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The effect of heparin on plasma ionised calcium was studied by adding it in increasing amounts to whole blood from 10 normal subjects. There was no significant change in ionised calcium from the addition of 1 U/ml but a significant fall of 0.02 mmol/1 when 2 U/ml were added and a progressive further fall with increasing concentrations. Heparin from three different manufacturers produced similar results. The effect of heparinisation in vivo was studied during regular haemodialysis on 10 patients with chronic renal failure. Following intravenous injection of 10000 U of heparin there was a consistent and significant fall averaging 0.03 mmol/l.  相似文献   
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On the basis of previous empirical research it was hypothesised that (a) antisocial behaviour in adolescence would be characterised by lower tonic heart rate levels and (b) any such relationship would be particularly borne out in the higher social classes where the 'social push' towards antisociality may be relatively weaker. These predictions were tested by relating tonic heart rate levels in a sample of 15 year old male schoolchildren to self-report and teacher ratings of antisocial behaviour/undersocialization. An 'antisocial' group was found to have significantly lower heart rate levels than a 'prosocial' group. Several analyses on high and low class groups resulted in a significant low heart rate/antisociality relationship in the high classes only. It was speculated that the heart rate/antisociality relationship may be mediated by somatotype, or alternatively that low levels in high class antisocials may reflect a vagal passive adaptation to mildly aversive events.  相似文献   
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The distribution of HLA antigen frequencies has been studied in patients with affective disorders. There were no significant differences between bipolar patients, unipolar patients, or controls. Preliminary data on HLA antigen distribution in schizophrenic patients are reported. Our negative results in affective disorders are discussed in relation to HLA studies reported from other laboratories, with special reference to some potential methodological problems.  相似文献   
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Features of paw edema induced by subplantar injection of actinomycin D (act D) were investigated in rats. The paw edema was produced as early as the 1st day and reached a maximal level on the 3rd or the 4th day. Thereafter, it began to subside progressively and was considerably reduced by the 16th day following act D (20 μgm) injection. A direct dose response relationship between the amount of act D injected and the intensity of the paw edema was obtained. No difference in β-glucuronidase and acid phosphatase activity was found between saline and act D-injected paws on the 2nd day. This was followed by an increase in the activity of both enzymes on the 4th, 8th, and 16th days after injection. The histamine content of the saline and act D-injected paws remained unchanged during the early phase of inflammation. A marked increase in the histamine content was noted during the late phase in the drug-injected paw. The effects of act D treatment on capillary permeability to Evans blue dye (EBD) and the edema formation of the paw revealed that a maximal increase in vascular permeability to EBD occurred on the 1st day and was maintained until the 8th day. In contrast to permeability, the paw edema on the 1st day was minimal and increased progressively until the 3rd or 4th day. Thereafter, both the permeability and the paw edema began to diminish and were considerably reduced on the 16th day. Aspirin and hydrocortisone treatment were ineffective in suppressing the act D-induced paw inflammation. Indomethacin produced a somewhat dose-related anti-inflammatory effect against the inflammation caused by this drug.  相似文献   
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The effect of cost containment on the practice of cardiology: predictions   总被引:1,自引:0,他引:1  
When health care cost containment is tied to unit pricing, the system may become price-driven rather than care-driven. Although the incentives engendered by unit pricing may not necessarily result in practices detrimental to the young or the patient with relatively pure disease, the potential for adverse effects on the elderly, the poor and the chronically ill is real. Hospitals will soon emphasize quick turnover, efficiency and intensive care. Diagnostic evaluations and chronic disease care will be moved out of hospitals into physician owned-and-operated facilities and out-of-hospital settings, respectively. The health care system will fractionate, and quality control will require restructuring to achieve the present level of quality assurance. Cardiologists, as well as other physicians, will need to alter their teaching style and teaching locations. Better methods for predicting outcomes will need to be developed; we will no longer have the safety net of following a patient closely and altering management plans according to the patient's response. Cost containment may occur under diagnosis related groups, preferred provider organizations, health maintenance organizations and other prepaid or "capped" systems. There are, however, many issues relative to cost versus quality that need to be resolved if severe detrimental effects on care are to be avoided.  相似文献   
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BACKGROUND: To describe the ultrasound biomicroscopic (UBM) features of anterior segment cysts. DESIGN: A retrospective case series. PARTICIPANTS: One hundred eighteen eyes with anterior segment cysts examined by UBM at The New York Eye and Ear Infirmary between August 1992 and November 1997 were included in this study. INTERVENTION: The authors reviewed demographic and diagnostic data from the medical record including ocular and medical history, age, race, gender, and intraocular pressure. Ultrasound data concerning the type, number, position, and acoustic characteristics of cysts were recorded. The authors then correlated the written, clinical, and UBM characteristics. RESULTS: One hundred eyes (92.6%) had neuroepithelial cysts. Ninety (83.3%) of these had primary neuroepithelial cysts, 10 (9.3%) had cysts associated with uveitis, 7 (6.5%) had implantation cysts, and 1 (0.9%) had a cavitated ciliary body tumor. Neuroepithelial cysts typically were round or ovoid, thin-walled, and echolucent. Of the 90 eyes with primary neuroepithelial cysts, 56 (62.2%) had 3 or fewer cysts; multiple cysts (>3 per eye) were found in 34 eyes (37.8%). The multiple cysts occupied more than 180 degrees in 12 patients (13.3%). Primary neuroepithelial cysts were located at the iridociliary junction (74.2%), pars plicata (14.0%), pars plana (6.8%), and iris (5.0%). Implantation cysts (seven eyes) tended to have thicker walls and two contained a copious, echogenic material. CONCLUSION: The UBM results provide important information regarding location and extent of anterior segment cystic lesions. Ultrasound characteristics may help differentiate between neuroepithelial, implantation, and neoplastic cysts.  相似文献   
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