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131.
132.
从手术切除的24例女性和12例男性尖锐湿疣新鲜标本中,以及42例女性尖锐湿疣、16例男性外耳道乳头状瘤和4例女性假性湿疣的石蜡包埋标本中,提取组织的基因组DNA,用人工合成的人乳头瘤病毒6.11和16型E6区特异性寡聚核苷酸引物,通过PCR进行HPV DNA的分型检测。结果66例女性尖锐湿疣中,感染HPV6型者4例,感染11型者12例,6+11型混合感染者49例;阴性1例,总检出率达98.4%。4例女性假性湿疣中1例为HPV6型感染,阳性率25%。16例男性外耳道乳头状瘤中HPV6+11型感染者5例,6+16型感染者3例,6+11+16型多重感染者8例,阳性率100%。12例男性尖锐湿疣中,HPV11型感染者7例,6+11型4例,阴性1例,总阳性率91.6%。还对细胞学上空泡化和非典型空泡化尖锐湿疣标本的HPV感染做了比较,未发现差异。 相似文献
133.
J. R. Beddington C. A. Mills †† F. Beards ‡ M. J. Minski ‡ J. N. B. Bell ‡ 《Journal of fish biology》1989,35(5):679-686
It proved possible to determine the levels of Sr-90 in the opercular bones of individual pike, Esox Iucius , and in pooled samples of bones from perch, Perca fluviatilis . Results from both species from Windermere demonstrated that Sr-90 levels rose from below the detection limits in the 1940s to a peak in the 1960s, followed by a decline in the subsequent two decades. This decline was slower than would have been expected from the decline in northern hemisphere Sr-90 fallout, indicating the likelihood of recycling within the environment. Sr-90 levels were consistently lower in pike than in perch, their main prey fish. Thus, there is no concentration of Sr-90 up this part of the aquatic food chain. Tracking Sr-90 in bones taken in successive years from ages 3 to 8 for a single cohort of pike showed that the quantity of Sr-90 was closely related to opercular bone (and hence fish) weight. No significant increase in Sr-90 concentration in the bone with increasing age was demonstrated. 相似文献
134.
Marion Baur A.J. Meyer H.-G. Heumann M. Lützelschwab W. Michalke 《Plant biology (Stuttgart, Germany)》1996,109(5):382-387
The proton pumping ATPase in the plasma membrane of Elodea canadensis is believed to play a major role in inorganic carbon acquisition. To investigate potentially different carbon uptake strategies within the same plant, plasma membrane H+-ATPase distribution and polar current patterns were investigated in Elodea leaves and stems. Specific activity of plasma membrane H+-ATPase in leaf microsomal fractions was tenfold higher than in stem derived microsomes. Probing western blots with a monoclonal antibody specific for plasma membrane H+-ATPase, yielded strongly visible double bands at 100 kDa in leaf microsome preparations, whereas little antigen was detected in analogous stem microsome preparations. Using the same plasma membrane H+-ATPase specific antibody on tissue sections, the enzyme was found almost exclusively localized at the border of cells at the lower leaf surface. A positive ion current leaving the lower leaf surface was measured, using a vibrating probe device. Part of this current entered the upper leaf surface and part of it the internodes of the stem. The experimental results support the view, that Elodea leaves have different means of inorganic carbon uptake than stem internodes. 相似文献
135.
Giuseppe Comi Corrado Pipan Giuseppe Botta Luca Cocolin Carlo Cantoni Marisa Manzano 《FEMS immunology and medical microbiology》1996,16(1):45-49
Abstract A combined polymerase chain reaction and restriction endonuclease (RE) enzyme assay was developed to discriminate between Campylobacter coli and Campylobacter jejuni . Amplimers of the FlaA gene obtained by PCR were digested with Alu I and Hin fI to distinguish C. coli from C. jejuni . With Alu I digestion C. jejuni -specific bands were observed at 110, 140 and 160 bp and C. coli -specific bands at 293 and 147 bp. C. jejuni -specific bands of 349 and 109 bp were found by Hin fI digestion but Hin fI did not digest the Fla A amplimer of C. coli . This combined technique is fast and easy to perform, and distinguishes the two campylobacters unequivocally. 相似文献
136.
Rapid typing of truffle mycorrhizal roots by PCR amplification of the ribosomal DNA spacers 总被引:4,自引:0,他引:4
DNA analyses were developed to type mycorrhizas of two Tuber species of commercial value (T. melanosporum, T. borchii) and a competitive fungus (Sphaerosporella brunnea) which forms ectomycorrhizas with plants usually considered hosts for truffles. Polymerase chain reaction (PCR) amplification
of DNA isolated from fruitbodies, mycelia, mycorrhizas and leaves of host plants, was performed with a primer pair for an
internal transcribed spacer ITS1-4. ITS amplification followed by restriction fragment length polymorphism (RFLP) analysis
of the amplified products clearly distinguished the two Tuber species at the fruitbody, mycorrhiza and mycelium levels.
Accepted: 6 September 1996 相似文献
137.
质体非均衡分裂时,其传递和分配情况复杂,重组状态多。本文分析了突变质体在各种分配情况下得到的概率,条件概率、联合概率和一细胞至少含m_0个突变质体的概率公式及计算示例。讨论了它们在生物学中的重要意义。 相似文献
138.
EB病毒胸苷激酶基因的扩增 总被引:1,自引:0,他引:1
EB病毒胸苷激酶基因的扩增陈尚武,陈瑞君,黄迪,朱振宇,马涧泉(中山医科大学生化教研室,广州510089)(中山医科大学肿瘤研究所,广州510060)关键词Epstein-Barr病毒,胸苷激酶,基因,聚合酶链反应鼻咽癌(nasopharyngeal... 相似文献
139.
Balzer Sandrock Karen M. Hudson Douglas E. Williams Michael A. Lieberman 《In vitro cellular & developmental biology. Animal》1996,32(4):225-233
Summary The regulation of megakaryopoeisis by cytokines is not yet well understood. It is possible that autocrine loops are established
during megakaryocyte growth and differentiation, aiding in the maturation of these cells. The CHRF-288-11 human megakaryoblastic
cell line has been examined for cytokine production in growing cells and cells stimulated to differentiate by the addition
of phorbol esters. It has been demonstrated that these cells produce RNA corresponding to the interleukins IL-1α, 1β, 3, 7,
8, and 11, granulocyte-macrophage colony stimulating factor (GM-CSF), stem cell factor (SCF), transforming growth factor-β
(TGF-β), tumor necrosis factor-α (TNF-α), interferon-α (INF-α), and basic fibroblast growth factor (bFGF). Additionaly, RNA
corresponding to the receptors for IL-6, GM-CSF, SCF, INF-α,β, bFGF, and monocyte colony stimulating factor (M-CSF) were also
expressed by the cells. The receptor for TNF-α was detected immunologically. Analysis at the protein level demonstrated that
significant amounts of INF-α, TNF-α, GM-CSF, SCF, IL-1α, and a soluble form of the IL-6 receptor were produced by the cells.
Addition of phorbol esters to CHRF-288-11 cells enhances their megakaryocytic phenotype; such treatment also results in increased
secretion of INF-α, TNF-α, and GM-CSF. These results suggest that potential autocrine loops are established during the differentiation
of CHRF-288-11 cells, which may alter the capability of the cell to differentiate. These findings are similar to those recently
obtained for marrow-derived megakaryocytes (Jiang et al.) suggesting that CHRF-288-11 cells provide a useful model system
for the study of cytokine release during megakaryocyte differentiation. 相似文献
140.
Rui Yan Mark Ottenbreit Bharati Hukku Michael Mally Sharong Chou Joseph Kaplan 《In vitro cellular & developmental biology. Animal》1996,32(10):656-662
Summary Methods for monitoring cell line identification and authentication include species-specific immunofluorescence, isoenzyme
phenotyping, chromosome analysis, and DNA fingerprinting. Most previous studies of DNA fingerprinting of cell lines have used
restriction fragment length polymorphism analysis. In this study, we examined the utility of an alternative and simpler method
of cell line DNA fingerprinting—polymerase chain reaction (PCR) amplification of fragment length polymorphisms. Fourteen human
cell lines previously found by other methods to be either related or disparate were subjected to DNA fingerprinting by PCR
amplification of selected fragment length polymorphism loci. Cell identification patterns by this method were concordant with
those obtained by isoenzyme phenotyping and restriction fragment length polymorphism-DNA fingerprinting, and were reproducible
within and between assays on different DNA extracts of the same cell line. High precision was achieved with electrophoretic
separation of amplified DNA products on high resolution agarose or polyacrylamide gels, and with fragment length polymorphism
(FLP) loci-specific “allelic ladders” to identify individual FLP alleles. Determination of the composite fingerprint of a
cell line at six appropriately chosen fragment length polymorphism loci should achieve a minimum discrimination power of 0.999.
The ability of PCR-based fragment length polymorphism DNA fingerprinting to precisely and accurately identify the alleles
of different human cell lines at multiple polymorphic fragment length polymorphism loci demonstrates the feasibility of developing
a cell line DNA fingerprint reference database as a powerful additional tool for future cell line identification and authentication. 相似文献