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181.
Ramchiary N Padmaja KL Sharma S Gupta V Sodhi YS Mukhopadhyay A Arumugam N Pental D Pradhan AK 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,115(6):807-817
Quantitative trait loci (QTL) analysis of yield influencing traits was carried out in Brassica juncea (AABB) using a doubled haploid (DH) mapping population of 123 lines derived from a cross between Varuna (a line representing
the Indian gene pool) and Heera (representing the east European gene pool) to identify potentially useful alleles from both
the parents. The existing AFLP based map of B. juncea was further saturated with RFLP and SSR markers which led to the identification of the linkage groups belonging to the A
(B. rapa) and B (B. nigra) genome components of B. juncea. For QTL dissection, the DH lines were evaluated at three different environments and phenotyped for 12 quantitative traits.
A total of 65 QTL spread over 13 linkage groups (LG) were identified from the three environments. QTL analysis showed that
the A genome has contributed more than the B genome to productivity (68% of the total QTL detected) suggesting a more prominent
role of the A genome towards domestication of this crop. The east European line, Heera, carried favorable alleles for 42%
of the detected QTL and the remaining 58% were in the Indian gene pool line, Varuna. We observed clustering of major QTL in
a few linkage groups, particularly in J7 and J10 of the A genome, with QTL of different traits having agronomically antagonistic
allelic effects co-mapping to the same genetic interval. QTL analysis also identified some well-separated QTL which could
be readily transferred between the two pools. Based on the QTL analysis, we propose that improvement in yield could be achieved
more readily by heterosis breeding rather than by pure line breeding.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
182.
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184.
Arvind Gulati Natasha Sharma Pratibha Vyas Swati Sood Praveen Rahi Vijaylata Pathania Ramdeen Prasad 《Archives of microbiology》2010,192(11):975-983
An efficient phosphate-solubilizing plant growth–promoting Acinetobacter rhizosphaerae strain BIHB 723 exhibited significantly higher solubilization of tricalcium phosphate (TCP) than Udaipur rock phosphate (URP),
Mussoorie rock phosphate (MRP) and North Carolina rock phosphate (NCRP). Qualitative and quantitative differences were discerned
in the gluconic, oxalic, 2-keto gluconic, lactic, malic and formic acids during the solubilization of various inorganic phosphates
by the strain. Gluconic acid was the main organic acid produced during phosphate solubilization. Formic acid production was
restricted to TCP solubilization and oxalic acid production to the solubilization of MRP, URP and NCRP. A significant increase
in plant height, shoot fresh weight, shoot dry weight, root length, root dry weight, and root, shoot and soil phosphorus (P)
contents was recorded with the inoculated treatments over the uninoculated NP0K or NPTCPK treatments. Plant growth promotion as a function of phosphate solubilization suggested that the use of bacterial strain
would be a beneficial addition to the agriculture practices in TCP-rich soils in reducing the application of phosphatic fertilizers. 相似文献
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186.
In the present study, the newly synthesized TRH analog (l-pGlu-(2-propyl)-l-His-l-ProNH2; NP-647) was evaluated for its effects in in vitro (oxygen glucose deprivation (OGD)-, glutamate- and H2O2-induced injury in PC-12 cells) and in vivo (transient global ischemia) models of cerebral ischemic injury. PC-12 cells were subjected to oxygen and glucose deprivation for 6 h. Exposure of NP-647 was given before and during OGD. In glutamate and H2O2 induced injury, exposure of NP-647 was given 1, 6 and 24 h prior to exposure of glutamate and H2O2 exposure. NP-647, per se found to be non-toxic in 1-100 μM concentrations. NP-647 showed protection against OGD at the 1 and 10 μM. The concentration-dependent protection was observed in H2O2- and glutamate-induced cellular injury. In in vivo studies, NP-647 treatment showed protection of hippocampal (CA1) neuronal damage in transient global ischemia in mice and subsequent improvement in memory retention was observed using passive avoidance retention test. Moreover, administration of NP-647 resulted in decrease in inflammatory cytokines TNF-α and IL-6 as well as lipid peroxidation. These results suggest potential of NP-647 in the treatment of cerebral ischemia and its neuroprotective effect may be attributed to reduction of excitotoxicity, oxidative stress and inflammation. 相似文献
187.
Upreti M Jamshidi-Parsian A Koonce NA Webber JS Sharma SK Asea AA Mader MJ Griffin RJ 《Translational oncology》2011,4(6):365-376
Classic cancer research for several decades has focused on understanding the biology of tumor cells in vitro. However, extending these findings to in vivo settings has been impeded owing to limited insights on the impact of microenvironment on tumor cells. We hypothesized that tumor cell biology and treatment response would be more informative when done in the presence of stromal components, like endothelial cells, which exist in the tumor microenvironment. To that end, we have developed a system to grow three-dimensional cultures of GFP-4T1 mouse mammary tumor and 2H11 murine endothelial cells in hanging drops of medium in vitro. The presence of 2H11 endothelial cells in these three-dimensional cocultures was found to sensitize 4T1-GFP tumor cells to chemotherapy (Taxol) and, at the same time, protect cells from ionizing radiation. These spheroidal cultures can also be implanted into the dorsal skinfold window chamber of mice for fluorescence imaging of vascularization and disease progression/treatment response. We observed rapid neovascularization of the tumor-endothelial spheroids in comparison to tumor spheroids grown in nude mice. Molecular analysis revealed pronounced up-regulation of several proangiogenic factors in the tumor tissue derived from the tumor-endothelial spheroids compared with tumor-only spheroids. Furthermore, the rate of tumor growth from tumor-endothelial spheroids in mice was faster than the tumor cell-only spheroids, resulting in greater metastasis to the lung. This three-dimensional coculture model presents an improved way to investigate more pertinent aspects of the therapeutic potential for radiation and/or chemotherapy alone and in combination with antiangiogenic agents. 相似文献
188.
Four different food matrices (alfalfa, cilantro, mamey sapote, and mung bean) were contaminated with three different dilutions
106, 104, and 103 cfu/g of Yersinia enterocolitica. DNA was isolated from each food mix and used in chromosomal amplifications. The amplified DNA was used as templates in single
PCR reactions of the four genes (virF, ail, yst, and blaA) followed by mixing the four reactions for one PCR primer extension reaction. The presence and the limit of detection of
four genes in four food matrices were established by microarray hybridization. Data revealed the diversity of signal intensities.
Neither the microarray chip hybridization nor the single PCR amplification could detect virF’s presence located on a plasmid. Ail was detected in 103 cfu/g, whereas blaA and yst were detected from 105 to 106 cfu/g in all food matrices. Therefore, the ail gene could be the gene of choice in identifying Y. enterocolitica in alfalfa, cilantro, mamey, and mung bean. Other genes—blaA, yst, virF—exhibited wide variability in hybridization signals, highlighting the need of a better DNA purification step prior to DNA
microarray hybridization. 相似文献
189.
190.
M Boschmann U Kreuzberg S Engeli F Adams G Franke S Klaua J Scholze G Weidinger F C Luft A M Sharma J Jordan 《Hormones et métabolisme》2006,38(5):323-329
AT1 receptor blockers and ACE inhibitors decrease the risk for new onset diabetes mellitus. The phenomenon could be related to a direct angiotensin II effect on tissue metabolism. To address the issue, we recruited eighteen obese hypertensive patients. Patients were randomized to double-blind treatment with either valsartan (n = 8) or atenolol (n = 10) for thirteen weeks. They underwent an oral glucose tolerance test before and during active treatment, while metabolism was monitored through subcutaneous and intramuscular microdialysis and indirect calorimetry. After glucose ingestion, venous glucose and insulin concentrations increased rapidly while systemic free fatty acid concentrations were suppressed. Dialysate glucose and lactate concentrations increased briskly in adipose tissue and in skeletal muscle. Dialysate glycerol decreased profoundly in both tissues. Respiratory quotient increased markedly after glucose ingestion. These responses were identical at baseline and during active treatment either drug. We conclude that AT1 receptor blockade in obese hypertensive patients has no effect on interstitial glucose supply, lipolysis, and substrate oxidation. One possible explanation is that angiotensin II levels in obese hypertensives are not sufficient to elicit the metabolic changes that have been observed after direct angiotensin II application. The exact mechanism by which inhibition of the renin-angiotensin-aldosterone system decreases the diabetes risk remains unresolved and requires further study. 相似文献