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941.
Fangyou Yu Ying Liu Yuanyuan Xu Yongpeng Shang Danping Lou Zhiqiang Qin Chris Parsons Wu Zhou Xiaoying Huang Yuping Li Longhua Hu Liangxing Wang 《PloS one》2013,8(12)
Panton-Valentine leukocidin (PVL; gene designation lukF/S-PV) is likely an important virulence factor for Staphylococcus aureus (S. aureus), as qualitative expression of the protein correlates with severity for specific clinical presentations, including skin and soft tissue infections (SSTIs). Development of genetic approaches for risk-assessment of patients with S. aureus infections may prove clinically useful, and whether lukF/S-PV gene expression correlates with specific clinical presentations for S. aureus has been largely unexplored. In the present study, we quantified lukS-PV mRNA among 96 S. aureus isolates to determine whether expression levels correlated with specific clinical presentations in adults and children. Expression level of lukS-PV mRNA among isolates from skin and soft tissue infections (SSTIs) was significantly greater than among isolates from blood stream infection (BSIs), and expression level of lukS-PV mRNA among BSI isolates from children was significantly greater than for BSI isolates among adults. Moreover, expression level of lukS-PV mRNA among community-acquired (CA) isolates was significantly greater than for hospital-acquired (HA) isolates. These data justify additional studies to determine the potential clinical utility for lukS-PV mRNA quantification as a predictive tool for severity of S. aureus infection. 相似文献
942.
Min Zhang Wenting Luo Bo Huang Zihui Liu Limei Sun Qingfu Zhang Xueshan Qiu Ke Xu Enhua Wang 《PloS one》2013,8(11)
The objective of the current study was to determine the clinical significance of junctional adhesion molecule A (JAM-A) in patients with non-small cell lung cancer (NSCLC) and the biological function of JAM-A in NSCLC cell lines. We showed that JAM-A is predominantly expressed in cell membranes and high expression of JAM-A occurred in 37% of lung tumor specimens compared to corresponding normal tissues. High expression of JAM-A was significantly correlated with TNM stage (P = 0.021), lymph node metastasis (P = 0.007), and decreased overall survival (P = 0.02), In addition, we observed that silencing JAM-A by small interfering RNA inhibited tumor cell proliferation and induced cell cycle arrest at the G1/S boundary. Western blotting analysis revealed that knockdown of JAM-A decreased the protein levels of cyclin D1, CDK4, 6, and P-Rb. Thus, JAM-A plays an important role in NSCLC progression. 相似文献
943.
944.
Purpose
It remains controversial whether mini-incision (MI) benefits patients in total hip arthroplasty (THA). We performed a meta-analysis of randomized controlled trials (RCTs) to assess the effects of MI on surgical and functional outcomes in THA patients.Methods
A systematic electronic literature search (up to May 2013) was conducted to identify RCTs comparing MI with standard incision (SI) THA. The primary outcome measures were surgical and functional outcomes. According to the surgical approach taken, MI THA patients were divided into four subgroups for sub-group meta-analysis. Standardized mean differences (SMDs) or risk differences (RDs) with accompanying 95% confidence intervals (CIs) were calculated and pooled using a fixed-effect or random-effect model according to the heterogeneity.Results
A total of 14 RCTs involving THA 1,174 patients met the inclusion criteria. The trials were medium risk of bias. The overall meta-analysis showed MI THA reduced total blood loss (95% CI, -201.83 to -21.18; p=.02) and length of hospital stay ( 95% CI, -0.67 to -0.08; p=.01) with significant heterogeneity. However, subgroup meta-analysis revealed posterior MI THA had perioperative advantages of reduced surgical duration ( 95% CI, -8.45 to -2.67; P<.001), less blood loss ( 95% CI, -107.20 to -1.73; P=.04) and shorter hospital stay ( 95% CI, -0.74 to -0.06; p=.002) with low heterogeneity. There were no significant differences between MI and SI THA groups in term of pain medication dose, functional outcome (HHS), radiological outcome or complications (P>.05, respectively).Conclusions
Although no definite overall conclusion can be arrived at on whether MI THA is superior to SI THA, posterior MI THA clearly result in a significant decrease in surgical duration, blood loss and hospital stay. It seems to be a safe minimally invasive surgical procedure without increasing the risk of component malposition or complications. 相似文献945.
Objective
To determine the pathogenesis of a patient born with congenital heart defects, who had appeared normal in prenatal screening.Methods
In routine prenatal screening, G-banding was performed to analyse the karyotypes of the family and fluorescence in situ hybridization was used to investigate the 22q11.2 deletion in the fetus. After birth, the child was found to be suffering from heart defects by transthoracic echocardiography. In the following study, sequencing was used to search for potential mutations in pivotal genes. SNP-array was employed for fine mapping of the aberrant region and quantitative real-time PCR was used to confirm the results. Furthermore, other patients with a similar phenotype were screened for the same genetic variations. To compare with a control, these variations were also assessed in the general population.Results
The child and his mother each had a region that was deleted in the beta-defensin repeats, which are usually duplicated in the general population. Besides, the child carried a SOX7-gene duplication. While this duplication was not detected in his mother, it was found in two other patients with cardiac defects who also had the similar deletion in the beta-defensin repeats.Conclusion
The congenital heart defects of the child were probably caused by a SOX7-gene duplication, which may be a consequence of the partial haplotype of beta-defensin regions at 8p23.1. To our knowledge, this is the first congenital heart defect case found to have the haplotype of beta-defensin and the duplication of SOX7. 相似文献946.
Qing Tian Li Pei Xun Zhang Xiao Feng Yin Na Han Yu Hui Kou Jiu Xu Deng Bao Guo Jiang 《PloS one》2013,8(11)
Functional recovery is usually poor following peripheral nerve injury when reinnervation is delayed. Early innervation by sensory nerve has been indicated to prevent atrophy of the denervated muscle. It is hypothesized that early protection with sensory axons is adequate to improve functional recovery of skeletal muscle following prolonged denervation of mixed nerve injury. In this study, four groups of rats received surgical denervation of the tibial nerve. The proximal and distal stumps of the tibial nerve were ligated in all animals except for those in the immediate repair group. The experimental groups underwent denervation with nerve protection of peroneal nerve (mixed protection) or sural nerve (sensory protection). The experimental and unprotected groups had a stage II surgery in which the trimmed proximal and distal tibial nerve stumps were sutured together. After 3 months of recovery, electrophysiological, histological and morphometric parameters were assessed. It was detected that the significant muscle atrophy and a good preserved structure of the muscle were observed in the unprotected and protective experimental groups, respectively. Significantly fewer numbers of regenerated myelinated axons were observed in the sensory-protected group. Enhanced recovery in the mixed protection group was indicated by the results of the muscle contraction force tests, regenerated myelinated fiber, and the results of the histological analysis. Our results suggest that early axons protection by mixed nerve may complement sensory axons which are required for promoting functional recovery of the denervated muscle natively innervated by mixed nerve. 相似文献
947.
Zhengang Ma Chunfeng Li Guoqing Pan Zhihong Li Bing Han Jinshan Xu Xiqian Lan Jie Chen Donglin Yang Quanmei Chen Qi Sang Xiaocun Ji Tian Li Mengxian Long Zeyang Zhou 《PloS one》2013,8(12)
Microsporidia have attracted much attention because they infect a variety of species ranging from protists to mammals, including immunocompromised patients with AIDS or cancer. Aside from the study on Nosema ceranae, few works have focused on elucidating the mechanism in host response to microsporidia infection. Nosema bombycis is a pathogen of silkworm pébrine that causes great economic losses to the silkworm industry. Detailed understanding of the host (Bombyx mori) response to infection by N. bombycis is helpful for prevention of this disease. A genome-wide survey of the gene expression profile at 2, 4, 6 and 8 days post-infection by N. bombycis was performed and results showed that 64, 244, 1,328, 1,887 genes were induced, respectively. Up to 124 genes, which are involved in basal metabolism pathways, were modulated. Notably, B. mori genes that play a role in juvenile hormone synthesis and metabolism pathways were induced, suggesting that the host may accumulate JH as a response to infection. Interestingly, N. bombycis can inhibit the silkworm serine protease cascade melanization pathway in hemolymph, which may be due to the secretion of serpins in the microsporidia. N. bombycis also induced up-regulation of several cellular immune factors, in which CTL11 has been suggested to be involved in both spore recognition and immune signal transduction. Microarray and real-time PCR analysis indicated the activation of silkworm Toll and JAK/STAT pathways. The notable up-regulation of antimicrobial peptides, including gloverins, lebocins and moricins, strongly indicated that antimicrobial peptide defense mechanisms were triggered to resist the invasive microsporidia. An analysis of N. bombycis-specific response factors suggested their important roles in anti-microsporidia defense. Overall, this study primarily provides insight into the potential molecular mechanisms for the host-parasite interaction between B. mori and N. bombycis and may provide a foundation for further work on host-parasite interaction between insects and microsporidia. 相似文献
948.
949.
The objective of this study was to characterize the changes in lignin structure during hydrothermal pretreatment of shrub Tamarix ramosissima. Lignins in residual wood meal were isolated with alkaline ethanol solution and recovered with acid precipitation. A comparison between the recovered lignin fractions with milled wood lignin has been made in terms of yield, purity, gel permeation chromatography, Fourier transform infrared spectroscopy, pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), 1D 13C and 2D heteronuclear single quantum coherence nuclear magnetic resonance (HSQC NMR) spectroscopic techniques. Semiquantitative HSQC NMR showed that the relative amounts of β-O-4′ (around 76 % side chains) and resinol type substructures (16 %) of lignins were significantly modified during hydrothermal pretreatment. Py-GC/MS analyses brought direct evidences of these lignin samples with high S/G ratios ranging from 1.7 to 2.6. Moreover, the results indicated that an increase in the severity of the hydrothermal pretreatment enhanced the degradation of lignin unit side chains and the condensation of lignin and decreased the molecular weight of the recovered lignin fractions. This study demonstrated that the combination of autohydrolysis and alkaline ethanol process could potentially turn the recovered lignin fractions into value added products being in accordance with the “biorefinery” concept. 相似文献
950.
Xiaoyu Yang Wei Xu Svetlana Dukleska Sabrina Benchaar Selina Mengisen Valentyn Antochshuk Jason Cheung Leslie Mann Zulfia Babadjanova Jason Rowand Rico Gunawan Alexander McCampbell Maribel Beaumont David Meininger Daisy Richardson Alexandre Ambrogelly 《MABS-AUSTIN》2013,5(5):787-794
Monoclonal antibodies constitute a robust class of therapeutic proteins. Their stability, resistance to stress conditions and high solubility have allowed the successful development and commercialization of over 40 antibody-based drugs. Although mAbs enjoy a relatively high probability of success compared with other therapeutic proteins, examples of projects that are suspended due to the instability of the molecule are not uncommon. Developability assessment studies have therefore been devised to identify early during process development problems associated with stability, solubility that is insufficient to meet expected dosing or sensitivity to stress. This set of experiments includes short-term stability studies at 2−8 þC, 25 þC and 40 þC, freeze-thaw studies, limited forced degradation studies and determination of the viscosity of high concentration samples. We present here three case studies reflecting three typical outcomes: (1) no major or unexpected degradation is found and the study results are used to inform early identification of degradation pathways and potential critical quality attributes within the Quality by Design framework defined by US Food and Drug Administration guidance documents; (2) identification of specific degradation pathway(s) that do not affect potency of the molecule, with subsequent definition of proper process control and formulation strategies; and (3) identification of degradation that affects potency, resulting in program termination and reallocation of resources. 相似文献