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91.
Any type hemorrhagic manifestation may occur 12 hours to 5 weeks after the administration of beta-lactam antibiotics. The mechanisms of blood losses proved to be by: 1) immunologic thrombocytopenia (penicillins); 2) alteration of platelet functions (semisynthetic penicillins); 3) hypoprothrombinemia (cephalosporins). The risk factors for the occurrence of hemorrhage under beta-lactam antibiotics therapy are: concomitant administration of cytostatics for a neoplastic malignancy; b) acute or chronic renal failure; c) concomitant treatment for duodenal and gastric ulcer; d) malnutrition; e) dosage and duration of antibiotic administration. The frequency of bleeding under beta-lactams is not determined as yet. A severe case diagnosed at the IIIrd Medical Clinic of Iasi presenting spontaneous daily nasal bleedings that occurred 24 hours after the initiation of the treatment with cephalosporins (Kefurox) is presented. In this patient the risk factor was chronic renal failure.  相似文献   
92.
Comparative data on the mechanical properties of epidural catheters used clinically are not available. We performed a controlled laboratory investigation to assess the mechanical performance of three different intact or traumatized catheter types (Polyurethane, clear nylon, and radiopaque nylon catheters, designed for 18-gauge Tuohy needles). We studied a control (intact) and two trauma groups (needle bevel and surgical blade). Catheters were loaded to their breaking points by using a Lloyd LS500 material testing machine (Lloyd, Southampton, UK). Maximal load and extension values before breakage were measured, and modulus of elasticity and toughness values were calculated. Intact polyurethane catheters did not break within the limits of the experimental study (extension up to 3 times the original length of a specimen). The toughness values obtained from polyurethane and clear nylon catheters were significantly higher than those for the radiopaque catheters in intact specimens (P < 0.05). In the traumatized groups, polyurethane catheters had the highest toughness values (P < 0.05). Modulus of elasticity values were higher in both control and trauma groups of the radiopaque catheters when compared with the polyurethane and clear nylon catheters, which indicates a higher stiffness to elastic deformation (P < 0.05). In conclusion, polyurethane catheters are the most durable catheter type to tensile loading, either intact or traumatized. Mechanical properties can be used to predict complications related to the clinical use of these catheters. IMPLICATIONS: Using a computer-assisted material testing machine, we studied the mechanical properties of three different types of epidural catheters, either intact or traumatized, in a blinded, controlled study. This information may be vital to clinicians who implant epidural catheters by helping them choose a catheter that has the lowest probability of failure.  相似文献   
93.
BACKGROUND: The study was aimed to evaluate the analgesic efficacy, postoperative comfort, recovery characteristics and side effects of three different analgesic agents administered prophylactically. METHODS: Eighty patients undergoing day-case minor operative laparoscopy were randomly allocated into four groups to receive tenoxicam 20 mg i.v. (Group T), fentanyl 100 microg i.v. (Group F), 5 ml of bupivacaine 2.5 mg/ml for infiltration of trocar sites (Group B), 30, 10 and 5 min before incision respectively. Bupivacaine, 35 ml, 2.5 mg/ml was also administered into the pelvic cavity in Group B. Group P received only placebo. Postoperative pain, analgesic requirements, first response to verbal stimulus, first analgesic requirement, ability to walk without help, to drink and to void, blood pressures, SpO2 and respiration rates were recorded in the PACU. Postoperative pain was evaluated by verbal rating scale. Pain scores, analgesic requirements and side effects were evaluated by telephone calls until the 48th postoperative hour. RESULTS: Postoperative pain scores were lower and time to requirement of rescue analgesics was longer in groups F and B compared to Group P. In the PACU, analgesic requirements were lower in Group B, compared to Group P. Nausea and vomiting were increased in Group F. CONCLUSION: Tenoxicam 20 mg i.v. was found to be ineffective whereas bupivacaine was superior to other groups in reducing pain and analgesic requirements. Bupivacaine also increased time to first analgesics and obtained better recovery characteristics, underlining its value in prophylactic pain management compared to the other two agents.  相似文献   
94.
95.
Summary  The aim of this study is to find out the effects of different doses of midazolam, when used epidurally, on somatosensory evoked potentials (SEP) by delaying neuronal conduction. Thirty two New Zeland albino male rabbits were divided into four groups. All rabbits were anesthetised with ketamine and xylasine combination and atracurium was used as muscle relaxant. 10 mg/kg/hr ketamine infusion was used for maintenance of anesthesia. After insertion of the epidural catheter surgically; Group 1 received 1.5 ml isotonic saline (Control), Group 2 received 150 μg/kg, Group 3 received 250 μg/kg, and Group 4 received 500 μg/kg midazolam epidurally. With the stimulation of sciatic nerve, SEP records were recorded from the epidural space. Records were received before the injection of the drug, and 20, 40, 60 minutes after injection of the drug.  “Latancy” results were increased according to control in all groups (including isotonic saline-control-group). Increase in latancy in the control group was interpreted as due to the effect of temperature mismatch of the saline and the rabbits. While in the first and second group amplitudes showed no differences, group 3 and 4 showed decreases of up to 50%. Epidurally administered midazolam up to 150 μg/kg caused no change in SEP records, but 250 and 500 μg/kg doses caused decreases in SEP records which can lead to misinterpretation as neurological damage.  相似文献   
96.
PURPOSE: We evaluate the effectiveness of deep dorsal vein embolization for the treatment of venous impotence. MATERIALS AND METHODS: A total of 32 impotent patients with veno-occlusive dysfunction underwent deep dorsal vein embolization. The condition was suspected based on findings of penile Doppler ultrasonography and cavernosometry. The diagnosis was confirmed with pharmacocavernosography that appeared to delineate venous leakage. During the procedure we isolated and cannulated the deep dorsal vein through a small dorsal penile incision with the patient under local anesthesia. We used a mixture of the tissue glue, N-butyl cyanoacrylate, and lipodol for embolization, with a total volume of 5 ml. injected antegrade into the previously catheterized dorsal vein under fluoroscopic control. As soon as we observed the occluded veins we performed repeat pharmacocavernosography. At 3-month followup patients were reassessed with history and cavernosometry. Followup ranged from 12 to 36 months (median 25). RESULTS: Of 32 patients 22 (68.7%) regained sexual activity, which was confirmed by cavernosometry. The remaining 10 patients (31.3%) experienced little if any clinical response, which correlated with cavernosometry. There were no significant side effects. CONCLUSIONS: Deep dorsal vein embolization for venogenic impotence is simple, effective and safe, and appears to be cost-effective. The results obtained in this limited number of patients are promising and justify trials in larger groups.  相似文献   
97.
OBJECTIVE: Hydatid disease is a parasitosis and endemic in many sheepraising areas; it is still an important health problem in Turkey. We report our experience with childhood hydatid cyst and discuss the concepts of treatment. METHODS: The clinical courses of 128 children with thoracic and liver hydatid cyst operated on from 1994 to 2000 were reviewed. The group consisted of 71 boys and 57 girls aged from 8 months to 16 years. Intact cysts were found in 144 patients and ruptured cysts in 68. RESULTS: In the postoperative course we have encountered 20 perioperative complications in 16 patients. The most common complication was residual pleural space and delayed air leakage, which occurred in 9 patients. There was no early death. CONCLUSION: Surgery is the treatment of choice for most patients with pulmonary hydatid disease. The aim of surgery is evacuation of the cyst, removal of the endocyst, and management of the residual cavity. Conservative surgical methods that preserve lung parenchyma should be preferred.  相似文献   
98.
BACKGROUND: Coronary bypass surgery that provides good long-term graft patency can be performed on the beating heart as a viable alternative to conventional coronary artery bypass grafting (CABG). METHODS: From September 1993 to December 1996, 696 patients underwent CABG on the beating heart at the Ko?uyolu Heart and Research Hospital in Istanbul. Among them, 70 patients were chosen randomly for angiographic assessment of off-pump coronary artery bypass grafting. RESULTS: The interval from operation to angiography varied from 24 to 61 months (mean, 36.1+/-10.9 months). The patency rate of left internal mammary-left anterior descending artery anastomoses was 95.59% (patency achieved in 65 of 68 patients) and of vein grafts was 47.06% (patency achieved in 16 of 34 patients) (p < 0.0001). The patency rates of grafts anastomosed to the left anterior descending artery were significantly higher than the rates of the grafts anastomosed to the other coronary arteries (95.71% versus 45.45%, p < 0.0001). Multivariate analysis showed that graft type (p < 0.0001) and hyperlipidemia (p = 0.023) were significant predictors for graft occlusion. Left ventricular function improved significantly after CABG (p = 0.04). Reintervention (using percutaneous transluminal cardiac angioplasty) and reoperation rates were 0.97% and 1.4%, respectively. CONCLUSIONS: Off-pump coronary artery bypass grafting appears to produce midterm and long-term patency rates that are comparable to those of conventional techniques; that is especially true in cases of arterial conduits and of conduits anastomosed to the left anterior descending artery.  相似文献   
99.
To understand antioxidant activity and the role played by melatonin, we have designed and tested several new compounds. We present the results in terms of structure-activity relationships, focusing on the lack of the methoxy group and the influence of the amide side chain. Antioxidant activity of melatonin and some new melatonin analogue indole derivatives were investigated, using lipid peroxidation and superoxide anion radical scavenger activity assays, in rat liver tissue homogenate. Most of the compounds were found to be very potent inhibitors of malondialdehyde (MDA) formation at 10−3M. Inhibition rates ranged from 75-44 %. However, no significant inhibitory effect was obtained on superoxide anion formation. Consequently, it can be concluded that these compounds exhibit important LP activity compared to melatonin.  相似文献   
100.
A laryngocele is an air-filled dilation of the saccule of the larynx. An infected laryngocele is called a laryngopyocele. Our experience with a case of laryngopyocele with signs on computed tomography before and after antibiotic therapy is presented since laryngopyocele is more unusual.  相似文献   
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