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141.
This study investigated the effect of resin coating and occlusal loading on adhesion and microleakage of all-ceramic crowns. Molars were prepared for an all-ceramic crown and were divided into two groups: non-coated (control) and resin-coated with Clearfil Tri-S Bond. Crowns were fabricated using CEREC 3 and cemented using Clearfil Esthetic Cement. After 24 h of storage in water, the restored teeth in each group were divided into two subgroups: unloaded, or loaded while stored in water. Mechanical loading was achieved with an axial force of 80 N at 2.5 cycles s−1 for 250,000 cycles. After immersion in Rhodamine B, the specimens were sectioned and processed for microleakage evaluation by confocal microscopy, which was followed by further sectioning for microtensile bond testing. Loading had no significant effect on microleakage in either the resin-coated or non-resin-coated groups. Resin coating did not reduce the microleakage at the dentine interface but increased the microleakage at the enamel interface. All the beams fractured during slicing when non-coated and loaded. The bond strengths of non-coated and unloaded, resin-coated and unloaded, and resin-coated and loaded groups were 15.82 ± 4.22, 15.17 ± 5.24, and 12.97 ± 5.82 MPa, respectively. Resin coating with Clearfil Tri-S Bond improved the bonding of resin cement to dentine for loaded specimens. However, it was not effective in reducing the microleakage, regardless of whether it was loaded or unloaded.  相似文献   
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143.
Immunoglobulin kappa gene usage and somatic mutation patterns were studied in a series of 47 IGKV-J rearrangements amplified in 42 follicular lymphoma (FL) cases. The IGKV1-39/1D-39 gene predominated and was significantly over-represented compared to normal cells, autoreactive cells or other B cell lymphomas. The impact of somatic hypermutation varied significantly; nevertheless, mutation distribution patterns indicated pressure for preservation of the B cell receptor. In conclusion, the present series demonstrates biased usage of IGKV genes in FL and alludes to the important role of immunoglobulin kappa light chains in antigen selection of the clonogenic B cells in FL.  相似文献   
144.
145.
Worldwide, colon cancer is among the most common cancer entities. Understanding the molecular background is the key to enable accurate stage determination, which is crucial to assess optimal therapy options. The search for preoperative biomarkers is ongoing. In recent years, several studies have proposed a diagnostic and prognostic role for miRNAs in cancer. Aim of this study was to evaluate miRNA expression patterns correlating with tumor stage, especially lymph node metastasis, in primary colon carcinoma tissue. Screening was accomplished using GeneChip® miRNA v3.0 arrays (Thermo Fisher Scientific, Waltham, MA, USA) and validated via TaqMan® qPCR assays (Thermo Fisher Scientific, Waltham, MA, USA) to investigate miRNA expressions in 168 FFPE and 83 fresh frozen colon carcinoma samples. Regarding lymph node status, analyses displayed no significantly differential miRNA expression. Interestingly, divergent expression of miR-18a-5p, miR-20a-5p, miR-21-5p, miR-152-3p and miR-1973 was detected in stage pT1. Although miRNAs might not represent reliable biomarkers regarding lymph node metastasis status, they could support risk assessment in stage T1 tumors.  相似文献   
146.
Research questionDo women with polycystic ovary syndrome (PCOS) have higher testosterone levels during pregnancy and what role does high testosterone play in the development of obstetric complications?DesignRetrospective cohort study from Uppsala University Hospital, Sweden. The study population consisted of women with PCOS (n = 159) and a comparison group of women without PCOS matched for body mass index (n = 320). Plasma testosterone levels were measured in the early second trimester by liquid chromatography with tandem mass spectrometry, and women with PCOS were grouped into tertiles according to their testosterone levels. Possible associations with obstetric complications, maternal metabolic factors and offspring birth weight were explored by multivariable logistic and linear regression models.ResultsCompared with women who do not have PCOS, women with PCOS had higher total testosterone (median 1.94, interquartile range [IQR] 1.21–2.64 versus 1.41, IQR 0.89–1.97; P < 0.001), and free androgen index (median 0.25, IQR 0.15–0.36 versus 0.18, IQR 0.11–0.28; P < 0.001). Women with PCOS who had the highest levels of testosterone had increased risk for preeclampsia, even when adjusted for age, parity, country of birth and smoking (adjusted OR 6.16, 95% CI 1.82 to 20.91). No association was found between high testosterone in women with PCOS and other obstetric complications.ConclusionsWomen with PCOS have higher levels of total testosterone and free androgen index during pregnancy than women without PCOS matched for body mass index. Preliminary evidence shows that women with PCOS and the highest maternal testosterone levels in early second trimester had the highest risk of developing preeclampsia. This finding, however, is driven by a limited number of cases and should be interpreted with caution.  相似文献   
147.
Research of the role of religious belief and/or spirituality has been conducted on a wide range of health‐related topics, across many disciplines, and in many countries. The purpose of this study was to determine the relationship between religious beliefs, self‐esteem, anxiety, and depression in nursing students in Cyprus. One hundred and twenty‐three nursing students were asked to complete a survey consisting of four self‐report questionnaires (Beck Depression Inventory, State–Trait Anxiety Inventory, The Royal Free Interview for Religious and Spiritual Beliefs, and Rosenberg Self‐esteem Scale). The lowest levels of depression were observed in the third and fourth study year. Normal self‐esteem levels were found in the majority of the students (71.3%) and most of them perceived current stress at mild levels. No significant differences on the basis of sex were observed. The vast majority (98.2%) of the students stated a strong religious and/or a spiritual belief that was strongly positively correlated with increased self‐esteem and negatively correlated with depression, current stress, and stress as personality trait.  相似文献   
148.
149.
A mutation in the peroxisome proliferator-activated receptor gamma2 (PPARgamma2) gene with a cytosine to guanine substitution results in an exchange of proline (Pro) with alanine (Ala) in exon B (codon 12) of this gene. This polymorphism has been associated with high insulin sensitivity and low body weight, but no data have been published to date about its effect on early atherosclerosis. We investigated the relationship of the Pro(12)Ala polymorphism to early atherosclerosis, measured by the intima-media thickness (IMT). A total of 622 subjects were included, aged 40-70 yr, who were participants of the RIAD (Risk factors in Impaired glucose tolerance for Atherosclerosis and Diabetes) study and were at risk of developing type 2 diabetes. Altogether, 449 of the subjects had the common genotype (Pro(12)Pro), 162 had the Pro(12)Ala genotype, and 11 the Ala(12)Ala genotype. IMT was significantly decreased in subjects with the Ala(12)Ala genotype compared with subjects with the other two genotypes. Body mass index, free fatty acid levels, and leukocyte count were lower in subjects with the Ala(12)Ala genotype compared with subjects with the Pro(12)Pro or Pro(12)Ala genotypes. In multivariate analysis, the Ala(12)Ala genotype was a significant independent determinant of IMT. Furthermore, we demonstrated specific expression of the PPARgamma2 gene in human atherosclerotic lesions as well as in cultured primary macrophages and foam cells. In conclusion, our data suggest that the Ala(12)Ala genotype of the PPARgamma2 gene may protect from early atherosclerosis in subjects at risk for diabetes.  相似文献   
150.

Objectives

To compare in a randomized, controlled trial the clinical effectiveness of care delivered by a clinical nurse specialist, inpatient team care, and day patient team care in patients with rheumatoid arthritis (RA) who have increasing functional limitations.

Methods

Between December 1996 and January 1999, 210 patients with RA were recruited in the outpatient clinic of the rheumatology department of 6 academic and nonacademic hospitals. Clinical assessments recorded on study entry and weeks 6, 12, 26, and 52 included the Health Assessment Questionnaire (HAQ) and the McMaster Toronto Arthritis Patient Preference Disability Questionnaire as primary outcome measures, and the RAND‐36 Item Health Survey, the Rheumatoid Arthritis Quality of Life questionnaire, the Health Utility Rating Scale, and the Disease Activity Score as secondary outcome measures. Patient satisfaction with care was measured on a visual analog scale in week 6 in all 3 groups and again in week 12 in the nurse specialist group.

Results

Within all 3 groups, functional status, quality of life, health utility, and disease activity improved significantly over time (P < 0.05). However, a comparison of clinical outcome among the 3 groups and a comparison between the nurse specialist group and the inpatient and day patient care groups together did not show any sustained significant differences. Subgroup analysis showed that age had a significant impact on differences between the 3 treatment groups with respect to functional outcome as measured with the HAQ (P < 0.001). With increasing age, the most favorable outcome shifted from care provided by a clinical nurse specialist and inpatient care to day patient care. Patients' satisfaction with care was significantly lower in the nurse specialist group than in the inpatient and day patient care groups (P < 0.001).

Conclusion

Care provided by a clinical nurse specialist appears to have a similar clinical outcome in comparison with inpatient and day patient team care. Although all patients were highly satisfied with multidisciplinary care, patients who received care provided by a clinical nurse specialist were slightly less satisfied than those who received inpatient or day patient team care. Age appeared to be the only factor related to differences in functional outcome between the 3 treatment groups. The choice of management strategy may, apart from age, further be dependent on the availability of facilities, the preferences of patients and health care providers, and economic considerations.
  相似文献   
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