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671.
Objective:Thoracic injuries are responsible for 25% of deaths of blunt traumas.Chest X-ray (CXR) is the first diagnostic method in patients with blunt trauma.The aim of this study was to detect the accuracy of CXR versus chest computed tomograpgy (CT) in hemodynamically stable patients with blunt chest trauma.Methods:Study was conducted at the emergency department of S ina Hospital from March 2011 to March 2012.Hemodynamically stable patients with at least 16 years of age who had blunt chest trauma were included.All patients underwent the same diagnostic protocol which consisted of physical examination,CXR and CT scan respectively.Results:Two hundreds patients (84% male and 16% female) were included with a mean age of(37.9±13.7) years.Rib fracture was the most common finding of CXR (12.5%) and CT scan (25.5%).The sensitivity of CXR for hemothorax,thoracolumbar vertebra fractures and rib fractures were 20%,49% and 49%,respectively.Pneumothorax,foreign body,emphysema,pulmonary contusion,liver hematoma and sternum fracture were not diagnosed with CXR alone.Conclusion:Applying CT scan as the first-line diagnostic modality in hemodynamically stable patients with blunt chest trauma can detect pathologies which may change management and outcome.  相似文献   
672.

Background

Leishmaniasis is a parasitic disease caused by different species of Leishmania parasites with a wide range of clinical manifestations. Antimonial compounds such as meglumine antimoniate (glucantime) are the first line drugs for the treatment of leishmaniasis. However, according to reports of the drug resistance of parasites, the efficacy of antimonial compounds is low. The ATP-binding cassette (ABC) proteins are present in all organisms and mediate the transport of vital elements through biological membranes. One of the important mechanisms of resistance in Leishmania parasites is the overexpression of ABC efflux pumps. P-glycoprotein A (pgpA) is a related gene for ABC transporter in Leishmania species. The aim of this study was to compare the pgpA expression in laboratory-induced resistant L. major (MRHO/IR/75/ER) and sensitive parasites.

Methods

RNA extraction of promastigotes of sensitive and resistant clones was performed and total RNA was reverse transcribed. The real-time quantitative polymerase chain reaction (PCR) was used to assess RNA expression profiles and the expression levels were calculated using 2-ΔCt method.

Results

The mean expression level of pgpA mRNA was 2.70 ± 0.51 in in sensitive Leishmania clone and 6.08 ± 1.50 in resistant Leishmania clone (P = 0.021).

Conclusion

The expression of pgpA gene in resistant strains of L. major was almost fivefold higher than those in susceptible strains. Therefore, this can be used in field isolates, i.e. overexpression of the gene can prove resistance in wild type field isolates.  相似文献   
673.

Aims

The aims of this study were to evaluate the effects of N-acetylcysteine (NAC) on cardiac remodeling and major adverse events following acute myocardial infarction (AMI).

Methods

In a prospective, double-blind, randomized clinical trial, the effect of NAC on the serum levels of cardiac biomarkers was compared with that of placebo in 98 patients with AMI. Also, the patients were followed up for a 1-year period for major adverse cardiac events (MACE), including the occurrence of recurrent myocardial infarction, death, and need for target vessel revascularization.

Results

In patients who received NAC, the serum levels of matrix metalloproteinase (MMP)-9 and MMP-2 after 72 h were significantly lower than those in the placebo group (p = 0.014 and p = 0.045, respectively). The length of hospitalization in patients who received NAC was significantly shorter than that in the placebo group (p = 0.024). With respect to MACE, there was a significant difference between those who received NAC (14 %) and those patients on placebo (25 %) (p = 0.024). Re-infarction took place in 4 % of patients in the NAC group as compared with 16.7 % in patients who received placebo (p = 0.007).

Conclusion

NAC can be beneficial in preventing early remodeling by reducing the level of MMP-2 and MMP-9. Moreover, NAC decreased the length of hospital stays in patients after AMI. By decreasing MACE, NAC could possibly be introduced as a ‘magic bullet’ in the pharmacotherapy of patients with AMI. Further studies are needed to elucidate NAC’s role in this population.  相似文献   
674.

Purpose

The aim was to culture primordial follicles in vitro to reach preantral stage in vitrified human ovarian tissue.

Methods

Ovarian tissue samples were obtained from six women. Tissue strips were vitrified by infiltration with a cryoprotectant followed by mounting on a stainless steel carrier. After culturing for 7 days the morphology and developmental stages of follicles enclosed in fresh and vitrified groups were analyzed.

Results

High proportion of viable follicles in vitrified ovarian strips was obtained. After culturing for 7 days the percentage of secondary and preantral follicles increased significantly (P < 0.05) whereas primordial and transitory follicles showed a significant decrease (P < 0.05) compared to their respective counterparts at day 0 of culture.

Conclusions

Vitrification of ovarian strips with an improved carrier device and culturing of follicles in ovarian strips after warming yielded developed follicles with high viability and morphological integrity that may be suitable for use in fertility preservation among cancer patients.  相似文献   
675.
Background: Trauma is the leading health concern among young adults. Blunt abdominal trauma (BAT) is the most common type of blunt traumas. BAT patients may prove normal in the initial clinical assessments, but since the time required for an intra-abdominal injury to be clinically apparent is not predictable, deciding when to safely discharge these patients could be a dilemma. The purpose of this study is to determine whether follow-up of the early discharged or further diagnostic assessment of the later discharged BAT patients with normal initial findings reveals any abnormal findings.

Methods: Totally, 389 hemodynamically-stable patients suspected of BAT who arrived at the emergency department (ED) of two university hospitals in Tehran from September 2013 to September 2014 were included in this study. Upon arrival at the ED, all subjects underwent abdominal examination and FAST, and were assessed for hematocrit and base deficit levels and presence of hematuria. These assessments were repeated in the patients who were discharged after 6?h, at 6 or 12?h post-arrival. All patients were followed-up after 24?h and one week by phone call.

Results: Out of all study participants, 158 patients (40.6%) had normal findings in all initial assessments. These patients were discharged from the ED after a median of 5?h. After one week of follow-up, none of them had any symptom or complication, or had sought medical attention after being discharged from the study hospitals. Out of these patients, 78 patients (49.4%) were discharged after 6?hours by their physician’s decision, and underwent the same diagnostic assessments for the second or third time. None of these assessments revealed any abnormal findings.

Conclusions: A combination of normal abdominal exam, normal FAST, normal hematocrit, normal base deficit, and absence of hematuria rules out intra-abdominal injury in BAT patients. It is safe to discharge patients after they prove normal for these assessments. Longer observation and repeated diagnostic assessment of these patients does not yield any new findings, and seems to be unnecessary.  相似文献   
676.
Background: Given the stressful nature of military life, people in the armed forces are vulnerable to substance use. Objectives: The aim of this study was to explore the relationship between family and peers with drug use among military forces in Iran. Methods: Convenience sampling was used to recruit a total of 422 draftees doing military service in army units in Tehran, Iran. Measures of family and peers' risk and protective factors, alcohol use, and other drug use were administered. Results: Findings indicated significant relationships between family (i.e., family models for risk behavior, parent sanctions, and family controls) and peers (i.e., peer modeling for risk behavior, peer controls, support from friends) with drug use. A multiple regression analysis revealed that peer modeling for risk behavior, family models for risk behavior, and parent sanctions were significant predictors of drug use in soldiers. Conclusions: These results were consistent with the influence of family and peer on drug use amongst soldiers. Programs designed to reduce alcohol and other drug use may benefit from tailoring to fit risk and protective files amongst peer and family networks.  相似文献   
677.
678.

Background

Existing permanent helical coil fasteners, although commonly employed for mesh fixation during laparoscopic hernia repair, are associated with peritoneal tissue attachment formation and resultant visceral complications. We evaluated attachment formation, fastener engagement, and mesh/tissue integration associated with laparoscopic fixation using a novel permanent capped helical coil fastener (HC-Capped) compared to permanent non-capped helical coil fasteners (HC-Non-Capped) in a porcine model.

Methods

Twelve female pigs underwent bilateral laparoscopic intraperitoneal fixation of Composix? L/P Mesh (10 × 15 cm oval) with HC-Capped or HC-Non-Capped fasteners. Thirty-two fasteners were used to secure each mesh utilizing a “double-crown” technique. Laparoscopy at 30 days was used to evaluate the presence and area coverage of attachments (Diamond Score) and percentage of engaged fasteners. At 90 days, following necropsy, each mesh was evaluated for the presence, percentage, and tenacity (Butler Score) of attachments and fastener engagement. Samples were biomechanically evaluated to assess tissue integration via T-peel testing.

Results

HC-Capped fasteners demonstrated a significantly lower attachment area score compared to the HC-Non-Capped group at 30 days (0.92 ± 0.26 vs. 2.50 ± 0.29/3.00, p = 0.002) and 90 days (0.60 ± 0.22 vs. 2.08 ± 0.29/3.00, p = 0.004). At 90 days, the HC-Capped group evidenced significantly lower attachment tenacity score (1.00 ± 0.37 vs. 2.75 ± 0.33/4.00, p = 0.013). Furthermore, at 30 and 90 days, a significantly greater percentage of HC-Capped fasteners remained properly engaged (30 days: 99.7 % vs. 86.5 %, p < 0.001 and 90 days: 99.4 % vs. 74.5 %, p = 0.001). T-peel biomechanical testing demonstrated significantly greater mesh/tissue integration for HC-Capped group (2.16 ± 0.24 vs. 1.16 ± 0.29 N/cm, p = 0.038).

Conclusions

In a porcine model, HC-Capped fasteners demonstrated significantly less attachment coverage and tenacity in the early postoperative period. Furthermore, the HC-Capped cohort evidenced significantly greater percentage of properly engaged fasteners and greater mesh/tissue integration. Data suggest that shielding exposed fastener points on the visceral mesh surface with polymer caps may reduce attachment formation and aid in mesh fixation and integration.
  相似文献   
679.
MicroRNAs (miRNAs) have a large number of various target genes in different cancer types, which may result in many biological functions. Thus, identifying the molecular mechanisms of miRNAs may effect on the complexity of cancer progression via regulation of gene. In the current study, we utilized real-time PCR to quantify the diction of miR-148b in trail hepatocellular carcinoma (HCC) specimen and normal tissues. Furthermore, we evaluated the relationship of miR-148b and clinicopathological features with survival of HCC patients. Therefore, we evaluated the level of miR-148b expression in 101 HCC patients and also in 40 normal control cases. The result suggested lower expression in tumor tissues than normal control tissues (0.96?±?0.14; 1.84?±?0.20, P?<?0.05). Our findings suggest that the declined expression of miR-148b can considerably be linked to tumor node metastasis (TNM) stage (stages III and IV; P?=?0.021) and vein invasion (P?=?0.029). Nevertheless, miR-148b expression was not related to sex (P?=?0.674), age (P?=?0. 523), size of tumor (P?=?0.507), liver cirrhosis, and histologic grade (P?=?0.734). Survival analysis showed that low expression was remarkably related to overall survival (P?=?0.012). Furthermore, multivariate survival test suggested that decline of miR-148b diction was linked to poor survival in HCC patients. Our results suggested that miR-148b is decreased in HCC. Therefore, we concluded that miR-148b may play its role in the prognosis of HCC.  相似文献   
680.
The objective of the present study was to compare the effects of continuous ultrasound (CUS) with pulsed ultrasound (PUS) in patients with chronic rhinosinusitis (CRS). In this prospective, randomized, double-blind, parallel group study, 40 patients (10 losses) with CRS participated. Patients received either continuous or pulsed (1:9) 1 MHz ultrasound (US) using a US head of 1?cm2 at 1 W/cm2 and 0.5 W/cm2 for the maxillary and frontal sinuses, respectively. Treatment was performed in 10 sessions, 3 days per week, with US given every other day. The primary outcome measure was percent improvement in the Sinusitis Symptom Score. Measurements were taken before and after 10 treatment sessions. The patients were followed up monthly for 2 months. After treatment, both groups improved significantly on the Sinusitis Symptoms Score. Patients who received PUS had significantly decreased total symptom scores compared with patients receiving CUS (mean change 9.8 vs. 5.6, p?=?0.049). The percent improvement in the Sinusitis Symptom Score between the PUS group (65.2 SD 23.1) and the CUS group (43.9 SD 40.7) was not statistically significant (p?=?0.09). The effect size for each treatment was large; PUS: d?=?3.92 and CUS: d?=?1.93. Symptom improvement in both groups was similar at the 2-month follow-up. These results support the use of therapeutic US for CRS. This pilot study gives only marginal evidence to favor PUS over CUS.  相似文献   
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