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31.
A prospective randomized study was carried out on a total of 686 patients who underwent vaginal or abdominal hysterectomy. Of these, 338 were given prophylactic cefotetan (2 g) and 348 piperacillin (2 g). Both drugs were administered as i.v. bolus 30 min before operation. Findings confirm the higher risk of infection with abdominal hysterectomy and the advantages of the long half-life cephalosporin, cefotetan.  相似文献   
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Naloxone, an opioid peptide antagonist, has been reported to facilitate voiding in neurologic bladder disorders, but its effects on the neural micturition reflex arc are poorly understood. We studied the effect of naloxone in 34 male adult cats, spinalized at C5-C6 level 7 to 119 days previously. Each cat served as its own control. The following tests were performed: Urethral pressure profiles, cystosphincterograms with the urethro-vesical junction opened and closed and mechanograms of the detrusor, and the circular and longitudinal urethral muscles. The study included (1) the effects of anesthesia of the bladder and pelvic nerve, as well as that of the urethral and pudendal nerves; (2) the action of naloxone; and (3) the action of oxymorphone. Our results demonstrated that naloxone (1) increased somatic (osteotendinous and nociceptive) reflexes and aggravated spasticity; (2) increased vegetative micturitional and sexual reflexes, in particular the urethra-urethral contraction reflex, aggravating the spasmodic contractions of the external sphincter; and (3) increased the frequency and intensity of the mass reflex. In consequence, we suggest that naloxone is contraindicated in cases of spinal cord lesions with detrusor-sphincter dyssynergia syndrome.  相似文献   
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Vitamin E biokinetics, oxidative stress and cigarette smoking.   总被引:2,自引:0,他引:2  
Vitamin E is comprised of four tocopherols and four tocotrienols, and functions as a lipophilic chain-breaking antioxidant that prevents lipid peroxidation. Although it is well recognized that cigarette smoke is source of oxidative stress, relatively little is known regarding how oxidative stress alters vitamin E utilization in humans. Therefore, this review will highlight the recent knowledge regarding how cigarette smoking alters vitamin E (as alpha- and gamma-tocopherols) utilization in humans. Specifically, we will discuss the mechanisms by which cigarette smoking increases the turnover of plasma vitamin E, decreases the P450-mediated metabolism of vitamin E, and increases the nitration of gamma-tocopherol to result in the formation of 5-nitro-gamma-tocopherol. In addition, the interrelationship between oxidative stress and vitamin C will also be emphasized as it relates to vitamin E utilization.  相似文献   
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OBJECTIVE: Biventricular pacing has demonstrated improvement in cardiac function in treating congestive heart failure (CHF). Two different operative strategies (coronary sinus vs. epicardial stimulation) for left ventricular (LV) pacing were compared. METHODS: Since April 1999, a total of 86 patients (pts, age: 63+/-10 years) with depressed systolic LV function (mean ejection fraction 24+/-9%), left bundle-branch-block (mean QRS 182+/-22 ms) and congestive heart failure NYHA III or higher were enrolled. For biventricular stimulation coronary sinus (CS) leads were placed in 79 pts. Nine of these devices were converted to surgical epicardial LV-leads, because of CS-lead failure. In 7 patients epicardial LV-leads were initially implanted surgically, accounting for a total of 16 pts with surgical placed epicardial steroid-eluting LV-leads. For these, a limited left-lateral thoracotomy (7+/-4 cm) was used. Thirty-three (38%) pts had an indication for a defibrillator. The mean follow-up time was 16.4+/-15.4 months (0.1-45 months), representing 107.1 patient-years. RESULTS: In the biventricular pacing mode, QRS duration decreased to 143+/-16 ms (P<0.001). Threshold capture of the CS-leads increased significantly compared to surgically placed epicardial leads (18 month control: 2.2+/-1.4V/0.5 ms vs. 0.7+/-0.3V/0.5 ms), which had no increase in threshold (P<0.001). At the 18 month follow-up 7 CS-leads had a threshold of >4V/0.5 ms vs. epicardial leads which were under 1.1V/0.5 ms, except for one (1.8V/0.5 ms). After CS-lead implantation 25 LV-lead related complications occurred, (failed implantation, CS-dissection, loss of pacing capture, diaphragm stimulation or lead dislodgment), vs. one dislodgement after surgical epicardial lead placement (P<0.05). Correct lead positioning (obtuse marginal branch area) was achieved in all surgical epicardial placements but only in 70% with CS-leads (P<0.03). In the follow up period, 9 pts died (4 cardiac related). Heart transplantation was necessary in 4 pts due to deterioration of the cardiomyopathy. CONCLUSIONS: Surgical epicardial lead placement revealed excellent long-term results and a lower LV-related complication rate compared to CS-leads. Although, the approach via limited thoracotomy for biventricular pacing is associated with 'more surgery', it is a safe and reliable technique and should be considered as an equal alternative.  相似文献   
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The occurrence of transitory cognitive impairment during diffuse subclinical electroencephalographic (EEG) discharges has been widely documented but the role of the parameters influencing the cognitive performance and the involvement of motor or verbal response in the tasks used is still under debate. Fifteen patients suffering from primary generalized epilepsy with frequent bisynchronous EEG epileptic bursts underwent a shape recognition task during EEG monitoring. The test sequence was as follows: memorandum, pause, and multiple choice set. After pressing the response button, the patient was asked to confirm the choice verbally. The following parameters were considered: geometrical complexity of the shape, chronological position of the burst occurring during the single test, and the duration of discharge ranging from 1 to 3 s. Results showed a significant increase in incorrect responses during the test when discharges occurred, with more errors occurring for difficult than for easy shapes. Neither the discharge position nor the duration of the epileptic burst influenced the performance. Diffuse epileptic activity of short duration produced selective effects on the cognitive process regardless of the motor component of the response.  相似文献   
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BACKGROUND: Chronic kidney disease patients who are resistant to erythropoietin (EPO) treatment may suffer from malnutrition and/or inflammation. METHODS: In a cross-sectional study of haemodialysis patients, we investigated the relationship between the natural logarithm of the weekly EPO dose normalized for post-dialysis body weight and outcome measures of nutrition and/or inflammation [BMI, albumin and C reactive protein (CRP)] by means of multiple linear regression analysis. On the basis of the decile distribution of weekly EPO doses, we also evaluated four groups of patients: untreated, hyper-responders, normo-responders and hypo-responders. RESULTS: Six hundred and seventy-seven adult haemodialysis patients were recruited from five Italian centres. BMI and albumin were lower in the hypo-responders than in the other groups (21.3+/-3.8 vs 24.4+/-4.7 kg/m(2), P<0.001; and 3.8+/-0.6 vs 4.1+/-0.4 g/dl, P<0.001), whereas the median CRP level was higher (1.9 vs 0.8 mg/dl, P = 0.004). The median weekly EPO dose ranged from 30 IU/kg/week in the hyper-responsive group to 263 IU/kg/week in the hypo-responsive group. Transferrin saturation linearly decreased from the hyper- to hypo-responsive group (37+/-15 to 25+/-10%, P = 0.003), without any differences in transferrin levels. Ferritin levels were lower in the hypo-responsive than in the other patients (median 318 vs 445 ng/ml, P = 0.01). At multiple linear regression analysis, haemoglobin, BMI, albumin, CRP and serum iron levels were independently associated with the natural logarithm of the weekly EPO dose (R(2) = 0.22). CONCLUSIONS: Our findings support a clear association between EPO responsiveness and nutritional and inflammation variables in haemodialysis patients; iron deficiency is still a major cause of hypo-responsiveness.  相似文献   
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A method of graphic representation of time factors in cancer mortality is presented, based on different tonalities of grey applied to the surface of the matrix defined by various age-specific rates. It is illustrated using mortality data from cancers of the mouth or pharynx, oesophagus, larynx and lung in Italian and Swiss males. Progressively more complex regression surface equations are defined, on the basis of two independent variables (age and cohort) and a dependent one (each age-specific rate). General patterns of trends were thus identified, showing important similarities in cohort and period effects, but also noticeable differences in time-related factors in mortality from various neoplasms of the upper digestive and respiratory tract. For instance, there were declines in mortality from cancers of the mouth or pharynx in the oldest age groups, whereas rates were appreciably upwards at younger and middle age, particularly in Italy. Likewise, cancers of the oesophagus and, chiefly, of the larynx were substantially increasing, on a cohort basis, in oldest Italian males. Temporal pattern for laryngeal cancer in Italy was similar to that of lung cancer, thus suggesting that (cigarette) smoking has a greater impact on this cancer site as compared with alcohol. However, it is difficult to explain, on this basis alone, the totally diverging pattern for cancer of the larynx (downwards) and of the lung (upwards) observed among older Swiss males. These examples indicate that trend surface models are a useful summary guide to illustrate and understand the general patterns of age, period and cohort effects in cancer mortality.  相似文献   
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