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61.
Qualitative and quantitative differences in carrageenan composition of gametophytes of the rhodophyte Mastocarpus stellatus (Gigartinales) were observed in this study. Carrageenans in gametophytes belong to the kappa family (κ-, ι-, ν-, μ-carrageenan). The dominant fractions were κ- and ι-carrageenan (more than 80 % of the total carrageenans). Mean total carrageenan content in gametophytes was of 37.32?±?1.21 % DW. Spatial and seasonal variations were observed, mainly related to changes on environmental and oceanographic factors and the role of carrageenans in adapting the fronds to these changes. Maximum values in carrageenan content were observed for San Román (Biscay Bay) in May and for Laxe and Mougás (Atlantic coast) in June. The results of this study indicated that spatial differences in carrageenan content were due to interactions of different factors, rather than the effect of a single factor. Fronds from San Román had higher carrageenan content (43.23?±?1.87 % DW) than those collected at two sites of the Atlantic coast, Mougás and Laxe (32.20?±?1.14 % DW). San Román is exposed to the open sea, windy and oriented to the north, and the water temperature is higher in summer than in the Atlantic coast. However, seasonal variations in carrageenan content resulted to be more related to other factors directly correlated with the input of energy in the ecosystems (irradiance, sunshine hours and insolation). Thus, carrageenan content began to increase in early spring when the number of sunlight hours increased. Maximum values were reached in late spring or early summer, just before maximum values of irradiance and air temperature were achieved.  相似文献   
62.
Recent studies have demonstrated that bone marrow stromal cells can undergo adipogenesis or osteoblastogenesis in vivo, and in vitro, and that peroxisome proliferator-activated receptor gamma (PPAR gamma) plays a central role in the control of adipocyte differentiation. In the present study, we treated a murine stromal cell line (TMS-14) with a cocktail of dexamethasone, insulin and glucose (DIG cocktail), which caused the cells to convert to fat-laden cells with adipocyte-like morphology. We also exposed TMS-14 cells to DIG cocktail followed by 15-deoxy Delta(12,14)-prostaglandin J2 (15d-PGJ2), a ligand of PPAR gamma, interleukin- 11 (IL-11), 9-cis retinoic acid (9-cis RA) and vitamin K2. 15d-PGJ2 enhanced DIG cocktail-induced adipogenesis, whereas IL-11, 9-cis RA and vitamin K2 each inhibited adipogenesis induced by DIG cocktail. The gene expressions of four adipogenesis markers, PPAR gamma 2, adipocyte P2 (aP2), adipocyte determination and differentiation factor 1 (ADD1), and fatty acid synthase (FAS) were enhanced by DIG cocktail and these expressions were more enhanced by 15d-PGJ2, in contrast they were attenuated by 9-cis RA. IL-11 also attenuated the adipogenesis markers except ADD1. Western blotting showed that 15d-PGJ2 enhanced the levels of PPAR gamma, C/EBP alpha and RXR alpha proteins, while IL-11 and 9-cis RA decreased the level of PPAR gamma protein, but not C/EBP alpha protein and vitamin K2 decreased the level of C/EBP alpha protein. We also tested the effect of 15d-PGJ2 on osteoblastogenesis, using TMS-12 cells, another stromal cell clone from the same mouse, which differentiate into osteoblasts spontaneously. 15d-PGJ2 did not affect osteoblastogenesis, as detected by von Kossa staining and Cbfa-1 gene expression. These data indicate that 15d-PGJ2 enhances the expression of both PPAR gamma and C/EBP alpha and as a result it stimulates adipogenesis in murine bone marrow cells.  相似文献   
63.
Process for the isolation of preparative quantities of

Specific enzymes were used to hydrolyse sugarbeet pulp to facilitate the isolation of

in preparative amounts. The feruloylated arabinose disaccharide was purified by chromatography on Sephadex LH-20 and Bio-Gel P-2 and the structure confirmed by NMR and UV spectroscopy and high-performance liquid chromatography.  相似文献   
64.
White blood cell (WBC) count is a common clinical measure from complete blood count assays, and it varies widely among healthy individuals. Total WBC count and its constituent subtypes have been shown to be moderately heritable, with the heritability estimates varying across cell types. We studied 19,509 subjects from seven cohorts in a discovery analysis, and 11,823 subjects from ten cohorts for replication analyses, to determine genetic factors influencing variability within the normal hematological range for total WBC count and five WBC subtype measures. Cohort specific data was supplied by the CHARGE, HeamGen, and INGI consortia, as well as independent collaborative studies. We identified and replicated ten associations with total WBC count and five WBC subtypes at seven different genomic loci (total WBC count-6p21 in the HLA region, 17q21 near ORMDL3, and CSF3; neutrophil count-17q21; basophil count- 3p21 near RPN1 and C3orf27; lymphocyte count-6p21, 19p13 at EPS15L1; monocyte count-2q31 at ITGA4, 3q21, 8q24 an intergenic region, 9q31 near EDG2), including three previously reported associations and seven novel associations. To investigate functional relationships among variants contributing to variability in the six WBC traits, we utilized gene expression- and pathways-based analyses. We implemented gene-clustering algorithms to evaluate functional connectivity among implicated loci and showed functional relationships across cell types. Gene expression data from whole blood was utilized to show that significant biological consequences can be extracted from our genome-wide analyses, with effect estimates for significant loci from the meta-analyses being highly corellated with the proximal gene expression. In addition, collaborative efforts between the groups contributing to this study and related studies conducted by the COGENT and RIKEN groups allowed for the examination of effect homogeneity for genome-wide significant associations across populations of diverse ancestral backgrounds.  相似文献   
65.
Methyl donor (MD: folate, vitamin B12 and choline) deficiency causes hyperhomocysteinemia, a risk factor for cardiovascular diseases. However, the mechanisms of the association between MD deficiency, hyperhomocysteinemia, and cardiomyopathy remain unclear. Therefore, we performed a proteomic analysis of myocardium of pups from rat dams fed a MD-depleted diet to understand the impact of MD deficiency on heart at the protein level. Two-dimension gel electrophoresis and mass spectrometry-based analyses allowed us to identify 39 proteins with significantly altered abundance in MD-deficient myocardium. Ingenuity Pathway Analysis showed that 87% of them fitted to a single protein network associated with developmental disorder, cellular compromise and lipid metabolism. Concurrently increased protein carbonylation, the major oxidative post-translational protein modification, could contribute to the decreased abundance of many myocardial proteins after MD deficiency. To decipher the effect of MD deficiency on the abundance of specific proteins identified in vivo, we developed an in vitro model using the cardiomyoblast cell line H9c2. After a 4-day exposure to a MD-deprived (vs. complete) medium, cells were deficient of folate and vitamin B12, and released abnormal amounts of homocysteine. Western blot analyses of pup myocardium and H9c2 cells yielded similar findings for several proteins. Of specific interest is the result showing increased and decreased abundances of prohibitin and α-crystallin B, respectively, which underlines mitochondrial injury and endoplasmic reticulum stress within MD deficiency. The in vitro findings validate the MD-deficient H9c2 cells as a relevant model for studying mechanisms of the early metabolic changes occurring in cardiac cells after MD deprivation.  相似文献   
66.
Long-term exposure to cigarette smoke (CS) can have deleterious effects on lung epithelial cells including cell death and the initiation of inflammatory responses. CS-induced cell injury can elaborate cell surface signals and cellular byproducts that stimulate immune system surveillance. Our previous work has shown that the expression of ligands for the cytotoxic lymphocyte activating receptor NKG2D is enhanced in patients with COPD and that the induction of these ligands in a mouse model can replicate COPD pathologies. Here, we extend these findings to demonstrate a role for the NKG2D receptor in CS-induced pathophysiology and provide evidence linking nucleic acid-sensing endosomal toll-like receptor (TLR) signaling to COPD pathology through NKG2D activation. Specifically, we show that mice deficient in NKG2D exhibit attenuated pulmonary inflammation and airspace enlargement in a model of CS-induced emphysema. Additionally, we show that CS exposure induces the release of free nucleic acids in the bronchoalveolar lavage and that direct exposure of mouse lung epithelial cells to cigarette smoke extract similarly induces functional nucleic acids as assessed by TLR3, 7, and 9 reporter cell lines. We demonstrate that exposure of mouse lung epithelial cells to TLR ligands stimulates the surface expression of RAET1, a ligand for NKG2D, and that mice deficient in TLR3/7/9 receptor signaling do not exhibit CS-induced NK cell hyperresponsiveness and airspace enlargement. The findings indicate that CS-induced airway injury stimulates TLR signaling by endogenous nucleic acids leading to elevated NKG2D ligand expression. Activation of these pathways plays a major role in the altered NK cell function, pulmonary inflammation and remodeling related to long-term CS exposure.  相似文献   
67.
Bipolar microtubule attachment is central to genome stability. Here, we investigate the mitotic role of the fission yeast EB1 homologue Mal3. Mal3 shows dynamic inward movement along the spindle, initial emergence at the spindle pole body (SPB) and translocation towards the equatorial plane, followed by sudden disappearance. Deletion of Mal3 results in early mitotic delay, which is dependent on the Bub1, but not the Mad2, spindle checkpoint. Consistently, Bub1, but not Mad2, shows prolonged kinetochore localization. Double mutants between mal3 and a subset of checkpoint mutants, including bub1, bub3, mad3 and mph1, but not mad1 or mad2, show massive chromosome mis-segregation defects. In mal3bub1 mutants, both sister centromeres tend to remain in close proximity to one of the separating SPBs. Further analysis indicates that mis-segregated centromeres are exclusively associated with the mother SPB. Mal3, therefore, has a role in preventing monopolar attachment in cooperation with the Bub1/Bub3/Mad3/Mph1-dependent checkpoint.  相似文献   
68.
The expression of two genes encoding facilitated glucose transporter proteins was studied during the differentiation of the 3T3-L1 fibroblastic cell line into adipocytes. The mRNA encoding the widely expressed HepG2/brain glucose transporter (GTI) is detectable in fibroblasts and its abundance remains unchanged during differentiation. On the other hand, the mRNA encoding a glucose transporter protein (GTIII) localized exclusively to muscle and adipose tissue is undetectable in fibroblasts but present in adipocytes. GTIII mRNA is first expressed three days after differentiation of 3T3-L1 cells has begun. Similarly, it is not until 3 days following the initiation of differentiation that GTIII protein can be detected, as assayed either by Western immunoblot or indirect immunofluorescence. The latter technique localizes GTIII predominantly to the perinuclear region of the adipocyte. The appearance of GTIII in developing fat cells correlates temporally with the acquisition of an increased stimulation of hexose uptake by maximal concentrations of insulin. These data support the concept that the marked increase in hexose transport in adipocytes in response to insulin is dependent on the expression in these cells of a specific, hormone-regulatable transport protein.  相似文献   
69.
Dansyl derivatives of epsilon-N-mono-, epsilon-N-di-, and epsilon-N-trimethyllysine were resolved from other amino acids in proteins by the use of high-performance liquid chromatography. The system was tested with amino acid standard combinations as well as with acid-hydrolyzed proteins known to contain methylated residues. In all cases the methylated lysines were well resolved.  相似文献   
70.
Garcia M  Edqvist LE 《Theriogenology》1990,33(5):1091-1103
Five experiments were undertaken to investigate variation in progesterone concentrations as related to the collection and handling of samples of milk and blood, to determine reference values for progesterone and to evaluate clinical findings in relation to progesterone data from pure- and crossbred Zebu cattle reared in the Peruvian tropics. Whole-milk progesterone concentrations obtained from 12 Holstein x Nellore pregnant cows at hourly intervals over a 24-h period were highest immediately after milking; this peak was followed by a sharp drop over the next 3 h. Milk-fat content from 28 Brown Swiss x Nellore pregnant cows increased from 2.4% before milking to 6.7% afterwards (P < 0.05), whereas progesterone concentrations in whole milk increased from 18.4 to 59.5 nmol/1 (P < 0.05). Progesterone concentrations in fat-free milk were stable, with the exception of the fore-milk sample, which was lower than subsequent samples collected during milking (P < 0.05). Blood samples collected from 23 purebred, pregnant Nellore cows, were divided into four aliquots, and plasma and serum were harvested periodically over the next 120 h of storage at +4 degrees C, or in the shade at ambient air temperatures. The results indicate that blood samples can be stored unseparated at both temperatures studied for up to 3 h without severe loss of progesterone. Milk samples collected at different intervals during the luteal phase of the estrous cycle and during early and mid-pregnancy from crossbred cows showed no significant differences in progesterone concentrations between Days 9 to 13 of the cycle and Days 9 to 13 of gestation. Progesterone levels during advanced gestation were higher (P < 0.05). Out of 2,607 clinical examinations, the level of agreement between palpatory findings and progesterone determinations was 95.6 and 81.9% in diagnosing non-luteal and luteal structures, respectively. Significant differences in the level of agreement between palpators were found (P < 0.01). It is concluded that milk samples, preferably composite milk or strippings, must be consistently collected at the same stage of milking, and that centrifugation of blood samples should be done as soon as possible and not later than 3 h after collection.  相似文献   
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