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71.
Expression of TGF-beta signaling genes in the normal, premalignant, and malignant human trophoblast: loss of smad3 in choriocarcinoma cells 总被引:8,自引:0,他引:8
We had earlier shown that TGF-beta controls proliferation, migration, and invasiveness of normal human trophoblast cells, whereas premalignant and malignant trophoblast cells are resistant to TGF-beta. To identify signaling defects responsible for TGF-beta resistance in premalignant and malignant trophoblasts, we have compared the expression of TGF-beta signaling molecules in a normal trophoblast cell line (HTR-8), its premalignant derivative (RSVT2/C), and two choriocarcinoma cell lines (JAR and JEG-3). RT-PCR analysis revealed that all these cell lines expressed the mRNA of TGF-beta1, -beta2, and -beta3, TGF-beta receptors type I, II, and III, and post-receptor signaling genes smad2, smad3, smad4, smad6, and smad7 with the exception that TGF-beta2 and smad3 were undetectable in JAR and JEG-3 cells. Immunoblot analysis confirmed the absence of smad3 protein in choriocarcinoma cells. Treatment with TGF-beta1 induced smad3 phosphorylation and smad3 translocation to the nucleus in the normal and premalignant trophoblast cells. These results suggest that loss of smad3 may account for a functional disruption in the TGF-beta signaling pathway in choriocarcinomas, but not in the premalignant trophoblast. 相似文献
72.
P. K. Lala 《Cell proliferation》1972,5(1):79-85
DNA-synthesis (S) times of myelocytes and nucleated erythroid cells in the bone marrow of healthy mice as well as mice bearing advanced Ehrlich ascites tumors were measured with the aid of a combined in vivo-in vitro double isotope labeling technique. Neither the S-period nor the rate of proliferation of these cells were influenced by the presence of the tumor in these hosts. This finding discounts the possibility that the marked retardation of DNA-synthesis and proliferation rate observed in the tumor cells themselves with advancing tumor-age is a nonspecific effect of the nutritional deterioration in the host. 相似文献
73.
Eepsita Priyadarshini Nilotpala Pradhan Lala Behari Sukla Prasanna Kumar Panda Barada Kanta Mishra 《Annals of microbiology》2014,64(3):1055-1063
A biogenic route was adopted towards the synthesis of gold nanoparticles using the extract of a novel strain, Talaromyces flavus. Reduction of chloroauric acid by the fungal extract resulted in the production of gold nanoparticle, which was further confirmed by the concordant results obtained from UV–visible spectroscopy, energy dispersive spectroscopy (EDS), and dynamic light scattering (DLS) analysis. Morphology and the crystal nature of the synthesized nanoparticles were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD) and selected area electron diffraction (SAED). A direct correlation was observed between nanoparticle formation and the concentration of reducing agent present in the fungal extract. The time-dependent kinetic study revealed that the bioreduction process follows an autocatalytic reaction. Crystalline, irregular, and mostly flower-shaped gold nanoparticles with a mean hydrodynamic radius of 38.54?±?10.34 nm were obtained. pH played a significant role on production of mono-dispersed nanoparticle. FTIR analysis partially deciphered the involvement of –NH2, ?SH, and –CO groups as the probable molecules in the bio-reduction and stabilization process. Compared to the conventional methods, a time-resolved, green, and economically viable method for floral-shaped nanoparticle synthesis was developed. 相似文献
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75.
Santosh Kumar Bharti Anu Behari Vinay Kumar Kapoor Niraj Kumari Narendra Krishnani Raja Roy 《Metabolomics : Official journal of the Metabolomic Society》2013,9(1):101-118
Gall bladder tissue specimens obtained from 112 patients were examined by high resolution magic angle spinning (HR-MAS) NMR spectroscopy. Fifty one metabolites were identified by combination of one and two-dimensional NMR spectra. To our knowledge, this is the first report on metabolic profiling of gall bladder tissues using HR-MAS NMR spectroscopy. Metabolic profiles were evaluated for differentiation between benign Chronic Cholecystitis (CC, n = 66) and xantho-granulomatous cholecystitis (XGC, n = 21) and malignant gall bladder cancer (GBC, n = 25). Increase in choline containing compounds, amino acids, taurine, nucleotides and lactate as common metabolites were observed in malignant tissues whereas lipid content was found low as compared to benign tissues. Principal component analysis obtained from the NMR data showed clear distinction between CC and GBC tissue specimens; however, 27 % of XGC tissues were classified with GBC. The partial least square discriminant analysis (PLS-DA) multivariate analysis between benign (CC, XGC) and malignant (GBC) on the training data set (CC; n = 51, XGC; n = 15, GBC; n = 19 tissues specimens) provided 100 % sensitivity and 94.12 % specificity. This PLS-DA model when executed on the spectra of unknown tissue specimens (CC; n = 15, XGC; n = 6, GBC; n = 6) classified them into the three histological categories with more than 95 % of diagnostic accuracy. Non-invasive in vivo MRS technique may be used in future to differentiate between benign (CC and XGC) and malignant (GBC) gall bladder diseases. 相似文献
76.
Henriette Rasolofoarivao Johanna Clémencet Lala Harivelo Raveloson Ravaomanarivo Dimby Razafindrazaka Bernard Reynaud Hélène Delatte 《Experimental & applied acarology》2013,60(4):521-530
Varroa destructor is a major pest in world beekeeping. It was first detected in Madagascar in 2010 on the endemic honeybee Apis mellifera unicolor. To evaluate V. destructor spread dynamics in Madagascar a global survey was conducted in 2011–2012. A total of 695 colonies from 30 districts were inspected for the presence of mites. 2 years after its introduction, nine districts were found infested. Varroa destructor spread was relatively slow compared to other countries with a maximum progression of 40 km per year, the five newly infested districts being located next to the first infested ones. The incidence of mite infestation was also investigated by monitoring 73 colonies from five apiaries during 1 year (2011–2012). Sixty percent of local colony mortality was recorded after 1 year of survey. Varroa destructor strain determination was done by partial sequencing of the cytochrome oxidase I gene of 13 phoretic mites sampled in five districts. A single V. destructor mitochondrial haplotype was detected, the Korean type, also present in the closest African countries. A global pathogen survey was also conducted on the colonies inspected for mite presence. The greater wax moth, Galleria mellonella has been found in all colonies all over the country. Two other pathogens and morphological abnormalities in workers, such as deformed wings, were found associated with only V. destructor presence. A prevention management plan must be implemented to delimit mite spread across the island. 相似文献
77.
Majeed Neelofar Panigrahi Kishore C. S. Sukla Lala Behari John Riffat Panigrahy Madhusmita 《Journal of plant biochemistry and biotechnology.》2020,29(4):665-674
Journal of Plant Biochemistry and Biotechnology - The circadian clock serves the fitness of higher plants by controlling various aspects of plant growth and development ranging from photosynthesis... 相似文献
78.
79.
The reaction of DL-1,3-butadiene diepoxide and of DL-1,4-dibromo-2,3-butanediol with aqueous alkaline sodium arsenite, "Na(3)AsO(3)", gave mixtures of the title arsonic acids which can be separated by anion exchange resin. Characterization of by-products leads to a better understanding of these reactions. These compounds are valuable intermediates for the preparation of novel arsonic acids and bis(arsonic acids). 相似文献
80.
The present study deals with the effects of chronic exposure of low-level microwave radiation on developing rat brain. Starting at 35 days of age, male rats were exposed to 2?h/day for another 35 days to a 16.5-GHz microwave radiation field. After the exposure period, the rats were sacrificed, and brain tissues dissected out and used for biochemical assay. Results showed that exposure to a 16.5-GHz radiation caused significant changes in the activity of protein kinase C as compared to the control group. Furthermore, electron microscopic study revealed an increase in glial cell population. These results confirm that brain cell membrane is an interactive site for electromagnetic field causing an inflammation and possibly tumor promotion. 相似文献