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811.
Harris Pratsinis Angelica Saetta Sarantis Gagos Panayiotis Davaris 《In vitro cellular & developmental biology. Animal》1998,34(9):722-728
Summary A novel continuous cell line, designated BC3c, was established from a surgical biopsy of an invasive solid transitional cell
carcinoma of the bladder derived from an 82-yr-old Caucasian female. BC3c cells were near-triploid bearing multiple structural
and numerical chromosome anomalies. The epithelial origin of the cancer cells was indicated by the expression of cytokeratins
8 and 19 as well as by the absence of mesenchymal markers. Polymerase chain reaction-restriction-fragment length polymorphisms
and single-strand conformation polymorphism mutation detection assays did not reveal any mutations in H-ras codon 12 and K-ras codons 12 and 13. In addition, no mutation in specific hot-spot codons of the p53 gene and no accumulation of the p53 protein were observed. BC3c cells grew rapidly in vitro, even in the absence of exogenous growth factors, because they were found to stimulate their growth in an autocrine manner.
BC3c cells were found to express the epidermal growth factor-receptor (EGF-r) abundantly, but in contrast to other established
bladder cancer cell lines, human recombinant epidermal growth factor inhibited the cells’ proliferation in vitro. These features render the newly established bladder cancer cell line BC3c a useful tool for further experimentation. 相似文献
812.
Joan H. Schiller Gerard Bittner Shi-Qi Wu Lorraine Meisner 《In vitro cellular & developmental biology. Animal》1998,34(4):283-289
Summary In this study, we describe the karyotypic changes associated with the spontaneous acquisition of tumorigenicity in an immortalized
tumor bronchial cell line. Neoplastic transformation of the NL20 human bronchial epithelial cell line occurred after 3 yr
in culture, and was associated with loss of chromosome 18 together with acquisition of multiple copies of 9q21.2→34. The nontumorigenic
NL20 cell line had been established by transfection of human bronchial epithelial cells with the SV40 T antigen, and had retained
a relatively stable karyotype after the first 32 passages in vitro. However, when cells from p184 were inoculated into nude mice, a transplantable tumor was obtained that was derived from
a minor clone present in this otherwise stable line. Subsequent passaging of the NL20 cells in vitro did not yield further tumors, and the minor clone from which the tumorigenic NL20T cell line derived was no longer evident
in NL20 cells by Passage 205. Furthermore, the original tumorigenic NL20T cells lost the neoplastic phenotype after 25 passages
in vitro and reverted to the nontumorigenic karyotype observed at p189. In contrast to the loss of the tumorigenic phenotype and karyotype,
which occurred with in vitro passaging of the original tumor, when the NL20T cells were passaged in other nude mice, they continued to give rise to tumors
with sevenfold amplifications of 9q sequences and loss of chromosome 18, and cells from the secondary tumors (NL20T-A cells)
have maintained a stable karyotype and remain tumorigenic even after 64 passages in vitro. A mixture of 10% tumorigenic NL20T-A and 90% nontumorigenic NL20 cells formed tumors in athymic nude mice when cultured
in vitro on fibronectin, but not on plastic; cytogenetic analysis demonstrated that the tumors and cell cultures were composed of
tumorigenic NL20T-A cells, whereas cytogenetic analysis of cells cultured on plastic were identical to the nontumorigenic
NL20 cells. These data support the hypothesis that neoplastic transformation in our original cell line arose from in vivo selection of a small mutant clone, which had arisen in culture and was subsequently selected in vivo but was lost with in vitro culture. 相似文献
813.
C Klein L J Ozelius J Hagenah X O Breakefield N J Risch P Vieregge 《American journal of human genetics》1998,63(6):1777-1782
Both the discovery of the DYT1 gene on chromosome 9q34 in autosomal dominant early-onset torsion dystonia and the detection of linkage for one form of adult-onset focal dystonia to chromosome 18p (DYT7) in a family from northern Germany provide the opportunity to further investigate genetic factors in the focal dystonias. Additionally, reports of linkage disequilibrium between several chromosome 18 markers and focal dystonia, both in sporadic patients from northern Germany and in members of affected families from central Europe suggest the existence of a founder mutation underlying focal dystonia in this population. To evaluate the role of these loci in focal dystonia, we tested 85 patients from northern Germany who had primary focal dystonia, both for the GAG deletion in the DYT1 gene on chromosome 9q34 and for linkage disequilibrium at the chromosome 18p markers D18S1105, D18S1098, D18S481, and D18S54. None of these patients had the GAG deletion in the DYT1 gene. Furthermore, Hardy-Weinberg analysis of markers on 18p in our patient population and in 85 control subjects from the same region did not support linkage disequilibrium. Taken together, these results suggest that most cases of focal dystonia in patients of northern German or central European origin are due neither to the GAG deletion in DYT1 nor to a proposed founder mutation on chromosome 18p but must be caused by other genetic or environmental factors. 相似文献
814.
Linkage of familial Hibernian fever to chromosome 12p13. 总被引:2,自引:0,他引:2
M F McDermott B W Ogunkolade E M McDermott L C Jones Y Wan K A Quane J McCarthy M Phelan M G Molloy R J Powell C I Amos G A Hitman 《American journal of human genetics》1998,62(6):1446-1451
Autosomal dominant periodic fevers are characterized by intermittent febrile attacks of unknown etiology and by recurrent abdominal pains. The biochemical and molecular bases of all autosomal dominant periodic fevers are unknown, and only familial Hibernian fever (FHF) has been described as a distinct clinical entity. FHF has been reported in three families-the original Irish-Scottish family and two Irish families with similar clinical features. We have undertaken a genomewide search in these families and report significant multipoint LOD scores between the disease and markers on chromosome 12p13. Cumulative multipoint linkage analyses indicate that an FHF gene is likely to be located in an 8-cM interval between D12S77 and D12S356, with a maximum LOD score (Z max) of 3.79. The two-point Z max was 3.11, for D12S77. There was no evidence of genetic heterogeneity in these three families; it is proposed that these markers should be tested in other families, of different background, that have autosomal dominant periodic fever, as a prelude to identification of the FHF-susceptibility gene. 相似文献
815.
An intergeneric somatic hybrid was obtained upon fusion of protoplasts of rice and barley. Protoplasts isolated from suspension
cultures of rice cells were fused by electrofusion with protoplasts that had been isolated from young barley leaves. Some
of the resultant calli formed green spots and shoots. Only one shoot formed roots, and it was subsequently successfully transferred
to soil in a greenhouse. Its morphology closely resembled that of the parental rice plant. Cytological analysis indicated
that the plant had both small chromosomes from rice and large chromosomes from barley. Southern hybridization analysis with
a fragment of the tryptophan B (trpB) gene revealed both a rice-specific band and a barley-specific band. Mitochondrial (mt) and chloroplast (cp) DNAs were also analyzed using the same method. The plant was shown to contain novel mitochondrial and chloroplast sequence
rearrangements that were not detected in either of the parents.
Received: 5 March 1997 / Revision received: 4 September 1997 / Accepted: 13 September 1997 相似文献
816.
Somatic hybrids were obtained by polyethylene glycol fusion of cotyledon protoplasts of Lycopersicon esculentum Mill. cv. Kyoryokutoko treated with iodoacetamide (IOA) and suspension-culture-derived protoplasts of L. peruvianum (PI270435) or L. chilense (PI128652). The hybrids were selected by a multiple-step selection procedure relying on the different colors of the fusion
partners, IOA treatment of cotyledon protoplasts, and the use of a culture medium which only allowed cotyledon protoplasts
to regenerate. The somatic embryos were derived from greenish calli that formed from the fusion mixtures, developed progressively
through the globular, heart, and torpedo stages, and finally formed complete plantlets. The excised torpedo-stage embryos
could be propagated on a modified medium. The morphology of the somatic hybrids were intermediate to their donor partners,
and chromosome observations indicated that the hybrids were tetraploid, hexaploid, and aneuploid.
Received: 24 July 1997 / Revision received: 4 November 1997 / Accepted: 2 December 1997 相似文献
817.
显微分离出黑麦(SecalecerealeL.)1R染色体,用CohesiveadapterssingleprimerPCR(CASPPCR)方法进行体外扩增,以DIG11dUTP标记扩增产物为探针,进行Southern分子杂交,结果表明扩增产物来自黑麦1R染色体。用1/10体积的连接物转化E.coliDH5α,获得10000多个重组菌落。经酶切分析,克隆子的插入片段为250~500bp,为进一步筛选1R染色体的分子标记打下了基础 相似文献
818.
安徽石蒜属4种植物核型研究 总被引:15,自引:0,他引:15
本文分析了安徽境内石蒜属LycorisHerb.4种植物的核型,并结合有关文献探讨它们的核型变异。结果表明,乳白石蒜L.albifoliaKoidz.的核型为2n=19=3m+7st+4t+5T,属3B型;中国石蒜L.chinensisTraub.为2n=16=6m+10T,属3B型;石蒜L.radiata(L’Her.)Herb.为2n=22=4st+18t,属4A型;换锦花L.sprengeriComes.exBaker.为2n=22=2st+20t,属4A型。以上各种植物均未发现随体和次缢痕,通过核型比较,可见同种不同居群间在染色体数和核型结构上均存在较大的变异。 相似文献
819.
820.
D. Peltier E. Farcy H. Dulieu A. Bervillé 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,88(6-7):637-645
We have established the first linkage map forPetunia hybrida based upon both RAPD and phenotypical markers. The progeny studied consisted of 100 BC1 individuals derived from the [(St40xTlvl)xTlvl] back-cross. Each morphological marker has previously been mapped onto one of the seven chromosomes. The map consists of 35 RAPD loci of which 24 were affected onto chromosomes while 10 loci were not affected. The loci covered 262.9 cM with a mean distance of 8.2 cM. They are dispersed over seven linkage groups, of which six are carried on identified chromosomes. The RAPD markers were also applied on a set of tenP. hybrida, lines chosen for their diversity and on a set of seven wild species corresponding to the possible ancestors of theP. hybrida species. The markers were found both in the wild species as well as inP. hybrida lines indicating that they are inherited and are stable enough to establish similarities and to suggest relationships between species. Eight out of the ten lines carry different linkage groups of RAPD markers, which suggest that recombinant events occurred between chromosomes which originated in the wild species. 相似文献