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991.
Mycophenolate Mofetil and Rapamycin Induce Apoptosis in the Human Monocytic U937 Cell Line Through Two Different Pathways
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992.
Martin J. Westgate Ayesha I. T. Tulloch Philip S. Barton Jennifer C. Pierson David B. Lindenmayer 《Ecography》2017,40(4):539-548
A fundamental decision in biodiversity assessment is the selection of one or more study taxa, a choice that is often made using qualitative criteria such as historical precedent, ease of detection, or available technical or taxonomic expertise. A more robust approach would involve selecting taxa based on the a priori expectation that they will provide the best possible information on unmeasured groups, but data to inform such hypotheses are often lacking. Using a global meta‐analysis, we quantified the proportion of variability that each of 12 taxonomic groups (at the Order level or above) explained in the richness or composition of other taxa. We then applied optimization to matrices of pairwise congruency to identify the best set of complementary surrogate groups. We found that no single taxon was an optimal surrogate for both the richness and composition of unmeasured taxa if we used simple methods to aggregate congruence data between studies. In contrast, statistical methods that accounted for well‐known drivers of cross‐taxon congruence (spatial extent, grain size, and latitude) lead to the prioritization of similar surrogates for both species richness and composition. Advanced statistical methods were also more effective at describing known ecological relationships between taxa than simple methods, and show that congruence is typically highest between taxonomically and functionally dissimilar taxa. Birds and vascular plants were most frequently selected by our algorithm as surrogates for other taxonomic groups, but the extent to which any one taxon was the ‘optimal’ choice of surrogate for other biodiversity was highly context‐dependent. In the absence of other information – such as in data‐poor areas of the globe, and under limited budgets for monitoring or assessment – ecologists can use our results to assess which taxa are most likely to reflect the distribution of the richness or composition of ‘total’ biodiversity. 相似文献
993.
Exploiting cell cycle inhibitor genes of the KRP family to control root‐knot nematode induced feeding sites in plants
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José Dijair Antonino de Souza Júnior Cristina Martin‐Jimenez Lieven De Veylder Julie Cazareth Gilbert Engler Maria Fatima Grossi‐de‐Sa Janice de Almeida Engler 《Plant, cell & environment》2017,40(7):1174-1188
Cell cycle control in galls provoked by root‐knot nematodes involves the activity of inhibitor genes like the Arabidopsis ICK/KRP members. Ectopic KRP1, KRP2 and KRP4 expression resulted in decreased gall size by inhibiting mitotic activity, whereas KRP6 induces mitosis in galls. Herein, we investigate the role of KRP3, KRP5 and KRP7 during gall development and compared their role with previously studied members of this class of cell cycle inhibitors. Overexpression of KRP3 and KRP7 culminated in undersized giant cells, with KRP3OE galls presenting peculiar elongated giant cells. Nuclei in KRP3OE and KRP5OE lines presented a convoluted and apparently connected phenotype. This appearance may be associated with the punctuated protein nuclear localization driven by specific common motifs. As well, ectopic expression of KRP3OE and KRP5OE affected nematode development and offspring. Decreased mitotic activity in galls of KRP3OE and KRP7OE lines led to a reduced gall size which presented distinct shapes – from more elongated like in the KRP3OE line to small rounded like in the KRP7OE line. Results presented strongly support the idea that induced expression of cell cycle inhibitors such as KRP3 and KRP7 in galls can be envisaged as a conceivable strategy for nematode feeding site control in crop species attacked by phytopathogenic nematodes. 相似文献
994.
A TRPV1‐to‐secretagogin regulatory axis controls pancreatic β‐cell survival by modulating protein turnover
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Katarzyna Malenczyk Fatima Girach Edit Szodorai Petter Storm Åsa Segerstolpe Giuseppe Tortoriello Robert Schnell Jan Mulder Roman A Romanov Erzsébet Borók Fabiana Piscitelli Vincenzo Di Marzo Gábor Szabó Rickard Sandberg Stefan Kubicek Gert Lubec Tomas Hökfelt Ludwig Wagner Leif Groop Tibor Harkany 《The EMBO journal》2017,36(14):2107-2125
995.
996.
Lívia Gelain Castilhos Juliana Sorraila de Oliveira Stephen Adeniyi Adefegha Luana Pereira Magni Pedro Henrique Doleski Fatima Husein Abdalla 《Redox report : communications in free radical research》2017,22(6):451-459
Objectives: This study was conducted to assess the markers of oxidative stress, myeloperoxidase (MPO), acetylcholinesterase (AChE) and xanthine oxidase (XO) activities as well as the levels of nucleotide metabolites in sickle cell anemia (SCA) patients.Methods: Fifteen SCA treated patients and 30 health subjects (control group) were selected. The markers of oxidative stress (levels of reactive oxygen species (ROS), plasma proteins, carbonyl content, lipid peroxidation (TBARS), total thiols (T-SH), glutathione and catalase activity), MPO, AChE and XO activities as well as the levels of nucleotide metabolites were measured in SCA patients.Results: ROS, thiobarbituric acid-reactive substances (TBARS) and T-SH levels as well as the activities of catalase and MPO were significantly increased while glutathione level was reduced in SCA patients. Furthermore, a significant (P?0.001) increase in hypoxanthine level was demonstrated in SCA patients. However, the serum levels for xanthine (P?0.01) and uric acid (P?0.001) were decreased in SCA patients. A significant (P?0.001) decrease in XO activity was detected in SCA patients.Discussion: The altered parameters in SCA patients suggest that the generation and impairment of oxidative stress in this disease as well as antioxidant markers are contributory factors towards cellular redox homeostasis and alteration of purine metabolites. 相似文献
997.
Matthew D. Martens Nivedita Seshadri Lucas Nguyen Donald Chapman Elizabeth S. Henson Bo Xiang Landon Falk Arielys Mendoza Sunil Rattan Jared T. Field Philip Kawalec Spencer B. Gibson Richard Keijzer Ayesha Saleem Grant M. Hatch Christine A. Doucette Jason M. Karch Vernon W. Dolinsky Ian M. Dixon Adrian R. West Christof Rampitsch Joseph W. Gordon 《Cell death & disease》2021,12(12)
Systemic hypoxia is a common element in most perinatal emergencies and is a known driver of Bnip3 expression in the neonatal heart. Bnip3 plays a prominent role in the evolution of necrotic cell death, disrupting ER calcium homeostasis and initiating mitochondrial permeability transition (MPT). Emerging evidence suggests a cardioprotective role for the prostaglandin E1 analog misoprostol during periods of hypoxia, but the mechanisms for this protection are not completely understood. Using a combination of mouse and cell models, we tested if misoprostol is cardioprotective during neonatal hypoxic injury by altering Bnip3 function. Here we report that hypoxia elicits mitochondrial-fragmentation, MPT, reduced ejection fraction, and evidence of necroinflammation, which were abrogated with misoprostol treatment or Bnip3 knockout. Through molecular studies we show that misoprostol leads to PKA-dependent Bnip3 phosphorylation at threonine-181, and subsequent redistribution of Bnip3 from mitochondrial Opa1 and the ER through an interaction with 14-3-3 proteins. Taken together, our results demonstrate a role for Bnip3 phosphorylation in the regulation of cardiomyocyte contractile/metabolic dysfunction, and necroinflammation. Furthermore, we identify a potential pharmacological mechanism to prevent neonatal hypoxic injury.Subject terms: Cell death, Cardiovascular biology 相似文献
998.
Shuhui Song Cuiping Li Lu Kang Dongmei Tian Nazish Badar Wentai Ma Shilei Zhao Xuan Jiang Chun Wang Yongqiao Sun Wenjie Li Meng Lei Shuangli Li Qiuhui Qi Aamer Ikram Muhammad Salman Massab Umair Huma Shireen Fatima Batool Bing Zhang Hua Chen Yun-Gui Yang Amir Ali Abbasi Mingkun Li Yongbiao Xue Yiming Bao 《基因组蛋白质组与生物信息学报(英文版)》2021,19(5):727-740
COVID-19 has swept globally and Pakistan is no exception. To investigate the initial introductions and transmissions of the SARS-CoV-2 in Pakistan, we performed the largest genomic epidemiology study of COVID-19 in Pakistan and generated 150 complete SARS-CoV-2 genome sequences from samples collected from March 16 to June 1, 2020. We identified a total of 347 mutated positions, 31 of which were over-represented in Pakistan. Meanwhile, we found over 1000 intra-host single-nucleotide variants (iSNVs). Several of them occurred concurrently, indicating possible interactions among them or coevolution. Some of the high-frequency iSNVs in Pakistan were not observed in the global population, suggesting strong purifying selections. The genomic epidemiology revealed five distinctive spreading clusters. The largest cluster consisted of 74 viruses which were derived from different geographic locations of Pakistan and formed a deep hierarchical structure, indicating an extensive and persistent nation-wide transmission of the virus that was probably attributed to a signature mutation (G8371T in ORF1ab) of this cluster. Furthermore, 28 putative international introductions were identified, several of which are consistent with the epidemiological investigations. In all, this study has inferred the possible pathways of introductions and transmissions of SARS-CoV-2 in Pakistan, which could aid ongoing and future viral surveillance and COVID-19 control. 相似文献
999.
1000.