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91.
There is an increasing demand for age estimations of living persons who are involved in civil and criminal procedures but lack a valid birth certificate indicating their date of birth. Several studies have recommended the application of magnetic resonance imaging (MRI) and assessment of the stage of epiphyseal fusion in age estimation. This study involved retrospective MRI analysis of 335 cases (217 males and 118 females) whose ages ranged from 8 to 28 years (yrs). We assessed the degree of ossification of the proximal tibial epiphysis depending on the classifications of Schmeling and Kellinghaus used for the main stages (I, II, III, IV & V) and substages (IIa, b, c & IIIa, b, c). Significant differences between males and females at stages IIIc, IV and V (p < 0.001) were observed. Additionally, the ossification of the proximal tibial epiphyses occurred earlier in females than in males (2–4 yrs). The mean of ages in stage IV was approximately 18.6 yrs. in females and 22.5 yrs. in males, meaning that stage IV can be used as a valuable forensic marker to determine whether the person in question has reached the age of 18 yrs. We concluded that the application of MRI in the assessment of the ossification status of the proximal tibial epiphysis could be helpful in age estimation for various forensic purposes.  相似文献   
92.

Purpose

Tagged and cine magnetic resonance imaging (tMRI and cMRI) techniques are used for evaluating regional and global heart function, respectively. Measuring global function parameters directly from tMRI is challenging due to the obstruction of the anatomical structure by the tagging pattern. The purpose of this study was to develop a method for processing the tMRI images to improve the myocardium-blood contrast in order to estimate global function parameters from the processed images.

Materials and methods

The developed method consists of two stages: (1) removing the tagging pattern based on analyzing and modeling the signal distribution in the image’s k-space, and (2) enhancing the blood-myocardium contrast based on analyzing the signal intensity variability in the two tissues. The developed method is implemented on images from twelve human subjects.

Results

Ventricular mass measured with the developed method showed good agreement with that measured from gold-standard cMRI images. Further, preliminary results on measuring ventricular volume using the developed method are presented.

Conclusion

The promising results in this study show the potential of the developed method for evaluating both regional and global heart function from a single set of tMRI images, with associated reduction in scan time and patient discomfort.
  相似文献   
93.

Objective

Rotator cuff tears are one of the most common causes of chronic shoulder pain and disability. They significantly affect the quality of life. Reduced pain and improved function are the goals of conventional therapy, which includes relative rest, pain therapy, physical therapy, corticosteroid injections and surgical intervention. Tendons have a relative avascular nature; hence, their regenerative potential is limited. There is some clinical evidence that the application of autologous platelets may help to revascularize the area of injury in rotator cuff pathologies.

Patients and methods

This prospective randomized controlled study was done to evaluate the results of subacromial injection of platelet-rich plasma (PRP) versus corticosteroid injection therapy in 40 patients with symptomatic partial rotator cuff tears. All patients were assessed before injection, 6 weeks, 3 and 6 months after injection, using the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), the Constant–Murley Score (CMS), the Simple Shoulder Test (SST) and a Visual Analog Scale (VAS) for pain. An MRI was performed before and 6 months after the injection for all the included patients and was graded on 0–5 scale.

Results

Both injection groups showed statistically significantly better clinical outcomes over time compared with those before injection. There was a statistically significant difference between RPP group and corticosteroid group 12 weeks after injection, regarding VAS, ASES, CMS and SST in favor of the RPP group. MRI showed an overall slight nonsignificant improvement in grades of tendinopathy/tear in both groups, however, without statistically significant differences between the two groups.

Conclusion

PRP injections showed earlier better results as compared to corticosteroid injections, although statistically significant better results after 6 months could not be found. Therefore, subacromial RPP injection could be considered as a good alternative to corticosteroid injection, especially in patients with a contraindication to corticosteroid administration.

Level of evidence

II.
  相似文献   
94.
The therapeutic effect of pegylated interferon (peg‐IFN) alfa‐2a combined with ribavirin (RBV) on chronic hepatitis C Egyptian patients is low and further efforts are required to optimize this therapy for achievement of higher rates of virological response. This study aimed to evaluate the safety and efficacy of hydroxychloroquine (HCQ) in combination with pegylated interferon plus ribavirin on early virological response (EVR) in chronic hepatitis C Egyptian patients. Naïve 120 Egyptian patients with chronic hepatitis C virus infection were divided into two groups. Group 1 have administered the standard of care therapy (pegylated interferon alfa‐2a plus ribavirin) for 12 weeks, (n = 60). Group 2 have administered hydroxychloroquine plus standard of care therapy for 12 weeks, (n = 60). Therapeutics included hydroxychloroquine (200 mg) oral twice daily, peginterferon alfa‐2a (160 μg) subcutaneous once weekly and oral weight‐based ribavirin (1000–1200 mg/day). Baseline characteristics were similar in the two groups. The percentage of early virological response was significantly more in patients given the triple therapy than in patients given the standard of care [54/60 (90%) vs. 43/60 (71.7%); P = 0.011; respectively]. Biochemical response at week 12 was also significantly higher in patients given the triple therapy compared with the standard of care [58/60 (96.7%) vs. 42/60 (70%); P < 0.001; respectively]. Along the study, the observed adverse events were mild and similar across treatment groups. Addition of hydroxychloroquine to pegylated interferon plus ribavirin improves the rate of early virological and biochemical responses in chronic hepatitis C Egyptian patients without an increase in adverse events. J. Med. Virol. 88:2170–2178, 2016. © 2016 Wiley Periodicals, Inc.
  相似文献   
95.
Chitosan biguanidine hydrochloride (ChG) and glutaraldehyde cross-linked chitosan biguanidine (CChG) were synthesized and characterized by Fourier transform infrared spectroscopy, 1H NMR and 13C NMR, X-ray diffraction, scanning electron microscopy (SEM) and thermal analyses (TGA and DTA). The results showed that ChG and CChG had a more amorphous structure than that of chitosan, and their thermal stability were slightly lower than that of chitosan. Colloidal silver nanoparticles (AgNPs) were prepared using borohydride reduction method and then investigated as fillers in partially cross-linked chitosan biguanidine. The obtained nanoparticles were uniform and spherical with average size of 9.6 ± 0.5 nm. The prepared CChG/AgNPs composites were characterized for their morphology, thermal properties, cytotoxicity and antimicrobial activity. The SEM images showed that the AgNPs are well imbedded in the CChG matrix. The thermal stability of CChG was improved with incorporation of AgNPs. The CChG and CChG/AgNPs showed less cytotoxicity to breast cancer cells (MCF-7). Compared with chitosan and CChG, the ChG and CChG/AgNPs showed better antimicrobial activity against Streptococcus pneumoniae and Bacillus subtilis as Gram-positive bacteria, Escherichia coli as Gram-negative bacteria and Aspergillus fumigatus, Geotricum candidum and Syncephalastrum recemosum as fungi.  相似文献   
96.

Objectives:

To evaluate Ki67 immunoexpression pattern in Saudi breast cancer (BC) patients and investigate any possible predictive or prognostic value for Ki67.

Methods:

This is a retrospective study designed to quantitatively assess the Ki67 proliferative index (PI) in retrieved paraffin blocks of 115 Saudi BC patients diagnosed between January 2005 and March 2015 at the Department of Pathology, King Fahd Hospital, Al Madinah Al Munawarah, Kingdom of Saudi Arabia. The Ki67 PI was correlated with individual and combined immunoprofile data of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2/neu) with their clinicopathological parameters.

Results:

Ki67 immunoreactivity was highly expressed (>25% of the tumor cells were positive) in 85 (73.9%) patients. The Ki67 PI was significantly associated with poor prognostic clinicopathological parameters including old age (p<0.02), high tumor grade (p<0.01), lymph node metastasis (p<0.001), and Her-2/neu positivity (p<0.009). However, the association with ER positivity, PR positivity, tumor size, and lymphovascular invasion were not statistically significant. The Ki67 PI was significantly associated with BC molecular subtypes that were Her2/neu positive (luminal B and HER-2) subtypes compared with the Her2/neu negative (luminal A) subtype (p<0.04).

Conclusion:

The Ki67 PI is significantly higher in Saudi BC patients comparing with the reported literature. Ki67 PI was highest in the HER-2 and luminal-B molecular subtypes. Along with other prognostic indicators, Ki67 PI may be useful in predicting prognosis and management of Saudi BC patients.Breast cancer (BC) is one of the most common malignancy in the world.1 Although in the Kingdom of Saudi Arabia (KSA), the incidence of BC is much lower than in the Western world; it is still the most common malignancy in the Saudi women. According to the Saudi Cancer registry,2 BC accounted for approximately 23% of all the newly diagnosed female cancers. An additional significant fact on BC in KSA is its special presentation; as it predominantly affects the younger population, frequently presents as higher histological grades and in advanced clinical stages.2-4 Apart from the problem of its being highly prevalent globally and locally; BC has also shown its divergent nature with regards to its clinical course, response to treatment, and prognostic outcomes. Thus, the new molecular classification of BC has emerged on the basis of biomarkers. In the initial stages, the hormones namely, the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (Her2) played their roles. It was only 15 years ago, that the molecular classification of BC was proposed by Californian scientists, initially there were 4 major classes: luminal-like, basal-like, normal-like, and Her2 positive.5 Consequently, a fifth class was added, dividing one of the major luminal class to luminal A and luminal B classes.6-8 Ki67 had been known to be an important proliferation biomarker since 1980s. It has recently become an essential component of routine biomarker profile for BC, along with ER, PR, and Her2, to assist the oncologists in delivering optimum treatment to BC patients. Its role as a poor prognostic biomarker is well established, and a number of studies have found a significant correlation between Ki67 positivity with that of histological parameters such as nuclear grades and mitotic figures.9 Recent studies have also proved its predictive role in both the antihormonal therapy and chemotherapy for the efficacy of the treatment. The aim of this study is to examine the Ki67 biomarker in the BC patients and the immunohistochemically on the paraffin embedded blocks. Subsequently, to correlate the Ki67 findings with individual and combined immunoprofile data of ER, PR, and Her2/neu, as well as with their clinicopathological parameters to identify any specific differences in our BC cases as compared with western cases. This is may be important in investigating any predictive or prognostic role of Ki67 in managing BC patients in KSA population.  相似文献   
97.
98.
A series of novel phthalimide analogs containing an indole or brominated indole moiety were synthesized and their antimicrobial activity was evaluated. Compound 8 showed a broad spectrum activity, revealing 53–67% of erythromycin activity on the tested bacteria and 60–70% of miconazole activity on the tested fungi. Anticancer activity was evaluated on the cell lines HepG2, MCF‐7, A549, H1299, and Caco2. The results revealed that the new phthalimide analog 8 has broad‐spectrum anticancer activity toward all the tested cancer cell lines, followed by compound 11 , which showed good activity toward all the tested cell lines except for MCF‐7. The ability of the promising analogs 5 , 8 , and 11 to bind to topoisomerase II DNA gyrase was investigated. Caspase‐3 activation and Bcl‐2 assay of the best active derivatives 8 , 11 in addition to compound 5 were evaluated. The antifibrotic activity was studied in an in vivo model and the histopathological studies revealed that treatment with the new compound 8 improved the fibrotic liver tissues to normality.
  相似文献   
99.
The versatile precursor 2-acetyl-4-allyl-1-hydroxy naphthalene was synthesized efficiently via Claisen rearrangement 2-acetyl-1-allyloxynaphthalene. The Claisen-Schmidt condensation of latter precursor afforded the corresponding chalcones which were exploited to synthesize a series of potential heterocycles such as pyrazoline, isoxazoline, benzocoumarin and benzoflavone. The synthesized products showed potent antioxidant and antimicrobial activities. Chalcone 3c, naphthyl pyrazoline 6b and hydroxycoumarin 13 exhibited the highest activity as antioxidants. Their binding mode showed specialized recognition of hydroxycoumarin 13 with the triad key amino acids at the active site of the oxidoreductase enzyme (PDB code 1DXO). 1-Hydroxynaphth-2-yl pyrazoline (6b) revealed the highest efficacy against both Gram positive and negative bacterial species. In silico molecular docking of pyrazoline 6b endorsed its proper binding at the active site of the 2EX6 enzyme which explains its potent antibacterial activity in comparison with standard ampicillin.  相似文献   
100.
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