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141.
Nobuko Mutoh Makoto Kimura Yasuyuki Oshima Hideo Iwaki 《Journal of plant research》1985,98(2):159-170
In an old field grassland dominated byMiscanthus sinensis Anderss. the community structures, phytomass, dominance ofM. sinensis and species diversity were measured. Species and life form composition of the stand were characterized by higher percentages
of therophytes, woody and shrubby species, liana and alien species.
From May so September in 1982, all the aboveground parts were harvested from each of the four quadrats (2 m×2 m) once a month.
Seasonal peak of aboveground phytomass, in September, was 1027 g d.w.m−2 to whichM. sinensis contributed as much as 96.5%. With the progress of the growing season,M. sinensis became increasingly important both in stand phytomass and in dominance, whereas species diversity based on the dry weight
contributions of constituent species decreased. Our analysis of these seasonal trends showed that the diversity was largely
a function of dominance of the most important species, rather than that of stand phytomass or productivity. The simultaneous
measurements of 20 quadrats in late August 1983, also supported the above conclusion. 相似文献
142.
143.
Akio Nakane Shinsuke Nishikawa Sanae Sasaki Tomisato Miura Misako Asano Masashi Kohanawa Tomonori Minagawa 《FEMS immunology and medical microbiology》1995,11(4):321-327
Abstract In vivo induction of cytokines by a monoclonal antibody (mAb) against T-cell receptor (TCR) αβ and the protective effect induced by the mAb on a lethal infection with Listeria monocytogenes were studied. Injection of anti-TCR αβ mAb induced rapid production of endogenous tumour necrosis factor in the spleens, and gamma interferon and interleukin-6 in the bloodstreams and spleens of mice. Administration of anti-CD4 mAb, anti-CD8 mAb, or anti-Thy1.2 mAb resulted in suppression of anti-TCR αβ mAb-induced endogenous cytokine production. Mice were protected against lethal L. monocytogenes infection when treated with anti-TCR αβ mAb. The protective effect was not demonstrated in CD4 + cell- or CD8 + cell-depleted mice. These results suggest that anti-TCR αβ mAb shows a protective effect on a lethal infection with L. monocytogenes in mice and that the mAb-induced endogenous cytokines might be involved in the effect of anti-TCR αβ mAb. 相似文献
144.
Nobuko Mori Masaaki Okumoto Martin A. van Der Valk Syunsuke Imai Satomi Haga Kozaburo Esaki Augustinus A. M. Hart Peter Demant 《Genomics》1995,25(3)
Genetic dissection of susceptibility to radiation-induced apoptosis of thymocytes was performed by counting dead cells in histologically processed thymuses after 0.5 Gy of whole-body X-irradiation, using recombinant congenic (CcS/Dem) strains derived from inbred mouse strains BALB/cHeA (susceptible) and STS/A (resistant). A high (8/20) number of strains with lower dead cell scores than BALB/cHeA among CcS/ Dem recombinant congenic strains (RCS), which contain 12.5% of STS/A genome in the genetic background of BALB/cHeA strain, indicates that the difference between BALB/cHeA and STS/A is caused by several genes and that susceptibility probably requires BALB/ cHeA alleles at more than one locus. Similar results were obtained with CXS/Hg recombinant inbred (CXS/ Hg) strains. Analysis of F2 hybrids between BALB/ cHeA and CcS-7, one of the CcS/Dem strains that showed lower dead cell scores than BALB/cHeA, demonstrated that a novel gene (Rapop1, radiation-induced apoptosis 1) controlling susceptibility to radiation-induced apoptosis in the thymus is located in the proximal region of mouse chromosome 16. 相似文献
145.
Nobuko Matsumoto Takeshi Nakamura Yoshie Yasui Junzo Torii 《Biotechnic & histochemistry》1997,72(4):191-197
The cDNA sequence of troponin I (TnI), one of the subunits of the skeletal muscle regulatory protein, differs between slow-twitch muscle and fast-twitch muscle. We prepared monoclonal antibodies td the slow and fast isoforms of human TnI for the purpose of differentiating muscle fiber types in human neuromuscular disorders. Slow TnI antibody was labeled with tetramethylrhodamine isothiocyanate while fast TnI antibody was labeled with fluorescein isothiocyanate; then these two antibodies were mixed. This mixture was then used to stain biopsied muscle from patients with neuromuscular disorders. It was possible to differentiate muscle fibers into slow, fast and intermediate fibers having various contents of slow and fast TnI. In tissue composed of small muscle fibers, this method facilitated differentiation of types of muscle fibers by allowing staining of only a single section. The usefulness of our technique using slow and fast TnI antibodies is discussed in comparison with ATPase staining. Because our staining method can distinguish slow and fast fiber components, it is useful for clinical application. 相似文献
146.
Junko Adachi Kuniaki Watanabe Kiichi Fukui Nobuko Ohmido Keiko Kosuge 《Journal of plant research》1997,110(3):371-377
The chromosomal locations of the 45S (18S-5.8S-26S) and 5S ribosomal DNA in theBrachyscome lineariloba complex and two related species have been determined by the use of multicolor fluorescencein situ hybridization (McFISH). TheBrachyscome lineariloba complex includes five cytodemes with 2n=4, 8, 10, 12 and 16. Each of the 5S and 45S rDNA loci occurs at two sites on chromosomes in cytodemes with 2n=4. While in cytodemes with 2n=8, 10, 12 and 16, the number of 5S rDNA sites increases from four to eight paralleled to the genomic addition of diploid
(4 chromosomes) or haploid (2 chromosomes) dosage. Of the 5S rDNA sites, only one pair is major, except for the cytodeme with
2n=10. The remaining 5S rDNA sites are minor and seem to have reduced the unit number of the 5S rDNA during the successive genomic
additions. The 45S rDNA site is detected only at two nucleolar organizing regions in all cytodemes regardless of successive
genomic addition. The loss or diminution of 45S rDNA sequences seem to have proceeded more rapidly than 5S rDNA sequences
in theB. lineariloba complex. 相似文献
147.
148.
Aiko Yamazaki Masateru Yashiro Sumiyuki Mii Ryoichi Aki Yuko Hamada Nobuko Arakawa 《Cell cycle (Georgetown, Tex.)》2016,15(5):760-765
Nestin-expressing hair-follicle-associated pluripotent (HAP) stem cells are located in the bulge area of the follicle. Previous studies have shown that HAP stem cells can differentiate to neurons, glia, keratinocytes, smooth muscle cells, and melanocytes in vitro. HAP stem cells effected nerve and spinal cord regeneration in mouse models. Recently, we demonstrated that HAP stem cells differentiated to beating cardiac muscle cells. The differentiation potential to cardiac muscle cells was greatest in the upper part of the follicle. The beat rate of the cardiac muscle cells was stimulated by isoproterenol. In the present study, we observed that isoproterenol directs HAP stem cells to differentiate to cardiac muscle cells in large numbers in culture compared to HAP stem cells not supplemented with isoproterenol. The addition of activin A, bone morphogenetic protein 4, and basic fibroblast growth factor, along with isoproternal, induced the cardiac muscle cells to form tissue sheets of beating heart muscle cells. These results demonstrate that HAP stem cells have great potential to form beating cardiac muscle cells in tissue sheets. 相似文献
149.
Aiko Yamazaki Yuko Hamada Nobuko Arakawa Masateru Yashiro Sumiyuki Mii Ryoichi Aki 《Cell cycle (Georgetown, Tex.)》2016,15(19):2619-2625
We have previously discovered nestin-expressing hair-follicle-associated pluripotent (HAP) stem cells and have shown that they can differentiate to neurons, glia, and many other cell types. HAP stem cells can be used for nerve and spinal cord repair. We have recently shown the HAP stem cells can differentiate to beating heart-muscle cells and tissue sheets of beating heart-muscle cells. In the present study, we determined the efficiency of HAP stem cells from mouse vibrissa hair follicles of various ages to differentiate to beating heart-muscle cells. We observed that the whiskers located near the ear were more efficient to differentiate to cardiac-muscle cells compared to whiskers located near the nose. Differentiation to cardiac-muscle cells from HAP stem cells in cultured whiskers in 4-week-old mice was significantly greater than in 10-, 20-, and 40-week-old mice. There was a strong decrease in differentiation potential of HAP stem cells to cardiac-muscle cells by 10 weeks of age. In contrast, the differentiation potential of HAP stem cells to other cell types did not decrease with age. The possibility of rejuvenation of HAP stem cells to differentiate at high efficiency to cardiac-muscle cells is discussed. 相似文献