GIS支持下1985-2000年北京林地数量、质量演变与驱动分析

在收集、研究1985年、1995年、2000年北京土地覆盖类型的图像和矢量数据的基础上,提取不同时间段北京林地相关的数据信息,并从多个角度分析研究区内各类林地与其它土地覆盖类型之问相互转化和各类林地之间的演替情况,得出2000年北京各类林地面积总量与1985年相比有少量增加,但林地总体质量水平却有下降趋势;并从经济社会发展以及国家及北京的生态环保政策等方面,对林地演变的驱动因子进行分析.     

生物结皮对高寒退化草地植物群落的影响

生物结皮在各类生态系统中扮演着重要的角色,具有调控土壤水分,养分含量与侵蚀敏感性等作用,并可直接或间接地影响地上植物群落,但对植物群落发展存在促进还是抑制作用尚不清楚。本研究于2017年在青海贵南县森多镇高寒草原,设置大样方,对生物结皮种类和分布格局进行调查。结果表明：在青藏高原高寒退化草地生态系统中,生物结皮的存在显著影响了植物的群落结构,降低了杂草的比例;苔藓生物结皮的盖度与草本植物盖度在初级发育阶段的生物结皮（地衣和苔藓共存）的样方中呈显著正相关关系（P<0.05）,在高级发育阶段的生物结皮（仅有苔藓结皮存在）的样方中正相关关系极显著（P<0.01）。由此可见,生物结皮是高寒草地生态系统的重要组成部分,有调节高寒退化植物群落的结构和功能的作用。     

Epidemiological Description of Cystic Ovarian Disease in Argentine Dairy Herds: Risk Factors and Effects on the Reproductive Performance of Lactating Cows

To describe the epidemiology of cystic ovarian disease (COD), to find possible risk factors associated with the incidence of cysts and to analyse the impact of COD on the reproductive performance of dairy cows, databases from 22 dairy herds from the main dairy region in Argentina were retrospectively evaluated throughout a 3‐year period (2009–2011). A total of 248 COD cases over 9156 parturitions were recorded, resulting in a cumulative incidence rate of 2.7%. Cystic ovarian disease incidence density was lower during the first 100 days post‐partum (DPP) than during later stages of lactation. Seasonality had a significant influence on the disease presentation with higher incidence rates during winter and spring. Cows with a previous diagnosis of clinical mastitis showed 2.72 times more chances of developing ovarian cysts. Cystic cows had longer calving to first service and calving to conception intervals and lower conception rate than controls.     

玉树州特色中藏药发展对策及前景分析

根据玉树特殊的地理环境,气候特点,特色中藏药自然资源优势及其形态特征,提出了玉树特色中藏药发展对策。     

施肥与灌水对硝态氮在土壤中残留的影响

通过田间试验研究不同施氮量与灌水量对春玉米和冬小麦田土壤中硝态氮分布与累积的影响,结果表明,春玉米收获后0~2 m土壤中累积硝态氮185.7~748.0 kg/hm2,其中1 m以上占57.9%~70.1%。由于施用氮肥而增加的硝态氮占施N量的1.8%(N 112.5 kg/hm2),50.7%(N 225 kg/hm2),56.7%(N 337.5 kg/hm2)和77.0%(N450 kg/hm2)。不施N和施N 112.5 kg/hm2时春玉米田土壤剖面没有明显累积峰;施N等于或高于225 kg/hm2时在60~80 cm土层有明显累积峰,施氮量高的峰值较高;施N 450 kg/hm2时在120~140 cm深度出现另一个累积高峰。冬小麦收获后土壤0~2 m硝态氮累积量为74.9~328.8 kg/hm2,其中1m以上占67.8%~90.7%。由于施用氮肥而增加的硝态氮占施N量的19.5%(N 112.5 kg/hm2),35.6%(N 225 kg/hm2),58.9%(N 337.5 kg/hm2)和56.4%(N 450 kg/hm2)。冬小麦田收获后土壤深层(1~2 m)没有明显的硝态氮累积,即使施氮量高达450 kg/hm2时也只在表层40 cm以上累积较多。不论是春玉米还是冬小麦,当生育期施氮量大于225 kg/hm2时0~2 m土层均有明显的硝态氮累积,施氮量高的累积量较高。施氮量是造成土壤中硝酸盐累积的主要因素,灌水量对春玉米田硝态氮的向下迁移有显著影响。     

低温在诱导油桃芽解除休眠过程中对代谢的影响

果树温室栽培时常出现萌芽率低，萌芽开花延迟，花器官发育差，座果率低等问题。调查了分批移入人工气候室的“NJ72”油桃萌芽率，以确定其休眠解除时间，试验结果表明“NJ72”油桃于1月中旬结束休眠，不同温度处理对“NJ72”油桃休眠期代谢的影响不同，低温促进花芽内H2O2的积累，同时促进过氧化氢酶（CAT）、超氧物歧化酶（SOD）、过氧化物酶（POD）活性的提高，低温处理使花芽呼吸速率增加，其中磷酸戊糖途径（PPP）代谢增加，糖酵解（EMP）降低，而三羧酸循环（TCA）代谢波动较小，葡萄糖－6－磷酸（G－6－PDH）脱氢酶活性也有所增加。     

茵山莲水提物对四氯化碳诱导小鼠急性肝损伤的保护作用

为探讨茵山莲水提物对四氯化碳(CCl₄)诱导的小鼠急性肝损伤的保护作用及可能机制,以对后续茵山莲的深入研究及临床转化提供理论指导。将60只ICR小鼠随机分为6组,每组10只,分别为空白对照组、模型对照组、联苯双酯对照组、茵山莲低(1.17 mg·g^-1)、中(2.34 mg·g^-1)、高(4.68 mg·g^-1)剂量组,按不同剂量药物每天灌胃1次,给药7 d。在末次给药1 h后,除空白对照组以外,其余各组小鼠腹腔注射0.2%四氯化碳构建急性肝损伤模型。12 h后小鼠眼球采血并分离血清,收集肝组织。采用生化分析检测血清总蛋白(TP)和谷胱甘肽S转移酶(GST)活性,肝组织中GST、琥珀酸脱氢酶(SDH)、过氧化氢酶(CAT)和总超氧化物歧化酶(T-SOD)活性,利用HE染色和Masson染色观察肝组织病理及肝纤维化情况,采用蛋白免疫印迹法和免疫组织化学法检测肝组织白介素1beta (IL-1β)、肿瘤坏死因子alpha (TNF-α)、血管生成因子A (VEGFA),金属基质蛋白酶9(MMP9)及转录因子NF-κBp65、蛋白激酶IKK、p38MAPK等蛋白表达及定位情况。结果表明,与模型对照组相比,2.34 mg·g^-1茵山莲水提物能显著降低小鼠血清GST水平,显著升高肝内CAT水平,各组间T-SOD无显著差异,但2.34 mg·g^-1茵山莲水提物组小鼠与空白对照组、模型对照组在肝GST、SDH和血清TP水平上无显著差异。2.34 mg·g^-1茵山莲水提物能缓解CCl₄诱导的小鼠肝病理损伤和纤维化病变,抑制肝IL-1β、TNF-α、VEGFA、NF-κBp65和IKK的表达。提示茵山莲水提物可能通过NF-κB和p38MAPK通路抑制肝氧化应激和炎症水平,从而缓解小鼠急性肝损伤。     

腹腔注射N-甲基-D-天冬氨酸对母鼠发情率、早期胚胎及胚子数的影响

为研究腹腔注射N-甲基-D-天冬氨酸(NMDA)对母鼠发情率和早期胚胎及胚子数的影响,试验选取40只昆明小鼠[(26±1.37)g],随机分为对照组和试验组(每组各20只),对照组腹腔注射0.2mL生理盐水,试验组腹腔注射0.2mLNMDA溶液,采用棉签蘸取母鼠阴道黏液,涂片后用苏木精(HE)染色,判定母鼠发情情况。随后在发情母鼠与公鼠合笼后第3天,每组随机取10只颈椎脱臼法处死小鼠,冲胚后在体视镜下捡胚观察胚胎个数;第9天处死剩余小鼠,取出子宫统计胚子数。试验结果显示,腹腔注射NMDA试验组母鼠发情率、胚胎数和胚子数分别比对照组提高28.57%、18.18%和12.94%。该试验表明腹腔注射NMDA可促进母鼠的发情,提高早期胚胎和胚子数,为NMDA在动物繁殖中的应用提供了理论基础。     

Follicle Turnover and Pregnancy Rates Following Oestrus Synchronization Protocols in Mediterranean Italian Buffaloes (Bubalus bubalis)

An ultrasound assessment of follicle turnover following two different protocols for synchronization of oestrus and ovulation, as well as an assessment of achieved synchronization between ovulation and AI and conception rates in nulliparous and pluriparous buffaloes were carried out during months of increasing day length. Nulliparous buffaloes (n = 30) were subjected only to Ovsynch protocol whereas pluriparous buffaloes (n = 31) were assigned to Ovsynch (n = 14) or to PRID-pregnant mare serum gonadotrophin (PMSG) (n = 17) protocol according to the presence of functional CL confirming cyclic and acyclic conditions. Ultrasound examination of ovarian follicular dynamics at critical days in the course of synchronization treatments was employed to monitor the fate of the largest available follicles at the beginning of treatments. Such available dominant follicle would persist throughout the protocol as ovulating follicle (no-follicle shift) or would regress giving way to a new follicle to become dominant and ovulate (follicle shift). Furthermore, ultrasound monitoring would determine the degree of synchronization of ovulation and final outcome represented by pregnancy rates. Pregnancy rate following Ovsynch protocol was 40% (12/30) and 42.8% (6/14) in nulliparous and pluriparous buffaloes respectively (p = 0.8575). Most ovulations were synchronized and recorded at AI and the following day in nulliparous (24/30; 80%) and pluriparous (12/14; 85.7%) buffaloes respectively (p = 1.000). A follicle shift was recorded in 14 of 30 (46.6%) and 11 of 14 (78.5%) in nulliparous and pluriparous buffaloes respectively (p = 0.0466). Among established pregnancies: eight derived from follicle shift (66.6%) and four from no-follicle shift (33.3%) in nulliparous buffaloes, p = 0.0729 whereas in pluriparous buffaloes five (83.3%) derived from follicle shift and one from no-follicle shift (16.6%), p = 0.6154. Collectively, from 18 pregnancies in nulliparous and pluriparous buffaloes following Ovsynch protocol, 13 derived from follicle shift (72.2%) and five from no-follicle shift (27.7%), p = 0.0860. Pregnancy rate in pluriparous buffaloes following PRID-PMSG protocol was 70.5% (12/17). The majority of ovulations were synchronized and recorded at first, second AI and following day (13/17; 76.4%). A follicle shift occurred in 15/17 buffaloes (88.2%) and among the 12 recorded pregnancies, 11 derived from follicle shift (91.6%), p = 0.5147. In conclusion, pregnancy rates following Ovsynch protocol were similar in nulliparous and pluriparous cyclic buffaloes. A progestagen treatment on acyclic buffaloes but still displaying some ovarian follicular dynamics, resulted in significantly higher pregnancy rate compared with Ovsynch (p = 0.0376). According to the time of scheduled AI, a high degree of synchronized ovulations were recorded following the implementation of both protocols.     

原子吸收分光光度法测定植物中微量元素的研究

采用原子分光光度法测定牛蒡、银杏、银杏叶和大蒜中Se、Cd、Pb含量,以期为该法用于植物微量元素测定提供参考。