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71.
In the present study, we used an explant culture system of the human decidual tissues involving a new sampling method for investigating the productivity of immunoreactive prolactin (IR-PRL) for a 5 day period in labored and nonlabored deliveries. The maximal release of IR-PRL in the incubation medium for each 24 hour interval was achieved from the 2nd to the 3rd day of culture in both groups, which was 145.2 +/- 14.0 ng/ml/10 mg w.w. (mean +/- s.e.; n = 7) in the labor group and 101.5 +/- 16.3 ng/ml/10 mg w.w. (mean +/- s.e.; n = 4) in the nonlabor group. The release of IR-PRL in both groups was not significantly different for the first 3 days. However, the amount of IR-PRL released in the nonlabor group was 50 to 70% of that of the labor group. The tissue content of IR-PRL in both groups ranged between 3.0 and 5.0 ng/ml/10 mg w.w. From these results, it was concluded that 1) our explant culture system for the human decidual tissues produced considerably more IR-PRL than those previously reported and 2) productivity of IR-PRL was lower in nonlabored delivery than in labored delivery and 3) since the tissue content of IR-PRL for each 24 hour interval was very small, it should be strongly emphasized that the production and release of IR-PRL takes place simultaneously in the human decidual tissues.  相似文献   
72.
β‐arrestins seem to have a role in endocytosis and desensitization of somatostatin receptor subtype 2 (sst2) and could be associated with the responsiveness to somatostatin receptor ligands (SRL) in patients with acromegaly. To investigate the in vivo correlation between β‐arrestins 1 and 2 with sst2, sst5 and dopamine receptor subtype 2 (D2) expressions, and the association of β‐arrestins with response to first‐generation SRL and invasiveness in somatotropinomas. β‐arrestins 1 and 2, sst2, sst5 and D2 mRNA expressions were evaluated by quantitative real‐time RT‐PCR on tumoral tissue of 96 patients. Moreover, sst2 and sst5 protein expressions were also evaluated in 40 somatotropinomas by immunohistochemistry. Response to SRL, defined as GH <1 μg/l and normal IGF‐I levels, was assessed in 40 patients. The Knosp‐Steiner criteria were used to define invasiveness. Median β‐arrestin 1, β‐arrestin 2, sst2, sst5 and D2 mRNA copy numbers were 478; 9375; 731; 156 ; and 3989, respectively. There was a positive correlation between β‐arrestins 1 and 2 (= 0.444, < 0.001). However, no correlation between β‐arrestins and sst2, sst5 (mRNA and protein levels) or D2 was found. No association was found between β‐arrestins expression and SRL responsiveness or tumour invasiveness. Although previous data suggest a putative correlation between β‐arrestins and sst2, our data clearly indicated that no association existed between β‐arrestins and sst2, sst5 or D2 expression, nor with response to SRL or tumour invasiveness. Therefore, further studies are required to clarify whether β‐arrestins have a role in the response to treatment with SRL in acromegaly.  相似文献   
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The induction of H3K9 methylation by PIWIL4 at the p16Ink4a locus   总被引:1,自引:0,他引:1  
The field of epigenetics has made progress by the identification of the small RNA-mediated epigenetic modification. However, little is known about the key proteins. Here, we report that the human PIWI-like family is a candidate protein that is involved in the pathway responsible for chromatin remodeling. The PIWI-like family proteins, expressed as the Flag-fusion proteins, formed a bulky body and localized to the nuclear periphery. Transient transfection of PIWI-like 4 (PIWIL4), only member of the PIWI-like family that was ubiquitously expressed in human tissues, induced histone H3 lysine 9 methylation at the p16(Ink4a) (CDKN2A) locus. The elevated level of histone methylation resulted in the downregulation of the p16(Ink4a) gene. These results suggest PIWIL4 plays important roles in the chromatin-modifying pathway in human somatic cells.  相似文献   
77.
We assembled a dataset tabulating the weights of Thai and Indonesian mangrove trees that we measured between 1982 and 2001. We selected four Thai study sites in Phang Nga, Ranong, Satun, and Trat Provinces and one site in eastern Indonesia on Halmahera Island in Maluku Province. The stands in Ranong Province and on Halmahera Island were in primary forests with data collected in the 1980s and the remaining stands were in secondary forests with data collected later. We collected 124 tree samples from ten species (Avicennia alba, Bruguiera cylindrica, B. gymnorrhiza, Ceriops tagal, Rhizophora apiculata, R. mucronata, Sonneratia alba, S. caseolaris, Xylocarpus granatum, and X. moluccensis) and measured the root weights of 32 individuals of nine species (A. alba, B. cylindrica, B. gymnorrhiza, C. tagal, R. apiculata, R. mucronata, S. alba, S. caseolaris, and X. granatum). All sampled trees were subjected to a standardized protocol to obtain aboveground weights. The trunks were divided into horizontal segments from which the leaves and branches were collected separately. Roots were collected by winching them out of the ground, by trench digging, or by complete excavation. Thus, we were able to compile the weights of the trunk, branches, leaves, and roots of each tree sampled. Aerial roots were included in root weight measurements, although they were collected above ground. We compiled separate lists of trunk diameters, trunk heights, heights of the lowest living branches, and the heights of aerial roots on the trunks of trees in different size categories. Our dataset includes a wide range of tree sizes (maximum trunk diameter 48.9 cm), geographical locations (1°10′N–12°24′N, 98°32′E–123°49′E) and organ weights (trunks, branches, leaves, and roots), and therefore should prove useful in future biomass studies of mangrove forests.  相似文献   
78.

Caffeic acid (3,4-dihydroxycinnamic acid) serves as a building block for thermoplastics and a precursor for biologically active compounds and was recently produced from glucose by microbial fermentation. To produce caffeic acid from inedible cellulose, separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) reactions were compared using kraft pulp as lignocellulosic feedstock. Here, a tyrosine-overproducing Escherichia coli strain was metabolically engineered to produce caffeic acid from glucose by introducing the genes encoding a 4-hydroxyphenyllactate 3-hydroxylase (hpaBC) from Pseudomonas aeruginosa and tyrosine ammonia lyase (fevV) from Streptomyces sp. WK-5344. Using the resulting recombinant strain, the maximum yield of caffeic acid in SSF (233 mg/L) far exceeded that by SHF (37.9 mg/L). In the SSF with low cellulase loads (≤2.5 filter paper unit/g glucan), caffeic acid production was markedly increased, while almost no glucose accumulation was detected, indicating that the E. coli cells experienced glucose limitation in this culture condition. Caffeic acid yield was also negatively correlated with the glucose concentration in the fermentation medium. In SHF, the formation of by-product acetate and the accumulation of potential fermentation inhibitors increased significantly with kraft pulp hydrolysate than filter paper hydrolysate. The combination of these inhibitors had synergistic effects on caffeic acid fermentation at low concentrations. With lower loads of cellulase in SSF, less potential fermentation inhibitors (furfural, 5-hydroxymethyfurfural, and 4-hydroxylbenzoic acid) accumulated in the medium. These observations suggest that glucose limitation in SSF is crucial for improving caffeic acid yield, owing to reduced by-product formation and fermentation inhibitor accumulation.

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79.
Design, syntheses, and structure-activity relationships of a novel class of 2-{3-oxospiro[isobenzofuran-1(3H),4'-piperidin]-1'-yl}benzimidazole NPY Y5 receptor antagonists are described. The benzimidazole structures were newly designed based on the urea linkage of our prototype Y5 receptor antagonists (2 and 3). By optimizing substituents on the benzimidazole core part of the lead compound 5a, we were able to develop a potent, orally available, and brain-penetrable Y5 selective antagonist (5k).  相似文献   
80.
A new series of quinazolines that function as CCR4 antagonists were discovered during the screening of our corporate compound libraries. Subsequent compound optimization elucidated the structure-activity relationships and led the identification of 2-(1,4'-bipiperidine-1'-yl)-N-cycloheptyl-6,7-dimethoxyquinazolin-4-amine 14a, which showed potent inhibition in the [(35)S]GTPgammaS-binding assay (IC(50)=18nM). This compound also inhibited the chemotaxis of human and mouse CCR4-expressing cells (IC(50)=140nM, 39nM).  相似文献   
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