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991.
Effect of salt stress on photosynthesis and physiological parameters of three contrasting barley genotypes 总被引:1,自引:0,他引:1
M. Mahlooji R. Seyed Sharifi J. Razmjoo M. R. Sabzalian M. Sedghi 《Photosynthetica》2018,56(2):549-556
In order to understand the physiological traits important in conferring salt tolerance in three barley genotypes, this study was performed under field conditions with three water salinity levels (2, 10, and 18 dS m–1). High salinity decreased net photosynthetic rate, transpiration rate, and stomatal conductance, K+ concentration, K+:Na+ ratio, and grain yield, but increased electrolyte leakage and Na+ content. Under 10 and 18 dS m–1 salinity, Khatam (salt-tolerant) had the maximum stomatal conductance, K+, K+:Na+ ratio, and the grain yield, and a minimum Na+ content and electrolyte leakage, whereas Morocco (salt-sensitive) had the lowest net photosynthetic rate, stomatal conductance, K+ content, K+:Na+ ratio, and grain yield, and the highest Na+ content and electrolyte leakage. This study showed that tolerant genotypes of barley may avoid Na+ accumulation in aboveground parts, facilitating a higher photosynthetic rate and higher grain yield. 相似文献
992.
Maryam Moradi-Chaleshtori Seyed Mahmoud Hashemi Sara Soudi Mojgan Bandehpour Samira Mohammadi-Yeganeh 《Journal of cellular physiology》2019,234(6):7970-7982
Tumor cells are able to modify their surrounding microenvironment by transmitting bioactive molecules via exosomes. In exosomes, proteins and nucleic acids that can be taken up by surrounding cells have been identified and modulate their functions. Tumor microenvironment consists of different cells such as macrophages. Tumors-associated macrophages (TAMs) express M2 phenotype and affect many processes including tumor initiation, angiogenesis, and metastasis. It has been demonstrated that a high number of TAMs is associated with poor prognosis of cancers. The contents of tumor-derived exosomes such as microRNAs and proteins induce macrophages to M2-like polarization to support tumor growth. Herein, we review the most recent studies on the effect of tumor-derived exosomes on macrophage polarization and function in different types of cancers. 相似文献
993.
Dorna Saadat Ali Asghar Seraj Seyed Hossein Goldansaz Javad Karimzadeh 《BioControl》2014,59(3):297-306
The biological control programs supporting the native species of natural enemies are far more sustainable than those which use exotic enemies of the target pest. Little is known about the effects of the surrounding environment on host selection behavior of Bracon hebetor Say (Hymenoptera: Braconidae). In the present study, the effects of the origin of the parasitoid populations, host species and parasitoid rearing history on host selection and parasitism success of B. hebetor were investigated. Several life-history parameters, including the frequency of parasitism, percentage parasitism, egg load, survival rate and the offspring sex ratio of the parasitoid were measured. In terms of both selection and parasitism success, B. hebetor preferred Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) over Apomyelois ceratoniae Zeller (Lepidoptera: Pyralidae) and Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), and A. ceratoniae over H. armigera. When different populations of B. hebetor were compared, the B. hebetor population originated from orchard was the most successful compared with the field and store populations. In addition, the rearing history was influential on the parasitism preference and success: a better performance of the parasitoid was obtained when it was reared on its original host compared with an intermediate host, E. kuehniella. The causes and consequences of these findings were further discussed in relation with mass rearing of this parasitoid for biological control programs. 相似文献
994.
Fatemeh Araste Walead Ebrahimizadeh Iraj Rasooli Masoumeh Rajabibazl Seyed Latif Mousavi Gargari 《Biotechnology letters》2014,36(1):21-28
Expression of carbonic anhydrase IX (CAIX) significantly increases under hypoxic conditions in tumor cells. CAIX activity is executed by the catalytic domain (CA) located on the extracellular part of the enzyme. Neutralization of CAIX enzymatic activity reduces malignancy and survival of tumor cells. To inhibit the enzymatic activity, a VHH nanobody was developed against the CA domain of CAIX using phage display technology. Following immunization of a camel with the recombinant CAIX, VHH fragments were isolated by nested PCR on lymphocyte cDNA. Binding affinity of isolated nanobodies was tested by ELISA. A clone (K24) with the highest binding affinity was expressed in a soluble form. Affinity of K24 nanobody was determined to be approx. 2.3 × 10?5. K24 nanobody recognized the expressed CAIX in the HeLa cell lines with high selectivity and specificity. These findings thus have usefulness for the diagnosis and treatment of cancers. 相似文献
995.
Iranian chicken genetic resources are characterized by a long history and a vast diversity. This study represents the first
results from the selection and evaluation of five polymorphic microsatellite markers for the genetic assessment of five native
chicken populations located in the northwestern (West Azerbaijan), northern (Mazandaran), central (Isfahan, Yazd), and southern
(Fars) provinces of Iran. The number of alleles ranged from three to six per microsatellite locus. All populations were characterized
by a high degree of genetic diversity, with the lowest heterozygosity found in the Isfahan population (62%) and the greatest
in the populations from West Azerbaijan and Mazandaran (79%). The largest Nei’s unbiased genetic distance was found between
the Isfahan and Fars populations (0.696) and the smallest between the Mazandaran and Yazd populations (0.097). The Isfahan
population was found to be the most genetically distant among all populations studied. These results serve as an initial step
in the plan for genetic characterization and conservation of Iranian native chickens. 相似文献
996.
Ultrasensitive DNA sensor based on gold nanoparticles/reduced graphene oxide/glassy carbon electrode
Ali Benvidi Afsaneh Dehghani Firouzabadi Seyed Mohammad Moshtaghiun Mohammad Mazloum-Ardakani Marzieh Dehghan Tezerjani 《Analytical biochemistry》2015
We have designed a simple and novel electrochemical biosensor based on glassy carbon electrode (GCE) for DNA detection. GCE was modified with reduced graphene oxide (RGO) and gold nanoparticles (AuNPs) by the electrochemical method, which is helpful for immobilization of thiolated bioreceptors. The electrode modification processes were characterized by scanning electron microscopy (SEM) and electrochemical methods. Then a single-stranded DNA (ssDNA) probe for BRCA1 5382 insC mutation detection was immobilized on the modified electrode for a specific time. The experimental conditions, such as probe immobilization time and target DNA (complementary DNA) hybridization time and temperature with probe DNA, were optimized using electrochemical methods. The electrochemical response for DNA hybridization and synthesis was measured using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) methods. The calibration graph contains two linear ranges; the first part is in the range of 3.0 × 10−20 to 1.0 × 10−12 M, and the second segment part is in the range of 1.0 × 10−12 to 1.0 × 10−7 M. The biosensor showed excellent selectivity for the detection of the complementary sequences from noncomplementary sequences, so it can be used for detection of breast cancer. 相似文献
997.
Krishnaveni Mohareer Sudhir Sahdev Seyed E. Hasnain 《Journal of cellular biochemistry》2013,114(4):899-907
p53 protein, the central molecule of the apoptosis pathway, is mutated in 50% of the human cancers. Of late, p53 homologues have been identified from different invertebrates including Drosophila melanogaster, Caenorhabditis elegans, Squid, and Clams. We report the identification of a p53‐like protein in Spodoptera frugiperda (Sf9) insect cells, which is activated during oxidative stress, caused by exposure to UV‐B or H2O2, and binds to p53 consensus DNA binding motifs as well as other p53 cognate motifs. Sf9 p53 motif‐binding protein is similar to murine and Drosophila p53 in terms of molecular size, which is around 50–60 kDa, as evident from UV cross‐linking, and displays DNA binding characteristics similar to both insect and vertebrate p53 as seen from electrophoretic mobility shift assays. The N‐terminal sequencing of the purified Sf9 p53 motif‐binding protein reveals extensive homology to the pro‐apoptotic FK‐506 binding protein (FKBP‐46), earlier identified in Sf9 cells as a factor which interacts with murine casein kinase. FKBP, an evolutionarily conserved protein of mammalian origin functions as a pro‐apoptotic factor. Identification of FKBP‐46 as a novel p53 motif‐binding protein in insect cells adds a new facet to our understanding of the mechanisms of apoptosis under oxidative stress in the absence of a typical p53 homologue. J. Cell. Biochem. 114: 899–907, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
998.
Umbelliprenin shows antitumor,antiangiogenesis, antimetastatic,anti‐inflammatory,and immunostimulatory activities in 4T1 tumor‐bearing Balb/c mice 下载免费PDF全文
Mohsen Rashidi Ahad Khalilnezhad Davar Amani Hamidreza Jamshidi Ahad Muhammadnejad Ali Bazi Seyed Ali Ziai 《Journal of cellular physiology》2018,233(11):8908-8918
Umbelliprenin (UMB) has shown various pharmacological properties in vitro. We investigated the antineoplastic and immunostimulatory effects of UMB in 4T1 mammary‐tumor‐bearing mice. Two‐hundred microliter of UMB (12.5 mg/ml) was intraperitoneally administrated to healthy and tumor‐bearing female Balb/c mice for a period of 18 days. Data was analyzed using GraphPad Prism 5 software for Windows (version 5, La Jolla, CA). UMB caused a significant decrease in tumor size (P < 0.01). Serum interferon gamma (IFNγ) was augmented in both healthy and tumor‐bearing animals (P < 0.01), and IL‐4 declined in healthy animals (P < 0.01) treated with UMB. Expressions of Ki‐67, VEGF, CD31, MMP2, MMP9, VCAM1, and NF‐κB were significantly decreased in tumors from UMB‐treated animals (P < 0.001), whereas E‐Cadherin and TNFR1 expressions were markedly increased (P < 0.001). The rates of liver and lung metastases in UMB‐administrated animals were smaller compared to the control. UMB can potently inhibit tumor growth, angiogenesis, metastasis, and inflammation and potentiate an antitumor immune response in vivo. However, further investigations are required to evaluate the UMB mechanisms of action in cancerous cells. 相似文献
999.
A Chimeric protein of CFA/I,CS6 subunits and LTB/STa toxoid protects immunized mice against enterotoxigenic Escherichia coli 下载免费PDF全文
Narges Zeinalzadeh Ali Hatef Salmanian Goli Goujani Jafar Amani Ghasem Ahangari Asal Akhavian Mahyat Jafari 《Microbiology and immunology》2017,61(7):272-279
1000.
Farnaz Zahedifard Elham Gholami Tahereh Taheri Yasaman Taslimi Fatemeh Doustdari Negar Seyed Fatemeh Torkashvand Claudio Meneses Barbara Papadopoulou Shaden Kamhawi Jesus G. Valenzuela Sima Rafati 《PLoS neglected tropical diseases》2014,8(3)