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91.
Patients with severe COPD are known to have comorbidities such as emaciation, cor pulmonale and right heart failure, muscle weakness, hyperlipemia, diabetes mellitus, osteoporosis, muscle atrophy, arterial sclerosis, hypertension, and depression. Therefore, treatment for COPD needs to focus on these comorbidities as well as the lungs. We previously reported a new mouse model of COPD utilizing the human surfactant protein C promoter SP-C to drive the expression of mature mouse IL-18 cDNA; constitutive IL-18 overproduction in the lungs of transgenic (Tg) mice induces severe emphysematous change, dilatation of the right ventricle, and mild pulmonary hypertension with aging. In the present study, we evaluated the progression of comorbidity in our COPD model. In female Tg mice, significant weight loss was observed at 16 weeks and beyond, when compared with control wild-type (WT) mice. This weight loss was suppressed in IL-13-deficient (knockout; KO) Tg mice. Muscle weight and bone mineral density were significantly decreased in aged Tg mice relative to control WT and IL-13 KO Tg mice. The aged Tg mice also showed impaired glucose tolerance. IL-18 and IL-13 may play important roles in the pathogenesis of comorbidity in COPD patients.  相似文献   
92.
Adenosine triphosphate (ATP) turnover drives various processive molecular motors and adenosine diphosphate (ADP) release is a principal transition in this cycle. Biochemical and single molecule mechanical studies have led to a model in which a slow ADP release step contributes to the processivity of myosin-V. To test the relationship between force generation and ADP release, we utilized optical trapping nanometry and single molecule total internal reflection fluorescence imaging for simultaneous and direct observation of both processes in myosin-V. We found that ADP was released 69 ± 5.3 ms after force generation and displacement of actin, providing direct evidence for slow ADP release. As proposed by several previous studies, this slow ADP release probably ensures processivity by prolonging the strong actomyosin state in the ATP turnover cycle.  相似文献   
93.
94.
Amino acid sequence and the location of three glycopeptides of the Fc fragment obtained by limited proteolysis with trypsin of an intact myeloma protein(NIG-65) has been determined. These glycopeptides have glucosamine oligosaccharides(designated GlcN) which are attached to Asn-68, Asn-159, and Asn-210 by N-glycosidic linkages. Of these, Glcn-159 is characteristic of the δ chain and has no counterpart position in any of the other classes. On the other hand, GlcN-68 is shared by γ, μ, and ? chains, and GlcN-210 by α and μ chains, respectively. Although different classes of human immunoglobulins differ in the number and the kinds of oligosaccharides, the sites are often homologous and are related to the basic immunoglobulin domain structure.  相似文献   
95.
Seven kinds of asparagine-linked oligosaccharides were bound to the Fc region of a human immunoglobulin D(NIG-65). The oligosaccharides quantitatively released from four species of glycopeptides by digestion with almond glycopeptidase, were separated by Bio-Gel p-4 column chromatography and were purified further by thin-layer chromatography. The sugars were identified with GC-MS following the permethylation of respective oligosaccharide. To Asn-68(NIG-65 Fc numbering (1)), two kinds of high-mannose-type oligosaccharides were bonded. To Asn-159, a kind of hybride-type and two kinds of bisected complex-type oligosaccharides were attached. From Asn-210, four kinds of bisected complex-type oligosaccharides were isolated.  相似文献   
96.
In order to develop a new positron emission tomography (PET) probe to study hepatobiliary transport mediated by the multi-drug and toxin extrusion transporter 1 (MATE1), 11C-labelled metformin was synthesized and then evaluated as a PET probe. [11C]Metformin ([11C]4) was synthesized in three steps, from [11C]methyl iodide. Evaluation by small animal PET of [11C]4 showed that there was increased concentrations of [11C]4 in the livers of mice pre-treated with pyrimethamine, a potential inhibitor of MATEs, inhibiting the hepatobiliary excretion of metformin. Radiometabolite analysis showed that [11C]4 was not degraded in vivo during the PET scan. Biodistribution studies were undertaken and the organ distributions were extrapolated into a standard human model. In conclusion, [11C]4 may be useful as a PET probe to non-invasively study the in vivo function of hepatobiliary transport and drug–drug interactions, mediated by MATE1 in future clinical investigations.  相似文献   
97.
A sequencing batch reactor under different electron acceptor conditions was operated serially to investigate the selection and dominance mechanisms of denitrifying phosphate-accumulating organisms (DNPAOs) in a biological nutrient removal process. The presence of a small amount of NO 3 at the start of the anaerobic phase stimulated the selection of DNPAOs in an anaerobic/aerobic system, and switching O2 to NO 3 as an electron acceptor enhanced the activity of anoxic phosphate uptake.  相似文献   
98.
A key common feature of all but three known mammalian genera is the strict seven cervical vertebrae blueprint, suggesting the involvement of strong conserving selection forces during mammalian radiation. This is further supported by reports indicating that children with cervical ribs die before they reach reproductive age. Hypotheses were put up, associating cervical ribs (homeotic transformations) to embryonal cancer (e.g., neuroblastoma) or ascribing the constraint in cervical vertebral count to the development of the mammalian diaphragm. Here, we describe a spontaneous mutation c.196A > G in the Bos taurus T gene (also known as brachyury) associated with a cervical vertebral homeotic transformation that violates the fundamental mammalian cervical blueprint, but does not preclude reproduction of the affected individual. Genome-wide mapping, haplotype tracking within a large pedigree, resequencing of target genome regions, and bioinformatic analyses unambiguously confirmed the mutant c.196G allele as causal for this previously unknown defect termed vertebral and spinal dysplasia (VSD) by providing evidence for the mutation event. The nonsynonymous VSD mutation is located within the highly conserved T box of the T gene, which plays a fundamental role in eumetazoan body organization and vertebral development. To our knowledge, VSD is the first unequivocally approved spontaneous mutation decreasing cervical vertebrae number in a large mammal. The spontaneous VSD mutation in the bovine T gene is the first in vivo evidence for the hypothesis that the T protein is directly involved in the maintenance of the mammalian seven-cervical vertebra blueprint. It therefore furthers our knowledge of the T-protein function and early mammalian notochord development.  相似文献   
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