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991.
从紫果西番莲(Pasifloraedulis)、杂交种西番莲(P.edulisXP.edulisvar.flavicarpa)、黄果西番莲(P.edulisvar.flavicarpa)、转心莲(P.caerulea)及龙珠果(P.foetida)分离到的5个黄瓜花叶病毒(CMV)分离物(PE、PE2、PEf、PC、PF)所作的生物学性质、理化特性和血清学关系的比较研究结果表明,5个分离物在寄主反应及血清学性质上存在不同,而在病毒粒体形态、体外抗性、蚜虫传毒和病毒外壳蛋白分子量方面无明显差异。根据5个分离物的寄主反应和血清学关系,可将其区分为CMV的两个亚组,其中PE、PE2、PC和PF属CMV亚组I,PEf属CMV亚组I。 相似文献
992.
993.
Qian Wang Jin Liu Josephine M Janssen Francesca Tasca Hailiang Mei Manuel A F V Gonalves 《Nucleic acids research》2021,49(20):11986
Prime editing is a recent precision genome editing modality whose versatility offers the prospect for a wide range of applications, including the development of targeted genetic therapies. Yet, an outstanding bottleneck for its optimization and use concerns the difficulty in delivering large prime editing complexes into cells. Here, we demonstrate that packaging prime editing constructs in adenoviral capsids overcomes this constrain resulting in robust genome editing in both transformed and non-transformed human cells with up to 90% efficiencies. Using this cell cycle-independent delivery platform, we found a direct correlation between prime editing activity and cellular replication and disclose that the proportions between accurate prime editing events and unwanted byproducts can be influenced by the target-cell context. Hence, adenovector particles permit the efficacious delivery and testing of prime editing reagents in human cells independently of their transformation and replication statuses. The herein integrated gene delivery and gene editing technologies are expected to aid investigating the potential and limitations of prime editing in numerous experimental settings and, eventually, in ex vivo or in vivo therapeutic contexts. 相似文献
994.
Xibao Wang Shengyang Zhou Xiaoyang Wu Qinguo Wei Yongquan Shang Guolei Sun Xuesong Mei Yuehuan Dong Weilai Sha Honghai Zhang 《Ecology and evolution》2021,11(21):15077
The high‐altitude environment may drive vertebrate evolution in a certain way, and vertebrates living in different altitude environments might have different energy requirements. We hypothesized that the high‐altitude environment might impose different influences on vertebrate mitochondrial genomes (mtDNA). We used selection pressure analyses and PIC (phylogenetic independent contrasts) analysis to detect the evolutionary rate of vertebrate mtDNA protein‐coding genes (PCGs) from different altitudes. The results showed that the ratio of nonsynonymous/synonymous substitutions (dN/dS) in the mtDNA PCGs was significantly higher in high‐altitude vertebrates than in low‐altitude vertebrates. The seven rapidly evolving genes were shared by the high‐altitude vertebrates, and only one positive selection gene (ND5 gene) was detected in the high‐altitude vertebrates. Our results suggest the mtDNA evolutionary rate in high‐altitude vertebrates was higher than in low‐altitude vertebrates as their evolution requires more energy in a high‐altitude environment. Our study demonstrates the high‐altitude environment (low atmospheric O2 levels) drives vertebrate evolution in mtDNA PCGs. 相似文献
995.
Associations of the PTEN − 9C>G polymorphism with insulin sensitivity and central obesity in Chinese
Qiu Yang Hongyi Cao Shugui Xie Yuzhen Tong Qibo Zhu Fang Zhang Qingguo Lü Yan Yang Daigang Li Mei Chen Changyong Yu Wei Jin Yuquan Yuan Nanwei Tong 《Gene》2013
Background
Phosphatase and tensin homolog on chromosome 10 gene (PTEN) is known as a tumor-suppressor gene. Previous studies demonstrated that PTEN dysfunction affects the function of insulin. However, investigations of PTEN single nucleotide polymorphisms (SNPs) and IR-related disease associations are limited. The aim of the present study was to investigate whether its polymorphism could be involved in the risk of metabolic syndrome (MetS).Methods
The genotype frequency of PTEN − 9C>G polymorphism was determined by using a Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) method in 530 subjects with MetS and 202 healthy control subjects of the Han Ethnic Chinese population in a case–control analysis.Results
The PTEN − 9C>G polymorphism was not associated with MetS or its hyperglycemia, hypertension and hypertriglyceridemia components. In the control individuals aged < 60 years or ≥ 60 years, the CG genotype individuals had lower insulin sensitivity than CC individuals (P < 0.05). In the < 60-year-old MetS group and normal glucose tolerance (NGT) subgroup, the CG individuals had lower insulin sensitivity and higher waist circumference (WC) and waist-height-ratio (WHtR) than CC individuals (P < 0.05). Multiple linear regression analysis showed that the PTEN polymorphism (P = 0.001) contributed independently to 4.2% (adjusted R2) of insulin sensitivity variance (estimated by Matsuda ISI), while age (P = 0.004), gender (P = 0.000) and the PTEN polymorphism (P = 0.032) contributed independently to 5.6% (adjusted R2) of WHtR variance.Conclusions
The CG genotype of PTEN − 9C>G polymorphism was not associated with MetS and some of its components as well. However, it may not only decrease insulin sensitivity in the healthy control and MetS in pre-elderly or NGT subjects, but may also increase the risk of central obesity among these MetS individuals. 相似文献996.
Yaoyao Zhang Xiaodong Sun Zhiwen Nong Mo Chen Yujiang Hao Jianghua Wang Kexiong Wang Ding Wang Zhigang Mei 《Marine Mammal Science》2024,40(2):e13082
The establishment of marine protected areas (MPAs) for cetaceans is an important strategy to mitigate human disturbance and protect biodiversity. Despite abundant cetacean species, there are only a few MPAs dedicated to cetacean conservation in China, all of which are for inshore dolphins. Bryde's whales, the only nearshore baleen whale population in mainland China, are conflicting with intensive human activities, yet an effective conservation strategy is lacking. This study used species distribution models to analyze distribution patterns and suitable habitats of Bryde's whales in the Beibu Gulf and proposes the first baleen whale MPA in China. Our results showed Bryde's whales have a seasonal distribution pattern in the Beibu Gulf, and that the waters around Weizhou Island and the southeastern coast of Vietnam were their core habitats. The seasonal nighttime light data indicated a negative relationship between the number of ship lights and Bryde's whale sightings and suggest that Bryde's whales might be threatened by fisheries. We proposed an MPA based on the results, suggesting that the waters within 20 km around Weizhou Island should be declared a protected area. Furthermore, we recommend that anthropogenic activities in the waters around Weizhou Island are better managed to reduce negative impacts on marine life. 相似文献
997.
【背景】近年来,炎症性肠病患者中艰难梭菌(Clostridium difficile)感染率逐年上升,受到国内外学者广泛关注。我国在该领域的研究起步较晚,但患者数量众多,学习国际上对于炎症性肠病合并艰难梭菌感染的研究,对推动我国在该领域的深入发展具有重要意义。【目的】通过文献计量和可视化分析帮助研究者把握炎症性肠病与艰难梭菌感染相关性研究中的研究主题、方向、热点与前沿。【方法】同时检索Web of Science (WOS)中Science Citation Index Expanded (SCI-E)和CNKI中收录的关于炎症性肠病和艰难梭菌的相关文献,应用CiteSpace 6.2.2r软件进行国家/地区、机构、作者、关键词共现及被引文献、期刊共被引分析,同时进行可视化分析。【结果】经过数据检索和查重,最终可供分析的文献为WOS数据库1 030篇、CNKI数据库80篇。全球范围内,发文最多的国家是美国,主要研究机构有Harvard University、University of California System和Mayo Clinic等,高产作者有Khanna S、Shen B和Ananthakrishnan AN等,高频关键词包括Inflammatory bowel disease、Ulcerative colitis、Clostridium difficile、Clostridium difficile infection和Crohn’s disease等,聚类方向有#0 Diarrhea、#1 Ulcerative colitis、#2 Probiotics、#3 Pouchitis、#4 Gut microbiota、#5 Fecal microbiota transplantation、#6 Depression、#7 Entamoeba histolytica、#8 Pseudomembranous colitis、#9 Clostridium difficile和#10 Clindamycin。国内主要研究机构有南方医科大学和河北医科大学,高产作者有王浦、王斯淇等,高频关键词包括粪菌移植、艰难梭菌、肠道菌群、危险因素和克罗恩病等,聚类方向有#0艰难梭菌、#1益生菌、#2危险因素、#3腹泻和#4粪菌移植。【结论】利用CiteSpace软件对炎症性肠病和艰难梭菌感染相关性研究进行计量及可视化分析可知,该方向仍得到全球各医疗机构及研究者的关注,腹泻及粪菌移植这两个关键词分别代表了WOS数据库和CNKI数据库关于炎症性肠病合并艰难梭菌感染研究的热点。 相似文献
998.
999.
Jiahn‐Chun Wu Tun‐Hui Chung Yung‐Zu Tseng Seu‐Mei Wang 《Journal of cellular biochemistry》1999,75(1):93-104
N‐cadherin is a member of the Ca2+‐dependent cell adhesion molecules and plays an important role in the assembly of the adherens junction in chicken cardiomyocytes. In addition to being present at the cell‐cell junction, N‐cadherin is associated with costameres in extrajunctional regions. The significance of the N‐cadherin‐associated costameres and whether catenins are components of costameres in chicken cardiomyocytes are not known. In this study, double‐labeling immunofluorescence microscopy was used to determine the extrajunctional distribution of both N‐cadherin and its cytoplasmic associated proteins, α‐ and β‐catenins, and their relationship to myofibrillar Z‐disc α‐actinin. N‐cadherin, α‐, and β‐catenins were all found to be present at the extrajunctional region and, in some cases, were codistributed with myofibrillar α‐actinin exhibiting a periodic staining pattern. Confocal microscopy confirmed that both N‐cadherin and β‐catenin colocalized with peripheral myofibrillar α‐actinin on the dorsal surface of cardiomyocytes as components of the costameres. Intracellular application of antibodies specific for the cytoplasmic portions of N‐cadherin, α‐, and β‐catenin, either by electroporation or microinjection, resulted in myofibril disorganization and disassembly. These results suggest the existence of N‐cadherin/catenin‐based costameres in the dorsal surface of cultured chicken cardiomyocytes in addition to the integrin/vinculin‐based costameres found in the ventral surface and indicate that the former set of costameres is essential for cardiac myofibrillogenesis. J. Cell. Biochem. 75:93–104, 1999. © 1999 Wiley‐Liss, Inc. 相似文献
1000.
Dapu Liu Zhikun Yu Guoxia Zhang Wenchao Yin Lulu Li Mei Niu Wenjing Meng Xiaoxing Zhang Nana Dong Jihong Liu Yanzhao Yang Shimei Wang Chengcai Chu Hongning Tong 《Plant physiology》2021,187(4):2563
Brassinosteroids (BRs) regulate various agronomic traits such as plant height, leaf angle, and grain size in rice (Oryza sativa L.); thus, BR signaling components are promising targets for molecular rational design. However, genetic materials for BR-signaling genes or family members remain limited in rice. Here, by genome editing using clustered regularly interspaced short palindromic repeats (CRSPR)/Cas9 tools, we generated a panel of single, double, triple, or quadruple mutants within three BR signaling gene families, including GSK3/SHAGGY-LIKE KINASE1 (GSK1)–GSK4, BRASSINAZOLE-RESISTANT1 (OsBZR1)–OsBZR4, and protein phosphatases with kelch-like (PPKL)1–PPKL3, under the same background (Zhonghua11, japonica). The high-order mutants were produced by either simultaneously targeting multiple sites on different genes of one family (GSKs and PPKLs) or targeting the overlapping sequences of family members (OsBZRs). The mutants exhibited a diversity of plant height, leaf angle, and grain morphology. Comparison analysis of the phenotypes together with BR sensitivity tests suggested the existence of functional redundancy, differentiation, or dominancy among the members within each family. In addition, we generated a set of transgenic plants overexpressing GSK2, OsBZR1/2, and PPKL2, respectively, in wild-type or activated forms with fusion of different tags, and also verified the protein response to BR application. Collectively, these plants greatly enriched the diversity of important agronomic traits in rice. We propose that editing of BR-related family genes could be a feasible approach for screening of desired plants to meet different requirements. Release of these materials as well as the related information also provides valuable resources for further BR research and utilization. 相似文献