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981.
Methylglyoxal (MG) is a highly reactive α-oxoaldehyde, demonstrating anticancer effect on plant neoplastic tumours. In in vivo studies it was observed that MG destroyed crown gall tumours in Nicotiana tabacum produced by Agrobacterium tumefaciens, without any adverse effect on the host. The efficacy of MG in comparison to other anticancer drugs viz. cisplatin and ellagic acid in the treatment of crown gall was investigated. A slight degeneration of galls was noted in
plants treated with cisplatin and ellagic acid but the plants died subsequently. With MG however, crown galls were completely
cured and the plants completed their usual life cycle by flowering and producing seeds. MG inhibited the respiration of crown
gall calluses suggesting that energy depletion resulted in tumour destruction. 相似文献
982.
Sukla Sengupta 《Review of Palaeobotany and Palynology》1977,24(5):239-246
The gradual degradation of three types of pollen exines from different plant groups (gymnosperms and angiosperms) with rising temperature has been observed and comparisons made. Pollen grains are heated to different temperatures (100°C–350°C) in a sealed copper tube, placed in a nichrome wire resistance furnace. In each case the pollen grains are heated for 100 hours.The colour change and the size reduction with rising temperature are common to all pollen types. The sexine or ornamented part of the pollen exine is affected first by rising temperature. In angiosperm pollen, the sexibe pattern is not recognisable at 300°C, but pine pollen retains its pattern up to 350°C. The nexine seems to be more stable at high temperatures than the sexinous elements and either remains unaltered with remnants of the sexinous pattern, or becomes altered and amorphous.The lamellar part of the nexine appears to be important and the evolutionary significance of the exine is discussed. The present work shows that the gymnosperm pollen has more stable exines, and may be better adapted for survival than angiosperm exines. 相似文献
983.
Anirban Sengupta Tarun Keswani Samrat Sarkar Soubhik Ghosh Saikat Mukherjee Arindam Bhattacharyya 《Microbes and infection / Institut Pasteur》2019,21(10):475-484
Splenic plasmacytoid dendritic cells (pDC) possess the capability to harbor live replicative Plasmodium parasite. Isolated splenic pDC from infected mice causes malaria when transferred to naïve mice. Incomplete autophagic degradation might cause poor antigen processing and poor immune response. Induction of autophagic flux by rapamycin treatment led to better prognosis by boosting pDC centered immune response against the pathogen. Splenic pDC from rapamycin-treated infected mice, caused less parasitemia in naïve mice. The downregulation of adhesion with unaltered phagocytic potential of the cells post autophagic induction restricted excessive parasite burden within them. Rapamycin-treated pDC played a better role in antigen presentation. They showed higher expression of co-stimulatory molecules CD80, CD86, DEC205, MHCI. Rapamycin-treated pDC induced CD28 expression on CD8+ T cells and suppressed FasL level. This cells also influenced differentiation of effector, memory T cell population. The increase in IL10: TNFα ratio, Treg: Th17 ratio and lowering of myeloid DC: plasmacytoid DC ratio was observed. It shifted the overaggressive inflammation mediated Th1 pathway that is reported to incur host damage, to a better well-balanced cytokine profile exhibiting Th2 pathway. Autophagic flux induction within pDC proved to be beneficial in combating malarial pathogenicity. 相似文献
984.
985.
Aryadeep Roychoudhury Supratim Basu Dibyendu N. Sengupta 《Acta Physiologiae Plantarum》2009,31(5):915-926
The poor productivity and local confinement of indigenous aromatic rice varieties are mostly due to their susceptibility to
salinity/drought/abscisic acid (ABA)-mediated abiotic stresses. It is thus essential to study the effects of several stress
factors on their physiological parameters so as to improve their tolerance mechanism and enhance their global demand. Previously,
we studied the effect of salinity stress on the physiological and molecular responses of the common aromatic rice Gobindobhog.
The objective of this study was to understand the influence of exogenous ABA on some biochemical parameters in Gobindobhog,
and comparison with those from non-aromatic M-1-48 and Nonabokra rice. The highest endogenous hydrogen peroxide content and
membrane lipid peroxidation (increased malondialdehyde and lipoxygenase activity) were found in ABA-treated Gobindobhog leaves.
While the catalase activity was down regulated the most in ABA-treated Gobindobhog leaves, the guaiacol peroxidase activity
was induced maximally, indicating the protective role of peroxidase rather than catalase, during ABA-induced oxidative damages.
The antioxidant, anthocyanin, showed the highest level in ABA-treated Nonabokra. Enhanced cysteine, following ABA exposure
and the highest levels of reducing sugars, total amino acids, proline, and polyamines (putrescine and spermidine) recorded
in Gobindobhog, probably served to shield from ABA-induced stress injuries, whereas the spermine levels were comparable in
ABA-treated Nonabokra and Gobindobhog. The aroma content, intensified after ABA treatment, was markedly noted in Gobindobhog.
Thus, the systematic examination of ABA-mediated stress revealed the most prominent oxidative damages in Gobindobhog, even
higher than M-1-48, with a concomitant enhancement in peroxidase system and particularly osmolyte or polyamine levels to ensure
its sustenance. 相似文献
986.
A K Sarkar A Chakraborti U K Saha S K Bose D Sengupta 《Indian journal of experimental biology》1989,27(9):802-804
In vitro effects of aspirin and paracetamol at the doses 200, 400, 600, 800 nmole/mg protein on ATPases activity were studied in the cerebrum and cerebellum of human fetus covering the age range from 10 weeks to 32 weeks of gestation. Both aspirin and paracetamol inhibit Na+K+ ATPase and Mg2+ ATPase in a dose dependent manner. The inhibition of Na+K+ ATPase and Mg2+ ATPase activity which may affect the release and uptake of biogenic amines in CNS, hinders the maturation of human fetal brain. 相似文献
987.
T M Bakir A Hossain S De-Silva A Siddiqui B S Sengupta M M el-Sheikh A F Bakir 《Journal of hygiene, epidemiology, microbiology, and immunology》1989,33(2):189-197
An enzyme immunoassay (EIA) in parallel with cell culture was used to investigate the extent of infections due to Chlamydia trachomatis. EIA reactive confirmed in cell culture was taken as positive. C. trachomatis was found in 6 (26.0%) of 23 men with symptomatic non-gonococcal urethritis (NGU), ten (17.2%) of 58 symptom-free males and in three of 4 with postgonococcal urethritis. Among 106 asymptomatic pregnant women studied the incidence of C. trachomatis was 8.5% while a higher incidence (16.7%) was found in those with symptoms. C. trachomatis positivity in asymptomatic and symptomatic post-natal screening were 11.4% and 7.7%. Of 43 symptomatic non-pregnant females investigated, 7 (16.3%) were found to be positive for C. trachomatis. Of 3 women with PID, 2 (66.7%) harboured C. trachomatis in their cervix while in another 29 infertile women, C. trachomatis was positive in 3 (8.1%). Contraceptives appeared to have an effect on the chlamydial positivity. Comparative testing of EIA with the standard cell culture method in this study indicate EIA as a suitable alternative for the definitive diagnosis of chlamydial infection in high prevalence settings and with caution in low prevalence settings. 相似文献
988.
H Dutta M Sengupta A Ghosh C Sengupta A U De 《Indian journal of biochemistry & biophysics》1991,28(3):210-213
To correlate lipophilicity of lignocaine with changes in lipid composition of blood as a result of in vitro incubation with the drug, phosphorus content and fatty acid compositions of blood lipids before and after lignocaine treatment have been compared with those of a standard phospholipid, lecithin, under similar conditions of drug treatment. The change in fatty acid constituents has been correlated with the biological activity (both therapeutic and toxic) of lignocaine. 相似文献