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91.
92.
In addition to the effect that the COVID-19 pandemic has had on the physical and mental health of individuals, it has also led to a change in the mental and emotional state of many employees. Especially among businesses and private companies, which faced many restrictions due to the special conditions of the pandemic. Therefore, the present study aimed to design an artificial neural network with MLP technique to analyze the relationship between demographic variables, resilience, COVID-19 and burnout in start-ups in Iran. The research method was quantitative. Managers and employees of start-ups formed the statistical population of the study, based on the statistical sample size of the unlimited community, 384 of them were tested. For data gathering, standard questionnaires include of MBI-GS and BRCS and researcher-made questionnaire of stress caused by COVID-19 were used. The validity of the questionnaires was confirmed by a panel of experts and their reliability was confirmed by Cronbach’s alpha coefficient. The number of neurons in the input layer was equal to 10, the number of neurons in the 1st hidden layer was equal to 7, the number of neurons in the output layer was equal to 1, and the number of epochs was equal to 500. 70% of the data were used for training and 30% for testing. In the designed artificial neural network, all experiment data except one were correctly predicted and the obtained MAE error was less than 0.012%. Finally, he precision and correction of the presented model was confirmed by the obtained results.  相似文献   
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Purpose

A prospective observational study is conducted to identify independent predictors of pain and morphine consumption following abdominal hysterectomy.

Methods

Preoperative State Trait Anxiety Inventory (STAI), Numerical Rating Scales (NRS) for anxiety and pain expectations, thermal pain thresholds and pain scores at forearm and incision site, and pain scores generated from the insertion of an intravenous catheter were measured in female patients undergoing abdominal hysterectomy. Pearson correlations between the predictors and the two outcome measures postoperative pain scores and morphine consumption were studied and multiple regression analysis was conducted to identify independent predictors (primary outcome). Secondary outcomes included cut-off values of predictive tools for morphine consumption.

Results

Data from 60 patients were analyzed. STAI state anxiety, NRS pain expectations, and NRS anxiety scores were identified as independent predictors of postoperative morphine consumption. We identified a cut-off value of 4.5 (sensitivity 90 %, specificity of 60 %) for the NRS anxiety and a cut-off of 42.5 (sensitivity 70 %, specificity 70 %) for the state anxiety STAI score for increased postoperative morphine consumption.

Conclusions

Preoperative STAI state anxiety scores and NRS pain expectations are independent predictors for increased morphine consumption following hysterectomy. The STAI state anxiety tool and NRS 0-10 anxiety tool can be used interchangeably. The NRS 0-10 anxiety is a much simpler tool than STAI state anxiety and is associated with a higher sensitivity for high morphine consumption. Thermal pain thresholds and IV pain scores were not predictive of postoperative morphine consumption.
  相似文献   
95.
The effects of alexandrite laser (AL) on skin parameters such as melanin content, skin layer depth, elasticity, and density have not been investigated through biometric methods. We aim to assess the effect of AL on the skin parameters through biometric devices to determine whether it has positive effects on treated region. In this pretest-posttest study, we recruited patients who attended Laser Clinic of Skin and Stem Cell Research Center, Tehran University of Medical Sciences, Tehran, Iran, from January through December 2014. Patients had to be free of any dermatologic conditions and lesion at the site of treatment or any contraindication to laser therapy. Baseline measurements were performed and patients received four sessions of AL therapy (spot size, 12 mm; fluence, 12 J/cm2; and pulse width, 5 Hz) with 4-week intervals. Four weeks after the last treatment session, the same parameters were assessed that included skin color, transepidermal water loss (TEWL), dermis and epidermis density and depth (through skin ultrasonography), melanin content, erythema intensity, and skin elasticity. Biometric parameters of 33 patients (27 females [81.8 %]), with mean (SD) age of 35.7 (9.5)?years were evaluated. The mean percent changes of skin parameters were as follows: skin color, 5.88 % through Visioface and by 56.8 % through Colorimeter devices (became lighter); melanin content, ?15.95 %; TEWL, ?2.96 %; elasticity, +14.88 %; dermis depth ?19.01 %; and dermis density, +1580.11 % (P?<?0.001 for changes in each parameter). AL could decrease melanin content of the skin and make the skin thinner while it could increase elasticity and density of epidermis and dermis, which might indicate increased collagen content of skin.  相似文献   
96.

Purpose

Local tumor ablation (LTA) and partial nephrectomy (PN) represent treatment alternatives for patients diagnosed with small renal mass and both may result in renal function detriments. The aim of the study was to compare renal function detriments after LTA or PN.

Methods

A Surveillance epidemiology and End Results-Medicare-linked retrospective cohort of 2850 T1 kidney cancer patients who underwent LTA or PN was abstracted. Short-term outcomes consisted of 30-day acute kidney injury (AKI) and 30-day dialysis rates. Long-term outcomes consisted of episodes of AKI, mild and moderate–severe chronic kidney disease (CKD), end-stage renal disease, hemodialysis and anemia in CKD. Analyses consisted of propensity score matching, logistic and Cox regression.

Results

After propensity score matching, 1122 patients remained. The 30-day incidence of AKI was 4.6 % after LTA and 9.4 % after PN. In multivariable analyses (MVAs), LTA was associated with a lower AKI rate (OR 0.42; p = 0.001). The 30-day incidence of any dialysis was <2 % after either LTA or PN. In MVA, LTA was not associated with a lower rate of any dialysis (OR 0.43; p = 0.2). At long-term assessment, both the unadjusted and adjusted rates of all six examined end points were not different between LTA and PN (all p > 0.5).

Conclusions

LTA offers short-term protective effect from AKI. The short-term rates of any dialysis treatment are similar after either LTA or PN. At long-term assessment, LTA and PN renal function detriment rates are not different. Concern for long-term functional outcomes should not be a barrier for PN.
  相似文献   
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Premature ovarian insufficiency (POI) affects approximately 1% of women before the age of 40. Genetic contribution is a significant component of POI. In this context, heterozygous mutations in NOBOX, BMP15 and GDF9 have been reported. The objective of our study was to evaluate the prevalence of these genes mutations in 125 unrelated Tunisian patients diagnosed with POI. The screening of NOBOX gene revealed three missense mutations (p.Arg117Trp; p.Gly91Trp and p.Pro619Leu) in eight patients. These mutations were not found in a 200 ethnically matched women without fertility problem. The sequencing of BMP15 and GDF9 gene revealed only previously reported variants. In contrast to previous studies, the prevalence of BMP15 variations is not higher than in the control population. Conversely, 6.4% of the cases present a NOBOX mutations; this high prevalence strengthens the consideration of NOBOX gene as strong autosomal candidate for POI.  相似文献   
100.
The purpose of this study was to examine the effects of different resolution and noise levels on task performance in digital mammography. This study created an image set with images at three different resolution levels, corresponding to three digital display devices, and three different noise levels, with noise magnitudes similar to full clinical dose, half clinical dose, and quarter clinical dose. The images were read by five experienced breast imaging radiologists. The data were then analyzed to compute two accuracy statistics (overall classification accuracy and lesion detection accuracy) and performance at four diagnostic tasks (detection of microcalcifications, benign masses, malignant masses, and discrimination of benign and malignant masses). Human observer results showed decreasing display resolution had little effect on overall classification accuracy and individual diagnostic task performance, but increasing noise caused overall classification accuracy to decrease by a statistically significant 21% as the breast dose went to one quarter of its normal clinical value. The noise effects were most prominent for the tasks of microcalcification detection and mass discrimination. When the noise changed from full clinical dose to quarter clinical dose, the microcalcification detection performance fell from 89% to 67% and the mass discrimination performance decreased from 93% to 79%, while malignant mass detection performance remained relatively constant with values of 88% and 84%, respectively. As a secondary aim, the image set was also analyzed by two observer models to examine whether their performance was similar to humans. Observer models differed from human observers and each other in their sensitivity to resolution degradation and noise. The primary conclusions of this study suggest that quantum noise appears to be the dominant image quality factor in digital mammography, affecting radiologist performance much more profoundly than display resolution.  相似文献   
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