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101.
Çinar  Melih Ertan  Katagan  Tuncer  Ergen  Zeki  Sezgin  Murat 《Hydrobiologia》2002,472(1-3):107-117
The cavities and outer surfaces of 20 individuals of the sponge Sarcotragus muscarum collected from the Turkish Aegean coast during July–September 1993 contained a total of 148 zoobenthic species with 5299 individuals belonging to seven taxonomic groups. Among these, Polychaeta accounted for 60% of the total number of species, while Crustacea comprised 71% of the total number of individuals and 40% of the wet weight of biomass. The amphipod and decapod crustaceans Tritaeta gibbosa and Synalpheus gambarelloides, and the bivalve Hiatella arctica, were the most abundant species on the sponge samples both in terms of number of individuals and biomass values. The community structure inside the sponges was greatly influenced by the nature of the substratum around the sponge, and by the overwhelming population of the Lessepsian echinoderm Ophiactis savignyi. Number of species, biomass and diversity index values were found to be positively related to the sponge volume. Mean density and biomass of the associated taxa are 0.22 ind cm–3 and 11.63 mg cm–3, respectively.  相似文献   
102.
Both healthy and cancerous breast tissue is heterogeneous, which is a bottleneck for proteomics‐based biomarker analysis, as it obscures the cellular origin of a measured protein. We therefore aimed at obtaining a protein‐level interpretation of malignant transformation through global proteome analysis of a variety of laser capture microdissected cells originating from benign and malignant breast tissues. We compared proteomic differences between these tissues, both from cells of epithelial origin and the stromal environment, and performed string analysis. Differences in protein abundances corresponded with several hallmarks of cancer, including loss of cell adhesion, transformation to a migratory phenotype, and enhanced energy metabolism. Furthermore, despite enriching for (tumor) epithelial cells, many changes to the extracellular matrix were detected in microdissected cells of epithelial origin. The stromal compartment was heterogeneous and richer in the number of fibroblast and immune cells in malignant sections, compared to benign tissue sections. Furthermore, stroma could be clearly divided into reactive and nonreactive based on extracellular matrix disassembly proteins. We conclude that proteomics analysis of both microdissected epithelium and stroma gives an additional layer of information and more detailed insight into malignant transformation.  相似文献   
103.
The angiotensin-converting enzyme (ACE) plays an important role not only in the regulation of vascular homeostasis but also in stimulation of hematopoiesis. We aimed to evaluate the association between insertion/deletion (I/D) polymorphism of the ACE gene and anemia at the time of the diagnosis. We enrolled 75 patients with non-small-cell lung cancer (NSCLC) and 85 age- and sex-matched healthy control participants. The I/D polymorphism of ACE was identified by using polymerase chain reaction from peripheral blood samples. Statistical analyses were performed with SPSS for Windows. The distributions of the ACE genotypes and alleles are similar in patients and in healthy participants (P=0.29 and P=0.08, respectively). In patients with NSCLC, 34 (45.3%) had anemia; of whom 3 (8.8%) had genotype II, 24 (70.6%) had genotype ID, and 7 (20.6%) had genotype DD (P=0.001). The patients with the II and ID genotypes had more frequent anemia at the time of the diagnosis (odds ratio = 6.02; P=0.001). Our findings suggest that I/D polymorphism of the ACE gene may influence the development of anemia in patients with NSCLC.  相似文献   
104.
Several genes encoding different cytokines may play crucial roles in host susceptibility to lung cancer, since cytokine production capacity varies among individuals and depends on cytokine gene polymorphisms. The association between cytokine gene polymorphisms with primary lung carcinoma was investigated. DNA samples were obtained from a Turkish population of 44 patients with primary lung cancer, and 59 healthy control subjects. All genotyping (IFN-gamma, TGF-beta1, TNF-alpha, IL-6 and IL-10) experiments were performed using sequence-specific primers (SSP)-PCR. When compared to the healthy controls, the frequencies of high/intermediate producing genotypes of IL-10 and low producing genotype of TNF-alpha were significantly more common in the patient group. It is noteworthy that lung cancer patients with the TGF-beta T/T genotype in codon 10 had statistically longer survival compared to those having the C/C genotype (Kaplan-Meier survival function test, log rank significance = 0.014). These results suggest that IL-10, TNF-alpha and TGF-beta1 gene polymorphisms may affect host susceptibility to lung cancer and the outcome of the patients.  相似文献   
105.
Resistance emergence to carbapenem antibiotics was studied in a rat-thigh abscess model. Abscesses were developed in three groups with a total of 15 P. aeruginosa strains (three rats per strain). Groups were assigned to imipenem or meropenem treatment while one was left antibiotic-free. Test strains were fully susceptible to these antibiotics and the "Mutant Preventing Concentrations" of imipenem and meropenem over these strains were comparable. Antibiotic serum levels, assessed by serum bioassay test, were similar among therats. After four days, rats (n=45) were sacrificed and carbapenem resistant mutants were selected on imipenem (4 mg/L) and meropenem (4 mg/L) supplemented agar plates. Resistant variants of three strains, from four abscesses, were detected; one in the meropenem group, two in the imipenem and one in the untreated group. The MICs of imipenem and meropenem for the mutants were increased fourfold times or even higher of their counterparts. Resistance emergence under antibiotic pressure in P. aeruginosa has been shown in various conditions. To our knowledge, however, resistance emergence in abscess and also the comparison of imipenem and meropenem in this regard has not been studied before.  相似文献   
106.
After birth, a dramatic increase in fatty acid oxidation occurs in the heart, which has been attributed to an increase in l-carnitine levels and a switch from the liver (L) to muscle (M) isoform of carnitine palmitoyltransferase (CPT)-1. However, because M-CPT-1 is more sensitive to inhibition by malonyl CoA, a potent endogenous regulator of fatty acid oxidation, a switch to the M-CPT-1 isoform should theoretically decrease fatty acid oxidation. Because of this discrepancy, we assessed the contributions of myocardial l-carnitine content and CPT-1 isoform expression and kinetics to the maturation of fatty acid oxidation in newborn rabbit hearts. Although fatty acid oxidation rates increased between 1 and 14 days after birth, myocardial l-carnitine concentrations did not increase. Changes in the expression of L-CPT-1 or M-CPT-1 mRNA after birth also did not parallel the increase in fatty acid oxidation. The K(m) of CPT-1 for carnitine and the IC(50) for malonyl CoA remained unchanged between 1 and 10 days after birth. However, malonyl CoA levels dramatically decreased, due in part to an increase in malonyl CoA decarboxylase activity. Our data suggest that a decrease in malonyl CoA control of CPT-1 is primarily responsible for the increase in fatty acid oxidation seen in the newborn heart.  相似文献   
107.
The structures of substituted (aminomethyl)lithium and (thiomethyl)lithium compounds have been examined. Geometric parameters, charge densities, bond orders, dipole moments and heats of formation for all the members of the two series of monomers and dimers of the units LiCN(R)2 and LiCSR where R=H, CH3(Me), C6H5(Ph) have been calculated. The structures of the three complex compounds containing the same units; [[Li(CH2SMe)(THF)]X], [Li2(CH2SPh)2(THF)4] and [Li2(CH2NPh2)2(THF)3] have also been modeled. Geometry optimizations have been performed with the semiempirical PM3 method. The molecular orbital calculations have been carried out by a self-consistent field method using the restricted Hartree-Fock formalism. Comparisons have been made with the corresponding properties of methyl lithium monomer and dimer. The results show that in all of the nitrogen-containing monomers, the C-Li bonds weaken and the Li-C-H(N) angles decrease due to the coordination of lithium with nitrogen. Substitution of hydrogen atoms by methyl or phenyl groups decreases the Li-N coordination. In the sulfur-containing compounds, sulfur behaves similarly to nitrogen but the changes are smaller because the 3p lone-pair orbital of sulfur is higher in energy than the 2p lone-pair of nitrogen. All the dimers of nitrogen/sulfur-containing methyl lithium derivatives form six-membered rings in which the Li-N(S) coordination is greater than the one in the corresponding monomers. Dimerization reactions have been found to be exothermic and the formation of all the dimers is favored. The results obtained for the three complex structures are comparable to the experimental results reported in the literature.Keywords:  相似文献   
108.
109.
The roles of lipopolysaccharides (LPS) and extracellular polymers (ECP) on the adhesion of Pseudomonas aeruginosa PAO1 (expresses the A-band and B-band of O antigen) and AK1401 (expresses the A-band but not the B-band) to silicon were investigated with atomic force microscopy (AFM) and related to biopolymer physical properties. Measurement of macroscopic properties showed that strain AK1401 is more negatively charged and slightly more hydrophobic than strain PAO1 is. Microscopic AFM investigations of individual bacteria showed differences in how the biopolymers interacted with silicon. PAO1 showed larger decay lengths in AFM approach cycles, suggesting that the longer polymers on PAO1 caused greater steric repulsion with the AFM tip. For both bacterial strains, the long-range interactions we observed (hundreds of nanometers) were inconsistent with the small sizes of LPS, suggesting that they were also influenced by ECP, especially polysaccharides. The AFM retraction profiles provide information on the adhesion strength of the biopolymers to silicon (Fadh). For AK1401, the adhesion forces were only slightly lower (Fadh = 0.51 nN compared to 0.56 nN for PAO1), but the adhesion events were concentrated over shorter distances. More than 90% of adhesion events for AK1401 were at distances of <600 nm, while >50% of adhesion events for PAO1 were at distances of >600 nm. The sizes of the observed molecules suggest that the adhesion of P. aeruginosa to silicon was controlled by ECP, in addition to LPS. Steric and electrostatic forces each contributed to the interfacial interactions between P. aeruginosa and the silicon surface.  相似文献   
110.
This study investigated the anti-inflammatory effects of caffeic acid phenethyl ester (CAPE), a natural bee-produced compound, and compared it with corticosteroids in the treatment of experimentally induced methicillin-resistant Staphylococcus epidermidis (MRSE) endophthalmitis in addition to intravitreal antibiotics. An experimental endophthalmitis model was produced in 24 New Zealand albino rabbits by unilateral intravitreal injection of 0.1 ml of 4.7 x 10(4) colony-forming units (CFU) methicillin-resistant S. epidermidis. The animals were then divided randomly into three treatment groups and a control group, group 1 (six rabbits), received only intravitreal vancomycin (1.0 mg/0.1 ml); group 2 (six rabbits), received both intravitreal vancomycin (1.0 mg/0.1 ml) and intravitreal dexamethasone (400 microg/0.1 ml) and group 3 (six rabbits), received both intravitreal vancomycin (1.0 mg/0.1 ml) and subtenon CAPE (10 mg/0.3 ml) after 24 h post-infection. No treatment was given to the control group. Treatment efficacy was assessed by clinical examination, vitreous culture and histopathology. There were no statististically significant differences between clinical scores of all groups in examinations at 24 and 48 h post-infection (p = 0.915 and p = 0.067 respectively), but in examinations at 72 h post-infection and after 7 days post-infection, although the clinical scores of treatment groups were not significantly different from each other, they were significantly lower than the control group (p < 0.05). The culture results of all groups were sterile. As a result, CAPE was found to be as effective as dexamethasone in reducing inflammation in the treatment of experimental MRSE endophthalmitis when used with antibiotics. More studies are needed to determine the optimal administration route and effective dosage of this compound.  相似文献   
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