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171.
172.
S. Bhattacharyya S. N. Das A. B. Dey K. Nagarkar J. Lobo S. K. Kapoor H. K. Prasad 《Journal of biosciences》1997,22(1):99-109
Interferon-(IFN-γ) has been considered to be a critical protective immunomodulatory component against
Mycobacterium tuberculosis (M. tb.) infection. In this study T-cell proliferation and IFN-γ production upon stimulation with M. tb. were assessed in
patients of pulmonary tuberculosis and healthy contacts. The studies were based on lymphocyte transformation test and detection
of intracellular IFN-γ production by CD4 + ve T-cells by flowcytometry. Patients showed lower levels of proliferation, the
stimulation index being in the range of 2.17 1.1 (mean + SD) compared to the contacts (SI = 4 59±1.6) (P < 0.01). The kinetics
of intracellular induction of IFN-γ on M. tb. stimulation showed a proportional increase in the CD4 + ve T-cell population.
The increase was maximal between 96–120 h of culture. In healthy contacts the number of IFN-γ expressing CD + ve T-cells increased
to 2.5 to 41 × 104 cells/ml in M. tb. stimulated cultures compared to control cultures (0.1 – 15 × 104). In contrast patients showed no/marginal increase in CD4 + ve T-cell population expressing intracellular IFN-γ Thus the
lack of induction of IFN in CD4 + ve T-cells in patients could be a critical shortcoming in their ability to combat tubercle
bacilli infection. 相似文献
173.
174.
Je‐Nie Phue Santosh B. Noronha Ritabrata Bhattacharyya Alan J. Wolfe Joseph Shiloach 《Biotechnology and bioengineering》2005,91(5):649-649
The original article to which this Erratum refers was published in Biotechnol Bioeng 2005;90:805–820 相似文献
175.
176.
A method of extraction of RNA from coffee based on phenol treatment is described. Effectsf of various agents and pH of the extracting buffer on the efficiency of extraction were studied. The best extracting solution is 0·2 M Tris-HCl buffer at pH 7·4 with 1% sodium dodecyl sulphate and 0·05% EDTA. RNA (5–6%) is lost in the tissue residue and 4·6% in the interphase layer. No significant deviation of the spectral characteristics of the RNA solutions obtained from three samples of coffee from that for purified yeast RNA is observed. The purine-pyrimidine ratio for the RNA has been found to be in the range of 1·25–1·38. 相似文献
177.
Thyroid tubulin: purification and properties 总被引:4,自引:0,他引:4
178.
Bhattacharyya P 《Journal of bacteriology》1970,104(3):1307-1311
Accumulation of manganese was measured in subcellular membrane vesicles isolated from Escherichia coli. Accumulation of (54)Mn by vesicles in 0.5 m sucrose is stimulated by glucose and d-lactate and is inhibited by metabolic poisons such as dinitrophenol, m-chlorophenyl carbonylcyanide hydrazone, valinomycin, and nigericin. Manganese uptake by vesicles requires 10 mm calcium, which is not required for uptake of manganese by intact cells. The calcium requirement is specific and cannot be replaced by magnesium, sodium, or potassium. Strontium can replace calcium but is somewhat less effective than calcium. The uptake of manganese is via a manganese-specific system which shows saturation kinetics with manganese with a K(m) of 8 x 10(-6)m and a V(max) of 4 nmoles per min per g (wet weight) at 25 C. Magnesium and calcium do not compete for uptake. The accumulated manganese can be released from the vesicles by lipid active agents such as toluene, and can be exchanged for external manganese. 相似文献
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180.
Purnita Bhattacharyya Bikash Agarwal Madhurankhi Goswami Debasish Maiti Sunandan Baruah Prosun Tribedi 《Antonie van Leeuwenhoek》2018,111(1):89-99
Biofilms are structured consortia of microbial cells that grow on living and non living surfaces and surround themselves with secreted polymers. Infections with bacterial biofilms have emerged as a foremost public health concern because biofilm growing cells can be highly resistant to both antibiotics and host immune defenses. Zinc oxide nanoparticles have been reported as a potential antimicrobial agent, thus, in the current study, we have evaluated the antimicrobial as well as antibiofilm activity of zinc oxide nanoparticles against the bacterium Streptococcus pneumoniae which is a significant cause of disease. Zinc oxide nanoparticles showed strong antimicrobial activity against S. pneumoniae, with an MIC value of 40 μg/ml. Biofilm inhibition of S. pneumoniae was also evaluated by performing a series of experiments such as crystal violet assay, microscopic observation, protein count, EPS secretion etc. using sub-MIC concentrations (3, 6 and 12 µg/ml) of zinc oxide nanoparticles. The results showed that the sub-MIC doses of zinc oxide nanoparticles exhibited significant anti-biofilm activity against S. pneumoniae, with maximum biofilm attenuation found at 12 μg/ml. Taken together, the results indicate that zinc oxide nanoparticles can be considered as a potential agent for the inhibition of microbial biofilms. 相似文献