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1.
Mina Saeedneja Mohammadreza Zafarghandi Narjes Khalili Vali Baigi Moein Khormali Zahra Ghodsi Mahdi Sharif-Alhoseini Gerard M. O’Reilly Khatereh Naghdi Melika Khaleghi-Nekou Seyed mohammad Piri Vafa Rahimi-Movaghar Somayeh Bahrami Marjan Laal Mahdi Mohammadzadeh Esmaeil Fakharian Habibollah Pirneja Hamid Pahlavanhosseini Payman Salamati Homayoun Sadeghi-Bazargani 《中华创伤杂志(英文版)》2021,24(3):153-158
Purpose: Injuries are one of the leading causes of death and lead to a high social and financial burden. Injury patterns can vary significantly among different age groups and body regions. This study aimed to evaluate the relationship between mechanism of injury, patient comorbidities and severity of injuries.
Methods: The study included trauma patients from July 2016 to June 2018, who were admitted to Sina Hospital, Tehran, Iran. The inclusion criteria were all injured patients who had at least one of the following: hospital length of stay more than 24 h, death in hospital, and transfer from the intensive care unit of another hospital. Data collection was performed using the National Trauma Registry of Iran minimum dataset.
Results: The most common injury mechanism was road traffic injuries (49.0%), followed by falls (25.5%). The mean age of those who fell was significantly higher in comparison with other mechanisms (p < 0.001). Severe extremity injuries occurred more often in the fall group than in the vehicle collision group (69.0% vs. 43.5%, p < 0.001). Moreover, cases of severe multiple trauma were higher amongst vehicle collisions than injuries caused by falls (27.8% vs. 12.9%, p = 0.003).
Conclusion: Comparing falls with motor vehicle collisions, patients who fell were older and sustained more extremity injuries. Patients injured by motor vehicle collision were more likely to have sustained multiple trauma than those presenting with falls. Recognition of the relationship between mechanisms and consequences of injuries may lead to more effective interventions. 相似文献
2.
Paul D. Righi Deepkaran K. Reddy Edward C. Weisberger Matthew S. Johnson Scott O. Trerotola Shokri Radpour Paul E. Johnson Christopher E. Stevens 《The Laryngoscope》1998,108(7):1020-1024
Objective: The establishment of a direct enteral feeding route is critical in the overall treatment of many patients with head and neck cancer. Use of radiologic percutaneous gastrostomy (RPG), the newest technique for gaining enteral access, has not been studied in such patients extensively. This study evaluated the indications, technique, success rate, and complications associated with RPG in patients with head and neck cancer. Study Design: Retrospective. Methods: A comprehensive chart review was undertaken of 56 patients with head and neck cancer treated at a tertiary care institution who had undergone successful or attempted RPG at some point during their treatment course. Results: Most study patients had advanced oropharyngeal squamous cell carcinoma. The most frequent indications for RPG were dysphagia/aspiration following tumor resection (n = 26) and dysphagia following completion of single- or combined-modality therapy (n = 22). The success rate of attempted RPGs was 98.2%. The overall complication rate for RPG was 12.7% (10.9% minor and 1.8% major). Conclusions: RPG is a valuable tool for establishing enteral nutrition in patients with head and neck cancer. Advantages of RPG include high success rate despite obstructing lesions, low complication rate, time efficiency and scheduling ease compared with intraoperative percutaneous gastrostomy (PEG) by a second team, no reported tumor seeding of the tube site, and the fact that postoperative RPG allows for more accurate selection of patients who require a gastrostomy tube. 相似文献
3.
4.
Congenital aortocaval fistula between right aortic sinus of Valsalva and superior vena cava: A rare case report 下载免费PDF全文
Mozhdeh Dabirian MD Ali Ghaemian MD Maryam Nabati MD Samad Golshani MD Mojtaba Shokri MD 《Echocardiography (Mount Kisco, N.Y.)》2018,35(3):413-416
Thoracic aortocaval fistula is a very rare cause of left to right shunt. Drainage of fistula into the superior vena cava (SVC) is very uncommon. Clinical symptoms depend on the size of the shunt. We report a rare case of an asymptomatic 27‐year‐old woman with congenital aortocaval fistula to the SVC with a small amount of left to right shunt that was considered for serial medical follow‐up. 相似文献
5.
Amirhossein Hassani Adisa Azapagic Nima Shokri 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(52):33017
Knowledge of spatiotemporal distribution and likelihood of (re)occurrence of salt-affected soils is crucial to our understanding of land degradation and for planning effective remediation strategies in face of future climatic uncertainties. However, conventional methods used for tracking the variability of soil salinity/sodicity are extensively localized, making predictions on a global scale difficult. Here, we employ machine-learning techniques and a comprehensive set of climatic, topographic, soil, and remote sensing data to develop models capable of making predictions of soil salinity (expressed as electrical conductivity of saturated soil extract) and sodicity (measured as soil exchangeable sodium percentage) at different longitudes, latitudes, soil depths, and time periods. Using these predictive models, we provide a global-scale quantitative and gridded dataset characterizing different spatiotemporal facets of soil salinity and sodicity variability over the past four decades at a ∼1-km resolution. Analysis of this dataset reveals that a soil area of 11.73 Mkm2 located in nonfrigid zones has been salt-affected with a frequency of reoccurrence in at least three-fourths of the years between 1980 and 2018, with 0.16 Mkm2 of this area being croplands. Although the net changes in soil salinity/sodicity and the total area of salt-affected soils have been geographically highly variable, the continents with the highest salt-affected areas are Asia (particularly China, Kazakhstan, and Iran), Africa, and Australia. The proposed method can also be applied for quantifying the spatiotemporal variability of other dynamic soil properties, such as soil nutrients, organic carbon content, and pH.Soil salinization is one of the main land-degrading threats influencing soil fertility, stability, and biodiversity. Saline soils are ones with excess accumulation of soluble salts in the root zone (1). On the other hand, accumulation of high levels of sodium salt relative to other exchangeable cations is the main attribute of sodic soils (2). Wind, rainfall, and parent rock weathering are the main origins of these salts in “primary” soil salinization, whereas in “secondary” soil salinization excessive salt accumulation is human-induced (3). Saline and sodic soils, or in general salt-affected soils, mostly lie across arid and semiarid climates where the dominance of evaporation over precipitation concentrates the salts in the root zone (1, 4), leading to undesirable alterations in the physical, chemical, and biological functions of the soil (5, 6). Sodicity adversely influences the soil infiltration capacity (7), increases the susceptibility of water and wind-blown erosion (8), and exposes more soil organic matter to decomposing processes (9). Soil salinity, on the other side, distresses the soil respiration, nitrogen cycle, and decomposing functionality of soil microorganisms (9, 10). Salinity stress affects the vegetation growth directly by reducing the plant water uptake (osmotic stress) and/or by deteriorating the transpiring leaves (specific ion effects) (11), in turn reducing organic input to the soil and ultimately leading to desertification of lands (12, 13). Under extreme conditions, dispersion of saline dust (8, 14), poverty, migration, and high costs of soil reclamation are long-term socioeconomic consequences of soil salinization (15).Soil salinity and sodicity levels are spatially, vertically, and temporally dynamic (15, 16), particularly at the top 0- to 30-cm soil layer which is substantially affected by governing climatic conditions. Naturally occurring events, such as flash floods, El Niño and La Niña, alternative wet and dry years, and long periods of drought can considerably affect soil salinization and accumulation/leaching of the salts in/from the root zone at daily to multiyear temporal resolutions. Similarly, anthropogenic activities like irrigation and dryland management can affect soil salinization at different temporal resolutions. Given the high dynamism in soil salinization processes, updated spatial and temporal information on the extent of salt-affected soils is indispensable for devising appropriate sustainable action programs for managing land and soil resources (6, 17–19). This information can be also valuable for enhancing our understanding of terrestrial carbon dynamics (7, 20), food security and agricultural modeling (21, 22), climate change impacts (23, 24), water resources and irrigation management (25, 26), and efficiency of organic/inorganic reclamation practices (27, 28). Several statistics on the global distribution of salt-affected soils (17–19, 29–33) have been generated based on data from soil surveys and statistical extrapolation (1, 19), yet these estimations are mainly purely spatial (17, 34), not necessarily up-to-date (15, 17), and in some cases incomparable (3, 35). Therefore, there is still a need for a methodologically consistent dataset documenting long-term variations of the soil salinity and sodicity at high spatial resolutions (36)To address this need, we focused on two target variables: ground-derived measurements of soil ECe (the ability of a water-saturated soil paste extract to conduct electrical current, representative of salinity severity) and ESP (exchangeable sodium percentage, representative of sodicity severity). We used 42,984 and 197,988 data, respectively, scattered over time from 1980 to 2018. We trained two-part predictive models for making four-dimensional (4D) predictions of soil salinity and sodicity as target variables (longitude, latitude, soil depth, and time; see Methods). Through mapping data-driven relations between soil ECe/ESP observations and a collection of associated predictors generated from topographic, climatic, vegetative, soil, and landscape properties of the sampling locations (SI Appendix, Table S1), these two-part models enabled us to make long-term gridded predictions of soil salinity and sodicity at new locations with available predictors’ values. Note that “prediction” refers to the estimation by the trained models of soil salinity/sodicity on a global scale from 1980 to 2018 even in locations where there is no measurement available rather than to future projection of soil salinity/sodicity on the basis of current trends. The first part of the models classified the soil into saline/sodic and nonsaline/nonsodic classes (binary classification) and the second part predicted per-class severity of the salinity/sodicity issue (regression). Meaningful statistics derived from the ECe and ESP predictions were then used to generate univariate thematic maps of the variability of different aspects of soil salinity/sodicity between 1980 and 2018 at ∼1-km spatial resolution (30 arc-seconds; e.g., Fig. 1). These were delimited to −55° and 55° latitudes, comprising tropics, subtropics, and temperate zones (see Data Availability). We focused on the topsoil layer (or surface soil), referring to the top 30 cm of the soil profile measured from the surface.Open in a separate windowFig. 1.Variability of different aspects of soil salinity and sodicity in the western United States. (A and D) SD of annually predicted soil salinity (ECe) and sodicity (ESP), respectively, between 1980 and 2018. (B and E) Average of annually predicted ECe and ESP, respectively (1980 to 2018). (C and F) Change in the likelihood (θ) of soils with an ECe ≥4 dS⋅m−1 or ESP ≥6% in the period 2000 to 2018 relative to 1981 to 1999 (the likelihood is dimensionelss, calculated by dividing the number of years with ECe ≥4 dSm−1 or ESP ≥6% by the total number of years in the studied period). Positive θ indicates that the likelihood has increased and negative shows that it has decreased. 相似文献
6.
Esmaeil Idani Sahar Geravandi Morteza Akhzari Gholamreza Goudarzi Nadali Alavi Ahmad Reza Yari 《Toxin reviews》2020,39(3):266-274
ABSTRACTThis 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
7.
Esmaeil Biazar Alireza Baradaran-Rafii Saeed Heidari-keshel Sara Tavakolifard 《Journal of biomaterials science. Polymer edition》2013,24(16):1139-1151
The aim of this study was to develop nanofibrous silk substrates for limbal stem cell expansion that can serve as a potential alternative substrate to replace human amniotic membrane. The human limbal stem cell was used to evaluate the biocompatibility of substrates (random and oriented nanofibrous mats, and human amniotic membrane) based on their phenotypic profile, viability, proliferation, and attachment ability. Biocompatibility results indicated that all substrates were highly biocompatible, as limbal stem cells could favorably attach and proliferate on the nanofibrous surfaces. Microscopic figures showed that the human limbal stem cells were firmly anchored to the substrates and were able to retain a normal corneal stem cell phenotype. Microscopic analyses illustrated that cells infiltrated the nanofibers and successfully formed a three-dimensional corneal epithelium, which was viable for 15 days. Immunocytochemistry and real-time PCR results revealed no change in the expression profile of limbal stem cells grown on nanofibrous substrates when compared to those grown on human amniotic membrane. In addition, electrospun nanofibrous silk substrates especially oriented mat provides not only a milieu supporting limbal stem cells expansion, but also serve as a useful alternative carrier for ocular surface tissue engineering and could be used as an alternative substrate to amniotic membrane. 相似文献
8.
Melatonin protects testes against lithium‐pilocarpine‐induced temporal lobe epilepsy in rats: a time course study 下载免费PDF全文
S. Shokri M. Kazemi M. A. Firouzjaei M. Hemadi A. Moayeri M. Ganjkhani R. Nejatbakhsh 《Andrologia》2015,47(3):343-353
Male dysfunction is common in patients with temporal lobe epilepsy (TLE). We evaluated whether melatonin, as a supplement, can play a positive role in reducing the epileptogenesis imposing abnormalities of spermatozoa and testes in epileptic rats. Status epilepticus was induced based on the TLE lithium‐pilocarpine model. Two patterns of melatonin were administered to the epileptic animals along the mean durations of latent (14 days) and chronic (60 days) phases. Sperm parameters, different antioxidant enzyme levels, germ cell apoptosis, body and relative sex organ weights were evaluated in all groups 60 days following SE induction. Chronic TLE caused a significant reduction in sperm parameters. In the testis, the reduced level of antioxidant enzymes was accompanied by a significant increase in malondialdehyde concentration. The presence of oxidant condition in the testes of epileptic animals caused expanded apoptosis in the germ cell layer. Moreover, the amount of weight gain in epileptic animals was more prominent. Melatonin administration was able to improve sperm motility by increasing the total antioxidant level. There was also a significant reduction in the spermatogenic cell line apoptosis and the extra weight gain of melatonin‐treated animals. Melatonin supplementation might be considered as an acceptable cotreatment in epileptic patients. 相似文献
9.
BACKGROUND AND OBJECTIVES: Despite a successful outcome of the anti-D prophylaxis programme, alloimmunization still occurs. The aim of this study was to estimate the frequency of Rh-specific B lymphocytes in the peripheral blood of nine Rh-alloimmunized individuals at different time intervals after parturition. MATERIALS AND METHODS: The donors' B lymphocytes were transformed with Epstein-Barr virus (EBV) and cultured at different cell densities over a feeder of human fetal fibroblasts. Culture supernatants were screened for human immunoglobulin by enzyme-linked immunosorbent assay (ELISA) and for anti-Rh antibody by using a direct haemagglutination technique. The percentage of CD19+ B lymphocytes in peripheral blood was determined by flow cytometry, and the frequency of Rh-specific B lymphocytes was estimated by limiting-dilution assay (LDA). RESULTS: The frequency of Rh-specific B lymphocytes varied from 1 : 150 to 1 : 27,850 in different donors. There was a decrease in this frequency and level of anti-Rh antibody with increase in time interval between bleeding and last exposure to the antigen. Furthermore, a positive correlation was observed between the titre of Rh-specific antibody and frequency of Rh-specific B cells in each of three subjects bled at multiple time-points postdelivery. CONCLUSIONS: The magnitude of the specific antibody response to Rh antigens varies greatly in Rh-alloimmunized women, which partly reflects the difference in frequency of specific B cells in these individuals. 相似文献
10.
Negin Badihian Roya Riahi Mostafa Qorbani Mohammad Esmaeil Motlagh Ramin Heshmat Roya Kelishadi 《Journal of clinical hypertension (Greenwich, Conn.)》2020,22(8):1434-1441
Although blood pressure (BP) tracks from childhood to adulthood, and the prevalence of pediatric primary hypertension is increasing, related determinants are not well understood. The role of noise pollution and psychological distress in increasing BP is well documented in adults, but it remains elusive in children. This study aims to investigate the association of noise annoyance and psychological distress with BP in a pediatric population. This national cross‐sectional study was conducted in 2015 on a sample of 14400 Iranian students, aged 7‐18 years. Information regarding noise annoyance and psychological distress were assessed using questionnaires, and BP values were measured. Levels of noise annoyance and psychological distress were classified based on tertiles to no/low, moderate, and high. Data of 14274 students were completed. The mean age of participants was 12.28 (0.05), with 51% boys and 71.4% urban inhabitant. Diastolic BP and mean arterial BP (MAP) had positive correlations with noise annoyance (regression coefficient: 0.028, 95 % CI: 0.005 ‐ 0.05 and 0.025, 95 % CI: 0.002 – 0.04, respectively). Participants with higher psychological distress were 15 % more likely to experience abnormally high BP compared to those with normal psychological status or mild distresses (OR: 1.15, 95 % CI: 1.003 – 1.34). Here, we found significant positive relationships between the level of noise annoyance and values of diastolic BP and MAP. Moreover, high psychological distress showed to increase the chance of abnormally high BP. The clinical impact of these findings should be assessed in further longitudinal studies. 相似文献