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Herein, a novel poly(2-mercaptobenzothiazole) coated magnetic nanoadsorbent derived from zeolitic-imidazole framework-8 (ZIF-8) was synthesized and then employed for the extraction/preconcentration of trace amounts of palladium and silver in various real matrixes. In this way, magnetite was fabricated first, and then functionalized with tetraethyl orthosilicate. After that, the synthesized magnetite@silica was coated with the ZIF-8 to obtain magnetic ZIF-8. Afterward, the magnetic ZIF-8 was pyrolyzed under the protection of a nitrogen atmosphere to get a magnetic carbon nanoadsorbent. Finally, the magnetic carbon was functionalized with a conductive polymer (poly-2-mercaptobenzothiazole). Fabrication of the nanoadsorbent was affirmed with scanning and transmission electron microscopies, elemental analysis, X-ray diffraction, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. The method is linear from 0.25 to 200 μg L−1 for silver, and from 0.5 to 250 μg L−1 for palladium. The detection limits are 0.07 and 0.15 μg L−1 for Ag and Pd, respectively. The precision was evaluated at three concentration levels (1, 75, 200 μg L−1, n = 5) and all the relative standard deviation (RSD) values were lower than 10.3%. In the end, the new method was utilized for the preconcentration/determination of trace amounts of palladium and silver in various real matrixes, satisfactorily (relative recovery: 86% to 104%; RSD%: 4.0–9.5%).

A novel poly(2-mercaptobenzothiazole) coated magnetic nanoadsorbent derived from zeolitic-imidazole framework-8 was synthesized and then employed for the extraction/preconcentration of trace amounts of palladium and silver in various real matrixes.  相似文献   
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The objective of this analysis was to compare the performance characteristics of two human papillomavirus (HPV) DNA detections assays, the Hybrid Capture 2 assay (HC2) and the SPF(10) assay, for the detection of carcinogenic HPV. Data are from the enrollment visits of women who participated in the randomized, double-blind, placebo-controlled phase III HPV16/18 Vaccine Trial in Guanacaste, Costa Rica. We compared the results of HC2 and SPF(10) testing of cervical specimens. Since the line probe assay (LiPA) detection system does not distinguish between HPV type 68 (HPV68; which is targeted by HC2) and HPV73 (which is not targeted by HC2), for SPF(10)-LiPA, we defined the carcinogenic HPV types as the 12 HC2-targeted types (types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 59), HPV68/73, and the HC2-cross-reactive, carcinogenic type HPV66. The kappa values and the performance characteristics for the detection of cervical abnormalities were ascertained. Paired observations were available for 5,683 sexually active, young women (median age, 21 years). The prevalence of carcinogenic HPV types was 35% (n=1,962) by HC2 and 35% (n=2,003) by SPF(10)-LiPA. There were no differences in the prevalence of carcinogenic HPV types by HC2 and SPF(10)-LiPA among women with normal, atypical squamous cells of undetermined significance and high-grade squamous intraepithelial lesion cytology. Among women with low-grade squamous intraepithelial lesion cytology, HC2 was more likely to test positive than SPF(10)-LiPA for the carcinogenic HPV types (87% and 79%, respectively; P=0.001) as a result of HC2 cross-reactivity with HPV types 40, 43, 44, 53, 54, 60, 70, and 74. The crude agreement between the two assays was 88%, with a kappa value of 0.75 (95% confidence limits, 0.73 to 0.76). We observed very good agreement between HC2 and SPF(10)-LiPA for carcinogenic HPV type detection.  相似文献   
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Background

Investigations of vaccine efficacy and immunogenicity for adult females receiving fewer than three doses of human papillomavirus (HPV) vaccine have suggested protection against infection and precancerous lesions. We investigated the immunogenicity of bivalent HPV vaccines among adolescent girls from Uganda who received one, two, or three vaccine doses.

Methods

Young girls vaccinated through a government program in Uganda were invited to participate. HPV16- and HPV18-specific antibodies were measured at ≥24 months after the last vaccine dose using an enzyme linked immunoassay in girls who received one (n = 36), two (n = 145), or three (n = 195) doses.

Results

Nearly all subjects (99%) were HPV16 and HPV18 seropositive at the time of blood-draw. Geometric mean antibody levels (GMTs) were: HPV161-dose = 230 EU/mL, HPV162-dose = 808 EU/mL, and HPV163-dose = 1607 EU/mL; HPV181-dose = 87 EU/mL, HPV182-dose = 270 EU/mL, and HPV183-dose = 296 EU/mL. The GMT ratio for 2:3 doses was 0.50 (HPV16) and 0.68 (HPV18) and did not meet the non-inferiority criteria (i.e., lower bound of 97.5% confidence interval of the GMT ratio greater than 0.50). The GMT ratio for 1:3 doses for HPV16 and HPV18 was inferior, but absolute GMTs for one dose were higher than adult women who received one dose (HPV16 = 124 EU/mL, HPV18 = 69 EU/mL) where efficacy has been demonstrated.

Conclusions

Even though immunogenicity with less than three doses did not meet a priori non-inferiority thresholds, antibody levels measured ≥24 months after last dose were similar to those of adult women who have been followed for more than eight years for efficacy.  相似文献   
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Tinnitus can cause extreme morbidity. Despite many attempts to find a treatment for idiopathic cases, they remain difficult to manage. Because nerve injury is one of the suspected etiologies of tinnitus and because gabapentin has been found to be effective in treating nerve injuries, some authors have attempted to determine if gabapentin has a role in treating tinnitus. Although gabapentin was found to be ineffective for tinnitus in these previous studies, to the best of our knowledge no studies have been performed that took into consideration the presence of various accompanying factors and concomitant diseases that might influence its effect. We conducted a prospective, randomized, double-blind, placebo-controlled clinical trial of gabapentin for idiopathic tinnitus. We treated 40 patients with gabapentin and measured its effectiveness by comparing differences between pre- and post-treatment Tinnitus Severity Index (TSI) values and tinnitus loudness scores. We also compared these outcomes with those of a group of 40 matched placebo controls. At study's end, we found no significant differences between the gabapentin and control groups in mean decreases in TSI value and loudness score (p=0.85 and p=0.12, respectively). However, we did find that patients with hypertension, diabetes, and/or dyslipidemia showed a better response to gabapentin than did those with tinnitus alone (p=0.01). We conclude that although there was no statistically significant difference between gabapentin and placebo in treating isolated tinnitus or tinnitus overall, patients with concomitant hypertension, diabetes, and/or dyslipidemia may benefit from gabapentin.  相似文献   
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Antioxidant and antihemolytic activities of acetone extracts of Hyssopus angustifolius flowers, leaf and stems were investigated employing different in vitro and ex vivo assay systems. IC50, for 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical-scavenging activity were 239.4 +/- 8.4 microg/mL for flowers, 357.8 +/- 11.1 microg/mL for stems and 182.5 +/- 7.5 microg/mL for leaf. All extracts showed moderate nitric oxide scavenging activity. The leaf extract exhibited better hydrogen peroxide scavenging and Fe2+ chelating activity than the others (IC50 were 261.0 +/- 6.2 microg/mL for hydrogen peroxide and 534.0 +/- 9.9 microg/mL for Fe3+ chelating activity). The extracts exhibited good antioxidant activity in linoleic acid peroxidation system and weak reducing power ability. The leaf extract showed better antihemolytic activity than the flower and stem (IC50 = 65.7 +/- 1.8 microg/mL).  相似文献   
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Background: In Iran, breast cancer is the second most common malignancy among women and diagnosed in advanced stages almost a decade earlier than women living in western countries. Objective: To determine the level of knowledge and attitudes toward breast self-examination (BSE) among Iranian women. Methods: In a cross-sectional multi-center study, 3,060 women aged between 25 and 54 years attending between July and October 2009 to 11 general health care centers located in 11 cities of Iran, were interviewed to assess their knowledge and attitudes toward BSE. Results: Of the total, the data of 3030 were found eligible for analyses. The median (interquartile range [IQR]) age of participants was 40 (14) years; 2687 (88.7%) were married; 1496 (49.4%) women performed BSE, 290 of whom (19.4% of performers and 9.6% of all studied women) did it using a correct method and at an appropriate time. More than three-quarters of performers (n=1141) learned about BSE from a health care provider; 248 (16.6%, 95% confidence interval [CI]: 14.7% to 18.5%) had abnormal findings, 11 (0.7% , 95% CI: 0.3% to 1.2%) of which were malignant. Of 1534 (50.6%) non-performers, 474 (30.9%) did not know how to do BSE; the remaining women did not do BSE for fear of being found positive for cancer or did not care about it. Being a health care provider, married, educated, and knowing of a person with breast cancer was associated with performing BSE. Conclusions: The level of BSE practice and knowledge among Iranian women is unsatisfactory. We should emphasize appropriate education of women.  相似文献   
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