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61.
Human papillomavirus (HPV) is 1 of the possible aetiological factors in the development of oesophageal squamous cell carcinoma (ESCC). We aimed to study the role of HPV in ESCC. 140 cases of ESCC were analysed for the HPV DNA by polymerase chain reaction (PCR) using GP5+/GP6+ primers for L1 open reading frame (ORF) to amplify a 150 bp segment of HPV L1 ORF. This region was subsequently sequenced to identify the type of HPV. Of the 140 patients enrolled to our study 50.7% were female and 49.3% were male, aged between 20 and 81 y. 33 tumour specimens (23.6%) and 12 (8.6%) non-involved tumour margins were HPV positive. From HPV positive tumour cases 36% were positive in tumour margins. The HPV positive cases were 21.7% male and 25.3% female. There is no correlation between presence and types of HPV with patients' gender and age. The frequency of HPV subtypes in tumoural regions was as follows: HPV-16, 60.6%; HPV-18, 30.3%; HPV-33, 6.1%; and HPV-31, 3%. We found only HPV-16 in tumour margins. Our results are consistent with HPV studies conducted in other high-risk areas for ESCC and provided further evidence to support a causal association of HPV infection with ESCC.  相似文献   
62.
The current study was performed to determine whether application of arteriotomy closure devices (ACDs) affect bleeding complications as compared to manual compression in patients with ST-elevated acute myocardial infarction (STEMI) who undergo primary or rescue percutaneous intervention (PCI). 314 consecutive cases of STEMI treated with PCI were retrospectively evaluated. Overall, 82.8% of patients received ACDs with total bleeding rate of 4.2% vs. 11.1% in patients who had manual compression, p=0.042. This difference in bleeding rates did not correlate with any clinical characteristic or utilization of GPIIb/IIIa inhibitors. Accordingly, ACDs can improve the acute results of PCI in STEMI patients.  相似文献   
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64.
Induction of the innate immune response in newly hatched chickens is important to reduce the risk infection with bacteria, such as Salmonella enteritidis. CpG oligodeoxynucleotides (CpG-ODNs) can stimulate the innate immune response of young chickens. In this study, 2-day-old chickens were treated with CpG-ODN (treatment) or phosphate buffered saline (PBS) solutions (control). Chickens in each group were orally challenged with S. enteritidis at 3 h and 4, 7, and 14 days after the administration of CpG-ODN and PBS solutions. A significant reduction (P?<?0.05) in colonization of S. enteritidis was observed in chickens 3 h after treatment with CpG-ODN. Regardless of the time of inoculation, fewer liver and spleen infected with S. enteritidis were observed in the treatment group than those in the control groups (P?<?0.05). This study demonstrated that CpG-ODN is able to enhance the immune response and resistance to S. enteritidis in neonatal chickens.  相似文献   
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66.
Over the years, Friedel–Crafts (FC) reactions have been acknowledged as the most useful and powerful synthetic tools for the construction of a special kind of carbon–carbon bond involving an aromatic moiety. Its stoichiometric and, more recently, its catalytic procedures have extensively been studied. This reaction in recent years has frequently been used as a key step (steps) in the total synthesis of natural products and targeted complex bioactive molecules. In this review, we try to underscore the applications of intermolecular and intramolecular FC reactions in the total syntheses of natural products and complex molecules, exhibiting diverse biological properties.

In this review, we try to underscore the applications of intermolecular and intramolecular FC reactions in the total syntheses of natural products and complex molecules, exhibiting diverse biological properties.  相似文献   
67.
The presence of heavy metal ions in drinking and wastewater generates environmental and human health concerns as they are known as cumulative poisons. Therefore, the purification of contaminated waters is an important ecological issue. Various techniques have been developed to address this issue, where adsorption has received widespread attention. The facile synthesis of effective adenine-based nano-adsorbents is reported and adsorptive removal of Ni2+, Cd2+, and Pb2+ from aqueous media was investigated by inductively-coupled plasma analyses, adsorption isotherms, kinetics, and thermodynamic studies. The effects of pH, adsorbent dose, contact time, and temperature were optimized. The maximum adsorption capacity was achieved at pH = 7, an adsorbent dose of 25 mg, and an initial concentration of 50 mg L−1 at 25 °C. A thermodynamic study showed that adsorption is an endothermic process, and the Langmuir model fitted well to the ion adsorption data to reveal that the maximum adsorption capacities for Ni2+, Cd2+, and Pb2+ were 273.7, 252.4, and 249.8 mg g−1, respectively.

The presence of heavy metal ions in drinking and wastewater generates environmental and human health concerns as they are known as cumulative poisons.  相似文献   
68.
A simple, rapid and sensitive method for analysis of xylene and toluene was developed using the solid-phase microextraction (SPME) combined with ion mobilityspectrometry (IMS). Gold nanoparticles–thiol silane film (Au NPs–TSF) was applied as a newsorbent for SPME. Thiol silane film was formed on the surface of a stainless steel wire through incorporating Au nanoparticles during synthesis using sol–gel technique. The extraction properties of the fiber to xylene and toluene were examined, using a SPME device and thermal desorption ininjection port of IMS. The calibration graphs were linear in the range of 1.10–32.0 and 16.0–112.0 ppb for xylene and toluene, respectively. The detection limits for xylene and toluene were 0.7 and 8.0 ppb, respectively. The proposed method was applied without any considerable sample pretreatment and it was found to be simple enough to be strongly recommended for real sample analysis.  相似文献   
69.
Numerous kidney exchange (kidney paired donation [KPD]) registries in the United States have gradually shifted to high‐frequency match‐runs, raising the question of whether this harms the number of transplants. We conducted simulations using clinical data from 2 KPD registries—the Alliance for Paired Donation, which runs multihospital exchanges, and Methodist San Antonio, which runs single‐center exchanges—to study how the frequency of match‐runs impacts the number of transplants and the average waiting times. We simulate the options facing each of the 2 registries by repeated resampling from their historical pools of patient‐donor pairs and nondirected donors, with arrival and departure rates corresponding to the historical data. We find that longer intervals between match‐runs do not increase the total number of transplants, and that prioritizing highly sensitized patients is more effective than waiting longer between match‐runs for transplanting highly sensitized patients. While we do not find that frequent match‐runs result in fewer transplanted pairs, we do find that increasing arrival rates of new pairs improves both the fraction of transplanted pairs and waiting times.  相似文献   
70.
Current strategies of tissue engineering are focused on the reconstruction and regeneration of damaged or deformed tissues by grafting of cells with scaffolds and biomolecules. Recently, much interest is given to scaffolds which are based on mimic the extracellular matrix that have induced the formation of new tissues. To return functionality of the organ, the presence of a scaffold is essential as a matrix for cell colonization, migration, growth, differentiation and extracellular matrix deposition, until the tissues are totally restored or regenerated. A wide variety of approaches has been developed either in scaffold materials and production procedures or cell sources and cultivation techniques to regenerate the tissues/organs in tissue engineering applications. This study has been conducted to present an overview of the different scaffold fabrication techniques such as solvent casting and particulate leaching, electrospinning, emulsion freeze-drying, thermally induced phase separation, melt molding and rapid prototyping with their properties, limitations, theoretical principles and their prospective in tailoring appropriate micro-nanostructures for tissue regeneration applications. This review also includes discussion on recent works done in the field of tissue engineering.  相似文献   
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