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141.
Pelargonium sidoides is a medical herb and respective extracts are used very frequently for the treatment of respiratory tract infections. However, the effects of Pelargonium sidoides and a special extract prepared from its roots (EPs 7630) on human immune cells are not fully understood. Here we demonstrate that EPs 7630 induced a rapid and dose-dependent production of TNF-α, IL-6, and IL-10 by human blood immune cells. This EPs 7630-induced cytokine profile was more pro-inflammatory in comparison with the profile induced by viral or bacterial infection-mimicking agents. The search for EPs 7630 target cells revealed that T-cells did not respond to EPs 7630 stimulation by production of TNF-α, IL-6, or IL-10. Furthermore, pretreatment of T-cells with EPs 7630 did not modulate their TNF-α, IL-6, and IL-10 secretion during subsequent activation. In contrast to lymphocytes, monocytes showed clear intracellular TNF-α staining after EPs 7630 treatment. Accordingly, EPs 7630 predominantly provoked activation of MAP kinases and inhibition of p38 strongly reduced the monocyte TNF-α production. The pretreatment of blood immune cells with EPs 7630 lowered their secretion of TNF-α and IL-10 and caused an IL-6 dominant response during second stimulation with viral or bacterial infection-mimicking agents. In summary, we demonstrate that EPs 7630 activates human monocytes, induces MAP kinase-dependent pro-inflammatory cytokines in these cells, and specifically modulates their production capacity of mediators known to lead to an increase of acute phase protein production in the liver, neutrophil generation in the bone marrow, and the generation of adaptive Th17 and Th22 cells.  相似文献   
142.

Background

In the last two decades, chikungunya virus (CHIKV) has rapidly expanded to several geographical areas, causing frequent outbreaks in sub-Saharan Africa, South East Asia, South America, and Europe. Therefore, the disease remains heavily neglected in Mozambique, and no recent study has been conducted.

Methods

Between January and September 2013, acute febrile patients with no other evident cause of fever and attending a health center in a suburban area of Maputo city, Mozambique, were consecutively invited to participate. Paired acute and convalescent serum samples were requested from each participant. Convalescent samples were initially screened for anti-CHIKV IgG using a commercial indirect immunofluorescence test, and if positive, the corresponding acute sample was screened using the same test.

Results

Four hundred patients were enrolled. The median age of study participants was 26 years (IQR: 21–33 years) and 57.5% (224/391) were female. Paired blood samples were obtained from 209 patients, of which 26.4% (55/208) were presented anti-CHIKV IgG antibodies in the convalescent sample. Seroconversion or a four-fold titer rise was confirmed in 9 (4.3%) patients.

Conclusion

The results of this study strongly suggest that CHIKV is circulating in southern Mozambique. We recommend that CHIKV should be considered in the differential diagnosis of acute febrile illness in Mozambique and that systematic surveillance for CHIKV should be implemented.  相似文献   
143.
Death of oligodendrocytes accompanied by destruction of neurons and axons are typical histopathological findings in cortical and subcortical grey matter lesions in inflammatory demyelinating disorders like multiple sclerosis (MS). In these disorders, mainly CD8+ T-cells of putative specificity for myelin- and oligodendrocyte-related antigens are found, so that neuronal apoptosis in grey matter lesions may be a collateral effect of these cells. Different types of animal models are established to study the underlying mechanisms of the mentioned pathophysiological processes. However, although they mimic some aspects of MS, it is impossible to dissect the exact mechanism and time course of ‘‘collateral’’ neuronal cell death. To address this course, here we show a protocol to study the mechanisms and time response of neuronal damage following an oligodendrocyte-directed CD8+ T cell attack. To target only the myelin sheath and the oligodendrocytes, in vitro activated oligodendrocyte-specific CD8+ T-cells are transferred into acutely isolated brain slices. After a defined incubation period, myelin and neuronal damage can be analysed in different regions of interest. Potential applications and limitations of this model will be discussed.  相似文献   
144.
Inflammatory processes and metabolic alterations are supposed to substantially interact. Recently, cumulating reports describe a profound role of interleukin(IL)-22 in this relationship. IL-22 is a particular kind of immune mediator that is produced by certain lymphocyte populations and regulates the function of several tissue cells but not immune cells. So far, IL-22 was known to plays a fundamental role in the elimination of bacterial infections at border surfaces of the body and to protect tissues from damage. This research highlight article arranges the facts regarding the effects of IL-22 in the context of adiposity and metabolic alterations and postulates a new function of the immune system.  相似文献   
145.

Objectives

Severe pre-eclampsia and eclampsia are one of the major causes of maternal mortality globally. Reducing maternal morbidity and mortality demands optimizing quality of care. Criteria-based audits are a tool to define, assess and improve quality of care. The aim of this study was to determine applicability of a criteria-based audit to assess quality of care delivered to women with severe hypertensive disorders in pregnancy, and to assess adherence to protocols and quality of care provided at a regional hospital in Accra, Ghana.

Methods

Checklists for management of severe preeclampsia, hypertensive emergency and eclampsia were developed in an audit cycle based on nine existing key clinical care protocols. Fifty cases were audited to assess quality of care, defined as adherence to protocols. Analysis was stratified for complicated cases, defined as (imminent) eclampsia, perinatal mortality and/or one or more WHO maternal near miss C-criteria.

Results

Mean adherence to the nine protocols ranged from 15–85%. Protocols for ‘plan for delivery’ and ‘magnesium sulphate administration’ were best adhered to (85%), followed by adherence to protocols for ‘eclampsia’ (64%), ‘severe pre-eclampsia at admission’ (60%), ‘severe pre-eclampsia ward follow-up’ (53%) and ‘hypertensive emergency’ (53%). Protocols for monitoring were least adhered to (15%). No difference was observed for severe disease. Increased awareness, protocol-based training of staff, and clear task assignment were identified as contributors to better adherence.

Conclusion

A criteria-based audit is an effective tool to determine quality of care, identify gaps in standard of care, and allow for monitoring and evaluation in a health facility, ultimately resulting in improved quality of care provided and reduced maternal morbidity and mortality. In our audit, good adherence was observed for plan for delivery and treatment with magnesium sulphate. Substandard adherence to a number of protocols was identified, and points towards opportunities for targeted improvement strategies.  相似文献   
146.
The heart hosts tissue resident macrophages which are capable of modulating cardiac inflammation and function by multiple mechanisms. At present, the consequences of phenotypic diversity in macrophages in the heart are incompletely understood. The contribution of cardiac M2-polarized macrophages to the resolution of inflammation and repair response following myocardial infarction remains to be fully defined. In this study, the role of M2 macrophages was investigated utilising a specific CSF-1 receptor signalling inhibition strategy to achieve their depletion. In mice, oral administration of GW2580, a CSF-1R kinase inhibitor, induced significant decreases in Gr1lo and F4/80hi monocyte populations in the circulation and the spleen. GW2580 administration also induced a significant depletion of M2 macrophages in the heart after 1 week treatment as well as a reduction of cardiac arginase1 and CD206 gene expression indicative of M2 macrophage activity. In a murine myocardial infarction model, reduced M2 macrophage content was associated with increased M1-related gene expression (IL-6 and IL-1β), and decreased M2-related gene expression (Arginase1 and CD206) in the heart of GW2580-treated animals versus vehicle-treated controls. M2 depletion was also associated with a loss in left ventricular contractile function, infarct enlargement, decreased collagen staining and increased inflammatory cell infiltration into the infarct zone, specifically neutrophils and M1 macrophages. Taken together, these data indicate that CSF-1R signalling is critical for maintaining cardiac tissue resident M2-polarized macrophage population, which is required for the resolution of inflammation post myocardial infarction and, in turn, for preservation of ventricular function.  相似文献   
147.
Mimicking female insects to attract male pollinators is an important strategy in sexually deceptive orchids of the genus Ophrys, and some species possess flowers with conspicuous labellum patterns. The function of the variation of the patterns remains unresolved, with suggestions that these enhance pollinator communication. We investigated the possible function of the labellum pattern in Ophrys heldreichii, an orchid species in which the conspicuous and complex labellum pattern contrasts with a dark background. The orchid is pollinated exclusively by males of the solitary bee, Eucera berlandi. Comparisons of labellum patterns revealed that patterns within inflorescences are more similar than those of other conspecific plants. Field observations showed that the males approach at a great speed and directly land on flowers, but after an unsuccessful copulation attempt, bees hover close and visually scan the labellum pattern for up to a minute. Learning experiments conducted with honeybees as an accessible model of bee vision demonstrated that labellum patterns of different plants can be reliably learnt; in contrast, patterns of flowers from the same inflorescence could not be discriminated. These results support the hypothesis that variable labellum patterns in O. heldreichii are involved in flower-pollinator communication which would likely help these plants to avoid geitonogamy.  相似文献   
148.
In order to design potential biomaterials, we investigated the laccase-catalyzed cross-linking between l-lysine or lysine-containing peptides and dihydroxylated aromatics. l-Lysine is one of the major components of naturally occurring mussel adhesive proteins (MAPs). Dihydroxylated aromatics are structurally related to 3,4-dihydroxyphenyl-l-alanine, another main component of MAPs. Mass spectrometry and nuclear magnetic resonance analyses show that the ε-amino group of l-lysine is able to cross-link dihydroxylated aromatics. Additional oligomer and polymer cross-linked products were obtained from di- and oligopeptides containing l-lysine. Potential applications in medicine or industry for biomaterials synthesised via the three component system consisting of the oligopeptide [Tyr-Lys]10, dihydroxylated aromatics and laccase are discussed.  相似文献   
149.
Antagonists of the human histamine H3 receptor (hH3R) often contain a second basic moiety, which is well known to boost affinity on this histamine receptor subtype. Here, we prepared compounds with acidic moieties of different pKa values to figure out that the hH3R tolerates these functionalities when added to a common pharmacophore blueprint. Depending on the acidic, electronic and steric features the designed ligands showed hH3R affinities in the nanomolar concentration range. Additionally, selected ligands were tested but failed as dual acting hH3R/hPPAR (human peroxisome proliferator-activated receptor) ligands.  相似文献   
150.
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