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1.
Summary Using an aeroscope, airborne fungal spores were sampled for two years, 1987–1988 at Tiruchirapalli, Tamil Nadu, India. The aerospora components, their seasonal and annual variations in incidence in the air are discussed and a spore calendar for Tiruchirapalli is presented. 相似文献
2.
Yu-Chi Su Goutham Venkata Naga Davuluri Cheng-Hao Chen Dong-Che Shiau Chien-Chin Chen Chia-Ling Chen Yee-Shin Lin Chih-Peng Chang 《PloS one》2016,11(2)
Hepatocellular carcinoma (HCC) is one of the most common cancers in Taiwan. Although chemotherapy is the primary treatment for HCC patients, drug resistance often leads to clinical failure. Galectin-1 is a beta-galactoside binding lectin which is up-regulated in HCC patients and promotes tumor growth by mediating cancer cell adhesion, migration and proliferation, but its role in chemoresistance of HCC is poorly understood. In this study we found that galectin-1 is able to lead to chemoresistance against cisplatin treatment, and subsequent inhibition has reversed the effect of cell death in HCC cells. Moreover, galectin-1 was found to induce autophagic flux in HCC cells. Inhibition of autophagy by inhibitors or knockdown of Atg5 cancels galectin-1-induced cisplatin resistance in HCC cells. Increase of mitophagy triggered by galectin-1 was found to reduce the mitochondrial potential loss and apoptosis induced by cisplatin treatment. Finally, using an in situ hepatoma mouse model, we clearly demonstrated that inhibition of galectin-1 by thiodigalactoside could significantly augment the anti-HCC effect of cisplatin. Taken together, our findings offer a new insight into the chemoresistance galectin-1 causes against cisplatin treatment, and points to a potential approach to improve the efficacy of cisplatin in the treatment of HCC patients. 相似文献
3.
T. R. Shankar Raman 《Journal of biosciences》1997,22(2):203-218
Chital or axis deer (Axis axis) form fluid groups that change in size temporally and in relation to habitat. Predictions of hypotheses relating animal density,
rainfall, habitat structure, and breeding seasonality, to changes in chital group size were assessed simultaneously using
multiple regression models of monthly data collected over a 2 yr period in Guindy National Park, in southern India. Over 2,700
detections of chital groups were made during four seasons in three habitats (forest, scrubland and grassland). In scrubland
and grassland, chital group size was positively related to animal density, which increased with rainfall. This suggests that
in these habitats, chital density increases in relation to food availability, and group sizes increase due to higher encounter
rate and fusion of groups. The density of chital in forest was inversely related to rainfall, but positively to the number
of fruiting tree species and availability of fallen litter, their forage in this habitat. There was little change in mean
group size in the forest, although chital density more than doubled during the dry season and summer. Dispersion of food items
or the closed nature of the forest may preclude formation of larger groups. At low densities, group sizes in all three habitats
were similar. Group sizes increased with chital density in scrubland and grassland, but more rapidly in the latter—leading
to a positive relationship between openness and mean group size at higher densities. It is not clear, however, that this relationship
is solely because of the influence of habitat structure. The rutting index (monthly percentage of adult males in hard antler)
was positively related to mean group size in forest and scrubland, probably reflecting the increase in group size due to solitary
males joining with females during the rut. The fission-fusion system of group formation in chital is thus interactively influenced
by several factors. Aspects that need further study, such as interannual variability, are highlighted. 相似文献
4.
A bifunctional alpha-amylase/trypsin inhibitor that has two binding sites has been purified from ragi. The inhibitor has been crystallized from its ammonium sulphate solution by the vapour diffusion method. The crystals belong to the orthogonal space group P2(1)2(1)2(1) with unit cell dimensions a = 30.49 A, b = 56.30 A, c = 73.65 A and Z = 4. 相似文献
5.
A comparison of aberration distribution and cell-cycle progression in cells treated with bleomycin with those exposed to X-rays 总被引:1,自引:0,他引:1
The extent of cell-cycle delay and the frequency of aberrant metaphases induced by bleomycin (BLM) and X-rays have been compared at doses which produce similar frequencies of chromosome aberrations by the 2 clastogenic agents (BLM, 40 micrograms/ml and X-rays, 2 Gy) in muntjac lymphocytes. The frequency of aberrant metaphases was low in BLM-treated cells; however, the number of aberrations per metaphase was higher than in cells exposed to X-rays. Thus in contrast to their uniform sensitivity to X-rays, the lymphocytes showed differential sensitivity to BLM. This might be due to differences among the cells in their uptake of BLM and/or its action on the nuclear membrane-DNA complex. In spite of the total number of chromosome aberrations being similar to that induced by X-rays, BLM did not induce a significant delay in cell-cycle progression as observed in the case of X-rays. A possible explanation could be that the DNA damages being limited to fewer cells than in the case of X-irradiation, the BLM-treated cultures had more normal cells allowing faster progression and/or unlike X-rays BLM may not be causing other cellular damages in addition to DNA breaks. 相似文献
6.
The X and Y chromosomes of the musk shrew are the two largest in the complement and they regularly form a single chiasma during meiosis. This chiasma is located in the short arms of the X and Y, both of which show partial C-banding at meiosis. The in vitro incorporation of 5-bromodeoxyuridine/tritiated thymidine during late S reveals that the non-C-band region of the Y finishes replication later than the C-band positive heterochromatin. During meiosis, the sex bivalent opens out early in pachytene to reveal a single chiasma which persists until late metaphase-I. In surface-spread, silver-stained meiocytes, the sex bivalent morphology changes from a phase of extensive pairing to one which includes a visible chiasma through a brief diffuse stage. Observations on C-banded meiocytes show a shift in the sex pair from a C-band positive to a negative state as compared to their corresponding somatic pattern. Comparable changes are also observed in the sex bivalents of other mammals which undergo a chiasmatic exchange. This suggests that in addition to pairing homology, an alteration in the chromatin configuration may be necessary for crossing over to occur between the sex chromosomes. 相似文献
7.
M. Joginadha Swamy M. Venkata Krishna Sastry Avadhesha Surolia 《Journal of biosciences》1985,9(3-4):203-212
Secondary structure prediction for the 4 legume lectins: Concanavalin A, soybean agglutinin, favabean lectin and lentil lectin,
was done by the method of Chou and Fasman. This prediction shows that these four lectins fall into a structurally distinct
class of proteins, containing high amounts of β-sheet and β-turns. There is a notable similarity in the gross structure of
these proteins; all four of them contain about 40–50% of β-sheet, 35–45 % β-turn and 0–10% of α-helix. When the secondary
structure of corresponding residues in each pair of these lectins was compared, there was a striking similarity in the Concanavalin
A-soybean agglutinin and favabean lectin-lentil lectin pairs, and considerably less similarity in the other pairs, suggesting
that these legume lectins have probably evolved in a divergent manner from a common ancestor. A comparison of the predicted
potential β-turn sites also supports the hypothesis of divergent evolution in this class of lectins. 相似文献
8.
9.
Starting from the laws of thermodynamics of reversible processes, a temperature-dependent constitutive equation is derived for the elastic force-length relation of soft biological tissues. These tissues are composed of a network of fibres (mainly collagen). The equation is based on a model which uses a simplified two-dimensional representation of the alpha-helix of collagen. 相似文献
10.
A Raman K L Bhatia T P Singh A Srinivasan C Betzel R C Malik 《Archives of biochemistry and biophysics》1992,294(1):319-321
Lactotransferrin is an iron-binding protein. It has been purified from buffalo colostrum. The purified lactotransferrin has been crystallized in 10% ethanol solution. The crystals are orthorhombic and the space group is P2(1)2(1)2(1) with unit cell dimensions a = 161.70 A, b = 155.75 A, c = 113.48 A. The asymmetric unit contains three molecules of the protein with a solvent content of about 59%. The crystals were stable in the X-ray beam and diffract beyond 3.5 A resolution. The native data have been collected and the structure determination is in progress. 相似文献