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591.
歧口凹陷沿岸带新生代构造特征及其形成机制 总被引:6,自引:0,他引:6
歧口凹陷沿岸带是一条分隔歧口凹陷陆上和海域不同构造体系的NNE-NE的复杂构造变形带。在其两侧,盆地结构分别表现为半地堑和地堑式。在平面上,自南向北歧口凹陷沿岸带可以分为三个具有明显不同的新生代构造变形组合特征的区段:南部的斜列式走滑变形带,体现为一系列阶梯状展布的张扭断层,同时伴有岩浆活动和滑塌浊积体发育;中部的宽缓挠曲变形带,构造样式简单,地层只有微弱变形,但仍然伴随强烈的火山活动;北部的复杂断裂褶皱带是受基底走滑断层影响而形成的古近纪重力滑脱断层和新近纪花状构造的有机结合体。总体上,沿岸带复杂的构造组合特征是受到深部向北隐没的新生代右旋基底走滑断裂活动的控制,是渤海湾盆地内兰聊断裂通过歧口凹陷时的构造表现。歧口凹陷沿岸带在不同区段的构造变形特征,也造成了不同区段的油气成藏模式的差异性。 相似文献
592.
The present study evaluated the neurogenesis of neonatal valproic acid (VPA) exposure on subventricular zone progenitors of the developing cerebral cortex in ferrets. VPA was injected at a dose of 200 µg/g of body weight into ferret infants on postnatal days 6 and 7. Two different thymidine analogues, 5-ethynyl-2′-deoxyuridine (EdU) and 5-bromo-2′-deoxyuridine (BrdU), were injected with a 48 h interval to label proliferating cells before and after VPA exposure. Two hours after BrdU injection, BrdU single- and EdU/BrdU double-labeled cells, but not EdU single-labeled cells, were significantly denser in both the inner and outer subventricular zones of VPA-exposed infants than in control infants. Notably, more than 97% of BrdU single- and EdU/BrdU double-labeled cells were immunopositive for Pax6, a stable marker for basal radial glia (bRG), in both groups. In contrast, the percentage of cells positively immunostained for Cux1, a postmitotic marker for upper-layer cortical neurons, in both EdU single- and BrdU single-labeled cells, was significantly higher in VPA-exposed infants than in control infants. These findings suggest that neonatal VPA exposure facilitates bRG proliferation, including self-renewal, followed by their differentiation into upper layer cortical neurons in the premature cortex of ferrets. 相似文献
593.
Maria Tsivilika Dimitrios Kavvadas Sofia Karachrysafi Katerina Kotzampassi Vasilis Grosomanidis Eleni Doumaki Soultana Meditskou Antonia Sioga Theodora Papamitsou 《International journal of molecular sciences》2022,23(11)
Background: This study aims to investigate the probable lesions and injuries induced in the renal tissue after a cardiac arrest. The renal ischemia–reperfusion model in cardiac arrest describes the effects of ischemia in the kidneys, alongside a whole-body ischemia–reperfusion injury. This protocol excludes ischemic conditions caused by surgical vascular manipulation, venous injury or venous congestion. Methods: For the experimental study, 24 swine were subjected to cardiac arrest. Seven minutes later, the cardiopulmonary resuscitation technique was performed for 5 min. Afterwards, advanced life support was provided. The resuscitated swine consisted one group and the non-resuscitated the other. Tissue samples were obtained from both groups for light and electron microscopy evaluation. Results: Tissue lesions were observed in the tubules, parallel to destruction of the microvilli, reduction in the basal membrane invaginations, enlarged mitochondria, cellular vacuolization, cellular apoptosis and disorganization. In addition, fusion of the podocytes, destruction of the Bowman’s capsule parietal epithelium and abnormal peripheral urinary space was observed. The damage appeared more extensive in the non-resuscitated swine group. Conclusions: Acute kidney injury is not the leading cause of death after cardiac arrest. However, evidence suggests that the kidney damage after a cardiac arrest should be highly considered in the prognosis of the patients’ health outcome. 相似文献
594.
传统支持向量机由两类扩展到多类问题时,会出现不可分区域。针对这种情况,在传统支持向量机中引入模糊隶属度函数,用模糊支持向量机(FSVM)解决了传统支持向量机在多类识别中的盲区问题。实验表明,该方法在进行皮肤色素斑症状的识别过程中效率较传统支持向量机明显提高。 相似文献
595.
The present experiments used 2 versions of a modified Hebb-Williams maze to test the role of the dorsal hippocampus (dHip) and parietal cortex (PC) in processing allocentric and egocentric space during acquisition and retention. Bilateral lesions were made to either the dHip or PC before maze testing (acquisition) or after maze testing (retention). The results indicate that lesions of the dHip impair allocentric maze acquisition, whereas lesions of the PC impair egocentric maze acquisition. During retention, lesions of the PC produced a significant impairment on both maze versions, whereas lesions of the dHip produced short-lived, transient impairments on both maze versions. These results suggest that during acquisition, the hippocampus and PC process spatial information in parallel; however, long-term retention of spatial information requires the PC with the dHIP as necessary for retrieval and/or access but not necessarily storage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
596.
Olesen Pernille J.; Schendan Haline E.; Amick Melissa M.; Cronin-Golomb Alice 《Canadian Metallurgical Quarterly》2007,121(6):1163
Human immunodeficiency virus (HIV) in the asymptomatic phase of the infection impairs some aspects of cognition, but little is known about how visuospatial functions are affected. In the present study, performance on tasks of mental rotation and hierarchical pattern perception was investigated in 14 HIV-positive men and 12 age- and education-matched HIV-negative men. Processes related to mental rotation of objects and hands were impaired in HIV-positive participants as compared to the HIV-negative group. The HIV-positive group was also impaired on hierarchical pattern perception of local targets under global biasing conditions. Consistent with these results, the HIV-positive participants showed impaired performance on standard clinical neuropsychological tests of visuospatial function. These findings indicate that the detrimental effects of HIV on cognition appear even in asymptomatic individuals and affect diverse visuospatial functions that depend upon the integrity of parietal brain regions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
597.
Marianna Fabi Biljana Petrovic Laura Andreozzi Elena Corinaldesi Emanuele Filice Carlotta Biagi Alessia Rizzello Bianca Elisa Mattesini Simone Bugani Marcello Lanari 《International journal of molecular sciences》2022,23(17)
Background: Kawasaki Disease (KD) and Multisystem Inflammatory Syndrome in Children (MIS-C) are pediatric diseases characterized by systemic inflammation and vascular injury, potentially leading to coronary artery lesions (CALs). Data on vascular injury occurring during acute COVID-19 (AC19) in children are still lacking. The aim of our study was to investigate endothelial injury in KD-, MIS-C- and AC19-dosing circulating endothelial cells (CECs). Methods: We conducted a multicenter prospective study. CECs were enumerated by CellSearch technology through the immunomagnetic capture of CD146-positive cells from whole blood. Results: We enrolled 9 KD, 20 MIS-C and 10 AC19. During the acute stage, the AC19 and KD patients had higher CECs levels than the MIS-C patients. From the acute to subacute phase, a significant CEC increase was observed in the KD patients, while a mild decrease was detected in the MIS-C patients. Cellular clusters/syncytia were more common in the KD patients. No correlation between CECs and CALs were found in the MIS-C patients. The incidence of CALs in the KD group was too low to investigate this correlation. Conclusions: Our study suggests a possible role of CECs as biomarkers of systemic inflammation and endothelial dysfunction in KD and MIS-C and different mechanisms of vascular injury in these diseases. Further larger studies are needed. 相似文献
598.
599.
Salwan Tajjour Sonia Garg Shyam Singh Chandel Diksha Sharma 《International journal of imaging systems and technology》2023,33(1):276-286
In this study, an innovative hybrid machine learning-technique is used for the early skin cancer diagnosis fusing Convolutional Neural Network and Multilayer Perceptron to analyze images and information related to the skin cancer. This information is extracted manually after applying different color space conversions on the original images for better screening of the lesions. The proposed architecture is compared with standalone architecture in addition to some other techniques by commonly used evaluation metrics. HAM10000 dataset is used for training and testing as this data contain seven different skin lesions. The novelty of the proposed hybrid model is the structure of the network which handles structured data (patients' metadata and other useful features from different color spaces related to the illumination, energy, darkness, etc.) and unstructured data (images). The results show an overall 86%, 95% top-1 and top-2 accuracy respectively, and 96% area under the curve for the seven classes. The study demonstrates the superiority of the proposed hybrid model with a 2% improvement in the accuracy over the standalone model and a promising behavior as compared to the ensemble techniques. The follow-up research will include more patient data to develop a skin cancer detection device. 相似文献
600.
《Journal of dairy science》2023,106(4):2667-2684
Sole hemorrhage and sole ulcers, referred to as sole lesions, are important causes of lameness in dairy cattle. We aimed to compare the serum metabolome of dairy cows that developed sole lesions in early lactation with that of cows that remained unaffected. We prospectively enrolled a cohort of 1,169 Holstein dairy cows from a single dairy herd and assessed animals at 4 time points: before calving, immediately after calving, early lactation, and late lactation. Sole lesions were recorded by veterinary surgeons at each time point, and serum samples were collected at the first 3 time points. Cases were defined by the presence of sole lesions in early lactation and further subdivided by whether sole lesions had been previously recorded; unaffected controls were randomly selected to match cases. Serum samples from a case-control subset of 228 animals were analyzed with proton nuclear magnetic resonance spectroscopy. Spectral signals, corresponding to 34 provisionally annotated metabolites and 51 unlabeled metabolites, were analyzed in subsets relating to time point, parity cohort, and sole lesion outcome. We used 3 analytic methods (partial least squares discriminant analysis, least absolute shrinkage and selection operator regression, and random forest) to determine the predictive capacity of the serum metabolome and identify informative metabolites. We applied bootstrapped selection stability, triangulation, and permutation to support the inference of variable selection. The average balanced accuracy of class prediction ranged from 50 to 62% depending on the subset. Across all 17 subsets, 20 variables had a high probability of being informative; those with the strongest evidence of being associated with sole lesions corresponded to phenylalanine and 4 unlabeled metabolites. We conclude that the serum metabolome, as characterized by proton nuclear magnetic resonance spectroscopy, does not appear able to predict sole lesion presence or future development of lesions. A small number of metabolites may be associated with sole lesions although, given the poor prediction accuracies, these metabolites are likely to explain only a small proportion of the differences between affected and unaffected animals. Future metabolomic studies may reveal underlying metabolic mechanisms of sole lesion etiopathogenesis in dairy cows; however, the experimental design and analysis need to effectively control for interanimal and extraneous sources of spectral variation. 相似文献