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71.
Accuracy of genomic selection for age at puberty in a multi‐breed population of tropically adapted beef cattle 下载免费PDF全文
M. M. Farah A. A. Swan M. R. S. Fortes R. Fonseca S. S. Moore M. J. Kelly 《Animal genetics》2016,47(1):3-11
Genomic selection is becoming a standard tool in livestock breeding programs, particularly for traits that are hard to measure. Accuracy of genomic selection can be improved by increasing the quantity and quality of data and potentially by improving analytical methods. Adding genotypes and phenotypes from additional breeds or crosses often improves the accuracy of genomic predictions but requires specific methodology. A model was developed to incorporate breed composition estimated from genotypes into genomic selection models. This method was applied to age at puberty data in female beef cattle (as estimated from age at first observation of a corpus luteum) from a mix of Brahman and Tropical Composite beef cattle. In this dataset, the new model incorporating breed composition did not increase the accuracy of genomic selection. However, the breeding values exhibited slightly less bias (as assessed by deviation of regression of phenotype on genomic breeding values from the expected value of 1). Adding additional Brahman animals to the Tropical Composite analysis increased the accuracy of genomic predictions and did not affect the accuracy of the Brahman predictions. 相似文献
72.
Khalid Alanazi Bassam A. Alahmadi Ahmed Alhimaidi Faisal M. Abou-Tarboush Mohammad Abul Farah Ahmed Mahmoud Mohamed Alfaifi 《Saudi Journal of Biological Sciences》2016,23(1):87-91
A spermatic granuloma is a chronic inflammatory reaction produced in response to extravasated sperm within the intertubular connective tissue. The present study investigates the possible toxic effects of water extract of Heliotropium bacciferum on the reproductive system of male albino rats and the associated potential for the development of spermatic granulomas. H. bacciferum is a herbal plant used in traditional medicine and reported to have cytotoxic effects due to pyrrolizidine alkaloids. Histological examinations revealed no changes in the tissues of the testes, although, some changes were detected in the cauda epididymis, the most important of which was the development of small lesions of spermatic granulomas. Clear gaps were observed between the epithelial linings of the epididymal tubules. 相似文献
73.
Harold L. Asch Robert Z. Vinci Jae Y. Chang Farah Natoli Daniel L. Stoler Garth R. Anderson Bonnie B. Asch 《Cell biology international》1993,17(10):961-968
Amplified expression of the endogenous retrotransposons, intracisternal A particles (IAPs) and murine leukemia virus-related elements (MLVEs), along with decreased expression of VL30 elements frequently occurs during mouse mammary tumorigenesis. We have now analyzed the expression of these retroelements during the normal developmental and differentiation cycle of the mammary gland as found in virgin, pregnant, lactating, and post-lactation adult female BALB/c mice. Retrotransposon expression was either unchanged or decreased during the progressive stages of the cycle compared to virgin tissue. Likewise, growth of mammary epithelial cells in primary culture had little or no effect on expression of IAPs, MLVEs and VL30 sequences. Thus, the dramatic changes involving these retrotransposons in many mouse mammary tumors appear unrelated to any normal state. 相似文献
74.
Farah El-Turk Bruno Fauvet Amer Ashrafi Hajer Ouertatani-Sakouhi Min-Kyu Cho Marilisa Neri Michele Cascella Ursula Rothlisberger Florence Pojer Markus Zweckstetter Hilal Lashuel 《PloS one》2012,7(9)
Macrophage Migration Inhibitory Factor (MIF) is a key mediator of inflammatory responses and innate immunity and has been implicated in the pathogenesis of several inflammatory and autoimmune diseases. The oligomerization of MIF, more specifically trimer formation, is essential for its keto-enol tautomerase activity and probably mediates several of its interactions and biological activities, including its binding to its receptor CD74 and activation of certain signaling pathways. Therefore, understanding the molecular factors governing the oligomerization of MIF and the role of quaternary structure in modulating its structural stability and multifunctional properties is crucial for understanding the function of MIF in health and disease. Herein, we describe highly conserved intersubunit interactions involving the hydrophobic packing of the side chain of Leu46 onto the β-strand β3 of one monomer within a hydrophobic pocket from the adjacent monomer constituted by residues Arg11, Val14, Phe18, Leu19, Val39, His40, Val41, Val42, and Pro43. To elucidate the structural significance of these intersubunit interactions and their relative contribution to MIF’s trimerization, structural stability and catalytic activity, we generated three point mutations where Leu46 was replaced by glycine (L46G), alanine (L46A) and phenylalanine (L46F), and their structural properties, stability, oligomerization state, and catalytic activity were characterized using a battery of biophysical methods and X-ray crystallography. Our findings provide new insights into the role of the Leu46 hydrophobic pocket in stabilizing the conformational state of MIF in solution. Disrupting the Leu46 hydrophobic interaction perturbs the secondary and tertiary structure of the protein but has no effect on its oligomerization state. 相似文献
75.
Ivy Grace Umadhay Pait Shigeru Kitani Farah Wahidah Roslan Dana Ulanova Masayoshi Arai Haruo Ikeda Takuya Nihira 《Journal of industrial microbiology & biotechnology》2018,45(2):77-87
The genome of streptomycetes has the ability to produce many novel and potentially useful bioactive compounds, but most of which are not produced under standard laboratory cultivation conditions and are referred to as silent/cryptic secondary metabolites. Streptomyces lavendulae FRI-5 produces several types of bioactive compounds. However, this strain may also have the potential to biosynthesize more useful secondary metabolites. Here, we activated a silent biosynthetic gene cluster of an uncharacterized compound from S. lavendulae FRI-5 using heterologous expression. The engineered strain carrying the silent gene cluster produced compound 5, which was undetectable in the culture broth of S. lavendulae FRI-5. Using various spectroscopic analyses, we elucidated the chemical structure of compound 5 (named lavendiol) as a new diol-containing polyketide. The proposed assembly line of lavendiol shows a unique biosynthetic mechanism for polyketide compounds. The results of this study suggest the possibility of discovering more silent useful compounds from streptomycetes by genome mining and heterologous expression. 相似文献
76.
Mohammad Hadi Karbalaie Niya Hossein Keyvani Fahimeh Safarnezhad Tameshkel Mostafa Salehi-Vaziri Sedigheh Teaghinezhad-S Farah Bokharaei Salim Seyed Hamid Reza Monavari Davod Javanmard 《Translational oncology》2018,11(3):593-598
Human papillomavirus (HPV) is a common viral infection worldwide associated with a variety of cancers. The integration of the HPV genome in these patients causes chromosomal instability and triggers carcinogenesis. The aim of this study was to investigate the HPV-16 genome physical status in four major cancers related to HPV infection. Formalin-fixed paraffin-embedded blocks from our previous projects on head and neck, colorectal, penile, and cervical cancers were collected, and HPV-16–positive specimens were used for further analysis. The DNA extraction copy number of E2 and E7 genes was calculated by qualitative real-time PCR method. Serially diluted standards that were cloned in PUC57 plasmid were used. Standard curve and melting curve analysis was used for quantification. Of the 672 specimens studied, 76 (11.3%) were HPV-16 positive. We found that 35.6% (16/45) were integrated. Statistical analysis showed that there were significant correlations between integration of HPV-16 and cervical cancer end-stage carcinogenesis (P < .0001), episomal form, and ASCUS lesions (P = .045). Significant correlation in penile cancer patients was seen between the episomal form and high-grade cancer stage (P = .037). Integration is a major factor in the carcinogenesis mechanism of HPV and has different prevalence in various cancers with a higher rate in progression except in penile cancer. 相似文献
77.
Sheikh Farah Jin Yan Pasumarthi Kishore B.S. Kardami Elissavet Cattini Peter A. 《Molecular and cellular biochemistry》1997,176(1-2):89-97
Aspergillus fumigatus is a highly pathogenic fungus causing a wide spectrum of diseases in immunocompromised as well as immunocompetent hosts. The present work was undertaken to evaluate the cytotoxic nature of fractionated antigens of A. fumigatus against the mammalian cell lines (J774, RAW, CHO and L929). An enriched protein antigenic fraction of A. fumigatus was subjected to con A Sepharose and phenyl Sepharose chromatography. Antigenic fractions, ConAub (conA unbound) and PSC III (fraction III of phenyl Sepharose column) containing low mw antigens showed higher cytotoxicity as compared to other antigenic fractions. PSC III was further purified on HPLC resulting in an 18 kDa homogeneous protein. The purified protein showed high ELISA absorbance values for specific IgG and IgE antibodies in sera of ABPA patients. Monoclonal antibody raised against Asp fl, a major allergen/antigen of A. fumigatus recognised the purified 18 kDa by ELISA and western blot. The 18 kDa allergen/antigen or Asp fl showed similar toxicity towards all the four cell lines (macrophage and fibroblast) with an IC50 of 75 ng/ml or 4.16 nM. Reduction in toxicity of 18 kDa at low temperatures and potentiation in presence of ammonium chloride and monensin indicates mechanism of internalisation of 18 kDa in eukaryotic cells is similar to -sarcin. The present work shows that the 18 kDa allergen/antigen (Asp fl) is a major cytotoxin secreted by A. fumigatus which may play multiple roles in the pathogenesis of Aspergillosis through allergenicity, antigenicity and cytotoxicity. (Mol Cell Biochem 167: 89-97, 1997) 相似文献
78.
Mdm12p, a Component Required for Mitochondrial Inheritance That Is Conserved between Budding and Fission Yeast 总被引:15,自引:1,他引:14 下载免费PDF全文
Saccharomyces cerevisiae cells lacking the MDM12 gene product display temperature-sensitive growth and possess abnormally large, round mitochondria that are defective for inheritance by daughter buds. Analysis of the wild-type MDM12 gene revealed its product to be a 31-kD polypeptide that is homologous to a protein of the fission yeast Schizosaccharomyces pombe. When expressed in S. cerevisiae, the S. pombe Mdm12p homolog conferred a dominant-negative phenotype of giant mitochondria and aberrant mitochondrial distribution, suggesting partial functional conservation of Mdm12p activity between budding and fission yeast. The S. cerevisiae Mdm12p was localized by indirect immunofluorescence microscopy and by subcellular fractionation and immunodetection to the mitochondrial outer membrane and displayed biochemical properties of an integral membrane protein. Mdm12p is the third mitochondrial outer membrane protein required for normal mitochondrial morphology and distribution to be identified in S. cerevisiae and the first such mitochondrial component that is conserved between two different species. 相似文献
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