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1.
2.
Orosomucoid (ORM) typing by isoelectric focusing: evidence for gene duplication of ORM1 and genetic polymorphism of ORM2 总被引:2,自引:0,他引:2
Summary It has been demonstrated that the genetic polymorphism of human serum orosomucoid (ORM) is controlled by polymorphic ORM1
and monomorphic ORM2 loci. In this study a Japanese family was encountered in which several members had puzzling electrophoretic
patterns consisting of four bands. The ORM patterns were due to the products of a duplicated ORM1 locus haplotype (ORM1
*
2·1) or the products of new variant alleles at the ORM2 locus. The ORM1
*
2·1 haplotype is very common in the Japanese population, occurring at an allele frequency of 0.16. The increased occurrence of
ORM1 2-1 and the heterogeneity in band intensity among ORM1 2-1 phenotypes could be explained in terms of a duplicated gene
ORM1
*
2·1. The ORM2 locus proved to be polymorphic, with six alleles in the Japanese population.
Dedicated to Professor Dr. K. Nishigami on the occasion of his 60th birthday 相似文献
3.
Hiroshi Yonemitsu Koichiro Shimomura Motoyoshi Satake Shunji Mochida Masahiko Tanaka Thoru Endo Akira Kaji 《Plant cell reports》1990,9(6):307-310
Hairy roots were obtained following inoculation of the stems of Lobelia inflata L. with Agrobacterium rhizogenes strain ATCC 15834. These hairy roots contained agropine and mannopine. In addition, lobeline was detected by HPLC and confirmed by mass spectrometry. Various media were tested for the growth of hairy roots as well as for the content of lobeline in hairy roots. The growth rate of hairy roots cultured in Nitsch and Nitsch's medium was approximately one third of those cultured in other media. The lobeline content of hairy roots (18–54 g/g dry weight) cultured in these media was the same order of magnitude compared with that of roots of L. inflata (24 g/g dry weight) cultivated in pots. The hairy roots cultured in Nitsch and Nitsch's medium were morphologically different from those cultured in other media.Abbreviations MS medium
Murashige and Skoog's medium
- 1/2 MS medium
one-half strength of the standard Murashige and Skoog's medium
- B5 medium
Gamborg's B5 medium
- NN medium
Nitsch and Nitsch's medium
- FW
fresh weight
- DW
dry weight 相似文献
4.
Masahiko Makino Wendy F. Davidson Torgny N. Fredrickson Janet W. Hartley Herbert C. Morse III 《Immunogenetics》1991,33(5-6):345-351
Mice of certain strains are highly sensitive to development of a severe immunodeficiency disease following inoculation as adults with LP-BM5 murine leukemia viruses (MuLV) whereas others are extremely resistant. These strain-dependent differences in response to infection have been shown to be genetically determined with resistance to disease being, in general, associated with homozygosity for Fv-1
nand H-2 haplotypes a and d and sensitivity with homozygosity for Fv-1
band other H-2 haplotypes including b, s, and q. The Fv-1
b, H-2
rstrain RIIIS/J (RIIIS) was found to be highly resistant to disease even though B10.RIII(71NS)/J (B10.RIII), also H-2
r, was very sensitive, thus excluding a role for H-2 in the resistance of RIIIS. The characteristics of RIIIS resistance were evaluated in studies of infected (B10.RIII×RIIIS) F1, F2 and reciprocal backcross mice. Resistance to disease was shown to be semidominant and determined by more than one gene, although a preponderant influence of a single gene was suggested. Studies of segregating populations showed that resistance was not associated with or linked to polymorphisms of the V
\complex or genes in proximity to the Emv-2 locus on chromosome 8. However, there was almost complete concordance between absence of disease in infected mice and inhibition of ecotropic virus spread. These results demonstrate that genes other than Fv-1 or H-2 can profoundly influence the development of retrovirus-induced immunodeficiency and replication of ecotropic viruses.Abbreviations MuLV
murine leukemia virus
- MCF
mink cell focus-inducing MuLV
- B6
C57BL/6
- BM5d
the defective virus in LP-BM5 MuLV
- MAIDS
murine acquired immunodeficiency syndrome
- RIIIS
RIIIS/J
- B10.RIII
B10.RIII (71NS)/J
- MLR
mixed lymphocyte reaction
- FACS
fluorescence activated cell sorter 相似文献
5.
Masaki Sugiura Tsutomu Takagi Masahiko Kisumi 《Applied microbiology and biotechnology》1985,21(3-4):213-219
Summary Proline-producing strains of Serratia marcescens Sr41 were constructed by three rounds of mutagenesis. A strain SP103 which did not degrade l-proline carried the putA mutation leading to lack of proline oxidase. A 3,4-dehydroproline-resistant mutant SP105, derived from strain SP103, carried the dpr-1 mutation which resulted in desensitization of the feedback inhibition of glutamate kinase. Strain SP103 produced 5.5 mg of l-proline per ml of fermentation medium containing sucrose and urea. Growth inhibition by proline analogs was enhanced when succinate was used as a carbon source in the medium. A thiazolidine-4-carboxylate-resistant mutant SP126 derived from strain SP105 produced 20.5 mg of l-proline per ml of medium. The mutation carried by strain SP126 might be distant from dpr-1 and putA mutations on the chromosome. Pyrroline-5-carboxylate reductase was not repressed by proline in S. marcescens Sr41. 相似文献
6.
A population of a viperid snake,Trimeresurus flavoviridis, was studied over 10 years by removal trapping on a small subtropical island in Japan. The sex ratio of trapped individuals changed seasonally, but was not biased to either sex in the whole sample of 258 individuals. The age of each individual was estimated through the size structure and the age-size relationship. The minimum number of individuals at the beginning of the study was estimated through accumulating older individuals trapped in the subsequent years. By assuming an annual natural survival rate in the course of this accumulation, an age structure was simulated which led to calculate a resulted natural survival rate. The assumed rate of 0.62 fitted best to the resulted one. The annual trapped proportion estimated on the simulated absolute number of individuals was higher in older individuals than in younger ones with the overall mean of 16%. 相似文献
7.
8.
9.
Presomite stage rat embryos were cultured for 45–49 hr with medium containing various adrenergic agonists and antagonists.
-Norepinephrine but not
-norepinephrine (several orders of magnitude less potent than the
-isomer at α-1 adrenergic receptors) resulted in a dose-dependent increase of situs inversus similar to that found for phenylephrine, an α-1 adrenergic agonist. Prazosin, an α-1 adrenergic antagonist, inhibited phenylephrine-induced situs inversus in a dose-dependent manner. Neither dexmedetomidine, an α-2 adrenergic agonist, nor isoproterenol, a β adrenergic agonist, caused situs inversus. These results provide pharmacological evidence that stimulation of α-1 but not of α-2 and β adrenergic receptors modulates the control of left/right sidedness in rat embryos. 相似文献
10.
Saito Masahiko; Kondo Noriaki; Yamaguchi Hisao; Hashimoto Tohru 《Plant & cell physiology》1976,17(3):411-416
Nine bibenzyls and 10 stilbenes were synthesized as analoguesof batatasin III, a growth inhibitor isolated from dormant yambulbils, and examined for their plant growth-regulating activities.The bioassays used were the elongation of dark-grown intactrice coleoptiles, auxin-induced elongation of excised oat coleoptiles,and germination of rape and barnyard grass seeds. In the elongationof intact rice coleoptiles, 3,3'-dihydroxy-5-methoxy- (batatasinIII), 3,5-dimethoxy-3'-nitro-, 4'-bromo-3-nitro-, 3-amino-3'-chloro-,3-amino-4'-chloro-bibenzyls and 3-benzyloxy-4'-bromo-5-methoxy-,3-benzyloxy-3',4'-dichloro-5-methoxy-stilbenes were inhibitory,and 4'-bromo-3-nitrostilbene was promotive at a concentrationof 100 mg/liter. The results obtained by the other bioassayswere qualitatively consistent with these findings, although3-amino-4'- chlorobibenzyl and 4'-bromo-3-nitrostilbene werenot tested in all the bioassays. In the seed germination, which was rather tolerant to the testanalogues, batatasin III was inactive but 3-benzyloxy-4'-bromo-5-methoxy-and 3-benzyloxy-3',4'-dichloro- 5-methoxystilbenes were veryactive. Thus, if substituted properly, bibenzyls and stilbenes are activewithout hydroxyl and methoxyl group(s) as the functional group.
3 Present address: The National Institute for EnvironmentalStudies, Yatabc, Ibaraki 300-21, Japan. (Received November 19, 1975; ) 相似文献