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Perfusion computed tomography (CT) has emerged as a novel functional imaging technique with gradually increasing importance in the management of colorectal cancer (CRC). By providing the functional tumor microvasculature, it also helps the assessment of therapeutic response of anti-angiogenic drugs as it may reflect tumor angiogenesis. Perfusion CT has been applied in clinical practice to delineate inflammatory or neoplastic lymph nodes irrespective of their size, identify micro-metastases and to predict metastases in advance of their development. It is of increasing significance for preoperative adjuvant therapies and avoidance of unnecessary interventions. Despite controversies regarding the techniques employed, its validity and reproducibility, it can be advantageous in the management of CRCs in which the prognosis is dependent on preoperative staging. With recent advances in the perfusion CT techniques, and incorporation to other modalities like positron emission tomography, perfusion CT will be a novel tool in the overall management of CRCs. This article aims at reviewing the existing clinical applications and recent advances of perfusion CT with a reference to future development in the management of CRCs.  相似文献   
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The aim of this study was to generate a reference set of Salmonella enterica genomes isolated from wildlife from the United States and to determine the antimicrobial resistance and virulence gene profile of the isolates from the genome sequence data. We sequenced the whole genomes of 103 Salmonella isolates sampled between 1988 and 2003 from wildlife and exotic pet cases that were submitted to the Oklahoma Animal Disease Diagnostic Laboratory, Stillwater, Oklahoma. Among 103 isolates, 50.48% were from wild birds, 0.9% was from fish, 24.27% each were from reptiles and mammals. 50.48% isolates showed resistance to at least one antibiotic. Resistance against the aminoglycoside streptomycin was most common while 9 isolates were found to be multi-drug resistant having resistance against more than three antibiotics. Determination of virulence gene profile revealed that the genes belonging to csg operons, the fim genes that encode for type 1 fimbriae and the genes belonging to type III secretion system were predominant among the isolates. The universal presence of fimbrial genes and the genes encoded by pathogenicity islands 1–2 among the isolates we report here indicates that these isolates could potentially cause disease in humans. Therefore, the genomes we report here could be a valuable reference point for future traceback investigations when wildlife is considered to be the potential source of human Salmonellosis.  相似文献   
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BACKGROUND: Skin problems are the commonest reason for people accessing healthcare services in Nepal but there is little information about the prevalence of skin disease. OBJECTIVES: To perform a point prevalence study of skin disease in the Terai region of Nepal. METHODS: Five villages were randomly selected in Bara District in the Terai region of Nepal, and 878 people were examined. RESULTS: The number of individuals identified as having a skin disease was 546. The point prevalence of identifiable skin abnormalities was 62.2% (546 of 878) (with 95% exact confidence intervals 58.9-65.4%). A wide range of dermatoses was identified. The six most prevalent were dermatophyte infections (11.4%), followed by pityriasis versicolor (8.9%), acne (7.7%), melasma (6.8%), eczema (5.6%) and pityriasis alba (5.2%). Overall, treatable skin infections and infestations were by far the commonest skin diseases identified. CONCLUSIONS: Our study has demonstrated a very high point prevalence (62.2%) of skin disease in rural Nepal. This study represents the first formal survey of skin disease in Nepal and demonstrates a large burden of disease, in particular treatable infections.  相似文献   
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The methanolic extract of the rhizomes parts of Agelica purpuraefolia was investigated for its activity against chloroquine‐sensitive strains of Plasmodium falciparum using the parasite lactate dehydrogenase assay method. Two natural khellactone, (+)‐4′‐Decanoyl‐cis‐khellactone (1) and (+)‐3′‐Decanoyl‐cis‐khellactone (2) were isolated from the rhizomes parts of A. purpuraefolia. Two compounds were evaluated for in vitro antiplasmodial activities as well as their cytotoxic potential on SK‐OV‐3 cancer cell line cells. Compounds 1, 2 showed notable growth inhibitory activity against chloroquine‐sensitive strains of Plasmodium falciparum with IC50 values from 1.5 and 2.4 μM. This compound showed no significant cytotoxicity (IC50 > 100 μM) evaluated using SK‐OV‐3 cancer cell line cells. This is the first report on the antiplasmodial activity of the compounds from A. purpuraefolia. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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The mechanisms connecting obesity with type 2 diabetes, insulin resistance, nonalcoholic fatty liver disease, and cardiovascular diseases remain incompletely understood. The function of MAPK phosphatase-2 (MKP-2), a type 1 dual-specific phosphatase (DUSP) in whole-body metabolism, and how this contributes to the development of diet-induced obesity, type 2 diabetes (T2D), and insulin resistance is largely unknown. We investigated the physiological contribution of MKP-2 in whole-body metabolism and whether MKP-2 is altered in obesity and human fatty liver disease using MKP-2 knockout mice models and human liver tissue derived from fatty liver disease patients. We demonstrate that, for the first time, MKP-2 expression was upregulated in liver tissue in humans with obesity and fatty liver disease and in insulin-responsive tissues in mice with obesity. MKP-2-deficient mice have enhanced p38 MAPK, JNK, and ERK activities in insulin-responsive tissues compared with wild-type mice. MKP-2 deficiency in mice protects against diet-induced obesity and hepatic steatosis and was accompanied by improved glucose homeostasis and insulin sensitivity. Mkp-2−/− mice are resistant to diet-induced obesity owing to reduced food intake and associated lower respiratory exchange ratio. This was associated with enhanced circulating insulin-like growth factor-1 (IGF-1) and stromal cell-derived factor 1 (SDF-1) levels in Mkp-2−/− mice. PTEN, a negative regulator of Akt, was downregulated in livers of Mkp-2−/− mice, resulting in enhanced Akt activity consistent with increased insulin sensitivity. These studies identify a novel role for MKP-2 in the regulation of systemic metabolism and pathophysiology of obesity-induced insulin resistance and fatty liver disease.  相似文献   
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This study was conducted to explore fungal endophyte communities inhabiting native switchgrass plants from the tallgrass prairie of northern Oklahoma. The primary focus was to isolate these endophytes in pure culture from surface-sterilized plant tissues and provide taxonomic identifications based on comparative analysis of ITS rDNA gene sequences. From these data, we evaluated the biodiversity of these potentially beneficial endosymbionts from this rapidly disappearing habitat of the Great Plains. While important from a strictly conservationist standpoint, this survey further allowed us to identify candidate endophytes for introduction into commercial switchgrass cultivars for biomass enhancement. A total of 210 whole plant samples were collected at early vegetative, full reproductive and senescence stages. Fungal endophytes were isolated, identified to species level when possible, and grouped into communities based on plant part, collection month and part of the prairie from which the plants were collected. Species diversity for each community was estimated by Shannon diversity index, and differences in diversity indices were compared using a t-test. The presence of fungal species representing at least 18 taxonomic orders suggests a high level of diversity in switchgrass endophyte communities. The fungal communities from shoot tissue had significantly higher species diversity than communities from the root tissue. The abundance of taxa assigned to the order Hypocreales (to which mutualistic, clavicipitaceous endophytes of cool-season grasses belong) found in shoot (64%) and root tissues (39%) throughout the growing season suggests great potential for utilizing these endophytes for enhancing biomass production and stress resistance of this important bioenergy crop.  相似文献   
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