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71.
Nowadays, with comprehensive employment of the internet, healthcare delivery services is provided remotely by telecare medicine information systems (TMISs). A secure mechanism for authentication and key agreement is one of the most important security requirements for TMISs. Recently, Tan proposed a user anonymity preserving three-factor authentication scheme for TMIS. The present paper shows that Tan’s scheme is vulnerable to replay attacks and Denial-of-Service attacks. In order to overcome these security flaws, a new and efficient three-factor anonymous authentication and key agreement scheme for TMIS is proposed. Security and performance analysis shows superiority of the proposed scheme in comparison with previously proposed schemes that are related to security of TMISs.  相似文献   
72.
Deaths from infectious diseases and deep concerns about increases in microbial resistance make it necessary for scientists to develop innovative therapeutic solutions and complementary therapies. Growing evidence is available on the therapeutic effects of probiotics. There are also documents about the beneficial effects of probiotics, but it is difficult to draw a definitive conclusion regarding the results of these studies because of the small sample size, the limitations of the study methods, and the use of different strains of probiotic bacteria. This review study summarizes the articles available on the scientific and electronic databases Embase, Medline, and Scopus until the end of 2017, including case studies describing beneficial microbes as tools for improving the process of controlling infectious diseases. Until the development of novel vaccines or other approaches occurs, the use of probiotics seems to be a logical way to attempt to control certain infectious diseases.  相似文献   
73.
AIM: To compare the anterior segment measurements obtained by rotating Scheimpflug camera (Pentacam) and Scanning-slit topography (Orbscan IIz) in keratoconic eyes. METHODS: A total of 121 patients, 71 males (58.7%) and 50 females (41.3%) (214 eyes) with the diagnosis of keratoconus (KC) were enrolled in this study. Following diagnosis of KC by slit-lamp biomicroscopic examination, central corneal thickness (CCT), thinnest corneal thickness (TCT), anterior chamber depth (ACD), and pupil diameter (PD) were measured by a single examiner using successive instrumentation by Pentacam and Orbscan. RESULTS: There was no significant difference between the two instruments for the measurement of CCT and TCT. In contrast, scanning-slit topography measured ACD (3.46±0.40 mm vs. 3.38±0.33 mm, P=0.019) and PD (4.97±1.26 mm vs 4.08±1.19 mm, P<0.001) significantly larger than rotating Scheimpflug camera. The two devices made similar measurements for CCT (95% CI: -2.94 to 5.06, P=0.602). However, the mean difference for TCT was -6.28 (95% CI: -10.51 to -2.06, P=0.004) showing a thinner measurement by Orbscan than by Pentacam. In terms of the ACD, the mean difference was 0.08 mm (95% CI: 0.04 to 0.12, P<0.001) with Orbscan giving a slightly larger value than Pentacam. Similarly, Orbscan measurement for PD was longer than Pentacam (95% CI: 0.68 to 1.08, P<0.001). CONCLUSION: A good agreement was found between Pentacam and Orbscan concerning CCT measurement while comparing scanning-slit topography and rotating Scheimpflug camera there was an underestimation for TCT and overestimation for ACD and PD.  相似文献   
74.

Objective

Overweight among adolescents is not only an important public health problem but also a problem affecting economic growth in developing countries. The aim of this study was to investigate the parental determinants of overweight and obesity in Iranian adolescents at national level.

Methods

This cross sectional study was conducted within the framework of the Comprehensive Study on Household Food Consumption Patterns and Nutritional Status of IR Iran during 2001-2003. In adolescents, anthropometric indices were defined based on the CDC 2000 cut-off points for age and gender-specific body mass index (BMI). Parental characteristics were collected by questionnaire. Among the 7158 participating households, data on 7908 adolescents aged 11-19 years (3750 girls and 4158 boys) was analyzed.

Findings

The prevalence of overweight (85–94th percentile) in boys and girls was 6.2%, and 8.7%, respectively. The prevalence of obesity (≥95th percentile) among boys and girls was similar (3.3%). Parents’ weight status, father''s job and parents’ education showed significant association with weight status in adolescents. Logistic regression analysis showed that parental overweight and obesity, parental education and father''s job were the main parental determinants of overweight and obesity in Iranian adolescents.

Conclusion

Parental overweight and obesity, parental education and father''s job seem to be the major parental determinants of overweight in Iranian adolescents. Future prevention programs must take these risk factors into account.  相似文献   
75.

Background  

Bacterial endophthalmitis is a serious complication of penetrating ocular trauma and cataract surgery. The purpose of this study is to assess the ability of an anterior chamber air bubble to prevent experimental Staphylococcus epidermidis endophthalmitis.  相似文献   
76.

Objective

We evaluated the efficacy of topical application of the injectable form of tranexamic acid (TXA) compared with anterior nasal packing (ANP) for the treatment of epistaxis in patients taking antiplatelet drugs (aspirin, clopidogrel, or both) who presented to the emergency department (ED).

Methods

A randomized, parallel‐group clinical trial was conducted at two EDs. A total of 124 participants were randomized to receive topical TXA (500 mg in 5 mL) or ANP, 62 patients per group. The primary outcome was the proportion of patients in each group whose bleeding had stopped at 10 minutes. Secondary outcomes were the rebleeding rate at 24 hours and 1 week, ED length of stay (LOS), and patient satisfaction.

Results

Within 10 minutes of treatment, bleeding was stopped in 73% of the patients in the TXA group, compared with 29% in the ANP group (difference = 44%, 95% confidence interval, 26% to 57%; p < 0.001). Additionally, rebleeding was reported in 5 and 10% of patients during the first 24 hours in the TXA and the ANP groups, respectively. At 1 week, 5% of patients in the TXA group and 21% of patients in the ANP group had experienced recurrent bleeding (p = 0.007). Patients in the TXA group reported higher satisfaction scores (median [interquartile range {IQR}], 9 [8–9.25]) compared with the ANP group (median [IQR] = 4 [3–5]; p < 0.001). Discharge from the ED in <2 hours was achieved in 97% of patients in the TXA group versus 13% in the ANP group (p < 0.001). There were no adverse events reported in either group.

Conclusions

In our study population, epistaxis treatment with topical application of TXA resulted in faster bleeding cessation, less rebleeding at 1 week, shorter ED LOS, and higher patient satisfaction compared with ANP.  相似文献   
77.
Abstract: The effects of different doses of lithium (5-320 mg/kg intramuscularly) and rubidium (0.25-32 mg/kg intramuscularly) on apomorphine-induced pecking were investigated in pigeons. These two cations did not induce pecking by itself. Intramuscular administration of apomorphine (a mixed D1/D2 dopamine receptors agonist, 0.1-1.6 mg/kg) induced pecking in a dose-dependent manner. SCH 23390 (Dl dopamine receptor antagonist, 0.02-0.08 mg/kg) and sulpiride (D2 dopamine receptor antagonist, 25-100 mg/kg) decreased apomorphine-induced pecking dose-dependently. Combination of SCH 23390 (0.04 mg/kg) with sulpiride (50 mg/kg) caused a stronger inhibitory effect on apomorphine response. This indicates that both Dl and D2 dopamine receptors are involved in apomorphine-induced pecking. The response induced by apomorphine (0.2-0.8 mg/kg) was decreased in animals pretreated with lithium and rubidium. In these conditions, SCH 23390 and sulpiride produced a larger inhibitory effect on the apomorphine response, suggesting that acute lithium and rubidium pretreatment inhibit pecking by interfering with dopaminergic mechanisms.  相似文献   
78.
ABSTRACT

This study reports on the characteristics, sources, and health risks of atmospheric PM10-bound heavy metals (HMs) on citizenship living in different regions of Ahvaz, Southwest of Iran were investigated during 2016–2017. A total of 84 samples were analyzed from different regions: (S1) industrial, (S2) high traffic, and (S3) residential. Blood samples were collected from people who came to the east health center of Ahvaz. High volume air samplers, equipped with quartz fiber filters (8?×?10) were utilized for sampling in this study. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was also used for HMs. Risk assessment and hazard index of these pollutants were estimated, using USEPA’s exposure parameters. Based on the results, the highest and the lowest concentration of HM were observed in industrial and residential areas. Blood’s HMs concentration for chromium (Cr), nickel (Ni), lead (Pb), and zinc (Zn) were 2.932, 4.199, 8.425, and 71.2?μg/dL, respectively. In conclusion, increasing exposure concentration of HMs would have a significant potential for increased cancer and risk of diseases. The results of this study show that increasing exposure concentration to HM in the studied scenarios have a significant potential for generating different health endpoints, although exposing to HMs led to generating diseases in individuals particularly in polluted and populated districts; so, environmental measures should be considered by urban air authorities to mitigate the concentration of these pollutants in ambient air.  相似文献   
79.
80.
Objectives: One-third of epileptic patients are resistant to antiepileptic drugs. Few clinical studies with small sample size indicate that polyunsaturated fatty acids could control drug-resistant epilepsy. We examined the efficacy of acute and chronic administration of docosahexaenoic acid (DHA) in two animal models of drug-resistant epilepsies, i.e. 6-Hz psychomotor seizures in mice and lamotrigine (LTG)-resistant kindled rats.

Methods: Mice received a single injection of DHA (300?µM, i.c.v.) along with phenytoin (PHT) or LTG (i.p.). Six-Hz electroshock (0.2?milliseconds rectangular pulse width, 3?seconds duration, 44?mA current) was given 15 minutes after DHA, and seizure behaviors were recorded. In LTG-resistant kindled rats, a single dose of DHA (300?µM, i.c.v.) was administered with LTG, and seizure parameters were measured. In chronic treatment, mice received DHA (0.1?g/day, orally) for 30 days. Then, a single dose of LTG or PHT was administered to mice and 6-Hz-induced seizures were recorded. In rats, DHA (1?µM, i.c.v.) was administered during kindling development and effect of LTG in DHA-pretreated LTG-resistant kindled rats was verified.

Results: LTG and PHT did not inhibit 6-Hz seizures in mice after single injection of DHA. However, LTG and PHT inhibited 6-Hz seizures in mice that received DHA for 1?month. Acute or chronic administration of DHA to LTG-resistant kindled rats led to the suppression of kindled seizure parameters by LTG.

Discussion: DHA removes the ‘inherent resistance’ of 6-Hz seizures to PHT and LTG, and prevents the development of pharmacodynamic tolerance to LTG in LTG-resistant kindled rats. DHA might have potential to be used as add-on therapy in patients with refractory epilepsy.  相似文献   
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