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51.

Background and Purpose

The most common strategy for treating patients with acute ischemic stroke is thrombolytic therapy, though only a few patients receive benefits because of the narrow time window. Inflammation occurring in the central nervous system (CNS) in association with ischemia is caused by immune cells including monocytes and involved in lesion expansion. If the specific roles of monocyte subsets in stroke can be revealed, they may become an effective target for new treatment strategies.

Methods

We performed immunological examinations of 36 consecutive ischemic stroke patients within 2 days of onset and compared the results with 24 age-matched patients with degenerative disorders. The stroke patients were repeatedly tested for the proportions of monocyte subsets in blood, and serum levels of pro- and anti-inflammatory cytokines immediately after admission, on days 3-7 and 12-16 after stroke onset, and on the day of discharge. In addition, immunological measurements were analyzed for relationships to stroke subtypes and complications, including progressive infarction (PI) and stroke-associated infection (SAI).

Results

Monocyte count was significantly increased from 0–16 days after stroke as compared to the controls (p<0.05). CD14highCD16- classical and CD14highCD16+ intermediate monocytes were significantly increased from 0-7 and 3-16 days after stroke, respectively (p<0.05), whereas CD14 dimCD16high non-classical monocytes were decreased from 0–7 days (p<0.05). Cardioembolic infarction was associated with a persistent increase in intermediate monocytes. Furthermore, intermediate monocytes were significantly increased in patients with PI (p<0.05), while non-classical monocytes were decreased in those with SAI (p<0.05). IL-17A levels were positively correlated with monocyte count (r=0.485, p=0.012) as well as the percentage of non-classical monocytes (r=0.423, p=0.028), and negatively with that of classical monocytes (r=-0.51, p=0.007) during days 12-16.

Conclusions

Our findings suggest that CD14highCD16+ intermediate monocytes have a role in CNS tissue damage during acute and subacute phases in ischemic stroke especially in relation to cardioembolism.  相似文献   
52.
Animal populations are spatially structured in heterogeneous landscapes, in which local patches with differing vital rates are connected by dispersal of individuals to varying degrees. Although there is evidence that vital rates differ among local populations, much less is understood about how vital rates covary among local patches in spatially heterogeneous landscapes. In this study, we conducted a nine-year annual mark–recapture survey to characterize spatial covariation of survival and growth for two Japanese native salmonids, white-spotted charr Salvelinus leucomaenis japonicus and red-spotted masu salmon Oncorhynchus masou ishikawae, in a headwater stream network composed of distinctly different tributary and mainstem habitats. Spatial structure of survival and growth differed by species and age class, but results provided support for negative covariation between vital rates, where survival was higher in the tributary habitat but growth was higher in the mainstem habitat. Thus, neither habitat was apparently more important than the other, and local habitats with complementary vital rates may make this spatially structured population less vulnerable to environmental change (i.e. portfolio effect). Despite the spatial structure of vital rates and possibilities that fish can exploit spatially distributed resources, movement of fish was limited due partly to a series of low-head dams that prevented upstream movement of fish in the study area. This study shows that spatial structure of vital rates can be complex and depend on species and age class, and this knowledge is likely paramount to elucidating dynamics of spatially structured populations.  相似文献   
53.

Background

There is not much information on established standard therapy for patients with severe methionine adenosyltransferase (MAT) I/III deficiency.

Case presentation

We report a boy with MAT I/III deficiency, in whom plasma methionine and total homocysteine, and urinary homocystine were elevated. Molecular genetic studies showed him to have novel compound heterozygous mutations of the MAT1A gene: c.191T>A (p.M64K) and c.589delC (p.P197LfsX26). A low methionine milk diet was started at 31 days of age, and during continuing dietary methionine restriction plasma methionine levels have been maintained at less than 750 μmol/L. He is now 5 years old, and has had entirely normal physical growth and psychomotor development.

Conclusions

Although some severely MAT I/III deficient patients have developed neurologic abnormalities, we report here the case of a boy who has remained neurologically and otherwise normal for 5 years during methionine restriction, suggesting that perhaps such management, started in early infancy, may help prevent neurological complications.  相似文献   
54.
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   
55.
Nascent chain release from membrane-bound ribosomes by the termination codon was investigated using a cell-free translation system from rabbit supplemented with rough microsomal membrane vesicles. Chain release was extremely slow when mRNA ended with only the termination codon. Tail extension after the termination codon enhanced the release of the nascent chain. Release reached plateau levels with tail extension of 10 bases. This requirement was observed with all termination codons: TAA, TGA and TAG. Rapid release was also achieved by puromycin even in the absence of the extension. Efficient translation termination cannot be achieved in the presence of only a termination codon on the mRNA. Tail extension might be required for correct positioning of the termination codon in the ribosome and/or efficient recognition by release factors.  相似文献   
56.
(?)-6-(7-Methoxy-2-(trifluoromethyl)pyrazolo[1,5-a]pyridin-4-yl)-5-methyl-4,5-dihydropyridazin-3(2H)-one (KCA-1490) exhibits moderate dual PDE3/4-inhibitory activity and promises as a combined bronchodilatory/anti-inflammatory agent. N-alkylation of the pyridazinone ring markedly enhances potency against PDE4 but suppresses PDE3 inhibition. Addition of a 6-aryl-4,5-dihydropyridazin-3(2H)-one extension to the N-alkyl group facilitates both enhancement of PDE4-inhibitory activity and restoration of potent PDE3 inhibition. Both dihydropyridazinone rings, in the core and extension, can be replaced by achiral 4,4-dimethylpyrazolone subunits and the core pyrazolopyridine by isosteric bicyclic heteroaromatics. In combination, these modifications afford potent dual PDE3/4 inhibitors that suppress histamine-induced bronchoconstriction in vivo and exhibit promising anti-inflammatory activity via intratracheal administration.  相似文献   
57.
Three new polyketides, manzamenones L–N (13), have been isolated from an Okinawan marine sponge of the genus Plakortis. The structures of 13 were elucidated on the basis of spectroscopic data. Manzamenones L–N (13) were new dimeric fatty-acid derivatives consisting of a tetrahydroindenone with three carboxy groups and two hexadecanyl chains. Manzamenones M (2) and N (3) showed antimicrobial activity against several bacteria and fungi.  相似文献   
58.
We previously identified KCA-1490 [(?)-6-(7-methoxy-2-trifluoromethyl-pyrazolo[1,5-a]pyridin-4-yl)-5-methyl-4,5-dihydro-3-(2H)-pyridazinone], a dual PDE3/4 inhibitor. In the present study, we found highly potent selective PDE4 inhibitors derived from the structure of KCA-1490. Among them, N-(3,5-dichloropyridin-4-yl)-7-methoxy-2-(trifluoromethyl)pyrazolo[1,5-a]pyridine-4-carboxamide (2a) had good anti-inflammatory effects in an animal model.  相似文献   
59.
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60.
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