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941.
在春季田间条件下,我们对美味猕猴桃品种米良1 号(Actinidia deliciosa cvMiliang-1)的光-光合特性与净光合速率日变化及其与环境因子的关系进行了初步研究.结果表明美味猕猴桃米良1 号在适宜的环境条件下(气温34 ℃,相对湿度62% ),同化CO2 的光合速率达到17.37~18.69 μm olm - 2s- 1,但是在高温和干旱条件下(气温41℃,相对湿度30% ),其光合能力降低到7.32 μm olm - 2s- 1.该品种的光饱和点与光补偿点分别为1 100 和20 μm olm - 2s- 1, 表明是一种阴性偏阳的树种. 5 月初的晴天,美味猕猴桃米良1号的净光合速率日变化呈双峰曲线型,第一高峰出现在上午10∶00,18.65 μm olm - 2s- 1,午间13∶00 剧降到3.15 μm olm - 2s- 1,下午16∶00 出现第二高峰,其值为10.35 μm olm - 2s- 1. 在测定净光合速率的同时,还对田间条件下环境因子如光照、气温、空气湿度与CO2浓度以及植物叶表面温度与蒸腾速率日变化等进行了监测,用多元线形回归的方法分析了环境因子对猕猴桃光合作用日变化的影响 相似文献
942.
943.
原癌基因c-myc是普遍存在于动物组织中的一个高度保守的细胞凋亡相关基因,决定着多种动物细胞的凋亡。我们首次以人c-myc的基因组DNA为探针,用生物素标记的原位杂交和酶联级联放大检测系统在玉米中检出了c-myc基因的同源序列,并对其进行了染色体物理定位。在第5染色体长臂近末端、第4染色体长臂近着丝粒及第1染色体短臂近着丝粒处检测到杂交信号,信号与着丝粒的百分距离分别为96.21±4.46、24.11±0.47和10.02±1.04,本结果为寻找和研究植物细胞凋亡基因提供了重要线索。 相似文献
944.
Plant regeneration from Rosa shoot tips cryopreserved by a combined droplet vitrification method 总被引:1,自引:0,他引:1
Shoot tips obtained from in vitro Rosa plants (three cultivars) were successfully cryopreserved by a combined droplet vitrification method and subsequently shoots
regenerated. The excised shoot tips (1–4 mm long) were incubated in a liquid MS medium supplemented with 2.5 mg l−1 thiamine, 0.2 mg l−1 biotin, 0.2 mg l−1 pyridoxine, 0.25 mg l−1 6-benzylaminopurine (BAP), 0.5 mg l−1 gibberellic acid (GA3) and 0.08 M sucrose, for 24 h. Following that incubation shoot tips were pre-cultured in this MS medium containing 0.1 till
1.0 M sucrose for 24 and 48 h, respectively. Pre-cultured shoot tips were dehydrated with concentrated PVS2 cryoprotective
solution for 10–30 min at room temperature, prior to a direct plunge in liquid nitrogen. After rapid rewarming in the above
mentioned liquid medium shoot tips were plated on a modified MS medium (5 g l−1 agar) supplemented with vitamins and plant growth regulators as mentioned above for regrowth. Cryopreserved shoot tips resumed
growth within 10 days and regenerated shoots within 3 weeks. The highest numbers of regrowing shoot tips were 64.44% for cv.
Kardinal, 67.73% for cv. Fairy and 57.57% for cv. Maidy. 相似文献
945.
Lavalette D Hink MA Tourbez M Tétreau C Visser AJ 《European biophysics journal : EBJ》2006,35(6):517-522
Translational and rotational diffusion coefficients of proteins in solution strongly deviate from the Stokes–Einstein laws when the ambient viscosity is induced by macromolecular co-solutes rather than by a solvent of negligible size as was assumed by A. Einstein one century ago for deriving the laws of Brownian motion and diffusion. Rotational and translational motions experience different micro viscosities and both become a function of the size ratio of protein and macromolecular co-solute. Possible consequences upon fluorescence spectroscopy observations of diffusing proteins within living cells are discussed. 相似文献
946.
Lima-Brito J Carvalho A Martin A Heslop-Harrison JS Guedes-Pinto H 《Journal of genetics》2006,85(2):123-131
The morphological, yield, cytological and molecular characteristics of bread wheat X tritordeum F1 hybrids (2n =6x = 42; AABBDHch) and their parents were analysed. Morphologically, these hybrids resembled the wheat parent. They were slightly bigger than
both parents, had more spikelets per spike, and tillered more profusely. The hybrids are self-fertile but a reduction of average
values of yield parameters was observed. For the cytological approach we used a double-target fluorescencein situ hybridization performed with total genomic DNA fromHordeum chilense L. and the ribosomal sequence pTa71. This technique allowed us to confirm the hybrid nature and to analyse chromosome pairing
in this material. Our results showed that the expected complete homologous pairing (14 bivalents plus 14 univalents) was only
observed in 9.59% of the pollen mother cells (PMCs) analysed. Some PMCs presented autosyndetic pairing of Hch and A, B or
D chromosomes. The average number of univalents was higher in the wheat genome (6.8) than in the Hch genome (5.4). The maximum
number of univalents per PMC was 20. We only observed wheat multivalents (one per PMC) but the frequency of trivalents (0.08)
was higher than that of quadrivalents (0.058). We amplified 50 RAPD bands polymorphic between the F1 hybrid and one of its parents, and 31 ISSR polymorphic bands. Both sets of markers proved to be reliable for DNA fingerprinting.
The complementary use of morphological and yield analysis, molecular cytogenetic techniques and molecular markers allowed
a more accurate evaluation and characterization of the hybrids analysed here. 相似文献
947.
Nenad Bukvic Carla CesaranoCaterina Ceccarini Marianna BrunoMaria Rosaria Lipsi Maria Grazia GallicchioMaria Assunta Carboni Lucia ValenteGiulia Cotoia Raffaele Antonetti 《Gene》2013
Herein, we describe a case of an infertile man detected in postnatal diagnosis with FISH characterization and array-CGH used for genome-wide screening which allowed the identification of a complex rearrangement involving sex chromosomes, apparently without severe phenotypic consequences. The deletion detected in our patient has been compared with previously reported cases leading us to propose a hypothetical diagnostic algorithm that would be useful in similar clinical situations, with imperative multi disciplinary approach integrated with genetic counseling. Our patient, uniquely of reproductive age, is one of six reported cases of duplication of Xp22.3 (~ 8.4 Mb) segment and contemporary deletion of Yq (~ 42.9 Mb) with final karyotype as follows:
- 46,X,der(Y),t(X;Y)(Ypter → Yq11.221::Xp22.33 → Xpter).ish der(Y) (Yptel+,Ycen+,RP11-529I21+,RP11-506M9-Yqtel −,Xptel +). arrXp22.33p22.31(702–8,395,963, 8,408,289x1), Yq11.221q12 (14,569,317x1, 14,587,321–57,440,839x0) 相似文献
948.
Pauline Gaignard Jérôme Fagart Natalia Niemir Jean-Philippe Puech Emilie Azouguene Jeanne Dussau Catherine Caillaud 《Gene》2013
Sandhoff disease (SD) is an autosomal recessive lysosomal storage disease caused by mutations in the HEXB gene encoding the beta subunit of hexosaminidases A and B, two enzymes involved in GM2 ganglioside degradation. Eleven French Sandhoff patients with infantile or juvenile forms of the disease were completely characterized using sequencing of the HEXB gene. A specific procedure was developed to facilitate the detection of the common 5′-end 16 kb deletion which was frequent (36% of the alleles) in our study. Eleven other disease-causing mutations were found, among which four have previously been reported (c.850C>T, c.793T>G, c.115del and c.800_817del). Seven mutations were completely novel and were analyzed using molecular modelling. Two deletions (c.176del and c.1058_1060del), a duplication (c.1485_1487dup) and a nonsense mutation (c.552T>G) were predicted to strongly alter the enzyme spatial organization. The splice mutation c.558+5G>A affecting the intron 4 consensus splice site led to a skipping of exon 4 and to a truncated protein (p.191X). Two missense mutations were found among the patients studied. The c.448A>C mutation was probably a severe mutation as it was present in association with the known c.793T>G in an infantile form of Sandhoff disease and as it significantly modified the N-terminal domain structure of the protein. The c.171G>C mutation resulting in a p.W57C amino acid substitution in the N-terminal region is probably less drastic than the other abnormalities as it was present in a juvenile patient in association with the c.176del. Finally, this study reports a rapid detection of the Sandhoff disease-causing alleles facilitating genetic counselling and prenatal diagnosis in at-risk families. 相似文献
949.
Inesse Ben-Abdallah-Bouhjar Soumya Mougou-Zerelli Hanene Hannachi Hela Ben-Khelifa Najla Soyah Audrey Labalme Damien Sanlaville Hatem Elghezal Ali Saad 《Gene》2013
Partial duplication of 11q is related to several malformations like growth retardation, intellectual disability, hypoplasia of corpus callosum, short nose, palate defects, cardiac, urinary tract abnormalities and neural tube defects. We have studied the clinical and molecular characteristics of a patient with severe intellectual disabilities, dysmorphic features, congenital inguinal hernia and congenital cerebral malformation which is referred to as cytogenetic exploration. We have used FISH and array CGH analysis for a better understanding of the double chromosomic aberration involving a 7p microdeletion along with a partial duplication of 11q due to adjacent segregation of a paternal reciprocal translocation t(7;11)(p22;q21) revealed after banding analysis. The patient's karyotype formula was: 46,XY,der(7)t(7;11)(p22;q21)pat. FISH study confirmed these rearrangement and array CGH technique showed precisely the loss of at least 140 Kb on chromosome7p22.3pter and 33.4 Mb on chromosome11q22.1q25. Dysmorphic features, severe intellectual disability and brain malformations could result from the 11q22.1q25 trisomy. Our study provides an additional case for better understanding and delineating the partial duplication 11q. 相似文献
950.
Nm23 is a family of genes encoding the nucleoside diphosphate (NDP) kinase, which functions in a wide variety of biological processes, including growth, development, differentiation and tumor metastasis. In this study, a novel nm23 gene, designated as Mrnm23, was identified from the freshwater giant prawn Macrobrachium rosenbergii. The full-length cDNA was 776 bp in length, encoding for a protein of 176 amino acids with one typical NDP kinase domain that harbored all the crucial residues for nucleotide binding and enzymatic activity. Like human novel nm23-H1B, the putative protein contained a unique 21-amino-acid NH2-terminal extension as compared to human nm23 (nm23-H1) homologs. Further, 3 extra amino acid residues prolonged the COOH-terminus. The Mrnm23 was ubiquitously expressed in all tissues examined, including androgenic gland, gill, heart, liver, muscle, ovary, and testis. In situ hybridization to gonad sections indicated that the Mrnm23 mRNA was localized in the cytoplasm of cup-base of differentiating spermatids, in the spike of the umbrella-shaped spermatozoa and in the cytoplasm of the early previtellogenic oocytes, suggesting that the Mrnm23 has potential roles in spermiogenesis and early differentiation of oocyte. 相似文献