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111.
112.
Summary The aggregation of leucocytes provoked in the peritoneal cavity of the white mouse by intraperitoneal injection of livingE. coli is inhibited by large doses of hydrocortisone. At the same time, the animal's susceptibility to infection is enhanced. The aggregation of leucocytes induced by injection of a bacterial extract containing lipopolysaccharides is inhibited in a similar manner. The effect of hydrocortisone sets in rapidly and subsides within 24 h. The inhibitory effect of hydrocortisone on the lipopolysaccharid effect on leucocytes seems to be an important factor in the influence of hydrocortisone on the infectious process.  相似文献   
113.
Summary A computer-aided arrangement was used to study the time function of lactate output of isolated intestinal epithelial cells in an open system. The results indicate better viability of the cells than in a closed system.Supported by grant no. 2134 of the Austrian Fonds zur Förderung der wissenschaftlichen Forschung.  相似文献   
114.
SPARC is a matricellular protein, able to modulate cell/ECM interactions and influence cell responses to growth factors, and therefore is particularly attuned to contribute to physiological processes involving changes in ECM and cell mobilization. Indeed, the list of biological processes affected by SPARC includes wound healing, tumor progression, bone formation, fibrosis, and angiogenesis. The process of angiogenesis is complex and involves a number of cellular processes such as endothelial cell proliferation, migration, ECM degradation, and synthesis, as well as pericyte recruitment to stabilize nascent vessels. In this review, we will summarize current results that explore the function of SPARC in the regulation of angiogenic events with a particular emphasis on the modulation of growth factor activity by SPARC in the context of blood vessel formation. The primary function of SPARC in angiogenesis remains unclear, as SPARC activity in some circumstances promotes angiogenesis and in others is more consistent with an anti-angiogenic activity. Undoubtedly, the mercurial nature of SPARC belies a redundancy of functional proteins in angiogenesis as well as cell-type-specific activities that alter signal transduction events in response to unique cellular milieus. Nonetheless, the investigation of cellular mechanisms that define functional activities of SPARC continue to contribute novel and exciting paradigms to vascular biology.  相似文献   
115.

Objective

Extracellular vesicles (EVs) are subcellular signalosomes. Although characteristic EV production is associated with numerous physiological and pathological conditions, the effect of blood-derived EVs on bone homeostasis is unknown. Herein we evaluated the role of circulating EVs on human osteoclastogenesis.

Methods

Blood samples from healthy volunteers, rheumatoid arthritis (RA) and psoriatic arthritis (PsA) patients were collected. Size-based EV sub-fractions were isolated by gravity-driven filtration and differential centrifugation. To investigate the properties of EV samples, resistive pulse sensing technique, transmission electron microscopy, flow cytometry and western blot were performed. CD14+ monocytes were separated from PBMCs, and stimulated with recombinant human M-CSF, RANKL and blood-derived EV sub-fractions. After 7 days, the cells were fixed and stained for tartrate-resistant acid phosphatase and counted.

Results

EVs isolated by size-based sub-fractions were characterized as either microvesicles or exosomes (EXO). Healthy (n = 11) and RA-derived (n = 12) EXOs profoundly inhibited osteoclast differentiation (70%, p < 0.01; 65%, p < 0.01, respectively). In contrast, PsA-derived (n = 10) EXOs had a stimulatory effect (75%, p < 0.05). In cross-treatment experiments where EXOs and CD14+ cells were interchanged between the three groups, only healthy (n = 5) and RA (n = 5)-derived EXOs inhibited (p < 0.01, respectively) the generation of osteoclasts in all groups, whereas PsA (n = 7)-derived EXOs were unable to mediate this effect.

Conclusions

Our data suggest that blood-derived EXOs are novel regulators of the human osteoclastogenesis and may offer discrete effector function in distinct inflammatory arthropathies.
  相似文献   
116.
Receptor for advanced glycation end products (RAGE) mediates diverse physiological and pathological effects and is involved in the pathogenesis of Alzheimer’s disease (AD). RAGE is a receptor for amyloid β peptides (Aβ), mediates Aβ neurotoxicity and also promotes Aβ influx into the brain and contributes to Aβ aggregation. Soluble RAGE (sRAGE), a secreted RAGE isoform, acts as a decoy receptor to antagonize RAGE-mediated damages. Accumulating evidence has suggested that sRAGE represents a promising pharmaceutic against RAGE-mediated disorders. Recent studies revealed proteolysis of RAGE as a previously unappreciated means of sRAGE production. In this review we summarize these findings on the proteolytic cleavage of RAGE and discuss the underlying regulatory mechanisms of RAGE shedding. Furthermore, we propose a model in which proteolysis of RAGE could restrain AD development by reducing Aβ transport into the brain and Aβ production via BACE. Thus, the modulation of RAGE proteolysis provides a novel intervention strategy for AD.  相似文献   
117.
118.
Summary Serotonin was determined in platelets of 47 patients with alcoholism during the state of withdrawal as well as in a group of healthy persons. The results show that serotonin values were significantly lower in the group of patients with alcoholism as compared with the control group of healthy persons.  相似文献   
119.
Summary Different purified polysaccharides, mucopolysaccharides, phosphatides and carbohydrat-sulfonic acids have been investigated for their effect on stimulation of leucocytic migrationin vitro. The bacterial polysaccharides of proteus,S. marcescens, shiga and shiga fullantigen, have been found to be of high specific activity. All other compounds have much less or no activity. Therefore it might be concluded that the type of bacterial polysaccharides which promote leucocytic migration belong to a highly specific group.  相似文献   
120.
Zusammenfassung Die hypotensiven Wirkungen von Hydralazin und Guanethidin an renal hypertonischen Ratten konnten für kurze Zeit durch Pronethalol antagonisiert werden. Die Wirkung von-Methyl-DOPA wurde nicht beeinflusst.  相似文献   
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