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11.
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   
12.
The objective of this study was to test the hypothesis that composite restorative materials possess an elastic-brittle nature and therefore will exhibit a size effect for flexure strength data. The experimental material consisted of 20 wt% 60:40 BISGMA:TEGDMA, 10 wt% colloidal silica, and 70 wt% Sr glass and was cured by light irradiation. Two sizes of flexure specimens were fabricated: 3.2x1.6x35 mm, and 6.25x3.1x35 mm. Half of the specimens made were soaked to equilibrium weight gain in 50:50 ethanol:water. The fracture strengths were measured in four-point bending tests. The beams under load were modelled by the finite element package ABAQUS. A statistical fracture mechanics methodology embodied in a public domain computer program called CARES/LIFE, developed by NASA, utilized the ABAQUS input and the fracture strengths of the smaller specimens to predict the fracture strengths of the larger specimens. In making the computation it used an approach that combines a Weibull distribution of flaw size with Batdorf's fracture mechanical model for failure at a material flaw. Both the soaked and unsoaked specimens exhibited Weibull behaviour, with shape parameters ranging from 4.04 to 8.15. Soaking had a clearly detrimental effect on the strengths of specimens of both sizes, and produced a comparable percentage reduction in the estimated scale parameter of the fracture strength distribution. Both the soaked and unsoaked specimens also exhibited a clear and comparable size effect, i.e. the larger specimens had a fracture strength that was lower than that of the smaller specimens by roughly the same percentage. Moreover, the magnitude of the size effect was well predicted by the CARES/LIFE methodology for both the soaked and the dry specimens. The elastic-brittle character of both soaked and unsoaked composite specimens was validated by load-deflection data, the magnitude of the Weibull shape parameters of the observed fracture strength data (<10), and the observed effect of specimen size. The accuracy of CARES/LIFE in predicting the magnitude of the observed size effect in beams of two different sizes strongly suggests that CARES/LIFE will be useful for computation of failure probabilities for clinically relevant structures.  相似文献   
13.
The double-staple technique in colorectal anastomoses: a critical review.   总被引:3,自引:0,他引:3  
The widespread availability and use of stapling devices have changed colorectal surgery. In 1980, Knight and Griffen developed the "double-staple" technique, using a circular stapler to transect a linear rectal staple line. This eliminated the need for a hand-sewn, distal purse string, which was sometimes difficult or even impossible to accurately place low in the pelvis. To evaluate this procedure, the authors have reviewed their results with the double-staple technique over the past 5 years. One hundred four patients underwent this procedure between 1985 and 1990 at Thomas Jefferson University Hospital (Philadelphia, PA). There were 60 men and 44 women, with a mean age of 62.4 years. Seventy-two patients underwent operation for carcinoma of the rectum or sigmoid. Thirty-five of these had preoperative radiation therapy. Other diagnoses included 1) diverticular disease, 2) rectal prolapse, 3) villous adenoma, 4) endometrial carcinoma, 5) fistula, 6) stricture, 7) Crohn's disease, 8) colonic endometriosis, 9) lymphoma, 10) ovarian carcinoma, and 11) ulcerative colitis. Incomplete "donuts" were observed in 5 patients. Diverting colostomies were performed in 23 patients, ileostomies in 3. Postoperative complications relating to the double-staple technique itself included a rectovaginal fistula in 1 patient. There were 3 clinical leaks (2.8%), all treated nonoperatively. No strictures were observed. As previously observed, the authors believe the double-staple technique offers certain advantages over traditional, hand-sewn and stapled anastomoses, for instance: 1) there is significantly less contamination, 2) the anastomosis is technically easier, and 3) bowel segments of different diameters can be easily anastomosed.  相似文献   
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15.
The central action of the potential antidepressant drug pizotifen (Sandomigran) was studied in mice, rats and rabbits. Pizotifen in doses up to 10 mg/kg i.p. was ineffective in classic tests for antidepressant activity. It neither antagonized the effects of reserpine in rats (hypothermia, ptosis) nor potentiated the effects of amphetamine (in mice and rats), nialamide or L-dopa (in mice) on locomotor activity. However, its antidepressant activity was found in the despair test in rats.On the other hand, pizotifen inhibited the head twitch reaction induced by L-5-hydroxytryptophan in mice (ED50=0.009 mg/kg, i.p.) and by 5-methoxytryptamine (+tranylcypromine) in rats (ED50=0.45 mg/kg, i.p.). It also antagonized tryptamine-induced clonic convulsions of fore-paws in rats (ED50=0.35 mg/kg, i.p.), and in doses of 5–10 mg/kg s.c. inhibited hyperthermia produced by LSD in rabbits. Finally, pizotifen (0.1–0.3 mg/kg, i.v.) inhibited or abolished LSD- or quipazine-induced stimulation of the hind limb flexor reflex of spinal rats; the above effect was not due to noradrenolytic action of the drug. These results suggest that pizotifen strongly blocks the central postsynaptic serotonin receptors.  相似文献   
16.
Objective: This study aimed to analyze risk factors for amputation (overall, minor and major) in patients with diabetic foot ulcers (DFUs).Methods: 407 patients with DFUs (286 male, 121 female; mean age = 60, age range = 32-92) who were managed in a tertiary care centre from 2009 to 2019 were retrospectively identified and included in the study. DFUs were categorized based on the Meggit-Wagner, PEDIS, S(AD)SAD, and University of Texas (UT) classification systems. To identify amputation risk-related factors, results of patients with DFUs who underwent amputations (minor or major) were compared to those who received other adjunctive treatments using Chi-Square, one-way analysis of variance (ANOVA) and Spearman correlation analysis.Results: The mean C-reactive protein (CRP) and White Blood Cell (WBC) values were significantly higher in patients with major or minor amputation than in those without amputation. The mean Neutrophil (PNL), Platelets (PLT), wound width, creatinine and sedimentation (ESR) values were significantly higher in patients with major amputation compared to other groups of patients. Elevated levels of High-density lipoprotein (HDL), Hemoglobin (HGB) and albumin were determined to be protective factors against the risk of amputation. Spearman correlation analysis revealed a positive-sided, strong-levelled, significant relation between Wagner grades and amputation status of patients.Conclusion: This study has identified specific factors for major and minor amputation risk of patients with DFUs. Especially infection markers such as CRP, WBC, ESR and PNL were higher in the amputation group. Most importantly, Meggit Wagner, one of the four different classification systems used in the DFUs, was determined to be highly associated with patients’ amputation risk.Level of Evidence: Level IV, Prognostic Study  相似文献   
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18.
PURPOSEThis study evaluated single-center results of endovascular treatment in renal angiomyolipoma (AML) to determine whether there is clinical relevance of adding proximal coil embolization to distal particle embolization in terms of safety, efficacy, and retreatment rates.METHODSA retrospective analysis was performed to evaluate patients undergoing transarterial embolization for renal AMLs from January 2007 to October 2020. Parameters regarding patient and tumor characteristics, embolization technique, treatment outcome, and complications were recorded. Patients were divided into 2 groups as A (only particle group) and B (particle + coil group) based on the type of embolic agent used for treatment. Comparative analysis was performed between the 2 groups in terms of tumor size reduction, retreatment, and complication rates. RESULTSIn this study, 42 patients (37 (88.1%) females and 5 (11.9%) males) harboring 48 AMLs were included. The mean age was 43.46 (range, 20-78). The technical success rate was 95.8% (46 of 48 procedures). The mean size reduction was 1.94 ± 1 cm (P  < .001) after treatments; however, no significant difference was seen between groups in terms of tumor size reduction. Retreatment rates were 3.1% (1 of 32 cases) in group A and 14.3% (2 of 14 cases) in group B (P  = .21). No significant difference was found between groups in terms of bleeding and complication rates during the perioperative period. Mean follow-up duration was 26.48 ± 25.71 (range, 2-102) months.CONCLUSIONIn this study, no clear supplementary benefit was observed in terms of safety and efficacy with the adjunction of coils to distal particle embolization in the management of AMLs.

Main points
  • Transarterial embolization is safe and effective in reducing lesion size and bleeding rates in the management of angiomyolipomas.
  • Lesion size reduction can be achieved with both techniques; solely microparticle embolization or distal microparticle embolization plus proximal coil embolization.
  • Proximal coil embolization does not provide an additional benefit with lesions having intratumoral microaneurysms ≥5 mm as the study showed no difference in complication and bleeding rates.
Renal angiomyolipoma (AML) is one of the most common benign tumors of the kidney, with an incidence of 0.4% in the general population.1,2 AMLs are seen in 2 forms; sporadic and tuberosclerosis (TSC) related. Sporadic form accounts for 80% of the AML cases. TSC-related AMLs tend to be bilateral, multifocal, larger with a faster growth rate and are more symptomatic than the sporadic type.3 AMLs have slow growth rates and rarely necessitate invasive treatment at all times.4 Historical data suggest that AMLs equal to or larger than 4 cm and those that have 5 mm or larger microaneurysms tend to be more symptomatic and prone to hemorrhage.5,6 Although a treatment indication based on tumor size larger than 4 cm is subject to dispute,7 treatment decisions are often made using these cut-off values in the literature. Treatment options consist of medical treatment, surgery, transarterial embolization (TAE), and thermal ablation with no definitive recommendation on the first-line treatment choice.8,9 However, because of its less-invasive nature, TAE is a favored choice in the management of AMLs over surgery. So far, various embolic agents (ethanol, microparticles, coils, gel foam, etc.) have been used in the management of patients with AML.10 Concerning the embolic materials, Patatas et al.11 compared solely coil embolization with solely microparticle embolization in transarterial embolization of AMLs. They found similar reduction rates on computed tomography (CT) follow-up between the 2 groups. Ewalt et al.12 showed that microparticle plus coil embolization is effective in terms of size reduction in large (>4 cm) and symptomatic and TSC-related AMLs. Although based on the literature, coils, microparticles, and microparticle + coil embolization are all safe and efficient, there are no clear data on the additional benefit of adding coil embolization to microparticle embolization in terms of treatment efficacy. Therefore, this study aimed to evaluate within single-center results whether there is clinical relevance of adding proximal coil embolization to distal microparticle embolization in terms of safety, efficacy, and retreatment rates.  相似文献   
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20.
Background Numerous studies have demonstrated increased cardiovascular risk in psoriasis. Circulating endothelial cells (CECs) have been proposed as a new marker of endothelial dysfunction that plays an important role in pathogenesis of atherosclerosis. Objective The aim of this study was to compare the number of CECs in psoriatic patients to a control group and to analyze possible correlations between the numbers of CECs and the plasma levels of classical markers of endothelial dysfunction, such as: sICAM‐1, sE‐selectin and von Willebrand factor (vWF). Methods The number of CECs, identified as CD146 + / CD45‐ cells, were determined in peripheral blood with using flow cytometry in psoriatic patients (n = 63) and controls (n = 31). The plasma levels of: sICAM‐1, sE‐selectin, vWF were measured with ELISA. The severity of psoriasis was assessed with PASI. Results The number of CECs was significantly increased in psoriatic patients compared with controls (P < 0.00001) and positively correlated with disease severity (R = 0.360; P = 0.0037). The levels of sICAM‐1, sE‐selectin and vWF were significantly elevated in psoriatic patients (P < 0.00001; P < 0.00001; P = 0.00072, respectively). The number of CECs was significantly, positively correlated with the levels of sICAM‐1 (R = 0.393; P = 0.0014) and vWF (R = 0.314; P = 0.012) in psoriatic patients. The levels of sICAM‐1 and sE‐selectin were positively correlated with disease severity (R = 0.356; P = 0.0041 and R = 0.407; P = 0.0009, respectively). Conclusion The increased number of CECs that correlates with disease severity and plasma levels of sICAM‐1 and vWF may indicate endothelial dysfunction or injury in patients with psoriasis.  相似文献   
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