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991.
本研究采用公里网格抽样方案, 在广东鼎湖山国家级自然保护区及其周边林地(烂柯山省级自然保护区和小湘林区)选取3个监测样地, 共设置60个红外相机监测位点, 对区域内大中型兽类和地面活动鸟类开展物种编目清查与评估。2017年1月至2018年12月, 红外相机累计工作34,212个相机日, 共获得独立有效照片11,725份。共记录到75种野生动物, 隶属于13目32科63属, 包括兽类12种、鸟类63种, 其中国家一级重点保护动物有1种, 即中华穿山甲(Manis pentadactyla), 国家二级重点保护动物有9种。兽类中相对多度指数排前三的依次为野猪(Sus scrofa)、鼬獾(Melogale moschata)和赤麂(Muntiacus vaginalis); 鸟类依次为白鹇(Lophura nycthemera)、橙头地鸫(Geokichla citrina)和紫啸鸫(Myophonus caeruleus)。三个监测样地的相对多度指数排前三的物种基本一致, 其中鼎湖山的白鹇相对多度指数最高; 小湘的豹猫(Prionailurus bengalensis)相对多度指数位列第三, 仅次于野猪和鼬獾; 烂柯山相对多度指数排前三的鸟类则依次为画眉(Garrulax canorus)、灰胸竹鸡(Bambusicola thoracicus)和红嘴相思鸟(Leiothrix lutea)。本研究为广东鼎湖山及其周边林地生物多样性监测与评估提供了数据参考。  相似文献   
992.
目的:探讨Kallistatin在乳腺癌中表达的临床病理意义及预后价值。方法:收集乳腺癌档案蜡块及临床资料,分为无淋巴结转移的原发灶(NMBT),有淋巴结转移的原发灶(PBT)及配对的淋巴结转移灶(PMLN),应用免疫组化技术检测Kallistatin表达,统计学分析。结果:结果显示kallistatin在PBT组的表达高于NMBT组合和PMLN组。kallistatin的表达与组织学类型(P=0.003)、淋巴结状态(P0.001)、临床分期(P=0.002)、雌激素受体(ER)表达(P=0.046)有显著相关性。kallistatin在浸润性小叶癌中的阳性表达率高于浸润性导管癌,在PBT组的阳性表达率显著高于NMBT,临床分期越晚期阳性表达率越高,在ER阳性的病历中表达更高。Kaplan-Meier分析显示,kallistatin的阳性表达是乳腺癌患者无病生存时间短(P=0.008)和总生存时间短(P=0.006)的危险因素。在浸润性乳腺导管癌患者中,kallistatin的阳性表达与生存时间短有关(P=0.026)。还与ER阳性表达患者生存时间较短有关(P=0.010)。结论:Kallistatin在乳腺癌中的表达有较为复杂的临床病理意义,其表达提示预后不良。  相似文献   
993.
目的:分析小儿消化性疾病的胃电图变化及与临床病理特征和胃镜特征的关联性。方法:选取2018年1月至2019年5月我院儿科收治的经胃镜和病理学两种方式诊断为消化性疾病的患儿54例为观察组,另选取无胃肠道疾病的健康儿童40例为对照组。比较两组胃电图参数(频率均值和波幅均值),54例胃电图诊断后纤维胃镜检查结果,分析消化性疾病患儿HP感染与临床病理特征、溃疡面积的关系。结果:各组胃病患者胃电慢波频率均值各不相同(P0.05),三组患者胃电慢波波幅均值相比差异具有统计学意义(P0.05);且浅表性胃炎组、胆汁反流性胃炎组患者胃电慢波频率均值、胃电慢波波幅均显著低于胃溃疡组(P0.05);浅表性胃炎组患者胃电慢波频率均值显著低于胆汁反流性胃炎组(P0.05)。胆汁反流性胃炎组患者胃电慢波波幅显著低于浅表性胃炎组(P0.05)。胃镜检查结果显示,其中浅表性胃炎的诊断符合率较高,达90.00%,胃溃疡符合率为60.71%,胆汁反流性胃炎符合率为83.33%。HP检测结果显示,HP阳性患儿占总例数的77.78%(42/54),HP阴性患儿占总例数的22.22%(12/54);HP阳性组患儿淋巴滤泡形成、胃黏膜萎缩、胃黏膜炎性活动的发生率明显高于HP阴性组,差异具有统计学意义(P0.01);HP阳性组溃疡范围2 cm的患儿比例明显高于HP阴性患儿,差异具有统计学意义(P0.01)。结论:小儿消化性疾病胃电图存在餐后NSWP的下降及节律过缓的上升,胃电图检查和胃镜检查在诊断上有较高的符合率,HP感染科引起胃黏膜组织学改变,可作为小儿消化性疾病的靶向治疗。  相似文献   
994.
张利平  薛燕  郭翔  王明田 《应用生态学报》2020,31(11):3823-3832
利用数字高程模型(DEM)数据、土地覆盖栅格数据、四川省52个站点和4个其他省市站点的气象观测数据,基于美味牛肝菌的生物学特性,结合前人研究成果,系统分析了川西高原山地美味牛肝菌的气候生态适宜性。选取气温、降水、植被等影响因子作为区划指标,应用集优法,通过GIS分析本区美味牛肝菌资源的潜在分布。结果表明: 美味牛肝菌潜在分布区的北界在32° N附近,海拔上限约为3000 m,下限约为800 m,总面积约286.3万hm2,约占研究区整个行政区域面积的9.7%;29° N以南的攀西地区是美味牛肝菌的主要潜在分布区,核心分布区在攀西地区中南部,攀西分布区面积约占全部潜在分布区的90%,其中,适宜区面积约占20%,次适宜面积约占80%。适宜区主要分布于攀西地区雅砻江以东的安宁河流域、海拔1000~2600 m的山区;次适宜区主要是适宜区分别向上、向下延伸到海拔3000和800 m左右的林区;海拔3000 m以上的高原高山区和海拔800 m以下的干热河谷区为不适宜区。  相似文献   
995.
Break-induced replication (BIR) is essential for the repair of DNA double-strand breaks (DSBs) with single ends. DSBs-induced microhomology-mediated BIR (mmBIR) and template-switching can increase the risk of complex genome rearrangement. In addition, DSBs can also induce the multi-invasion-mediated DSB amplification. The mmBIR-induced genomic rearrangement has been identified in cancer cells and patients with rare diseases. However, when and how mmBIR is initiated have not been fully and deeply studied. Furthermore, it is not well understood about the conditions for initiation of multi-invasion-mediated DSB amplification. In the G2 phase oocyte of mouse, we identified a type of short-scale BIR (ssBIR) using the DNA replication indicator 5-ethynyl-2’-deoxyuridine (EdU). These ssBIRs could only be induced in the fully grown oocytes but not the growing oocytes. If the DSB oocytes were treated with Rad51 or Chek1/2 inhibitors, both EdU signals and DSB marker γH2A.X foci would decrease. In addition, the DNA polymerase inhibitor Aphidicolin could inhibit the ssBIR and another inhibitor ddATP could reduce the number of γH2A.X foci in the DSB oocytes. In conclusion, our results showed that DNA DSBs in the fully grown oocytes can initiate ssBIR and be amplified by Rad51 or DNA replication.  相似文献   
996.
以伊犁南部山区雪岭云杉风倒木为对象,研究了1.3、5、10、15、20 m树高处树轮圆盘样品的最大密度、最小密度、早材平均密度、晚材平均密度4种树轮密度年表,结合当地气象观测资料进行相关分析,研究树干不同高度树轮密度对气候要素的响应特征。结果表明: 同一树高下4种密度参数在整体上表现出较高的相关性,其中10、15、20 m树高相对显著;不同树高处晚材平均密度的一致性相对较好;不同树高处树轮密度对气候要素的响应存在差异,15 m树高处最大密度、晚材平均密度对上年7—9月、当年5—9月平均气温具有较好的响应。因此,在1.3 m处采集雪岭云杉样本存在对气温响应估计偏低的可能。  相似文献   
997.
Background: Angiogenesis and inflammation are implicated in breast cancer prognosis; however, the role of individual germline variation in related genes is unknown. Methods: A two-stage candidate pathway association study was conducted among 6983 Chinese women. Stage 1 included 2884 women followed for a median of 5.7 years; Stage 2 included 4099 women followed for a median of 4.0 years. Cox proportional hazards regression was used to estimate the effects of genetic variants on disease-free survival (DFS) and overall survival (OS). Results: Stage 1 included genotyping of 506 variants in 22 genes; analysis was conducted for 370 common variants. Nominally significant associations with DFS and/or OS were found for 20 loci in ten genes in Stage 1; variants in 19 loci were successfully genotyped and evaluated in Stage 2. In analyses of both study stages combined, nominally significant associations were found for nine variants in seven genes; none of these associations surpassed a significance threshold level corrected for the total number of variants evaluated in this study. Conclusions: No association with survival was found for 370 common variants in 22 angiogenesis and inflammation pathway genes among Chinese women with breast cancer. Impact: Our data do not support a large role for common genetic variation in 22 genes in breast cancer prognosis; research on angiogenesis and inflammation genes should focus on common variation in other genes, rare host variants, or tumor alterations.  相似文献   
998.

Objectives

To monitor intra-abdominal pressure (IAP) and intestinal barrier function in a rat model of acute necrotizing pancreatitis (ANP) to elucidate a potential relevant therapeutic window.

Methods

Sprague-Dawley rats were randomly divided into experimental or control groups. The ANP group (n = 40) was injected with 4.5% sodium taurocholate into the pancreatic duct to induce ANP. The controls received only abdominal opening surgery (sham-operated, SO; n = 40) or no treatment or surgery (baseline; 0 h, n = 20). The SO and ANP groups were then randomly subdivided into 3, 6, 12 and 24 h groups (n = 10 each). IAP was measured at each time point and the rats were sacrificed to measure the weight of accumulated ascites fluid and the amylase, endogenous creatinine (Cr), total bilirubin (TB), tumor necrosis factor- alpha (TNF-alpha), diamine oxidase (DAO), and D-lactate. Mortality and the development of pathological changes in the pancreas and intestines were also monitored.

Results

IAP showed a continuous upward trend in the ANP group, with values 2 to 3 times higher than those in the SO group at the corresponding time points and the rising rate was peaking at 6 h. The levels of plasma amylase, TNF-alpha, Cr, TB, DAO, and D-lactate also gradually increased in the ANP group over time and were significantly higher than in the SO group at 3, 6, 12 and 24 h (all P<0.05). Moreover, the rising rate of TNF-alpha, DAO, and D-lactate also peaked at 6 h.

Conclusions

The ANP-induced changes in IAP, inflammatory factors and intestinal barrier that we observed in the rat model were especially obvious at 6 h post-induction, suggesting an early therapeutic window for the treatment of ANP in humans.  相似文献   
999.

Objectives

To determine whether or not the antioxidants N-acetylcysteine (NAC) and allopurinol (ALP) confer synergistic cardioprotection against myocardial ischemia/reperfusion (MI/R) injury by stabilizing hypoxia inducible factor 1α (HIF-1α)/heme oxygenase 1 (HO-1) signaling in diabetic myocardium.

Methods

Control or diabetic [streptozotocin (STZ)-induced] Sprague Dawley rats received vehicle or NAC, ALP or their combination for four weeks starting one week after STZ injection. The animals were then subjected to thirty minutes of coronary artery occlusion followed by two hours reperfusion in the absence or presence of the selective HO-1 inhibitor, tin protoporphyrin-IX (SnPP-IX) or the HIF-1α inhibitor 2-Methoxyestradiol (2ME2). Cardiomyocytes exposed to high glucose were subjected to hypoxia/re-oxygenation in the presence or absence of HIF-1α and HO-1 achieved by gene knock-down with related siRNAs.

Results

Myocardial and plasma levels of 15-F2t-isoprostane, an index of oxidative stress, were significantly increased in diabetic rats while cardiac HO-1 protein and activity were reduced; this was accompanied with reduced cardiac protein levels of HIF-1α, and increased post-ischemic myocardial infarct size and cellular injury. NAC and ALP given alone and in particular their combination normalized cardiac levels of HO-1 and HIF-1α protein expression and prevented the increase in 15-F2t-isoprostane, resulting in significantly attenuated post-ischemic myocardial infarction. NAC and ALP also attenuated high glucose-induced post-hypoxic cardiomyocyte death in vitro. However, all the above protective effects of NAC and ALP were cancelled either by inhibition of HO-1 or HIF-1α with SnPP-IX and 2ME2 in vivo or by HO-1 or HIF-1α gene knock-down in vitro.

Conclusion

NAC and ALP confer synergistic cardioprotection in diabetes via restoration of cardiac HIF-1α and HO-1 signaling.  相似文献   
1000.
Elevation of serum IgE levels has long been associated with allergic diseases. Many genes have been linked to IgE production, but few have been linked to the developmental aspects of genetic association with IgE production. To clarify developmental genetic association, we investigated what genes and gene-gene interactions affect IgE levels among fetus, infancy and childhood in Taiwan individuals. A birth cohort of 571 children with completion of IgE measurements from newborn to 1.5, 3, and 6 years of age was subject to genetic association analysis on the 384-customized SNPs of 159 allergy candidate genes. Fifty-three SNPs in 37 genes on innate and adaptive immunity, and stress and response were associated with IgE production. Polymorphisms of the IL13, and the HLA-DPA1 and HLA-DQA1 were, respectively, the most significantly associated with the IgE production at newborn and 6 years of age. Analyses of gene-gene interactions indentified that the combination of NPSR1, rs324981 TT with FGF1, rs2282797 CC had the highest risk (85.7%) of IgE elevation at 1.5 years of age (P = 1.46×10−4). The combination of IL13, CYFIP2 and PDE2A was significantly associated with IgE elevation at 3 years of age (P = 5.98×10−7), and the combination of CLEC2D, COLEC11 and CCL2 was significantly associated with IgE elevation at 6 years of age (P = 6.65×10−7). Our study showed that the genetic association profiles of the IgE production among fetus, infancy and childhood are different. Genetic markers for early prediction and prevention of allergic sensitization may rely on age-based genetic association profiles.  相似文献   
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