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81.
Yanqing Huang Tomoaki Hamana Junchen Liu Cong Wang Lei An Pan You Julia Y. F. Chang Jianming Xu Wallace L. McKeehan Fen Wang 《The Journal of biological chemistry》2015,290(29):17745-17752
Prostate stem cells (P-SCs) are capable of giving rise to all three lineages of prostate epithelial cells, including basal, luminal, and neuroendocrine cells. Multiple methods have been used to identify P-SCs in adult prostates. These include in vivo renal capsule implantation of a single epithelial cell with urogenital mesenchymal cells, in vitro prostasphere and organoid cultures, and lineage tracing with castration-resistant Nkx3.1 expression (CARN), in conjunction with expression of cell type-specific markers. Both organoid culture and CARN tracing show the existence of P-SCs in the luminal compartment. Although prostasphere cells predominantly express basal cell-specific cytokeratin and P63, the lineage of prostasphere-forming cells in the P-SC hierarchy remains to be determined. Using lineage tracing with P63CreERT2, we show here that the sphere-forming P-SCs are P63-expressing cells and reside in the basal compartment. Therefore we designate them as basal P-SCs (P-bSCs). P-bSCs are capable of differentiating into AR+ and CK18+ organoid cells, but organoid cells cannot form spheres. We also report that prostaspheres contain quiescent stem cells. Therefore, the results show that P-bSCs represent stem cells that are early in the hierarchy of overall prostate tissue stem cells. Understanding the contribution of the two types of P-SCs to prostate development and prostate cancer stem cells and how to manipulate them may open new avenues for control of prostate cancer progression and relapse. 相似文献
82.
本研究探讨利用荧光定量PCR技术评价Sindbis病毒经亚甲蓝光化学处理后灭活效果的可行性。研究采用不同光照强度对Sindbis病毒进行亚甲蓝光化学灭活处理,并用SYBR Green I荧光定量PCR对Sindbis病毒的cDNA进行扩增,同时以细胞病变法做平行对照以测定病毒残余滴度。结果显示在亚甲蓝光化学处理过程中,随着光照强度的增强,病毒残余滴度由6.50 LgTCID50/mL逐渐降低至检测限以下,同时病毒核酸的拷贝数显著下降(P<0.05),并与病毒感染性的降低呈线性相关(R2>0.98)。以上结果表明,亚甲蓝光化学灭活法对Sindbis病毒核酸有破坏作用,病毒核酸损伤程度随光照强度的增强而增加,且与病毒感染性的降低存在相关性,提示荧光定量PCR技术评价亚甲蓝光化学法的病毒灭活效果具有可行性。 相似文献
83.
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85.
Fen Liu Yi-Ning Yang Xiang Xie Xiao-Mei Li Xiang Ma Zhen-Yan Fu Bang-Dang Chen Ying Huang Chun-Fang Shan Yi-Tong Ma Xiao-Ming Gao 《PloS one》2015,10(8)
Background
The prevalence and risk factors of congenital heart disease among Xinjiang, northwestern part of China is currently unknown.Methods
This multiple-ethnic, community-based, cross-sectional study was conducted to estimate the prevalence and distribution of congenital heart disease (CHD) in Xinjiang, northwestern part of China. Four major ethnics, Uygur, Han, Kazak, and Hui children in this region were investigated during February 2010 and May 2012.Results
A total of 14,530 children (0–18 yr) were examined. Of these children, 240 (boys, 43.8%, and girls, 56.3%) were identified with CHD, giving an overall prevalence of 16.5‰ (17.7‰ in Uygur, 6.9‰ in Han, 11.4‰ in Kazak, and 38.1‰ in Hui Chinese, respectively). Ventricular septal defect (VSD, 29.2%), atrial septal defect (ASD, 20.8%), patent ductus arteriosus (PDA, 13.7%), acleistocardia (13.7%), Bicuspid aortic valve (7.9%), pulmonary valve stenosis (5.4%), and tetralogy of fallot (TOF, 4.2%) were common cyanotic and cyanotic defects observed. Compared to non-CHD children, children with CHD had a higher percentage of history of abortion, CHD history of family, consanguinity and premature birth (all P<0.05). In CHD children, 24% of mothers caught a cold, 10% had a febrile illness and 6.7% received antibiotic treatment during the first trimester of pregnancy, that were higher than non-CHD group (all P<0.05).Conclusion
The overall prevalence of CHD in four ethnic children at ages 0–18 yr in Xinjiang was 16.5‰. VSD, ASD and TOF were the most common acyanotic and cyanotic congenital heart defects, respectively. This study also identified some modifiable risk factors that may contribute to the incidence of CHD among the 4 ethnic groups. 相似文献86.
Amino Acids - Autophagy plays an important role in biological evolution and is regulated by many autophagy proteins. Accurate identification of autophagy proteins is crucially important to reveal... 相似文献
87.
Yi-Qing Gong Qing-Qing Zhan Khang Sinh Nguyen Hiep Tien Nguyen Yue-Hua Wang Xun Gong 《PloS one》2015,10(2)
Cycas multipinnata C.J. Chen & S.Y. Yang is a cycad endemic to the Red River drainage region that occurs under evergreen forest on steep limestone slopes in Southwest China and northern Vietnam. It is listed as endangered due to habitat loss and over-collecting for the ornamental plant trade, and only several populations remain. In this study, we assess the genetic variation, population structure, and phylogeography of C. multipinnata populations to help develop strategies for the conservation of the species. 60 individuals from six populations were used for chloroplast DNA (cpDNA) sequencing and 100 individuals from five populations were genotyped using 17 nuclear microsatellites. High genetic differentiation among populations was detected, suggesting that pollen or seed dispersal was restricted within populations. Two main genetic clusters were observed in both the cpDNA and microsatellite loci, corresponding to Yunnan China and northern Vietnam. These clusters indicated low levels of gene flow between the regions since their divergence in the late Pleistocene, which was inferred from both Bayesian and coalescent analysis. In addition, the result of a Bayesian skyline plot based on cpDNA portrayed a long history of constant population size followed by a decline in the last 50,000 years of C. multipinnata that was perhaps affected by the Quaternary glaciations, a finding that was also supported by the Garza-Williamson index calculated from the microsatellite data. The genetic consequences produced by climatic oscillations and anthropogenic disturbances are considered key pressures on C. multipinnata. To establish a conservation management plan, each population of C. multipinnata should be recognized as a Management Unit (MU). In situ and ex situ actions, such as controlling overexploitation and creating a germplasm bank with high genetic diversity, should be urgently implemented to preserve this species. 相似文献
88.
为了探讨绿木霉与褐环乳牛肝菌的互作机理,在体外共培养条件下,采用光学显微镜和扫描电镜对二者生长重叠部分进行体外观察,发现二者生长无相互影响,在营养生长方面几乎不存在竞争关系。为进一步揭示绿木霉与褐环乳牛肝菌的互作机制,采用体外诱导和生物化学等方法,向褐环乳牛肝菌发酵液中加入灭活绿木霉菌丝诱导物,每天对发酵液中的多酚氧化酶、几丁质酶、漆酶和中性蛋白酶等酶活性进行检测。试验结果表明,绿木霉诱导褐环乳牛肝菌产漆酶能力最强;在整个共培养过程中,多酚氧化酶和漆酶活力始终处于较高水平,在诱导培养第6天,这两种酶活性升至最高,分别达到25.2U/mL和1 580U/mL;灭活绿木霉菌丝对褐环乳牛肝菌几丁质酶的诱导具有“瞬时性”,在诱导培养第2天即检测到较高的几丁质酶活性;中性蛋白酶的活性变化基本上呈先上升后下降的规律,且能增大褐环乳牛肝菌中性蛋白酶的固有产量,形成“叠加效果”。综上所述,绿木霉对褐环乳牛肝菌几乎不存在营养竞争关系,但其灭活菌丝体对褐环乳牛肝菌发酵液的多种酶活性存在诱导增效作用。 相似文献
89.
Cloning and Functional Expression of a Novel Geranylgeranyl Pyrophosphate Synthase Gene from Arabidopsis thaliana in Escherichia coli 总被引:1,自引:0,他引:1
Zhu Fen; Suzuki Kengo; Okada Kazunori; Tanaka Katsunori; Nakagawa Tsuyoshi; Kawamukai Makoto; Matsuda Hideyuki 《Plant & cell physiology》1997,38(3):357-361
A gene encoding a novel geranylgeranyl pyrophosphate (GGPP)synthase from Arabidopsis thaliana has been identified and termedGGPS5. The gene has been sequenced and expressed in Escherichiacoli. The deduced amino acid sequence showed 64.5% and 57.5%identity with a putative GGPP synthase from Arabidopsis andCapsicum annuum, respectively. GGPP enzymatic activity was detectedin E. coli cells expressing the GGPS5 gene in two differentways. One was the direct measurement of GGPP synthase activityin cell extracts and the other was the yellow color productionof cells when the GGPS5 gene was co-expressed with crtB, crtI,crtX, crtY and crtZ genes derived from Erwinia uredovora. (Received May 20, 1996; Accepted December 14, 1996) 相似文献
90.
Jasmonates are a new class of plant hormones that play important roles in plant development and plant defense. TheCOI1 gene was previously shown to be required for jasmonate-regulated plant fertility and defense. We demonstrated for the first
time that COI1 interacts with theArabidopsis SKP1-LIKE1 (ASK1) to form a complex that is required for jasmonate action inplanta. Functional analysis by antisense strategy showed thatASK1 is involved in male fertility. 相似文献