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971.
X-ray analysis were used to study the jejunum and ileum, in vivo. 2019 patients were examined by double contrast small bowel enema. We considered some parameters concerning the folds of its mucous membrane and its thickness and depth. Furthermore, we considered the radiological appearance of the Peyer's patches and solitary lymphatic follicles. The results are according to the literature.  相似文献   
972.
973.
A simple, rapid, sensitive, and specific film assay for collagenase activity employing a glass-supported, reconstituted collagen gel is described. Digestion of the collagen film results in sharply defined zones of lysis detectable by staining with Coomassie blue. The assay is semiquantitative and suitable for micro enzyme determination in biological fluids.  相似文献   
974.
975.
Primary Sjögren’s syndrome (pSS) is a solitary poorly understood autoimmune inflammatory disease by involvement of the salivary and lacrimal glands resulting in dry mouth and dry eyes. Myoepithelial cells (MECs) are cells knowing for its hybrid epithelial and mesenchymal phenotype that are important components of the salivary gland (SGs) structure aiding the expulsion of saliva from acinar lobules. In this study we investigate possible alteration in the myofilament component of MECs in SGs specimens obtained from pSS patients in comparison with healthy subjects, to evaluate MECs hypothetical involvement in the pathogenesis of pSS. The expression of alpha-smooth muscle actin (α-SMA) and p63, as MECs markers, was evaluated in bioptic specimens from pSS and healthy labial SGs through immunohistochemistry and immunofluorescence analyses; the distribution of MECs markers was quantified using Aperio ScanScope and ImageScope software to provide quantitative assessments of staining levels. Our observations demonstrated that p63 nuclear labeling in pSS MECs is preserved whereas α-SMA cytoplasmic staining is strongly and significantly reduced when compared with healthy SGs; the digital images analysis quantification of the expression of labeled α-SMA and p63 protein in the healthy and pSS MECs salivary tissues, led to results suggesting a loss of mechanical support for acini and ducts in pSS, correlated, probably, with the reduction of salivary flow that features one important aspect of pSS disease.  相似文献   
976.
977.
In this work, the first mutual prodrug of 5-fluorouracil and heme oxygenase1 inhibitor (5-FU/HO-1 hybrid) has been designed, synthesised, and evaluated for its in vitro chemical and enzymatic hydrolysis stability. Predicted in silico physicochemical properties of the newly synthesised hybrid (3) demonstrated a drug-like profile with suitable Absorption, Distribution, Metabolism, and Excretion (ADME) properties and low toxic liabilities. Preliminary cytotoxicity evaluation towards human prostate (DU145) and lung (A549) cancer cell lines demonstrated that 3 exerted a similar effect on cell viability to that produced by the reference drug 5-FU. Among the two tested cancer cell lines, the A549 cells were more susceptible for 3. Of note, hybrid 3 also had a significantly lower cytotoxic effect on healthy human lung epithelial cells (BEAS-2B) than 5-FU. Altogether our results served as an initial proof-of-concept to develop 5-FU/HO-1 mutual prodrugs as potential novel anticancer agents.  相似文献   
978.

In ecosystems, plants are continuously challenged by combined stress conditions more than by a single biotic or abiotic factor. Consequently, in recent years studies on plant relationships with multiple stresses have aroused increasing interest. Here, the impact of inoculation with fungal pathogens with different lifestyles on Arabidopsis plants response to the following infestation with the invasive crop pest Eurydema oleracea was investigated. In particular, as fungal pathogens the necrotroph Botrytis cinerea and the biotroph Golovinomyces orontii were used. Plants exposed to B. cinerea, but not to G. orontii, showed reduced herbivore feeding damage. This difference was associated to different hormonal pathways triggered by the pathogens: G. orontii only induced the salicylate-mediated pathway, while B. cinerea stimulated also the jasmonate-dependent signalling, which persisted for a long time providing a long-term defence to further herbivore attack. In particular, the lower susceptibility of B. cinerea-infected Arabidopsis plants to E. oleracea was related to the stimulation of the JA-induced pathway on the production of plant volatile compounds, since treatment with VOCs emitted by B. cinerea inoculated plants inhibited both insect plant choice and feeding damage. These results indicate that necrotrophic plant pathogenic fungi modulate host volatile emission, thus affecting plant response to subsequent insect, thereby increasing the knowledge on tripartite plant–microbe–insect interactions in nature.

  相似文献   
979.
Based on analyses with cryo‐scanning and transmission electron microscopy, the present study reports on the morphology and ultrastructure of the attachment structures of the green stinkbug Nezara viridula L. (Heteroptera: Pentatomidae), a cosmopolitan pest of different crops in most areas of the world. In addition, the presence and distribution of large proportions of the elastic protein resilin in these structures was revealed by confocal laser scanning microscopy. The attachment structures of each leg comprise two sclerotised claws, a pair of smooth flexible pulvilli and a hairy adhesive pad located at the ventral side of the basitarsus. No sexual dimorphism is evident. Contact areas of resting individuals on a smooth surface show that N. viridula creates contact to the substrate with the ventral surface of (a) the distal portions of the pulvilli, (b) the setae of the hairy adhesive pad, (c) the two paraempodia representing mechanosensory setae, and (d) the tips of the claws. Each pulvillus is a sac‐like structure formed by complex cuticular layers that vary in their structure and resilin content. The dorsal side consists of sclerotised chitinous material, while the ventral cuticle consists mainly of resilin and shows a very thin epicuticle and a thick exocuticle. The setae of the hairy adhesive pad are pointed and socketed. They exhibit a pronounced longitudinal gradient in the material composition, with large proportions of resilin being present in the setal tips. In most of these setae, especially in those of the distal‐most part of the pad, also a transverse gradient in the material composition is visible.  相似文献   
980.
Adenine uptake and hypoxanthine release by IMP-enriched human erythrocytes has been studied. The presence of IMP within the erythrocytes leads to an increase in the rate of adenine incorporation. Adenine is taken up by IMP-enriched erythrocytes as AMP, even when intracellular 5-phoshorobosyl-1-pyrophosphate concentration is undetectable and too low to allow IMP synthesis from hypoxanthine. During adenine uptake and AMP synthesis, hypoxanthine is released by the cells. The possibility that 5-phosphoribosyl-1-pyrophosphate, necessary for AMP synthesis, is formed through the hypoxanthine guanine phosphoribosyltransferese-catalyzed IMP pyrophosphorolysis is considered.  相似文献   
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