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991.
992.
Although beta‐sitosterol has been well known to have anti‐tumor activity in liver, lung, colon, stomach, breast and prostate cancers via cell cycle arrest and apoptosis induction, the underlying mechanism of anti‐cancer effect of beta‐sitosterol in multiple myeloma cells was never elucidated until now. Thus, in the present study, the role of reactive oxygen species (ROS) in association with AMP‐activated protein kinase (AMPK) and c‐Jun N‐terminal kinase (JNK) pathways was demonstrated in beta‐sitosterol‐treated multiple myeloma U266 cells. Beta‐sitosterol exerted cytotoxicity, increased sub‐G1 apoptotic population and activated caspase‐9 and ‐3, cleaved poly (ADP‐ribose) polymerase (PARP) followed by decrease in mitochondrial potential in U266 cells. Beta‐sitosterol promoted ROS production, activated AMPK, acetyl‐CoA carboxylase (ACC) and JNK in U266 cells. Also, beta‐sitosterol attenuated the phosphorylation of AKT, mammalian target of rapamycin and S6K, and the expression of cyclooxygenase‐2 and VEGF in U266 cells. Conversely, AMPK inhibitor compound C and JNK inhibitor SP600125 suppressed apoptosis induced by beta‐sitosterol in U266 cells. Furthermore, ROS scavenger N‐acetyl L‐cysteine attenuated beta‐sitosterol‐mediated sub‐G1 accumulation, PARP cleavage, JNK and AMPK activation in U266 cells. Overall, these findings for the first time suggest that ROS‐mediated activation of cancer metabolism‐related genes such as AMPK and JNK plays an important role in beta‐sitosterol‐induced apoptosis in U266 multiple myeloma cells. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
993.
BackgroundThe coronavirus disease 2019 (COVID-19) outbreak and subsequent disease-containment measures (such as school closures) significantly affected the lives of adolescents. We evaluated the mental-health status and factors associated with anxiety and depression among South Korean adolescents.MethodsA nationwide online survey was conducted to evaluate the mental-health status of South Korean adolescents during the COVID-19 pandemic. In total, 570 adolescents aged 13–18 years were surveyed between May 27 and June 11, 2021. The participants completed the Generalized Anxiety Disorder Scale (GAD-7) and Patient Health Questionnaire (PHQ-9) to determine anxiety and depression symptoms, respectively. Stepwise logistic regression models were constructed to determine factors related to anxiety and depression.ResultsAmong the study participants, 11.2% and 14.2% had anxiety and depression, respectively. The results suggested that several factors, such as the experience of COVID-19 infection and quarantine of oneself, a family member or an acquaintance, physical and mental health problems, and fear of one’s local community being discriminated against as a COVID-19 area were related to anxiety and depression.ConclusionThe present study identified COVID-19-related factors associated with anxiety and depression among adolescents, and provides insights regarding potential interventions to improve the mental health of adolescents. To promote the mental health of adolescents during the COVID-19 pandemic, special attention should be paid to individuals with physical or mental-health problems, and efforts should be made to reduce the negative social and emotional impacts of infection-control measures.  相似文献   
994.
A phytochemical investigation of the EtOH extract of Hoveniae Lignum yielded four phenolic compounds, phloretin (1), 5-(4'-hydroxyphenyl)-gamma-valerolactone (2), (-)-epiafzelechin (3), and maesopsin (4). Compound 1 was hepatoprotective against tacrine-induced cytotoxicity in human liver-derived Hep G2 cells with an EC50 value of 37.55 +/- 0.42 microM. Compound 1 (0.4-200 microM) also significantly reduced tert-butyl hydroperoxide-induced cytotoxicity in rat primary hepatocytes as measured by the cellular leakage of lactate dehydrogenase and the level of aspartate transaminase.  相似文献   
995.
FGFR4 has been shown to play an important role in the etiology and progression of solid tumors. A single nucleotide polymorphism (SNP) within the FGFR4 gene has previously been linked to prognosis and response to chemotherapy in breast cancer and other malignancies. This study evaluates the relevance of this SNP in advanced ovarian cancer. FGFR4-genotype was analyzed in 236 patients recruited as part of the OVCAD project. Genotyping was performed on germ-line DNA using a TaqMan based genotyping assay. Results were correlated with clinicopathological variables and survival. The FGFR4 388Arg genotype was significantly associated with prolonged progression-free and overall survival (univariate: HR 0.68, p = 0.017; HR 0.49, p = 0.005; multivariate: HR 0.69, p = 0.025; HR 0.49, p = 0.006) though the positive prognostic value was restricted to patients without postoperative residual tumor. Indeed, there was a significant interaction between FGFR4 genotype and residual tumor for overall survival. Furthermore, the FGFR4 388Arg genotype significantly correlated with platinum sensitivity in the same subgroup (multivariate OR 3.81 p = 0.004). FGFR4 Arg388Gly genotype is an independent and strong context specific prognostic factor in patients with advanced ovarian cancer and could be used to predict platinum-sensitivity.  相似文献   
996.
Variants of uncertain clinical significance (VUS) in the high-penetrance breast cancer susceptibility genes BRCA1 and BRCA2 represent a major obstacle in genetic counseling of high-risk breast cancer families. We analyzed a missense VUS located in BRCA2 (p.Asn3124Ile; HGVS: BRCA2 c.9371A > T) present in seven independent high-risk breast cancer families that were counseled and genetically tested in South-West Germany. The VUS was identified by DNA sequencing. We analyzed co-occurrence with deleterious BRCA1/2 mutations, segregation, evolutionary conservation, in silico impact prediction, and prevalence in the general population. All carriers of the VUS suffered from breast or ovarian cancer. In two families, an additional high burden of other cancers such as pancreatic, prostate, and gastric cancers was reported, one further family included two cases of male breast cancer. The VUS did not co-occur with deleterious BRCA1/2 mutations and segregated in two affected individuals of one family. In contrast to the 7/1,347 (0,5 %) tested high-risk BC families without clearly pathogenic mutations in BRCA1/2, none of 3,126 healthy population controls sharing the same ethnic and geographical background were found to carry this VUS (p = 0.0002). In-silico prediction revealed strong evolutionary conservation of the asparagine residue, residing in the C-terminal oligonucleotide-binding-fold-3 region, and a most likely damaging impact of this exchange on the protein structure. The BRCA2 p.Asn3124Ile (BRCA2 c.9371A > T) variant is a rare mutation with a damaging effect on the BRCA2 protein that is strongly associated with familial breast and ovarian cancer risk, indicating its most likely pathogenic nature and clinical relevance.  相似文献   
997.
A study to the fibroblast—populated collagen lattices   总被引:3,自引:0,他引:3  
FDepartmentofOralMaxillofacialSurgery ,2ndClinicalCollegeofChinaMedicalUniversity ,Shenyang 1 1 0 0 0 3,China(WuZQ)DepartmentofOralSurgery ,MedicineandPathology ,DentalSchool,UniversityofWalesCollegeofMedicine ,CardiffCF44XY ,UnitedKingdom (KJDavies ,DWThomas)ibroblas…  相似文献   
998.
复方硫酸氢黄连素灌肠液的抗菌活性研究   总被引:2,自引:0,他引:2  
目的观察复方硫酸氢黄连素灌肠液比单方黄连素制剂抗菌活性是否有所增加.方法采用琼脂平板稀释法和平皿法,并以志贺氏痢疾杆菌感染小鼠为动物模型,测定复方硫酸氢黄连素灌肠液的体内、体外抗菌活性.结果复方制剂比单方制剂的MIC和MBC分别降低1~125倍和1~15倍,抑菌环增大,敏感性增强,体内感染细菌小鼠死亡率降低.结论复方硫酸氢黄连素灌肠液对常见细菌感染比单方黄连素制剂具有较强的抗感染作用.  相似文献   
999.
1000.
BackgroundInflammation is emerging as a potential mechanism of cervical carcinogenesis. However, few studies have investigated the association between host inflammatory status and the natural course of cervical precursor lesion. The aim of this study was to assess the probability of LSIL regression, associated with an inflammatory biomarker, high-sensitivity C-reactive protein (hs-CRP).MethodsIn a longitudinal cohort study, female participants were examined annually or biannually using cervical cytology between 2006 and 2015. Incident LSIL cases were included in the analysis, with regression defined as at least one consecutive normal cytologic result. A total of 520 women aged 22–64 years were followed up for LSIL regression. The multivariable-adjusted hazard ratios (HRs) for LSIL regression were estimated using a parametric proportional hazards model.ResultsDuring 827.5 person-years of follow-up, 486 out of 520 subjects (93.5%) showed LSIL regression. After adjusting several important potential confounders, a higher quartile of hs-CRP levels was significantly associated with a lower rate of regression (for quartile 4 vs quartile 1, inverse HR 1.33; 95% CI, 1.04–1.69; P for trend = 0.028).ConclusionsThe low rate of spontaneous regression recorded in women with higher hs-CRP lends support to the role of the perturbated host inflammatory status in cervical carcinogenesis, and suggests that hs-CRP level could help monitor LSIL.Key words: chronic inflammation, cervix, regression, low-grade squamous intraepithelial lesions, hs-CRP  相似文献   
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