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141.
陈景芝 《中国微生态学杂志》2013,(9)
【摘 要】 目的 调查妊娠期女性常见阴道感染的发病情况。方法 随机选取我院孕检妇女、妇科病普查妇女各200例,采用阴道分泌物常规镜检方法对其阴道分泌物进行常规分析。结果 200妊娠期孕检妇女中,检出清洁度Ⅰ~Ⅱ 88例(占受检人数的44%)、清洁度Ⅲ~Ⅳ 112例(占受检人数的56%),阴道感染患者57例(占受检人数的28.5%),其中外阴阴道假丝酵母菌病(VVC)37例(占受检人数的18.5%)、细菌性阴道病(BV)18例(占受检人数的9%)、滴虫性阴道炎(TV)2例(占受检人数的1%);200例妇科病普查妇女中,检出清洁度Ⅰ-Ⅱ 94例(占受检人数的47%)、清洁度Ⅲ-Ⅳ 106例(占受检人数的53%)、阴道感染患者59例(占受检人数的29.5%),其中外阴阴道假丝酵母菌病(VVC)34例(占受检人数的17%)、细菌性阴道病(BV)22例(占受检人数的11%)、滴虫性阴道炎(TV)3例(占受检人数的1.5%)。经卡方检验,妊娠期孕检妇女和妇科病普查妇女中VVC、BV和TV的发病率差异均无统计学意义(P>0.05)。 结论 大兴区妊娠期女性阴道感染以VVC为主。 相似文献
142.
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145.
Nullisomic analysis of waxy (Wx) protein of hexaploid wheat (Triticum aestivum L.) cv. “Chinese Spring” using two-dimensional polyacrylamide gel electrophoresis revealed that threeWx loci,Wx-A1, Wx-B1, andWx-D1, located on chromosome arms 7AS, 4AL, and 7DS, produce three distinct Wx subunit groups, subunit group-A (SGA), SGB, and
SGD, respectively. SGA has a higher molecular weight and a more basic isoelectric point (pI) than the other two. SGB and SGD
have the same molecular weight but a slightly different pI range. Owing to the detection of these three subunit groups, we were able to identify the expression of three waxy genes
in wheat endosperm and to find two types of mutants among Japanese wheat cultivars, one lacking SGA and the others SGB. These
results suggest the possibility of breeding a waxy wheat. 相似文献
146.
Ultrastructural investigations of root caps (Zea mays) have shown a correlation between the depletion of extracellular Ca2+ resources by treatment of intact roots with 50 mM EGTA and changes in the activity of peripheral cap cells, involving reductions in the quantity and changes in the appearance of Golgi apparatus-derived material. In EGTA-treated roots the development of the Golgi apparatus of peripheral cap cells was severely altered and there was no evidence of a granular secretory product, which was encountered in the vesicles of dictyosomes of control roots. Vesicles of dictyosomes of EGTA-treated roots were small and the development of dictyosomes was reminiscent of that encountered in central cap cells of control roots. A decrease in amyloplast numbers brought about by EGTA was concomitant with reduced secretory activity. EGTA treatment was also associated with a redistribution of amyloplasts located in central cap cells. Decreased cap volume arising from EGTA treatment was considered indicative of a decline in overall cap activity. Proposals are made with regard to the integration of intercellular activities in the response of plant roots to stimulus-modulated signals. It is suggested that alterations in peripheral cap cell secretory activity arising from the redistribution of Ca2+ may account for the anisotropic growth response of gravireactive roots. 相似文献
147.
陈丽 《植物生理与分子生物学学报》1999,25(2)
在水稻蜡质基因5’上游区中一段31bp 核苷酸序列能与水稻未成熟种子核蛋白特异结合。为了克隆这一核蛋白基因,以此31 bp 序列构建成“鱼饵”质粒,从水稻cDNA文库中筛选到13 个阳性克隆。根据这些阳性克隆中插入cDNA 片段的相互杂交结果,对这些克隆进行了分组。 相似文献
148.
Richards EH 《Archives of insect biochemistry and physiology》2012,79(2):61-74
The current work demonstrates that larvae of the ectoparasitic wasp, Eulophus pennicornis, produce salivary secretions (Ep S) that contain a variety of hydrolases. This includes medium to high levels of N-acetyl-β-glucosaminidase activity, relatively low levels of esterase (C 4) and lipase (C 14) activity, and trace levels of esterase lipase (C 8), acid phosphatise, β-galactosidase, β-glucuronidase, and α-glucosidase activity. In addition, in vitro monolayer assays indicate that both a 4 h and an 18 h incubation of hemocytes from host Lacanobia oleracea larvae in Ep S significantly increases (P < 0.001) the percentage of cells dying by apoptosis compared to the controls. Moreover, an 18 h incubation of hemocytes in Ep S (but not a 4 h incubation), also significantly increased the percentage of dead cells detected using a trypan-blue exclusion assay. The role of ectoparasitoid salivary secretions in conditioning the host by disabling hemocyte-mediated wound healing responses, and providing food for the developing wasp larvae is discussed. 相似文献
149.
Trophobiont butterfly larvae offer caloric rewards to ants through specialised glands and, in return, gain ant‐derived protection from natural enemies. Thus, from the larva's perspective, the major cost of myrmecophily comprises the reward production. Larvae of the butterfly Parrhasius polibetes (Stoll) (Lycaenidae) are facultatively tended by several ant species, which might differ in the intensity of tending behaviour. The performance costs (development time, survival, pupal mass and adult dry mass) of P. polibetes are examined when tended by two ant species differing in size and foraging strategies (Camponotus melanoticus Emery and Camponotus crassus Mayr), along with the corresponding intensity of tending behaviour towards late instars. Untended larvae serve as controls. Larvae tended by C. melanoticus take longer to pupate compared with both C. crassus and control larvae. By contrast, pupae whose larvae are tended by C. crassus are lighter than control larvae but do not differ from those tended by C. melanoticus. No differences are found in the adult stage, indicating compensation in all cases. Both at short‐ and long‐term scales, C. melanoticus tends larvae of P. polibetes more intensely than C. crassus. The increase in tending activity of C. melanoticus presumably delays the development time of larvae tended by this ant species. The results of the present study show that tending intensity varies depending on the ant species, and that P. polibetes has compensatory mechanisms to minimise myrmecophily costs, regardless of tending intensity. To the authors' knowledge, this is the first experimental evidence that intensity of ant‐tending behaviour is species‐specific and affects performance in a trophobiont insect. 相似文献
150.
Summary The plant pathogenic nematodeMeloidogyne incognita forms conspicuous tubular structures referred to as feeding tubes in special food cells, called giant-cells, induced and
maintained in susceptible host roots by feeding nematodes. Feeding tubes are formed by nematode secretions injected into giant-cells
via a stylet and apparently function to facilitate withdrawal of soluble assimilates by the parasite. In giant-cells in roots
of the four host species examined in this study, feeding tube morphology was identical. Tubes were straight to slightly curved
structures just less than 1 μm wide and up to slightly more than 70 μm long. At the ultrastructural level, each tube consisted
of a 190–290 nm thick, electron-dense, crystalline wall surrounding an electron-transparent lumen with a diameter of 340–510
nm. The distal end of the tube was sealed with wall material. Older tubes were found free in the host cytoplasm while the
proximal ends of young tubes were attached to the host cell wall via short wall ingrowths through which the nematode's stylet
was inserted. An elaborate membrane system was associated with the feeding tubes and was most extensive around newly formed
tubes. Contiguous to the feeding tube wall, this membrane system consisted of strands of smooth endoplasmic reticulum while
rough endoplasmic reticulum predominated toward the outer margin of the membrane system. Vacuoles and mitochondria were excluded
from a zone of cytoplasm surrounding feeding tubes. This zone of exclusion, as well as the membrane system noted above, tended
to be less pronounced or absent around older tubes no longer being used by the nematode. 相似文献