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71.
BACKGROUND: Iron chelation therapy (ICT) with deferoxamine (DFO), the current standard for the treatment of iron overload in patients with transfusion-dependent disorders such as beta-thalassemia, requires regular subcutaneous or intravenous infusions. This can lead to reduced quality of life and poor adherence, resulting in increased morbidity and mortality in iron-overloaded patients with beta-thalassemia. Deferasirox is an orally administered iron chelator that has been approved for use in the United States, Switzerland, and other countries. OBJECTIVE: This analysis was conducted to compare patient-reported outcomes (PROs) during receipt of DFO infusions or once-daily oral therapy with deferasirox (ICL670). METHODS: PROs were prospectively evaluated as part of a randomized, Phase III study comparing the efficacy and safety profile of DFO 20 to 60 mg/kg per day with those of deferasirox 5 to 30 mg/kg per day in patients (age > or =2 years) with beta-thalassemia who were receiving regular transfusions and had a liver iron concentration of > or =2 mg/g dry weight. PRO questionnaires were completed by patients or a parent or legal guardian at baseline, week 4, week 24, and end of study (EOS). Patients assessed their level of satisfaction with study treatment (very satisfied, satisfied, neutral, dissatisfied, or very dissatisfied) and rated its convenience (very convenient, convenient, neutral, inconvenient, or very inconvenient). Time lost from normal activities due to ICT in the previous 4 weeks was recorded using a single global assessment. At week 4, patients who had previous experience with DFO were asked to indicate their preference for treatment (ICT received before the study, ICT received during the study, no preference, or no response) and the reason for that preference. At EOS, all patients were asked if they would be willing to continue using the ICT they had received during the study. All study analyses were performed in all patients who received at least 1 dose of study medication. RESULTS: Five hundred eighty-six patients (304 females, 282 males; age range, 2-53 years) received treatment with DFO (n = 290) or deferasirox (n = 296). Significantly more patients treated with deferasirox reported being very satisfied or satisfied with treatment compared with those treated with DFO (week 4: 92.0% vs 50.4%, respectively; week 24: 89.6% vs 44.0%; EOS: 85.1% vs 38.7%; all, P < 0.001). At the same time points, the majority of those treated with deferasirox reported that treatment was very convenient or convenient compared with those treated with DFO (95.5% vs 21.3%, 91.7% vs 17.4%, and 92.7% vs 11.3%, respectively; all, P < 0.001). Among patients who had previously taken DFO and were randomized to receive deferasirox during the study, 96.9% reported a preference for deferasirox over DFO. At EOS, the proportion of patients indicating a willingness to continue study therapy was significantly greater in those receiving deferasirox than in those receiving DFO (85.8% vs 13.8%; P < 0.001). CONCLUSIONS: In this study, patient-reported satisfaction and convenience were significantly higher for the once-daily, oral ICT deferasirox than for DFO infusions. Among patients who had received DFO before the study, the majority indicated a preference for deferasirox over DFO. Most patients receiving deferasirox indicated that they would be willing to continue taking it. These results suggest that deferasirox had a positive impact on patients' daily lives.  相似文献   
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73.
The development of new methods to improve skin wound healing may affect the outcomes of a number of medical conditions. Here, we evaluate the molecular and clinical effects of topical 5‐azacytidine on wound healing in rats. 5‐Azacytidine decreases the expression of follistatin‐1, which negatively regulates activins. Activins, in turn, promote cell growth in different tissues, including the skin. Eight‐week‐old male Wistar rats were submitted to 8.0‐mm punch‐wounding in the dorsal region. After 3 days, rats were randomly assigned to receive either a control treatment or the topical application of a solution containing 5‐azacytidine (10 mM) once per day. Photo documentation and sample collection were performed on days 5, 9, and 15. Overall, 5‐azacytidine promoted a significant acceleration of complete wound healing (99.7% ± 0.7.0 vs. 71.2% ± 2.8 on day 15; n = 10; p < 0.01), accompanied by up to threefold reduction in follistatin expression. Histological examination of the skin revealed efficient reepithelization and cell proliferation, as evaluated by the BrdU incorporation method. 5‐Azacytidine treatment also resulted in increased gene expression of transforming growth factor‐beta and the keratinocyte markers involucrin and cytokeratin, as well as decreased expression of cytokines such as tumor necrosis factor‐alpha and interleukin‐10. Lastly, when recombinant follistatin was applied to the skin in parallel with topical 5‐azacytidine, most of the beneficial effects of the drug were lost. Thus, 5‐azacytidine acts, at least in part through the follistatin/activin pathway, to improve skin wound healing in rodents.  相似文献   
74.
Solid lipid nanoparticles (SLN) are a promising drug delivery system for oral administration of poorly-water soluble drugs because of their capacity to increase the solubility of drug molecules when loaded in their lipid matrices, with the resulting improvement of the drug bioavailability. In the present work, we have developed praziquantel (PZQ)-loaded SLN and explored the biological applications of this system for intestinal permeation of PZQ. The effect in vitro on Schistosoma mansoni culture and the cytotoxicity in HepG2 line cell were also evaluated. The results showed a significant decrease in the intestinal absorption of PZQ loaded in SLN compared to free PZQ, suggesting that the SLN matrix could act as reservoir system. In culture of S. mansoni, we observed that PZQ-loaded SLN were more effective than free PZQ, leading the death of the parasites in less time. The result was proportional to doses of PZQ (25 and 50 μg mL−1) and lipid concentration. Regarding cytotoxicity, the encapsulation of PZQ into SLN decreased the toxicity in HepG2 cells in comparison to the free PZQ. From the obtained results, PZQ-loaded SLN could be a new drug delivery system for the schistosomiasis treatment especially in marginalized communities, improving the therapeutic efficacy and reducing the toxic effects of PZQ.  相似文献   
75.
Feline morbillivirus (FeMV) was identified for the first time in stray cats in 2012 in Hong Kong and, since its discovery, it was reported in domestic cats worldwide. Although a potential association between FeMV infection and tubulointerstitial nephritis (TIN) has been suggested, this has not been proven, and the subject remains controversial. TIN is the most frequent histopathological finding in the context of feline chronic kidney disease (CKD), which is one of the major clinical pathologies in feline medicine. FeMV research has mainly focused on defining the epidemiology, the role of FeMV in the development of CKD, and its in vitro tropism, but the pathogenicity of FeMV is still not clear, partly due to its distinctive biological characteristics, as well as to a lack of a cell culture system for its rapid isolation. In this review, we summarize the current knowledge of FeMV infection, including genetic diversity of FeMV strains, epidemiology, pathogenicity, and clinicopathological findings observed in naturally infected cats.  相似文献   
76.

Background  

Human immunodeficiency virus (HIV) infection is very prevalent in Brazil. HIV therapy has been recently associated with coronary heart disease (CHD). Dyslipidemia is a major risk factor for CHD that is frequently described in HIV positive patients, but very few studies have been conducted in Brazilian patients evaluating their lipid profiles.  相似文献   
77.
The feathers of tropical birds were one of the most significant symbols of economic, social, and sacred status in the pre-Columbian Americas. In the Andes, finely produced clothing and textiles containing multicolored feathers of tropical parrots materialized power, prestige, and distinction and were particularly prized by political and religious elites. Here we report 27 complete or partial remains of macaws and amazon parrots from five archaeological sites in the Atacama Desert of northern Chile to improve our understanding of their taxonomic identity, chronology, cultural context, and mechanisms of acquisition. We conducted a multiproxy archaeometric study that included zooarchaeological analysis, isotopic dietary reconstruction, accelerated mass spectrometry radiocarbon dating, and paleogenomic analysis. The results reveal that during the Late Intermediate Period (1100 to 1450 CE), Atacama oasis communities acquired scarlet macaws (Ara macao) and at least five additional translocated parrot species through vast exchange networks that extended more than 500 km toward the eastern Amazonian tropics. Carbon and nitrogen stable isotopes indicate that Atacama aviculturalists sustained these birds on diets rich in marine bird guano-fertilized maize-based foods. The captive rearing of these colorful, exotic, and charismatic birds served to unambiguously signal relational wealth in a context of emergent intercommunity competition.

One of the most pervasive and unambiguous material symbols of prestige, wealth, and spiritual status in the pre-Columbian Americas were long, slender, and brightly colored feathers often worn in elaborated headdresses (14). Feather use and its representation in iconography is recurrently found as a marker of leadership and association with divinity from incipiently stratified communities to consolidated empires (5, 6). In the Andes, the colorful feathers of tropical parrots were often imported from the eastern Amazonian tropical forests by little-understood mechanisms of exchange and trade (79). Although many feathers were transported and maintained in special containers, some tropical birds might have been taken and moved across the Andes alive. The archaeological finding of actual tropical macaws and amazon parrots in specific ritual and funerary contexts provides a unique opportunity to explore the origin of these birds and the management strategies related to their procurement, handling in captivity, and ceremonial interment. Here we reconstructed some of these practices by conducting a multiproxy study involving direct accelerated mass spectrometry (AMS) radiocarbon dating, stable isotope analysis, and paleogenomic sequencing of an assemblage of macaw and amazon parrot remains recovered from archaeological sites located in the Atacama Desert of northern Chile.The Atacama Desert provides remarkable conditions for the preservation of organic materials such as bone, tendons, muscles, skin, and feathers (1012). The evidence associated with the preservation and use of tropical bird feathers in this region has been a topic of recurrent discussion regarding the nature of the social interaction between societies located on both sides of the Andes (8, 13). The Andes were not the only place where these birds and their feathers were widely circulated. Scarlet macaws (Ara macao) were transported and held captive for feathers to mark status and for ceremonial purposes by Ancestral Pueblo, Mimbres, Paquimé, and other pre-Hispanic societies across the arid southwestern US and northwestern Mexico (1416). Moreover, recent technical advances in the study of the pre-Columbian avicultural practices open up a series of possibilities for improving our understanding about ancient social, economic, and religious practices in the Americas, as well as of animal husbandry, procurement strategies, feeding ecology, and biogeography of tropical bird species that are presently threatened (1719).  相似文献   
78.
In plants, endocytosis is essential for many developmental and physiological processes, including regulation of growth and development, hormone perception, nutrient uptake, and defense against pathogens. Our toolbox to modulate this process is, however, rather limited. Here, we report a conditional tool to impair endocytosis. We generated a partially functional TPLATE allele by substituting the most conserved domain of the TPLATE subunit of the endocytic TPLATE complex (TPC). This substitution destabilizes TPC and dampens the efficiency of endocytosis. Short-term heat treatment increases TPC destabilization and reversibly delocalizes TPLATE from the plasma membrane to aggregates in the cytoplasm. This blocks FM uptake and causes accumulation of various known endocytic cargoes at the plasma membrane. Short-term heat treatment therefore transforms the partially functional TPLATE allele into an effective conditional tool to impair endocytosis. Next to their role in endocytosis, several TPC subunits are also implicated in actin-regulated autophagosomal degradation. Inactivating TPC via the WDX mutation, however, does not impair autophagy, thus enabling specific and reversible modulation of endocytosis in planta.

Endocytosis is an evolutionarily conserved eukaryotic pathway by which extracellular material and plasma membrane (PM) components are internalized via vesicles (1, 2). Clathrin-mediated endocytosis (CME), relying on the scaffolding protein clathrin, is the most prominent and the most studied endocytic pathway (35). As clathrin does not interact directly with the PM, nor does it recognize cargoes, adaptor proteins are required to act as essential links between the clathrin coat and the PM (6). In plant cells, material selected for CME is recognized by two adaptor complexes, the adaptor complex 2 (AP-2) and the TPLATE complex (TPC) (79). In contrast to TPC, single subunit mutants of AP-2 are viable (7, 8, 1013) and AP-2 recruitment and dynamics appear to rely on TPC function (8, 14).TPC represents an ancestral adaptor complex, which is however absent in present-day metazoans and yeasts. It was experimentally identified as an octameric complex in Arabidopsis and as a hexametric complex in Dictyostelium (8, 15). Plants, however, are the only eukaryotic supergroup identified so far where TPC is essential for life (8, 15), as knockout or severe knockdown of single subunits of TPC in Arabidopsis leads to pollen or seedling lethality, respectively (8, 13). Two TPC subunits, AtEH1/Pan1 and AtEH2/Pan1, were not associated with the other TPC core components when the complex was forced into the cytoplasm by truncating the TML subunit and did not copurify with the other TSET components in Dictyostelium. This indicates that they may be auxiliary components to the core TPC (8, 15). These AtEH/Pan1 proteins were recently identified as important players in actin-regulated autophagy in plants. AtEH/Pan1 proteins recruit several components of the endocytic machinery to the autophagosomes, and are degraded together with them under stress conditions (16). However, whether this pathway serves to degrade specific cargoes or to regulate the endocytic machinery itself (17), and whether the whole TPC is required for this degradation pathway, remains unclear.Genetic and chemical tools to manipulate endocytosis have been extensively investigated via interfering with the functions of endocytic players, such as clathrin (1822), adaptor proteins (7, 1012, 14, 2325), and dynamin-related proteins (2630). The chemical inhibitors originally used to affect CME in plants have recently been described to possess undesirable side effects (31) or to affect proteins that are not only specific for endocytosis: for example, clathrin itself, as it is also involved in TGN trafficking (19, 22). The same is true for several genetic tools currently available to affect CME in plants (18, 21, 22, 30). Manipulation of TPC, functioning exclusively at the PM, represents a very good candidate to affect CME more specifically. So far however, there are no chemical tools to target TPC functions or dominant-negative mutants available. Inducible silencing works, but causes seedling lethality and takes several days to become effective (8). The only tools to manipulate TPC function in viable plants consist of knock-down mutants with very mild reduction of expression and consequently similar mild effects on CME (8, 14, 16, 32).  相似文献   
79.
Congestion and acute renal dysfunction are at the center of acute heart failure (HF) syndromes. Acute cardiorenal syndrome, which refers to worsening of renal function in a patient with acute HF syndrome, is partly related to venous congestion and high renal afterload. Aggressive decongestion improves renal and myocardial flow and ventricular loading conditions, potentially resulting in reduced HF progression, rehospitalization, and mortality. High‐dose diuretic therapy remains the mainstay therapy. Ultrafiltration and inotropic therapy are useful in the subgroup of patients with a low‐output state and diuretic resistance.  相似文献   
80.
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