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81.
The phylogenetic affiliation and physiological characteristics (e.g., Ks and maximum specific growth rate [μmax]) of an anaerobic ammonium oxidation (anammox) bacterium, “Candidatus Scalindua sp.,” enriched from the marine sediment of Hiroshima Bay, Japan, were investigated. “Candidatus Scalindua sp.” exhibits higher affinity for nitrite and a lower growth rate and yield than the known anammox species.  相似文献   
82.
83.
Adipose tissue‐derived mesenchymal stem cells (ADSCs) are multipotent and can differentiate into various cell types, including osteocytes, adipocytes, neural cells, vascular endothelial cells, cardiomyocytes, pancreatic β‐cells, and hepatocytes. Compared with the extraction of other stem cells such as bone marrow‐derived mesenchymal stem cells (BMSCs), that of ADSCs requires minimally invasive techniques. In the field of regenerative medicine, the use of autologous cells is preferable to embryonic stem cells or induced pluripotent stem cells. Therefore, ADSCs are a useful resource for drug screening and regenerative medicine. Here we present the methods and mechanisms underlying the induction of multilineage cells from ADSCs.  相似文献   
84.
“Nagashima-type” palmoplantar keratosis (NPPK) is an autosomal recessive nonsyndromic diffuse palmoplantar keratosis characterized by well-demarcated diffuse hyperkeratosis with redness, expanding on to the dorsal surfaces of the palms and feet and the Achilles tendon area. Hyperkeratosis in NPPK is mild and nonprogressive, differentiating NPPK clinically from Mal de Meleda. We performed whole-exome and/or Sanger sequencing analyses of 13 unrelated NPPK individuals and identified biallelic putative loss-of-function mutations in SERPINB7, which encodes a cytoplasmic member of the serine protease inhibitor superfamily. We identified a major causative mutation of c.796C>T (p.Arg266) as a founder mutation in Japanese and Chinese populations. SERPINB7 was specifically present in the cytoplasm of the stratum granulosum and the stratum corneum (SC) of the epidermis. All of the identified mutants are predicted to cause premature termination upstream of the reactive site, which inhibits the proteases, suggesting a complete loss of the protease inhibitory activity of SERPINB7 in NPPK skin. On exposure of NPPK lesional skin to water, we observed a whitish spongy change in the SC, suggesting enhanced water permeation into the SC due to overactivation of proteases and a resultant loss of integrity of the SC structure. These findings provide an important framework for developing pathogenesis-based therapies for NPPK.  相似文献   
85.
The effects of substituting l-deoxynucleotide for d-deoxynucleotide at duplex termini were evaluated and the terminal substitutions were found to show much less effects on duplex destabilization and to show a similar tendency in base pairing selectivity, compared with internal chiral substitutions.  相似文献   
86.
To improve the efficacy of the conformationally restricted BACE1 inhibitors, structural modifications were investigated using two strategies: (a) modification of the terminal aromatic ring and (b) insertion of a spacer between the aromatic rings. In the latter approach, another type of inhibitor 17 bearing an ethylene spacer between two aromatic rings was found to exhibit good BACE1 inhibitory activity, while the corresponding conformationally unrestricted compound 25 showed no activity. This result revealed an interesting effect of a conformational restriction with a cyclopropane ring.  相似文献   
87.
In order to elucidate the structure-activity relationship of griseofulvin (1), (±)-6′-demethyl analog (3), 2′-demethoxy-6′-demethyldihydro analog (4), (±)-dechloro-6′-ethyl analog (5), (±)-dechloro-6′-epi-ethyl analog (6), (±)-6′-ethyl analog (7) and (±)-6′-epi-ethyl analog (8) were synthesized by a Diels-Alder cycloaddition of alkylidene ketones (16, 17, 18, 19 and 20) with modified 1,3-butadienes (21 or 22). Their biological activities were examined against fungi.  相似文献   
88.
The chorismate mutase and prephenate dehydratase genes of phenylalanine producing Corynebacterium glutamicum K38, which is resistant to p-fluorophenylalanine and m-fluorophenylalanine, were cloned into plasmid pCE53 in C. glutamicum KY9456, which lacks chorismate mutase and prephenate dehydratase. One of the resultant plasmids, pCmB4, contained a 9.4kb BamHI DNA fragment inserted into the unique BamHl site of pCE53. Plasmid pCmB4 complemented a phenylalanine and tyrosine double auxotroph of C. glutamicum KY9456. Introduction of pCmB4 into C. glutamicum RRL5 resulted in an about ten times increase in chorismate mutase activity. C. glutamicum K38 carrying the plasmid accumulated 19.0mg/ml of phenylalanine (50% increase over the yield of K38).  相似文献   
89.
Many rate-related phenomena occur in food manufacturing processes. This review addresses four of them, all of which are topics that the author has studied in order to design food manufacturing processes that are favorable from the standpoint of food engineering. They include chromatographic separation through continuous separation with a simulated moving adsorber, lipid oxidation kinetics in emulsions and microencapsulated systems, kinetic analysis and extraction in subcritical water, and water migration in pasta.  相似文献   
90.

Background

The association of complement with the progression of acute T cell mediated rejection (ATCMR) is not well understood. We investigated the production of complement components and the expression of complement regulatory proteins (Cregs) in acute T-cell mediated rejection using rat and human renal allografts.

Methods

We prepared rat allograft and syngeneic graft models of renal transplantation. The expression of Complement components and Cregs was assessed in the rat grafts using quantitative real-time PCR (qRT-PCR) and immunofluorescent staining. We also administered anti-Crry and anti-CD59 antibodies to the rat allograft model. Further, we assessed the relationship between the expression of membrane cofactor protein (MCP) by immunohistochemical staining in human renal grafts and their clinical course.

Results

qRT-PCR results showed that the expression of Cregs, CD59 and rodent-specific complement regulator complement receptor 1-related gene/protein-y (Crry), was diminished in the rat allograft model especially on day 5 after transplantation in comparison with the syngeneic model. In contrast, the expression of complement components and receptors: C3, C3a receptor, C5a receptor, Factor B, C9, C1q, was increased, but not the expression of C4 and C5, indicating a possible activation of the alternative pathway. When anti-Crry and anti-CD59 mAbs were administered to the allograft, the survival period for each group was shortened. In the human ATCMR cases, the group with higher MCP expression in the grafts showed improved serum creatinine levels after the ATCMR treatment as well as a better 5-year graft survival rate.

Conclusions

We conclude that the expression of Cregs in allografts is connected with ATCMR. Our results suggest that controlling complement activation in renal grafts can be a new strategy for the treatment of ATCMR.  相似文献   
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