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Quality control is the application of statistical techniques to a process in an effort to identify and minimize both random and non-random sources of variation. The present study aimed at the application of Statistical Process Control (SPC) to analyze the referrals by General Practitioners (GP) at Health Insurance Organization (HIO) clinics in Alexandria. Retrospective analysis of records and cross sectional interview to 180 GPs were done. Using the control charts (p chart), the present study confirmed the presence of substantial variation in referral rates from GPs to specialists; more than 60% of variation was of the special cause, which revealed that the process of referral in Alexandria (HIO) was completely out of statistical control. Control charts for referrals by GPs classified by different GP characteristics or organizational factors revealed much variation, which suggested that the variation was at the level of individual GPs. Furthermore, the p chart for each GP separately; which yielded a fewer number of points out of control (outliers), with an average of 4 points. For 26 GPs, there was no points out of control, those GPs were slightly older than those having points out of control. Otherwise, there was no significant difference between them.The revised p chart for those 26 GPs together yielded a centerline of 9.7%, upper control limit of 12.0% and lower control limit of 7.4%. Those limits were in good agreement with the limits specified by HIO; they can be suggested to be the new specification limits after some training programs.  相似文献   
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Background and study aimsBoth hepatitis C virus (HCV) and schistosomiasis are highly endemic in Egypt and coinfection is frequently encountered. Such coinfection is responsible for leading to a more severe liver disease. Hence, the aim of the study was to assess the fibroscan in chronic HCV patients coinfected with Schistosoma.Patients and methodsThis study included 231 chronic HCV patients. Routine pre-treatment work-up was done including anti-schistosomal antibodies. Liver stiffness measurements using fibroscan and reference needle-liver biopsy were done. Patients were categorised into two groups: HCV patients with positive schistosomal serology and HCV patients with negative schistosomal serology.ResultsAnti-schistosomal antibody was positive in 29% of the studied population. Positive schistosomal serology status was significantly associated with the disagreement between the results of liver biopsy (Metavir) and the fibroscan results (p value = 0.02), which was more obvious in F2 and F3 fibrosis stages. The sensitivity of fibroscan for the detection of the F2 stage decreased from 64% among negative schistosomal serology patients to 30.8% among positive schistosomal serology patients, and for the F3 stage it decreased from 43.8% to 21.4%, respectively. Multivariate logistic regression showed that fibrosis stages (F0–F1 and F4) were the most independent factors that were associated with the agreement between fibroscan and liver biopsy (odds ratio (OR) 3.4, 7.12 and p value <0.001, <0.001, respectively).ConclusionAlthough the sensitivity of fibroscan for the detection of fibrosis stages (F2 and F3) was impaired in patients with positive schistosomal serology, fibrosis stages (F0–F1 and F4) were the most independent factors associated with the agreement between fibroscan and liver biopsy.  相似文献   
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Background: Osteoporosis (OP) is a growing health problem not only in women but also in men. Subjects and methods: This study was carried out on 100 healthy men, age range 30–65 years (mean ± SD, 44.65 ± 8.3). All were randomly recruited from Assiut city during the period January 2005 to January 2006. Complete clinical history included occupational history, smoking habit, physical activity and calcium intake. Complete clinical examination and anthropometric measurments were done. Laboratory investigations for serum calcium, phosphorus and osteocalcin were performed. Bone mineral density (BMD) was measured by calcaneal ultrasound. Results: Sixty‐three percent of participants had normal BMD, 37% had low BMD, (26% had quantitative bone ultrasound [QUS] T‐score –1 to –2.5 and 11% had QUS T‐score ≤ –2.5). Smoking and low physical activity were risk factors for low BMD. Significant positive correlations were found between BMD and body mass index, serum calcium, and osteocalcin and negative correlation with phosphorus. We concluded that low BMD occurs with high frequency in Egyptian men. Smoking, physical inactivity and low body index are significant risk factors. Low serum calcium, low serum osteocalcin and high serum phosphorus are biochemical risk factors of low BMD in males.  相似文献   
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Research efforts are being made to identify personality and cognitive variables predictive of poor adjustment following myocardial infarction. Sixty-two male patients were examined after a first and uncomplicated myocardial infarction to determine whether dispositional emotional reactivity and debilitating beliefs measured during hospitalization can predict work engagement, social activities involvement, and ambulation/independence six months later. A structural model with direct paths between emotional reactivity, debilitating beliefs, and the above outcomes, as well as partial mediation of emotional distress and illness preoccupation, was tested using the CALIS procedure. The model explained 33%, 48% and 82% of the variance in the three outcomes, respectively. Work engagement was indirectly related through emotional distress to earlier emotional reactivity and debilitating beliefs. Social activities involvement was both directly and indirectly related through emotional distress to debilitating beliefs; and also indirectly related through emotional distress to emotional reactivity. Ambulation/independence was directly and negatively related to debilitating beliefs. Prolonged emotional distress was predicted by emotional reactivity and debilitating beliefs. Illness preoccupation turned out to be an independent outcome that was positively related to emotional reactivity. Thus, measuring dispositional emotional reactivity and debilitating beliefs at the hospitalization stage may be helpful in detecting patients at risk of poor future adjustment.  相似文献   
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EphA7 is expressed in the adult central nervous system (CNS), where its roles are yet poorly defined. We mapped its distribution using in situ hybridization (ISH) and immunohistochemistry (IHC) combined with light (LM) and electron microscopy (EM) in adult rat and mouse brain. The strongest ISH signal was in the hippocampal pyramidal and granule cell layers. Moderate levels were detected in habenula, striatum, amygdala, the cingulate, piriform and entorhinal cortex, and in cerebellum, notably the Purkinje cell layer. The IHC signal distribution was consistent with ISH results, with transport of the protein to processes, as exemplified in the hippocampal neuropil layers and weakly stained pyramidal cell layers. In contrast, in the cerebellum, the Purkinje cell bodies were the most strongly immunolabeled elements. EM localized the cell surface‐expression of EphA7 essentially in postsynaptic densities (PSDs) of dendritic spines and shafts, and on some astrocytic leaflets, in both hippocampus and cerebellum. Perikaryal and dendritic labeling was mostly intracellular, associated with the synthetic and trafficking machineries. Immunopositive vesicles were also observed in axons and axon terminals. Quantitative analysis in EM showed significant differences in the frequency of labeled elements between regions. Notably, labeled dendrites were ~3–5 times less frequent in cerebellum than in hippocampus, but they were individually endowed with ~10–40 times higher frequencies of PSDs, on their shafts and spines. The cell surface localization of EphA7, being preferentially in PSDs, and in perisynaptic astrocytic leaflets, provides morphologic evidence that EphA7 plays key roles in adult CNS synaptic maintenance, plasticity, or function. J. Comp. Neurol. 524:2462–2478, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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