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41.
Kaplan C  Diril N  Sahin S  Cehreli MC 《Biomaterials》2004,25(18):4019-4027
The potential mutagenicity of a zinc phosphate (Poscal), a polycarboxylate (Aqualox) and glass ionomer cements with (Argion) and without (Meron) silver reinforcement were characterized by employing the Ames Salmonella/microsome test. The materials were eluted in dimethyl sulphoxide or physiologic saline and the aliquots were used either immediately or after an incubation period of 24h at 37 degrees C. Mutagenic effects of the materials were tested on Salmonella typhimurium strains TA 98, TA 100, TA 102 and TA 1535 using the standard plate incorporation assay, and in the presence or absence of S9 fraction from rat liver. Poscal and Aqualox elicited mutagenic effects on S. typhimurium TA 98 and TA 1535, whereas Meron exhibited mutagenic effects on S. typhimurium TA 98. No mutagenic effects were detected for Argion. The type of solvent, dose of the material and incubation as well as the interactions between these factors exhibited varying degrees of influences on the mutagenic activities of the cements (P<0.05 and P<0.1). We conclude that zinc phosphate, polycarboxylate, and glass ionomer cements may have possible mutagenic activities.  相似文献   
42.
Journal of Public Health - Because an increasing number of patients travel internationally to seek medical care, Turkey offers comprehensive and outstanding services under extraordinary conditions...  相似文献   
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44.
Pain during sexual activity and ejaculation are the unspoken long-term complications of groin hernia repair. Laparoscopic surgical techniques are associated with decreased post-operative pain and earlier return to daily activities, but its effect on these complications is unclear. This study aims to investigate the effect of transabdominal preperitoneal repair (TAPP) on de-novo pain during sexual intercourse and ejaculation and to compare with open repair. For this reason, two groups were determined according to the surgical technique: the Lichtenstein repair and the TAPP groups and a questionnaire was sent to the patients a minimum of 6 months following the surgery. A total of 317 patients included, as 115 in TAPP and 202 in Lichtenstein repair group. No significant difference was observed concerning pre-operative pain during sexual activity and ejaculation in both groups (p = .75, p = .56). Following the surgery, the number of patients experiencing painful sexual activity was significantly higher in the Lichtenstein repair group compared to the TAPP group (19.3% vs. 11.3%, respectively, p = .03). The post-operative painful ejaculation rate was also significantly lower for the TAPP group (p = .04). The lower rates of post-operative dysejaculation and pain during sexual activity can be achieved with the advantage of laparoscopic surgery.  相似文献   
45.
Background:To evaluate the changes in penile sensation by electrophysiological tests in patients who underwent radical prostatectomy (RP) and to demonstrate the role of dorsal penile nerve injury in postoperative erectile dysfunction.Materials and methods:Twenty-six volunteer patients who were eligible for RP were included in the study. Preoperative penile sensory electromyography and the International Index of Erectile Function-5 (IIEF-5) questionnaire were done for each patient. Erectile function assessment and electrophysiological evaluation of penile sensation were repeated at postoperative 3rd and 6th months.Results:Postoperative IIEF-5 scores and electromyography values were significantly lower than preoperative findings (p < 0.05). The IIEF-5 scores in the nerve sparing-RP (NS-RP) group were significantly higher than the non-nerve sparing-RP (NNS-RP) group in the postoperative period. Nerve conduction velocity values in the NS-RP group were also higher than the NNS-RP group at the postoperative 3rd and 6th months. However, these changes were not statistically significant (p > 0.05).Conclusions:Patients who underwent RP have decreased penile sensation due to cavernous nerve damage and a possible dorsal penile nerve injury. The decrease of penile sensation may be associated with postoperative erectile dysfunction.  相似文献   
46.
We measured vitreous and serum levels of pefloxacin after oral administration. Twenty patients with retinal detachments undergoing vitrectomy were recruited into this study. Each patient received 400 mg pefloxacin orally 1 to 12 hours before vitrectomy. Vitreous fluid (0.1 mL) was aspirated at surgery. Vitreous levels of pefloxacin were determined by high-performance liquid chromatography. Six hours after oral administration, an average level of 1.37 g/mL of pefloxacin was measured in the vitreous samples. These levels were well above the minimum inhibitory concentration (MIC) for most organisms termed sensitive to pefloxacin. Oral administration of pefloxacin may play an important role in the prevention or management of endophthalmitis.Supported in part by U.S. Public Health Service grants EY07541 and EY02377 from the National Eye Institute, National Institutes of Health, Bethesda, MD, USA.  相似文献   
47.
Orbital ossifying fibroma is an extremely rare condition, especially in adults. This rare tumor mostly develops at the medial wall of the orbit. We report a histopathologically confirmed ossifying fibroma involving the lateral orbital wall in an adult. This case suggests that orbital ossifying fibroma should be considered in the differential diagnosis of orbital bony lesions in adults and that unusual presentations may occur.  相似文献   
48.
The aim of the present study was to examine subpreputial bacteriology and to compare it with the urine cultures of healthy male children. Seventy-two male children were divided into two groups as A and B according to age. In both groups preputial sac and urine cultures were taken simultaneously. Gram (+) enteric cocci were the most common isolated pathogens from the preputial sac in group B. Enterobacter, E. coli and staphylococci species were isolated from the urine cultures of three patients in group B. We could not find any difference between the preputial sac swabs of group A and B patients, but the isolation rate of urine cultures of group A patients was significantly higher than group B (p < 0.05). The findings of the present study support a potential role of the prepuce acting as a reservoir of faecal bacteria in the pathogenesis of UTI in male infants, especially in the first year of life. Improved penile hygiene after the first year of life does not alter the subpreputial bacteriology, but significantly decreases the contamination of urine. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
49.
The aim of the present study is to evaluate whether paroxetine (a selective serotonin re-uptake inhibitor) can modify the contractile responses of isolated vas deferens. Some contractile agents, potassium chloride (KCl), adenosine 5'-triphosphate (ATP), noradrenaline (NA), and electrical field stimulation (EFS) caused contractions both in epididymal and prostatic portions of vas deferens. Paroxetine (PX) in concentrations 10(-7) and 10(-6)M potentiated the contractions to KCl and ATP only in epididymal portion but in higher concentrations (10(-5) and 10(-4)M) inhibited the responses in both portions. NA responses were inhibited by PX in all concentrations used, both in prostatic and epididymal portions. Prazosin (PR), an alpha adrenergic receptor blocking agent, inhibited PX-induced potentiation observed for higher concentrations of KCl. PR also inhibited PX-induced potentiation on the responses to ATP in epididymal portion. Pretreatment with PX (10(-7) to 10(-6)M) increased the contractions to EFS but in 10(-5) and 10(-4)M concentrations inhibited them. Even though the preparations were washed out, the inhibited responses of contractile agents could not be restored. After a washout period for PX, when Bay K 8644 (calcium channel activator) was added to the bath medium, the contractile responses to KCl were partially restored. In calcium-free medium, KCl caused contractions in concentrations higher than 80 mM with lower amplitudes which were not affected by PX. Reserpinization did not change the inhibitory pattern of PX's effect on exogenously applied NA in all concentrations tested. In reserpinized rats, the potentiation caused by PX in exogenously applied ATP responses was not observed. In conclusion, we can say that PX has two different effects: inhibition and potentiation of contractions to various agonists. The inhibitory effect of the drug can be explained by a calcium channel blocking activity. The potentiating effect of the drug is mainly related to its presynaptic action, such as NA re-uptake inhibitory effect.  相似文献   
50.
Perioperative spasm of internal mammary artery is a common experience in coronary artery bypass grafting. Many techniques were described of harvesting the internal mammary artery to prevent vasospasm. We investigated the comparison of the contracting and relaxing responses of human internal mammary artery grafts harvested by two different methods. Patients were divided into two groups depending on the harvesting technique. In the first and second groups arteries were harvested by classical and carbon dioxide insufflation techniques, respectively. In both groups, endothelial function of arteries was assessed by precontracting the rings with phenylephrine (10(-5)M) and dilatating them by cumulative acetylcholine (10(-8) to 10(-5)M) concentrations. Cumulative concentration-response curves for phenylephrine (10(-8) to 10(-4)M), noradrenaline (10(-9) to 10(-4)M), and 5-hydroxytryptamine (10(-9) to 10(-4)M) were obtained in all groups. Endothelial integrity of arteries were histopathologically evaluated. In both groups, acetylcholine caused concentration-dependent relaxations in rings precontracted with phenylephrine (10(-5)M). In arteries harvested by carbon dioxide insufflation technique, acetylcholine caused significantly higher relaxations compared to the rings obtained by classical technique (p<0.05). In all rings of study groups, phenylephrine, noradrenaline and 5-hydroxytryptamine caused concentration-dependent contractions. There was not any significant difference in concentration-dependent responses of these contracting pharmacological agents between the groups. Histopathological evaluation revealed no major arterial damage in both groups. Carbon dioxide insufflation technique does seem not only to protect the integrity of the endothelium and the whole vessel, but also prevent the possible vasospasm of the internal mammary artery segments.  相似文献   
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