镧对马尾松苗的根系生长和IAA含量的影响

在０．１～１．０ｍｇ／Ｌ硝酸镧的Ｈｏａｇｌａｎｄ培养液中,马尾松（ＰｉｎｕｓｍａｓｏｎｉａｎａＬａｍｂ．）截根苗的侧根数目明显增加,为对照的１．７５～３．７５倍;根的鲜重、干重显著提高,增幅达３３．７％～４６．４％;根系还原力也提高１３．５％～２８．５％。根长仅在０．０５～０．５ｍｇ／Ｌ的低浓度下比对照有所增加,在浓度高于１．０ｍｇ／Ｌ时,根长只有对照的５３．３％。侧根内的游离态ＩＡＡ含量随溶液中镧的浓度增加而相应增加,ＩＡＡ氧化酶的活性则相应降低。硝酸镧处理对该苗地上部的促进效应不如根部显著。     

ELISA技术筛选200种中草药抗HBsAg的实验研究

使用ＥＬＩＳＡ技术对２００种中草药水提取物进行抗ＨＢｓＡｇ的实验研究,共筛出有效药物７种（占总数的３．５％）。若按５种不同剂量（０．３、０．６、１．２、２．５、５．０ｍｇ／１００μｌ）的药物、２种不同浓度的ＨＢｓＡｇ（１０．９２、１４．２６Ｐ／Ｎ值）与３种不同接触时间（立即、１ｈ、２ｈ）的１０项Ｐ／Ｎ值均数来综合评价药效指数时,７种有效药物的次序为青蒿（１．６７Ｐ／Ｎ值）、大蒜（２．１９Ｐ／Ｎ值）、红孩儿（２．３１Ｐ／Ｎ值）、仙鹤草（２．３１）、魔芋（２．３２Ｐ／Ｎ值）、冬瓜皮（２．６３Ｐ／Ｎ值）和猕猴桃（２．８９Ｐ／Ｎ值）。     

重金属对蚕豆的细胞遗传学毒理作用和对蚕豆根尖微核技术的探讨

Ｐｂ２＋ 、Ｃｄ２＋ 和Ｈｇ２＋ 显著地缩短蚕豆（Ｖｉｃｉａ ｆａｂａ Ｌ．）根尖细胞分裂的持续时间,延长细胞间期的时间间隔,在总体上延长了细胞分裂周期;除Ｈｇ２＋ 随浓度升高一直表现为对有丝分裂抑制外,在Ｐｂ２＋ 、Ｃｄ２＋ 和Ｚｎ２＋ 浓度分别小于１．０、０．０１、１０．０ ｐｐｍ 时,细胞有丝分裂指数随处理浓度升高而上升,当超出上述浓度时则随浓度升高而下降;微核率（ＭＣＮＦ）在Ｐｂ２＋ 、Ｃｄ２＋ 、Ｈｇ２＋ 和Ｚｎ２＋ 的浓度分别小于１．０、５．０、０．５０、１００．０ ｐｐｍ 时,染色体畸变率（ＣＡＦ）在Ｐｂ２＋ 、Ｃｄ２＋ 、Ｈｇ２＋ 和Ｚｎ２＋ 的浓度分别小于５．０、５．０、０．５０、１００．０ ｐｐｍ 时,这两参数随处理浓度的升高而增大;超过上述浓度后,则随处理浓度升高而下降。Ｍｎ２＋ 对各项参数无显著影响。对蚕豆根尖细胞遗传学毒性顺序为Ｈｇ２＋ ＞ Ｃｄ２＋ ＞ Ｐｂ２＋ ＞ Ｚｎ２＋ ＞ Ｍｎ２＋ 。经综合分析,３ 个参数在不同剂量范围下相关性程度有很大的差异。认为蚕豆根尖微核技术检测危险化学品和监测环境污染时取得可靠结果的条件是：受检物质在检测条件下不严重抑制细胞分裂和ＣＡＦ和ＭＣＮＦ呈正相关     

NaCl胁迫对螺旋藻生长及抗氧化酶活性的影响

在０１％～５．０％ＮａＣｌ浓度范围的培养基中培养极大螺旋藻（Ｓｐｉｒｕｌｉｎａｍａｘｉｍａ）,发现ＮａＣｌ浓度高于２．０％时螺旋藻生长受到明显抑制。培养７天后测定超氧化物歧化酶（ＳＯＤ）、抗坏血酸过氧化物酶（ＡＳＡＰＯＤ）、过氧化氢酶（ＣＡＴ）活性和丙二醛（ＭＤＡ）含量。结果表明：在盐胁迫下,ＳＯＤ酶活性升高;抗坏血酸过氧化物酶和过氧化氢酶活性在低盐胁迫下活性升高,高盐胁迫下抗坏血酸过氧化物酶活性迅速降低,过氧化物酶则完全失活;ＭＤＡ含量先随盐胁迫程度增加而降低,后随盐胁迫的进一步增强恢复至对照水平。     

洗涤剂LAS在土壤上吸附行为及机理研究

使用连续反应器研究了２５℃温度ＬＡＳ正土壤上吸附的行为和机理,ＬＡＳ在自然土壤上的吸附等温线可分成线性和指数增长两个阶段,在低ＬＡＳ浓度（＜９０μｇｍｌ＾－１）下,吸附着温线为直线,Ｋｄ＝１．２－２．０在高ＬＡＳ深度（＞９０μｇｍｌ＾－１）时,ＬＡＳ产生协同吸附,吸附量呈指数增加,土壤吸附ＬＡＳ的机理主要是专点位表面相互作用及氢键,吸附容量主要取决于土壤物理性粘粒的含量。     

中缝隐核投射至中脑导水管周围灰质腹侧部的递质分析

实验在戊巴比妥钠麻醉大鼠上进行。双侧中脑导水管周围灰质腹侧部（ｖＰＡＧ）微量注射１μｇ／μｌ肾上腺素（每侧０．１μｌ）,刺激中缝隐核（ＮＲＯ）引起的降压反应明显增强,但该效应可被ｖＰＡＧ预先注射心得安所阻断,而注射酚妥拉明对上述效应无明显影响;ｖＰＡＧ内单独微量注射１μｇ／μｌ心得安（每侧０．１μｌ）,可部分阻断ＮＲＯ降压反应,而注射１μｇ／μｌ酚妥拉明（每侧０．１μｌ）无明显影响;双侧ｖＰＡＧ微量注射１０μｇ／μｌ吗啡或０．１ｍｏｌ／Ｌ５－ＨＴ（每侧０．１μｌ）,基础血压无明显变化,ＮＫＯ的降压反应幅度减小（Ｐ＜０．０５）。提示,ＮＫＯ对ｖＰＡＧ的兴奋作用的可能递质为肾上腺素,通过β受体介导;吗啡或５－ＨＴ则可减弱ＮＲＯ对ｖＰＡＧ的兴奋性投射作用。     

使用ELISA技术检测中草药抗HBeAg的实验研究

使用ＥＬＩＳＡ技术对２５０种中草药水提取物进行抗ＨＢｅＡｇ的实验研究,共筛出有效药物７种（占总数的２．８％）。若按５种不同剂量（０．３、０．６、１．２、２．５、５．０ｍｇ／１００μｌ）的药物、２种不同浓度的ＨＢｅＡｇ（１０．９２、１４．２６Ｐ／Ｎ值）与３种不同接触时间（立即、１ｈ、２ｈ）的１０项Ｐ／Ｎ值均数来综合评价药效指数时,７种有效药物的次序为丹参（１．５５）、皂夹（２．３４）、黄莲（２．８１     

甜瓜的组织培养与快速繁殖

１植物名称甜瓜（Ｃｕｃｕｍｉｓｍｅｌｏ）品种“状元”。２材料类别顶芽、侧芽。３培养条件初代培养基：（１）ＭＳ＋６－ＢＡ０．２ｍｇ·Ｌ－１（单位下同）＋ＩＡＡ０．２。增殖培养基：（２）ＭＳ＋６－ＢＡＩ＋ＩＡＡ０．２。生根培养基：（３）Ｍｉｌｌｅｒ＋ＩＡＡ０．２;（４）Ｍｉｌｌｅｒ（无激素）。以上培养基ｐＨ均为５．８～６．０。琼脂浓度在（１）、（２）中为０．７％,在（３）、（４）中为０．６％;糖浓度在（１）、（２）中为３％,在（３）、（４）中为２％。培养温度均为（２５±３）℃,光照度２０００ｌｘ,光…     

正常足月儿畸变产物耳声发射(DPOAEs)特性分析

研究提出正常足月儿畸变产物耳声发射（ＤＰＯＡＥｓ） 特性分析如下：１ ． ＤＰＯＡＥｓ 反应强度曲线,ＤＰ 图显示两个反应峰（ｆ２ ＝ １ ．６ 和５ ．０ ｋＨｚ） 和一个反应谷（ｆ２ ＝ ３ ．１ ～４ ．０ ｋＨｚ） ;２． ＤＰＯＡＥ 本底噪声及其特性,ｆ２ ＝ １．０ ｋＨｚ 其测试频率点（２ｆ１ －ｆ２） 本底噪声最高（Ｐ＜ ０ ．０５） ,ｆ２ ＝ ３ ．１ ,４．０ 和５ ．０ｋＨｚ ,测试频率点（２ｆ１ －ｆ２） 本底噪声较低（Ｐ＜ ０．０５） ;除ｆ２ ＝ ４．０ ｋＨｚ 外,ＤＰＯＡＥ 本底噪声与其反应强度均未呈现直线相关特性;３ ． ＤＰＯＡＥ ＳＮＲ 特性,ｆ２ ＝ １．０ ｋＨｚ 其ＳＮＲ 最小（Ｐ＝ ０．０００） ,ｆ２ ＝２ ．０ ｋＨｚ 其ＳＮＲ 最大（Ｐ０ ．００３） ;４． ＤＰＯＡＥ ＳＮＲ 和ＴＥＯＡＥ ＳＮＲ 相关特性,除１．０ ｋＨｚ 频段外,其余频段其二者间均有着非常显著的直线相关特性。     

巨大芽孢杆菌D01吸附金(Au3+)的研究

巨大芽孢杆菌（Ｂａｃｉｌｌｕｓ ｍｅｇａｔｅｒｉｕｍ）Ｄ０１菌体吸附ＡＵ＾３＋的最适ｐＨ值为３．０,其生物吸附作用是一种快速的过程,最初５ｍｉｎ 的吸附量可达到最大吸附量的９５％,温度不影响该吸附作用。在ｐＨ３．０和３０℃、起始金离子浓度与菌体浓度之比为３０５ｍｇ／ｇ的条件下,吸附３０ｍｉｎ,吸附率达９９．１％,吸附量为３０２．０ｍｇ／ｇ干菌体。Ｄ０１菌体能将浓度中的Ａｕ＾３＋还原成Ａｕ＾０,在细     

Gross structure and dimensions of the gills in a hill-stream sisorid catfish,Glyptothorax pectinopterus

Gross structure and dimensions of the gills have been examined in a hill-stream sisorid catfish,Glyptothorax pectinopterus, which remains adhered to rocks by means of an adhesive organ developed on the ventral side of the thorax. The fish shows a greater weight-specific gill area and greater length of the gill filaments by comparison with other hill-stream fishes. Adaptation for life in a hill-stream habitat is shown by the presence of additional filaments on the gills and patches of specialised cells on the filament epithelium.     

Autoradiographic analysis of amino acid uptake by the gill ofMytilus

Summary Autoradiography was used to examine the influence of lateral ciliary activity on the pattern of leucine uptake into isolated gill tissue from the mussel,Mytilus californianus. Metachronal activity of the lateral cilia, normally absent in the in vitro gill, was reestablished by application of 10 μM 5-hydroxytryptamine (5-HT). This treatment produced a 5–7 fold stimulation in the rate of leucine uptake into isolated gills. The treatment with 5-HT did not, however, affect the fractional incorporation of leucine into alcohol insoluble vs alcohol soluble material. Autoradiograms of gills treated with 5-HT showed extensive labelling of frontal, lateral, and abfrontal surfaces of gill filaments compared to the control condition in which label was largely confined to the frontal region of the gill. Quantitative analyses of the autoradiograms revealed a 4-fold increase in the number of silver grains over lateral and abfrontal surfaces compared to control gills. Autoradiograms of gills from intact mussels exposed to³H-leucine showed a pattern of silver grain deposition similar to that observed in in vitro gills treated with 5-HT. It is concluded that the capacity for amino acid transport exists in cells from the frontal, lateral, and abfrontal surfaces of gill filaments, butaccess to dissolved substrates by transport sites on lateral and abfrontal surfaces is dependent upon lateral ciliary activity.     

Differences in host selection of actinospores of two myxosporeans, Myxobolus arcticus and Thelohanellus hovorkai

We investigated the host selection mechanism of actinospore stages of 2 myxosporeans, Myxobolus arcticus and Thelohanellus hovorkai, infecting masu salmon (Oncorhynchus masou) and common carp (Cyprinus carpio), respectively. Discharge of the polar filaments and sporoplasm release by M. arcticus actinospores occurred within the first 5 min of exposure to skin mucus of masu salmon. The actinospores also reacted to the mucus of nonsusceptible fish, i.e., sockeye salmon (Oncorhynchus nerka) and goldfish (Carassius auratus), although the reactivity was comparatively lower. After exposure of masu, and sockeye and chum salmon (Oncorhynchus keta) to M. arcticus actinospores, the penetration of sporoplasms was observed in the fins and gills of masu and sockeye salmon to a similar extent and to a lesser extent in chum salmon. Thelohanellus hovorkai actinospores exhibited a slow response of sporoplasm release to common carp mucus as well as penetration into the gills of common carp. Neither chemoresponse to mucus of nonsusceptible fish (goldfish and sockeye salmon) nor sporoplasm invasion in goldfish was observed for T. hovorkai actinospores. These results indicate notable differences in the host selection at the time of entry between M. arcticus and T. hovorkai; the former responds quickly to fish mucus with low host specificity, whereas the latter was highly host specific in a dilatory reaction.     

Surface morphology and functions of pharyngeal structures in the larval lamprey Petromyzon marinus

To gain insight into the multiple functions of a complex biological structure, the morphology of the pharynx of the larva (ammocoete) of the lamprey Petromyzon marinus was investigated with scanning electron microscopy and histochemistry (PAS and Alcian blue). Features studied include the gills, the parabranchial chambers external to the gills, intrapharyngeal ciliary tracts, the ridged pharyngeal roof, the floor, and the intrapharyngeal taste buds. Significant findings are: (1) All (nonciliated) cells lining these structures are covered with microvilli or microridges. The pattern and packing density of these membrane features vary among different pharyngeal structures. The lumenar membranes of pharyngeal lining cells overlie a mucous prosecretion in the apical cytoplasm, suggesting that the microvilli/ridges on these membranes function to anchor mucus. (2) Patterns of microvilli/ridges on the gill respiratory lamellae differ among ammocoetes of different species. (3) Pharyngeal osmo-regulatory cells (“chloride cells”) could not be identified on the basis of the microvillus/ridge pattern. (4) Two types of ciliary tracts are present within the pharynx. One has tall (x = 13 μm) and densely packed cilia, whereas the other has shorter (x = 7 μm) and less densely packed ones. Because mucus covers both types of tracts their function appears to involve the transport of mucus. (5) Food particles were found on the lateral surfaces of the gill filaments and on the surfaces of the parabranchial chambers. It appears that goblet cells in the epithelia of these regions secrete mucus in which the particles are trapped.     

Gross structure of the respiratory organs and dimensions of the gill in the mud–skipper, Periophthalmodon schlosseri (Bleeker)

In Periopkrlialnwdon scldosseri the respiratory organs consist of the gills, the suprabranchial and opercular chambers. The gills are more suited for aerial than aquatic respiration as is shown by the presence of the vascular papillae, blood sinusesand dilated blood vessels in their lamellae. The gill lamellae possess a surface coat of sulphated mucopolysaccharides that prevents water loss during exposure to the air. The filaments of the outer hemibranchs in the first gill arch are reduced to nearly one quarter of those of its posterior hemibranch. The gill area in relation to body weight shows a high slope value ( b =0·93).     

Plasticity of the scleractinian body plan: Functional morphology and trophic specialization ofMycedium elephantotus (Pallas, 1766)

Summary Morphological, histological and behavioral features indicate thatMycedium elephantotus, a zooxanthellate scleractinian species without tentacles, is well adapted for utilizing suspended organic matter for nutrition. The colonies are composed of vertically growing fan-like plates and can reach diameters of more than 1 m in depths below 20 m. The external body surface is coated with a mucus layer (cuticle) which enables the acquisition and accumulation of suspended organic material. The mucus-entangled particles pass to the mouth openings by gravitational transport assisted by water movement. In experiments the corals were able to discriminate between suspended food and mineral particles. Both types of particles were rapidly entangled in fine mucus nets or filaments. Mineral particles were never ingested and instead tumbled down the inclined skeletal plates. In contrast, food particles were actively incorporated when the mucus filaments accidentally touched the stomodaea during the downward gliding. The food-enriched mucus filaments were either transported by ciliary activity into the coelenteron or were sucked into the body cavities by decreasing pressure in the coelenteron caused by contraction of longitudinal, mesenterial muscles. The discriminative reactions to mineral or food particles are probably based on the release of different types of mucus. Nematocysts are infrequent in the oral epidermis, indicating that the capture of living prey plays a subordinate role in nutrition. The mesenterial filaments, in contrast, are densely packed with large nematocysts. Storage products were piled up within the tissues of gastral pockets. The adaptations ofMycedium elephantotus for using suspended food particles may explain the particularly high abundance of this species between ca. 20 and 40 m depth on a steeply inclined fore-reef slope in the Gulf of Aqaba (Red Sea). The evidence indicating the importance of heterotrophic fueling toM. elephantotus is supported by carbonate production rates which are, in contrast to that of many other zooxanthellate scleractinian species, almost constant at depths between 5 and 40 m and which are uneffected by varying light regimes over the year, suggesting that the reduced phototrophic contribution by the zooxanthellae is compensated by mucus suspension feeding.     

The mucous coat on gill lamellae of rainbow trout (Oncorhynchus mykiss)

The existence of a layer of mucus covering the gill lamellae of healthy rainbow trout (Oncorhynchus mykiss) was investigated. Using cryo-scanning electron microscopy, a smooth, undulating, thin layer was observed which completely covered gill filaments and lamellae, thereby obscuring epithelial microridges. After processing cryopreserved gill arches in glutaraldehyde for conventional scanning electron microscopy, the layer was no longer present and epithelial microridges were clearly visible. The identity of this layer was investigated using cryopreserved gills which were treated in one of two ways. First, gills were incubated with a rabbit antiserum to gill mucus, with normal rabbit serum, or with phosphate-buffered saline. Following fixation in glutaraldehyde and processing, only the gill tissue incubated with the mucus-specific antiserum was still covered with the smooth layer. The layer was also retained on the gills of fish anesthetized in a solution containing mucusspecific antiserum and then processes in glutaraldehyde for conventional scanning electron microscopy. The tenacious nature of the mucous layer was demonstrated by its stability following exposure to formalin and a cationic detergent. Second, the presence of this layer was confirmed on gill tissue which was cryopreserved, followed by freeze-substitution and vapor fixation, and then examined by transmission electron microscopy.     

The mucous coat on gill lamellae of rainbow trout (Oncorhynchus mykiss)

The existence of a layer of mucus covering the gill lamellae of healthy rainbow trout (Oncorhynchus mykiss) was investigated. Using cryo-scanning electron microscopy, a smooth, undulating, thin layer was observed which completely covered gill filaments and lamellae, thereby obscuring epithelial microridges. After processing cryopreserved gill arches in glutaraldehyde for conventional scanning electron microscopy, the layer was no longer present and epithelial microridges were clearly visible. The identity of this layer was investigated using cryopreserved gills which were treated in one of two ways. First, gills were incubated with a rabbit antiserum to gill mucus, with normal rabbit serum, or with phosphate-buffered saline. Following fixation in glutaraldehyde and processing, only the gill tissue incubated with the mucus-specific antiserum was still covered with the smooth layer. The layer was also retained on the gills of fish anesthetized in a solution containing mucusspecific antiserum and then processes in glutaraldehyde for conventional scanning electron microscopy. The tenacious nature of the mucous layer was demonstrated by its stability following exposure to formalin and a cationic detergent. Second, the presence of this layer was confirmed on gill tissue which was cryopreserved, followed by freeze-substitution and vapor fixation, and then examined by transmission electron microscopy.     

Electron microscopic examination of antigen uptake by salmonid gill cells after bath immunization with a bacterin

Atlantic salmon, Salmo salar , were given 2-min bath immunization with Yersinia ruckeri O-antigen bacterins at doses of 10, 100, and 1000 μg ml⁻¹. The uptake of the antigen was followed by light and electron microscopy of samples taken immediately and periodically after immunization, and the immune response monitored by the passive haemolytic plaque assay. The particulate antigen was observed in the gill mucus, adhering to and within the pavement cells covering the gill filaments, and in mononuclear phagocytes below the epidermal gill cells. There was a direct doseresponse correlation in the observed immune response according to the numbers of splenic antibody-producing cells 14 days after immunization. The cells involved in the recognition and uptake of a bacterin are initial important steps in the immune response, and these studies may aid in the immunopotentiation of fish vaccines and bacterins.     

The kinetics of accumulation and excretion of ferric hydroxide in Mytilus edulis (I.) and its distribution in the tissues

Iron, which occurs in sea water as particulate ferric hydroxide, is accumulated to high concentrations by the common mussel, Mytilus edulis (L.). The kinetics of the accumulation and excretion of iron in Mytilus has been studied using ⁵⁹Fe-labelled ferric hydroxide and the tissue distribution and identification at the sub-cellular level determined by analytical electron microscopy. Iron-59 accumulates in linear proportion to the sea-water concentration and is found in all tissues; the concentration factors for viscera, kidneys, gills, muscle = mantle is 25: 6: 4: 1, respectively. The particulate iron is taken up by pinocytosis by special epithelial cells in the gills, gut, kidney and possibly labial palps and held in membrane-bound vesicles, unaccompanied by mucus in the case of gills and kidney, but with mucus present in the digestive diverticulum and mid-gut cells. There is no free iron within the cytoplasm. Approximately 30 % of the iron presented to the gut is not absorbed being voided with the faeces. The absorbed iron is exocytosed and then passed on to amoebocytes in the haemolymph for transport to other tissues, a major portion being excreted by transfer to the byssal threads.