全球商品种子市场价值有望在2018年达到533.2亿美元

<正>透明度市场研究(Transparency Market Research)发布了一项传统种子和生物技术种子市场2012年到2018年的全球产业分析。2011年全球商品种子市场市值345亿美元,2018年有望达到533.2亿美元。生物技术种子市场2011年市值为156亿美元,2018年有望达到301.2亿美元。分析报告强调生物技术种子市场在过去十年间一直在增长,未来六年更有望达到两位数增长。而且,未来还会有新的生物技术种     

珠江下游广东鲂体长-体重关系和肥满度的年间变化北大核心CSCD

本研究通过对2010至2018年珠江下游肇庆江段广东鲂(Megalobrama terminalis)的生物资料调查,探究了其体长-体重关系以及肥满度及年龄结构年间变化趋势。结果表明,2010至2018年珠江下游肇庆段广东鲂种群的体长及5+龄以上个体占比率总体呈现下降趋势。2010至2018年珠江下游广东鲂种群体长-体重幂函数相关的条件因子a为0.011~0.004,异速生长因子b为2.816~3.261。广东鲂种群在2010、2011和2014年呈现负异速生长,而在2013及2015至2018年份表现出正异速生长。2010至2018年珠江下游广东鲂种群肥满度总体呈现出上升趋势。此外,2010至2018年珠江下游肇庆段日平均水温20℃以上天数占比率呈现逐渐上升趋势,而洪峰数量减少且相对集中。本研究发现广东鲂异速生长因子与日平均水温和径流量呈现一定线性正相关关系,揭示栖息地环境与广东鲂生长潜在的关联性。持续的高捕捞压力加快了广东鲂种群生长速度,并导致了该种群负异速生长。珠江禁渔期制度实施及其栖息地水温变化,可能是珠江下游广东鲂种群肥满度逐渐升高的原因。     

酶制剂发展应用及相关问题

<正>不论是酶,还是工业应用的酶制剂,从来不是个大行业,将来也不大可能成为一个很大的行业。不同来源的统计显示,2018年全球工业酶制剂的市场约为55亿～60亿美元。Markets And Markets公司2014年的报告"Industrial enzymes—global trends and forecasts to 2018"中预估2018全球工业酶制剂市场为55亿美元;2018年BCC Research公司的最新报告"Global market for enzymes     

长江流域生态系统服务价值时空演变与预测

长江流域是我国的经济重心和生态保育区,揭示其生态系统服务价值(ESV)的历史演变和发展趋势对支撑长江流域的生态经济系统持续发展具有重要意义。采用长江流域1992—2018年逐年土地利用数据,构建了基于修正系数的ESV评估模型和FLUS-Markov土地利用预测模型,解析了全流域ESV的历史演变特征和未来2030年变化趋势。结果表明：(1)2018年长江流域的ESV总量11.68×10¹²元,1992—2018年ESV呈上升趋势,年均提高297.00×10⁸元;(2)供给服务价值是流域ESV的最大贡献源,占总量的48.3%—51.8%,文化服务价值是增长最快的贡献源,1992—2018年增长了52.5%;(3)上游地区是长江流域ESV最集中的区域,上游ESV占全流域的45.15—46.8%,从1992年到2018年,长江流域ESV重心有向下游流动的趋势;(4)2030年长江流域的建设用地将进一步扩展,同时耕地、草地面积有下降的风险,2030年长江流域的ESV新增量达到0.36×10¹²元,主要来自娱乐和气候调节服务价值的提...     

三江源地区环境足迹及居民福祉的动态变化特征评价

环境足迹表征人类发展过程对环境的影响程度。环境足迹和居民福祉水平是衡量区域可持续发展能力的重要指标。计算了2000—2018年三江源地区的环境足迹与环境边界，构建了三江源地区居民福祉评价框架，评估了2000—2018年三江源地区环境足迹及居民福祉的耦合协调关系及动态变化特征，得到了2000—2018年三江源地区环境足迹与居民福祉间的定量关系，可为有关部门制定合理的区域发展策略提供科学支撑。结果表明：(1) 2000—2018年三江源地区人均环境足迹呈一直超过环境边界限额的状态。(2)三江源地区居民福祉按重要性排序表现为社会文化福祉高于安全健康福祉和基本需求福祉。2000—2018年，三江源地区居民福祉总体呈波动式上升趋势，其中安全与健康福祉的波动最大且对居民福祉的贡献度最高。(3)三江源地区环境足迹与居民福祉的耦合度与耦合协调度呈现波动上升趋势，二者关联水平逐渐提高，逐步趋于协调发展。     

博耶和科恩重组质粒转化实验所证明的生物学内涵

高考题是对高中各学科重要知识点的集中体现,2017年和2018年的全国卷Ⅰ生物学高考题中,都对基因工程的相关知识进行了考核,充分说明基因工程相关知识在高中生物学中的重要性。从2018年高考题第38题的答案出发,对博耶和科恩的重组质粒转化实验所证明的生物学内涵进行分析。     

粤港澳大湾区城镇化对海岸线与海岸带的影响

海岸带以丰富的自然资源与优越的地理位置成为城镇化的关键地带。基于Google Earth平台2001、2010、2018年高分影像识别分析了粤港澳大湾区快速城镇化过程中海岸线长度的变化,并分析了大湾区海岸带土地利用/土地覆被(land use/land cover, LULC)变化,以及定量解析了大湾区滨海城市城镇化与海岸带城镇用地的关联关系。结果表明:(1)2001—2018年,粤港澳大湾区海岸线总长度净增加32.24 km,但自然岸线人工化问题突出,自然岸线共减少187.67 km,人工岸线共增加219.91 km;(2)海岸带(海岸线向陆侧5 km缓冲区) LULC组成以耕地为主,但城镇用地对耕地的侵占问题突出,2001—2018年,耕地面积减少347.58 km~2,城镇用地面积增加588.33 km~2;(3)2001—2018年,滨海城市土地城镇化与海岸带城镇用地增长呈显著相关,并且滨海城市土地城镇化对海岸带城镇用地增加的影响在加强(2001—2010年和2010—2018年贡献率分别为43.7%和68.51%)。研究结果可对粤港澳大湾区海岸带保护、修复以及土地利用规划管理...     

晋北大型露天矿区景观生态风险时空异质性

矿产资源开采对生态环境产生了剧烈扰动,加剧了矿区生态环境的风险性,严重威胁区域的可持续发展。从景观生态学角度将景观格局与生态风险相结合对矿区生态环境进行评估,从而揭示矿区景观生态风险的时空异质性,促进土地资源的可持续利用。以1990-2018年7期Landsat TM影像解译后的土地利用现状数据为数据源,构建景观生态风险指数,结合空间统计学及地统计学理论,探究1990-2018年平朔矿区景观生态风险的时空异质性。结果表明:1990-2018年平朔矿区景观生态风险的空间分布呈集聚分布模式,Moran’s I指数处于0.53~0.68,Z得分远高于检验阈值1.96,风险的空间集聚效应明显。1990-2018年平朔矿区的景观生态风险等级以中低、中、中高水平为主,占全区总面积的70%~90%,低风险区域主要分布于井坪镇以及白堂乡与向阳堡乡的大片林地,耕地是中等风险的主要分布区域,高风险区域逐渐向矿界内的矿业核心区收缩。1990-2018年平朔矿区景观生态风险空间异质性中的随机变异均小于空间自相关变异,由空间自相关部分引起的空间异质性占据主导地位。研究表明,在0.50 km×0.50 km的研究尺度下,1990—2018年平朔矿区景观生态风险具有很强的时空异质性,时间上呈现先增加后降低的趋势,空间相关性显著,空间分异特征明显。     

我院2015-2018年度抗菌药物的使用强度与鲍曼不动杆菌的耐药性的关系研究

摘要 目的：分析我院2015-2018年度抗菌药物的使用强度与鲍曼不动杆菌的耐药性的关系。方法：统计2015年1月～2018年12月北京中医医院顺义医院抗菌药物的应用情况以及鲍曼不动杆菌的耐药性。鲍曼不动杆菌的耐药性资料来源于检验科临床送检的伤口分泌物、痰液、血液、尿液等病原学标本。结果：2015年～2018年,共分离到菌株13246株,其中分离到鲍曼不动杆菌株1927株,分离率为14.55 %。其中 2015 年的分离率为3.11 %,2016年的分离率为4.51 %,2017 年的分离率为5.15 %,2018 年的分离率为2.11 %;鲍曼不动杆菌标本分离率最高的为痰液,占78.83 %,其次为伤口分泌物,占12.51 %,尿液标本占5.81 %,血液标本占2.85 %;鲍曼不动杆菌在我院所有致病菌中的排序均为第一位或者第二位;2015年～2018年抗菌药物的使用强度逐年升高,2018年有所降低;2015年～2018年鲍曼不动杆菌对哌拉西林钠他唑巴坦钠、美洛培南以及亚胺培南的耐药率均逐年升高,2018年有所降低;哌拉西林钠他唑巴坦钠、美洛培南以及亚胺培南的耐药性与抗菌药物使用强度之间具有明显的相关性（P<0.05）。结论：哌拉西林钠他唑巴坦钠、美洛培南以及亚胺培南的使用,是造成鲍曼不动杆菌耐药的重要原因之一,临床应加以重视。     

2018年中国植物科学若干领域重要研究进展

2018年中国植物科学继续呈现快速发展的态势, 我国科学家在国际植物科学主流学术刊物发表论文数量大幅增加, 取得了多项具有重要影响的成果。调控植物生长-代谢平衡实现可持续农业发展入选2018年度中国科学十大进展; 中国被子植物区系进化历史研究入选2018年度中国生命科学十大进展。以水稻为代表的农作物和果蔬等经济作物研究在国际上已呈现出明显的优势, 若干领域已从“追赶”状态跨越到“领跑”地位。该文对2018年中国科学家在植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪和报道当前中国植物科学领域的发展前沿和热点, 展示中国科学家所取得的杰出成就。     

Carbohydrate metabolism in Musa paradisiaca

Considerable variations exist in the content of glucose, fructose, sucrose, starch and protein and in the activities of enzymes involved in carbohydrate metabolism between different parts of the banana plant (Musa paradisiaca). Sucrose synthetase is present in the highest concentration in rootstock and fruit pulp, and sucrose phosphate synthetase in the pseudostem. The highest ratio of the activity of sucrose phosphate synthetase to sucrose synthetase is found in leaves. Acid invertase is present in leaves, leaf-sheath and fruit pulp and is not demonstrable in rootstock and pseudostem. Neutral invertase activity is high in pseudostem and leaf-sheath. Starch phosphorylase is largely concentrated in fruit pulp and rootstock. The maximum activity of ATP:d-phosphoglucose (ADPG) pyrophosphorylase is found in rootstock. β-Amylase is not demonstrable in rootstock and is largely concentrated in leaf-sheath. Hexokinase is most active in rootstock and the lowest in leaves. Acid phosphatase and alkaline phosphatase activity is highest in fruit pulp and pseudostem. Glucosephosphate isomerase is most active in the rootstock and lowest in the leaves.     

Continuous social defeat induces an increase of endogenous opioids in discrete brain areas of the mongolian gerbil

Dyads of a victor and a loser of mongolian gerbils (Meriones unguiculatus) coexisted for seven days; isolated animals served as a further experimental group. beta-Endorphin, Met-enkephalin and dynorphin were measured in several brain areas and in the anterior and neurointermediate pituitary. beta-Endorphin and Met-enkephalin were increased in the amygdala of defeated as compared to victorious animals. Met-enkephalin in the hypothalamus and in the striatum were lower in isolated than in coexisting gerbils. Coexistence decreased beta-endorphin in the amygdala and in the hypothalamus as compared to isolation. The results provide biochemical evidence for the role of central endogenous opioid-peptide systems in the physiology of victory and defeat. Dynorphin showed no variation with social conflict and social status.     

羚牛(Budorcas taxicolor)部分脏器特点的观察

本文对2只羚牛的雌性生殖器官及肝、肾、脾等脏器进行了形态描述,并与黄牛及羊的相应器官进行了比较,为探讨羚牛的分类地位提供了解剖学资料。     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

花生荚果发育过程中子叶细胞的超微结构和脂酶活性的研究

在花生(Arachis hypogaea)荚果发育过程中,子叶细胞的超微结构和脂酶活性皆发生了显著变化。子叶生长初期,缅胞中质体较多,并不断形成淀粉粒;脂酶活性低,脂体和蛋白体很少。子叶发育中期,子叶细胞质中出现大量体积较大的脂体,液泡中的蛋白体不断形成和增大,而且细胞质、内质网、蛋白体外膜、细胞质膜和细胞间隙上皆显示较强的脂酶活性。子叶发育后期,脂体数量不再增加,但体积略有增大,间质透明度也有提高;蛋白体增大较小,但数量却进一步增多;细胞质中仍显示较强的脂酶活性。至末期时,蛋白体形态变得不规则,甚至出现部分解体,其基质充挤脂体间隙;细咆中的脂酶活性减弱。研究表明,花生脂体起源于细胞质,蛋白体起源于液泡,子叶油分和蛋白质的积累足体内脂体和蛋白体不断发育的结果,细胞中脂酶活性的变化可能与脂体发育有关。     

Influence of litter and weather on seedling recruitment in a mixed oak-pine woodland

The effects of regular litter removal and annual variation in temperature and precipitation on seedling recruitment of species differing in their seed size and mode of dispersal were studied in a 16-year (1984-1999) experiment in a mixed oak-pine wood in southern Poland. Litter was the most important factor in determining spatial variability in seedling recruitment, whereas differences in climatic conditions among years, especially temperature fluctuations in late winter and early spring, determined the temporal variability in seedling recruitment. Compared with control plots, significantly more new individuals of bryophytes and seedlings as well as a number of new species of vascular plants were noted in the litter-removal plots over the 16-year study. Litter strongly impeded seedling emergence of small-seeded species. The negative effect of litter on seedling recruitment of large-seeded species and the recruitment of new shoots in species growing clonally was much weaker. There was a significant positive correlation between the numbers of seedlings in the litter-removal and control plots and temperatures in January to March. In the litter-removal plots this mainly affected small-seeded species. Seedling recruitment was less consistently related to variation in precipitation. Positive relationships were found only between the number of seedlings of large-seeded species in the litter-removal plots and precipitation in July of the current year and in September of the previous year, and between the number of seedlings in the control plots and precipitation in September and November of the previous year.     

Short-term accumulation of organic matter and nutrient contents in two dry sand ecosystems

Inland dunes in northwestern Europe support a number of dry vegetation types. These ecosystems are poor in nutrients and it has been suggested that accumulation of nutrients triggers succession in such systems.We studied the accumulation of organic matter and N and P over a 30 months period in two adjacent ecosystems, the Spergulo-Corynephoretum and the Genisto-Callunetum. Amounts of plant matter and soil organic matter significantly accumulated during the sampling period in the Genisto-Callunetum but not in the Spergulo-Corynephoretum. While nutrient concentrations of live and dead phytomass in the Spergulo-Corynephoretum were significantly higher than in the Genisto-Callunetum, total nutrient contents in the systems showed the opposite pattern. N and P concentrations in litter were relatively high compared with the other fractions of plant matter and the amount of N significantly increased in both ecosystems during the sampling period. Soil moisture contents showed a seasonal pattern. It was highest in the top soil layer and higher in the Genisto-Callunetum than in the Spergulo-Corynephoretum.The estimated annual increase of total N in these two ecosystems was consistent with rates of atmospheric N deposition (wet fall + dry fall) measured in comparable Dutch sites.     

Distribution of galanin-like immunoreactivity in the gastro-intestinal tract of several mammalian species

Summary The distribution of galanin-immunoreactive (GAL-IR) neurons was mapped in detail in the gastro-intestinal tract of the rat, mouse, guinea-pig and pig by use of the indirect immunofluorescence technique. GAL-IR cell bodies were found in both the submucous and the myenteric plexus, with considerably higher numbers in the former ganglia. The largest number of GAL-IR perikarya was seen in the duodenal submucous plexus of the pig. With some (single) exceptions, GAL-IR cell somata were not observed in the myenteric plexus of the pig and guinea-pig, and in the submucous plexus of the esophagus and the stomach of the guinea-pig.GAL-IR fibers ocurred in most parts of the gastro-intestinal tract. In the lamina propria a few non-varicose, weakly fluorescent fibers were noted in the mouse and rat, whereas in the pig and guinea-pig were large numbers of GAL-IR fibers with a varicose appearance was observed. These fibers were in all species most numerous in the distal portion of the intestinal tract. In the submucosa GAL-IR fibers were detected in all four species, and in the pig and guinea-pig some fibers surrounded blood vessels. A large number of GAL-IR fibers was generally seen in the circular smooth muscle layer, except in the guinea-pig, which only seemed to contain a few fibers. In the longitudinal muscle layer only single fibers could be detected. However, the gastric fundus region of the pig contained a moderate number of fibers in the longitudinally and obliquely oriented layers.In general, in the rat, mouse and pig, the submucous and myenteric plexus contained moderate or large numbers of GAL-IR fibers. In the guinea-pig, no or only single fibers were observed in the plexus of the upper gastro-intestinal tract and the rectum, while moderate numbers were seen in the ileum and colon.Thin adjacent sections stained for vasoactive intestinal polypeptide (VIP) and GAL revealed the coexistence of these two peptides in cell bodies of the myenteric plexus in the pig duodenum and guinea-pig colon. In these two species the GALand VIP-nerve fiber networks also exhibited marked similarities. However, in the rat and mouse VIPand GAL-distribution patterns were in general different.The present findings indicate the presence of yet another neuropeptide or peptide family in the gastro-intestinal tract of several rodents and the pig.     

Localization and correlation between NADPH-diaphorase and nitric oxide synthase isoforms in the porcine uterus during the estrous cycle

Nitric oxide (NO), a highly reactive free radical is involved in vasodilation, neurotransmission, hormone secretion, and reproduction. Since all known nitric oxide synthase (NOS) isoforms possess NADPH-diaphorase (NADPH-d) activity, NADPH-d histochemistry was used as a commonly accepted procedure for NOS identification. The aim of our study was to determine the cellular localization of NADPH-d, eNOS, and iNOS in the porcine uterus and the correlation between NADPH-d and NOS activity in the early, middle, late luteal, and follicular phase of the estrous cycle. Light-microscopic observations of the sections revealed the differential expression of the NADPH-d in the analyzed stages of the estrous cycle. The most intense staining was observed in the luminal epithelium in the late luteal phase and in some groups of the endometrial glands in all studied stages. Positive reaction was also found in the endothelial cells of blood vessels and in the myometrium itself. Immunostaining for eNOS was observed in the luminal and glandular epithelium in all studied stages, but no clear fluctuations were observed. The endothelium of both endometrial and myometrial blood vessels displayed pronounced eNOS immunostaining. Strong iNOS staining was observed in the luminal epithelium in the late luteal and follicular phase and in selected groups of endometrial glands. Thus, only NADPH-d and iNOS undergo cyclic changes in the studied stages of the estrous cycle. The differential expression of NADPH-d/NOS in the porcine uterine horn during the estrous cycle suggests a role for NO in modulating uterine function.     

Distribution,ontogeny and ultrastructure of somatostatin immunoreactive cells in the pancreas and gut

Summary Somatostatin cells are numerous in the pancreas and digestive tract of mammals as well as birds. In the pancreas of chicken, cat and dog they occur in both the exocrine parenchyma and in the islets. In the rat and rabbit, somatostatin cells have a peripheral location in the islets, whereas in the cat, dog and man the cells are usually more randomly distributed. In the stomach of rabbits and pigs, somatostatin cells are more numerous in the oxyntic gland area than in the pyloric gland area, whereas the reverse is true for the cat, dog and man. In the cat, pig and man, somatostatin cells are fairly numerous in the duodenum, whereas in the rat, rabbit and dog they are few in this location. In the remainder of the intestines somatostatin cells are few but regularly observed. Somatostatin cells are numerous in the human fetal pancreas and gut. In the fetal rat, somatostatin cells first appear in the pancreas and duodenum (at about the 16–17th day of gestation) and subsequently in the remainder of the intestine. Somatostatin cells do not appear in the gastric mucosa until after birth. Three weeks after birth, somatostatin cells show the adult frequency of occurrence and pattern of distribution. In the chicken, somatostatin cells are numerous in the proventriculus, absent from the gizzard, abundant in the gizzard-duodenal junction (antrum), infrequent in the duodenum and virtually absent from the remainder of the intestines. No immunoreactive cells can be observed in the thyroid of any species nor in the ultimobranchial gland of the chicken. In the chick embryo, somatostatin cells are first detected in the pancreas and proventriculus (at about the 12th day of incubation). They appear in the remainder of the gut much later, in the duodenum at the 16th day, in the antrum at about the 19th day and still later in the lower small intestine. The ultrastructure of the somatostatin cells was studied in the chicken, rat, cat and man; the cells were identified by the consecutive semithin/ultrathin section technique. The somatostatin cells display the properties of the D cell. There was no difference in granule ultrastructure between somatostatin cells in the gut and the pancreas. The granules, which are the storage site of the peptide, are round, supplied with a tightly fitting membrane and have a moderately electron-dense, fine-granulated core. The mean diameter of the somatostatin granules is smallest in rat (155–170 nm) and largest in the chicken (270–290 nm).