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BackgroundWork-related musculoskeletal injuries have been increasingly recognized to affect surgeons. It is unknown whether such injuries also affect surgical trainees. The purpose of this study was to assess the ergonomic risk of surgical trainees as compared with that of experienced surgeons.MethodsErgonomic data were recorded from 9 surgeons and 11 trainees. Biomechanical loads during surgery were assessed using motion tracking sensors and electromyography sensors. Demanding and static positions of the trunk, neck, right/left shoulder, as well as activity from the deltoid and trapezius muscles bilaterally were recorded. In addition, participants reported their perceived discomfort on validated questionnaires.ResultsA total of 87 laparoscopic general surgery cases (48 attendings and 39 trainees) were observed. Both trainees and attendings spent a similarly high percentage of each case in static (>60%) and demanding positions (>5%). Even though residents reported overall more discomfort, all participants shared similar ergonomic risk with the exception of trainees’ trunk being more static (odds ratio: –11.42, P = .006).ConclusionSurgeons are prone to ergonomic risk. Trainees are exposed to similar postural ergonomic risk as surgeons but report more discomfort and, given that musculoskeletal injuries are cumulative over time, the focus should be on interventions to reduce ergonomic risk in the operating room.  相似文献   
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Convulsive seizures are due to abnormal synchronous and repetitive neuronal discharges in the central nervous system (CNS). Finding new therapeutics to overcome the side effects of the current drug therapies and to increase their effectiveness is ongoing. Orexin‐A and orexin‐B are brain neuropeptides originating from postero‐lateral hypothalamic neurons. Studies show that orexins, through activation of OX1 and OX2 receptors, have excitatory effects in the CNS. Accordingly, this study was designed to evaluate the effect of OX1 receptor antagonist (SB‐334867) on seizure‐ and anxiety‐related behaviors of pentylenetetrazol (PTZ)‐kindled rats. Kindling was induced by repeated intraperitoneal (IP) injections of PTZ (32 mg/kg) with two‐day intervals for 24 days in male Wistar rats. Three groups received intracerebroventricular (ICV) injections of SB‐334867 (2.5, 5, and 10 μg/rat) before PTZ injections. Two control groups received vehicle (2 μL/rat, ICV) and valproate (26 μg/rat, ICV) before PTZ injections. An extra group of control animals received saline both ICV and IP. Seizure‐related behaviors were monitored for 30 min following PTZ administration. The anxiety‐like behaviors were also assessed using elevated plus‐maze in the first and last days of the study. The results revealed that ICV injection of SB‐334867, mainly at the dose of 10 μg/rat, decreased the median of seizure stages, prolonged the latency and reduced the duration of different seizure stages, and reversed the PTZ‐induced anxiety‐like behaviors. Based on the presented results, it is suggested that pharmacological blockade of the OX1 receptor is a potential target in the treatment of seizure and concomitant anxiety disorders.  相似文献   
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For this investigation, 28 female healthy adult Wistar rats were selected. The animals were divided into four groups (n?=?7 per group): control, test group 1, test group 2 and test group 3. Each rat in test groups 1, 2 and 3, received 0.8 ppm, 1.6 ppm and 3.2 ppm aflatoxin B1 (AFB1), respectively, via gavage for a period of 25 days. The control group received distilled water only. All tissue specimens were processed for routine paraffin embedding and serial cross-sections cut at 5–7 μm and stained with haematoxylin–eosin. Both histomorphologic and histomorphometric analysis was performed under light microscopy. An increase in the concentration of AFB1 resulted in a reduction in the population of healthy primordial, primary, secondary and tertiary follicles. The greatest reduction was in seen in group 3 (with 3.2 ppm AFB1/day). In all test groups, due to an increase in AFB1 concentration, in both the right and left ovaries, all types of atretic follicles, including primordial, primary, secondary, and tertiary atretic follicles were significantly increased (P?<?0.01). In conclusion, AFB1 is toxic for all type of ovarian follicles, including non-growing and growing follicles and exerts an atretogenic effect on all types of ovarian follicles. The atretogenic effect of AFB1 is dose dependant. Due to its toxic effects (gametotoxicity), the resting pool of ovarian follicles (primordial follicles) decreases significantly. The ovulatory follicular population either decreases or is completely depleted.  相似文献   
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The purpose of this study was to use rating of perceived exertion (RPE) scale to evaluate popular bilateral plyometric exercise intensities. Fourteen physically active men (age 20.64 ± 1.4 years; height 176.93 ± 6.83 cm; weight 75.28 ± 11.1 kg) volunteered to participate in this study and performed a set of ten repetitions plyometric exercises to depth jump from 35 cm box, 35 cm box jump, depth jump from 60 cm box, 60 cm box jump, pike jump, tuck jump, and squat jump in a session with 5-min rest in between exercises. RPE was measured following the completion of each exercise using 0–10 Borg RPE scale. Data were analyzed using repeated measures ANOVA and the level of significant was set at p <0.05. The results indicated that squat jump was harder than other types of bilateral plyometric exercises such as 35 cm box jump, depth jump from 35 cm box, and tuck jump (p < 0.05). Moreover, the 35 cm box jump was easier than other plyometric exercises (p < 0.05). With regard to the results of this investigation, it can be recommended that athletes and strength and conditioning professionals use these findings to design plyometric training in their training schedule and keep in their mind that plyometric exercises have different intensities, however, the total volume was matched.  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   
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Objectives

Urinary tract infection caused by uropathogenic Escherichia coli (UPEC) strains is one of the most important infections in the world. UPEC encode widespread virulence factors closely related with pathogenesis of the bacteria. The purpose of this study was to evaluate the presence of different phenotypic virulence markers in UPEC isolates and determine their correlation with antibiotic resistance pattern.

Methods

UPEC isolates from patients with different clinical symptoms of UTI were collected and screened for biofilm and hemolysin production, mannose resistant, and mannose sensitive hemagglutination (MRHA and MSHA, respectively). In addition, antimicrobial resistance pattern and ESBL-producing isolates were recorded.

Results

Of the 156 UPEC isolates, biofilm and hemolysin formation was seen in 133 (85.3%) and 53 (34%) isolates, respectively. Moreover, 98 (62.8%) and 58 (37.2%) isolates showed the presence of Types 1 fimbriae (MSHA) and P fimbriae (MRHA), respectively. Our results also showed a relationship between biofilm formation in UPEC isolated from acute cystitis patients and recurrent UTI cases. Occurrence of UTI was dramatically correlated with the patients'' profiles. We observed that the difference in antimicrobial susceptibilities of the biofilm and nonbiofilm former isolates was statistically significant. The UPEC isolates showed the highest resistance to ampicillin, tetracycline, amoxicillin, and cotrimoxazole. Moreover, 26.9% of isolates were ESBL producers.

Conclusion

This study indicated that there is a relationship between the phenotypic virulence traits of the UPEC isolates, patients'' profiles, and antibiotic resistance. Detection of the phenotypic virulence factors could help to improve understanding of pathogenesis of UPEC isolates and better medical intervention.  相似文献   
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