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101.
The aim of this study was to compare the efficacy of sildenafil and continuous positive airway pressure (CPAP) in men with erectile dysfunction (ED) and obstructive sleep apnea syndrome (OSAS). In all, 30 men were randomly treated for 12 weeks either with sildenafil 100 mg before intercourse (15 men) or CPAP during night time sleep (15 men). Under sildenafil, 97/180 (53.9%) of attempted intercourses were successful compared to 33/138 (23.9%) under CPAP. The mean IIEF (erectile function domain score) was 12.9 and 9.3 after sildenafil and CPAP treatment, respectively (P=0.007), compared to 7.9 and 7 at baseline. In all, 53.3% of patients were satisfied with sildenafil and 20% with CPAP for ED treatment (P=0.058). Although sildenafil was superior to CPAP, comorbidities and OSAS per se possibly resulted in a lower effectiveness of sildenafil compared to that in the general population of ED men. While about half of the patients were not satisfied even with the more effective treatment, we conclude that a combination of the two therapeutic tools or a different therapeutic mode should be studied further.  相似文献   
102.
Drug addiction is characterized by drug-induced positive affect, followed by withdrawal-associated negative affect. Such drug-induced positive and negative affective states provide crucial sources of motivation that drive compulsive drug consumption. Metabotropic glutamate (mGlu) receptors, which are responsible for slow glutamate-mediated neurotransmission, are located throughout limbic and cortical brain regions that are implicated in drug addiction. Emerging evidence indicates that mGlu receptors regulate many behavioral actions of addictive drugs. In particular, group I mGlu receptors play an important role in regulating the reinforcing effects of drugs of abuse. Furthermore, group II mGlu receptors have been implicated in the synaptic adaptations that occur in response to chronic drug exposure and contribute to the aversive behavioral syndrome observed during withdrawal. These findings increase our understanding of the pathological processes that are associated with the development of drug addiction, and might ultimately lead to new therapies for the treatment of this disorder.  相似文献   
103.
Rationale Previous work has indicated a potential role for -aminobutyric acid-B (GABAB) receptor agonists in treating drug addiction in humans. Specifically, GABAB receptor agonists decreased cocaine, heroin and nicotine self-administration in rats.Objectives The purpose of the present studies was to extend previous findings by assessing the effects of additional GABAB receptor agonists on nicotine self-administration and food-maintained responding, under both fixed and progressive ratio schedules in rats.Methods Male Wistar rats were exposed to a progressive ratio schedule where various nicotine doses were made available according to a within-subjects Latin Square design. Additional groups of rats were used to test the effects of the GABAB receptor agonists baclofen and CGP44532 on nicotine self-administration (0.01 and 0.03 mg/kg per infusion) and food-reinforced responding on fixed and progressive ratio (CGP44532 only) schedules.Results Nicotine maintained stable self-administration under a progressive ratio schedule with a linear dose-response function (r=0.61). Both CGP44532 and (–)baclofen dose-dependently reduced nicotine self-administration on the fixed ratio schedule, and also decreased food-maintained responding at higher doses. Further, CGP44532 decreased breakpoints for nicotine and food at identical doses under the progressive ratio schedule.Conclusion The present data demonstrate that administration of GABAB receptor agonists decreased intravenous nicotine self-administration under both fixed and progressive ratio schedules of reinforcement, possibly reflecting reduced rewarding effects of nicotine. Both baclofen and CGP44532 exhibited specificity for nicotine- versus food-maintained responding on the fixed ratio schedules but not on the progressive ratio schedule (CGP44532 tested only), indicating the potential usefulness of GABAB receptor agonists as therapeutics for smoking cessation.  相似文献   
104.
Cocaine lowers brain reward thresholds, reflecting increased brain reward function. The authors investigated whether, similar to acute cocaine administration, cocaine-predictive conditioned stimuli would lower intracranial self-stimulation (ICSS) thresholds. Rats received a saline injection for 5 days, a cocaine injection (10 mg/kg) for 20 consecutive days, then saline for 5 additional days. Thresholds were measured immediately before and 10 min after each injection. The initial 5 saline injections had no effect on thresholds, whereas cocaine significantly lowered thresholds for 20 days. There was no tolerance or sensitization to this effect of cocaine over days. During the last 5 days when cocaine administration was substituted with saline, rats demonstrated a conditioned lowering of thresholds during the 2nd daily ICSS session. These data demonstrate that cocaine-predictive conditioned stimuli induce a conditioned facilitation of brain reward function.  相似文献   
105.
We assessed the long-term efficacy of a modified transvaginal needle bladder neck suspension, combined with vaginal hysterectomy, for the treatment of female stress incontinence. Thirty-two women who underwent this procedure were followed up clinically and urodynamically 1 and 5 years postoperatively. A total of 27 women (84.4%) were cured 1 year postoperatively. Of the 29 women who were followed up 5 years postoperatively, 21 (72.4%) had a satisfactory result (p = 0.157). No significant differences were observed in maximum urine flow rate, residual volume of urine, and functional length of the urethra. On the contrary, the maximum urethral closure pressure was significantly decreased (p = 0.004). Although the results of our study show a decline in success rate by time, the overall long-term efficacy of this technique is undoubtedly satisfactory. This technique is promising as an easy and minimally invasive surgical procedure for bladder neck suspension.  相似文献   
106.
Thromboembolic complications have been attributed to the use of radiographic contrast media (CM) during interventional procedures for arterial revascularization. However, due to the low frequency of adverse events, comparisons between different CM have been difficult to perform, although it has been suggested that ionic (vs. non-ionic) CM may be associated with fewer thrombotic events. The present study was undertaken using well-characterized baboon thrombosis models in order to compare different CM under physiologically relevant and controlled conditions of blood flow, exposure time, and CM concentration. Three CM were studied: ioxaglate, iohexol, and iodixanol. CM were locally infused into the proximal segment of femoral arteriovenous shunts. Palmaz-Schatz stents (4 mm i.d.) and expanded tubular segments (9 mm i.d.), which exhibited venous-type flow recirculation and stasis, were deployed into the shunts distally. Saline was infused in identical control studies. Blood flow was maintained at 100 ml/min. Thrombosis was measured over a blood exposure period of 2 hours by gamma camera imaging of 111In-platelets and by gamma counting of deposited 125I-fibrin. CM concentrations within the flowfield were predicted using computational fluid dynamics. At infusion rates of 0.1 and 0.3 ml/min, the low-osmolar ionic CM ioxaglate reduced both platelet and fibrin deposition on the stents by 75-80% (p <0.005), while both iohexol and iodixanol reduced platelet deposition by 30-50% (p <0.05). In the regions of low shear flow, ioxaglate (0.3 ml/min) also reduced platelet deposition significantly (by 52% vs. control results; p <0.05). Thus the three agents evaluated--ioxaglate, iohexol, and iodixanol--all produced anticoagulant and antiplatelet effects and were inherently antithrombotic in vivo. The most striking effects were seen with the low osmolarity, ionic contrast agent ioxaglate.  相似文献   
107.
Second primary neoplasms in patients with laryngeal carcinoma   总被引:5,自引:0,他引:5  
OBJECTIVES: To better define the characteristics of second primary malignancies appearing in patients suffering from head and neck cancers, and more specifically laryngeal carcinoma, and to elicit those parameters that may be of assistance in better diagnosing, treating, and predicting outcome in such patients. STUDY DESIGN: Retrospective review of a group of 514 compliant subjects, examined and treated during an 8-year period until 1996. After initial diagnosis and subsequent treatment, rigorous follow-up ensured systematic screening of the subjects, who underwent standard examinations in outpatient clinics for periods of up to 56 months. RESULTS: Of 514 cases followed, presence of second primary neoplasms was established in 42 or 8.17%, 8 being synchronous and 34 metachronous of the original primary lesion. CONCLUSIONS: Respiratory and upper gastrointestinal localizations were primarily affected, incidence was highest in septuagenarians, and staging of the primary was found to be irrelevant to the incidence rates of second primaries. No statistical significance was attached to the fact that supraglottic primary tumors showed slightly higher second primary rates; the same applying for well-differentiated primary tumors compared with poorly differentiated ones. Modality of treatment surgery, and radiotherapy being the options in question-did not in the long run statistically influence incidence rates. Throughout, reference to current literature and this study's relevance in light of similar efforts were taken into account.  相似文献   
108.
输血和大多数临床治疗技术一样,存在着一定的风险,输血风险主要由免疫性输血风险和输血感染性风险两大类相关的安全问题。20世纪80年代开始,由于艾滋病的发现迫使输血相关的安全问题更进一步成为公众关注的焦点。随着输血用血医学的不断发展,在已经获得很好治疗效果的同时,如何更加科学的安全用血是挑战当今公共卫生事业发展的一项大课题。  相似文献   
109.
Background--Currently, the reporting and archiving of echocardiographic data suffer from the difficulty of representing heart motion on printable 2-dimensional (2D) media. Methods and Results--We studied the capability of holography to integrate motion into 2D echocardiographic prints. Images of normal human hearts and of a variety of mitral valve function abnormalities (mitral valve prolapse, systolic anterior motion of the mitral leaflets, and obstruction of the mitral valve by a myxoma) were acquired digitally on standard echocardiographic machines. Images were processed into a data format suitable for holographic printing. Angularly multiplexed holograms were then printed on a prototype holographic "laser" printer, with integration of time in vertical parallax, so that heart motion became visible when the hologram was tilted up and down. The resulting holograms displayed the anatomy with the same resolution as the original acquisition and allowed detailed study of valve motion with side-by-side comparison of normal and abnormal findings. Comparison of standard echocardiographic measurements in original echo frames and corresponding hologram views showed an excellent correlation of both methods (P<0.0001, r2=0.979, mean bias=2.76 mm). In this feasibility study, both 2D and 3D holographic images were produced. The equipment needed to view these holograms consists of only a simple point-light source. Conclusions--Holographic representation of myocardial and valve motion from echocardiographic data is feasible and allows the printing on a 2D medium of the complete heart cycle. Combined with the recent development of online holographic printing, this novel technique has the potential to improve reporting, visualization, and archiving of echocardiographic imaging.  相似文献   
110.
The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis.  相似文献   
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