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991.
The purpose of this study was to investigate the effects of dietary NiCl2 on antioxidant function, apoptosis, and the protein expression, mRNA expression and contents of the bcl-2, bax and caspase-3 in the cecal tonsil of broilers. 280 one-day-old avian broilers were divided into four groups and fed on a corn–soybean basal diet as control diet or the same basal diet supplemented with 300, 600 and 900 mg/kg of NiCl2 for 42 days. The activities of SOD, CAT and GSH-Px, and the ability to inhibit hydroxy radical, and GSH content were significantly decreased in all experimental groups. MDA content was significantly increased. The protein expression, mRNA expression and contents of bcl-2 were decreased, and bax and caspase-3 were increased in all experimental groups. The percentages of apoptotic lymphocytes were significantly increased. In conclusion, dietary NiCl2 in excess of 300 mg/kg caused oxidative stress, and then induced decreased the protein expression, mRNA expression and the contents of bcl-2, and increased protein expression, mRNA expression and the contents of bax and caspase-3 proteins in the cecal tonsil. The local intestinal mucosal immunity could finally be impaired due to the oxidative stress and apoptosis in the cecal tonsil caused by NiCl2.  相似文献   
992.
In this paper, we report the synthesis, characterization (FT-IR, XRD, BET, HR-TEM) and bioevaluation of a novel γ-aminobutiric acid/silica (noted GABA-SiO2 or γ-SiO2) hybrid nanostructure, for the improved release of topical antibiotics, used in the treatment of Staphylococcus aureus infections. GABA-SiO2 showed IR bands which were assigned to Si–O–Si (stretch mode). The XRD pattern showed a broad peak in the range of 18–30° (2θ), indicating an amorphous structure. Based on the BET analysis, estimations about surface area (438.14 m2/g) and pore diameters (4.76 nm) were done. TEM observation reveals that the prepared structure presented homogeneity and an average size of particles not exceeding 10 nm. The prepared nanostructure has significantly improved the anti-staphylococcal activity of bacitracin and kanamycin sulfate, as demonstrated by the drastic decrease of the minimal inhibitory concentration of the respective antibiotics loaded in the GABA-SiO2 nanostructure. These results, correlated with the high biocompatibility of this porous structure, are highlighting the possibility of using this carrier for the local delivery of the antimicrobial substances in lower active doses, thus reducing their cytotoxicity and side-effects.  相似文献   
993.
目的设计合成头孢美法仑,并对其进行体外抗肿瘤活性研究。方法以二苯甲酮、美法仑和7-苯乙酰胺基-3-氯甲基头孢烷酸对甲氧基苄酯(GCLE)为原料,经酯化、碘代、偶联、氧化、水解等反应得到目标化合物头孢美法仑,并采用MTT法对其进行体外抗肿瘤活性研究。结果设计并合成了目标产物头孢美法仑,利用MS和1H-NMR确证了结构;体外活性实验中,头孢美法仑在体外基本无毒,酶解后IC50为(101.97±1.705)μmol/L。结论头孢美法仑酶解后能够充分发挥细胞毒作用,而酶解前在体外基本无毒性,为颇具前景的前药,值得进一步研究。  相似文献   
994.
Lan  Kaiqi  Xu  Cheng  Liu  Shiliang  Zhu  Jinhan  Yang  Yadi  Zhang  Li  Guo  Suping  Xi  Mian 《Esophagus》2021,18(4):861-871
Esophagus - To develop and validate a nomogram for the prediction of symptomatic radiation pneumonitis (RP) in patients with esophageal squamous cell carcinoma (ESCC) who received definitive...  相似文献   
995.
Abdominal Radiology - To compare tumor detectability and conspicuity of standard b = 1000 s/mm2 (b1000) versus ultrahigh b = 2000 s/mm2 (b2000)...  相似文献   
996.
ObjectivesTo explore the impact of a Mindfulness-Based Stress Reduction (MBSR) intervention for people with metastatic cancer integrated in Early Palliative Care (EPC). Design: Mixed-method study.Settings/LocationEPC Service integrated with Oncology Unit, Carpi General Hospital, Italy from January to October 2017. The MBSR intervention took place inside the hospital.SubjectsStudy participation was offered to 25 consecutive people referred to the EPC service. Inclusion criteria: people with metastatic cancer between 18 and 75 years old; informed consent. Exclusion criteria: Performance Status <60% according to Karnofsky scale; active psychiatric disorder. 20 patients were included in the study.InterventionThe adapted program consists of 8 meetings for 2.5 h once a week, a 4.5 h session between the 6th and 7th weeks and 0.5 h home practice daily. The following mindfulness practices were included during the training: formal sitting meditation, body scan, light yoga, walking meditation, and Aikido exercises. Participants were provided with materials for home practice. A qualified MBSR instructor conducted the program. Sessions were attended by a clinical psychologist and a physician trained in meditation, together with the palliative nurse as facilitators.Outcome MeasuresFeasibility and acceptability were assessed on 16 participants. In addition, pre-post measures of cancer pain and mood state were collected. Semi-structured, in-depth interviews were conducted on a subset of 8 participants at the end of the study and analysed using the Interpretative-Phenomenological approach.ResultsMBSR attendance to meetings and adherence to home practice were 75%. MBSR intervention helped participants to develop an accepting attitude in respect to metastatic cancer disease helping them to face anxiety and cancer pain. MBSR improves self-regulation of mood state engendering feelings of compassion MBSR program supports participants in questioning and reconnecting with their values and spiritual beliefs.ConclusionsA Mindfulness intervention integrated into EPC setting is feasible, well accepted and could help metastatic cancer patients to control cancer pain together with an opportunity of emotional and spiritual relief.  相似文献   
997.
PurposeConducting an overview of systematic reviews (SRs)/Meta analyses (MAs) to assess the effectiveness of cognitive interventions on participants with mild cognitive impairment (MCI) or dementia and evaluate the methodological quality of SRs/MAs.MethodsPubMed, EMBASE, Cochrane library, Web of science, China National Knowledge Infrastructure (CNKI) and Chinese Biomedical Databases (CBM) were systematically searched from inception to January 1, 2019 to identify SRs/MAs. Three reviewers independently screened the articles, extracted data and assessed the quality of the included studies according to the Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR-2), the Grading of Recommendations Assessment Development and Evaluation (GRADE) was used to evaluate the quality of evidence.ResultsA total of 22 reviews were included. New meta-analyses (36 RCTs) showed that cognitive interventions were more effective than routine therapies for the alleviation of MCI and dementia symptoms (SMD: 0.62; 95%CI: 0.47, 0.78; I2 = 53.9%). The results of AMSTAR-2 showed that the methodological quality of most included studies was critically low, and two reviews were low quality. The lowest score was item 10, none of reviews reported on the sources of funding for the included studies. Followed by the “provide a list of excluded studies and justify the exclusions” item with only one (4.5%) reviews conforming to this item. Results of GRADE manifested that moderate quality evidence was provided in 11 reviews (39.3%), 12 (42.9%) were low quality and 5 (17.8%) were very low.ConclusionThe present SRs/MAs indicated that persons with MCI or dementia could benefit from cognitive interventions. Future trial designs should focus on measuring changes in individual specific cognitive functions. More high-quality evidence is needed to further determine the effectiveness of cognitive interventions.  相似文献   
998.
ObjectiveThe present study aimed to evaluate the effectiveness of Nigella sativa L. (N. sativa) extract on preventing the incidence of acute radiation dermatitis (ARD) in breast cancer patients.MethodsSixty-two breast cancer patients undergoing radiotherapy (RT) were randomly assigned to receiveN. sativa 5% gel or placebo. Patients were instructed to apply the medications twice daily during RT period. The severity of ARD, the incidence of moist desquamation, worst experienced pain, and skin-related quality of life (SRQOL) scores were assessed weekly during RT.ResultsPatients who were treated with the N. sativa gel developed ARD significantly less frequently compared to those who used the placebo (p < 0.05 for all weeks except week 2, p = 0.36). The incidence time of grade 2 and 3 of Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer (RTOG/EORTC) toxicity was prolonged significantly with N. sativa gel as compared to placebo (35 vs. 29 days, p = 0.00 and 42 vs. 40 days, p = 0.01, respectively). Furthermore, the occurrence of moist desquamation was delayed in the N. sativa gel group compared with the placebo group (37 vs. 33 days, p = 0.01). The mean score of the worst pain that patients experienced in the placebo group was significantly higher than that of the N. sativa gel group at week 3 (2.5 ± 0.5 vs. 1.2 ± 0.3, p < 0.05). Nonetheless, the application of N. sativa gel had no significant effect on the SRQOL of patients at any week.ConclusionN. sativa extract significantly decreases the severity of ARD and delays the onset of moist desquamation in breast cancer patients.  相似文献   
999.
1000.
The aim of this study was to estimate accuracy, intraobserver variability, and repeatability of thyroid volume measurement by ultrasound using conventional two-dimensional ellipsoid model (2D US) and manual planimetry of three-dimensional images (3D US). The sonographic images of 47 children with thyroid nodular pathology who were referred for thyroid surgery in Belarus were evaluated prospectively. Two-dimensional images were acquired using the ultrasound scanner with 7.5-MHz linear probe. Three-dimensional data sets were created using three-dimensional system, FreeScan. For each patient thyroid volume was measured three times using both two- and three-dimensional methods. Results of volume estimation were then compared to the volume of thyroid gland determined after surgery. Standardized difference between thyroid volume estimated by ultrasound and surgery (mean +/- standard deviation (SD), %) for 3D and 2D US methods was 1.8 +/- 5.2% and 3.2 +/- 15.3%, respectively. The 3D US has lower intraobserver variability (3.4%) and higher repeatability (96.5%) than 2D US with 14.4% variability and 84.8% repeatability (p < 0.001). In conclusion, three-dimensional sonography allows accurate measurement of thyroid volume with low intraobserver variability and high repeatability.  相似文献   
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