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51.
The effects of a synthetic growth promoter, 4-ethoxy-l-( p -tolyl)-S-triazine-2,6 (1H, 3H)-dione [TA], on growth and gravireaction of Zea mays L. (cv. LG 11) roots were investigated. In horizontal, intact roots, pretreatment with TA at 4 × 10−4 M inhibited the gravireaction. If the pretreated roots were rinsed with a buffer solution before incubation, the TA effect was reduced, indicating that a continuous presence of TA was necessary for its maximal activity. On the other hand, the TA pretreatment (1×10−5 , 1×10−4 and 4 × 10−4 M ) promoted the elongation of these roots. The TA effect was stronger for illuminated roots than for those kept in darkness. TA also decreased the lateral curvature of half-decapitated roots maintained vertically in light. This indicates that the action of TA could be associated with some growth inhibiting substances produced or released in cap cells. 相似文献
52.
Continuous cell cultures were established from imaginal wing discs of 2 Lepidoptera, Spodoptera frugiperda and Plodia interpunctella. The S. frugiperda line (IAL-SFD1) grows as multicellular vesicles and responds morphologically and biochemically to the insect hormone, 20-hydroxyecdysone. In contrast, the P. interpunctella cells (IAL-PID2) grow as attached monolayers of small spindle-shaped cells and do not appear to have specific responses to 20-hydroxyecdysone, although growth rates are slowed in these cells upon exposure to the hormone. 相似文献
53.
^60Co—γ射线诱导的小麦T型雄性不育系育性恢复突变 总被引:5,自引:1,他引:4
用~(60)Co-γ射线诱导小麦T型雄性不育系T小偃4号A、T郑引1号A均获得了农艺性状优良、恢复力强的恢复系。育性恢复突变是涉及一个或少数几个位点核基因的显性突变。利用性状优良的T型不育系诱导育性恢复突变是选育恢复系和发掘恢复源的有效途径。 相似文献
54.
玉米自交系间遗传距离与产量杂种优势,杂种产量的关系 总被引:24,自引:0,他引:24
以13个玉米自交系及其按双列杂交配制的78个单交种为材料,研究性状选择、亲本选择对遗传距离与产量杂种优势、杂种产量关系的影响,结果表明:(1)当性状数较少时,遗传距离与产量杂种优势、杂种产量的关系因性状的不同而异;当性状数较多时,遗传距离与产量杂种优势、杂种产量的关系为抛物线,受性状影响较小;(2)当所选亲本材料的遗传差异较大时,遗传距离与产量杂种优势的关系为抛物线;当所选亲本材料的遗传差异较小时,遗传距离与产量杂种优势的关系为直线或不相关。 相似文献
55.
玉米花粉单倍体植株染色体上异染色质的变异 总被引:4,自引:1,他引:3
我们用Giemsa BSG C-带技术检查了玉米花药培养获得的花粉单倍体植株根尖细胞染色体上异染色质的变异,观察结果表明,有的植株所显示的C-带数目是与供体植株的相一致,有的植株所显示的C-带数目则发生了显著变化,其中有的增加,有的减少。并讨论了异染色质发生变异的可能原因。还相应地观察到间期核中染色中心的变化是与中期染色体上C-带数目的变化相一致。 相似文献
56.
Study of the in vitro bioactivation of albendazole in human liver microsomes and hepatoma cell lines
Sylvie Rolin Hajar Souhaili-El Amri Anne-Marie Batt Michele Levy Denyse Bagrel Gerard Siest 《Cell biology and toxicology》1989,5(1):1-14
The metabolism of albendazole (ABZ), a benzimidazole anthelminthic, was studied in either microsomal preparations of human liver biopsies or cultured human hepatoma cell lines. Metabolites were analyzed by HPLC. Our data show that microsomes from human biopsies and two human cell lines, HepG2 and Hep3B, oxidize the drug to the sulfoxide very efficiently, whereas the third cell line tested, SK-HEP-1, does not. Both cytochrome P-450 dependent monooxygenases and favin-containing monooxygenases appear to be involved in human ABZ metabolism. Using the cell line displaying the highest ABZ-metabolizing activity, HepG2, the cytotoxic and the inducing effects of the parent drug ABZ and of two primary metabolites, the sulfoxide and the sulfone were studied. These three chemicals provoked a rise in mitotic index resulting from cell division blockage at the prophase or at the metaphase (ABZ metabolites) stage, and ABZ was more cytotoxic than its metabolites. With regard to enzyme-inducing effects, our data clearly demonstrate that the sulfoxide and, to a lesser degree, the sulfone are potent inducers of some drug metabolizing enzymes (i.e., cytochrome P-488 dependent monooxygenases and UDP glucuronyltransferase), whereas ABZ fails to increase and even slightly decreases these enzymatic activities. In conclusion, the HepG2 human hepatoma cell line appears to be suitable for the study of many parameters of metabolism and action of ABZ and other structurally related compounds in humans.Abbreviations ABZ
albendazole
- B[a]P
benzo[a]pyrene
- HPLC
high-performance liquid chromatography
- MC
3-methylcholanthrene
- MFO
mixed-function oxidase
- UDPGT
UDP-glucuronyltransferase 相似文献
57.
58.
Hiroaki Kataoka Kazuki Nabeshima Naoto Komada Masashi Koono 《Virchows Archiv. B, Cell pathology including molecular pathology》1989,57(1):157-165
Two new human cell lines, RCM-1 and CoCM-1, have been established from primary colorectal adenocarcinomas. Both cell lines
were unique in that the cultures secreted trypsin inhibitors in vitro. The activities of these inhibitors were accumulated
in serum-free media of both cell lines over a period of several days. Two inhibitors (PI-1 and PI-2) were isolated from serum-free
conditioned medium in which RCM-1 was grown by anion-exchange and gel filtration high-performance liquid chromatography. PI-1
inhibited trypsin and chymotrypsin strongly, and pancreatic elastase weakly. Its molecular weight was about 57 kilodaltons
(Kd) as determined by gel filtration chromatography. It cross-reacted with the antiserum elicited against human α1-antitrypsin in double immunodiffusion. PI-1 corresponding to α1
- antitrypsin was also demonstrated immunohistochemically in both cell lines. PI-2 inhibited trypsin strongly, and chymotrypsin,
kallikrein and plasmin weakly. It had higher molecular weight (200–300 Kd) than that of PI-1, and did not crossreact with
antisera against human α1-antitrypsin, α2-macroglobulin, α1-antichymotrypsin, α2-plasmin inhibitor, inter-α-trypsin inhibitor and urinary trypsin inhibitor. RCM-1 and CoCM-1 are the first colorectal adenocarcinoma
cell lines that secrete functionally active trypsin inhibitors, including α1-antitrypsin in vitro, and are useful for the study of tumor-cell derived proteinase inhibitors. 相似文献
59.
60.