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991.
Solvothermal reactions of lanthanide (III) salts with 1,2-phenylenediacetic acid in N,N′-dimethylformamide (DMF) solvent lead to the formation of the metal complexes of the general formula Ln2(1,2-pda)3(DMF)2, where Ln(III) = Pr(1), Sm(2), Eu(3), Tb(4), Dy(5), and Er(6), 1,2-pda = [C6H4(CH2COO)2]2−. The compounds were characterized by elemental analysis, powder and single-crystal X-ray diffraction methods, thermal analysis methods (TG-DSC and TG-FTIR), infrared and luminescence spectroscopy. They exhibit structural similarity in the two groups (Pr, Sm, and Eu; Tb, Dy, and Er), which was reflected in their thermal behaviours and spectroscopic properties. Single-crystal X-ray diffraction studies reveal that Sm(2) and Eu(3) complexes form 2D coordination polymers with four crystallographically independent metal centers. Every second lanthanide ion is additionally coordinated by two DMF molecules. The 1,2-phenylenediacetate linker shows different denticity being: penta- and hexadentate while carboxylate groups exhibit bidentate-bridging, bidentate-chelating, and three-dentate bridging-chelating modes. The infrared spectra reflect divergence between these two groups of complexes. The complexes of lighter lanthanides contain in the structure coordinated DMF molecules, while in the structures of heavier complexes, DMF molecules appear in the inner and outer coordination sphere. Both carboxylate groups are deprotonated and engaged in the coordination of metal centers but in different ways in such groups of complexes. In the groups, the thermal decomposition of the isostructural complexes occurs similarly. Pyrolysis of complexes takes place with the formation of such gaseous products as DMF, carbon oxides, ortho-xylene, ethers, water, carboxylic acids, and esters. The complexes of Eu and Tb exhibit characteristic luminescence in the VIS region, while the erbium complex emits NIR wavelength.  相似文献   
992.
Traditionally, treatment of renal lesions is indicated based only on imaging features. Although controversy exists about tissue sampling from small renal masses, renal biopsy is indicated in some cases. In this review, we discuss the rationale for endoscopic ultrasound-guided fine needle aspiration(EUS-FNA) andsummarize the recent advances in this field, providing recommendations for the practicing clinician. The use of EUS-FNA appears to be a safe and feasible means of confirming or excluding malignancy. EUS allows assessment and biopsy of masses or lesions within both kidneys and related complications are rare. The main advantages of EUS-FNA are that it can be done as an outpatient procedure, with good results, minimal morbidity and a short hospital stay. Nevertheless, EUS-FNA of renal masses should be indicated only in selected cases, in which there is potential to decrease unnecessary treatment of small renal masses and to best select tumors for active surveillance and minimally invasive ablative therapies. Additionally, some renal lesions may be ineligible for EUS-guided biopsy because of anatomical limitations. EUS-FNA renal biopsy will probably be best applied to central anterior renal masses, while tumors on the posterior aspect of the kidney, percutaneous access will probably be superior.  相似文献   
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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   
997.
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   
998.
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   
999.
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   
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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