeutic modalities in the treatment of primary and secondary spinal tumors. 相似文献
78.
This review evaluates the various lines of evidence supporting the hypothesis that cholecystokinin (CCK) released from the small intestine during feeding plays a physiological satiety. Issues considered include, the effects of systemic injection of CCK on consummatory and operant feeding, the role of the vagus nerve, the effects of CCKB receptor antagonists, and the neuroendocrine responses to exogenous CCK. A critical appraisal of this research indicates that while it is clearly demonstratable that exogenous peripheral CCK can alter food intake by acting on CCKA receptors, the mechanism involved may be more closely related to the induction if aversion and nausea, rather than satiety. With regard to peripheral endogenous CCK, the available evidence also does not seem to support a role for the hormone in satiety. In particular, it is doubtful whether plasma concentrations of CCK following a meal are sufficiently high to inhibit feeding. Moreover, CCKA receptor antagonist which do not cross the blood brain barrier fail to increase meal size, as would be expected if peripheral CCK was an effective satiety factor. In addition, the recent literature concerned with the possibility that CCK may have a direct action within the brain in the control of food intake has been reviewed. These studies show that CCK administered intracerebroventicularly, or by micoinjection into discrete brain regions, also inhibits feeding via a CCKA receptor mechanism. However, the physiological relevance of these findings have yet to be determined. 相似文献
79.
High-sensitivity titration calorimetry is used to measure changes in enthalpy, heat capacity and protonation for the binding of captopril to the angiotensin I-converting enzyme (ACE; EC 3.4.15.1). The affinity of ACE to captopril is high and changes slightly with the pH, because the number of protons linked to binding is low. The determination of the enthalpy change at different pH values suggests that the protonated group in the captopril-ACE complex exhibits a heat protonation of approximately -30 kJ/mol. This value agrees with the protonation of an imidazole group. The residues which may become protonated in the complex could be two histidines existing in two active sites, which are joined to the amino acids coordinated to Zn2+. Calorimetric measurements indicate that captopril binds to two sites in the monomer of ACE, this binding being enthalpically unfavorable and being dominated by a large positive entropy change. Thus, binding is favored by both electrostatic and hydrophobic interactions. The temperature dependence of the free energy of binding deltaG degrees is weak because of the enthalpy-entropy compensation caused by a large heat capacity change, deltaCp =-4.3+/-0.1 kJ/K/mol of monomeric ACE. The strong favorable binding entropy and the negative deltaCp indicate both a large contribution to binding due to hydrophobic effects, which seem to originate from dehydration of the ligand-protein interface, and slight conformational changes in the vicinity of the active sites. 相似文献
80.