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41.
Stephens RW; Golder JP; Fayle DR; Hume DA; Hapel AJ; Allan W; Fordham CJ; Doe WF 《Blood》1985,66(2):333-337
Adherent monolayer cultures of human blood monocytes, peritoneal macrophages, bone marrow macrophages, and colonic mucosa macrophages were examined for their ability to produce and secrete minactivin, a specific inactivator of urokinase-type plasminogen activator. All except colonic mucosa macrophages produced and secreted appreciable amounts of minactivin, but only blood monocytes were stimulated by muramyl dipeptide (adjuvant peptide) to increase production. The minactivin from each of these populations could be shown to preferentially inhibit urokinase-type plasminogen activator and not trypsin, plasmin, or "tissue"-type plasminogen activator (HPA66). A plasminogen-activating enzyme present in monocyte cultures appeared unaffected by the presence of minactivin and could be shown to be regulated independently by dexamethasone. 相似文献
42.
The biochemical and clinical consequences of 2'-deoxycoformycin in refractory lymphoproliferative malignancy 总被引:4,自引:1,他引:4
Grever MR; Siaw MF; Jacob WF; Neidhart JA; Miser JS; Coleman MS; Hutton JJ; Balcerzak SP 《Blood》1981,57(3):406-417
A deficiency of adenosine deaminase, an enzyme important in purine nucleoside catabolism, is associated with a severe combined immunodeficiency disease in children. Inhibition of this enzyme in vitro and in vivo results in an impairment in lymphoblast proliferation. We have investigated the pharmacologic inhibition of this enzyme by 2'-deoxycoformycin in 15 patients with hematologic malignancies. Biochemical consequences of the administration of this agent were closely monitored in erythrocytes, nucleated peripheral blood and bone marrow cells, serum, and urine. A marked rise in erythrocyte dATP was accompanied by a depletion of ATP in those patients exhibiting toxicity. Most patients excreted large amounts of deoxyadenosine but not adenosine in the urine. Serum deoxyadenosine rose in patients demonstrating a marked decrease in cell mass. The biochemical disturbances and clinical toxicity, including hepatic, renal, and conjunctival abnormalities, were usually reversible. Central nervous system toxicity, which potentially was the most serious consequence, was associated with high erythrocyte dATP/ATP ratios and high levels of cerebrospinal fluid deoxyadenosine. In patients with lymphoma and leukemia, objective responses were observed but were short- lived. Patients with chronic lymphocytic leukemia receiving weekly low doses of the drug demonstrated minimal toxicity and some efficacy. The chemotherapeutic potential o 2'-deoxycoformycin, as either a single agent or in combination with Ara-A, merits further exploration. 相似文献
43.
M Schweigert N Solymosi A Dubecz M Beron L Thumfart D Oefner-Velano HJ Stein 《Annals of the Royal College of Surgeons of England》2012,94(5):331-335
INTRODUCTION
Parapneumonic pleural empyema is a critical illness. Age is an acknowledged risk factor for both pneumonia and pleural empyema. Furthermore, elderly patients often have severe co-morbidity. In the case of pleural empyema, their clinical condition is likely to deteriorate fast, resulting in life threatening septic disease. To prevent this disastrous situation we adapted early surgical debridement as the primary treatment option even in very elderly patients. This study shows the outcome of surgically managed patients with pleural empyema who are 80 years or older.METHODS
The outcomes of 222 consecutive patients who received surgical therapy for parapneumonic pleural empyema at a German tertiary referral hospital between 2006 and 2010 were reviewed in a retrospective case study. Patients older than 80 years were identified.RESULTS
There were 159 male and 63 female patients. The mean age was 60.5 years and the overall in-hospital mortality rate was 7%. Of the 222 patients, 37 were 80 years or older (range: 80–95 years). The frequencies of predominantly cardiac co-morbidity and high ASA (American Society of Anesthesiologists) grades were significantly higher for very elderly patients (p<0.001). A minimally invasive approach was feasible in 34 cases (92%). Of the 37 patients aged over 80, 36 recovered while one died from severe sepsis (in-hospital mortality 3%). There was no significant difference in mortality between the very elderly and the younger sufferers (p=0.476).CONCLUSIONS
Early surgical treatment of parapneumonic pleural empyema shows excellent results even in very elderly patients. Despite considerable co-morbidity and often delayed diagnosis, minimally invasive surgery was feasible in 34 patients (92%). The in-hospital mortality of very elderly patients was low. It can therefore be concluded that advanced age is no contraindication for early surgical therapy. 相似文献44.
Zollikofer CL; Cragg AH; Einzig S; Castaneda-Zuniga WR; Castaneda F; Rysavy JA; Bruhlmann WF; Shebuski RJ; Amplatz K 《Radiology》1983,149(3):681-685
To prevent platelet aggregation following percutaneous transluminal angioplasty (PTA), cyclooxygenase inhibitors such as acetylsalicylic acid (ASA) and indomethacin are recommended. However, ASA blocks both the proaggregating effects of thromboxane (TXA2) and the antiaggregating and vasodilating effects of prostacyclin (PGI2). The authors measured the contractile response of dilated canine carotid arteries in situ and in vitro using an isometric force transducer. Following PTA, contraction of the arterial wall was significantly reduced (p less than 0.01). By blocking cyclooxygenase with indomethacin (3 micrograms/ml), contraction was greatly improved (p less than 0.001). These results suggest that PTA may result in marked release of prostacyclin by the damaged arterial wall, which could account for the decreased responsiveness of the artery to exogenous norepinephrine. 相似文献
45.
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47.
Percutaneous transluminal angioplasty of the femoropopliteal artery: initial and long-term results 总被引:4,自引:0,他引:4
Patients with dilated stenoses and recanalized occlusions were evaluated to assess the initial and long-term results of percutaneous transluminal angioplasty (PTA) in the femoropopliteal artery. The follow-up period was at least 1 year. The initial success rate was 84% (128/164). The initial results were influenced by the radiologist's experience, catheter selection, and type of lesion. The 5- and 7-year cumulative patency rates were 70% and 60%. There was no difference in long-term patency between initially successful stenoses and short (less than 3 cm) occlusions. Both the morphology and location of the stenotic lesion influenced the long-term results. Although many factors influence the initial and long-term success rate, results of this study justify PTA in the femoropopliteal artery. Patients with localized stenoses and short occlusions are best suited for this treatment. 相似文献
48.
49.
Triple-balloon dilation (TBD) of a variety of luminal structures has been successfully, though infrequently, used. A mathematical model is presented for the selection of balloon sizes, and equations and tables are derived that allow the user to estimate more accurately the size of balloons needed for TBD of structures with large lumina. With TBD, an approximately circular lumen can be formed. Also, TBD allows smaller, higher-pressure balloons to be used instead of single, low-pressure, large balloons. However, multiple puncture sites may be required for TBD. 相似文献
50.
Gray-scale ultrasonography of the normal female pelvis 总被引:5,自引:0,他引:5