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101.
汉族ABO血型的皮纹特征分析 总被引:2,自引:1,他引:1
作者对芜湖地区382例(男220人;女162人)汉族ABO血型的皮纹特征进行了分析,其中O型130人,A型113人,B型101人,AB型38人。分析比较了指纹类型、指纹组合格局、指嵴纹计数、掌嵴纹计数、atd角,掌部真实花纹,掌褶纹和拇趾球纹等项参数,结果表明,ABO各血型的皮纹参数间有若干统计学差异。 相似文献
102.
P. Haffter Jörg Odenthal M. C. Mullins Shuo Lin Michael J. Farrell E. Vogelsang F. Haas M. Brand Fredericus J. M. van Eeden Makoto Furutani-Seiki Michael Granato M. Hammerschmidt Carl-Philipp Heisenberg Yun-Jin Jiang D. A. Kane R. N. Kelsh Nancy Hopkins Christiane Nüsslein-Volhard 《Development genes and evolution》1996,206(4):260-276
Mutations causing a visible phenotype in the adult serve as valuable visible genetic markers in multicellular genetic model
organisms such as Drosophila melanogaster, Caenorhabditis elegans and Arabidopsis thaliana. In a large scale screen for mutations affecting early development of the zebrafish, we identified a number of mutations
that are homozygous viable or semiviable. Here we describe viable mutations which produce visible phenotypes in the adult
fish. These predominantly affect the fins and pigmentation, but also the eyes and body length of the adult. A number of dominant
mutations caused visible phenotypes in the adult fish. Mutations in three genes, long fin, another long fin and wanda affected fin formation in the adult. Four mutations were found to cause a dominant reduction of the overall body length in
the adult. The adult pigment pattern was found to be changed by dominant mutations in wanda, asterix, obelix, leopard, salz and pfeffer. Among the recessive mutations producing visible phenotypes in the homozygous adult, a group of mutations that failed to
produce melanin was assayed for tyrosinase activity. Mutations in sandy produced embryos that failed to express tyrosinase activity. These are potentially useful for using tyrosinase as a marker
for the generation of transgenic lines of zebrafish.
Received: 17 June 1996 / Accepted: 15 July 1996 相似文献
103.
Michael Tristem Peter Kabat Elisabeth Herniou Abraham Karpas Fergal Hill 《Molecular & general genetics : MGG》1995,249(2):229-236
Despite the close similarities between retroviruses and the gypsy/Ty3 group of LTR-retrotransposons their host ranges are largely distinct: the retroviruses are found only in vertebrates, whereas the gypsy LTR-retrotransposons are almost exclusively restricted to invertebrates, plants and fungi. Here we report the amplification by PCR, and characterisation, of one of the first LTR-retrotransposons to be discovered in vertebrates - in several members of the piscine family Salmonidae. Phylogenetic analysis of this retroelement, termed easel, indicates that it is probably a phylogeneticaly basal member of the gypsy group of LTR-retrotransposons and occurs in some of the same species from which retroviruses have previously been isolated. Thus some members of the Salmonidae are the first organisms known to harbour both retroviral branch elements and the gypsy LTR-retrotransposon branch elements. This creates an overlap in the host ranges of the two retroelement families. 相似文献
104.
Between June 1986 and October 1992, in 3 periods totaling 12 months, we studied social organization of pigtailed langurs (Simias concolor)in the Pagai Islands, Indonesia. With one possible exception, all of 20 family groups contained only 1 adult male each. Nine
of them contained only 1 adult female,and 11 contained ≥2 adult females. Mean group size is 4.1 individuals. Home ranges varied from 7 to 20 ha, and population
density averages 21 animals/km
2
. Simias concoloris sexually dimorphic⤖n a museum sample males average 29% heavier than females, and their canine teeth are on average nearly
twice the length of female canines. Combined data from several studies indicate that 60% of S. concolorgroups contain an adult pair plus young,and 40% are multifemale groupings. We sggest that any 1-male mating system that comprises a mixture of 1-female and multifemale
groups in the same population should be termed monandry. 相似文献
105.
Bombesin (BBS)/gastrin-releasing peptide (GRP) binding sites were characterized and their distribution examined in the goldfish brain and pituitary by radioligand binding and autoradiography. Binding of 125I-[Tyr4]-BBS-14 to tissue sections was found to be saturable, reversible, time-dependent and displaceable by BBS/GRP-like peptides. Analysis of saturable equilibrium binding revealed a one-site model fit with a Kd of 0.665 ± 0.267 nM. This binding site displayed high affinity for members of the BBS subfamily of peptides, including GRP10 (Ki; 0.292 ± 0.038 nM) and GRP27 (Ki; 2.034 ± 1.597 nM), but showed no affinity for the BBS8–14 fragment. While an approximate 100-fold lower binding affinity was displayed by the binding site for neuromedin B (Ki; 61.5 ± 28.2 nM), litorin was highly effective in displacing radiolabeled BBS binding (Ki; 1.469 ± 0.427 nM). The localization of saturable and high affinity BBS/GRP binding sites in specific areas of the goldfish brain and pituitary generally revealed a similar anatomical distribution to BBS/GRP-like immunoreactive material reported previously by our laboratory. Quantitative densitometric analysis of radiolabeled BBS binding to brain nuclei and the pituitary revealed a moderate concentration of BBS/GRP binding sites in the hypothalamic feeding area, including the nucleus diffusus lobi inferioris, nucleus recessus lateralis, nucleus lateral tuberis, and nucleus anterior tuberis. Other brain nuclei known to influence the brain feeding center which contained a high density of BBS/GRP binding sites included nuclei of the dorsal and ventro-medial telencephalon, the preoptic hypothalamus, and the optic tectum. High densities of BBS/GRP binding sites were also localized in the dorsal cerebellum, and nucleus habenularis. In the pituitary, BBS/GRP binding sites were present in high concentration in the neurointermediate lobe, with a relatively lower density localized in the pars distalis. The present study further supports a role for BBS/GRP-like peptides in the regulation of feeding behavior and anterior pituitary hormone secretion in teleosts. 相似文献
106.
Summary In homospecific groups of ants, each species has its own hydrocarbon profile, on the epicuticle and in the postpharyngeal gland (PPG). When reared together in bispecific groups, workers of both species possess each other's hydrocarbons in both locations. The present study investigated two alternative mechanisms by which a mixed odour in artificial groups ofFormica selysi/Manica rubida can be created. Using [1-14C] sodium acetate as a precursor,de novo biosynthesis of hydrocarbons was demonstrated for both species whether reared in homospecific or mixed-species groups. The newly synthesized hydrocarbons occurred on the epicuticle, internally, and in particularly large amounts in the PPG. As expected from their PPG and epicuticular hydrocarbons composition, workersF. selysi synthesized alkanes and alkenes in comparable amounts irrespective of their rearing scheme. Likewise,M. rubida reared in bispecific groups synthesized mostly alkanes with only negligible amounts of alkenes, according to a ratio characteristic toM. rubida workers from homospecific groups and not toF. selysi workers. During dyadic encounters, a transfer of labeled hydrocarbons between nestmates (conspecific in homospecific groups and allospecific in mixed groups) was observed. These results suggest that the formation of the mixed hydrocarbon profile in artificial groups of ants is the result of a transfer of these chemicals between nestmates rather thande novo biosynthesis of the allospecific hydrocarbons. Behaviours like trophallaxis, grooming and body contact that occurred during the encounters mediated such a transfer. 相似文献
107.
Structure and evolution of teleost mitochondrial control regions 总被引:50,自引:0,他引:50
Woo-Jai Lee Janet Conroy W. Huntting Howell Thomas D. Kocher 《Journal of molecular evolution》1995,41(1):54-66
We amplified and sequenced the mitochondrial control region from 23 species representing six families of teleost fish. The length of this segment is highly variable among even closely related species due to the presence of tandemly repeated sequences and large insertions. The position of the repetitive sequences suggests that they arise during replication both near the origin of replication and at the site of termination of the D-loop strand. Many of the conserved sequence blocks (CSBs) observed in mammals are also found among fish. In particular, the mammalian CSB-D is present in all of the fish species studied. Study of potential secondary structures of RNAs from the conserved regions provides little insight into the functional constraints on these regions. The variable structure of these control regions suggests that particular care should be taken to identify the most appropriate segment for studies of intraspecific variation.
Correspondence to: T.D. Kocher 相似文献
108.
Spectroscopic techniques were used to investigate the interaction between vanadate and human erythrocyte ghosts. Direct evidence from 51V nuclear magnetic resonance (NMR) studies suggested that the monomeric and polymeric vanadate species may bind to the anion binding sites of band 3 protein of the erythrocyte membrane. The results of 51V NMR studies and the quenching effect of vanadate on the intrinsic fluorescence of the membrane proteins indicated that in the low concentration range of vanadate (<0.6 mm), monomeric vanadate binds mostly to the anion sites of band 3 protein with the dissociation constant close to 0.23 mm. The experiments of sulfhydryl content titration by the method of Ellman and residue sulfhydryl-labeled fluorescence spectroscopies clearly displayed that vanadate reacts directly with sulfhydryl groups. The appearance of the anisotropic election spin resonance (ESR) signal of vanadyl suggests that a small (c. 3%) amount of vanadate was reduced by sulfhydryl groups of membrane proteins. The fluidity and order of intact ghost membrane were reduced by the reaction with vanadate, as shown by the ESR studies employing the protein- and lipid-specific spin labels. It was concluded that although vanadates mainly bind to band 3 protein, a minor part of vanadate may oxidize the residue sulfhydryl groups of membrane proteins, and thus decrease the fluidity of erythrocyte membrane. 相似文献
109.
利用Oligo1000DNA合成仪(Beckman)合成了长度为45bp的寡核苷酸单链,经纯化后用同位素γ-32P-ATP作5′末端标记后,制备成鱼类LZF-IDNA指纹探针。通过对鱼类的群体实验、亲子鉴定实验、组织细胞的稳定性实验和鱼类种类的适用范围实验后,测得:(1)LZF-IDNA指纹探针属多位点寡核苷酸探针;(2)LZF-IDNA指纹探针在鱼类种群中的鉴别机率为9.23×10-16;(3)LZF-IDNA指纹探针在鱼类亲子鉴定实验中的父系概率为0.999962;(4)LZF-IDNA指纹探针,是一种稳定的,既具有个体识别能力,又具有一定种属特异性的、适用于鱼类DNA指纹图研究的基因指纹探针。 相似文献
110.
G. Ramírez-Zarzosa F. Gil R. Latorre A. Ortega A. García-Alcaráz E. Abellán J. M. Vázquez O. López-Albors A. Arencibia F. Moreno 《Cell and tissue research》1995,280(2):217-224
Fibre-type differentiation of the lateral musculature has been studied in Sparus aurata (L.) and Dicentrarchus labrax (L.) during larval development. Histochemical and ultrastructural techniques show two presumptive muscle layers and two germinative zones of presumptive myoblasts. At hatching, myotomal muscle consists of a monolayer of thin undifferentiated cells near the skin (first germinative zone) overlying another mono-layer of small diameter fibres extending hypaxially and epaxially away from the transverse septum. Below this, there is a much thicker, deep layer of fibres, generally large in diameter and polygonal in shape. The presumptive myoblasts are located between these two layers of fibres in the second germinative zone. Initially, the superficial and deep muscle fibres show high and low myosin ATPase activity, respectively. Both layers grow by generating new fibres from the two mentioned germinative zones. At the end of larval life, the superficial layer changes its histochemical profile from high to low myosin ATPase activity and, at the same time, intermediate or pink muscle fibres can be observed by oxidative activity (the NADH-TR reaction). Morphometric analysis shows a significant increase in mean fibre diameter during successive ages, as shown by the Student's t-test (hypertrophic growth). Skewness and kurtosis values of fibre diameters point to the generation of a new fibre population from the germinative zones (hyperplastic growth). 相似文献