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51.
Frederick J. Darfler 《In vitro cellular & developmental biology. Plant》1990,26(8):769-778
Summary A protein-free medium, termed ABC, has been developed which essentially eliminates the need for serum proteins. ABC supports
the long-term growth of murine hybridomas as well as other transformed cells of the immune system. The requirement of hybridoma
growth for transferrin has been met by substituting the soluble organo-iron compound, sodium nitroprusside. Substantial improvement
in the growth of hybridomas was afforded by the inclusion of 18 trace elements complexed to disodium ethylene diaminetetraacetate
(EDTA). The medium was further improved by the inclusion of components not found in Ham's F12 medium or by raising the concentrations
of existing low molecular weight components. Murine hybridomas can be cultured routinely in this protein-free medium in an
anchorage-independent manner with doubling times generally under 24 h. Visualized on electrophoretic gels, levels of monoclonal
antibody taken from those cultures often exceeded 80% of the total protein. The medium was also able to support the growth
of HuT 78 and H9 cells as well as certain other transformed cells of the immune system. In addition, normal human peripheral
blood lymphocytes, activated with phytohemagglutinin and cultured with 50 U/ml recombinant interleukin 2, could be grown for
2 wk with a 50-fold expansion over input cell number. 相似文献
52.
Mitsuo Satoh Shinji Hosoi Seiji Sato 《In vitro cellular & developmental biology. Plant》1990,26(11):1101-1104
Summary The protease activity in serum-free conditioned medium of chinese hamster ovary (CHO) cells was measured using peptidyl (or
aminoacyl)-4-methylcoumaryl-7-amides (MCAs) as the substrates. Aminopeptidase increased in level as amounts of nonviable cells
increased during cultivation in serum-free medium, indicating that the activity seems to be originated from intracellular
proteases. The activity toward Boc-Leu-Arg-Arg-MCA, which was strongly inhibited by p-chloromercuribenzonate and N-ethylmaleimide,
was the strongest among those toward peptidyl-MCAs in the conditioned medium within 48 h-cultivation in serum-free medium.
In contrast to the case of aminopeptidase activity, the endopeptidase activity decreased in level after 48 h-cultivation although
amounts of nonviable cells increases. Thus, CHO cells continuously secrete the cysteine proteases.
This work was supported by the management of the Research Association for Biotechnology as a part of the R&D of Basic Technology
for Future Industries sponsored by NEDO (New Energy and Industrial Technology Development Organization). 相似文献
53.
Koichi Rikimaru Hitomi Toda Noriko Tachikawa Nobuyuki Kamata Shoji Enomoto 《In vitro cellular & developmental biology. Plant》1990,26(9):849-856
Summary A novel protein-free synthetic medium has been developed for the culture of human squamous cell carcinoma cells. This medium,
designated PF86-1, supports the serial subcultivation of six out of nine human squamous cell carcinoma cell lines in a protein-free,
chemically defined condition without the adapting culture from serum-containing conditions. These cell lines growing in PF86-1
exhibited nearly equal potency to grow in massive culture without noticeable changes in morphology but presented a significantly
decreased level of colony forming efficiency when compared with the cells cultured in serum-containing media, suggesting the
implication of some autocrine mechanism. Interestingly, this medium supported the growth of normal human squamous cells of
oral mucosa and skin for more than 2 mo. in the primary explant culture in spite of high levels of calcium ion concentration,
where the overgrowth of fibroblasts as contaminant was not observed. These results suggest that PF86-1 supports the growth
of cells derived from epidermal tissues selectively and provides the same defined condition for growth of malignant and nonmalignant
human squamous cells. It seems, therefore, that PF86-1 allows investigations on the products of squamous cell carcinoma cells
or on the differences of growth mechanisms between normal and neoplastic human squamous cells. 相似文献
54.
In vitro development of one-cell embryos from outbred mice: Influence of culture medium composition 总被引:2,自引:0,他引:2
Akiko Spindle 《In vitro cellular & developmental biology. Plant》1990,26(2):151-156
Summary One-cell embryos from outbred mice (CF1, CD-1, and Dub:ICR) were cultured in various modifications of egg culture medium (ECM).
The best development was observed in medium in which inorganic salts of modified T6 medium (mT6) replaced those of ECM. In
this modification (TE), 66% of one-cell CF1 embryos developed into blastocysts, comared to 46 and 43% for ECM and mT6, respectively.
Moreover, the cell numbers of blastocysts developing in TE (74.9±3.3) were higher than the cell numbers of those developing
in ECM (55.1±2.4). The culture requirements of embryos varied between different stocks of mice: Fewer CF1 embryos developed
to the blastocyst stage than either Dub:ICR embryos (90%) or CD-1 embryos (84%). Lowering the osmolarity of the medium from
300 to 280 mOsm, increasing the concentration of KC1 from 1.42 to 25 mM, or omitting lactate from the medium during Day 1 of culture did not further improve development of embryos, in contrast
to previous reports. However, the time at which embryos were transferred to outgrowth medium influenced their postblastocyst
development. The best development was observed when embryos were transferred on Day 4 of culture at the late morula-early
blastocyst stage.
This work was supported by the Office of Health and Environmental Research, U.S. Department of Energy, Washington, DC, contract
DE-AC03-76-SF01012. 相似文献
55.
56.
An in vitro procedure for large scale multiplication of Sterculia urens Roxb. (Gum Kadaya Tree) has been developed using cotyledonary node segments. An average of 4.0 shoots per node were obtained on Murashige and Skoog's (MS) medium containing 2.0 mgl–1 6-benzyl amino-purine (BAP) within 21 days of initial culture. Upon subsequent subculture 16 shoots/node could be harvested every three weeks and upto three times. Sixty per cent of the shoots were successfully rooted. Rooted plantlets were transferred to plastic pots containing soil under mist house conditions before they were finally exposed to an external environment. Fifty seven per cent of the plantlets survived in nursery sheds. 相似文献
57.
In vitro multiplication in liquid culture of Syngonium contaminated with Bacillus spp. and Rathayibacter tritici 总被引:5,自引:0,他引:5
Contaminated Syngonium clusters were multiplied in an air lift bioreactor in liquid medium containing sucrose with the medium being circulated through a sterilizing filter. After 30 days, the culture in filtered medium produced 19.5 shoot initials per gram fresh weight of inoculum compared to 8.7 shoot initials produced in unfiltered medium. Transfer to an elongation medium with 30 mg l-1 Rifampicin produced shoots on 67% of the clusters, while transfer to elongation medium without Rifampicin poduced shoots on 40% of the clusters. Clusters grown for three subcultures in a reactor without medium filtration had lost their multiplication ability. Clusters grown for three subcultures in a reactor with filtration, however, continued to show a two-three fold increase in fresh weight and shoot production.Abbreviations MS
Murashige and Skoog 相似文献
58.
Organogenic callus cultures of Solanum paludosum were obtained from root, hypocotyle and cotyledon explants of plantlets cultured in sterile conditions. These callus cultures developed multiple shoots which proliferated in Murashige and Skoog basal liquid medium. These multiple shoots produced solamargine, the main steroidal glycoalkaloid present in the unripe fruits.The optimization of the macronutrient composition of the liquid medium was performed by a method derived from the plant composition. This approach results in the establishment of an appropriate medium (SPOM medium) suitable for the improvement of both growth and solamargine production by multiple shoot cultures of S. paludosum. 相似文献
59.
FRANS J M BONNIER RITSERT C JANSEN JAAP M VAN TUYL 《The Annals of applied biology》1996,129(1):161-169
Collections of lily genotypes are usually maintained by yearly planting, harvesting and storage of the bulbs. To facilitate this maintenance, a storage method has been developed for a collection of lily genotypes, including Asiatic hybrids, Oriental hybrids, Lilium longiflorum and L. henryi. Scale bulblets were stored either dry, sealed air-tight in polyethylene bags, or in moist vermiculite in open polyethylene bags for a period of 2 yr. The decrease in mass, sprouting proportion and ion leakage or sprouting proportion alone were determined for treatments carried out at -2°C, °C and 17°C. Sealing scale bulblets in polyethylene bags at -2°C resulted in the smallest decrease in mass, the least ion leakage and the highest sprouting proportion after 2 yr of storage. 相似文献
60.
We designed an Integrated Media Preparation System (IMPS) for continuous, on-line preparation of cell culture media and delivery to intermediate storage vessels or directly to a bioreactor. Key components of the IMPS include: a high precision, continuous fluid mixing device; formulation-specific liquid medium concentrates; validated process controls and membrane filtration; and automated dispensing into large volume flexible plastic containers. The IMPS system is designed to produce sterile, single-strength liquid medium from common raw materials at a delivery rate of 1000–3000 liters per hour and will manufacture homogenous batches from several thousand liters to over 60,000 liters. Fortified nutrient media prepared from multi-component 50X concentrates have been demonstrated to accelerate bioreactor seed chains, increase product yield, and reduce the overall manufacturing cost of nutrient medium. A productivity matrix will analyze the fully-loaded costs and contrast alternative methods for media preparation against projected biological yield.Abbreviations IMPS
Integrated Media Preparation System
- 50X
Nutrient fluid components formulated at fifty-fold final use concentration
- 1X
Nutrient fluid formulated at final, single-strength use concentration
- cGMP
Current Good Manufacturing Practices
- SCADA
Supervisory Control and Data Acquisition
- PLC
Process Logic Controller
- LTI
Life Technologies, Inc.
- WFI
Water for Injection
- CIP
Clean in place
- SIP
Sterilize in place
- HPLC
High performance liquid chromatography
- DMEM
Dulbecco's Modified Eagle's Medium 相似文献