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941.
942.
943.
Background: Bupivacaine retards myocardial acidosis during ischemia. The authors measured function of rat isolated hearts after prolonged storage to determine whether bupivacaine improves cardiac protection compared with standard cardioplegia alone.

Methods: After measuring cardiac function on a Langendorff apparatus, hearts were perfused with cardioplegia alone (controls), cardioplegia containing 500 [mu]m bupivacaine, or cardioplegia containing 2 mm lidocaine; were stored at 4[degrees]C for 12 h; and were then reperfused. Heart rate and left ventricular developed pressures were measured for 60 min. Maximum positive rate of change in ventricular pressure, oxygen consumption, and lactate dehydrogenase release were also measured.

Results: All bupivacaine-treated, four of five lidocaine-treated, and no control hearts beat throughout the 60-min recovery period. Mean values of heart rate, left ventricular developed pressure, maximum positive rate of change in ventricular pressure, rate-pressure product, and efficiency in bupivacaine-treated hearts exceeded those of the control group (P < 0.001 at 60 min for all). Mean values of the lidocaine group were intermediate. Oxygen consumption of the control group exceeded the other groups early in recovery, but not at later times. Lactate dehydrogenase release from the bupivacaine group was less than that from the control group (P < 0.001) but did not differ from baseline.  相似文献   

944.

Background  

The justification for Nazi programs involving involuntary euthanasia, forced sterilisation, eugenics and human experimentation were strongly influenced by views about human dignity. The historical development of these views should be examined today because discussions of human worth and value are integral to medical ethics and bioethics. We should learn lessons from how human dignity came to be so distorted to avoid repetition of similar distortions.  相似文献   
945.
In their recent review article, Tanvetyanon and Stiff [1] pointedout that hypocalcemia is a frequent side-effect of intravenousbisphosphonates. This adverse event is usually mild and exceptionallysymptomatic, with the principle risk factors being pre-existinghypovitaminosis D, previous parathyroid surgery and intestinalresections. A direct consequence of hypocalcemia  相似文献   
946.
947.
Auditory P300 and eye tracking dysfunction in schizophrenic pedigrees   总被引:4,自引:0,他引:4  
Several psychophysiological abnormalities associated with schizophrenia have been proposed as genetic trait markers of vulnerability to the disorder. Smooth pursuit eye tracking dysfunction and abnormal long latency event-related potentials are the most promising candidates. Both are independent of the effects of psychotropic medication or mental state at the time of testing, and twin studies demonstrate that each has a high level of heritability. Having recorded smooth pursuit eye tracking and event-related potentials in 20 high-density schizophrenic families, we find abnormalities in one or both measures in most of the families studied. The abnormalities, when present, occur in the family members with schizophrenia and other forms of functional psychosis, and they have a bimodal distribution with approximately half the nonschizophrenic relatives also showing eye tracking dysfunction and/or abnormal event-related potentials. Some of these relatives had psychiatric symptoms; others were normal. Our results suggest that psychophysiological examination can help to clarify the boundaries of schizophrenia spectrum disorder. By helping to decide the phenotypic status of nonschizophrenic family members, this should increase the power of DNA linkage studies.  相似文献   
948.
We previously showed that a low frequency (1 Hz) train of perforant path stimulation evokes burst discharges in the dentate gyrus of hippocampal slices obtained from patients surgically treated for intractable temporal lobe epilepsy. We report here that multiple population spikes that characterize the burst discharge are blocked reversibly by the specific NMDA receptor antagonist, D-(-)-2-amino-5-phosphonovaleric acid (D-APV). The epileptiform discharge evoked in human dentate gyrus by stimulation trains of 1 Hz could be reproduced in the rat dentate gyrus in vitro by the same stimulation protocol but required the presence of low concentrations (0.2-0.6 mM) of extracellular magnesium. We suggest that low frequency orthodromic stimulation of dentate granule cells through the perforant path progressively evokes an increase in the activation of NMDA receptors resulting in burst discharges in tissue from epileptic patients.  相似文献   
949.
Infantile myofibromatosis is an uncommon, benign, probably hamartomatous proliferation of myofibroblasts. Its growth is typically self-limiting but histologically it can simulate a sarcoma. A rare case of solitary infantile myofibromatosis presenting as an intraoral mass in a 10-year-old girl is reported.  相似文献   
950.
Deep venous thrombosis in the surgical intensive care unit   总被引:4,自引:0,他引:4  
The ICU patient population is at a high risk for the development of deep venous thrombosis leading to a potentially fatal pulmonary embolism. It is vital to appreciate this risk and apply appropriate prophylaxis. Constant vigilance is required, as deep venous thrombosis and pulmonary emboli can develop and progress despite standard prophylactic measures. In unstable patients, more aggressive prophylaxis may be warranted, including the use of inferior vena cava filters. A high index of suspicion and a low threshold for screening and diagnostic testing will allow earlier recognition and treatment of this lifethreatening condition. Treatment decisions are based on clinical suspicion, diagnostic examination results, and the potential complications of difficult treatment modalities.  相似文献   
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