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131.
132.
Tuberculosis (TB) is more prevalent in the world today than at any other time in human history. Mycobacterium tuberculosis, the pathogen responsible for TB, uses diverse strategies to survive in a variety of host lesions and to evade immune surveillance. A key question is how robust are our approaches to discovering new TB drugs, and what measures could be taken to reduce the long and protracted clinical development of new drugs. The emergence of multi-drug-resistant strains of M. tuberculosis makes the discovery of new molecular scaffolds a priority, and the current situation even necessitates the re-engineering and repositioning of some old drug families to achieve effective control. Whatever the strategy used, success will depend largely on our proper understanding of the complex interactions between the pathogen and its human host. In this review, we discuss innovations in TB drug discovery and evolving strategies to bring newer agents more quickly to patients. 相似文献
133.
Rashmi CHAUHAN Amit Kumar SRIVASTAVA Arvind TRIPATHI Krishna Kant SRIVASTAVA 《自然科学进展(英文版)》2011,21(3):205-210
Amorphous As_2Se_3 chalcogenide thin film was exposed to UV light(i line and g line) using mercury lamp for 30 min. XRD,UV/VIS spectroscopy and thickness measurements were taken for unexposed and exposed thin film for structural and optical characterizations.Linear optical constants(linear refractive index,extinction coefficient and linear optical absorption coefficient) of the film were calculated from transmission spectra using Swanepoel method.Optical bandgap was determined using Tauc's relation of in... 相似文献
134.
The rapid drift of the Indian tectonic plate 总被引:4,自引:0,他引:4
The breakup of the supercontinent Gondwanaland into Africa, Antarctica, Australia and India about 140 million years ago, and consequently the opening of the Indian Ocean, is thought to have been caused by heating of the lithosphere from below by a large plume whose relicts are now the Marion, Kerguelen and Réunion plumes. Plate reconstructions based on palaeomagnetic data suggest that the Indian plate attained a very high speed (18-20 cm yr(-1) during the late Cretaceous period) subsequent to its breakup from Gondwanaland, and then slowed to approximately 5 cm yr(-1) after the continental collision with Asia approximately 50 Myr ago. The Australian and African plates moved comparatively less distance and at much lower speeds of 2-4 cm yr(-1) (refs 3-5). Antarctica remained almost stationary. This mobility makes India unique among the fragments of Gondwanaland. Here we propose that when the fragments of Gondwanaland were separated by the plume, the penetration of their lithospheric roots into the asthenosphere were important in determining their speed. We estimated the thickness of the lithospheric plates of the different fragments of Gondwanaland around the Indian Ocean by using the shear-wave receiver function technique. We found that the fragment of Gondwanaland with clearly the thinnest lithosphere is India. The lithospheric roots in South Africa, Australia and Antarctica are between 180 and 300 km deep, whereas the Indian lithosphere extends only about 100 km deep. We infer that the plume that partitioned Gondwanaland may have also melted the lower half of the Indian lithosphere, thus permitting faster motion due to ridge push or slab pull. 相似文献
135.
Kumar P Wu H McBride JL Jung KE Kim MH Davidson BL Lee SK Shankar P Manjunath N 《Nature》2007,448(7149):39-43
A major impediment in the treatment of neurological diseases is the presence of the blood-brain barrier, which precludes the entry of therapeutic molecules from blood to brain. Here we show that a short peptide derived from rabies virus glycoprotein (RVG) enables the transvascular delivery of small interfering RNA (siRNA) to the brain. This 29-amino-acid peptide specifically binds to the acetylcholine receptor expressed by neuronal cells. To enable siRNA binding, a chimaeric peptide was synthesized by adding nonamer arginine residues at the carboxy terminus of RVG. This RVG-9R peptide was able to bind and transduce siRNA to neuronal cells in vitro, resulting in efficient gene silencing. After intravenous injection into mice, RVG-9R delivered siRNA to the neuronal cells, resulting in specific gene silencing within the brain. Furthermore, intravenous treatment with RVG-9R-bound antiviral siRNA afforded robust protection against fatal viral encephalitis in mice. Repeated administration of RVG-9R-bound siRNA did not induce inflammatory cytokines or anti-peptide antibodies. Thus, RVG-9R provides a safe and noninvasive approach for the delivery of siRNA and potentially other therapeutic molecules across the blood-brain barrier. 相似文献
136.
A single s.c. injection of 20-methylcholanthrene (1 mg in 0.2 ml olive oil) is found to stimulate the relative uptake of uridine-3H by the skin and the s.c. tissue 17- and 3fold respectively, 24 h post-administration. 相似文献
137.
D N Kumar 《Experientia》1978,34(3):397-402
In spectral studies of gamma-irradiated protein-dye complexes, influences of concentrations of the components and changes in dye character are mainly noted. 相似文献
138.
Anurag Kumar Singh Michael P. Manns Ursula Seidler 《Cellular and molecular life sciences : CMLS》2011,68(6):1041-1051
Drug resistance continues to be a stumbling block in achieving better cure rates in several cancers. Doxorubicin is commonly
used in treatment of a wide range of cancers. The aim of this study was to look into the mechanisms of how low ambient pH
may contribute to down-regulation of apoptotic pathways in a gastric tumour cell line. Low pH culture conditions were found
to dramatically prolong cell survival after doxorubicin treatment, an effect that was in part reversed by co-incubation with
the specific p38 mitoge-activated protein kinase (MAP kinase) inhibitor SB203580, only mildly inhibited by blockade of the
multi-drug resistance 1 (MDR1) transporter, but completely abolished by siRNA-mediated knockdown of the heat shock protein
27 (HSP27). In conclusion, acidic pH causes less accumulation of cytotoxic drug in the nucleus of adeno gastric carcinoma
(AGS) cells and HSP27-dependent decrease in FasR-mediated gastric epithelial tumour cell apoptosis. 相似文献
139.
Process planning and scheduling are two major plann in g and control activities that consume significant part of the lead-time, theref ore all attempts are being made to reduce lead-time by automating them. Compute r Aided Process Planning (CAPP) is a step in this direction. Most of the existin g CAPP systems do not consider scheduling while generating a process plan. Sched uling is done separately after the process plan has been generated and therefore , it is possible that a process plan so generated is e... 相似文献
140.
D. Kumar P. Das Gupta S. Bhattacharya 《Cellular and molecular life sciences : CMLS》1973,29(9):1076-1078
Zusammenfassung In der Kopfniere des TeleostiersAnabes testudineus wurde eine besonders hohe Peroxidase-Aktivität nachgewiesen, insbesondere deren Iodid-Oxydation zu Tri-Iodid. 相似文献