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51.
Purpose:To provide a retrospective analysis of lesions of the caruncle which have been very rarely reported in the literature.Methods:A retrospective review of all the caruncular lesions between January 2000 and January 2020 was done at a single tertiary eye care hospital. The lesions were classified as benign and malignant lesions. Clinicopathological correlation was done for the excised lesions.Results:A total of 87 caruncular lesions were included in the study. Males (59%) were affected more than females (41%). The mean age at presentation was 44 ± 20 years. The mean duration of complaint was 36 ± 62 months. A total of 36 patients underwent surgical excision whereas the rest opted for conservative management. Recurrence was noted in five patients. Fifteen different types of lesions were identified histopathologically. Benign lesions (78%) were far more common than malignant ones (22%). Epithelial inclusion cyst was the most common benign lesion and sebaceous gland carcinoma was the most common malignant lesion. Correct clinicopathological correlation was seen in 52.7% of the cases. Caruncular tuberculosis, oncocytoma, and basosquamous cell carcinoma were some of the rare lesions.Conclusion:Caruncular lesions are uncommon and very diverse, which makes clinical diagnosis challenging. Epithelial inclusion cyst and sebaceous gland carcinoma were the most common benign and malignant lesions respectively. Correct clinicopathological correlation was seen in more than half of the cases.  相似文献   
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Phage therapy is a promising biocontrol management on plant diseases caused by bacterial pathogens due to its specificity, efficiency and environmental friendliness. The emergence of natural phage-resistant bacteria hinders the application of phage therapy. Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of the devastating bacterial leaf blight disease of rice. Here, we obtained a spontaneous mutant C2R of an Xoo strain C2 showing strong resistance to the lytic phage X2. Analysis of the C2R genome found that the CDS2289 gene encoding glycosyltransferase acquired a frameshift mutation at the 180th nucleotide site, which also leads to a premature stop mutation at the 142nd amino acid. This mutation confers the inhibition of phage adsorption through the changes in lipopolysaccharide production and structure and bacterial surface morphology. Interestingly, glycosyltransferase-deficient C2R and an insertional mutant k2289 also showed reduced virulence, suggesting the trade-off costs of phage resistance. In summary, this study highlights the role of glycosyltransferase in interactions among pathogenic bacteria, phages and plant hosts, which provide insights into balanced coevolution from environmental perspectives.  相似文献   
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A combined emulsion/polymer cross-linking/solvent evaporation technique was used to prepare magnetic chitosan microspheres (MCM) containing the anticancer drug, oxantrazole. A central composite experimental design was used to simultaneously evaluate a variety of formulation factors on a number of response variables, such as the percentage of oxantrazole entrapped in the MCM. In association with the study design, statistical optimization procedures indicated the factors that significantly influence MCM preparation and what levels of the factors are needed to produce optimum MCM. Entrapment of anticancer agents into biodegradable microspheres is difficult because of low aqueous drug solubility and porosity of the particles. The latter effect was circumvented by a chitosan cross-linking step that resulted in 3% (w/w) oxantrazole entrapment in the MCM via the optimization procedures. The combined formulation and statistical optimization strategy provide a basis to develop other microparticulate systems and led to a dosage form that can be used for future in vivo investigations.  相似文献   
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In the present work, three different woven composite laminates were fabricated using the hand lay-up method. The woven reinforcement fibres were carbon fibres (CFRP), glass fibres (GFRP-W) and (GFRP-R) in combination with epoxy resin. Then, the central notch specimen tensile test (CNT) was used to measure the fracture toughness and the corresponding surface release energy (GIC). Then, the data were compared with the essential work of fracture (we) values based on the stored energy of the body to obtain a new standard fracture toughness test for composite laminates using relatively simple techniques. In addition to an extended finite element model, XFEM was implemented over a central notch specimen geometry to obtain a satisfactory validation of the essential work of fracture concepts. Therefore, the average values of (GIC) were measured with CNT specimens 25.15 kJ/m2, 32.5 kJ/m2 and 20.22 kJ/m2 for CFRP, GFRP-W and GFRP-R, respectively. The data are very close as the percentage error for the surface release energy measured by the two methods was 0.83, 4.6 and 5.16 for carbon, glass and random fibre composite laminates, respectively. The data for the fracture toughness of XFEM are also very close. The percentage error is 4.6, 5.25 and 2.95 for carbon, glass and random fibre composite laminates, respectively. Therefore, the fundamental work of the fracture concept is highly recommended as a fracture toughness test for composite laminates or quasi-brittle Material.  相似文献   
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This study was aimed to evaluate the efficacy of crude aqueous-methanol and aqueous extracts of neem (Azadirachta indica) seed kernel against sarcoptic mange of sheep. Crude aqueous-methanol (AME) and aqueous extracts (AE) of neem seed kernel (NSK) were prepared and formulated as 10% and 20% ointments (w/w), using Vaseline as vehicle. Forty-two lambs of Pak Karakul breed, having natural infection of sarcoptic mange were divided into seven experimental groups. Skin scrapings and clinical examination were carried out at scheduled intervals after treatment. Ivermectin (positive control) completely cleared infesting mites from animals after 10 days and 20% AME after 16 days. While, clinical mange was completely cured after 16 and 20 days with ivermectin and 20% AME, respectively, under field conditions. Only the higher concentration (20% AME) of NSK extracts completely cured the clinical mange, suggesting a dose-dependent response. Our results consolidate the belief that use of folk remedies can provide an effective and economic way of combating sarcoptic mange in sheep.  相似文献   
60.
Abstract Objective: The receptor for advanced glycation end products (RAGE) has been proposed to participate in the innate and adaptive immune responses. RAGE can induce production of pro-inflammatory cytokines and chemokines, as well as neutrophil chemotaxis in a manner that may be suppressed or stimulated by soluble, truncated forms of RAGE including the soluble form of RAGE (sRAGE) and endogenous secretory RAGE (esRAGE). The objective of this study was to determine whether intra-amniotic infection/inflammation (IAI) is associated with changes in the amniotic fluid concentration of sRAGE and esRAGE. Study design: Amniotic fluid (AF) was retrieved from patients in the following groups: 1) mid-trimester (14-18 weeks of gestation; n=68); 2) term not in labor (n=24); 3) term in labor (n=51); 4) preterm labor and intact membranes (n=124); and 5) preterm PROM (n=80). Intra-amniotic infection and inflammation were defined as the presence of a positive amniotic fluid culture for microorganisms and an AF interleukin-6 concentration >/=2.6 ng/mL, respectively. The AF concentration of sRAGE and esRAGE were determined using specific and sensitive ELISAs which measured total immunoreactive sRAGE and esRAGE, respectively. Patients were matched for gestational age at amniocentesis to compare the AF concentration of sRAGE and esRAGE in patients with and without IAI. Non-parametric statistics were used for analysis and a P<0.05 was considered significant. Results: 1) Patients at term not in labor had higher median AF concentrations of sRAGE and esRAGE than those in the mid-trimester (P<0.001 for both comparisons) and those at term in labor (P=0.03 and P=0.04, respectively); 2) patients with preterm labor and intact membranes with intra-amniotic infection/inflammation (IAI) had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.02 and P=0.005, respectively); 3) similarly, patients with preterm PROM with IAI had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.03 and P=0.02, respectively). Conclusion: Intra-amniotic infection/inflammation is associated with increased amniotic fluid concentrations of sRAGE and esRAGE. Changes in the amniotic fluid concentration of sRAGE and esRAGE may represent part of the immune response to intra-amniotic infection/inflammation.  相似文献   
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