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The complexation of cyclo(Pro17O-Gly15N) and cyclo(Gly17O-Pro) with CO2+ ions has been studied by 17O, 14N and 15N n.m.r. spectroscopy in aqueous solution. 17O, 14 N and 15N transverse relaxation times and chemical shifts were measured as a function of temperature. The 17O n.m.r. studies unequivocally demonstrate that the cobaltous ion binds to the peptide oxygen of both compounds. The hyperfine coupling constant and the peptide residence times were found to be A =–0.165 MHz and – 0.145 MHz, μ= 16, and 92μsec for cyclo(Pro17O-Gly15N) and cyclo(Gly17O-Pro), respectively. The 14N and 15N studies of labeled cyclo(Pro17O-Gly15N) do not indicate binding at either the Gly15N or the Pro14N site.  相似文献   
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Introduction: Contrast‐induced acute kidney injury (CI‐AKI) is one of the leading causes of hospital‐acquired acute kidney injury. Multiple clinical studies have proposed several preventive strategies. Aims: To examine the efficacy of sodium bicarbonate compared with sodium chloride and oral N‐acetylcysteine (NAC) for preventive hydration after cardiac catheterization. Methods: We conducted a prospective, single‐center trial. Patients with chronic kidney disease (CKD) stage III–IV undergoing cardiac catheterization were allocated to receive either an infusion of 0.9% sodium chloride and oral NAC or 154 mEq/L sodium bicarbonate. Main: Outcome measure CI‐AKI, defined as an increase of 25% or 0.3 mg/dL or more in plasma creatinine within 2 days of contrast administration. Results: Ninety‐three patients were allocated to one of the two groups: 42 patients in the saline plus NAC group and 51 patients in the bicarbonate group. There were no statistically significant differences between the groups in the most important clinical and procedural characteristics. Baseline plasma creatinine levels, estimated glomerular filtration rate, incidence of diabetes mellitus, hypertension, congestive heart failure, and contrast medium volume were similar. Mean plasma creatinine concentration was 1.76 ± 0.54 mg/dL in the saline and NAC group and 1.9 ± 1 mg/dL in the bicarbonate group (P = 0.23). The rate of CI‐AKI was 9.8% in the bicarbonate group and 8.4% in the saline plus NAC group. No patient required renal replacement therapy. Conclusion: Hydration with sodium bicarbonate is not more effective than hydration with sodium chloride and oral NAC for prophylaxis of CI‐AKI in patients with CKD stage III–IV undergoing cardiac catheterization.  相似文献   
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Human papillomavirus (HPV) is the most frequent sexually transmitted viral infection. It is necessary to know HPV genotype distribution to identify how many women will be protected by HPV vaccines. During a period of 18 months, we have analyzed 2362 HPV positive reporting data from a secondary demand screening program in three regions in Spain (Cantabria, Leon and Burgos). The study has been conducted using polymerase chain reaction and tube array hybridization covering the 35 HPV genotypes described as affecting anogenital mucosa. There were no significant differences between the three regions according to genotype distribution. The most frequent were HPV16 (19.18%), HPV53 (11.26%) and HPV58 (7.66%). HPV18 was the source of 4.02% of infections. High‐risk HPVs were found in 1863/2362 cases. HPV16 was present in 24.3% of high‐risk infections and HPV18 was found in 5.1%. Uncommon genotypes (<5% of the total prevalence each) were found in 17,9% of the total high‐risk infections (334/1863). Multiple infections were diagnosed in 22% of the cases. The HPV genotype distribution is different from previously published data when multiple types are included in the screening. Both HPV16/18 account for 30% of high‐risk infections in a clinical setting in Spain. The presence of multiple genotypes is very common among the population.  相似文献   
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Abstract: Purpose : Prescribed, patient-applied tooth lightening agents, or nightguard vital bleaching, typically utilizes a 10% carbamide peroxide agent applied during nocturnal hours. The purpose of this randomized double-blind study was to compare the amount of tooth color change in two groups of subjects using dentist-supervised, patient-applied 10% carbamide peroxide gel.
Materials and Methods : One group used Opalescence® (Ultradent Products Inc., South Jordan, Utah) and the other Nite White Excel® (Discus Dental, Inc., Los Angeles, California). Evaluation of tooth color for the six maxillary anterior teeth was done using a Vita shade guide at baseline, 1, 2, and 4 weeks. Subjects were instructed to apply the gel nocturnally using a custom-made soft tray 8 hours per day for 2 weeks. The 16 tabs of the shade guide were ranked according to value from darkest to lightest. The number (1–16) that correlated to the shade tab selected as the match for each tooth was the outcome variable. A Kruskal-Wallis one way analysis of variance on ranks was used.
Results : The test revealed no statistically significant difference between Opalescence® and NiteWhite® Excel for lightening the teeth ( p = .807). The color change was still significant after 2 weeks without further bleaching activity. The baseline evaluation of the maxillary incisors and canines for all subjects, regardless of group, demonstrated a significant shade difference, with the canines being darker. This difference was not seen after 2 weeks of active bleaching or at the 4-week evaluation.  相似文献   
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Synthetic or biological materials can be used for the surgical repair of pelvic organ prolapse (POP) or stress urinary incontinence (SUI). While non‐degradable synthetic mesh has a low failure rate, it is prone to complications such as infection and erosion, particularly in the urological/gynecological setting when subject to chronic influences of gravity and intermittent, repetitive strain. Biological materials have lower complication rates, although allografts and xenografts have a high risk of failure and the theoretical risk of infection. Autografts are used successfully for the treatment of SUI and are not associated with erosion; however, can lead to morbidity at the donor site. Tissue engineering has thus become the focus of interest in recent years as researchers seek an ideal tissue remodeling material for urogynecological repair. Herein, we review the directions of current and future research in this exciting field. Electrospun poly‐L‐lactic acid (PLA) and porcine small intestine submucosa (SIS) are two promising scaffold material candidates. Adipose‐derived stem cells (ADSCs) appear to be a suitable cell type for scaffold seeding, and cells grown on scaffolds when subjected to repetitive biaxial strain show more appropriate biomechanical properties for clinical implantation. After implantation, an appropriate level of acute inflammation is important to precipitate moderate fibrosis and encourage tissue strength. New research directions include the use of bioactive materials containing compounds that may help facilitate integration of the new tissue. More research with longer follow‐up is needed to ascertain the most successful and safe methods and materials for pelvic organ repair and SUI treatment.  相似文献   
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