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971.
Nicastro G Masino L Frenkiel TA Kelly G McCormick J Menon RP Pastore A 《Journal of biomolecular NMR》2004,30(4):457-458
972.
An acid pellet, obtained as a side fraction from a conventional gonadotropin purification pathway, has been found to contain the bulk of the pituitary lactogenic hormones (growth hormone or GH and prolactin or PRL). This discarded side fraction has been utilized to obtain buffalo lactogenic hormones (buGH and buPRL), simultaneously, and in bulk. The immunoreactivities of the purified semi-pure buffalo GH and PRL (APECS and APP-I, respectively) preparations were compared by direct binding ELISA with semi-pure standard buGH and PRL (ECS and EP-I, respectively) and were found to be as pure as standard semi-pure buGH and buPRL. When checked by direct binding ELISA using buGH and buPRL antisera, it was observed that APECS and APP-I were not cross-immunoreactive. SDS-PAGE and western blot analysis of APECS and APP-I showed major bands located at the same positions as in the case of standard semi-pure preparations (20 kDa for APECS and 23 kDa for APP-I). The semi-purified buGH and buPRL (APECS and APP-I) were converted to a highly purified preparation by chromatographing them via Sephacryl S-200 gel-filtration chromatography. 相似文献
973.
Though polyethylenimine (PEI) is one of the most efficient nonviral vectors, one concern is the significant cytotoxicity of free PEI that represents about 80% of the PEI molecules in PEI/DNA mixtures used for transfection. In this respect, the aim of this work was to further investigate the intracellular fate of PEI during transfection of L929 fibroblasts. To this end, we analyzed by fluorescence correlation spectroscopy (FCS) using two-photon excitation the intracellular concentration and diffusion properties of labeled PEI and PEI/DNA complexes in various compartments of L929 cells. High initial fluorescence intensity, rapid photobleaching and the absence of measurable autocorrelation curves in most selected locations in cytoplasm suggest that PEI/DNA complexes and PEI accumulate (up to 30 times the concentration in the extracellular medium) in late endosomes bound to the inner membrane face. This feature, together with membrane destabilizing properties of PEI, may explain the release of PEI into cytoplasm and subsequent diffusion into the nucleus. In the nucleus, the concentration of PEI was found to be about 2.5- to 3.5-fold higher than the one in the incubation medium. Moreover, autocorrelation curves obtained in the nuclear compartment can be analyzed with either a two-component model (with the major fraction undergoing free Brownian diffusion) or an anomalous diffusion model. Both the endosomal disruption and the large intranuclear PEI concentration may contribute to PEI cytotoxicity. 相似文献
974.
975.
Instructions for authors 总被引:2,自引:0,他引:2
Although Helicobacter pylori infects 50% of the total human population, only a small fraction of the infected people suffer from severe diseases like peptic ulcers and gastric adenocarcinoma. H. pylori strains, host genotypes and environmental factors play important role in deciding the extent and severity of the gastroduodenal diseases. The bacteria has developed a unique set of virulence factors to survive in the extreme ecological niche of human stomach. Together these virulence factors make H. pylori one of the most successful human pathogenic bacteria colonizing more than half of the human population. Understanding the mechanism of action of the major H. pylori virulence factors will shed light into the molecular basis of its pathogenicity. 相似文献
976.
Conclusion In this study, we found that both heating temperature and heating time affect mean particle size, particle size distribution,
and drug entrapment efficiency of albumin microspheres. The change in heating temperature may affect the particle size of
the product, especially when heating is carried out at a lower temperature (90°C–120°C). Hence the temperature should be selected
on the basis of desired size range. Given that it is desirable for a maximum amount of the drug used in the preparation to
become entrapped in microspheres, heating temperature and heating time for denaturation of albumin should be selected cautiously,
as both have a significant effect on drug entrapment efficiency. In the present case, the highest entrapment was found in
batches prepared by heating at 90°C for 5 minutes. However, the extent of stabilization at the selected temperature and the
time of heating should also be taken into consideration, as they may affect the release of drugs to target tissue. 相似文献
977.
NaCl-induced changes in the thylakoid membrane of wild-type Anabaena variabilis and its NaClr mutant strain have been studied. Biochemical characterization of the thylakoid membrane was done by taking its absorption
and fluorescence spectra at different wavelength. The thylakoid membranes of both strains were isolated by mechanical disruption
of the freeze-dried and lysozyme-treated cells, followed by differential and density gradient centrifugation. The light absorption
spectra of the thylakoid membrane showed three and two peaks in NaClr mutant strain and its wild-type counterpart respectively at wavelengths of 400–850 nm. These peaks revealed that the thylakoid
membrane contains a large amount of carotenoid and chlorophyll a. Fluorescence emission spectra of thylakoid membrane of NaClr mutant and its wild-type strain at excitation wavelength of 335 nm showed two different peaks, one at 340 nm and the other
at 663 nm respectively. The light absorption and fluorescence spectra of the thylakoid membrane also revealed that the membrane
contained carotenoid pigment, chlorophyll (Chl) a, and a pigment with an emission peak at 335 nm. The HPLC analysis of the pigments of the thylakoid membrane indicates that
the NaClr mutant strain under NaCl stress contained an additional peak for the carotenoid pigment, which was lacking in its wild-type
counterpart. The major peak in thylakoid membrane was that of echinenone and β-carotene. Whereas the polypeptide composition
of thylakoid membrane differed in the wild-type and its NaClr mutant strain, no difference in the cell wall protein pattern was observed in both strains. The thylakoid membrane of NaClr mutant strain contained two additional protein bands that were absent in its wild-type counterpart. The thylakoid membrane
of the wild-type and its NaClr mutant strain also showed morphological variations under NaCl stress.
Received: 14 April 2000 / Accepted: 23 May 2000 相似文献
978.
C-fos mRNA Induction in the Central and Peripheral Nervous Systems of Diisopropyl Phosphorofluoridate (DFP)-Treated Hens 总被引:1,自引:0,他引:1
A single dose of diisopropyl phosphorofluoridate (DFP), an organophosphorus ester, produces delayed neurotoxicity (OPIDN) in hen. DFP produces mild ataxia in hens in 7–14 days, which develops into severe ataxia or paralysis as the disease progresses. Since, OPIDN is associated with alteration in the expression of several proteins (e.g., Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) -subunit, tau, tubulin, neurofilament (NF) protein, vimentin, GFAP) as well as their mRNAs (e.g., NF, CaM kinase II -subunit), we determined the effect of a single dose of DFP on the expression of one of the best known immediate-early gene (IEG), c-fos. C-fos expression was measured by Northern hybridization in cerebrum, cerebellum, brainstem, midbrain, spinal cord, and the sciatic nerves of hens at 0.5 hr, 1 hr, 2 hr, 1 day, 5 days, 10 days, and 20 days after a single 1.7 mg/kg, sc. injection of DFP. All the tissues (cerebrum, 52%; cerebellum, 55%; brainstem, 49%; midbrain, 23%; spinal cord, 80%; sciatic nerve, 157%;) showed significant increase in c-fos expression in 30 min and this elevated level persisted at least up to 2 hr. Expressions of -actin mRNA and 18S RNA were used as internal controls. The significant increase in c-fos expression in DFP-treated hens suggests that c-fos may be one of the IEGs involved in the development of OPIDN.Both of them equally contributed towards this work 相似文献
979.
Shah Krushali Chadotra Swapnil Tanwar Sudeep Gupta Rajesh Kumar Neeraj 《Cluster computing》2022,25(3):1927-1955
Cluster Computing - In this era of modern digital technologies, the Internet of Vehicles (IoVs) is omnipresent and can be used for varied purposes. However, these devices have scalability,... 相似文献
980.