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111.
Integra dermal regeneration template (Integra Life Sciences, Plainsboro, N.J.) is an effective treatment for full-thickness burns. It can also be useful in contracture release procedures; however, the clinical utility of a dermal regeneration template in contracture release procedures has not been adequately characterized. In this multicenter investigation, the outcomes of release procedures incorporating a dermal regeneration template for 89 consecutive patients, who underwent a total of 127 contracture releases, were retrospectively evaluated. The procedures involved the application of Integra, which includes a temporary silicone epidermal substitute and an artificial dermal layer. After formation of a neodermis, the silicone layer is removed and replaced with an epidermal autograft. Data on patient and contracture site history, treatment methods, physician assessments of range of motion or function, patient satisfaction, recurrence, and adverse events were collected with a standardized questionnaire. Release procedures for the study patients involved the neck, axilla, trunk, elbow, knee, hand, and other anatomical sites. The mean postoperative follow-up period was 11.4 months. At 76 percent of the release sites, range of motion or function was rated as good (significant improvement in range of motion or function) or excellent (maximal range of motion or function possible) by physicians. Responding patients expressed satisfaction with the overall results of treatment at 82 percent of the sites. No recurrence of contracture at 75 percent of the sites was observed during follow-up monitoring. Patient age and prior surgical treatment at the site did not significantly affect the results of treatment. However, outcomes were superior at mature sites, i.e., those for which more than 12 months had elapsed since the original injury. Postoperative complications rarely necessitated regrafting. These results indicate that a dermal regeneration template provides a useful alternative technique for contracture release procedures. The study data indicate that this approach leads to favorable functional outcomes and a high rate of patient satisfaction. This modality also seems to be versatile, because a range of anatomical sites are amenable to treatment with a dermal regeneration template, regardless of prior surgical treatment, and both pediatric and adult patients respond well to this form of therapy. Furthermore, Integra confers functional and cosmetic benefits similar to those of full-thickness grafts but without comparable potential for donor-site morbidity.  相似文献   
112.
Phenotypic variability for resistance against non-parasitic leaf spots (NPLS) has been observed between varieties. For the genetic characterization of NPLS resistance, a population with 430 doubled haploid (DH) lines was developed from the cross between the NPLS-resistant Hordeum vulgare breeding line IPZ24727 and the NPLS-sensitive barley cultivar Barke. A molecular map was constructed based on 164 AFLPs, 30 SSRs and one STS marker derived from the mlo gene. Field trials were performed over four environments in which NPLS and other agronomic traits were assessed. Estimates of genotypic variance were highly significant for NPLS. Moreover, no transgression was found for the trait. Quantitative trait loci (QTLs) for NPLS resistance were mapped in the DH population on chromosomes 1H, 4H, and 7H, with the most important effect on chromosome 4H. The QTLs for NPLS explained together 39% of the phenotypic and 49% of the genotypic variance, thereby showing additive gene action. Consequently, marker-assisted selection for improving NPLS resistance is possible.Communicated by H.F. Linskens  相似文献   
113.
Efficient gene transfer into murine embryonic stem cells by nucleofection   总被引:3,自引:0,他引:3  
Genetic manipulation of embryonic stem (ES) cells is performed by non-viral as well as viral transfection methods. We tested the recently developed nucleofection method delivering plasmid DNA directly into the nucleus for the introduction of a plasmid encoding enhanced green fluorescent protein (EGFP) into murine ES cells. Cell viability decreased from 77% before to 40% 24 h after nucleofection. Transfection effciencies in viable stem cells were between 85% and 96% with high levels of EGFP expression [mean fluorescence intensity (MFI): 630 +/- 90] 24 h after nucleofection. After a two week culture in geneticin (G418) selection medium, nearly 50% of the stem cells were EGFP positive and continued transgene expression (MFIs: 120-240) for a two further weeks. We conclude that nucleofection is an efficient nonviral gene transfer method for the introduction of genes into murine ES cells.  相似文献   
114.
A series of novel, highly potent, achiral factor Xa inhibitors based on a benzoic acid scaffold and containing a chlorophenethyl moiety directed towards the protease S1 pocket is described. A number of structural features, such as the requirements of the P1, P4 and ester-binding pocket ligands were explored with respect to inhibition of factor Xa. Compound 46 was found to be the most potent compound in a series of antithrombotic secondary assays.  相似文献   
115.
A series of novel, highly potent 2-carboxyindole-based factor Xa inhibitors is described. Structural requirements for neutral ligands, which bind in the S1 pocket of factor Xa were investigated with the 2-carboxyindole scaffold. This privileged fragment assembly approach yielded a set of equipotent, selective inhibitors with structurally diverse neutral P1 substituents.  相似文献   
116.
Pathogen recognition and signal transduction during plant pathogenesis is essential for the activation of plant defense mechanisms. To facilitate easy access to published data and to permit comparative studies of different pathogen response pathways, a database is indispensable to give a broad overview of the components and reactions so far known. PathoPlant has been developed as a relational database to display relevant components and reactions involved in signal transduction related to plant-pathogen interactions. On the organism level, the tables 'plant', 'pathogen' and 'interaction' are used to describe incompatible interactions between plants and pathogens or diseases. On the molecular level, plant pathogenesis related information is organized in PathoPlant's main tables 'molecule', 'reaction' and 'location'. Signal transduction pathways are modeled as consecutive sequences of known molecules and corresponding reactions. PathoPlant entries are linked to associated internal records as well as to entries in external databases such as SWISS-PROT, GenBank, PubMed, and TRANSFAC. PathoPlant is available as a web-based service at http://www.pathoplant.de.  相似文献   
117.
Mycoplasma haemocanis (formerly Haemobartonella canis) is a red blood cell parasite that causes disease mainly in immunosuppressed and splenectomized dogs. Clinical outbreak of the disease resulted in failure of a large experimental project. We aimed to identify whether M. haemocanis has increased prevalence in kennel-raised dogs. In a prospective study, we compared the prevalence of M. haemocanis in whole blood (anti-coagulated by use of EDTA) collected from pet dogs (University of Illinois, Urbana Champaign, Ill.; n = 60) with that in blood from dogs raised in three distinct kennels in western Europe (WE; n = 23), eastern Europe (EE; n = 20), and North America (NA; n = 20). Screening included antibody testing and microscopy of blood smears. The presence of M. haemocanis was identified using a polymerase chain reaction (PCR) assay for specific DNA of the organism. None of the pet dogs (0%) was test positive for M. haemocanis DNA. Mycoplasma haemocanis was found in dogs tested at all of the kennels. Infection rate in the three kennels was 30, 35, and 87%, respectively (all P < 0.001 versus control, chi2-test). Latent infection with M. haemocanis was not a single observation in kennel-raised dogs. Prevalence may be higher than that in a pet dog population. The potential exists for these latent infections to adversely affect or confound research results.  相似文献   
118.
Noncoding regulatory RNAs database   总被引:11,自引:2,他引:9  
  相似文献   
119.
Transmission electron microscopy was used to examine the ultrastructure of the allantoplacenta of garter snakes during the last half of gestation. This placenta occupies the dorsal hemisphere of the egg and is formed through apposition of the chorioallantois to the inner lining of the uterus. The uterine epithelium consists of flattened cells with short, irregular microvilli and others that bear cilia. The lamina propria is vascularized and its capillaries lie at the base of the uterine epithelial cells. The chorionic epithelium consists of a bilayer of squamous cells that are particularly thin superficial to the allantoic capillaries. Neither the chorionic epithelium nor the uterine epithelium undergoes erosion during development. Although a thin remnant of the shell membrane intervenes between fetal and maternal tissue at mid-gestation, it undergoes fragmentation by the end of gestation. Thus, uterine and chorionic epithelial are directly apposed in some regions of the allantoplacenta, forming continuous cellular boundaries at the placental interface. During development, capillaries proliferate in both the uterine and chorioallantoic tissues. By late gestation, the interhemal diffusion distance has thinned in some areas to less than 2 microm through attenuation of the uterine and chorionic epithelia. Morphologically, the allantoplacenta is well adapted for its function in gas exchange. However, the presence of cytoplasmic vesicles, ribosomal ER, and mitochondria in the chorionic and uterine epithelial cells are consistent with the possibility of additional forms of placental exchange.  相似文献   
120.
We present the construction of a synthetic library based on the scaffold of bovine heart fatty acid-binding protein (FABP) with 1.1x10(14) independent members. Ribosome display was applied to select streptavidin-binding peptides in vitro from 2x10(13) molecules of the library each encoding FABP with 15 contiguous random amino acid residues at its N terminus. The selection yielded several different binding peptides. The best binder possessed a dissociation constant as low as 4nM and, in contrast to the previously isolated peptides, contained no HPQ motif. A substitution analysis enabled shortening of the 15-mer peptide and revealed a 9-mer variant with a dissociation constant of 17nM, which is a 1000-fold increase of affinity compared to the already known peptides of this size. This high-affinity binding peptide in combination with the whole set of streptavidin conjugates should be an extremely useful tool for the detection and purification of recombinant proteins.  相似文献   
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