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81.
V. Eloranta 《Protoplasma》1979,99(3):229-235
Summary The chloroplast ultrastructure ofMonoraphidium griffithii (Berkel.) Komar.-Legner. has been studied in axenic cultures of various ages. The algae have grown in a complete nutrient solution (illumination about 3,000 lx) and on its agar medium (illumination about 600 lx).The large parietal cup-shaped chloroplast of the cells includes a multiformed compound internal pyrenoid that is situated, especially in older cells, in the central part of the chloroplast opposite to the dictyosome and the nucleus. The chloroplast thylakoids either reach the edge of the pyrenoid or penetrate its matrix and run there parallel in more or less long bits. Starch grains were not found to form any sheath around the pyrenoid regions. The number of starch grains increased with the age of the cell.  相似文献   
82.
The effect of normal and immune serum on Taenia crassiceps larvae in vitro was assessed by Evans blue dye uptake and electron microscopy. Normal guinea pig, rabbit, goat, and fetal calf serum did not have any significant detrimental effects upon the larvae after 7 days of culture in vitro. Culture for 7 days in normal mouse serum resulted in some loss of tegumental microtriches but the tegument itself remained intact. Culture in hyperimmune rabbit serum resulted in complete loss of the tegument and disruption of subtegumental structures within 48 hr. The effects of immune mouse serum in vitro closely paralleled those previously seen during early immune damage in vivo. Immune serum taken 2 to 4 weeks after secondary intraperitoneal infection with T. crassiceps metacestodes caused loss of the larval tegument and degeneration of the subtegumental tissues after 7 days in culture, whereas immune mouse serum taken 6 weeks after secondary infection caused only minor ultrastructural changes and appeared to be less toxic to larvae than normal mouse serum. Although complement appeared to increase the number and severity of the tegumental lesions, the presence of heat-labile components of complement was not essential for mediation of tegumental damage by immune mouse serum.  相似文献   
83.
A new procedure is described for the purification of trophozoites from the virulent RH strain of Toxoplasma gondii propagated in baby hamster kidney (BHK-21) cell cultures. The culture medium containing host cell debris and trophozoites was filtered through glass-wool filtering fiber, which removed most host cell material. The filtrate containing trophozoites was centrifuged, and the trophozoite pellet was resuspended and washed in phosphate-buffered saline. An average of about 75% of the original number of trophozoites was recovered. No loss of trophozoite viability was observed as determined by the rate of host cell culture monolayer destruction. The amount of host cell material contamination in the final trophozoite fraction was negligible as determined by measuring radioactivity in the trophozoite fraction after cofiltration with noninfected host cell material which had been prelabeled with radioactive precursors.  相似文献   
84.
张国庆  王方  李根  任萌 《微生物学报》2022,62(11):4397-4413
【目的】在无法实现洁净环境的古建筑内,文物易遭受霉菌的破坏,尤其是在闷热的夏季。探明空气中真菌的种类对文物、游客的安全具有重要意义。【方法】采用自然沉降法与撞击法对夏季养心殿正殿内代表性的6个取样位置的气生真菌进行培养并进行ITS1 rDNA序列分析。【结果】利用自然沉降法测得气生真菌22种,以枝孢属(Cladosporium)、曲霉属(Aspergillus)和青霉属(Penicillium)为优势类群,在2个位置(佛堂二层与西暖阁)空气真菌污染超标;而撞击法测得100余种,腐生营养型真菌比例较高,优势类群为链格孢属(Alternaria)、Cladosporium、木霉属 (Trichoderma)、根霉属(Rhizopus)、AspergillusPenicillium,所有6个位置均超标。通过对环境因子与真菌多样性的相关性分析发现,养心殿内真菌丰度与温度、湿度及悬浮颗粒物有着密切关系。在相对湿度较低的6月,温度对丰度影响较大;高湿度时,悬浮颗粒物与湿度对真菌丰度影响更大。丝状真菌的丰度与小粒径悬浮颗粒物、相对湿度存在显著正相关,而空气中的酵母菌与温度相关性更高。【结论】本研究对养心殿正殿空气中真菌的种属进行了鉴定,并分析了与环境因子的相关性,为预防、开放展览以及修缮提供了科学依据。  相似文献   
85.
随着经济的发展和社会的进步,针灸推拿学科近年来发展迅速。培养优秀的针灸推拿专业人才,必须深化教育改革。本文结合教学实践,着重从目标体系、课程体系、教育教学方法体系和考核评价体系等四个方面进行了讨论:(1)从确定人才培养目标,人才培养目标体系的建立,两方面探讨构建特色专业人才培养目标体系;(2)构建以传承、实践、创新、应用为主干的核心课程体系;(3)构建课程教学与课外实践紧密结合的教育教学方法体系主要分为以下三方面工作:①实施理论课程教学改革,优化学习过程②构建与培养目标相适应的实验教学体系,加强实践创新能力培养③优化校内实训和社会实践相结合的实践教学体系,强化课外实践效果;(4)构建校内培养过程与社会认同相结合的评价体系主要分以下两个方面:①完善校内培养过程评价制度建立②培养质量的社会认同评价。  相似文献   
86.
科研能力是科学素质的核心,是运用已有的知识和科学方法去探索新的知识和方法,解决新的问题,并在这个过程中形成创新思维的能力。科学技术的创新是医学事业发展的阶梯,科技引领着医学探究生命的本质,通过对各种疾病的根源、机制、发生、后果进行研究,找到预防和治疗疾病的最佳途径,为人类解除疾病带来的痛苦。医学科技创新使医学得到快速发展的同时,为社会培养了高水平、高素质的医学人才。然而,我国的高等教育体制普遍注重教育方法的革新,而忽视学生综合素质和创新能力的培养。特别是医学高等院校,本科生的教育教学工作没有重视与科研相结合。随着高等教育体制改革的不断深入与现代科学技术的迅速发展,本科生的科研创新能力亟待进一步提高。本科生科研能力的培养已经成为当前高等教育改革的一个重要目标。本文针对医学院校本科生培养创新能力的重要性和必要性进行探讨,为医学教育的发展提供参考的资料。  相似文献   
87.
Flavobacteria are abundant in the North Sea, an epeiric sea on the continental shelf of Europe. However, this abundance has so far not been reflected by the number of strains in culture collections. In this study, Flavobacteria were isolated from pelagic and benthic samples, such as seawater, phytoplankton, sediment and its porewater, and from surfaces of animals and seaweeds on agar plates with a variety of carbon sources. Dilution cultivation with a new medium, incubation at low temperatures and with long incubation times, and colony screening by a Flavobacteria-Cytophagia-specific PCR detecting 16S rRNA gene sequences led to a collection of phylogenetically diverse strains. Two strains affiliated with Flammeovirgaceae and seven strains affiliated with Cyclobacteriaceae, whereas within the Flavobacteriaceae 20 isolated strains presumably represented seven novel candidate genera and 355 strains affiliated with 26 of 80 validly described marine Flavobacteriaceae genera, based on a genus boundary of 95.0% 16S rRNA gene sequence identity. The majority of strains (276) affiliated with 37 known species in 16 genera (based on a boundary of 98.7% 16S rRNA gene sequence identity), whereas 79 strains likely represented 42 novel species in 22 established Flavobacteriaceae genera. Pigmentation, iridescence, gliding motility, agar lysis, and flexirubin as a chemical marker supported the taxonomy at the species level. This study demonstrated the culturability on solid medium of phylogenetically diverse Flavobacteria originating from the North Sea.  相似文献   
88.
The ability of Candida bombicola ATCC 22214 to produce sophorolipids using Turkish corn oil and honey was investigated. Shake flask experiments were carried out both with and without the addition of glucose as the second carbon source. The organism could produce sophorolipids under both conditions but higher production was obtained when corn oil was combined with glucose. The 3 L bioreactor was first operated in batch mode, using both corn oil and glucose. When all the glucose was consumed, 1/4th of the broth was pumped out and was replaced by freshly prepared medium containing 10 % [w/v] of cheap market honey as the sole carbon source. Feed was comprised of corn oil. High concentrations of sophorolipids (> 400 g/L) were produced. The crude products obtained from the batch cultivation could be solidified as very light brown solids when unused oil was removed by hexane, while the products of the two‐stage cultivation remained as viscous, honey‐like liquids after identical treatments.  相似文献   
89.
Auricularia polytricha was cultivated on a sawdust basal substrate supplemented with different proportions (30%, 45%, and 60%, respectively) of stalks of three grass plants, i.e., Panicum repens (PRS), Pennisetum purpureum (PPS), and Zea mays (ZMS), to determine the most effective substrate. The mycelial growth rate, total colonization time, days to primordial formation, biological efficiency and chemical composition of fruiting bodies were evaluated. The results indicated that 30PPS was the best substrate for mycelial growth of A. polytricha, with a corresponding total colonization period of 32.0 days. With the exception of 30PPS, the total biological efficiency of all of the substrates containing P. repens stalk, P. purpureum stalk and Z. mays stalk was higher (P < 0.05) than that of the control. The most suitable substrate with a high biological efficiency was 60PRS (148.12%), followed by 30ZMS (145.05%), 45ZMS (144.15%) and 30PRS (136.68%). The nutrient values of fruiting bodies were affected by different substrates. The ash contents of A. polytricha cultivated on a substrate containing Z. mays stalk were higher than that of the control; meanwhile, the protein contents of mushroom cultivated on a substrate containing P. repens stalk (except substrate 45PRS) were higher than that of the control. The biological efficiency of the substrates was tested, and according to the results, it is feasible to use the stalks of P. repens and Z. mays on partially replaced sawdust to cultivate A. polytricha.  相似文献   
90.
为了解我国红花荷属的野生种质资源状况及其观赏价值,笔者对我国红花荷属(Rhodoleia Champ. ex Hook. f.) 6种野生种质资源进行了系统的野外调查,采集种质资源并开展了栽培试验,采用线性加权综合法,建立综合评价指标体系,对野生资源的园林开发潜力进行了评估。结果表明:红花荷、窄瓣红花荷和小花红花荷的综合价值高(Ⅰ级,分值>2.0);小脉红花荷的综合价值中等(Ⅱ级,分值1.5~2.0);绒毛红花荷和大果红花荷综合价值低(Ⅲ级,分值<1.5)。红花荷、窄瓣红花荷和小花红花荷作为优良的乡土木本花卉,在园林观赏性、栽培适应性、开发新颖性上的应用潜力非常高,值得进一步开发利用。  相似文献   
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