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排序方式: 共有587条查询结果,搜索用时 15 毫秒
41.
Liang  Zhuoru  Zhang  Tiantian  Lin  Tengfei  Liu  Lishun  Wang  Binyan  Fu  Alex Z.  Wang  Xiaobin  Xu  Xiping  Luo  Nan  Jiang  Jie 《Quality of life research》2019,28(8):2069-2080
Quality of Life Research - Hypertension is a major global public health problem, including rural China. However, studies examining health-related quality of life (HRQoL) for patients with...  相似文献   
42.
The present study was aimed to evaluate the effect of apigenin 8-C-glucoside (Vitexin) and chlorogenic acid on epileptic mice induced by pilocarpine and explored its possible mechanisms. Intraperitonial administration of pilocarpine (85 mg/kg) induced seizure in mice was assessed by behavior observations, which is significantly (p > 0.05) reduced by apigenin 8-C-glucoside (AP8CG) (10 mg/kg) and chlorogenic acid (CA) (5 mg/kg), similar to diazepam. Seizure was accompanied by an imbalance in the levels of Gamma-aminobutyric acid (GABA) and glutamate in the pilocarpine administered group. Moreover, convulsion along with reduced acetylcholinesterase, increased monoamine oxidase and oxidative stress was observed in epileptic mice brain. AP8CG and CA significantly restored back to normal levels even at lower doses. Further, increased lipid peroxidation and nitrite content was also significantly attenuated by AP8CG and CA. However, CA was found to be more effective when compared to AP8CG. In addition, the mRNA expression of N-methyl-d-aspartate receptor (NMDAR), mGluR1 and mGlu5 was significantly (P  0.05) inhibited by AP8CG and CA in a lower dose. The mRNA expression of GRIK1 did not differ significantly in any of the group and showed a similar pattern of expression. Our result shows that AP8CG and CA selectively inhibit NMDAR, mGluR1 and mGlu5 expression. Modification in the provoked NMDAR calcium response coupled with neuronal death. Hence, these findings underline that the polyphenolics, AP8CG and CA have exerted antiepileptic and neuroprotective activity by suppressing glutamate receptors.  相似文献   
43.
With the development of genetically modified crops, there has been a growing interest in available approaches to assess the potential allergenicity of novel gene products. We were not sure whether Cry1C could induce allergy. We examined the protein with three other proteins to determine the potential allergenicity of Cry1C protein from genetically modified rice. Female Brown Norway (BN) rats received 0.1 mg peanut agglutinin (PNA), 1 mg potato acid phosphatase (PAP), 1 mg ovalbumin (OVA) or 5 mg purified Cry1C protein dissolved in 1 mL water by daily gavage for 42 days to test potential allergenicity. Ten days after the last gavage, rats were orally challenged with antigens, and physiologic and immunologic responses were studied. In contrast to sensitization with PNA, PAP and OVA Cry1C protein did not induce antigen-specific IgG2a in BN rats. Cytokine expression, serum IgE and histamine levels and the number of eosinophils and mast cells in the blood of Cry1C group rats were comparable to the control group rats, which were treated with water alone. As Cry1C did not show any allergenicity, we make the following conclusion that the protein could be safety used in rice or other plants.  相似文献   
44.
The genetically-modified (GM) soybean 3Ø5423 × 40-3-2 expresses siRNA for the fatty acid desaturase-2 enzyme which results in higher concentrations of oleic acid (18:1) relative to linoleic acid (18:2) compared with non-GM soybeans. It also expresses the CP4 EPSPS protein for tolerance to glyphosate. In this study, three different dietary concentrations (7.5%, 15% and 30% wt/wt) of 3Ø5423 × 40-3-2 or non-GM soybeans were fed to Sprague–Dawley rats for 90 days during which in-life nutritional and growth performance variables were evaluated followed by analysis of standard clinical chemistry, hematology and organ variables. Compared with rats fed the non-GM control diet, some statistically significant differences were observed in rats fed the 3Ø5423 × 40-3-2 diet. However the differences were not considered treatment-related and commonly fell within the normal ranges of the control group consuming the commercial diet. These results demonstrated that the GM soybean 3Ø5423 × 40-3-2 is as safe as non-GM soybeans.  相似文献   
45.
Myocarditis is associated with increased number of CD4+ T cells in the myocardium after coxsackievirus B3 (CVB3) infection. Previous studies show that CD11c+ myeloid dendritic cells (mDC) loaded with myosin could induce myocarditis. This study aims to investigate the generation and accumulation of mDC in CVB3-induced myocarditis. The presence of mDC in myocardium was detected by immunohistochemisty. Bone marrow-derived mDC were generated from uninfected and CVB3-infected mice. The percentage of CD11c+ mDC on cultured cells and mean fluorescence index (MFI) of double positive cells (CD11c+CD40+, CD11c+CD80+) were measured by flow cytometry. The expression of chemokine receptors (CCR5, CCR7) on mDC and chemokines (CCL4, CCL19) in the myocardium was detected. The migration of mDC in response to CCL4 or CCL19 was measured by chemotaxis assay. Mature mDC were elevated in the myocardium from CVB3-infected mice. The percentage of mDC generated from CVB3-infected group was increased. The MFI of CD11c+CD40+ and CD11c+CD80+ was increased in CVB3-infected group. The mDC showed a down-regulation of CCR5 and unaffected CCR7 mRAN levels associated with elevated CCL4 and CCL19 in the myocardium in CVB3-infected group. Numbers of migrating bone marrow-derived mDC from CVB3-infected mice were increased in vitro. We conclude that CVB3 infection induced the greater generation of mDC from bone marrow and accumulation of mature mDC in myocardial tissues. This migration was associated with increased levels of both CCL4 and CCL19 in the heart tissue. These suggest that blocking the migration of mDC may provide a novel therapy for myocarditis.  相似文献   
46.
Precise control over the nanoscale presentation of adhesion molecules and other biological factors represents a new frontier for biomaterials science. Recently, the control of integrin spacing and cellular shape has been shown to affect fundamental biological processes, such as differentiation and apoptosis. Here, we present the self-assembly of maleimide functionalised polystyrene-block-poly (ethylene oxide) copolymers as a simple, yet highly precise method for controlling the position of cellular adhesion molecules. By manipulating the phase separation of the functional PS-PEO block copolymer used in this study, via a simple blending technique, we alter the nanoscale (on PEO domains of 8–14 nm in size) presentation of the adhesion peptide, GRGDS, decreasing lateral spacing from 62 nm to 44 nm and increasing the number density from ~450 to ~900 islands per μm2. The results indicate that the spreading of NIH-3T3 fibroblasts increases as the spacing between domains of RGD binding peptides decreases. Further, the same functional PS-PEO surfaces have been utilised to immobilise, via a zinc chelating peptide sequence, poly-histidine tagged proteins and extracellular matrix (ECM) fragments. This method is seen as an ideal platform for investigations into the role of spatial arrangements of cell adhesion molecules and ECM molecules on cell function and, in particular, control of cell phenotype.  相似文献   
47.
Generally, there is an age-related decline in the human gut titer of Bifidobacterium species, but the titer in healthy centenarians was previously reported to be comparable to that found in much younger people. We addressed whether elevated Bifidobacterium titers relate positively to immune function. This study evaluated the immunoactivities of 2 Bifidobacterium strains (B adolescentis BBMN23 and B longum BBMN68) isolated from healthy centenarians in China. Different dosages (2 × 1011, 2 × 109, or 2 × 107 colony-forming units [CFU]/kg body weight) of live bifidobacteria were orally administered once per day to healthy BALB/c mice, and the control group was given sterile skim milk every day. After 4 weeks, the immune parameters including cellular immunity (delayed-type hypersensitivity [DTH], and splenic lymphocyte proliferation), humoral immunity (serum hemolytic activity in immunized animals), and nonspecific immunity (peritoneal macrophages phagocytsis natural killer [NK] cell activity) were measured. We report that both Bifidobacterium strains independently increased the DTH response. Macrophage phagocytosis was also enhanced, while activities of the NK cells and levels of the serum hemolysin also were significantly higher than in the control group. There was a significant increase in splenic lymphocyte proliferation in bifidobacteria treatment animals compared to controls. In conclusion, ingestion of B. adolescentis BBMN23 and B. longum BBMN68 can enhance both innate and acquired immunity in healthy specific pathogen-free (SPF) mice and strains of bifidobacteria from healthy centenarians in Bama longevity villages in China may possess potentially valuable immunomodulatory properties.  相似文献   
48.
Background and aimsEpidemiological evidence of the association between migraines, severe headaches, and hypertension is contradictory. Hypertension is a critical risk factor for cardiovascular diseases. Migraine is a common neurological disease and a major cause of disability worldwide. Therefore, we aimed to investigate the relationship between migraine, severe headaches, and hypertension among US adults.Methods and resultsCross-sectional data from 5716 subjects were obtained from the National Health and Nutrition Examination Survey between 1999 and 2004. Weighted logistic regression models investigated the association between migraines, severe headaches, and hypertension. In total, 5716 subjects were enrolled in the present study, of whom 1134 (19.8%) had migraine or severe headaches. Participants with migraine were predominantly younger females and had a higher body mass index (BMI), lower educational level, lower dietary intake of potassium and calcium, lower serum levels of total cholesterol (TC), creatinine, and hemoglobin, as well as a higher estimated glomerular filtration rate (eGFR) (all P < 0.05). After fully adjusting for potential confounders, migraine or severe headaches were positively associated with hypertension (OR 1.25, 95% CI: 1.03–1.53).ConclusionOur study found a positive association between migraine, severe headaches, and hypertension. Further studies are needed to verify the causality of this association and elucidate the underlying mechanisms.  相似文献   
49.
Background and aimsReducing consumption of sugar-sweetened beverages (SSBs) is a global public health priority because of their limited nutritional value and associations with increased risk of obesity and metabolic diseases. Gut microbiota-related metabolites emerged as quintessential effectors that may mediate impacts of dietary exposures on the modulation of host commensal microbiome and physiological status.Methods and resultsThis study assessed the associations among SSBs, circulating microbial metabolites, and gut microbiota–host co-metabolites, as well as metabolic health outcomes in young Chinese adults (n = 86), from the Carbohydrate Alternatives and Metabolic Phenotypes study in Shaanxi Province. Five principal component analysis-derived beverage drinking patterns were determined on self-reported SSB intakes, which were to a varying degree associated with 143 plasma levels of gut microbiota-related metabolites profiled by untargeted metabolomics. Moreover, carbonated beverages, fruit juice, energy drinks, and bubble tea exhibited positive associations with obesity-related markers and blood lipids, which were further validated in an independent cohort of 16,851 participants from the Regional Ethnic Cohort Study in Northwest China in Shaanxi Province. In contrast, presweetened coffee was negatively associated with the obesity-related traits. A total of 79 metabolites were associated with both SSBs and metabolic markers, particularly obesity markers. Pathway enrichment analysis identified the branched-chain amino acid catabolism and aminoacyl-tRNA biosynthesis as linking SSB intake with metabolic health outcomes.ConclusionOur findings demonstrate the associations between habitual intakes of SSBs and several metabolic markers relevant to noncommunicable diseases, and highlight the critical involvement of gut microbiota-related metabolites in mediating such associations.  相似文献   
50.
Complementary to an efficacy trial carried out under the vitamin A for Africa Partnership, the retention of β-carotene in boiled, mashed orange-fleshed sweet potato (OFSP), variety Resisto, was evaluated. The OFSP contained almost exclusively trans-β-carotene. Studies were done to establish and evaluate the analytical procedure and to assess the natural variability of the β-carotene content of OFSP. Because it was more efficient than other solvents, tetrahydrofuran:methanol (1:1) was chosen for extraction. The high-performance liquid chromatographic method established showed good reproducibility. No loss of β-carotene was observed in chopped/grated raw OFSP allowed to stand for 4 h, indicating that it was not prone to enzymatic oxidation. The β-carotene content of medium-sized OFSP from the same harvest batch ranged from 132 to 194 μg/g. True retention (TR) was assessed using paired samples and a formula that compensated for loss or gain of moisture and soluble solids. TR was 92% when medium-sized OFSP covered with water was boiled for 20 min in a pot with the lid on; without the lid, boiling took 30 min and TR was 88%. When OFSP of different sizes were boiled 30 min, covered with water in a pot with the lid on, TR was 70–80%. Although degradation occurred, the β-carotene content of boiled/mashed OFSP was still substantial.  相似文献   
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