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BACKGROUND: The clinical benefit of coronary stenting is reduced by the risk of thrombotic stent occlusion as well as hemorrhagic complications of intensive antithrombotic therapy. We compared the influence of different antithrombotic therapies on the incidence of post-interventional complications and in-hospital stay duration. METHODS: After successful placement of a coronary stent, 334 consecutive patients were given different antithrombotic treatments in addition to aspirin 100 mg/d indefinitely: (1) phenprocoumon for 3 months (n = 47), (2) low molecular weight heparin 2 x 100 U/kg/d s.c. for 4 weeks (n = 90), (3) ticlopidine 2 x 250 mg/d and low molecular weight heparin 2 x 100 U/kg/d s.c. for 4 weeks (n = 72) and (4) ticlopidine 2 x 250 mg/d for 4 weeks (n = 125). RESULTS: Major events were subacute stent thrombosis in 17 patients (5%), and severe hemorrhagic complication in 20 patients (5.9%). The incidence of subacute stent thrombosis in groups 1 to 4 was 10.6%, 11%, 1.4% and 0.8% respectively. The use of ticlopidine was associated with a significant lowering of stent occlusions in univariate and multivariate analysis (p = 0.0013). Additional uni- and multivariate predictors were stent placement as a "bail-out" procedure (p = 0.033) and in patients with acute coronary syndrome (p = 0.049). Anticoagulant therapy was associated with a higher incidence of severe hemorrhagic complications (p < 0.01) and a prolonged in-hospital stay (p = 0.01). CONCLUSIONS: These results confirm that anti-thrombotic therapy with aspirin and ticlopidine combines low rates of subacute stent occlusion and hemorrhagic complications. Treatment with phenprocoumon and low molecular weight heparin does not improve the rate of subacute stent occlusion but increases hemorrhagic complications. Very low rates of stent occlusion permit short in-hospital stays with concomitant reduction in cost.  相似文献   
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Bypass surgery for vascular disease of the carotid system   总被引:2,自引:0,他引:2  
A series of 58 operations on 56 patients, in whom a branch of the superficial temporal artery was anastomosed to a branch of the middle cerebral artery (STA-MCA bypass or Yasargil procedure), is reviewed. These operations were performed chiefly for occlussions or for inaccessible stenotic lesions of the internal carotid or middle cerebral arteries. Patency in eight patients operated on from April 1971 through November 1973 was low (25%). Patency in patients operated on since July 1974 has been high (95%). There have been no deaths and no major ischemic strokes attributable to the surgery. The rationale for this procedure is considered in relationship to the anatomy and physiology of the cerebral circulation and the pathogenesis of syndromes of cerebral ischemia. The operation appears to have a low morbidity in good-risk patients. The role of this operation in managing common manifestations of cerebral vascular disease such as focal transient cerebral ischemic attacks (TIAs) and amaurosis fugax, although not fully established, appears encouraging. The procedure seems useful for orthostatic cerebral ischemia caused by multiple occlusions of major extracranial (and intracranial) vessels and, occasionally, for progressing strokes related to internal carotid artery occlusion, both of which are relatively uncommon manifestations of cerebral vascular occlusive disease. It may have application in the rare "slow stroke." The procedure is probably of limited value, if any, in the management of large completed infarcts but may be indicated in selected patients with small infarctions who have preserved most of their cerebral function and who have had evidence of subsequent focal ischemic events. The procedure is useful for bypassing giant aneurysms or basofrontal tumors invading major vessels. It may have a role in the management of fibromuscular disease of the internal carotid artery.  相似文献   
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AIM: The aim of this study was early differentiation between uncomplicated and complicated processes of healing in the jaw using bone SPECT. METHODS: Investigations were performed in 40 mandibular fractures and 26 jaws after onlay osteoplasty as well as secondary insertion of implants. Bone SPECT was carried out within 1-2 months and after approximately 4-5 months. The uptake in the jaw was assessed semi-quantitatively using ROI analysis. RESULTS: Fractures with uncomplicated healing showed a decrease of uptake in follow-up, whereas fractures with an infection in the later course showed an increase, resulting in a significantly higher uptake at the follow-up investigation for the latter group. 1-2 months after onlay osteoplasty significantly lower uptake was found in regions with later occurrence of sequestration. In regions with implants in which osseointegration failed, there was significant reduction of uptake initially and significant elevation at the follow-up investigation. CONCLUSION: These results indicate a prognostic relevance of bone SPECT in the evaluation of processes of healing in the jaw.  相似文献   
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Active transport of nitrofurantoin across the mammary epithelium in vivo   总被引:1,自引:0,他引:1  
Nitrofurantoin is a commonly used urinary tract antibiotic that has been found at high concentrations in human milk. In vivo studies in rats were carried out to determine the mechanism by which this drug crosses the mammary epithelium. Lactating rats were gavage-fed with nitrofurantoin, and their milk and plasma levels of the antibiotic were measured at intervals up to 8 hr. The average milk-to-plasma (M/P) ratio, calculated from the areas under the milk and plasma curves, respectively, was 23 compared with a ratio predicted to be about 0.3 on the basis of lipid partitioning and protein binding determinations. M/P ratios for two nitrofurantoin congeners were also calculated. The neutral compound furazolidone had a M/P ratio of about 1, as predicted, whereas the basic compound furaltadone had a M/P ratio of 3.49 compared with a predicted ratio of 1.4. These data suggest that nitrofurantoin and, to a lesser extent, furaltadone are actively transported across the mammary epithelium into milk.  相似文献   
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To examine the resting and evoked release of the endogenous opioid peptides beta-endorphin and Met-enkephalin from brain, we examined the levels of the respective immunoreactivities in the lateral ventricle-cisterna magna perfusate of the halothane-anesthetized rat. Ten Hz but not 100 Hz stimulation in the arcuate nucleus (ARC) of the hypothalamus released beta-endorphin immunoreactivity (beta-EPir) to the perfusate, whereas 100 Hz but not 10 Hz stimulation in the periaqueductal gray (PAG) of the mid brain released Met-enkephalin immunoreactivity (MEir). MEir was not released by stimulation in ARC and beta-EPir was not released by stimulation in PAG. Characterization of the released beta-EPir and MEir by high performance liquid chromatography showed that authentic beta-endorphin and Met-enkephalin were the major constituents of beta-EPir and MEir, respectively. Systemic administration of the dopaminergic antagonist haloperidol increased plasma, but not perfusate levels of beta-EPir. Both the opioid antagonist naloxone and the NMDA antagonist MK-801 failed to affect beta-EPir or MEir release. ARC and PAG stimulated inhibited a nociceptive reflex (tail-dip in 52.5 degrees C water), and naloxone did not reliably reverse this inhibition. These data support the previously suggested possibility of opioid mediation of stimulation induced analgesia, although we were unable to confirm the theory by naloxone reversibility in this study. Furthermore, the data support the assumption that measurement of opioid peptides in cerebrospinal fluid is a relevant approach in research aimed at elucidating the physiological and pathophysiological roles of endogenous opioid peptides.  相似文献   
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Several features of bacteriophage lambda suit it for the study of genetic recombination. Central among them are those that make it possible to correlate inheritance of DNA with the inheritance of information encoded by DNA through density-label equilibrium centrifugation. Such studies have revealed relationships between DNA replication and recombination, have identified roles for double-strand breaks in the initiation of recombination, and have elucidated the role of the recombination-stimulating sequence, chi.  相似文献   
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