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51.
Mitsutoshi Kato Jie Yang Takaaki Iwai Akira Tanamura Toru Arino Osamu Kawashima Nobuakira Takeda 《Molecular and cellular biochemistry》1993,119(1-2):89-94
ADP/ATP carrier protein (AAC) is located in the mitochondrial inner membrane and has an important function in mitochondrial energy supply. This protein transports ATP to the cytoplasm and counter transports ADP into the mitochondria. J-2-N cardiomyopathic hamsters were investigated to determine the AAC content in cardiac mitochondria. After recording an electrocardiogram and collecting blood, the cardiac mitochondria were isolated. The mitochondrial membranes were labelled with eosin-5-maleimide (EMA) and separated on SDS polyacrylamide gels. The position of the AAC component was identified by exposing the gel under UV light, and the AAC content was determined by densitometry after staining with Coomassie blue. The AAC content ratio was significantly decreased in both 10-week-old and 1-year survived J-2-N hamsters when compared to control Golden hamster. Among 10-week-old J-2-N hamsters, the decrease in the AAC content ratio was more marked for the animals with more severe myocardial damage. The H+-ATPase activities of mitochondrial membrane were higher in 10-week-old J-2-N hamsters than in control hamsters. These results suggest that the decrease of AAC in J-2-N hamster plays an important role in the pathogenesis of cardiomyopathy in J-2-N hamsters. 相似文献
52.
Takahiro Okazaki Chiemi Nakanishi-Ito Naohiro Seo Takae Tanino Masafumi Takiguchi Kohji Egawa 《Cancer immunology, immunotherapy : CII》1993,36(2):83-88
Tumor-specific expression of Qa-2k antigen coded by the Q5k gene on various mouse tumor cells and immunological response of the host mice to the antigen have been demonstrated [Seo et al. (1992) J Exp Med 175: 547; Tanino et al. (1992) Cancer Immunol Immunother 35: 230]. The possibility was examined that Qa-2 antigen is one of the recognition target molecules of immunopotentiator-induced, H-2-nonrestricted tumoricidal lymphocytes of Qa-2– mice. Lymphocytes stimulated in vivo withP. acnes or culture-induced anomalous killers of B6.K1 mice did not exhibit significant in vitro cytotoxicity against B6.K1 lymphoblasts but lysed their Qa-2,3-congenic counterpart B6 lymphoblasts. To demonstrate the Qa-2 specificity of such cytotoxic cells more precisely, an L cell transformant clone (LQ7b/Kb), which expressed the 1 and 2 domains of the Qa-2 antigen (Q7b gene product), was generated by transfecting a cloned plasmid DNA containing a hybrid gene constructed from the 5 half of the Q7b gene and the 3 half of the H-2Kb gene (pQ7b/Kb). Using LQ7b/Kb cells as the target cells and the nylon-wool-nonadherent fraction of lymphocytes fromP. acnes-stimulated (C3H/He × B6.K1)F1 mice (H-2k, Qa-2–) as the effector cells of the in vitro cytotoxicity reaction, the presence of cytotoxic cells that recognize the 1/2 region of the Q7b gene product was demonstrated. The cytotoxic activity was dependent on T cells bearing T cell receptors of the / type (TCR/). The (C3H/He × B6.K1)F1 effector cells, as well as the B6.K1 effector cells also lysed BW5147 lymphoma cells (Qa-2k+) derived from AKR mice (Qa-2–, H-2k). By target-competition experiments it was shown that some of the effector cells lytic to BW5147 were identical to those that lysed LQ7b/Kb. Therefore some of the tumoricidal cells induced by the immunopotentiator interact with the target tumor cells through recognition of the 1/2 region of the Qa-2k tumor antigen by TCR/. 相似文献
53.
Tobacco plants were transformed with derivatives of a binary vector pMON505 and two kanamycin resistant lines that were nopaline positive were selected for second transformation. The plasmids used for the second transformation were derivatives of pMON850 which carries the nopaline synthase gene in addition to a gene for gentamicin resistance. Insertion of each transgene was confirmed by Southern hybridization. Surprisingly, we found that more than 50% of the doubly transformed tobacco plants were nopaline negative. Tobacco plants that were transformed only by the second vector exhibited nopaline accumulation. DNA methylation patterns at the HpaII site in the promoter region of the nopaline synthase gene did not correlate with the nopaline phenotype. In some plant lines, seedlings of the R1 generation which segregated out the second T-DNA insertion recovered the nop+ phenotype. These results indicate that nopaline accumulation was inhibited by the presence of the second T-DNA.Abbreviations T-DNA
transferred DNA
- NPTII
neomycin phosphotransferase II
-
uidA
-glucuronidase
- Km
kanamycin
- Gm
gentamicin
- nop+
nopaline positive
- nop–
nopaline negative
- MS
medium, Murashige-Skoog medium 相似文献
54.
Toru Terachi 《Journal of plant research》1993,106(1):75-79
Recent advances in manipulating nucleic acids have opened a new research field called plant molecular systematics. This short
review provides an overview of molecular techniques which have been used in the analysis of DNA molecules for the study of
plant systematics, with a special emphasis on PCR. The early application of DNA analysis, DNA/DNA hybridization, has not become
popular with plant systematists, because of several disadvantages inherent in the method. The survey of restriction fragment
length polymorphisms (RFLPs), on the contrary, has become one of the preferred methods used by plant molecular systematists,
since the method is relatively easy to perform. Although unambiguous data can be obtained by both long-range restriction mapping
and nucleotide sequencing, these approaches may have limited use in plant molecular systematics because of their laborious
experimental procedures relying on conventional molecular cloning techniques. To date, PCR based analyses of the DNA molecule
seem to be the most suitable experimental approach for plant molecular systematics. Several advantages of the method have
changed both the quality and quantity of the DNA data. Further application of PCR to plant molecular systematics will open
up a new era in the field.
The present paper is based on the contribution which was read in a symposium entitled “Organellar DNA Variations in Higher
Plants and their Taxonomic Significance”, at the 50th Annual Meeting of the Botanical Society of Japan in Shizuoka on October
2, 1990, under the auspices of the Japan Society of Plant Taxonomists. 相似文献
55.
Summary A new process for the production of small size dextran is developed in which dextran is produced by cultures of Leuconostoc mesenteroides in the presence of a partially constitutive mutant of Lipomyces starkeyi producing dextranase. Mixed cultures were examined by scanning electron microscopy with ruthenium to show the effects of the mixed culture on low molecular weight dextran (M.W. of 5,000 – 100,000) formation. The presence of the size variation in dextran was confirmed by gel permeation chromatography. 相似文献
56.
57.
58.
An assay for ferredoxin-glutamate synthase is introduced thatuses an anion exchange resin to isolate the glutamate formedand subsequent determination with the ninhydrin procedure. Theenzyme was purified 200-fold from corn leaves by ammonium sulfatefractionation and chromatography on DEAE-cellulose, DEAE-Sephaceland ferredoxin- Sepharose. The purified enzyme had a specificactivity of 14 µmoles glutamate formed min1mg1protein. The enzyme has a molecular weight of 160,000. The pHoptimum for catalytic activity is 6.9. The isoelectric pointis at pH 4.2. The apparent Km values of the enzyme for L-glutamine,2-oxoglutarate and ferredoxin are 1,100, 240 and 1.7 µM.The enzyme has a high specificity toward these substrates witha stoichiometry between glutamate formation and glutamine consumption.Sulfhydryl reagents, bathophenanthroline, phthalein acids andazaserine produced strong inhibition of the enzyme activity.
1Permanent address: Department of Agricultural Chemistry, KyotoUniversity, Kyoto 606, Japan.
2To whom inquiries should be addressed. (Received July 7, 1979; ) 相似文献
59.
M C Steward Y Seo M Murakami H Watari 《Proceedings. Biological sciences / The Royal Society》1991,243(1307):115-120
Rubidium is a good substitute for potassium in many biological systems, and it has been suggested that rubidium-87 nuclear magnetic resonance (87Rb-NMR) spectroscopy could be used to measure K+ fluxes across membranes in intact tissues. To evaluate this possibility, isolated rat mandibular salivary glands were perfused with solutions containing Rb+ in place of K+. The 87Rb signals arising from the intra- and extracellular compartments were first separated by spectral subtraction and then subjected to line-shape analysis. The narrow extracellular signal was a single Lorentzian (line-width 156 Hz), whereas the broader intracellular signal consisted of two Lorentzian components (ca. 530 and 3080 Hz). Double-quantum filtering of the 87Rb signal from the glands revealed two components of transverse relaxation in antiphase (rate constants 1.8 and 13.3 ms-1), showing the probable involvement of quadrupolar interactions in the relaxation of intracellular Rb+. We conclude, therefore, that both line-shape analysis and double-quantum filtering could provide a basis for the measurement of unidirectional K+ fluxes in intact tissues. 相似文献
60.
Source of prolactin in human follicular fluid. 总被引:2,自引:0,他引:2
M Ohwaki N Suganuma H Seo A Nawa F Kikkawa O Narita N Matsui Y Tomoda 《Endocrinologia japonica》1992,39(6):601-607
To analyze whether prolactin (PRL) in human follicular fluid (FF) is synthesized locally or derived from the circulation, PRL concentrations of plasma and FF were determined in the patients after ovarian stimulations. The amounts of PRL messenger ribonucleic acid (mRNA) in the follicular tissues during different menstrual phases were also determined. The FF PRL concentration was correlated positively with plasma PRL and highest estradiol levels during the stimulatory cycle. No PRL mRNA sequence was detected in the RNAs extracted from follicles at any stage in the menstrual cycle, although beta-actin mRNA was detected in all samples. In a comparison with pituitary RNA, the PRL mRNA concentration in ovarian follicular tissues seemed to be 10,000 times less than that in the pituitary. These results suggest that FF PRL may not be synthesized locally, but derived from the pituitary via the circulation through passive diffusion, and thus regulated by estrogen. 相似文献