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951.
A cost-effectiveness (CE) analysis was performed of Bassini versus laparoscopic repair for primary inguinal hernia. Incremental costs per 1-year recurrence-free patient were calculated for the societal and hospital perspective. From the hospital perspective, the incremental CE ratio of laparoscopic repair is 5.348 guilders. From the societal perspective, laparoscopic repair is both less costly and more effective than Bassini repair. Results were sensitive to assumptions about recurrence rates, laparoscopic operating time, and return to work. Laparoscopic repair should replace Bassini repair in order to benefit society. From the hospital perspective, the decision to accept laparoscopic repair depends on the willingness to pay.  相似文献   
952.
WC Jean  CD Keene  SJ Haines 《Canadian Metallurgical Quarterly》1998,43(4):941-4; discussion 944-5
OBJECTIVE AND IMPORTANCE: We describe three cases in which ventrally situated cervical arachnoid cysts led to spinal cord or cervicomedullary compression after repeat craniocervical decompression for Chiari II malformations. CLINICAL PRESENTATION: All three patients underwent craniocervical decompression when their Chiari malformations became symptomatic. The first patient developed chronic vertiginous spells and headache and was treated with repeated craniocervical decompression procedures during several years. Seven months after undergoing her third decompression procedure, she developed severe dizzy spells, which were determined to be of brain stem origin. The second patient had a small, asymptomatic arachnoid cyst anterior to the brain stem discovered at age 6 years. After undergoing repeat craniocervical decompression for headaches 8 years after undergoing his first procedure, the patient developed severe neck pain and acute quadraparesis. A third patient underwent repeat craniocervical decompression at age 14 years for cranial nerve dysfunction. Postoperatively, he acutely developed paresis of extraocular movements and incoordination of the upper extremities. All three patients were found to have anteriorly situated arachnoid cysts compressing the brain stem and/or cervical spinal cord. INTERVENTION AND TECHNIQUE: Fenestration of the arachnoid cyst or drainage with cystoperitoneal shunting adequately treated acute brain stem or cervical spinal cord compression. All three patients had achieved satisfactory relief from their acute symptoms of neural compression at their follow-up examinations. CONCLUSION: An association between spinal arachnoid cysts and neural tube defects has previously been reported. However, the development of previously undetected spinal arachnoid cysts after craniocervical decompression was unexpected. We hypothesize that extensive craniocervical decompression may alter the cerebrospinal fluid pressure dynamics in such a way that the anterior subarachnoid space, previously compressed, may dilate. Occasionally, because of perimedullary arachnoiditis, the cerebrospinal fluid may become loculated and act as a mass. Direct fenestration or shunting may successfully treat this problem, and less extensive craniocervical decompression may avoid it.  相似文献   
953.
954.
Glutathione S-transferases (GST) are a family of detoxification isoenzymes that catalyze the conjugation of xenobiotics and their metabolites with reduced glutathione. Lead exposure in rats is known to induce GST isoenzymes in the liver and kidney. These changes in expression have potential use as biomarkers of lead exposure. Because two-dimensional electrophoresis (2-DE) enables one to analyze both protein abundance changes and chemical changes in protein structure, 2-DE was used to determine the effect of in vivo lead exposure on GST isoform expression in rat kidney cytosols. Male Sprague-Dawley rats were exposed to inorganic lead, and proteins were separated by conventional ISO-DALT and NEPHGE-DALT techniques and blotted for immunological identification. Lead exposure caused detectable inductions in both GSTP1 and GSTM1 and quantifiable charge modification in GSTP1. These preliminary data confirm the utility of 2-D electrophoretic GST analysis as indicative of lead exposure and toxicity and support its use for further elaboration of lead's effects on renal protein expression.  相似文献   
955.
When atherosclerotic plaques develop, the cross-sectional area of the artery at that point often increases to accommodate the plaque without any reduction in lumen size. In consequence the angiogram does not detect a high proportion of atherosclerotic plaques. The increase in size of the artery (compensatory dilatation-arterial remodelling) varies widely in degree between different plaques even in the same artery. Dilatation of a degree to prevent any loss of lumen size is regarded as adequate compensatory dilatation. In contrast, other plaques are associated with no or minimal increase in the vessel cross-sectional area and a reduction in lumen size in present (inadequate compensation). High-grade stenosis is in particular associated with a total failure of remodelling. Such plaques may have had a rapid growth phase, out-pacing the ability of the medial smooth muscle cells to undergo a rearrangement. The phenomenon of remodelling has important consequences for pathologists who use the traditional method of comparing the lumen size relative to the cross-sectional area of the vessel at the site of a plaque to measure stenosis. The area of the vessel at this point may be anything up to 60% above its size before the plaque developed. An error is introduced which on average overestimates diameter stenosis by 30% when compared to an angiographic equivalent method in which the lumen size at the lesion is compared to the lumen size at an adjacent segment of artery without a plaque.  相似文献   
956.
In vivo chronoamperometry was used to monitor changes in dopamine oxidation currents corresponding to dopamine efflux in the nucleus accumbens of rats after presentation of a conditioned light stimulus repeatedly paired with either yoked- or self-administered intravenous injections of the psychostimulant d-amphetamine. Daily conditioning trials began with a non-contingent drug injection, paired with a conditioned stimulus consisting of a 5 s flashing light and 30 s lights out, after which a house light was illuminated during the 3 h session, signalling drug availability. Each subsequent injection of d-amphetamine was paired with the conditioned stimulus. Electrochemical measures were taken on conditioning trials 4-7, and on each trial, intravenous d-amphetamine (0.25 mg/kg per injection) self-administration produced a significant maximal increase in mean dopamine oxidation currents of approximately 8 nA above baseline. Dopamine oxidation currents in rats receiving yoked d-amphetamine were approximately 5 nA above baseline by the fourth day of drug administration and reached approximately 8 nA on the seventh and final day of drug administration. On day 9 the first presentation of the vehicle injection and conditioned stimulus, in combination with illumination of the house lights, induced an immediate increase in nucleus accumbens dopamine oxidation currents in all rats that had previously received d-amphetamine. Subsequent presentations of the conditioned stimulus at 30 min intervals induced further increases in extracellular dopamine oxidation currents in both drug-treated groups. By the end of the 3 h session, both groups had similar maximal conditioned increases in dopamine oxidation currents of approximately 6 nA. These data are discussed with relation to the neurochemistry of drug craving.  相似文献   
957.
BACKGROUND: Experimentally induced depressed mood is a suggested model for retarded depression. We describe the neural response associated with induced mood and the locus of the interaction between systems mediating mood and cognitive function. METHODS: Normal subjects performed a verbal fluency task during induced elated and depressed mood states. Regional cerebral blood flow (rCBF) was measured as an index of neural activity using Positron Emission Tomography (PET). RESULTS: In both elated and depressed mood state rCBF was increased in lateral orbitofrontal cortex, rCBF was also increased in the midbrain in elated mood. In the depressed condition rCBF was decreased in rostral medial prefrontal cortex. Verbal fluency produced an expected increase of rCBF in left dorsolateral prefrontal, inferior frontal and premotor cortex, anterior cingulate and insula cortex bilaterally, the left supramarginal gyrus posteriorly and the thalamus. Activation in the verbal fluency task was attenuated throughout the left prefrontal, premotor and cingulate cortex and thalamus in both elated and depressed mood conditions. An attenuation of anterior cingulate activation was specific to depressed mood. CONCLUSIONS: Alteration of mood is associated with activation of orbitofrontal cortex which may be critical to the experience of emotion. The mood induced modulation of verbal fluency induced activations is consistent with resting state findings of decreased function in these regions in depressed patients. The present data suggest that resting state rCBF profile may represent the modulation of spontaneous activity in this network by a core system that is dysfunctional in depression.  相似文献   
958.
We report a very rare case of systemic sclerosis in a 6-year-old girl. She presented with diffuse scleroderma, Raynaud's phenomenon, pulmonary interstitial fibrosis, pulmonary hypertension, and right ventricular failure. The diagnosis was confirmed by skin manifestations, high resolution computed tomography, cardiac catheterization, and anti-nuclear antibodies. Nifedipine, prednisolone, digoxin, and furosemide were given. There was remission of the right ventricular failure and dyspnea, and the skin showed partial improvement. The patient remained asymptomatic for a year. The symptoms of respiratory and right heart failure developed again after an episode of lower respiratory tract infection and she eventually died. We discuss the clinical manifestations, treatment, and outcome.  相似文献   
959.
It was reported previously that IgD-receptors (IgD-R) are expressed on both CD4+ and CD8+ human T cells and CD4+ murine T cells after exposure to oligomeric IgD, certain cytokines, or various pharmacological agents, as shown by rosetting with IgD-coated erythrocytes. Enhancement of antibody production is observed in mice after injection of oligomeric IgD and is mediated by these IgD-R+ T cells, while injection of monomeric IgD inhibits both IgD-R upregulation and augmentation of antibody responses induced by simultaneously injected oligomeric IgD. The effects of oligomeric IgD on IgD-R upregulation are lacking in aged mice. However, the oligomeric IgD induced enhanced antibody production can be transferred to aged mice with IgD-R+ T cells from young donors suggesting that the environment of the aged mouse supports the effector function of IgD-R+ T cells. We now report, in addition, that exposure to phosphatidylcholine (PC) and a PC-containing lipid mixture, AL721, is effective in causing IgD-R upregulation on T cells from both young and aged mice, and young humans. This effect can also be demonstrated in mice in vivo after administration of AL721. Moreover, this agent causes a two-fold enhancement of antibody production, as measured by PFC/spleen, to 4-hydroxy-5-iodo-3-nitrophenyl(acetyl)-Brucella abortus (NIP-BA) and NIP-horse red blood cells (RBC) in young and aged mice. There is no difference in the baseline membrane fluidity of lymphocytes from aged and young mice. Although PC causes an increase in membrane fluidity of lymphocytes from both young and old mice, and from humans, this effect on fluidity is not prevented by a protein kinase inhibitor, while PC's effect on IgD-R upregulation is prevented by the inhibitor. Moreover, no correlation was observed between IgD-R upregulation and membrane fluidity changes induced by AL721 administered in vivo. To evaluate the role of IgD-R induction in the augmentation of antibody production by phospholipids, the effect of monomeric IgD was investigated. The augmenting effect of AL721 on antibody production was prevented by a single injection of monomeric IgD at the time of antigen administration. We conclude that (1) PC-containing lipid mixtures are effective in enhancing antibody production in aged mice, (2) induction of IgD-R is responsible for the augmenting effects of AL721 on antibody production, and (3) monomeric IgD not only blocks the upregulation of IgD-R, as shown previously, but also the augmenting effect of previously upregulated IgD-R on T cells by preventing their interaction with surface IgD+ B cells.  相似文献   
960.
The key signal transduction enzyme protein kinase C (PKC) contains a hydrophobic binding site for alcohols and anesthetics (Slater, S. J., Cox, K. J. A., Lombardi, J. V., Ho, C., Kelly, M. B., Rubin, E., and Stubbs, C. D. (1993) Nature 364, 82-84). In this study, we show that interaction of n-alkanols and general anesthetics with PKCalpha results in dramatically different effects on membrane-associated compared with lipid-independent enzyme activity. Furthermore, the effects on membrane-associated PKCalpha differ markedly depending on whether activity is induced by diacylglycerol or phorbol ester and also on n-alkanol chain length. PKCalpha contains two distinct phorbol ester binding regions of low and high affinity for the activator, respectively (Slater, S. J., Ho, C., Kelly, M. B., Larkin, J. D., Taddeo, F. J., Yeager, M. D., and Stubbs, C. D. (1996) J. Biol. Chem. 271, 4627-4631). Short chain n-alkanols competed for low affinity phorbol ester binding to the enzyme, resulting in reduced enzyme activity, whereas high affinity phorbol ester binding was unaffected. Long chain n-alkanols not only competed for low affinity phorbol ester binding but also enhanced high affinity phorbol ester binding. Furthermore, long chain n-alkanols enhanced phorbol ester induced PKCalpha activity. This effect of long chain n-alkanols was similar to that of diacylglycerol, although the n-alkanols alone were weak activators of the enzyme. The cellular effects of n-alkanols and general anesthetics on PKC-mediated processes will therefore depend in a complex manner on the locality of the enzyme (e.g. cytoskeletal or membrane-associated) and activator type, apart from any isoform-specific differences. Furthermore, effects mediated by interaction with the region on the enzyme possessing low affinity for phorbol esters represent a novel mechanism for the regulation of PKC activity.  相似文献   
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