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81.
目的:研究黄色肉芽肿性胆囊炎(XGC)与胆囊癌的临床特征分析及螺旋CT检查的鉴别诊断价值。方法:选取从2018年1月-2020年12月于我院接受腹部螺旋CT检查的41例XGC患者纳入研究,记作XGC组,另取同期医院接受腹部螺旋CT检查的45例胆囊癌患者作为胆囊癌组。分析两组临床特征、螺旋CT检查结果表现,比较两组血清血管内皮生长因子(VEGF)、糖类抗原19-9(CA19-9)水平的差异。并以病理检查为金标准,分析螺旋CT检查用作XGC与胆囊癌鉴别诊断的价值。结果:XGC组患者食欲下降、体重下降人数占比均低于胆囊癌组(均P<0.05);而两组腹痛、黄疸、发热、白细胞(WBC)升高、谷丙转氨酶(ALT)升高、谷草转氨酶(AST)升高、胆囊扩张发生率对比差异无统计学意义(均P>0.05)。XGC组囊壁增厚均匀、壁内有低密度结节人数占比均低于胆囊癌组,而有肿大淋巴结人数占比高于胆囊癌组(均P<0.05)。螺旋CT检查诊断XGC的灵敏度、特异度、准确度分别为95.12(39/41)、95.56%(43/45)、95.35%(82/86)。XGC组患者血清VEGF、CA19-9水平均低于胆囊癌组,差异均有统计学意义(均P<0.05)。结论:XGC患者食欲下降、体重下降发生率低于胆囊癌患者,螺旋CT检查鉴别诊断XGC与胆囊癌的价值较高,值得临床关注。  相似文献   
82.

Antimicrobial peptides (AMPs) are molecules present in several life forms, possess broad-spectrum of inhibitory activity against pathogenic microorganisms, and are a promising alternative to combat the multidrug resistant pathogens. The aim of this work was to identify and characterize AMPs from Capsicum chinense fruits and to evaluate their inhibitory activities against yeasts of the genus Candida and α-amylases. Initially, after protein extraction from fruits, the extract was submitted to anion exchange chromatography resulting two fractions. Fraction D1 was further fractionated by molecular exclusion chromatography, and three fractions were obtained. These fractions showed low molecular mass peptides, and in fraction F3, only two protein bands of approximately 6.5 kDa were observed. Through mass spectrometry, we identified that the lowest molecular mass protein band of fraction F3 showed similarity with AMPs from plant defensin family. We named this peptide CcDef3 (Capsicum chinense defensin 3). The antifungal activity of these fractions was analyzed against yeasts of the genus Candida. At 200 μg/mL, fraction F1 inhibited the growth of C. tropicalis by 26%, fraction F2 inhibited 35% of the growth of C. buinensis, and fraction F3 inhibited all tested yeasts, exhibiting greater inhibition activity on the growth of the yeast C. albicans (86%) followed by C. buinensis (69%) and C. tropicalis (21%). Fractions F1 and F2 promoted membrane permeabilization of all tested yeasts and increased the endogenous induction of reactive oxygen species (ROS) in C. buinensis and C. tropicalis, respectively. We also observed that fraction F3 at a concentration of 50 µg/mL inhibited the α-amylase activities of Tenebrio molitor larvae by 96% and human salivary by 100%. Thus, our results show that fraction F3, which contains CcDef3, is a very promising protein fraction because it has antifungal potential and is able to inhibit the activity of different α-amylase enzymes.

  相似文献   
83.
目的探究阴道加德纳菌(Gardnerella vaginalis)检出率及唾液酸酶A基因携带与细菌性阴道病(BV)的关系。方法选择2017年1月至2019年8月确诊的BV患者82例作为BV组,并随机选择同时期健康女性82例作为健康组,比较2组人群G. vaginalis检出率和唾液酸酶A基因携带情况,相关统计学资料分析其对BV发生的影响。结果BV组人群G. vaginalis阳性检出率高于健康组(χ2=11.511,P<0.05)。BV组人群共检出G. vaginalis 1、2、3、4、5、6和7型,其中2型占比最高;BV组人群G. vaginalis 2、3、4型占比率高于健康组(χ2=4.148,17.009,9.973,均P<0.05)。BV组人群唾液酸酶A基因携带率高于健康组(χ2=39.234,P<0.05)。较健康组人群,BV组PCR DGGE宽度更窄,肠道菌群条带数少(t=9.217,P<0.05)。结论G. vaginalis检出率和唾液酸酶A基因携带情况与BV发生相关,有待成为相关生物学治疗靶点。  相似文献   
84.
96序列相似的家庭成员A和B(family with sequence similarity 96 member A and B,FAM96A和FAM96B)是属于MIP18(MMS19-interacting protein of 18 kD)家族的2个高度保守的同源蛋白,MIP18是与有丝分裂纺锤体相关的MMDX(MMS19-MIP18-XPD)复合体的亚基。研究表明,FAM96A和FAM96B在人胃肠道间质瘤、结肠癌、肝癌、胃癌和乳腺癌等多种肿瘤组织中的表达显著降低,提示其可能是作为潜在的抑癌基因参与肿瘤的发生发展,但目前关于FAM96A和FAM96B在肿瘤发生发展过程中的作用机理并不十分清楚。此外,研究发现FAM96A和FAM96B可通过与其他不同的蛋白质相互作用在体内发挥多种不同的功能。因此,就目前对于FAM96A和FAM96B结构和功能的研究所取得的进展进行了回顾与总结,并对其在肿瘤发生发展中的分子机制和相互作用蛋白鉴定的研究前景进行了展望,以期为临床上将FAM96A和FAM96B作为新的肿瘤诊断标志物和治疗靶点奠定基础,并为揭示二者在体内更多的新功能提供依据。  相似文献   
85.
[目的]为明确不同太阳能光源波长对松墨天牛Monochamus alternatus诱捕效果的影响,并评价太阳能光源与引诱剂联合应用对松墨天牛引诱剂的促进作用,以应用于松墨天牛的绿色防控.[方法]选择波长为365-370、370-375、380-385、390-395、395-400、400-405、405-420、515-520、580-590和600-610nm的10种太阳能LED光源,测定不同光源对松墨天牛的林间诱捕效果,并筛选出诱捕效果最好的光源波长,选择此波长与引诱剂组合对松墨天牛进行诱捕试验.[结果]10种不同波长太阳能光源对松墨天牛均表现出一定的引诱作用,其中波长为380-385 nm的太阳能光源对松墨天牛诱捕效果最好,诱捕量为(12.00±6.53)头,其次是390-395nm,显著优于波长为365-370、370-375、390-395、395-400、400-405、405-420、515-520、580-590和600-610 nm;与单独使用引诱剂相比,太阳能光源与引诱剂组合对松墨天牛诱捕效果具有显著的促进作用(P<0.05).太阳能光源与引诱剂诱捕量均值为(21.83±10.65)头,比单独引诱剂诱捕效果提高35%,为单独太阳能光源诱捕效果的5.9倍;引诱剂诱、太阳能光源和太阳能光源与引诱剂联合应用捕到的松墨天牛雌雄性比分别为2.4∶1、1.7∶1和3.3∶1,均具有显著的偏雌性.[结论]太阳能光源与引诱剂联合应用具有比单独引诱剂诱捕更好的诱捕效果.这一结论对降低松墨天牛种群密度和减少松材线虫病传播几率具有重要意义.  相似文献   
86.
Anaerobic metabolism and oxygen carrying-capacity of white shrimp (Penaeus vannamei) exposed to short term (three days) and long term (two weeks) moderate hypoxia (2-2.6 mg/L) was investigated. Glucose and lactate levels in hemolymph increased under both hypoxic conditions, indicating an activation of anaerobic pathways during the two-weeks exposure period. In muscle, no differences of glucose and lactate levels were observed between the control group and the exposed groups. In animals exposed to hypoxia for two weeks, hemocyanin and copper in hemolymph were higher than in animals under normoxic conditions or exposed for three days. These results indicate that an increase in oxygen carrying-capacity in shrimp is evident only after a sustained condition of hypoxia. Copper levels in the hepatopancreas decreased in both hypoxic conditions, suggesting a mobilization of copper stores for hemocyanin synthesis. These results indicate that penaeid shrimp can tolerate moderate hypoxic conditions by physiological adaptations, such as anaerobic metabolism and increased oxygen carrying-capacity. These adaptations require an adequate dietary supply of proteins and copper for hemocyanin synthesis and of carbohydrates for anaerobic metabolism.  相似文献   
87.
Several models of activation mechanisms were proposed for G protein-coupled receptors (GPCRs), yet no direct methods exist for their elucidation. The availability of constitutively active mutants has given an opportunity to study active receptor conformations within acceptable limits using models such as the angiotensin II type 1 (AT1)1 receptor mutant N111G-hAT1 which displays an important constitutive activity. Recently, by using methionine proximity assay, we showed for the hAT1 receptor that TMD III, VI, and VII form the ligand-binding pocket of the C-terminal amino acid of an antagonistic AngII analogue. In the present contribution, we investigated whether the same residues would also constitute the ligand-binding contacts in constitutively activated mutant (CAM) receptors. For this purpose, the same Met mutagenesis strategy was carried out on the N111G double mutants. Analysis of 43 receptors mutants in the N111G-hAT1 series, photolabeled and CNBr digested, showed that there were only subtle structural changes between the wt-receptor and its constitutively active form.  相似文献   
88.
Muscarinic activation of tracheal smooth muscle (TSM) involves a M3AChR/heterotrimeric-G protein/NPR-GC coupling mechanism. G protein activators Mastoparan (MAS) and Mastoparan-7 stimulated 4- and 10-fold the NPR-GC respectively, being insensitive to PTX and antibodies against Gαi/o subfamily. Muscarinic and MAS stimulation of NPR-GC was blocked by antibodies against C-terminal of Gαq16, whose expression was confirmed by RT-PCR. However, synthetic peptides from C-terminal of Gαq15/16 stimulated the NPR-GC. Coupling of αq16 to M3AChR is supported by MAS decreased [3H]QNB binding, being abolished after M3AChR-4-DAMP-alkylation. Anti-i3M3AChR antibodies blocked the muscarinic activation of NPR-GC, and synthetic peptide from i3M3AChR (M3P) was more potent than MAS increasing GTPγ [35S] and decreasing the [3H]QNB activities. Coupling between NPR-GC and Gαq16 was evaluated by using trypsin-solubilized-fraction from TSM membranes, which displayed a MAS-sensitive-NPR-GC activity, being immunoprecipitated with anti-Gαq16, also showing an immunoreactive heterotrimeric-G-β -subunit. These data support the existence of a novel transducing cascade, involving Gαq16β γ coupling M3AChR to NPR-GC.  相似文献   
89.
The Maldanidae annelid worms are reviewed and the phylogenetic relationships of their subgroups provided, based on Hennigian principles and maximum parsimony. Characters were coded as binary and multistate (transformation series). We used 33 terminal taxa (species), and 50 characters. Characters were treated as unordered and of equal weight, and analysis was run in TNT. Three equally most-parsimonious trees were obtained with heuristic searches, with lengths of 64 steps; CI = 0.95, and RI = 0.98. The monophyly of Maldanidae was supported with 100% of bootstrap and jackknife values. As a result of our analysis, Arenicolidae remains the sister-group of Maldanidae, and both should be referred to Maldanomorpha. Maldanidae was supported by the following synapomorphies: dorsal prostomium; prostomium keel-shaped and fused to peristomium; torus globose behind median chaetigers; median chaetigers greatly elongated; number of pre-anal segments reduced. The subfamily Bogueinae was not monophyletic; Boguea and Boguella were included within Rhodininae. Clymenura, previously included in the Clymenurinae, was included within Euclymeninae. The taxa Notoproctinae, Maldaninae, Nicomachinae and Euclymeninae were grouped in the Maldanoplaca, a new taxon. Eight further new clades have been found, but were not named.  相似文献   
90.
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