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81.
A disparity exists in the educational qualifications of dental assistants working in various public and private institutions in Riyadh, Saudi Arabia. The aim of this study was to assess the influence of professional and personal characteristics on job satisfaction among dental assistants. A cross-sectional survey was performed among dental assistants using a 24-item self-administered questionnaire. Multinomial logistic regression was used to assess the relationship between overall job satisfaction and other variables. The overall response rate was 72.1%. Factor analysis suggested that five underlying factors were related to job satisfaction. The mean score for overall job satisfaction was 3.86 (satisfied) out of 5. Among the work environment factors, the highest mean score, 4.26 (satisfied), was obtained for quality of service, and the lowest mean score, 2.78 (neutral), was obtained for the perception of income. The income and general prospects of the profession was significantly associated with overall job satisfaction. This study suggests that for dental assistants, professional and personal life, quality of service, perception of income and prestige and self-respect are important factors for job satisfaction. Despite differences in professional formation standards, in general, the study participants were considerably satisfied with their jobs.  相似文献   
82.
The objectives of this study were to estimate patient dose in some common diagnostic X-ray examinations. Radiation doses were estimated for 307 patients in six public hospitals comprising 7 X-ray units in Wad-madani, Sudan. Entrance surface air kerma (ESAK) was estimated in a three step protocol: First, X-ray unit output Y(d) was measured at a distance, d for different peak tube voltages and tube loadings (mAs). Next, incident air kerma (Ki) was calculated from Y(d) using inverse square law combined with patient exposure factors. ESAK was calculated from Ki using backscatter factor, B. Mean ESAK values are comparable to those reported in other countries and are below reference dose levels. The estimated mean ESAK values are: 0.3, 2.2, 2.2, 2.9, 2.8, 3.1, and 7.5 mGy for chest PA, Skull AP/PA, Skull LAT, Abdomen, Pelvis AP, Lumbar Spine AP and Lumbar Spine LAT examinations, respectively. The results are used for dose optimization, and to propose local diagnostic reference levels.  相似文献   
83.
Suliman A  Lam A  Datta R  Srivastava RK 《Oncogene》2001,20(17):2122-2133
Tumor necrosis (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF family of cytokines that promotes apoptosis. TRAIL induces apoptosis via death receptors (DR4 and DR5) in a wide variety of tumor cells but not in normal cells. The objectives of this study are to investigate the intracellular mechanisms by which TRAIL induces apoptosis. The death receptor Fas, upon ligand binding, trimerizes and recruits the adaptor protein FADD through the cytoplasmic death domain of Fas. FADD then binds and activates procaspase-8. It is unclear whether FADD is required for TRAIL-induced apoptosis. Here we show that the signaling complex of DR4/DR5 is assembled in response to TRAIL binding. FADD and caspase-8, but not caspase-10, are recruited to the receptor, and cells deficient in either FADD or caspase-8 blocked TRAIL-induced apoptosis. In addition, TRAIL initiates the activation of caspases, the loss of mitochondrial transmembrane potential (Deltapsi(m)), the cleavage of BID, and the redistribution of mitochondrial cytochrome c. Treatment of Jurkat cells with cyclosporin A delayed TRAIL-induced Deltapsi(m), caspase-3 activation and apoptosis. Similarly, Overexpression of Bcl-2 or Bcl-X(L) delayed, but did not inhibit, TRAIL-induced Deltapsi(m) and apoptosis. In contrast, XIAP, cowpox virus CrmA and baculovirus p35 inhibited TRAIL-induced apoptosis. These data suggest that death receptors (DR4 and DR5) and Fas receptors induced apoptosis through identical signaling pathway, and TRAIL-induced apoptosis via both mitochondrial-dependent and -independent pathways.  相似文献   
84.
Tumor necrosis (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF family of cytokines that promotes apoptosis. TRAIL induces apoptosis in a wide variety of tumor cells but not in normal cells. Oncogene Bcl-2 can protect cells from apoptosis induced by various stress stimuli. However, it is not clear whether Bcl-2 can regulate TRAIL-induced apoptosis. The objective of this study was to investigate whether Bcl-2 can regulate apoptosis induced by TRAIL. TRAIL initiates the activation of caspases, the loss of mitochondrial transmembrane potential (Delta psi(m)), and the redistribution of mitochondrial cytochrome c. TRAIL has no effect on Delta psi(m) and apoptosis in Jurkat cells deficient in either FADD or caspase-8, suggesting both FADD and caspase-8 are required for TRAIL signaling. Overexpression of Bcl-2 delays, but does not inhibit, TRAIL-induced Delta psi(m), cytochrome c release from mitochondria and apoptosis, whereas etoposide-induced apoptosis is blocked by Bcl-2. XIAP, cowpox virus CrmA and baculovirus p35 inhibits TRAIL-induced apoptosis. These data suggest that TRAIL can be used to kill Bcl-2 positive cells that can not be killed by other class of chemotherapeutic drugs.  相似文献   
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Abstract: The association of aplasia cutis congenita of the scalp with distal malformations of the limbs is known as Adams-Oliver syndrome. Other reported associations include palatine or auricular malformations, cardiovascular alterations, and spina bifida. Multiple hereditary patterns have been described for this condition, and sporadic cases have also been reported. We report an infant with Adams-Oliver syndrome associated with intracranial calcifications in whom no evidence of intrauterine infection could be demonstrated.  相似文献   
89.
Markers of hepatitis A and B virus were tested in 88 adult Sudanese subjects in Khartoum, Sudan. The subjects consisted of 25 control hospitalized patients, 21 volunteer blood donors, 23 patients with hepatosplenic schistosomiasis, 13 patients with liver cirrhosis and 6 patients with hepatocellular carcinoma (HCC). Antibody to hepatitis A virus was detected in 96% of the total. Hepatitis B surface antigen (HBsAg) was positive in 4, 24, 22, 31, and 67% of the subject groups, respectively. Antibody against hepatitis B core antigen (HBcAb) of undiluted serum was positive in 60, 57, 65, 77 and 83%, and there was no difference in incidence among the groups. It was positive in 200X diluted serum in 4, 24, 17, 23 and 60%. HBsAg and HBcAb (200X) were detected more often in HCC patients than in the control subjects (p less than 0.01). Hepatitis B virus is an important factor in the etiology of HCC in the Sudan.  相似文献   
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