虾塘中新生残饵的N、P营养物质溶出速率及其变化规律研究

通过实验模拟的测定结果,估算了新生残饵对虾塘养殖环境的可能影响程度.结果表明,两种新生残饵的N、P营养物质溶出速率及其TN与TP、IP与TP比值,随其生成时间的延长均有较大幅度变化,且变化趋势相近.贻贝新生残饵因其分解速率较快,故对养殖水体短期影响较大,但其总体影响却并不大于配合饵料.新生残饵是对虾养殖水环境及其临近浅海环境的主要污染源.     

轮叶党参根皮中微量元素溶出率的研究

为开发利用轮叶党参根皮,用５种不同溶液提取,用荧光法、原子吸收法测定Ｚｎ、Ｃｕ、Ｆｅ、Ｍｎ、Ｓｅ等微量元素含量,与原样品中的含量比较,求得各元素在各溶液中的溶出率。结果,Ｆｅ、Ｍｎ、Ｓｅ在酸溶液中,Ｚｎ、Ｃｕ在碱溶液中的溶出率最高,且比传统的水煎、醇提的还要高,值得应用。     

多孔淀粉负载青蒿素微球的溶出、生物利用度和组织分布研究

探讨多孔淀粉负载青蒿素微球（ART-PS）在体外溶出实验中;相比于青蒿素原药的溶出效果以及在大鼠体内的生物利用度和组织分布规律。在体外溶出实验中;分别在水、人工胃液和人工肠液三种溶出介质中;与青蒿素原药的溶出效果进行比较分析。在体内生物利用度实验中;通过对18只大鼠分别灌胃青蒿素原药与多孔淀粉负载青蒿素微球后;检测不同时间点的血药浓度;考察药物在大鼠体内的吸收和代谢差异。在组织分布规律的研究中;对98只大鼠分别灌胃多孔淀粉负载青蒿素微球和青蒿素原药;在不同时间点检测大鼠心、肝、脾、肺、肾、脑;共6个组织器官中的药物浓度。多孔淀粉负载青蒿素微球的体外溶出率在水、人工胃液、人工肠液中分别是青蒿素原药的4.04、3.59和3.82倍。多孔淀粉负载青蒿素微球在大鼠体内的血药浓度明显高于青蒿素原药;生物利用度提高为青蒿素原药的2.90倍。在组织分布的结果中;多孔淀粉负载青蒿素微球和青蒿素原药都主要分布在心脏和肝脏中;其中多孔淀粉负载青蒿素微球在不同时间各个组织中的相应含量都比原药高。多孔淀粉负载青蒿素微球相比于青蒿素原药;在体外的溶出效果更好;在体内的吸收释放效果更佳;在各组织器官中的药物含量明显高于原药;为解决青蒿素因难溶于水而在实际应用中受限提供了重要的理论依据。     

富营养化水体中N、P浓度对浮游植物生长繁殖速率和生物量的影响

在浮游植物生长繁殖的高峰期（7—10月份）对3个富营养化水体的总氮、总磷和浮游植物生物量进行调查,统计分析了生物量与氮和磷浓度的关系。利用3种水样和梯度稀释的东湖水样培养玫瑰拟衣藻（Chloromonas rosae）,研究了氮、磷浓度对生长繁殖速率的影响。结果表明磷是生长繁殖速率的限制因子,求出了生长繁殖速率与磷浓度的对数回归方程y=0．08061nx＋0．4658,当磷浓度小于0．05mg／L时,生长繁殖速率随着磷浓度的升高而直线上升,当磷浓度进一步升高,生长繁殖速率仍然随之增加,但增加的幅度越来越小,当磷浓度达到0．2mg／L时,生长繁殖速率基本不再随着磷浓度的增加而升高。计算出生长速率为零时磷的浓度是0．003mg／L,接近贫营养化湖泊磷浓度的下限,计算结果与坂本的调查统计结果相吻合,说明回归方程具有代表性。在凋查的3个富营养化水体中,浮游植物中的氮占全部氮元素的53％,磷占全部磷元素的85％,是氮、磷存在的主要形式,所以,评价水体的营养程度,必须同时考虑水中溶解的氮、磷和生物体内的氮、磷。统计分析表明,3个富营养化水体中浮游植物的生物量由氮（溶解氮＋胞内氮）和磷（溶解磷＋胞内磷）的浓度共同决定,生物量与氮浓度的直线回归方程y=10．687x-7．8304,生物量与磷浓度的直线回归方程y=122．11x-12．069。实验结果为根据氮、磷浓度以Redfield值判断浮游植物限制性营养元素的相对性和绝对性提供了例证。对3个富营养化水体的比较表明,防止水体富营养的唯一办法是维持水体氮、磷等主要营养元素收支平衡,治理富营养化的根本办法是从水体中移走过量的氮、磷等主要营养元素。     

兔前交叉韧带损伤后膝关节本体感觉、残端血运及膝关节腔尿激酶型纤溶酶原激活物变化的实验研究

摘要 目的：研究兔前交叉韧带（ACL）损伤后膝关节本体感觉、残端血运及膝关节腔尿激酶型纤溶酶原激活物（u-PA）的变化情况。方法：选取80只新西兰兔进行研究,将其以随机数字表法分作模型组及空白对照组各40只。模型组建立单侧ACL损伤模型,空白对照组仅切开关节。比较两组术前及术后2周、4周、8周时膝关节本体感觉、残端血运及膝关节腔u-PA水平的差异。结果：模型组新西兰兔术后2周、4周、8周时的体感诱发电位（SEP）、肌电图（EMG）潜伏期均高于空白对照组,而SEP、EMG波幅均低于空白对照组（P＜0.05）。模型组新西兰兔术后2周、4周、8周时的残端组织微血管密度分别为（2.04±0.24）n/mm²、（2.75±0.61）n/mm²、（1.60±0.33）n/mm²,均高于空白对照组的（1.34±0.24）n/mm²、（1.34±0.25）n/mm²、（1.35±0.26）n/mm²,差异均有统计学意义（P＜0.05）。模型组新西兰兔术后2周、4周、8周时的膝关节液u-PA水平分别为（173.97±14.29）pg/mL、（188.37±15.82）pg/mL、（171.38±14.76）pg/mL,均高于空白对照组的（158.02±10.18）pg/mL、（157.68±10.20）pg/mL、（157.37±10.07）pg/mL,差异均有统计学意义（P＜0.05）。结论：ACL损伤后会在不同程度上影响膝关节本体感觉、残端血运及膝关节腔u-PA含量,值得临床进一步研究。     

4种针叶幼树光合速率,蒸腾速率与土壤含水量的关系及其抗旱性研究

对半干旱区４种针叶幼树的光合速率、蒸腾速率与土壤含水量关系的分析表明,二者均有随土壤含水量下降而减小的趋势,其关系可用回归方程ｙ＝Ａ＋Ｂｅ（－ｋｘ）表示．依此式计算出的净光合速率（Ｙ）等于零时的土壤含水量（Ｘ）值,各树种间有明显的差别,该值小的树种具有较强的抗旱性．其抗旱性顺序为侧柏＞樟子松＞油松＞白扦．     

Evaluation of Gracilaria caudata J. Agardh for bioremediation of nutrients from shrimp farming wastewater

The accelerated development of shrimp farming in Brazil in recent decades has caused negative impacts to the environment. The most evident effects resulting from this activity is the increase in organic material, the reduction in oxygen and the excessive rise in water nutrients. Thus, there is a need for finding alternative solutions that can mitigate the negative impacts caused by this activity. A potentially viable solution is the use of macroalgae to remove nutrients from the cultivation systems. This study examined in situ (shrimp pond), the growth and storage of nitrogen and phosphorous from the macroalga Gracilaria caudata. A short-term measurement experiment was also conducted to evaluate the bioremediation potential this species. These results showed positive values for biomass and growth during the study period, except at day 45 for the tubular nets and day 75 for the cages, when they reached lower values than those of the initial weight. The results obtained indicate that G. caudata may reach annual production of 59.16 ton ha⁻¹ of wet weight, which corresponds to 11.83 ton dry weight. Nitrogen and phosphorous content in the algal tissues increased with time. The mean for the period was 2.61 ± 0.26% and 0.20 ± 0.03% for the nitrogen and phosphorous, respectively. An estimate of the data showed that 1 ha of cultivated algae has the potential to remove 0.309 ton ha⁻¹ year⁻¹ of nitrogen and 0.024 ton ha⁻¹ year⁻¹ of phosphorous. The study of the biofiltration capacity of G. caudata showed a significant reduction in nutrients. The removal of NH₄–N was around 59.5%, NO₃–N 49.6% and PO₄–P 12.3% in 4 h. These results suggest that although G. caudata showed relatively modest growth rates, they can be cultivated together with shrimp and can contribute to the removal of nitrogen and phosphorous from the pond. Moreover, the capacity to efficiently remove nutrients demonstrated in laboratory experiments encourages the use of this alga as a bioremediation agent.     

Application of <Emphasis Type="Italic">Gracilaria lichenoides</Emphasis> (Rhodophyta) for alleviating excess nutrients in aquaculture

A study was conducted in Xiangshan Bay, Ningbo, China, using red alga Gracilaria lichenoides to alleviate nutrient pollution in shrimp (Litopenaeus vannamei) and fish (Epinephelus awoara) culture ponds. Our results showed that G. lichenoides was efficient at absorbing inorganic nitrogen (IN) and inorganic phosphate (IP), and maintained a more stable dissolved oxygen (DO) level. A total of 506.5 kg (1,013 kg ha⁻¹) of shrimp and 210.5 kg (421 kg ha⁻¹) of fish were harvested from the shrimp/algae (SA) and fish/algae (FA) ponds, respectively. Only 53.5 kg shrimp were harvested from the shrimp pond without Gracilaria (S) due to anoxic asphyxia, and 163 kg fish were harvested from the fish culture pond without Gracilaria (F). Compared with using microalgae, bioremediation by macroalgae has no risk of harmful algal blooms (HABs), and it is easy to control seaweed biomass. During the experiment, there was a better environmental condition (lower chemical oxygen demand, IN, IP and chlorophyll a concentrations) in the ponds with Gracilaria. Furthermore, Gracilaria spp. can be used as food for abalone or other aquacultured animals and thus enhance economic return.     

Monocomponent endoglucanase treatment increases the reactivity of softwood sulphite dissolving pulp

Softwood dissolving pulp was treated with a commercial monocomponent fungal endocellulase. The reactivity of the pulp for the production of rayon and cellulose derivatives as determined with the Fock method increased drastically with relatively low amounts of enzyme, and the yield loss and decrease of viscosity were moderate. The mechanism behind the increased reactivity is discussed.     

Preserved ascomatal and other fungal structures on the remains of a ninth century Longobard abbess exhumed from a Monastery in Pavia,Italy

Auxarthron californiense, Mixotrichum aeruginosum, Oncocladium flavum and Chaetomium elatum were recognized on the basis of ascomatal structures on the remains of a Longobard abbess who died in the IX century A.D. These fungi, which had remained isolated in a crypt of the S. Felice Monastery of Pavia for almost 1000 years, are phenotypically identical to the type specimens. The occurrence of these fungi and their ecological role are discussed. This revised version was published online in August 2006 with corrections to the Cover Date.     

一些细菌和真菌的解磷能力及其机理初探

4株细菌和8株真菌培养6天后,发现培养液中有机酸含量大幅度增加,PH大幅度地下降,磷的含量大幅度增加,真菌比细菌表现出更强的溶解磷矿粉的能力,不同的微生物分泌有机酸的数量和种类差别很大,菌分泌的有机酸种类比细菌要多。但是,培养液中有机酸总量与解磷量之间并不存在显的相关性。     

α-肾上能受体兴奋剂及阻断剂对米虾棕色载色细胞内色素聚散的效应

萘唑啉或肾上腺素能使米虾离体棕色胞内色素集中,此作用被酚妥拉明短时所阻断。异丙肾上腺素对棕色胞无影响。作者认为棕色胞上只具有α受体,可以作为筛选α受体兴奋剂及阻断剂的模型。     

长毛对虾精子发生的研究：Ⅰ.精子的形态结构

利用电子显微镜技术结合细胞化学染色方法,研究长毛对虾精子形态结构,结果显示:长毛对虾精子由圆球状球体部和钉子状棘突部组成;精子全长约7μm;棘突及与之相联的球体表面平滑无突起,而与棘突相对的球体底面有指状突起。透射和冷冻蚀刻电镜显示:长毛对虾精子棘突包括顶体锥和顶体帽两部分;顶体锥向外突出形成精子的棘突,顶体帽覆盖在球体部的胞质及核区上方。成熟精子胞质极度退化,仅靠顶体帽边缘可见1—2个线粒体。球体的中央区域为近球形,呈Feul-gen阳性反应,为精子的核区。其结构松散,电子密度低,属非浓缩型,内布许多絮状物质,外由许多长短不一的膜性结构不规则排列成不连续的核膜结构。研究结果认为:长毛对虾精子属不动无鞭毛精子类型,其棘突部并非鞭毛结构而是顶体的位置。     

酸雨对温州三土羊湿地水体氮营养盐数量的影响

为了解酸雨对温州三垟湿地水体氮营养盐数量的影响,本文测定了三垟湿地水体中不同形态氮的含量,其中氨氮2.90～10.75 mg·L^-1,平均5.38 mg·L^-1、硝态氮0.16～0.44 mg·L^-1,平均0.31 mg ·L^-1;总氮34.04～63.20 mg·L^-1,平均55.75 mg·L^-1和水体的pH值,6.1～6.5,平均6.4;并测算了近两年通过降水输入到三垟湿地和三垟湿地水体中不同形态氮的数量及其占湿地现有水体中各形态氮的比例,其中输入到三垟湿地氨氮、硝态氮和总氮的量分别为2.8～2.86× 10 kg、2.87×10⁴～4.96×10⁴kg和5.35×10⁴～7.82×10⁴ kg,分别占湿地水体现有量的56%～6%、11.21～19.38倍和12%～17%;直接输送到三垟湿地水体各形态氮的数量0.72×10⁴～0.8×10⁴ kg、0.83×10⁴～1.44×10⁴ kg和1.55×10⁴～2.27×10⁴,分别占现有量的16%～19%,3.24～5.63倍和3%～5%.结果表明,酸雨是三垟湿地水体氮污染的主要来源之一,对三垟湿地水体富营养化产生重要影响.