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111.
Many imaging probes have been developed for a wide variety of imaging modalities. However, no optical imaging probe could be utilized for both microscopic and whole animal imaging. To fill the gap, the dual-wavelength fluorescent imaging nanoprobe was developed to simultaneously carry both visible-range fluorescent dye and near-infrared (NIR) dye. Emission scan confirms that the nanoprobe exhibits two separate peaks with strong fluorescent intensity in both visible and NIR ranges. Furthermore, the dual-wavelength fluorescent nanoprobe has high photostability and colloidal stability, as well as long shelf-life. In vitro cell culture experiments show that the nanoprobe has the ability to label different types of cells (namely, esophageal, prostate, fibroblast and macrophage cell) for fluorescent microscope imaging. More importantly, cell tracking experiments confirm that cell migration and distribution in various organs can be tracked in real time using in vivo whole-body NIR imaging and in vitro microscopic imaging, respectively.  相似文献   
112.
A new lignan, 9′-methoxypinoresinol (1), and two new glycosylated 5-hydroxymethylfurfurals, calofurfuralside A (2), and calofurfuralside B (3), together with nine known compounds (412) have been isolated from the active fractions, CHCl3 (IC50, 0.32 μg mL?1) and EtOAc (IC50, 0.55 μg mL?1) fractions of the leaves of Calotropis gigantea. Their structures were elucidated based on NMR and MS data. Among the isolated compounds, compounds 1 and 9 exhibited potent cytotoxicity against PANC-1 human pancreatic cancer cell line under the normoglycemic condition with IC50 values of 3.7 and 3.3 μM, respectively. 9′-Methoxypinoresinol (1) significantly inhibited the colony formation of PANC-1 cells in a concentration-dependent manner.  相似文献   
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Allergic diseases such as atopic dermatitis, rhinitis, asthma, and anaphylaxis are attractive research areas. Tyrosol (2-(4-hydroxyphenyl)ethanol) is a polyphenolic compound with diverse biological activities. In this study, we investigated whether tyrosol has anti-allergic inflammatory effects. Ovalbumin-induced active systemic anaphylaxis and immunoglobulin E-mediated passive cutaneous anaphylaxis models were used for the immediate-type allergic responses. Oral administration of tyrosol reduced the allergic symptoms of hypothermia and pigmentation in both animal models. Mast cells that secrete allergic mediators are key regulators on allergic inflammation. Tyrosol dose-dependently decreased mast cell degranulation and expression of inflammatory cytokines. Intracellular calcium levels and activation of inhibitor of κB kinase (IKK) regulate cytokine expression and degranulation. Tyrosol blocked calcium influx and phosphorylation of the IKK complex. To define the molecular target for tyrosol, various signaling proteins involved in mast cell activation such as Lyn, Syk, phosphoinositide 3-kinase (PI3K), and Akt were examined. Our results showed that PI3K could be a molecular target for tyrosol in mast cells. Taken together, these findings indicated that tyrosol has anti-allergic inflammatory effects by inhibiting the degranulation of mast cells and expression of inflammatory cytokines; these effects are mediated via PI3K. Therefore, we expect tyrosol become a potential therapeutic candidate for allergic inflammatory disorders.  相似文献   
116.
This paper presents a FORTRAN IV subroutine to calculate inbreedingand kinship coefficients from pedigree information in a diploidpopulation without self-fertilization. The user can specifythe number of ancestral generations to be taken into account.It is thus possible to determine contributions of succeedingancestral generations to the inbreeding and kinship coefficientsunder consideration. The subroutine is based on a recursiveprocedure that generates systematically all paths connectingtwo individuals, NP and NM, whose kinship coefficient is tobe calculated (or between the father NP and the mother NM ofthe individual whose inbreeding coefficient is to be calculated).These paths obey the following conditions: (i) a given pathdoes not contain the same parent—offspring link more thanonce; (ii) the vertex of a path is an ancestor common to individualsNP and NM, with a rank lower or equal to the parameter specifiedin input. Constraints regarding the size of the corpus of genealogicaldata and the storage method are discussed, as well as the interestof this subroutine compared to the existing ones. An exampleof application is given. Received on October 20, 1988; accepted on March 21, 1989  相似文献   
117.
Pseudomonas cepacia BY21 was found to produce glutaryl acylase that is capable of deacylating glutaryl-7-aminocephalosporanic acid (glutaryl-7-ACA) to 7-aminocephalosporanic acid (7-ACA), which is a starting material for semi-synthetic cephalosporin antibiotics. Amino acids of the reported glutaryl acylases from variousPseudomonas sp. strains show a high similarity (>93% identity). Thus, with the known nucleotide sequences ofPseudomonas glutaryl acylases in GenBank, PCR primers were designed to clone a glutaryl acylase gene fromP. cepacia BY21. The unknown β-subunit gene of glutaryl acylase from chromosomal DNA ofP. cepacia BY21 was cloned successfully by PCR. The β-subunit amino acids ofP. cepacia BY21 acylase (GenBank accession number AY948547) were similar to those ofPseudomonas diminuta KAC-1 acylase except that Asn408 ofP. diminuta KAC-1 acylase was changed to Leu408.  相似文献   
118.
There are tremendous drug candidates that suffer from insolubility in water. In the present study, it is shown that Coenzyme Q10 (CoQ10), a model water-insoluble compound, can be nanoparticulated into a water-soluble form using apolipoprotein A-I (apoA-I). Similar to the way that apoA-I forms nascent discoidal high density lipoprotein (ndHDL) particles by bordering acyl chain tails of phospholipids, CoQ10 could be enclosed into the circle of a disk made of apoA-Is. The resulting nanostructure of CoQ10 and apoA-I was water-soluble with a size of ∼12 nm in diameter and was physically more robust than liposome. We expect that the strategy suggested in this study can be exploited to assemble nano-sized, water-soluble structures of various water-insoluble drug candidates.  相似文献   
119.
This paper continues the publication of newly obtained results from a continuing taxonomic investigation of the genus Aspidistra in Laos and Vietnam. It includes illustrated diagnoses of two new species, A. melanaster Aver., K.S. Nguyen & Tillich, A. obliqua K.S. Nguyen & Aver., two new varieties, A. semiaperta Aver. & Tillich var. globulifera Aver., K.S. Nguyen & Tillich, A. lutea Tillich var. luteo-rubra K.S. Nguyen, Aver. & Tillich, and notes on two species, A. austroyunnanensis G.W. Hu, Lei Cai & Q.F. Wang and A. hekouensis H. Li, C.L. Long & Bogner newly recorded in the flora of Vietnam. Color illustrations, new or updated data on morphology, ecology, phenology, tentative relationships, distribution and conservation status are provided for all the mentioned taxa.  相似文献   
120.
Summary D-Amino acid oxidase (DAAO) genes were amplified from Trigonopsis variabilis and Rhodotorula gracilis by polymerase chain reactions. T. variabilis DAAO gene was cloned into a pUC19 vector. The expression of the T. variabilis DAAO was directly determined in permeabilized E. coli cells using a micro pO2 probe. The micro pO2 probe was sensitive enough to be suitable for a simple and rapid estimation of DAAO activity toward cephalosporin C.  相似文献   
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