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31.
Objective: This field study aimed to assess the noise reduction of hearing protection for individual workers, demonstrate the effectiveness of training on the level of protection achieved, and measure the time required to implement hearing protector fit testing in the workplace. Design: The National Institute for Occupational Safety and Health (NIOSH) conducted field studies in Louisiana and Texas to test the performance of HPD Well-Fit. Study sample: Fit tests were performed on 126 inspectors and engineers working in the offshore oil industry. Results: Workers were fit tested with the goal of achieving a 25-dB PAR. Less than half of the workers were achieving sufficient protection from their hearing protectors prior to NIOSH intervention and training; following re-fitting and re-training, over 85% of the workers achieved sufficient protection. Typical test times were 6–12?minutes. Conclusions: Fit testing of the workers’ earplugs identified those workers who were and were not achieving the desired level of protection. Recommendations for other hearing protection solutions were made for workers who could not achieve the target PAR. The study demonstrates the need for individual hearing protector fit testing and addresses some of the barriers to implementation.  相似文献   
32.
To establish an optimal categorization of cancer deposits without lymph node structure (extranodal cancer deposits [EX]) in a prognostic staging system, we analyzed 1,027 cases in which patients underwent potentially curative surgery for advanced colorectal adenocarcinoma. EX was classified as vascular invasion-type (VAS) or non-VAS.A total of 512 foci of EX were identified in 205 patients (20.0%), with VAS and non-VAS found in 68 and 182 patients, respectively. The hazard ratio for patients with nodal involvement was 3.6 and for patients with VAS and non-VAS, 2.5 and 4.7, respectively. Based on multivariate analysis of these 3 parameters, only nodal involvement and non-VAS were significant prognosticators. By using the Akaike information criterion, N staging was capable of predicting survival outcome with the highest accuracy when both nodal involvement and non-VAS were treated together as an N factor and VAS was treated as a T factor ("new categorization"). The clinical significance of the TNM grading system for colorectal cancer would be enhanced if we treat EX as a new categorization.  相似文献   
33.
To overcome the problems associated with sheet- or film-type anti-adhesive materials, we developed a new type of anti-adhesive material, gelatin flakes. We made two types of gelatin flakes with or without thermal cross-linking, and preliminarily examined their basic properties and the anti-adhesive efficacy using a rodent adhesion model. Both types of the gelatin flakes rapidly turned into gel and tightly attached the injured surfaces, absorbing the moisture and blood, when applied onto the abraded sites of rats. In addition, these flakes could be sprayed into the desired area by compressed air through a device with a long, thin tube, which could be used in laparoscopic surgery. The anti-adhesive effects of both types of gelatin flakes were similar, and both types were significantly superior compared to the non-treated group. Although further investigations are necessary, the gelatin flakes have unique and useful properties and satisfactory anti-adhesive effects, which indicate that they may be applicable in laparoscopic surgery.  相似文献   
34.

Background

Combined treatment with cyclosporine microemulsion preconcentrate (CyA MEPC) and steroids has been widely used for idiopathic membranous nephropathy (IMN) associated with steroid-resistant nephrotic syndrome (SRNS). Recent studies have shown that once-a-day and preprandial administration of CyA MEPC is more advantageous than the conventional twice-a-day administration in achieving the target blood CyA concentration at 2 h post dose (C2). We designed a randomized trial to compare these administrations.

Methods

IMN patients with SRNS (age 16–75 years) were divided prospectively and randomly into 2 groups. In group 1 (n = 23), 2–3 mg/kg body weight (BW) CyA MEPC was given orally once a day before breakfast. In group 2 (n = 25), 1.5 mg/kg BW CyA MEPC was given twice a day before meals. CyA + prednisolone was continued for 48 weeks.

Results

Group 1 showed a significantly higher cumulative complete remission (CR) rate (p = 0.0282), but not when incomplete remission 1 (ICR1; urine protein 0.3–1.0 g/day) was added (p = 0.314). Because a C2 of 600 ng/mL was determined as the best cut-off point, groups 1 and 2 were further divided into subgroups A (C2 ≥600 ng/mL) and B (C2 <600 ng/mL). Groups 1A and 2A revealed significantly higher cumulative remission (CR + ICR1) (p = 0.0069) and CR-alone (p = 0.0028) rates. On the other hand, 3 patients with high CyA levels (C2 >900 ng/mL) in Group 1A were withdrawn from the study because of complications.

Conclusion

CyA + prednisolone treatment is effective for IMN with associated SRNS at a C2 of ≥600 ng/mL. To achieve remission, preprandial once-a-day administration of CyA at 2–3 mg/kg BW may be the most appropriate option. However, we should adjust the dosage of CyA by therapeutic drug monitoring to avoid complications.  相似文献   
35.
We investigated the cross-sectional relationship between ankle brachial index and cardiovascular disease risk factors, including C-reactive protein (CRP), among Japanese elderly, a topic which has had little prior epidemiologic study. Our study population comprised 946 subjects aged at least 70 years in whom both CRP and ankle brachial index were measured. The participants were classified into a low (ankle brachial index<0.9) and normal ankle brachial index group. We found that current smoking, high-density lipoprotein cholesterol <40 mg/dl, a low body mass index (continuous variable), hypertension, diabetes and statin use were all significantly related to a lower ankle brachial index. Higher log-transformed CRP level was significantly related to a lower ankle brachial index after adjustment for the cardiovascular risk factors mentioned above (p <0.01). The odds ratios for low ankle brachial index compared to 0-1 risk factors were 5.79 (95% confidence interval [CI]: 2.99-11.20) for 2 risk factors and 17.45 (95% CI: 6.78-49.91) for 3 or more risk factors; independently of other risk factors, the odds ratio for CRP>1.0 mg/l was 2.10 (95% CI: 1.13-3.88) compared to lower CRP values. Thus, a high level of CRP is related to a low ankle brachial index among Japanese elderly as well as Western subjects. This is the first study to report the relationship between CRP and low ankle brachial index among Japanese elderly.  相似文献   
36.
Fluoride and abrasives in toothpastes may cause corrosion and deterioration of the titanium used for implants and other prostheses. The purpose of this study was to investigate how the presence or absence and types of fluoride and abrasives affected the titanium surface texture. Brushing with toothpastes was performed on pure-titanium discs using an abrasive testing machine. Unprocessed titanium discs without brushing were used as control samples. Surface roughness, color, and gloss of titanium were measured and the differences compared with the control were analyzed. Additionally, titanium surfaces and abrasives in toothpastes were observed using a scanning electron microscope to compare the surface texture of each sample. Some toothpastes (abrasive+) significantly increased the difference in surface roughness, color, and gloss, compared with ultrapure water. Toothpaste (fluoride+/abrasive+) that had many polygonal abrasive particles led to the largest color differences and exhibited notable scratches and a larger number of contaminant- or corrosion-like black spots. In contrast, brushing with toothpaste without fluoride or abrasives (fluoride−/abrasive−) caused little change to the titanium surface. These results suggest that both fluoride and abrasives in toothpaste used for brushing may be factors that affect surface texture and corrosion resistance of titanium.  相似文献   
37.
Tripartite motif protein 29 (TRIM29) is one of the TRIM family proteins, some of which function as E3 ubiquitin ligases. In this study, we investigated the usefulness of TRIM29 for diagnosis of prostate cancer. Prostate tissues including carcinoma and non-carcinoma tissues obtained by needle biopsy and radical prostatectomy were used. Immunohistochemistry was performed according to standard procedures using an antibody against TRIM29. Immunohistochemical staining with an antibody against 34βE12, which recognizes cytokeratins 1, 5, 10 and 14, was performed as a control. Basal cells of normal prostatic glands were stained with anti-TRIM29 antibody in all cases, whereas prostate cancer tissues had no or little staining with anti-TRIM29 antibody. TRIM29 is selectively expressed in basal cells of the normal prostate gland, and immunohistochemical staining with anti-TRIM29 antibody showed the same expression pattern as that with 34βE12 in prostate cancer and its benign mimics. Our data indicate that TRIM29 may be useful for distinguishing prostate cancers from benign tissues.  相似文献   
38.
First-degree relatives of persons with thyroid cancer are known to be at relatively high risk for the disease. To better understand the clinicopathologic characteristics of familial nonmedullary thyroid carcinoma (FNMTC), we carried out a retrospective study in which we identified individuals treated at our institution who had at least one first-degree relative with the disease. We used data obtained from our patient records to compare the features of 258 cases of the disease with the features of sporadic papillary or follicular thyroid carcinoma in another group of patients. The 258 patients represented 154 families and were selected from among 6458 patients with papillary or follicular thyroid carcinoma who underwent thyroidectomy between 1946 and 2000. Compared to the patients with sporadic disease, the FNMTC patients were more likely to have intraglandular dissemination (28.5% vs. 40.7%; p < 0.0001) and multiple benign nodules (29.8% vs. 41.5%; p <0.0001). There were no significant differences between the two types of patients in terms of gender, age, tumor diameter, adhesion to or invasion of the surrounding tissues, macroscopic metastasis observed at surgery, histology, presence of single benign nodules, presence of chronic thyroiditis, microscopic metastasis, or rate of lymph node metastasis. Recurrence was statistically frequent in the FNMTC patients compared with that in the sporadic disease patients (16.3% vs. 9.6%; p = 0.0005), and the disease-free survival rate was significantly poorer in the FNMTC patients (p = 0.0041 by the Wilcoxon test and p <0.0001 by the log-rank test). No significant difference in the overall survival rate was found between the two groups. Multivariate analysis by Cox’s proportional hazards method showed FNMTC to be an independent predictor of shorter disease-free survival (risk ratio 1.88; confidence interval 1.35–2.54; p = 0.0003). Locoregional recurrence in the ipsilateral or contralateral lymph nodes and contralateral thyroid lobe was significantly more frequent in the FNMTC patients than in the sporadic disease patients, whereas no difference was found regarding distant metastases. We conclude that FNMTC is a clinically distinct entity with an aggressive nature. Because of the frequent presence of benign nodules, multifocality, and high rate of locoregional recurrence, total or near-total thyroidectomy with modified radical neck dissection in FNMTC patients is recommended.  相似文献   
39.
Objectives: Ischemic mitral regurgitation results from annular dilatation, leaflet tethering and leaflet flattening. Undersized annuloplasty corrects annular dilatation but worsens leaflet tethering and flattening. This exacerbation of abnormal leaflet geometry may contribute to poor repair results for ischemic mitral regurgitation (IMR). Using a sheep model of IMR, we hypothesized that posterior leaflet augmentation and less-extreme annular undersizing would relieve tethering and increase leaflet curvature. Methods: Eight weeks after posterolateral infarct, 10 sheep with ≥2+ IMR underwent either a 24-mm planar ring annuloplasty (n = 5) or a 30-mm planar ring annuloplasty with concomitant posterior leaflet augmentation (n = 5). Real-time three-dimensional echocardiography allowed measurement of indices of leaflet curvature and tethering before and after annuloplasty. Results: Comparing pre- and post-repair values in the P1, P2, and P3 leaflet regions, undersized 24-mm ring annuloplasty made no significant difference to mean septolateral curvature (0.23–0.26, 0.33–0.29, and 0.27–0.37 cm−1, respectively), whereas leaflet augmentation in combination with a 30-mm ring annuloplasty increased septolateral curvature (P1 0.30–1.02, P2 0.31–1.23, and P3 0.35–0.84 cm−1, p-values < 0.05). The mean tethering angle formed between the annular plane and the posterior leaflet increased in all three posterior regions for the 24-mm ring group (P1 12–23°, P2 26–31°, and P3 16–25°), but decreased in all regions for the group undergoing leaflet augmentation (P1 +5 to −6°, P2 +13 to −13°, P3 +16-15°, all p-values < 0.05). Conclusions: Undersized annuloplasty exacerbates leaflet tethering. Posterior leaflet augmentation with less severe annular reduction increases leaflet curvature and decreases tethering; this technique more completely addresses the pathogenic mechanism of IMR and may improve repair durability.  相似文献   
40.
Our purpose was to determine the effect of ovariectomy on intracellular Ca2+ mobilization and platelet aggregation in sodium induced hypertension. At the age of 12 weeks ovariectomy or sham operation was performed in female Dahl-Iwai salt sensitive rats on a 0.3% NaCl diet. Four weeks later we assessed the effects of ovariectomy and an 8% NaCl diet on agonist induced intracellular Ca2+ mobilization in fura-2 loaded platelets and platelet aggregation. Ovariectomy enhanced the increase of systolic blood pressure and heart to body weight ratio on an 8% NaCl diet. However, thrombin evoked intracellular Ca2+ was not correlated with systolic blood pressure (r = −0.338, P = .17), and was lowered by sodium loading and ovariectomy (360 ± 23 to 285 ± 9, 296 ± 10 nmol/L, P < .05). Furthermore, the ionomycin induced intracellular calcium fraction in the absence of external Ca2+ that reflected internal Ca2+ discharge capacity was reduced in ovariectomized rats compared with sham operated rats on an 8% NaCl diet (648 ± 15 v 768 ± 35 nmol/L, P < .05). The internal Ca2+ discharge capacity was inversely correlated with systolic blood pressure (r = −0.506, P = .03). In addition to the decreased internal Ca2+ discharge capacity, intracellular Ca2+-independent platelet aggregation by phorbol 12-myristate 13-acetate, a protein kinase C activator, was significantly enhanced in hypertensive rats. We concluded that ovariectomy enhanced sodium induced hypertension associated with the decreased internal Ca2+ discharge capacity and increased platelet aggregation in Dahl-Iwai salt-sensitive rats.  相似文献   
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