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31.
目的:研究阳春砂小花假合蕊柱的形成过程。方法:将阳春砂小花自0. 5 cm长度至开花后一天划分为8个生长时期,对小花鲜样解剖并制作石蜡切片,测定花药腔的高度,花粉囊裂口夹角,花粉囊缝隙宽度,花柱直径,花丝与唇瓣的夹角(α),花丝与花药的夹角(β)。结果:花粉囊夹角在开花前无明显变化,开花时从32°缩小为17°。两对花粉囊间的缝隙宽度在第5时期增大至约0. 29 mm,同时期的花柱直径约0. 32 mm,两者比例达92%。相比开花前一天,开花时α角从83°减小为42°,β角从186°减小为147°。花丝的远轴侧比近轴侧多1至5层细胞,花柱的近轴侧比远轴侧多1至6层细胞。结论:远、近轴侧细胞结构的不对称性是花丝、花柱运动的基础。在第5时期,花粉囊间的缝隙增大至几乎与花柱等径,花柱运动嵌入花粉囊间。开花时花粉囊夹角缩小,将花粉囊间隙出口封闭,花柱留在花粉囊间,同时角α,β剧烈减小,雄蕊将雌蕊夹在其中向唇瓣弯曲,最终形成半包于唇瓣内的假合蕊柱结构。 相似文献
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BackgroundOsteoarthritis is an age-related disorder of bone-joint that causes pain and disability in middle and older people. This study aimed to investigate the potential effects of long non-coding RNA (lncRNA) THRIL on lipopolysaccharide (LPS)-induced osteoarthritis cell injury model (ATDC5 cell inflammatory injury), as well as the possible internal molecular mechanisms.MethodsCell viability and apoptosis were assessed using CCK-8 assay and Guava Nexin assay, respectively. Cell transfection was conducted to change the expression of THRIL and microRNA-125b (miR-125b) in ATDC5 cells. qRT-PCR was performed to detect the expression of THRIL, miR-125b and pro-inflammatory cytokines IL-6, TNF-α and monocyte chemotactic protein 1 (MCP-1) in ATDC5 cells. ELISA was used to measure the concentrations of IL-6, TNF-α and MCP-1 in culture supernatant of ATDC5 cells. Finally, the protein expression of key factors involved in cell apoptosis, inflammatory response, JAK1/STAT3 and NF-κB pathways were evaluated using western blotting.ResultsLPS significantly induced ATDC5 cell inflammatory injury and up-regulated the expression of THRIL. Overexpression of THRIL aggravated the LPS-induced ATDC5 cell inflammatory injury. Suppression of THRIL had opposite effects. Moreover, THRIL negatively regulated the expression of miR-125b in ATDC5 cells. miR-125b participated in the effects of THRIL overexpression on LPS-induced ATDC5 cell inflammatory injury. Furthermore, overexpression of THRIL enhanced the LPS-induced JAK1/STAT3 and NF-κB pathways activation by down-regulating miR-125b.ConclusionTHRIL exerted pro-inflammatory roles in LPS-induced osteoarthritis cell injury model. Overexpression of THRIL promoted LPS-induced ATDC5 cell inflammatory injury by down-regulating miR-125b and then activating JAK1/STAT3 and NF-κB pathways. 相似文献
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Angiopoietin-like proteins (ANGPTL)-3 and -4 regulate lipid metabolism, but the effect of tree nuts of varying fatty acid composition on post-meal responses is unknown. The purpose of the study was to conduct a secondary analysis of two studies on ANGPTL3 and -4 responses to meals containing different tree nuts. We hypothesized that the pecan-containing meal would mitigate postprandial rises in ANGPTL3 compared to the traditional meal without nuts in males, but not females. In addition, we hypothesized that there would be no other differences between any other treatments in ANGPTL3 or -4 responses. The two studies were double-blind, randomized crossover trials. Twenty-two adults (10=male, 12=female) completed study 1, which compared meals containing pecans vs. no nuts (control), and thirty adults (14=male, 16=female) completed study 2, which compared meals containing black walnuts, English walnuts (EW), or no nuts (control). Blood was collected at fasting, 30, 60, 120, and 180min postprandially. In study 1, ANGPTL3 was suppressed more in pecan vs. control in males (iAUC: -579.4±219.4 vs. -128.4±87.1pg/mL/3h, P<.05). In study 2, there was no difference in ANGPTL3 between black walnuts vs. EW, but ANGPTL3 was suppressed more in control vs. black walnuts in females only (iAUC: -196.4±138.4 vs. 102.1±90.1pg/mL/3h, P<.05). There were no differences in ANGPTL4 between treatments. In conclusion, adding pecans to a meal decreased ANGPTL3 in males, but not females. These data highlight the importance of investigating the impact of nutrients and sex on postprandial ANGPTL3 ad -4 responses to better understand their ability to reduce cardiovascular disease risk. 相似文献
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《Clinical neurophysiology》2009,120(4):754-764
ObjectiveHerein, we report use of electromyography (EMG) to anticipate corticospinal conduction block, as defined by muscle-derived transcranial electrical motor evoked potential (TCE MEP) loss, during extradural spinal cord decompression.MethodsOne hundred and eighty-four patients underwent cervical (173) or thoracic (11) decompression. The same derivations were recorded for EMG and TCE MEP neuromonitoring. When highly repetitive, complex, and prolonged EMG discharges were identified in myotomes below the operated level (severe suprasegmentally-generated EMG discharges = severe SEDs), a report of possible spinal cord impact was made and a TCE MEP obtained. TCE MEP loss (with or without antecedent SEDs) was defined as >90% amplitude reduction compared to baseline recordings.ResultsSevere SEDs, seen in 15 cases, anticipated TCE MEP loss in 7/15. In 13/15 severe SED cases, manipulations near dura were the proximate cause. Interventions after TCE MEP loss included changed instrumentation, re-positioning, increased blood pressure, wake-up test, and surgical pause.ConclusionsSEDs can be identified during extradural spinal cord decompression. Severe SED occurrence is associated with a ∼50% risk of subsequent corticospinal conduction block.SignificanceAlthough SED occurrence does not provide specific information for lesions of the fast neurons of the corticospinal tract, SED surveillance during decompression at spinal cord level can supplement TCE MEP recording. 相似文献
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There are invasive and noninvasive pulmonary function tests available which are sensitive in detecting bronchoconstriction in rodents. Noninvasively measured midexpiratory flow (EF50) has been shown to be an appropriate parameter to monitor bronchoconstriction in a large number of animals, e.g. for screening purposes.Recently, a novel technique for repetitive lung function measurements in orotracheally intubated, spontaneously breathing mice has been established. Bronchoconstriction is assessed by the “gold standard” parameters airway resistance and dynamic compliance in response to aerosolized methacholine or allergens in anesthetized mice. This measurement technique has been combined with an inhalation technique which has been optimized to allow simultaneous lung function measurement in intubated animals and to obtain high aerosol concentrations. A feedback dose control system has been developed to administer a defined and constant aerosol dose to each individual animal. Using this system a prominent early allergic response and late airway hyperresponsiveness could be demonstrated in intubated mice challenged with Aspergillus fumigatus allergen.We conclude: The noninvasive EF50 method seems particularly appropriate for measurements of respiratory function in large numbers of conscious mice in assembly line fashion. The invasive technology – newly established for the mouse – is more sensitive and specific since true airway resistance and dynamic compliance are determined and allows now the adequate detection of an early allergic response in the mouse and also repetitive measurements e.g. to assess the airway hyperresponsiveness in the same animal or for monitoring purposes in chronic models. 相似文献
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