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71.
Background: Nonsteroidal anti-inflammatory drugs (NSAIDs) may interfere with hemostasis during the perioperative period, and the combination of NSAID and enoxaparin could increase this effect. The aim of this prospective, blinded experimental study was to assess these effects using a model of arterial thrombosis and bleeding in the rabbit.

Methods: After anesthesia was induced and monitors placed, the common carotid arteries were exposed, and 60% stenosis of the right common carotid artery was produced. Twenty minutes later, a compression injury of the artery was produced that triggered a series of cyclic episodes of thrombosis and clot lysis. This was manifested as cyclic flow reductions (CFR; measured with an electromagnetic flow meter). After the first flow reduction was noted, the rabbits were immediately and randomly assigned to one of four groups (n = 10 each) that received intravenous infusions: control, ketorolac (2 mg/kg), enoxaparin (0.5 mg/kg), and ketorolac plus enoxaparin (2 mg/kg and 0.5 mg/kg, respectively). The number of CFRs that occurred in the subsequent 20-min period was used as a measure of treatment effect. The contralateral common carotid artery was exposed, and both stenosis and injury were produced. The ability of the administered drug to prevent thrombosis was assessed as the number of CFRs that occurred during the first 20-min period after vessel injury. In addition, both before and after group assignment and drug injection, bleeding times were noted and a platelet aggregation test was performed. Laparotomy was followed by a spleen section, and the extent of the wound and the amount of splenic bleeding were measured.

Results: The treatment effect was indicated by the median number of CFRs, which was 5.5 in the control group, 1 in the ketorolac group, 2 in the enoxaparin group, and 0 in the ketorolac + enoxaparin group. The prevention effect was indicated by the median number of CFRs, which was 4 in the control group, 0 in the ketorolac group, 2 in the enoxaparin group, and 0.5 in the ketorolac + enoxaparin group. Bleeding time was significantly lengthened in the enoxaparin and in the ketorolac + enoxaparin groups. Splenic and wound bleeding was greater in the ketorolac group. Platelet aggregation was completely inhibited in the ketorolac and the ketorolac + enoxaparin groups.  相似文献   

72.
Transmetallation between commercially available solutions of gadolinium (Gd) chelates and the zinc (Zn)-dependent angiotensin-converting enzyme (ACE) was investigated. In vitro, the strongest inhibitions were observed for the linear Gd complexes, Gd diethylene-triamine pentaacetic acid (DTPA) bis-methylamide (BMA) (IC50 = .016 ± .006 mmol/1) and Gd-DTPA (IC50 = .350 ± .034 mmol/1). The two macrocycles Gd tetraazacyclododecane tetraacetic acid (DOTA) and Gd-HP-DO3A were similar and 400 times less active than Gd-DTPA-BMA. These effects were mainly due to the presence of free ligand for DTPA and calcium (Ca) chelate in the case of DTPA-BMA because the addition of Zn2+ in the same quantities suppresses their inhibitory effects. In vivo, these two solutions of linear Gd chelates significantly inhibited ACE activity (Gd-DTPA: 67 ± 9% versus baseline; and Gd-DTPA-BMA: 73 ± 2% versus baseline at the clinical dose of .1 mmol/kg), whereas no significant effect was observed for the two macrocyclic chelates Gd-DOTA and Gd-HP-DO3A. Formulating the Gd chelate solution with either an excess of free ligand or Ca chelate (to decrease Gd3+ release) in the case of linear Gd chelate may have deleterious biologic consequences.  相似文献   
73.
Summary A new liposuction cannula which can be used both with the syringe and with the machine has been produced by the author.  相似文献   
74.
Summary Up-to-date unsatisfactory results obtained in multimodality treatments of malignant glioma have prompted the research of new therapeutic modalities with unconventional modes of action. Lonidamine (LND) is a drug which reduces aerobic glycolytic activity in both human and experimental tumors. This effect mainly depends on the inhibition of mitochondrially-bound hexokinase (HK) which is present in large amounts in malignant cells. A Phase II study was conducted on patients with recurrent glioma; 12 patients were admitted to the study. Clinical side effects were moderate, necessitating a reduction of the dosage in only 1 case. The objective results were evaluated according to the indications of Levin. 2 responders and 3 cases of stable disease were observed out of 10 evaluable patients. The potential value of this new drug is discussed.  相似文献   
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76.
The improvements in the motor ability in patients with Parkinson's disease due to antiparkinsonian medication is well-known and widely documented. Recent results, based both on kinematic parameters and standard electromyographic (EMG) signal analysis, clearly indicated that the medication reduced, as expected, the clinical signs of Parkinson's disease, but did not restore agonist burst duration modulation with distance in elbow flexion movements. The main aim of the present work is to shed more light on this medication effect using a wavelet analysis approach on multiple EMG signals recorded both on shoulder and elbow muscles in ballistic or rapid movements. The wavelet cross-correlation information allows us to evidence some important quantitative features of the EMG signals due to medication.  相似文献   
77.
OBJECTIVE: The objective of this study was to analyze the autonomic functions of patients with erythrophobia. METHODS: Forty patients with a diagnosis of erythrophobia (female/male ratio 18/22) without any other organic lesions and 20 healthy volunteers (female/male ratio 10/10) were assessed. Clinical evaluation was performed using a modified version of semistructured interviews. Autonomic testing was performed by means of spectral analysis of heart rate and continuous blood pressure by sparse discrete Fourier transformation at rest and under mental stress. RESULTS: There were no significant difference between the two samples in age, sex distribution, BMI, resting systolic, or diastolic blood pressure, nor was there a difference in autonomic baseline functioning between the 40 patients with erythrophobia and the control subjects. On the other hand, patients with erythrophobia consistently showed higher pulse rates (88 +/- 20 vs. 78 +/- 9 bpm, p <.05), higher total heart rate power values (8.40 +/- 0.63 vs. 8.07 +/- 1.02 p <.05), higher midfrequency spectral values (7.38 +/- 0.66 vs. 7.02 +/- 1.18, p <.01), higher high-frequency spectral values (6.89 +/- 0.86 vs. 6.48 +/- 1.44, p <.05), and lower baroreceptor sensitivity (8.62 +/- 8.16 vs. 11.65 +/- 4.42, p <.005) than the healthy subjects. ANOVA showed a significant group interaction (p <.0001) between the samples. CONCLUSIONS: This study provides evidence for abnormal autonomic functioning in patients with erythrophobia when under mental stress.  相似文献   
78.
As part of the characterization of the host reactivity to the venom ofBothrops asper, we investigated the inflammatory responses in the mouse footpad model. The subcutaneously injected venom induced a rapid increase of serum IL-6 concentration, which peaked between 3 and 6 h and returned to normal values at 12 h. In contrast, serum TNF- and IL-1 were not detectable at any time point studied. A myotoxic phospholipase A2 isoform purified from this venom, myotoxin II, was also able to induce a systemic IL-6 release when injected into the footpad. Both venom and myotoxin induced local edema and a leukocyte infiltrate accumulating in the muscle and subdermal tissue within 6 h. The infiltrate consisted predominantly of neutrophils at 6 and 24 h, but at later times, mononuclear cells also appeared. The edema, leukocyte infiltration, and IL-6 responses did not depend on the hemorrhagic activity of venom, since all three effects were seen after injection of (1) preneutralized venom, devoid of hemorrhagic activity, and (2) purified myotoxin II. Circulating platelet numbers were significantly decreased 30 min after venom injection and returned to normal after 12 h. The venom also induced a rapid inversion in the ratio of neutrophils to lymphocytes in peripheral blood, which did not normalize until 12 h later. The present observations suggest that venom, besides its cytotoxic properties, induces early hematologic and immunologic alterations. These findings may be of relevance in future treatment modalities.  相似文献   
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