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921.
本文采用文献计量的方法,统计了我国植物分类学各分支学科的有关文献。并对各类文献数量和内容构成的变化进行了分析。 相似文献
922.
Mutations in the GTP-binding site of GS alpha alter stimulation of adenylyl cyclase 总被引:17,自引:0,他引:17
S B Masters R T Miller M H Chi F H Chang B Beiderman N G Lopez H R Bourne 《The Journal of biological chemistry》1989,264(26):15467-15474
Mutational replacements of specific residues in the GTP-binding pocket of the 21-kDa ras proteins (p21ras) reduce their GTPase activity. To test the possibility that the cognate regions of G protein alpha chains participate in GTP binding and hydrolysis, we compared signaling functions of normal and mutated alpha chains (termed alpha s) of Gs, the stimulatory regulator of adenylyl cyclase. alpha s chains were expressed in an alpha s-deficient S49 mouse lymphoma cell line, cyc-. alpha s in which leucine replaces glutamine 227 (corresponding to glutamine 61 of p21ras) constitutively activates adenylyl cyclase and reduces the kcat for GTP hydrolysis more than 100-fold. There is a smaller reduction in GTPase activity in another mutant in which valine replaces glycine 49 (corresponding to glycine 12 of p21ras). This mutant alpha s is a poor activator of adenylyl cyclase. Moreover, the glycine 49 protein, unlike normal alpha s, is not protected against tryptic cleavage by hydrolysis resistant GTP analogs; this finding suggests impairment of the mutant protein's ability to attain the active (GTP-bound) conformation. We conclude that alpha s residues near glutamine 227 and glycine 49 participate in binding and hydrolysis of GTP, although the GTP binding regions of alpha s and p21ras are not identical. 相似文献
923.
Genome-wide analysis of T-DNA integration into the chromosomes of Magnaporthe oryzae 总被引:1,自引:0,他引:1
924.
Human disease studies using DNA microarrays in both clinical/observational and experimental/controlled studies are having increasing impact on our understanding of the complexity of human diseases. A fundamental concept is the use of gene expression as a “common currency” that links the results of in vitro controlled experiments to in vivo observational human studies. Many studies – in cancer and other diseases – have shown promise in using in vitro cell manipulations to improve understanding of in vivo biology, but experiments often simply fail to reflect the enormous phenotypic variation seen in human diseases. We address this with a framework and methods to dissect, enhance and extend the in vivo utility of in vitro derived gene expression signatures. From an experimentally defined gene expression signature we use statistical factor analysis to generate multiple quantitative factors in human cancer gene expression data. These factors retain their relationship to the original, one-dimensional in vitro signature but better describe the diversity of in vivo biology. In a breast cancer analysis, we show that factors can reflect fundamentally different biological processes linked to molecular and clinical features of human cancers, and that in combination they can improve prediction of clinical outcomes. 相似文献
925.
926.
So Jin Park Jeong Hoon Yang Hyo Jung Park Yong Won In Young Mi Lee Yang Hyun Cho Chi Ryang Chung Chi-Min Park Kyeongman Jeon Gee Young Suh 《PloS one》2015,10(11)
To investigate the appropriateness of the current vancomycin dosing strategy in adult patients with extracorporeal membrane oxygenation (ECMO), between March 2013 and November 2013, patients who were treated with vancomycin while on ECMO were enrolled. Control group consisted of 60 patients on vancomycin without ECMO, stayed in medical intensive care unit during the same study period and with the same exclusion criteria. Early trough levels were obtained within the fourth dosing, and maintenance levels were measured at steady state. A total of 20 patients were included in the analysis in ECMO group. Sixteen patients received an initial intravenous dose of 1.0 g vancomycin followed by 1.0 g every 12 hours. The non-steady state trough level of vancomycin after starting administration was subtherapeutic in 19 patients (95.00%) in ECMO group as compared with 40 patients (66.67%) in the control group (p = 0.013). Vancomycin clearance was 1.27±0.51 mL/min/kg, vancomycin clearance/creatinine clearance ratio was 0.90 ± 0.37, and elimination rate constant was 0.12 ± 0.04 h-1. Vancomycin dosingfrequency and total daily dose were significantly increased after clinical pharmacokinetic services of the pharmacist based on calculated pharmacokinetic parameters (from 2.10 ± 0.72 to 2.90 ± 0.97times/day, p = 0.002 and from 32.54 ± 8.43 to 42.24 ± 14.62mg/kg, p = 0.014) in ECMO group in contrast with those (from 2.11 ± 0.69 to 2.37 ± 0.86 times/day, p = 0.071 and from 33.91 ± 11.85 to 31.61 ± 17.50 mg/kg, p = 0.350) in the control group.Although the elimination rate for vancomycin was similar with population parameter of non ECMO patients, the current dosing strategy of our institution for vancomycinin our ICU was not sufficient to achieve the target trough in the initial period in most patients receiving ECMO. 相似文献
927.
928.
As our understanding of onset and progress of diseases at the genetic and molecular level rapidly progresses, the potential of advanced technologies, such as 3D-printing, Socially-Assistive Robots (SARs) or augmented reality (AR), that are applied to personalized nanomedicines (PNMs) to alleviate pathological conditions, has become more prominent. Among advanced technologies, AR in particular has the greatest potential to address those challenges and facilitate the translation of PNMs into formidable clinical application of personalized therapy.As AR is about to adapt additional new methods, such as speech, voice recognition, eye tracing and motion tracking, to enable interaction with host response or biological systems in 3-D space, a combination of multiple approaches to accommodate varying environmental conditions, such as public noise and atmosphere brightness, will be explored to improve its therapeutic outcomes in clinical applications. For instance, AR glasses still being developed by Facebook or Microsoft will serve as new platform that can provide people with the health information they are interested in or various measures through which they can interact with medical services.This review has addressed the current progress and impact of AR on PNMs and its application to the biomedical field. Special emphasis is placed on the application of AR based PNMs to the treatment strategies against senior care, drug addiction and medication adherence. 相似文献
929.
930.
Srdjan M. Vlajkovic Kyu-Hyun Lee Ann Chi Yan Wong Cindy X. Guo Rita Gupta Gary D. Housley Peter R. Thorne 《Purinergic signalling》2010,6(2):273-281
Hearing loss from noise exposure is a leading occupational disease, with up to 5% of the population at risk world-wide. Here,
we present a novel purine-based pharmacological intervention that can ameliorate noise-induced cochlear injury. Wistar rats
were exposed to narrow-band noise (8–12 kHz, 110 dB SPL, 2–24 h) to induce cochlear damage and permanent hearing loss. The
selective adenosine A1 receptor agonist, adenosine amine congener (ADAC), was administered intraperitoneally (100 μg/kg/day) at time intervals after
noise exposure. Hearing thresholds were assessed using auditory brainstem responses and the hair cell loss was evaluated by
quantitative histology. Free radical damage in the organ of Corti was assessed using nitrotyrosine immunohistochemistry. The
treatment with ADAC after noise exposure led to a significantly greater recovery of hearing thresholds compared with controls.
These results were upheld by increased survival of sensory hair cells and reduced nitrotyrosine immunoreactivity in ADAC-treated
cochlea. We propose that ADAC could be a valuable treatment for noise-induced cochlear injury in instances of both acute and
extended noise exposures. 相似文献