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991.
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993.
We are reporting 3 cases of pediatric endobronchialtumors presented with recurrent pneumonia. The median age of patients, at time of presentation, was 10.6 years. All patients presented with recurrent pneumonia with a mean time to occurrence, after onset of symptoms, of 14 mo. Bronchoscopy was early performed as part of diagnostic work-up and it revealed an endobronchial mass in every case. Complete surgical resection was performed in all cases, with lung preservation in two of them. Neither post-operative chemotherapy nor radiotherapy was required. The mean duration of follow-up was 7 years and all patients are still alive and disease-free. Recurrent pneumonia, in pediatrics, should raise the suspicion of an obstructing lesion, congenital malformation or systemic disease. A systematic approach is useful for organize the clinicians initial workup. Prompt diagnosis allows parenchymal-sparing surgery, which offers the best chance of cure and reduces clinical and functional complications in these patients.  相似文献   
994.
Chondrosarcoma is a malignant cartilaginous tumor that rarely occurs in the maxillofacial bones. A 44-year-old woman complained about swelling and mild pain during mastication in the right parasymphysis region. Clinical and radiographic examinations revealed characteristics of osteosarcoma. A microscopic examination revealed an abundant proliferation of malignant neoplastic cartilage cells of varying sizes arranged as immature tissue and the absence of an osteoid matrix. This article presents a case of chondrosarcoma of the jaw and discusses the differences between osteosarcoma and chondrosarcoma.  相似文献   
995.
The presence of milk in meals and products consumed daily is common and at the same time the adoption of a milk-free diet increases due to milk allergy, lactose intolerance, vegan diets, and others. Therefore, there is an increasing demand for plant-based beverages, which present variable and, sometimes, unknown nutritional characteristics. This study sought to compare the nutritional aspects of plant-based beverages used as substitutes for cow’s milk described in scientific studies. Therefore, we used a review of the scientific literature on PubMed, Google Scholar, Scopus, Web of Science, Google Patents, Embase, and ScienceDirect databases. The inclusion criteria were scientific studies referring to plant-based beverage used as an alternative to cow’s milk; published in the English language; present data on the serving size, ingredients, and nutritional composition, containing at least data on energy and macronutrients of plant-based beverages. Ingredients and data on energy, macronutrients, and, if available, dietary fiber and some micronutrients of plant-based beverages were collected. Data were obtained from 122 beverages of 22 different matrices, with soy being the most used (27.87%, n = 34). The variation in the amount of nutrients found was 6–183 Kcal/100 mL for energy value; 0.00–22.29 g/100 mL for carbohydrate; 0.06–12.43 g/100 mL for protein; 0.00–19.00 g/100 mL for lipid; 0.00–4.40 g/100 mL for dietary fiber; 0.00–1252.94 mg/100 mL for calcium; 0.04–1.40 mg/100 mL for iron; 0.84–10,178.60 mg/100 mL for magnesium; 0.00–343.43 mg/100 mL for sodium. Salt was the most commonly found added ingredient in plant-based beverages. Some beverages have reached certain amounts of cow’s milk nutrients. However, studies have pointed out differences in their qualities/types. Thus, attention is needed when replacing milk with these alternatives.  相似文献   
996.
According to Process Analytical Technology perspective, drug product quality should be ensured by manufacturing process design. Initial step of the process analysis is investigation of critical process parameters (CPPs). It is generally accepted to type the CPPs based on project team knowledge and experience [5]. This paper describes the use of Design of Experiments tool for selection of the CPPs. Seven factors of wet granulation process were investigated for criticality. Low and high levels of each factor represented maximal and minimal settings of wide operational ranges. Granulates were produced in line with Plackett-Burman experimental matrix, blended with extra-granular excipients and compressed into tablets. Semi-products and final products were tested. Out of specification result of any critical quality attribute was treated as critical failure. The high-shear granulation factors, i.e. quantity of binding solution, rotational speed of impeller and wet massing time were considered of critical importance. Operational ranges of the parameters were optimized. The process performance was confirmed in qualification trials.  相似文献   
997.
A cytotoxicity-guided fractionation of the roots of Galianthe thalictroides afforded a new β-carboline alkaloid, 1-(hydroxymethyl)-3-(2-hydroxypropan-2-yl)-2-(5-methoxy-9H- β-carbolin-1-yl)cyclopentanol, which exhibited strong cytotoxic activity against three human cancer cell lines (MCF-7, 786-0, and UACC62). Its structure was established on the basis of 1D- and 2D-NMR spectroscopic techniques supported by HRMS data.  相似文献   
998.
Solanum lycocarpum A. St. Hil. (Solanaceae) is a hairy shrub or small much-branched tree of the Brazilian Cerrado. S. lycocarpum fruits are commonly used in traditional medicine in powder form or as folk preparations for the treatment of diabetes and obesity, as well as for controlling cholesterol levels. The aim of the present study was to chemically characterize the hydroalcoholic extract (SL) of S. lycocarpum by determination of total flavonoids and total poyphenols and quantification of steroidal alkaloids, as well as to evaluate its mutagenic and/or antimutagenic potential on V79 cells and Swiss mice using chromosomal aberrations and bone marrow micronucleus assays, respectively. Three concentrations of SL (16, 32, and 24?μg/mL) were used for the evaluation of its mutagenic potential in V79 cells and four doses (0.25, 0.50, 1.0, and 2.0?g/kg body weight) were used for Swiss mice. In the antimutagenicity assays, the different concentrations of SL were combined with the chemotherapeutic agent doxorubicin (DXR). HPLC analysis of SL gave contents of 6.57?%?±?0.41 of solasonine and 4.60?%?±?0.40 of solamargine. Total flavonoids and polyphenols contents in SL were 0.04 and 3.60?%, respectively. The results showed that not only SL exerted no mutagenic effect, but it also significantly reduced the frequency of chromosomal aberrations induced by DXR in both V79 cells and micronuclei in Swiss mice at the doses tested.  相似文献   
999.
Morbilliviruses are important pathogens of humans, ruminants, carnivores and marine mammals. Although good vaccines inducing long-term immunity are available, recurrent outbreaks of measles, canine distemper and peste des petits ruminants (PPR) are observed. In control strategies, antivirals thus could be useful to confine virus spread and application of interfering RNAs is a promising approach, provided they can be delivered efficiently into the host cells. We have constructed recombinant adenovirus and baculovirus vectors expressing short hairpin RNAs (shRNAs) against the PPR virus (PPRV) and compared them in vitro. It was found that both recombinant viruses inhibited PPRV replication with the baculovirus vector, which inhibited generation of infectious progeny by more than 2 log10 and the nucleoprotein expression of PPRV by 73%, being the more efficient. The results show that baculoviral shRNA-expressing vectors have the potential for therapeutic use against morbillivirus infections.  相似文献   
1000.
It has recently been established that the use of proteomics can be a useful tool in the field of ecotoxicology. Despite the fact that the mussel Dreissena polymorpha is a valuable bioindicator for freshwater ecosystems, the application of a proteomic approach with this organism has not been deeply investigated. To this end, several zebra mussel specimens were subjected to a 7-day exposure of two different concentrations (0.1 and 2 μg L?1) of the model pollutant benzo[α]pyrene (B[α]P). Changes in protein expression profiles were investigated in gill cytosolic fractions from control/exposed male and female mussels using 2-DE electrophoresis. B[α]P bioaccumulation in mussel soft tissue was also assessed to validate exposure to the selected chemical. We evaluated overall changes in expression profiles for 28 proteins in exposed mussels, 16 and 12 of which were, respectively, over- and under-expressed. Surprisingly, the comparative analysis of protein data sets showed no proteins that varied commonly between the two different B[α]P concentrations. Spots of interest were manually excised and analysed by MALDI-TOF/TOF mass spectrometry. The most significant proteins that were identified as altered were related to oxidative stress, signal transduction, cellular structure and metabolism. This preliminary study indicates the feasibility of a proteomic approach with the freshwater mussel D. polymorpha and provides a starting point for similar investigations. Our results confirm the need to increase the number of invertebrate proteomic studies in order to increase the following: their representation in databases and the successful identification of their most relevant proteins. Finally, additional studies investigating the role of gender and protein modulation are warranted.  相似文献   
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