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91.
Plasma tumor necrosis factor and mortality in critically ill septic patients   总被引:23,自引:0,他引:23  
Tumor necrosis factor (TNF) cachectin has been implicated as an important host mediator responsible for shock and multiple organ failure (MOF) observed during sepsis. Using a sensitive enzyme-linked immunosorbent assay, we measured plasma TNF levels in 43 septic patients suffering from a broad range of diseases. Measurements were taken on the day that sepsis was diagnosed. Eleven patients had detectable TNF plasma levels ranging from 10 to 100 pg/ml (TNF-positive group); in 32 patients circulating TNF could not be detected (TNF-negative group). The groups did not differ significantly as to age, underlying disease, percentage positive bacteremia and bacteriologic profile, sepsis score, and extent of MOF. Eight (73%) of 11 TNF-positive patients died from sepsis during ICU stay, vs. 11 (34%) of 32 TNF-negative patients (p less than .05). This study demonstrates that sepsis is accompanied by detectable circulating TNF in 25% of the cases, and for these patients mortality is twice that for comparable TNF-negative patients.  相似文献   
92.
Up to now two abnormal nephrographic patterns have been described as a result of arterial hypotension as an adverse response to urographic contrast material. We would like to describe a third pattern.  相似文献   
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Pharmacokinetics of the cis-platin analog ethylenediaminemalonatoplatinum(II) (JM-410) was studied in 28 cycles of 19 patients during the phase I study of this drug. The drug was administered intravenously by short-term (10-60 min) infusion. Doses ranged from 20 to 1,200mg m-2. JM-40 was determined in plasma ultrafiltrate and urine by HPLC. Platinum (Pt) concentrations were determined in plasma, plasma ultrafiltrate, urine and red blood cells by atomic absorption spectrometry up to 5 days after administration of the drug. Ultrafilterable Pt could be determined up to 45 days after the infusion in one patient sampled over such a long period. Pharmacokinetics of JM-40 showed a linear behaviour. The final half-life of total Pt in plasma was 4.1 +/- 0.9 days. The disposition of JM-40 was similar to that of ultrafilterable Pt in respect to t1/2 alpha (10 and 13 min), t1/2 beta (44 and 57 min), volumes of distribution Vc (11 and 121) and Vss (17 and 201), systemic clearance (256 and 223 ml min-1), renal clearance (69 and 73 ml min-1) and metabolic clearance (183 and 154 ml min-1). During the first 6 h 27 +/- 9% of the administered dose was excreted as JM-40. Cumulative platinum excretion in the urine amounted to 29 +/- 13% and 60 +/- 13% over the first 6 h, 24 h and 5 days, respectively. The uptake of platinum in red blood cells was limited, comprising only 0.24 +/- 0.12% of the administered dose. Although JM-40 and carboplatin are structurally closely related, pharmocokinetics and toxicity of JM-40 were more similar to cis-platin than to carboplatin.  相似文献   
95.
The simultaneous determination of cerebrospinal fluid (CSF) and plasma adenosine deaminase (ADA) activity was evaluated as a diagnostic aid in tuberculous meningitis (TBM). CSF and plasma ADA activity were determined in four groups of patients: (i) a 'no meningitis' group of 174 children investigated for possible meningitis, but found to be uninfected; (ii) an aseptic meningitis group of 40 children; (iii) a bacterial meningitis group of 31 children; and (iv) a TBM group of 27 patients (24 children and 3 adults). CSF ADA alone was determined in a further 23 children with aseptic meningitis, 19 with bacterial meningitis and 13 children and 7 adults with TBM. Both the CSF/plasma ADA ratio and the absolute CSF ADA activity were raised in TBM (mean values 0,24 and 12,61 U/I respectively) and bacterial meningitis (mean values 0,59 and 15,43 U/I respectively), but not in the aseptic meningitis group (mean values 0,06 and 2,00 U/I) or the 'no meningitis' group (mean values 0,04 and 1,51 U/I). Both values will distinguish TBM from aseptic meningitis, but do not appear to hold any marked advantages over conventional CSF criteria in the diagnosis of TBM.  相似文献   
96.
Summary In this work, we have studied the time-course of the effects of pharmacological administration of ovarian steroids on tyrosine hydroxylase (TH) activity in the limbic forebrain of ovariectomized rats. Administration of estradiol produced a late decrease in TH activity. This effect was found 24 hours after the last steroid injection, disappearing at 32 hours. It was antagonized by progesterone, since a single injection of this steroid to estradiol-pretreated rats reversed to control values the estradiol-induced decrease. Nevertheless, the administration of progesterone after estradiol treatment caused a short-time decrease in the limbic activity of TH, which was observed 4 hours after the last steroid injection, disappearing subsequently. On the other hand, the administration of progesterone alone produced a biphasic effect, with a reduction at 24 hours, followed by an increase at 32 hours. These effects were only observed in the animals non-treated with estradiol, disappearing with a previous treatment with estrogens. Hence, it can be concluded that both ovarian steroids may affect the limbic TH activity. Thus, estradiol produced a late inhibitory effect on the activity of this enzyme, which was antagonized by progesterone. Administration of the last one to estradiol-treated rats produced a short-time inhibitory effect, whereas its administration to non-treated rats produced a late biphasic effect (inhibition followed by stimulation), which was not observed in estradiol-treated rats.  相似文献   
97.
Endothelial cell seeding may improve the patency of synthetic vascular grafts provided that platelet reactivity of nonendothelialized sites is not increased. We have investigated if surface-adsorbed monoclonal antibodies directed against endothelial cell membrane proteins and against extracellular matrix proteins promote the adhesion and proliferation of cultured human endothelial cells, without causing platelet deposition at non-endothelialized sites. Adhesion of endothelial cells onto polyethylene coated with monoclonal antibodies directed against endothelial cell-specific membrane antigens, integrin receptors and glycoprotein CD31 was equal to or higher than adhesion onto fibronectin-coated polyethylene. Endothelial cells did not proliferate on these surface-adsorbed antibodies. However, pre-coating of polyethylene with mixtures of endothelial cell-specific monoclonal antibodies and monoclonal antibodies directed against fibronectin or von Willebrand factor, resulted in relatively high adhesion and optimal proliferation. Platelet reactivity of the polyethylene surface was found to significantly increase after adsorption of fibronectin, endothelial cell-specific monoclonal antibody or its Fc fragments. In contrast, adsorption of F(ab')2 fragments of endothelial cell-specific monoclonal antibody did not promote platelet deposition. Therefore, it is concluded that coating of vascular graft materials with mixtures of F(ab')2 fragments of monoclonal antibodies specifically directed against endothelial cells and against extracellular matrix proteins may be an effective way to both promote the growth of seeded endothelial cells and limit platelet-graft interaction.  相似文献   
98.
The efficacy of an instructional videotape about the interpretation of the plantar response was evaluated during a two week neurological clerkship. Experimental groups saw the videotape, control groups did not. All students (n = 65) assessed plantar responses of two to four different patients. Their judgment was compared with that of one senior neurologist. Only the students who had seen the videotape showed a significant improvement in performance on a second test (t-test, t = -2.26, p = 0.031). In addition, these students more frequently took account of the flexion synergy (Fisher exact test, p less than 0.001). Video can be an efficient tool in medical education.  相似文献   
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