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141.
This study was performed to investigate differences in the shape of the individual palatal rugae in two population samples of Arabian children from Egypt and Saudi Arabia, and develop discriminant function to identify the populations based on rugae shape. A total of 152 stone casts (80 from Egyptian and 72 from Saudi children), equally distributed between genders aged 6–8 years were examined for rugae shape (straight, wavy, curved, circular, unification and cross-link) and their incidence was recorded. Association between rugae shape and gender as well as rugae shape and population were tested using chi-square and discriminant function analyses using SPSS 13 statistical package. Curved and wavy were the most prevalent rugae shape in both groups, followed by straight rugae. Circular, converged and diverged unifications were few in number, while cross-link rugae were not observed in Saudi children. No significant gender differences were observed. Chi-square analysis for association between rugae shape and population groups showed significant differences in curved, wavy, cross-link, converged and diverged unification. Three rugae shapes; wavy, diverging unification and cross-link contributed to the discriminant function which enabled population identification. It was concluded that palatal rugae shape revealed significant differences between the two Egyptian and Saudi populations and also confirmed previous reports of lack of gender dimorphism. Discriminant function analysis allowed differentiation of the populations and it is inferred that discrete variables such as rugae shape are better suited for that purpose than continuous variables such as rugae length.  相似文献   
142.
Dendritic cells (DCs) regulate both immunity and tolerance. Here we have shown that the ubiquitin editing enzyme A20 (Tnfaip3) determines the activation threshold of DCs, via control of canonical NF-κB activation. Tnfaip3(fl/fl)Cd11c-cre(+) mice lacking A20 in DCs demonstrated spontaneous proliferation of conventional and double-negative T?cells, their conversion to interferon-γ (IFN-γ)-producing effector cells, and expansion of plasma cells. They developed ds-DNA antibodies, nephritis, the antiphospholipid syndrome, and lymphosplenomegaly-features of systemic lupus erythematosus-and extramedullary hematopoiesis. A20-deficient DCs were resistant to apoptosis, caused by increased sensitivity to CD40L and RANKL prosurvival signals and upregulation of antiapoptotic proteins Bcl-2 and Bcl-x. They captured injected apoptotic cells more efficiently, resisted the inhibitory effects of apoptotic cells, and induced self-reactive effector lymphocytes. Because genetic polymorphisms in TNFAIP3 are associated with human autoimmune disorders, these findings identify A20-mediated control of DC activation as a crucial checkpoint in the development of systemic autoimmunity.  相似文献   
143.
Apart from genetics, nutrition, and environment, occupational factors also play an important role in colon and rectal cancer development. The aim of this study was to examine these cancer types in an area of former coal, iron, and steel industries, which was found to display an increased incidence of colon cancer mortality. N-Acetyltransferase 2 (NAT2) and glutathione S-transferase M1 (GSTM1) genotypes were investigated in 108 colon cancer cases, 80 rectum cancer cases, and 188 controls (suffering from nonmalignant diseases). Further, in a pilot study, 28 colorectal cancer patients were NAT2 phenotyped by the caffeine test. Possible occupational and nonoccupational risk factors were investigated by a personal interview. The frequency of rapid NAT2 genotype was 35% in colon cancer cases, 47% in rectal cancer cases, and 42% in controls (GSTM1 0/0 genotype: 53, 46, and 47%, respectively). In the 29 patients with cancer in the ascending colon, 10% were of the rapid NAT2 genotype. In the pilot study the frequency of the rapid NAT2 phenotype was 49%. The only major professional group with an elevated risk was painters (colon cancer OR 2.48, 95% CI 0.4-15.23; rectal cancer OR 5.65, 95% CI 1.06-30.21). In contrast to early studies, in the present study the slow NAT2 status is overrepresented. As colorectal cancer is associated with nutrition and physical activity, present findings may be due to excessive physical heavy work and the resulting nutrition in this area.  相似文献   
144.
This study aimed to evaluate oxidative stress and apoptosis in childhood acute lymphoblastic leukemia (ALL) at diagnosis and their impact on outcome at the end of the induction phase. Our study included 50 newly diagnosed children with ALL. Evaluation of oxidative stresses (malondialdehyde and total anti-oxidant capacity) was made at diagnosis and at the end of the induction phase. Apoptosis level was determined by fluorometric terminal deoxynucleotidyl transferase dUTP nick end labeling system for patients at diagnosis and after 1 week of treatment. Our study showed that there was increased oxidative stress at diagnosis and after treatment with chemotherapy. Apoptosis index was higher after 1 week of treatment with chemotherapy when compared to its level at diagnosis.  相似文献   
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146.

OBJECTIVE

To develop and validate an Arabic version of the International Prostate Symptom Score (IPSS).

PATIENTS, SUBJECTS AND METHODS

An Arabic version of the IPSS (IPSS‐Arb) was developed through a series of translations and modifications which involved the authors, urology and non‐urology medical and nursing staff. The validity and reliability were assessed in 76 patients with urinary symptoms due to benign prostatic hyperplasia (BPH) and in 63 control subjects without BPH; 25 patients had transurethral resection of prostate (TURP) whereas the remaining 51 patients were treated with terazosin. The reliability of the IPSS‐Arb was assessed by determining the internal consistency (Cronbach’s α coefficient) and by assessing the test‐retest reliability (intraclass correlation coefficient, ICC). Construct validity was assessed by determining the correlation between the IPSS‐Arb scores and the quality‐of‐life question (QoL‐Arb), and by determining the ability of the IPSS‐Arb to discriminate between the patients and controls by calculating the area under the receiver operating characteristic (ROC) curve.

RESULTS

The Cronbach’s α coefficient (internal consistency) for the IPSS‐Arb was 0.85, and 0.78–0.88 for the individual items. The test‐retest reliability (ICC) was 0.88 (P < 0.001). In addition, the IPSS‐Arb had a high correlation with the QoL‐Arb (Spearman rank correlation coefficient 0.82, P = 0.01). The mean (sem , 95% confidence interval) area under the ROC curve for the IPSS‐Arb was 0.93 (0.09, 0.89–0.97), whereas the area for its individual questions was 0.79–0.90. The IPSS‐Arb also showed a high sensitivity to change. The mean (sd ) IPSS‐Arb scores before and after TURP were 23.1 (6.4) and 6.9 (1.8), respectively (P < 0.001); in the terazosin group, the scores were 12.6 (7.4) and 8.2 (4.0), respectively (P < 0.001).

CONCLUSIONS

The IPSS‐Arb was shown to be a reliable and valid instrument for patients with BPH. We recommend using it for patient assessment and follow‐up, and as a research tool in Arabic‐speaking patients both in the Middle East and worldwide. In addition, this study provided another proof of the wide suitability of the IPSS among various nations worldwide.  相似文献   
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149.
The aim of this study was to measure the remaining filling volume of different obturation materials from root-filled extracted teeth by using 2 removal techniques. Eighty single-rooted teeth were collected and decoronated, and the root canal was prepared by using the ProTaper nickel-titanium rotary files. The teeth were randomly allocated into 4 groups, and each group was obturated by using a different material. Group 1 was filled with gutta-percha and TubliSeal sealer, group 2 was filled with EndoRez points and EndoRez sealer, group 3 was filled with RealSeal points and RealSeal sealer, and Group 4 was filled with a gutta-percha point and GuttaFlow sealer. Teeth were scanned with a micro-computed tomography scan, and then root fillings were removed by using ProTaper retreatment files or hand K-files. Teeth were scanned again, and volume measurements were carried out with micro-computed tomography software. Statistical analysis showed significant differences between the 2 removal techniques for gutta-percha and for both techniques between gutta-percha and the other groups. The present study showed that all tested filling materials were not completely removed during retreatment by using hand or rotary files. Gutta-percha was more efficiently removed by using hand K-files.  相似文献   
150.
Purpose: To evaluate the feasibility of translating the Diabetes Prevention Program (DPP) lifestyle intervention into practice in a rural community. Methods: In 2008, the Montana Diabetes Control Program worked collaboratively with Holy Rosary Healthcare to implement an adapted group-based DPP lifestyle intervention. Adults at high risk for diabetes and cardiovascular disease were recruited and enrolled (N = 101). Participants set targets to reduce fat intake and increase physical activity (≥150 mins/week) in order to achieve a 7% weight loss goal. Findings: Eighty-three percent (n = 84) of participants completed the 16-session core program and 65 (64%) participated in 1 or more after-core sessions. Of those completing the core program, the mean participation was 14.4 ± 1.6 and 3.9 ± 1.6 sessions during the core and after core, respectively. Sixty-five percent of participants met the 150-min-per-week physical activity goal during the core program. Sixty-two percent achieved the 7% weight loss goal and 78% achieved at least a 5% weight loss during the core program. The average weight loss per participant was 7.5 kg (range, 0 to 19.7 kg), which was 7.5% of initial body weight. At the last recorded weight in the after core, 52% of participants had met the 7% weight loss goal and 66% had achieved at least a 5% weight loss. Conclusion: Our findings suggest that it is feasible to implement a group-based DPP in a rural community and achieve weight loss and physical goals that are comparable to those achieved in the DPP.  相似文献   
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