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Endometrial cancer is the most common gynecologic malignancy and is associated with increased morbidity each year, including young people. However, its mechanisms of proliferation and progression are not fully elucidated. It is well known that abnormal glycosylation is involved in oncogenesis, and fucosylation is one of the most important types of glycosylation. In particular, fucosyltransferase 8 (FUT8) is the only FUT responsible for α1, 6-linked fucosylation (core fucosylation), and it is involved in various physiological as well as pathophysiological processes, including cancer biology. Therefore, we aimed to identify the expression of FUT8 in endometrial endometrioid carcinoma and investigate the effect of the partial silencing of the FUT8 gene on the cell proliferation of Ishikawa cells, an epithelial-like endometrial cancer cell line. Quantitative real-time PCR analysis showed that FUT8 gene expression was significantly elevated in the endometrial endometrioid carcinoma, compared to the normal endometrium. The immunostaining of FUT8 and Ulex europaeus Agglutinin 1 (UEA-1), a kind of lectin family specifically binding to fucose, was detected endometrial endometrioid carcinoma. The proliferation assay showed FUT8 partial knockdown by transfection of siRNA significantly suppressed the proliferation of Ishikawa cells, concomitant with the upregulation in the gene expressions associated with the interesting pathways associated with de-ubiquitination, aspirin trigger, mesenchymal-epithelial transition (MET) et al. It was suggested that the core fucosylation brought about by FUT8 might be involved in the proliferation of endometrial endometrioid carcinoma cells.  相似文献   
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A clinically‐relevant, drug‐resistant mutant of HIV‐1 protease (PR), termed Flap+(I54V) and containing L10I, G48V, I54V and V82A mutations, is known to produce significant changes in the entropy and enthalpy balance of drug‐PR interactions, compared to wild‐type PR. A similar mutant, Flap+(I54A), which evolves from Flap+(I54V) and contains the single change at residue 54 relative to Flap+(I54V), does not. Yet, how Flap+(I54A) behaves in solution is not known. To understand the molecular basis of V54A evolution, we compared nuclear magnetic resonance (NMR) spectroscopy, fluorescence spectroscopy, isothermal titration calorimetry, and enzymatic assay data from four PR proteins: PR (pWT), Flap+(I54V), Flap+(I54A), and Flap+(I54), a control mutant that contains only L10I, G48V and V82A mutations. Our data consistently show that selection to the smaller side chain at residue 54, not only decreases inhibitor affinity, but also restores the catalytic activity.  相似文献   
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Casearia sylvestris is an endemic tree of the Latin America that the essential oil (EO) has anti-inflammatory and gastroprotective actions. This study evaluates the chemical composition of the EO from the volatile fractions of in natura, fresh, and dried C. sylvestris var. sylvestris and var. lingua leaves. For both varieties, the dried leaves presented higher EO yield as compared to fresh leaves. The major EO chemical components were (E)-caryophyllene, α-humulene, germacrene D, bicyclogermacrene, spathulenol, caryophyllene oxide, and humulene epoxide II. In both varieties, the content of sesquiterpene hydrocarbons decreased and oxygenated sesquiterpenes increased on going from in natura to fresh and dried leaves, which indicated that leaf drying and hydrodistillation modified the volatile composition. The results also suggested that bicyclogermacrene and (E)-caryophyllene were oxidized during processing, to generate spathulenol and caryophyllene oxide, respectively. C. sylvestris varieties and in natura, fresh, and dried leaves differed in terms of the chemical composition of volatiles, which could affect the EO biological activities.  相似文献   
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Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. Genetic polymorphisms in the 3′UTR region of the CXCL12 (rs1801157) and TP53 codon 72 (rs1042522) genes may contribute to susceptibility to childhood ALL because they affect some important processes, such as metastasis regulation and tumor suppression. Thus the objective of the present study was to detect the frequency of two genetic polymorphisms in ALL patients and controls and to add information their impact on genetic susceptibility and prognosis. The CXCL12 and TP53 polymorphisms were tested in 54 ALL child patients and in 58 controls by restriction fragment length polymerase chain reaction and allelic specific chain reaction techniques, respectively. The frequencies of both allelic variants were higher in ALL patients than in the controls and indicated a positive association: OR = 2.44; 95 % CI 1.05–5.64 for CXCL12 and OR = 2.20; 95 % CI 1.03–4.70 for TP53. Furthermore, when the two genetic variants were analyzed together, they increased significantly more than fivefold the risk of this neoplasia development (OR = 5.24; 95 % CI 1.39–19.75), indicating their potential as susceptibility markers for ALL disease and the relevance of the allelic variant combination to increased risk of developing malignant tumors. Future studies may indicate a larger panel of genes involved in susceptibility of childhood ALL and other hematological neoplasias.  相似文献   
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Circadian rhythms are regarded as essentially ubiquitous features of animal behavior and are thought to confer important adaptive advantages. However, although circadian systems of rodents have been among the most extensively studied, most comparative biology is restricted to a few related species. In this study, the circadian organization of locomotor activity was studied in the subterranean, solitary north Argentinean rodent, Ctenomys knightii. The genus, Ctenomys, commonly known as Tuco‐tucos, comprises more than 50 known species over a range that extends from 12°S latitude into Patagonia, and includes at least one social species. The genus, therefore, is ideal for comparative and ecological studies of circadian rhythms. Ctenomys knightii is the first of these to be studied for its circadian behavior. All animals were wild caught but adapted quickly to laboratory conditions, with clear and precise activity‐rest rhythms in a light‐dark (LD) cycle and strongly nocturnal wheel running behavior. In constant dark (DD), the rhythm expression persisted with free‐running periods always longer than 24 h. Upon reinstatement of the LD cycle, rhythms resynchronized rapidly with large phase advances in 7/8 animals. In constant light (LL), six animals had free‐running periods shorter than in DD, and 4/8 showed evidence of “splitting.” We conclude that under laboratory conditions, in wheel‐running cages, this species shows a clear nocturnal rhythmic organization controlled by an endogenous circadian oscillator that is entrained to 24 h LD cycles, predominantly by light‐induced advances, and shows the same interindividual variable responses to constant light as reported in other non‐subterranean species. These data are the first step toward understanding the chronobiology of the largest genus of subterranean rodents.  相似文献   
100.
Of the 19 strains of Rhizopus delemar deposited as Rhizopus oryzae, seven of them, NBRC 4726, NBRC 4734, NBRC 4746, NBRC 4754, NBRC 4773, NBRC 4775, and NBRC 4801, completely hydrolyzed exogenous sucrose and fructooligosaccharides. The sucrose-hydrolyzing enzyme was purified from the culture filtrate of R. delemar NBRC 4754 and classified to β-fructofuranosidase, similar to that of Amylomyces rouxii CBS 438.76. Fragments including β-fructofuranosidase genes (sucA) of seven strains of R. delemar and A. rouxii CBS 438.76 were amplified and sequenced by PCR with degenerated primers synthesized on the basis of the internal amino acid sequences of purified enzymes and successive inverse PCR. Nucleotide sequences of the obtained fragments revealed that open reading frames of 1,569 bp have no intron and encode 522 amino acids. The presumed proteins contained the typical domain of the glycoside hydrolase 32 family, including β-fructofuranosidase, inulinase, levanase, and fructosyltransferases. Amino acid sequences of SucA proteins from the seven strains of R. delemar were identical and showed 90.0 % identity with those of A. rouxii CBS 438.76. A dendrogram constructed from these amino acid sequences showed that SucA proteins are more closely related to yeast β-fructofuranosidases than to other fungal enzymes.  相似文献   
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