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Noorlidah Abdullah Rosnina Abdulghani Siti Marjiana Ismail Mohamad Hamdi Zainal Abidin 《Food and Agricultural Immunology》2017,28(3):374-387
Polysaccharides isolated from mushrooms have recently attracted attention due to its potential immune-stimulatory activity. The aim of this study was to validate the in vitro immune-stimulatory activities of various mushroom extracts. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that Pleurotus eryngii, with the highest β-glucan (18.94%) content, displayed highest viability on macrophage cells of 62.59% at 200?μg/ml concentration. Pleurotus cystidiosus, with 18.16% β-glucan, content showed highest activation of NF-kB (0.7?µg/ml) at a concentration of 100?µg/ml. Termitomyces heimii, with the lowest percentage of β-glucan (0.51%), exhibited highest phagocytosis index of 9.38 at 12.5?µg/ml. The brown strain of Agaricus bisporus with 1.54% of β-glucan stimulates the highest nitric oxide (NO) production of 12.39?µM nitrite oxide at 100?µg/ml. This study revealed that hot water extracts of mushrooms have different β-glucan contents and produced varying immune-stimulatory activities. Among these, Pleurotus spp. demonstrated the highest percentage of β-glucan content and viability of macrophage cells. Pleurotus spp. are deemed immune-stimulatory by increasing phagocytic activity, NO production, and triggered the activation of NF-kB. 相似文献
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Background
Dental caries is still the most prevalent chronic disease worldwide. In the occupied Palestinian territory, data about oral health status and its determinants are scarce. This study aimed to assess the prevalence of dental caries and associated factors among schoolchildren in a random sample of marginalised schools in the West Bank.Methods
Marginalised schools (according to the School Support Program [SPP] criteria) were stratified by district, gender, and grade level to select a random sample of 20 schools. Students in the sixth and ninth grades were interviewed by senior dental students about their oral hygiene and diet habits. Students' weight, height, gingival health, and dental caries experience were assessed. Senior dental students were trained and calibrated to carry out the interviews and the examinations. Parental informed consents were collected by school administrative staff. Ethics approval for the study was obtained from the Al-Quds University Scientific Research Ethics Committee.Findings
In total, 1282 students completed the interviews and the clinical screening. The mean decayed, missing and filled teeth (DMFT) index was 6·4 (SD 4·4). According to the WHO dental caries experience classification, 49% (309 of 623) of the sixth grade students and 74% (484 of 658) of the ninth grade students fell in the high and very high categories. The mother's level of education and recent visit to the dentist correlated negatively with DMFT score (ρ=–0·06, p=0·029; ρ=–0·063, p=0·024). BMI was correlated positively with DMFT (r=0·092, p=0·001). Drinking milk and fresh juices was related to lower DMFT scores (r=–0·077, p=0·006 and r=–0·072, p=0·010). In the final model, grade (β=0·314, p<0·0001), gender (β=0·058, p=0·034), recent visit to the dentist (β=–0·059, p=0·029) and drinking fresh juices (β=–0·054, p=0·047) were significant factors in explaining the high level of dental caries in this sample.Interpretation
Students in the marginalised schools of the West Bank have high DMFT scores that indicate high prevalence of dental caries. Access to dental care and bad oral health habits are associated with high disease prevalence. Interventions to improve access to care and increase awareness about healthy diet and hygiene habits are crucial to alleviate the burden of oral disease in this population.Funding
AMIDEAST School Support Program (SSP). 相似文献97.
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Objective Familial Mediterranean fever (FMF) is an autosomal recessive recurrent polyserositis with a higher prevalence in some ethnic groups, including Turks. Mutations in the FMF gene (MEFV) were found associated with FMF. The aim of this study was to analyze MEFV gene mutations in FMF patients to gain insight into the mutation phenotype correlation.Objectives We analyzed the most frequent mutations (M680I, M694V, V726A, and E148Q) in a group of young male Turkish FMF patients using an amplification refractory mutation system and a commercial kit.Results M694V mutation was detected in 80% of the patients. After making a strict diagnostic discrimination between arthralgia and arthritis, arthritis was present in 71% of homozygous and 29.4% of heterozygous patients for M694V mutation. Other mutations were not found to correlate with specific symptoms or findings.Conclusion The homozygosity of M694V mutation in the MEFV gene is associated with arthritis in FMF patients. 相似文献
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Hereditary vitamin D-resistant rickets (HVDRR) is an autosomal recessive disease caused by mutations in the vitamin D receptor (VDR). We studied a young Saudi Arabian girl who exhibited the typical clinical features of HVDRR, but without alopecia. Analysis of her VDR gene revealed a homozygous T to C mutation in exon 7 that changed isoleucine to threonine at amino acid 268 (I268T). From crystallographic studies of the VDR ligand-binding domain, I268 directly interacts with 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] and is involved in the hydrophobic stabilization of helix H12. We recreated the I268T mutation and analyzed its effects on VDR function. In ligand binding assays, the I268T mutant VDR exhibited an approximately 5- to 10-fold lower affinity for [(3)H]1,25(OH)(2)D(3) compared with the wild-type (WT) VDR. The I268T mutant required approximately a 65-fold higher concentration of 1,25(OH)(2)D(3) to be equipotent in gene transactivation. Both retinoid X receptor heterodimerization and coactivator binding were reduced in the I268T mutant. Analogs of 1,25(OH)(2)D(3) have been proposed as potential therapeutics for patients with HVDRR. Interestingly, in protease sensitivity assays, treatment with the potent vitamin D analog, 20-epi-1,25(OH)(2)D(3), stabilized I268T mutant proteolytic fragments better than 1,25(OH)(2)D(3). Moreover, 20-epi-1,25(OH)(2)D(3) restored transactivation of the I268T mutant to levels exhibited by WT VDR treated with 1,25(OH)(2)D(3). In conclusion, we describe a novel mutation, I268T, in the VDR ligand-binding domain that alters ligand binding, retinoid X receptor heterodimerization, and coactivator binding. These combined defects in VDR function cause resistance to 1,25(OH)(2)D(3) action and result in the syndrome of HVDRR. 相似文献
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Karti SS Ovali E Ozgur O Yilmaz M Sonmez M Ratip S Ozdemir F 《Hepato-gastroenterology》2003,50(54):1864-1866
BACKGROUND/AIMS: Apoptotic and anti-proliferative effects of heparin on a number of cancers have been described. There have been no studies analyzing the effect of heparin on human hepatoma cells. The aim of this study was to investigate the effect of heparin on human hepatoma cell line, HepG2. METHODOLOGY: HepG2 cell line was cultured with different concentrations of heparin. Colony count, viability assay, percentage of the apoptosis and proliferative index were assessed at the end of the 7th day. Trypan blue was used to assess viability. Apoptosis and proliferative indexes were assessed by flow-cytometry. RESULTS: Hepatoma cells were arrested at the G0/G1 phase with heparin incubation and proliferative indexes decreased significantly in 20, 40 and 80 U/mL of heparin concentrations in comparison with the control (36 +/- 1%, 30 +/- 5% and 29 +/- 8% vs. 44 +/- 1%, p < 0.01). Flow cytometry revealed a statistically significant increase in apoptosis in groups incubated with 40 and 80 U/mL of heparin in comparison with the control (39 +/- 26% and 58 +/- 18% vs. 0.83 +/- 1.3%, p < 0.01). Colony counts per well and viable cells per microL decreased significantly in 80 U/mL of heparin. CONCLUSIONS: Heparin leads to a significant anti-proliferative and an apoptotic effect on human hepatoma cells in vitro. 相似文献