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1.
This paper describes and analyzes a proposed solution of fundamental limitative factor of teleradiology to overcome the teleradiology usages problems in underdeveloped and developing countries. The goal is to achieve a very simple and cost-efficient way to take advantage of teleradiology in anywhere even in remote and rural areas. To meet the goal of this study, the following methodology which is consists of two main procedures was done: (1) Using a digital camera in order to provide a digital image from radiographs. (2) Using an image compression tool in order to compress digital images. The results showed that there is no significant difference between digital images (non-compress and compress images) and radiographic films. Also, there was a logic relationship between the diagnostic quality and diagnostic accuracy. Since the maximum percent of diagnostic accuracy can be seen among “Good” quality images and the minimum to was related “Poor”. The results of our study indicate that a digital camera could be utilized to capture digital images from radiographic films of chest x-ray. To reduce the size of digital images, a lossy compression technique could be applied at compression percent of 50 or less without any significant differences. The compressed images can be sent easily by email to other places for consultation and also they can be stored with a smaller size.  相似文献   
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OBJECTIVE: To determine whether leptin secretion is impaired in diabetes, we compared basal and stimulated plasma leptin levels in diabetic subjects and healthy controls. RESEARCH METHODS AND PROCEDURES: Blood samples for assay of leptin and other hormones were obtained at baseline in 54 diabetic patients and 65 controls, and 8 hours, 16 hours, and 40 hours following ingestion of dexamethasone (4 mg) in 6 healthy and 12 controls. C-peptide status was defined as "negative" if < or =0.1 ng/mL or "positive" if > or =0.3 ng/mL, in fasting plasma. RESULTS: Basal plasma leptin levels were 19.7+/-2.2 ng/mL in nondiabetic subjects, 13.4+/-1.5 ng/ml in C-peptide negative (n = 28) and 26.1+/-3.7 ng/mL in C-peptide positive (n = 26, p = 0.001) diabetic patients. Dexamethasone increased leptin levels of controls (n = 6) to 145+/-17% of baseline values at 8 hours (p = 0.03), 224+/-18% at 16 hours (p = 0.01), and 134+/-18% at 40 hours (p=0.05). The corresponding changes were 108+/-13%, 126+/-23%, and 98+/-16% in C-peptide negative (n=6), and 121+/-10%, 144+/-16% (p=0.03), and 147+/-23% (p=0.11) in C-peptide positive (n = 6) diabetic patients, respectively. The peak stimulated leptin levels were lower in the diabetic patients, compared with controls. Plasma insulin increased (p = 0.02) in controls, but not in the diabetic patients, following dexamethasone. DISCUSSION: Although diabetic patients have normal plasma leptin levels under basal conditions, their leptin responses to glucocorticoid are impaired, probably because of the concomitant insulin secretory defect. A subnormal leptin secretory response could worsen obesity and insulin resistance in diabetes.  相似文献   
3.
The authors developed a union sponsored 2-day human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) "train the trainer" program for healthcare workers in the San Francisco Bay Area. The program incorporated the "education for action" approach in an effort to respond to the inadequacies in many traditional, institutional trainings. Service Employees International Union (SEIU) and Labor Occupational Health Program (LOHP) conducted the HIV/AIDS "train the trainer" program for approximately 100 healthcare workers in county public hospitals and community health clinics. After completing the program, these workers went back to their healthcare facilities, or community organizations, and led additional classes on HIV/AIDS transmission and prevention for approximately 600 more people. The goal of the program was to empower healthcare workers to: 1) identify the occupational risks associated with exposure to blood and potentially infectious body fluids at the workplace; 2) develop strategies to reduce those risks; 3) discuss their feelings about caring for an HIV/AIDS patient; and, 4) conduct HIV/AIDS workshops at the workplace.  相似文献   
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The choice of casarean deliveries by mothers is highly influenced by inadequate knowldge and negative attitudes towards vaginal birth. In this semi-experimental study, we compared knowledge, attitude, and decision making about modes of delivery between nulliparous pregnant women who received eight sessions of group consultation and those who took routine prenatal education. Contrary to the control group, the improvement of knowledge and attitudes were significant in the consultation group (p < 0.001), as well as mothers' decisions for vaginal birth (p = 0.03). Group consultation is an appropriate approach to improving knowledge, attitudes, and tendencies of mothers toward natural birth.  相似文献   
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Aim

To assess the association between obesity and risk of migraine with aura and features of migraine attacks among a population of Iranian adults.

Methods

In this case-control study, 102 confirmed cases of migraine with aura were matched based on age and gender with 102 healthy subjects. Data on demographic characteristics and anthropometric measurements were collected from all cases and controls by the same methods. Overweight and obesity were considered as body mass index ≥25–30?kg/m2 and?≥?30?kg/m2, respectively. Features of migraine attacks including frequency, duration and headache daily result were determined for patients based on international headache society criteria.

Results

Mean age of subjects was 34.5?±?7.4 years and 77.9% of them were female. Compared with subjects with normal body mass index, those with obesity had greater odds for having migraine with aura (OR: 3.06, 95% CI: 1.11–8.43). Such finding was also seen even after adjusting for confounding variables; in a way that subjects with obesity were 2.92 times more likely for having migraine with aura compared with those with normal weight (OR: 2.92, 95% CI: 1.03-8.33). Among migraine with aura patients, we found that those with obesity had higher headache daily result compared with subjects with normal weight. However, obesity was not associated with frequency and duration of migraine attacks.

Conclusions

We found that obesity was positively associated with risk of migraine with aura. In addition, subjects with obesity had higher headache daily result compared with those with normal weight.  相似文献   
9.
A patient manifesting the arthropathy of hemochromatosis without abnormal serum iron studies is described. Hemochromatosis was confirmed by liver biopsy. This case serves to emphasize the diagnostic value of the characteristic arthropathy of hemochromatosis. Our observations in this patient support the hypothesis that the pathogenesis of hereditary hemochromatosis differs from that of acquired iron overload states. The concurrent presence of hypouricemia is explored in this patient and in 18 other patients with hereditary hemochromatosis. Men with hereditary hemochromatosis were found to have lower serum uric acid levels than expected. In our patient, a renal defect in tubular reabsorption of uric acid appears responsible for hypouricemia.The apparent association of hemochromatosis and hypouricemia deserves further investigation.  相似文献   
10.
Isolated myocytes of rat heart, and sealed sarcolemmal vesicles of bovine heart, were used to examine the selectivity of the effects of partially reduced oxygen species (generated by a mixture of xanthine and xanthine oxidase) on cardiac sodium pump and several other ion transporters of the plasma membrane. When myocytes were exposed to xanthine plus xanthine oxidase, there were time-dependent inhibitions of ouabain-sensitive 86Rb+ uptake and (Na+ + K+)-ATPase activity that could be prevented by allopurinol, or by catalase and superoxide dismutase; suggesting the involvements of H2O2 or oxygen free radicals in the inhibition of the pump. This inhibition preceded any significant decrease in cellular ATP or in the number of viable cells. While ouabain increased 45Ca2+ uptake by myocytes as expected, exposure to xanthine plus xanthine oxidase decreased 45Ca2+ uptake; suggesting that the Na+, Ca2(+)-exchanger of the intact myocytes is also inhibited by oxygen metabolites. Simultaneous inhibitions of the pump, the Na+, Ca2(+)-exchange, the Na+, H(+)-exchange, and the Na+, Pi-cotransport activities also occurred in sarcolemmal vesicles that were treated with xanthine plus xanthine oxidase. These findings indicate that inactivations of the sodium pump and other sarcolemmal ion carriers are early events in the oxidant-induced damage to the cardiomyocyte. In the rat heart myocytes, a fraction of (Na+ + K+)-ATPase that seems to be more sensitive to ouabain, was inactivated more rapidly upon exposure of myocytes to xanthine plus xanthine oxidase; raising the possibility of the existence of different pump populations with different sensitivities to extracellularly generated oxygen metabolites.  相似文献   
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